Also flagged:testicular cancerPhthalatesphthalategerm cellmono-(2-ethylhexyl)matrix metalloproteinase 2
Journal Article2012-05-31✓ 1 SnippetYao PL, Lin YC, Richburg JH.
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…DCC subclass, member 3…
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Testicular dysgenesis syndrome refers to a collection of diseases in men, including testicular cancer, that arise as a result of abnormal testicular development. Phthalates are a class of chemicals used widely in the production of plastic products and other consumer goods. Unfortunately, phthalate exposure has been linked to reproductive dysfunction and has been shown to adversely affect normal germ cell development. In this study, we show that mono-(2-ethylhexyl) phthalate (MEHP) induces matrix metalloproteinase 2 (MMP2) expression in testicular embryonal carcinoma NT2/D1 cells but has no significant effect on MMP9 expression. NT2/D1 cells also have higher levels of MYC expression following MEHP treatment. It is widely recognized that activation of MMP2 and MYC is tightly associated with tumor metastasis and tumor progression. Gelatin zymographic analysis indicates that MEHP strongly activates MMP2 in NT2/D1 cells. Addition of the MMP2-specific inhibitor SB-3CT inhibited MEHP-enhanced cell invasion and migration, demonstrating that MMP2 plays a functional role in promoting testicular embryonal carcinoma progression in response to MEHP exposure. Furthermore, we investigated genome-wide gene expression profiles of NT2/D1 cells following MEHP exposure at 0, 3, and 24 h. Microarray analysis and semiquantitative RT-PCR revealed that MEHP exposure primarily influenced genes in cell adhesion and transcription in NT2/D1 cells. Gap junction protein-alpha 1, vinculin, and inhibitor of DNA-binding protein-1 were significantly down-regulated by MEHP treatment, while claudin-6 and beta 1-catenin expression levels were up-regulated. This study provides insight into mechanisms that may account for modulating testicular cancer progression following phthalate exposure.
Also flagged:KLEIPcorneal neovascular dystrophyBTB-kelch proteinactin binding proteincell-cell contact
Journal Article2012-05-31✓ 1 SnippetHahn N, Dietz CT, Kühl S, Vossmerbaeumer U, Kroll J.
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Abstract)
…4>The BTB-kelch protein KLEIP/KLHL20is an actin…
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<h4>Purpose</h4>The BTB-kelch protein KLEIP/KLHL20 is an actin binding protein that regulates cell-cell contact formation and cell migration. The aim of our study was to characterize KLEIP's function in ocular health and disease in mice.<h4>Methods</h4>KLEIP(-/-) mice were generated, and corneas were examined histologically and stained for keratin-1, loricrin, keratin-12, keratin-14, CD31, LYVE-1, F4/80, E-cadherin, and Ki67. Corneal abrasions were performed after eyelid opening.<h4>Results</h4>Corneas of KLEIP(+/+) and KLEIP(-/-) mice were indistinguishable at birth. After eyelid opening corneal epithelial hyperplasia started to manifest in KLEIP(-/-) mice, showing a progressive epithelial metaplasia leading to total corneal opacity. In KLEIP(-/-) mice the initial stratified squamous corneal epithelium was altered to an epidermal histo-architecture showing several superficial keratinized cells, cell infiltrations into the stroma, and several apoptotic cells. Skin markers keratin 1 and loricrin were positive, and surface disease was accompanied by deep stromal vascularization. Expression analysis for E-cadherin in KLEIP(-/-) corneas showed acellular areas in the squamous epithelium, indicating a progressive fragile corneal integrity. Removal of the virgin epithelium accelerated strongly development of the epithelial and stromal alterations, identifying mechanical injuries as the major trigger for corneal dystrophy formation and scarification in KLEIP(-/-) mice.<h4>Conclusions</h4>The data identify KLEIP as an important molecule regulating corneal epithelial integrity.
Also flagged:OX40 ligandOX40atopic dermatitisOX40LADpsoriasis vulgaris
Journal Article2012-05-31No SnippetsIlves T, Harvima IT.
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<h4>Background</h4>The interaction between the OX40 ligand (OX40L) and OX40 has been suggested to have pathogenetic significance in atopic dermatitis (AD).<h4>Objective</h4>The purpose of this study was to investigate the expression and relevance of OX40L and OX40 in AD skin.<h4>Methods</h4>OX40L and OX40 were stained immunohistochemically on the cryosections of the lesional and non-lesional skin of 17 subjects with moderate-to-severe AD and of 10 patients with psoriasis vulgaris. Phorbol myristate acetate (PMA) stimulated keratinocytes and cell membrane preparations from PMA-stimulated keratinocytes or LAD-2 mast cells were incubated with peripheral blood mononuclear cells (PBMC) in the presence or absence of blocking monoclonal antibodies to OX40L, CD30L or ICAM-1.<h4>Results</h4>We show for the first time that the staining intensity of OX40L and the number of OX40(+) cells are significantly greater in the lesional dermis than in the healthy-looking dermis in AD (P < 0.001 in both comparisons) and also in psoriasis (P = 0.01 and P < 0.001 respectively), but neither molecule correlate significantly with the clinical severity of AD. Living keratinocytes and cell membranes from LAD-2 mast cells and keratinocytes increased the PBMC proliferation response. Anti-OX40L antibody inhibited, in a similar fashion as anti-ICAM-1 and anti-CD30L, PBMC proliferation induced by LAD-2 membranes, but stimulated that induced by keratinocytes.<h4>Conclusion</h4>Our findings provide evidence for the involvement of OX40 and OX40L in the pathogenesis of AD though they are not specific to AD and in vitro results suggest complex interaction.
Also flagged:LEDGFgene silencingprostate cancerHsp27Lens epithelium-derived growth factorsmall heat-shock protein 27
Journal Article2012-05-31✓ 3 SnippetsBhargavan B, Fatma N, Chhunchha B, Singh V, Kubo E, Singh DP.
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…no. 4051),Prdx6(Santa Cruz Biotechnology;…
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…such as Sp1,Prdx6and β -actin…
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…of Sp1 orPrdx6or β -actin,…
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Lens epithelium-derived growth factor (LEDGF) maintains survival pathways by augmenting the transcription of stress-response genes such as small heat-shock protein 27. Recently, aberrant expression of LEDGF was found in prostate cancer (PC). Herein, we showed that LEDGF overexpression upregulated Hsp27 in PC cells, DU145, PC-3 and LNCaP and promoted antiapoptotic pathways in PCs. We found that these cells had higher abundance of Hsp27, which was correlated with the levels of LEDGF expression. Transactivation assay in DU145 cells revealed that transactivation of Hsp27 was related to the magnitude of LEDGF expression. Silencing of LEDGF in DU145 cells abrogated Hsp27 expression and inhibited stimulated cell proliferation, invasiveness and migration. These cells were arrested in S and G2 phase, and failed to accumulate cyclin B1, and showed increased apoptosis. Furthermore, LEDGF-depleted DU145 cells displayed elevated Bax and cleaved caspase 9 expression and reduced levels of Bcl2, Bcl-(XL). The activated survival pathway(s), ERK1/2 and Akt, were selectively decreased in these cells, which characteristically have lower tumorigenicity. Conversely, the depleted cells, when re-overexpressed with LEDGF or Hsp27, regained tumorigenic properties. Collectively, results reveal the involvement of LEDGF-mediated elevated expression of Hsp27-dependent survival pathway(s) in PC. Our findings suggest new lines of investigation aimed at developing therapies by targeting LEDGF or its aberrant expression-associated stimulated antiapoptotic pathway(s).
This study seeks to test our hypothesis that transgenic induction of miR-210 in mesenchymal stem cells (MSC) simulates the pro-survival effects of ischemic preconditioning (IPC) and that engraftment of (PC)MSC helps in the functional recovery of ischemic heart by miR-210 transfer to host cardiomyocytes through gap junctions. miR-210 expression in MSC was achieved by IPC or nanoparticle-based transfection of miR-210 plasmid ((miR)MSC) and functional recovery of the infarcted heart of rat transplanted with (PC)MSC or (miR)MSC was evaluated. Both (PC)MSC and (miR)MSC showed higher survival under lethal anoxia as compared to (non-PC)MSC and scramble-transfected MSC ((Sc)MSC) controls with concomitantly lower CASP8AP2 expression. Similarly, both (PC)MSC and (miR)MSC survived better and accelerated functional recovery of ischemic heart post-transplantation. To validate our hypothesis that MSC deliver miR-210 to host cardiomyocytes, in vitro co-culture between cardiomyocytes and (PC)MSC or (miR)MSC (using (non-PC)MSC or (Sc)MSC as controls) showed co-localization of miR-210 with gap-junctional connexin-43. miR-210 transfer to cardiomyocytes was blocked by heptanol pretreatment. Moreover, higher survival of cardiomyocytes co-cultured with (PC)MSC was observed with concomitant expression of CASP8AP2 as compared to cardiomyocytes co-cultured with (non-PC)MSC thus suggesting that miR-210 was translocated from MSC to protect host cardiomyocytes. Induction of miR-210 in MSC promoted their survival post-engraftment in the infarcted heart. Moreover, direct transfer of pro-survival miR-210 from (miR)MSC to host cardiomyocytes led to functional recovery of the ischemic heart.
Also flagged:transcription factorslung morphogenesisCebpanaphthaleneC/EBPαantiprotease
Journal Article2012-05-31No SnippetsSato A, Xu Y, Whitsett JA, Ikegami M.
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Many transcription factors that regulate lung morphogenesis during development are reactivated to mediate repairs of the injured adult lung. We hypothesized that CCAAT/enhancer binding protein-α (C/EBPα), a transcription factor critical for perinatal lung maturation, regulates genes required for the normal repair of the bronchiolar epithelium after injury. Transgenic Cebpα(Δ/Δ) mice, in which Cebpa was conditionally deleted from Clara cells and Type II cells after birth, were used in this study. Airway injury was induced in mice by the intraperitoneal administration of naphthalene to ablate bronchiolar epithelial cells. Although the deletion of C/EBPα did not influence lung structure and function under unstressed conditions, C/EBPα was required for the normal repair of terminal bronchiolar epithelium after naphthalene injury. To identify cellular processes that are influenced by C/EBPα during repair, mRNA microarray was performed on terminal bronchiolar epithelial cells isolated by laser-capture microdissection. Normal repair of the terminal bronchiolar epithelium was highly associated with the mRNAs regulating antiprotease activities, and their induction required C/EBPα. The defective deposition of fibronectin in Cebpα(Δ/Δ) mice was associated with increased protease activity and delayed differentiation of FoxJ1-expressing ciliated cells. The fibronectin and ciliated cells were restored by the intratracheal treatment of Cebpα(Δ/Δ) mice with the serine protease inhibitor. In conclusion, C/EBPα regulates the expression of serine protease inhibitors that are required for the normal increase of fibronectin and the restoration of ciliated cells after injury. Treatment with serine protease inhibitor may aid in the recovery of injured bronchiolar epithelial cells, and prevent common chronic lung diseases.
Several lines of evidence have supported a host genetic contribution to vaccine response, but genome-wide assessments for specific determinants have been sparse. Here we describe a genome-wide association study (GWAS) of protective antigen-specific antibody (AbPA) responses among 726 European-Americans who received Anthrax Vaccine Adsorbed (AVA) as part of a clinical trial. After quality control, 736,996 SNPs were tested for association with the AbPA response to 3 or 4 AVA vaccinations given over a 6-month period. No SNP achieved the threshold of genome-wide significance (p=5 × 10(-8)), but suggestive associations (p<1 × 10(-5)) were observed for SNPs in or near the class II region of the major histocompatibility complex (MHC), in the promoter region of SPSB1, and adjacent to MEX3C. Multivariable regression modeling suggested that much of the association signal within the MHC corresponded to previously identified HLA DR-DQ haplotypes involving component HLA-DRB1 alleles of *15:01, *01:01, or *01:02. We estimated the proportion of additive genetic variance explained by common SNP variation for the AbPA response after the 6 month vaccination. This analysis indicated a significant, albeit imprecisely estimated, contribution of variation tagged by common polymorphisms (p=0.032). Future studies will be required to replicate these findings in European Americans and to further elucidate the host genetic factors underlying variable immune response to AVA.
Myo10 is an unconventional myosin that localizes to and induces filopodia, structures that are critical for growing axons. In addition to the ~240-kDa full-length Myo10, brain expresses a ~165 kDa isoform that lacks a functional motor domain and is known as headless Myo10. We and others have hypothesized that headless Myo10 acts as an endogenous dominant negative of full-length Myo10, but this hypothesis has not been tested, and the function of headless Myo10 remains unknown. We find that cortical neurons express both headless and full-length Myo10 and report the first isoform-specific localization of Myo10 in brain, which shows enrichment of headless Myo10 in regions of proliferating and migrating cells, including the embryonic ventricular zone and the postnatal rostral migratory stream. We also find that headless and full-length Myo10 are expressed in embryonic and neuronal stem cells. To directly test the function of headless and full-length Myo10, we used RNAi specific to each isoform in mouse cortical neuron cultures. Knockdown of full-length Myo10 reduces axon outgrowth, whereas knockdown of headless Myo10 increases axon outgrowth. To test whether headless Myo10 antagonizes full-length Myo10, we coexpressed both isoforms in COS-7 cells, which revealed that headless Myo10 suppresses the filopodia-inducing activity of full-length Myo10. Together, these results demonstrate that headless Myo10 can function as a negative regulator of full-length Myo10 and that the two isoforms of Myo10 have opposing roles in axon outgrowth.
<h4>Objective</h4>To determine the effects of age and topographic location on gene expression in human neural retina.<h4>Methods</h4>Macular and peripheral neural retina RNA was isolated from human donor eyes for DNA microarray and quantitative RT-PCR analyses.<h4>Results</h4>Total RNA integrity from human donors was preserved. Hierarchical clustering analysis demonstrates that the gene expression profiles of young, old, macula, and peripheral retina cluster into four distinct groups. Genes which are highly expressed in macular, peripheral, young, or old retina were identified, including inhibitors of Wnt Signaling Pathway (DKK1, FZD10, and SFRP2) which are preferably expressed in the periphery.<h4>Conclusion</h4>The transcriptome of the human retina is affected by age and topographic location. Wnt pathway inhibitors in the periphery may maintain peripheral retinal cells in an undifferentiated state. Understanding the effects of age and topographic location on gene expression may lead to the development of new therapeutic interventions for age-related eye diseases.
Also flagged:peptide hormoneironpathogenesisanemiainflammatory bowel diseasecolitis
Journal Article2012-05-31✓ 1 SnippetShanmugam NK, Ellenbogen S, Trebicka E, Wang L, Mukhopadhyay S, Lacy-Hulbert A, Gallini CA, Garrett WS, Cherayil BJ.
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Introduction)
…ditary hemochromatosis proteinHFEand the type…
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<h4>Background</h4>Abnormal expression of the liver peptide hormone hepcidin, a key regulator of iron homeostasis, contributes to the pathogenesis of anemia in conditions such as inflammatory bowel disease (IBD). Since little is known about the mechanisms that control hepcidin expression during states of intestinal inflammation, we sought to shed light on this issue using mouse models.<h4>Methodology/principal findings</h4>Hepcidin expression was evaluated in two types of intestinal inflammation caused by innate immune activation-dextran sulfate sodium (DSS)-induced colitis in wild-type mice and the spontaneous colitis occurring in T-bet/Rag2-deficient (TRUC) mice. The role of tumor necrosis factor (TNF) α was investigated by in vivo neutralization, and by treatment of a hepatocyte cell line, as well as mice, with the recombinant cytokine. Expression and activation of Smad1, a positive regulator of hepcidin transcription, were assessed during colitis and following administration or neutralization of TNFα. Hepcidin expression progressively decreased with time during DSS colitis, correlating with changes in systemic iron distribution. TNFα inhibited hepcidin expression in cultured hepatocytes and non-colitic mice, while TNFα neutralization during DSS colitis increased it. Similar results were obtained in TRUC mice. These effects involved a TNFα-dependent decrease in Smad1 protein but not mRNA.<h4>Conclusions/significance</h4>TNFα inhibits hepcidin expression in two distinct types of innate colitis, with down-regulation of Smad1 protein playing an important role in this process. This inhibitory effect of TNFα may be superseded by other factors in the context of T cell-mediated colitis given that in the latter form of intestinal inflammation hepcidin is usually up-regulated.
Also flagged:Runx1Down syndromeheart diseaseschromosomeHmgn1Cx40
Journal Article2012-05-31✓ 5 SnippetsRaveau M, Lignon JM, Nalesso V, Duchon A, Groner Y, Sharp AJ, Dembele D, Brault V, Hérault Y.
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Introduction)
…trisomy ranging fromMrpl39to Zfp295 ,…
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…copies of theMrpl39-Sod1 interval.…
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…outside of theMrpl39-Zfp295 interval.…
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…i.e. in theMrpl39-Tiam1 or Kcnj6-Zfp295 interva…
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…outside of theMrpl39-Zfp295 region are contributin…
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Down syndrome (DS) leads to complex phenotypes and is the main genetic cause of birth defects and heart diseases. The Ts65Dn DS mouse model is trisomic for the distal part of mouse chromosome 16 and displays similar features with post-natal lethality and cardiovascular defects. In order to better understand these defects, we defined electrocardiogram (ECG) with a precordial set-up, and we found conduction defects and modifications in wave shape, amplitudes, and durations in Ts65Dn mice. By using a genetic approach consisting of crossing Ts65Dn mice with Ms5Yah mice monosomic for the App-Runx1 genetic interval, we showed that the Ts65Dn viability and ECG were improved by this reduction of gene copy number. Whole-genome expression studies confirmed gene dosage effect in Ts65Dn, Ms5Yah, and Ts65Dn/Ms5Yah hearts and showed an overall perturbation of pathways connected to post-natal lethality (Coq7, Dyrk1a, F5, Gabpa, Hmgn1, Pde10a, Morc3, Slc5a3, and Vwf) and heart function (Tfb1m, Adam19, Slc8a1/Ncx1, and Rcan1). In addition cardiac connexins (Cx40, Cx43) and sodium channel sub-units (Scn5a, Scn1b, Scn10a) were found down-regulated in Ts65Dn atria with additional down-regulation of Cx40 in Ts65Dn ventricles and were likely contributing to conduction defects. All these data pinpoint new cardiac phenotypes in the Ts65Dn, mimicking aspects of human DS features and pathways altered in the mouse model. In addition they highlight the role of the App-Runx1 interval, including Sod1 and Tiam1, in the induction of post-natal lethality and of the cardiac conduction defects in Ts65Dn. These results might lead to new therapeutic strategies to improve the care of DS people.
…structure of thezinc-finger BED domain-containing protein 1BED domain-containing protein…
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Zbed4, a member of the BED subclass of Zinc-finger proteins, is expressed in cone photoreceptors and glial Müller cells of human retina whereas it is only present in Müller cells of mouse retina. To characterize structural and functional properties of Zbed4, enough amounts of purified protein were needed. Thus, recombinant Zbed4 was expressed in E. coli and its refolding conditions optimized for the production of homogenous and functionally active protein. Zbed4's secondary structure, determined by circular dichroism spectroscopy, showed that this protein contains 32% α-helices, 18% β-sheets, 20% turns and 30% unordered structures. CASTing was used to identify the target sites of Zbed4 in DNA. The majority of the DNA fragments obtained contained poly-Gs and some of them had, in addition, the core signature of GC boxes; a few clones had only GC-boxes. With electrophoretic mobility shift assays we demonstrated that Zbed4 binds both not only to DNA and but also to RNA oligonucleotides with very high affinity, interacting with poly-G tracts that have a minimum of 5 Gs; its binding to and GC-box consensus sequences. However, the latter binding depends on the GC-box flanking nucleotides. We also found that Zbed4 interacts in Y79 retinoblastoma cells with nuclear and cytoplasmic proteins Scaffold Attachment Factor B1 (SAFB1), estrogen receptor alpha (ERα), and cellular myosin 9 (MYH9), as shown with immunoprecipitation and mass spectrometry studies as well as gel overlay assays. In addition, immunostaining corroborated the co-localization of Zbed4 with these proteins. Most importantly, in vitro experiments using constructs containing promoters of genes directing expression of the luciferase gene, showed that Zbed4 transactivates the transcription of those promoters with poly-G tracts.
Also flagged:nucleolinCOUP-TFIIbreast cancertamoxifenarginineglycine
Journal Article2012-05-31No SnippetsLitchfield LM, Riggs KA, Hockenberry AM, Oliver LD, Barnhart KG, Cai J, Pierce WM, Ivanova MM, Bates PJ, Appana SN, Datta S, Kulesza P, McBryan J, Young LS, Klinge CM.
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<h4>Introduction</h4>The orphan nuclear receptor COUP-TFII plays an undefined role in breast cancer. Previously we reported lower COUP-TFII expression in tamoxifen/endocrine-resistant versus sensitive breast cancer cell lines. The identification of COUP-TFII-interacting proteins will help to elucidate its mechanism of action as a transcriptional regulator in breast cancer.<h4>Results</h4>FLAG-affinity purification and multidimensional protein identification technology (MudPIT) identified nucleolin among the proteins interacting with COUP-TFII in MCF-7 tamoxifen-sensitive breast cancer cells. Interaction of COUP-TFII and nucleolin was confirmed by coimmunoprecipitation of endogenous proteins in MCF-7 and T47D breast cancer cells. In vitro studies revealed that COUP-TFII interacts with the C-terminal arginine-glycine repeat (RGG) domain of nucleolin. Functional interaction between COUP-TFII and nucleolin was indicated by studies showing that siRNA knockdown of nucleolin and an oligonucleotide aptamer that targets nucleolin, AS1411, inhibited endogenous COUP-TFII-stimulated RARB2 expression in MCF-7 and T47D cells. Chromatin immunoprecipitation revealed COUP-TFII occupancy of the RARB2 promoter was increased by all-trans retinoic acid (atRA). RARβ2 regulated gene RRIG1 was increased by atRA and COUP-TFII transfection and inhibited by siCOUP-TFII. Immunohistochemical staining of breast tumor microarrays showed nuclear COUP-TFII and nucleolin staining was correlated in invasive ductal carcinomas. COUP-TFII staining correlated with ERα, SRC-1, AIB1, Pea3, MMP2, and phospho-Src and was reduced with increased tumor grade.<h4>Conclusions</h4>Our data indicate that nucleolin plays a coregulatory role in transcriptional regulation of the tumor suppressor RARB2 by COUP-TFII.
Journal Article2012-05-31✓ 5 SnippetsDulger AC, Esen R, Mete R, Begenik H, Aytemiz E, Tasdemir M, Ebinc S, Aslan M.
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Abstract)
…The C282Y and H63D mutations of the HFE gene are principally responsible for HFE-related hemochromatosis.…
Abstract)
…Methods: Using the reverse hybridization Hemochromatosis Strip Assay A (ViennaLab, Profiblot T-48, Tecan), DNA extracted from the blood samples of 159 healthy men was analyzed for different mutations in the HFE gene.…
Abstract Background: Hereditary hemochromatosis (HH) is characterized by an increased intestinal absorption of iron due to mutations in iron-related genes. The C282Y and H63D mutations of the HFE gene are principally responsible for HFE-related hemochromatosis. The majority of HH cases are reported in Western countries where HFE-related mutations are common. The prevalence of HFE-related mutations is not yet clear in eastern Turkey. We aim to clarify the frequency of HFE gene mutations in men who live in eastern Turkey and also assess the biochemical effects of the H63D mutation. Methods: Using the reverse hybridization Hemochromatosis Strip Assay A (ViennaLab, Profiblot T-48, Tecan), DNA extracted from the blood samples of 159 healthy men was analyzed for different mutations in the HFE gene. Results: The H63D mutation was found with an overall carrier frequency of 5.6% (7% heterozygous and 2% homozygous). We also noted that the C282Y gene mutation was not detected in the study. In subjects with the H63D mutation, there were significantly elevated levels both of serum iron and transferrin saturation (p<0.05). Other hematologic and biochemical tests were in the normal ranges in H63D-positive subjects. Conclusions: A lack of C282Y mutations has been reported as a basic finding for non-Western countries and Turkey. H63D mutations in the HFE gene may cause higher levels of serum iron and transferrin saturation. Both may be useful as simple screening tools for HH.
Also flagged:esophageal carcinomaesophageal carcinomastumorPOLImethylationtumors
Journal Article2012-05-30✓ 1 SnippetZhou J, Zhang S, Xie L, Liu P, Xie F, Wu J, Cao J, Ding WQ.
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The present study investigated the transcriptional regulation of low-fidelity translesion DNA synthesis (TLS) polymerases in human esophageal carcinoma. Significantly higher mRNA expression of polymerase zeta (Polξ), RAD18, polymerase iota (Polι), and polymerase kappa (Polκ) was found in esophageal carcinomas. The increased expression of Polι in tumor samples was further confirmed by immunohistochemistry. The promoter of POLI that encodes Polι was found to be hypomethylated, although the overexpression of this gene was unlikely to be associated with methylation in tumors. We further identified Sp1 and Oct-1 binding sites present in the POLI promoter. We observed that the binding affinity of Sp1 to the POLI promoter was significantly increased in cancerous tissues and that Sp1 activated POLI gene transcription in cultured cell lines. The present study demonstrates overexpression of the TLS genes in esophageal carcinoma and identifies a key role for Sp1 in upregulating POLI gene expression.
<h4>Background</h4>Cases with subcutaneous metastasis of differentiated hepatocellular carcinoma to the abdominal wall without prior seeding as a consequence of local interventions with a negative or normal alpha-fetoprotein level in the serum are extremely rare.<h4>Case report</h4>This is the first report of a case with AFP-negative, differentiated hepatocellular carcinoma metastasis to the abdominal wall within a pre-existing subcutaneous lipoma since childhood after antiandrogen therapy with leuprorelin and buserelin acetate for prostate cancer without seeding.<h4>Methods</h4>Clinical features including histology, immunohistochemistry, clinical course and surgical approach are presented.<h4>Results</h4>Histological examination revealed a hepatocellular carcinoma with a trabecular and pseudoglandular growth pattern with moderately atypical hepatocytes with multifocal bile formation within a lipoma. The postoperative course of abdominal wall reconstruction with a monocryl-prolene mesh and a local flap after potentially curative resection was uncomplicated.<h4>Discussion and conclusion</h4>It may be that previous antiandrogen treatment for prostate carcinoma contributed to the fact that our patient developed alpha-fetoprotein-negative and androgen receptor-negative subcutaneous abdominal wall metastasis within a pre-existing lipoma since childhood.
Also flagged:ironmetabolic syndromeinsulin resistanceglucose intolerancedyslipidemiahypertension
Journal Article2012-05-30✓ 3 SnippetsHouschyar KS, Lüdtke R, Dobos GJ, Kalus U, Broecker-Preuss M, Rampp T, Brinkhaus B, Michalsen A.
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Introduction)
…population studies, thehemochromatosisgenotype and increased…
Methods)
…2) history ofhemochromatosisor presence of…
Discussion)
…carriers of thehemochromatosisgene [ 20…
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<h4>Background</h4>Metabolic syndrome (METS) is an increasingly prevalent but poorly understood clinical condition characterized by insulin resistance, glucose intolerance, dyslipidemia, hypertension, and obesity. Increased oxidative stress catalyzed by accumulation of iron in excess of physiologic requirements has been implicated in the pathogenesis of METS, but the relationships between cause and effect remain uncertain. We tested the hypothesis that phlebotomy-induced reduction of body iron stores would alter the clinical presentation of METS, using a randomized trial.<h4>Methods</h4>In a randomized, controlled, single-blind clinical trial, 64 patients with METS were randomly assigned to iron reduction by phlebotomy (n = 33) or to a control group (n = 31), which was offered phlebotomy at the end of the study (waiting-list design). The iron-reduction patients had 300 ml of blood removed at entry and between 250 and 500 ml removed after 4 weeks, depending on ferritin levels at study entry. Primary outcomes were change in systolic blood pressure (SBP) and insulin sensitivity as measured by Homeostatic Model Assessment (HOMA) index after 6 weeks. Secondary outcomes included HbA1c, plasma glucose, blood lipids, and heart rate (HR).<h4>Results</h4>SBP decreased from 148.5 ± 12.3 mmHg to 130.5 ± 11.8 mmHg in the phlebotomy group, and from 144.7 ± 14.4 mmHg to 143.8 ± 11.9 mmHg in the control group (difference -16.6 mmHg; 95% CI -20.7 to -12.5; P < 0.001). No significant effect on HOMA index was seen. With regard to secondary outcomes, blood glucose, HbA1c, low-density lipoprotein/high-density lipoprotein ratio, and HR were significantly decreased by phlebotomy. Changes in BP and HOMA index correlated with ferritin reduction.<h4>Conclusions</h4>In patients with METS, phlebotomy, with consecutive reduction of body iron stores, lowered BP and resulted in improvements in markers of cardiovascular risk and glycemic control. Blood donation may have beneficial effects for blood donors with METS.<h4>Trial registration</h4>ClinicalTrials.gov: NCT01328210 Please see related article: http://www.biomedcentral.com/1741-7015/10/53.
Also flagged:virus infectionimmune responsedegradationinterferon regulatory factor 3IRF3transcription factor
Journal Article2012-05-30No SnippetsDoehle BP, Chang K, Fleming L, McNevin J, Hladik F, McElrath MJ, Gale M.
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Acute virus infection induces a cell-intrinsic innate immune response comprising our first line of immunity to limit virus replication and spread, but viruses have developed strategies to overcome these defenses. HIV-1 is a major public health problem; however, the virus-host interactions that regulate innate immune defenses against HIV-1 are not fully defined. We have recently identified the viral protein Vpu to be a key determinant responsible for HIV-1 targeting and degradation of interferon regulatory factor 3 (IRF3), a central transcription factor driving host cell innate immunity. IRF3 plays a major role in pathogen recognition receptor (PRR) signaling of innate immunity to drive the expression of type I interferon (IFN) and interferon-stimulated genes (ISGs), including a variety of HIV restriction factors, that serve to limit viral replication directly and/or program adaptive immunity. Here we interrogate the cellular responses to target cell infection with Vpu-deficient HIV-1 strains. Remarkably, in the absence of Vpu, HIV-1 triggers a potent intracellular innate immune response that suppresses infection. Thus, HIV-1 can be recognized by PRRs within the host cell to trigger an innate immune response, and this response is unmasked only in the absence of Vpu. Vpu modulation of IRF3 therefore prevents virus induction of specific innate defense programs that could otherwise limit infection. These observations show that HIV-1 can indeed be recognized as a pathogen in infected cells and provide a novel and effective platform for defining the native innate immune programs of target cells of HIV-1 infection.
Huntington disease (HD) is an inherited neurodegenerative disorder caused by an abnormal polyglutamine expansion in the protein Huntingtin (Htt). Currently, no cure is available for HD. The mechanisms by which mutant Htt causes neuronal dysfunction and degeneration remain to be fully elucidated. Nevertheless, mitochondrial dysfunction has been suggested as a key event mediating mutant Htt-induced neurotoxicity because neurons are energy-demanding and particularly susceptible to energy deficits and oxidative stress. SIRT3, a member of sirtuin family, is localized to mitochondria and has been implicated in energy metabolism. Notably, we found that cells expressing mutant Htt displayed reduced SIRT3 levels. trans-(-)-ε-Viniferin (viniferin), a natural product among our 22 collected naturally occurring and semisynthetic stilbenic compounds, significantly attenuated mutant Htt-induced depletion of SIRT3 and protected cells from mutant Htt. We demonstrate that viniferin decreases levels of reactive oxygen species and prevents loss of mitochondrial membrane potential in cells expressing mutant Htt. Expression of mutant Htt results in decreased deacetylase activity of SIRT3 and further leads to reduction in cellular NAD(+) levels and mitochondrial biogenesis in cells. Viniferin activates AMP-activated kinase and enhances mitochondrial biogenesis. Knockdown of SIRT3 significantly inhibited viniferin-mediated AMP-activated kinase activation and diminished the neuroprotective effects of viniferin, suggesting that SIRT3 mediates the neuroprotection of viniferin. In conclusion, we establish a novel role for mitochondrial SIRT3 in HD pathogenesis and discovered a natural product that has potent neuroprotection in HD models. Our results suggest that increasing mitochondrial SIRT3 might be considered as a new therapeutic approach to counteract HD, as well as other neurodegenerative diseases with similar mechanisms.
In comparison with other primate species, humans have an extended juvenile period during which the brain is more plastic. In the current study we sought to examine gene expression in the cerebral cortex during development in the context of this adaptive plasticity. We introduce an approach designed to discriminate genes with variable as opposed to uniform patterns of gene expression and found that greater inter-individual variance is observed among children than among adults. For the 337 transcripts that show this pattern, we found a significant overrepresentation of genes annotated to the immune system process (pFDR ~/= 0). Moreover, genes known to be important in neuronal function, such as brain-derived neurotrophic factor (BDNF), are included among the genes more variably expressed in childhood. We propose that the developmental period of heightened childhood neuronal plasticity is characterized by more dynamic patterns of gene expression in the cerebral cortex compared to adulthood when the brain is less plastic. That an overabundance of these genes are annotated to the immune system suggests that the functions of these genes can be thought of not only in the context of antigen processing and presentation, but also in the context of nervous system development.
Also flagged:Aldosteronecardiac hypertrophyalpha-Myosin Heavy Chainbeta-MyHCarterial hypertensioncardiac hyperaldosteronism
Journal Article2012-05-30✓ 5 SnippetsAzibani F, Devaux Y, Coutance G, Schlossarek S, Polidano E, Fazal L, Merval R, Carrier L, Solal AC, Chatziantoniou C, Launay JM, Samuel JL, Delcayre C.
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Results)
…In addition, aldosterone increased Sox6 expression in NMCM with or without AngII (Figure 5E).…
Results)
…Furthermore, in AS-Ren mice the expression profiles of miR-208a, Sox6, miR-208b (Figure 5 A, C and B) and of β-MyHC (Figure 2D) were reversed by eplerenone (+250%, −50%, +221%, +242%, respectively, vs. untreated AS-Ren) indicating involvement of the MR pathway.…
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…(E): quantitative RT-PCR analysis of Sox6 expression in NMCM stimulated by 10−5 M AngII in the presence or absence of aldosterone (10−9 M or 10−7 M).…
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…(B-D): quantitative RT-PCR analysis of miR-208a, Sox6 and miR-208b expression in 9 month-old WT, AS, R and AS-R mice and in AS-R eplerenone treated mice (100 mg/Kg/day) for one month.…
Abstract)
…its transcriptional repressorSox6.…
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<h4>Background</h4>Arterial hypertension (AH) induces cardiac hypertrophy and reactivation of "fetal" gene expression. In rodent heart, alpha-Myosin Heavy Chain (MyHC) and its micro-RNA miR-208a regulate the expression of beta-MyHC and of its intronic miR-208b. However, the role of aldosterone in these processes remains unclear.<h4>Methodology/principal findings</h4>RT-PCR and western-blot were used to investigate the genes modulated by arterial hypertension and cardiac hyperaldosteronism. We developed a model of double-transgenic mice (AS-Ren) with cardiac hyperaldosteronism (AS mice) and systemic hypertension (Ren). AS-Ren mice had increased (x2) angiotensin II in plasma and increased (x2) aldosterone in heart. Ren and AS-Ren mice had a robust and similar hypertension (+70%) versus their controls. Anatomical data and echocardiography showed a worsening of cardiac hypertrophy (+41%) in AS-Ren mice (P<0.05 vs Ren). The increase of ANP (x 2.5; P<0.01) mRNA observed in Ren mice was blunted in AS-Ren mice. This non-induction of antitrophic natriuretic peptides may be involved in the higher trophic cardiac response in AS-Ren mice, as indicated by the markedly reduced cardiac hypertrophy in ANP-infused AS-Ren mice for one month. Besides, the AH-induced increase of ßMyHC and its intronic miRNA-208b was prevented in AS-Ren. The inhibition of miR 208a (-75%, p<0.001) in AS-Ren mice compared to AS was associated with increased Sox 6 mRNA (x 1.34; p<0.05), an inhibitor of ßMyHC transcription. Eplerenone prevented all aldosterone-dependent effects.<h4>Conclusions/significance</h4>Our results indicate that increased aldosterone in heart inhibits the induction of atrial natriuretic peptide expression, via the mineralocorticoid receptor. This worsens cardiac hypertrophy without changing blood pressure. Moreover, this work reveals an original aldosterone-dependent inhibition of miR-208a in hypertension, resulting in the inhibition of β-myosin heavy chain expression through the induction of its transcriptional repressor Sox6. Thus, aldosterone inhibits the fetal program and increases cardiac hypertrophy in hypertensive mice.
Also flagged:Systemic lupus erythematosusSLEautoimmune diseaseantibodieslupuspathogenesis
Journal Article2012-05-29No SnippetsGuerra SG, Vyse TJ, Cunninghame Graham DS.
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Systemic lupus erythematosus (SLE) is an autoimmune disease with a strong genetic component and is characterized by chronic inflammation and the production of anti-nuclear auto-antibodies. In the era of genome-wide association studies (GWASs), elucidating the genetic factors present in SLE has been a very successful endeavor; 28 confirmed disease susceptibility loci have been mapped. In this review, we summarize the current understanding of the genetics of lupus and focus on the strongest associated risk loci found to date (P <1.0 × 10-8). Although these loci account for less than 10% of the genetic heritability and therefore do not account for the bulk of the disease heritability, they do implicate important pathways, which contribute to SLE pathogenesis. Consequently, the main focus of the review is to outline the genetic variants in the known associated loci and then to explore the potential functional consequences of the associated variants. We also highlight the genetic overlap of these loci with other autoimmune diseases, which indicates common pathogenic mechanisms. The importance of developing functional assays will be discussed and each of them will be instrumental in furthering our understanding of these associated variants and loci. Finally, we indicate that performing a larger SLE GWAS and applying a more targeted set of methods, such as the ImmunoChip and next generation sequencing methodology, are important for identifying additional loci and enhancing our understanding of the pathogenesis of SLE.
Also flagged:asthmaGLCCI1corticosteroidsteroidcorticosteroidsCRHR1
Journal Article2012-05-29No SnippetsMcGeachie MJ, Wu AC, Chang HH, Lima JJ, Peters SP, Tantisira KG.
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Inhaled corticosteroids (ICS) are the most commonly used controller medications prescribed for asthma. Two single-nucleotide polymorphisms (SNPs), rs1876828 in corticotrophin releasing hormone receptor 1 and rs37973 in GLCCI1, have previously been associated with corticosteroid efficacy. We studied data from four existing clinical trials of asthmatics, who received ICS and had lung function measured by forced expiratory volume in 1 s (FEV1) before and after the period of such treatment. We combined the two SNPs rs37973 and rs1876828 into a predictive test of FEV1 change using a Bayesian model, which identified patients with good or poor steroid response (highest or lowest quartile, respectively) with predictive performance of 65.7% (P=0.039 vs random) area under the receiver-operator characteristic curve in the training population and 65.9% (P=0.025 vs random) in the test population. These findings show that two genetic variants can be combined into a predictive test that achieves similar accuracy and superior replicability compared with single SNP predictors.
Also flagged:tumorscardiovascular diseasediabetesneurological disorderscancercolon tumors
Journal Article2012-05-29No SnippetsParasramka MA, Dashwood WM, Wang R, Abdelli A, Bailey GS, Williams DE, Ho E, Dashwood RH.
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<h4>Scope</h4>MicroRNA (miRNA) profiles are altered in chronic conditions such as cardiovascular disease, diabetes, neurological disorders, and cancer. A systems biology approach was used to examine, for the first time, miRNAs altered in rat colon tumors induced by 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), a heterocyclic amine carcinogen from cooked meat.<h4>Methods and results</h4>Among the most highly dysregulated miRNAs were those belonging to the let-7 family. Subsequent computational modeling and target validation identified c-Myc and miRNA-binding proteins Lin28A/Lin28B (Lin28) as key players, along with Sox2, Nanog, and Oct-3/4. These targets of altered miRNAs in colon cancers have been implicated in tumor recurrence and reduced patient survival, in addition to their role as pluripotency factors. In parallel with these findings, the tumor-suppressive effects of dietary spinach given postinitiation correlated with elevated levels of let-7 family members and partial normalization of c-myc, Sox2, Nanog, Oct-3/4, HmgA2, Dnmt3b, and P53 expression.<h4>Conclusion</h4>We conclude that the let-7/c-Myc/Lin28 axis is dysregulated in heterocyclic amine-induced colon carcinogenesis, and that the tumor suppressive effects of dietary spinach are associated with partial normalization of this pathway.
Also flagged:methanolglutathionepolyacrylamidehydroxyapatitewaterGS
Journal Article2012-05-29No SnippetsHan Y, He DS, Liu Y, Xie S, Tsukuda T, Li ZY.
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A method of single-shot imaging via aberration-corrected scanning transmission electron microscopy equipped with high angle annular dark-field detector (STEM-HAADF) has been applied to size-selected gold model catalysts (Au(25) and Au(39) ) on hydroxyapatite. Through quantitative intensity analysis, the size, in terms of number of atoms as well as 3D shape of the clusters are obtained.
…r = -.15) and a weakly significant negative correlation between tumor grade and ER (ICC, r = -.17) as well as PR (ICC, r = -.24; DCC, r = -.14).…
Results)
…r = .46;DCC[dextran-coated charcoal], r…
Results)
…(ICC) and 67% (DCC) of cases, patients…
Results)
…(ICC) and 81% (DCC) of cases.…
Results)
…r = -18;DCC.…
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<h4>Background</h4>The Reporting Recommendations for Tumor Marker Prognostic Studies (REMARK) checklist consists of 20 items to report for published tumor marker prognostic studies. It was developed to address widespread deficiencies in the reporting of such studies. In this paper we expand on the REMARK checklist to enhance its use and effectiveness through better understanding of the intent of each item and why the information is important to report.<h4>Methods</h4>REMARK recommends including a transparent and full description of research goals and hypotheses, subject selection, specimen and assay considerations, marker measurement methods, statistical design and analysis, and study results. Each checklist item is explained and accompanied by published examples of good reporting, and relevant empirical evidence of the quality of reporting. We give prominence to discussion of the 'REMARK profile', a suggested tabular format for summarizing key study details.<h4>Summary</h4>The paper provides a comprehensive overview to educate on good reporting and provide a valuable reference for the many issues to consider when designing, conducting, and analyzing tumor marker studies and prognostic studies in medicine in general. To encourage dissemination of the Reporting Recommendations for Tumor Marker Prognostic Studies (REMARK): Explanation and Elaboration, this article has also been published in PLoS Medicine.
Also flagged:Dok2membrane glycoproteinCD200CD200 receptorCD200Rmultiple sclerosis
Journal Article2012-05-29✓ 1 SnippetLyons A, Downer EJ, Costello DA, Murphy N, Lynch MA.
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Methods)
…prepared from maleC57BL/six micemice (five to…
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<h4>Background</h4>The interaction between the membrane glycoprotein, CD200 and its cognate receptor CD200 receptor (CD200R), has been shown to play a role in maintaining microglia in a quiescent state. There is evidence of increased activation under resting and stimulated conditions in microglia prepared from CD200-deficient mice compared with wild-type mice, whereas activation of the receptor by CD200 fusion protein (CD200Fc) ameliorates inflammatory changes which are evident in the central nervous system (CNS) of the mouse model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis (EAE) and also in the hippocampus of aged rats. Additionally, an inverse relationship between microglial activation and expression of CD200 has been observed in animals treated with lipopolysaccharide (LPS) or amyloid-β (Aβ).<h4>Methods</h4>We assessed the effect of CD200R activation by CD200Fc on Aβ-induced production of the pro-inflammatory cytokines, interleukin-1β (IL-1β) and tumor necrosis factor-α (TNFα) and the expression of microglial activation markers, CD68 and CD40 in cultured glia. The role played by downstream of tyrosine kinase 2 (Dok2) phosphorylation in mediating the effects of CD200R activation was evaluated by siRNA knockdown of Dok2. To further examine the impact of inflammatory changes on synaptic plasticity, the effect of CD200Fc on Aβ-induced impairment of long-term potentiation (LTP) in the CA1 region of hippocampal slices was also investigated.<h4>Results</h4>We demonstrate that Aβ-induced increases in IL-1β, TNFα, CD68 and CD40 were inhibited by CD200Fc. The evidence suggests that Dok2 phosphorylation is a key factor in mediating the effect of CD200Fc, since Dok2 knockdown by siRNA abrogated its effects on microglial activation and inflammatory cytokine production. Consistent with evidence that inflammatory changes negatively impact on LTP, we show that the Aβ-induced impairment of LTP was attenuated by CD200Fc.<h4>Conclusions</h4>The findings suggest that activation of CD200R and Dok2 is a valuable strategy for modulating microglial activation and may have therapeutic potential in neurodegenerative conditions.
Journal Article2012-05-29No SnippetsWerneburg NW, Bronk SF, Guicciardi ME, Thomas L, Dikeakos JD, Thomas G, Gores GJ.
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Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis of liver cancer cell lines requires death receptor-5 (DR5)-dependent permeabilization of lysosomal membranes. Ligated DR5 triggers recruitment of the proapoptotic proteins Bim and Bax to lysosomes, releasing cathepsin B into the cytosol where it mediates mitochondria membrane permeabilization and activation of executioner caspases. Despite the requirement for lysosome membrane permeabilization during TRAIL-induced apoptosis, little is known about the mechanism that controls recruitment of Bim and Bax to lysosomal membranes. Here we report that TRAIL induces recruitment of the multifunctional sorting protein phosphofurin acidic cluster sorting protein-2 (PACS-2) to DR5-positive endosomes in Huh-7 cells where it forms an immunoprecipitatable complex with Bim and Bax on lysosomal membranes. shRNA-targeted knockdown of PACS-2 prevents recruitment of Bim or Bax to lysosomes, blunting the TRAIL-induced lysosome membrane permeabilization. Consistent with the reduced lysosome membrane permeabilization, shRNA knockdown of PACS-2 in Huh-7 cells reduced TRAIL-induced apoptosis and increased clonogenic cell survival. The determination that recombinant PACS-2 bound Bim but not Bax in vitro and that shRNA knockdown of Bim blocked Bax recruitment to lysosomes suggests that TRAIL/DR5 triggers endosomal PACS-2 to recruit Bim and Bax to lysosomes to release cathepsin B and induce apoptosis. Together, these findings provide insight into the lysosomal pathway of apoptosis.
Also flagged:chromatinresponse to hypoxiaGLUT3SLC2A3hypoxia-inducible factor 1HIF1
Journal Article2012-05-29✓ 1 SnippetMimura I, Nangaku M, Kanki Y, Tsutsumi S, Inoue T, Kohro T, Yamamoto S, Fujita T, Shimamura T, Suehiro J, Taguchi A, Kobayashi M, Tanimura K, Inagaki T, Tanaka T, Hamakubo T, Sakai J, Aburatani H, Kodama T, Wada Y.
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…PTGIS…
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Hypoxia-inducible factor 1 (HIF1) is a master regulator of adaptive gene expression under hypoxia. However, a role for HIF1 in the epigenetic regulation remains unknown. Genome-wide analysis of HIF1 binding sites (chromatin immunoprecipitation [ChIP] with deep sequencing) of endothelial cells clarified that HIF1 mainly binds to the intergenic regions distal from transcriptional starting sites under both normoxia and hypoxia. Next, we examined the temporal profile of gene expression under hypoxic conditions by using DNA microarrays. We clarified that early hypoxia-responsive genes are functionally associated with glycolysis, including GLUT3 (SLC2A3). Acetylated lysine 27 of histone 3 covered the HIF1 binding sites, and HIF1 functioned as an enhancer of SLC2A3 by interaction with lysine (K)-specific demethylase 3A (KDM3A). Knockdown of HIF1α and KDM3A showed that glycolytic genes are regulated by both HIF1 and KDM3A and respond to hypoxia in a manner independent of cell type specificity. We elucidated that both the chromatin conformational structure and histone modification change under hypoxic conditions and enhance the expression of SLC2A3 based on the combined results of chromatin conformation capture (3C) and ChIP assays. KDM3A is recruited to the SLC2A3 locus in an HIF1-dependent manner and demethylates H3K9me2 so as to upregulate its expression. These findings provide novel insights into the interaction between HIF1 and KDM3A and also the epigenetic regulation of HIF1.
Constitutive NF-κB activation by proinflammatory cytokines plays a major role in cancer progression. However, the underlying mechanism is still unclear. We report here that histone methyltransferase NSD2 (also known as MMSET or WHSC1), a target of bromodomain protein ANCCA/ATAD2, acts as a strong coactivator of NF-κB by directly interacting with NF-κB for activation of target genes, including those for interleukin-6 (IL-6), IL-8, vascular endothelial growth factor A (VEGFA), cyclin D, Bcl-2, and survivin, in castration-resistant prostate cancer (CRPC) cells. NSD2 is recruited to the target gene promoters upon induction and mediates NF-κB activation-associated elevation of histone H3K36me2 and H3K36me3 marks at the promoter, which involves its methylase activity. Interestingly, we found that NSD2 is also critical for cytokine-induced recruitment of NF-κB and acetyltransferase p300 and histone hyperacetylation. Importantly, NSD2 is overexpressed in prostate cancer tumors, and its overexpression correlates with NF-κB activation. Furthermore, NSD2 expression is strongly induced by tumor necrosis factor alpha (TNF-α) and IL-6 via NF-κB and plays a crucial role in tumor growth. These results identify NSD2 to be a key chromatin regulator of NF-κB and mediator of the cytokine autocrine loop for constitutive NF-κB activation and emphasize the important roles played by NSD2 in cancer cell proliferation and survival and tumor growth.
Also flagged:agingage-related diseasescytoplasmicinsulin-like growth factordaf-2juglone
Journal Article2012-05-29✓ 1 SnippetMoronetti Mazzeo LE, Dersh D, Boccitto M, Kalb RG, Lamitina T.
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…HTT…
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Many age-related diseases are known to elicit protein misfolding and aggregation. Whereas environmental stressors, such as temperature, oxidative stress, and osmotic stress, can also damage proteins, it is not known whether aging and the environment impact protein folding in the same or different ways. Using polyQ reporters of protein folding in both Caenorhabditis elegans and mammalian cell culture, we show that osmotic stress, but not other proteotoxic stressors, induces rapid (minutes) cytoplasmic polyQ aggregation. Osmotic stress-induced polyQ aggregates could be distinguished from aging-induced polyQ aggregates based on morphological, biophysical, cell biological, and biochemical criteria, suggesting that they are a unique misfolded-protein species. The insulin-like growth factor signaling mutant daf-2, which inhibits age-induced polyQ aggregation and protects C. elegans from stress, did not prevent the formation of stress-induced polyQ aggregates. However, osmotic stress resistance mutants, which genetically activate the osmotic stress response, strongly inhibited the formation of osmotic polyQ aggregates. Our findings show that in vivo, the same protein can adopt distinct aggregation states depending on the initiating stressor and that stress and aging impact the proteome in related but distinct ways.
Also flagged:cDNAEgr1Ptgs2adenocarcinomagene expressioncyclin L1
Journal Article2012-05-29No SnippetsKoltsova SV, Trushina Y, Haloui M, Akimova OA, Tremblay J, Hamet P, Orlov SN.
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Stimulus-dependent elevation of intracellular Ca(2+) ([Ca(2+)](i)) affects the expression of numerous genes--a phenomenon known as excitation-transcription coupling. Recently, we found that increases in [Na(+)](i) trigger c-Fos expression via a novel Ca(2+) (i)-independent pathway. In the present study, we identified ubiquitous and tissue-specific [Na(+)](i)/[K(+)](i)-sensitive transcriptomes by comparative analysis of differentially expressed genes in vascular smooth muscle cells from rat aorta (RVSMC), the human adenocarcinoma cell line HeLa, and human umbilical vein endothelial cells (HUVEC). To augment [Na(+)](i) and reduce [K(+)](i), cells were treated for 3 hrs with the Na(+),K(+)-ATPase inhibitor ouabain or placed for the same time in the K(+)-free medium. Employing Affymetrix-based technology, we detected changes in expression levels of 684, 737 and 1839 transcripts in HeLa, HUVEC and RVSMC, respectively, that were highly correlated between two treatments (p<0.0001; R(2)>0.62). Among these Na(+) (i)/K(+) (i)-sensitive genes, 80 transcripts were common for all three types of cells. To establish if changes in gene expression are dependent on increases in [Ca(2+)](i), we performed identical experiments in Ca(2+)-free media supplemented with extracellular and intracellular Ca(2+) chelators. Surprisingly, this procedure elevated rather than decreased the number of ubiquitous and cell-type specific Na(+) (i)/K(+) (i)-sensitive genes. Among the ubiquitous Na(+) (i)/K(+) (i)-sensitive genes whose expression was regulated independently of the presence of Ca(2+) chelators by more than 3-fold, we discovered several transcription factors (Fos, Jun, Hes1, Nfkbia), interleukin-6, protein phosphatase 1 regulatory subunit, dual specificity phosphatase (Dusp8), prostaglandin-endoperoxide synthase 2, cyclin L1, whereas expression of metallopeptidase Adamts1, adrenomedulin, Dups1, Dusp10 and Dusp16 was detected exclusively in Ca(2+)-depleted cells. Overall, our findings indicate that Ca(2+) (i)-independent mechanisms of excitation-transcription coupling are involved in transcriptomic alterations triggered by elevation of the [Na(+)](i)/[K(+)](i) ratio. There results likely have profound implications for normal and pathological regulation of mammalian cells, including sustained excitation of neuronal cells, intensive exercise and ischemia-triggered disorders.
Also flagged:pilocytic astrocytomaArnold-Chiari malformationanaplastic oligodendrogliomaoligodendrogliomaastrocytomamixed oligoastrocytoma
Journal Article2012-05-29✓ 5 SnippetsWu X, Li Y, Wan X, Kayira TM, Cao R, Ju X, Zhu X, Zhao G.
In-Text Gene Mentions
Discussion)
…In agreement with expression of other dependent receptors like DCC and UNC5H which have been regarded as tumor suppressors because of their reported loss of function in variety of cancers and pro-apoptotic ability [41], [42].…
Discussion)
…Our findings on neogenin methylation were in harmony with other dependent receptors such as DCC and UNC5H, where their loss of expression in several cancers was due to promoter methylation [44], [45].…
Discussion)
…As expected, the phenotype for loss of neogenin expression could be similar to DCC, inactivation of which helped to further glioma progression and glioblastoma regeneration [27], [43].…
Abstract)
…Neogenin, aDCChomologue, well known…
Introduction)
…in Colorectal Cancer (DCC), is widely distributed…
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<h4>Background</h4>Dependence receptors have been proved to act as tumor suppressors in tumorigenesis. Neogenin, a DCC homologue, well known for its fundamental role in axon guidance and cellular differentiation, is also a dependence receptor functioning to control apoptosis. However, loss of neogenin has been reported in several kinds of cancers, but its role in glioma remains to be further investigated.<h4>Methodology/principal findings</h4>Western blot analysis showed that neogenin level was lower in glioma tissues than in their matching surrounding non-neoplastic tissues (n = 13, p<0.01). By immunohistochemical analysis of 69 primary and 16 paired initial and recurrent glioma sections, we found that the loss of neogenin did not only correlate negatively with glioma malignancy (n = 69, p<0.01), but also glioma recurrence (n = 16, p<0.05). Kaplan-Meier plot and Cox proportional hazards modelling showed that over-expressive neogenin could prolong the tumor latency (n = 69, p<0.001, 1187.6 ± 162.6 days versus 687.4 ± 254.2 days) and restrain high-grade glioma development (n = 69, p<0.01, HR: 0.264, 95% CI: 0.102 to 0.687). By Methylation specific polymerase chain reaction (MSP), we reported that neogenin promoter was methylated in 31.0% (9/29) gliomas, but absent in 3 kinds of glioma cell lines. Interestingly, the prevalence of methylation in high-grade gliomas was higher than low-grade gliomas and non-neoplastic brain tissues (n = 33, p<0.05) and overall methylation rate increased as glioma malignancy advanced. Furthermore, when cells were over-expressed by neogenin, the apoptotic rate in SHG-44 was increased to 39.7% compared with 8.1% in the blank control (p<0.01) and 9.3% in the negative control (p<0.01).<h4>Conclusions/significance</h4>These observations recapitulated the proposed role of neogenin as a tumor suppressor in gliomas and we suggest its down-regulation owing to promoter methylation is a selective advantage for glioma genesis, progression and recurrence. Furthermore, the induction of apoptosis in SHG-44 cells after overexpression of neogenin, indicated that neogenin could be a novel target for glioma therapy.
…r = −.15) and a weakly significant negative correlation between tumor grade and ER (ICC, r = −.17) as well as PR (ICC, r = −.24; DCC, r = −.14).…
Results)
…(ICC) and 67% (DCC) of cases, patients…
Results)
…(ICC) and 81% (DCC) of cases.…
Results)
…r = −18;DCC.…
Results)
…r = −.24;DCC, r = −.14).…
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The REMARK (Reporting Recommendations for Tumor Marker Prognostic Studies) guideline includes a checklist which aims to improve the reporting of these types of studies. Here, we expand on the REMARK checklist to enhance its use and effectiveness through better understanding of the intent of each item and why the information is important to report. Each checklist item of the REMARK guideline is explained in detail and accompanied by published examples of good reporting. The paper provides a comprehensive overview to educate on good reporting and provide a valuable reference of issues to consider when designing, conducting, and analyzing tumor marker studies and prognostic studies in medicine in general.
Also flagged:hydroxyapatitewaternitrogenammoniumpolyacrylic acidtetramethylammonium
Journal Article2012-05-29No SnippetsSun L, Parker ST, Syoji D, Wang X, Lewis JA, Kaplan DL.
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3D silk/HA microperiodic scaffolds for bone tissue engineering and angiogenesis are fabricated by direct-write assembly. This approach can be used to control filament and spacing size in the scaffold to allow investigation of the effect of scaffold architecture on osteogenesis and vessel-like structure formation from stem cells and endothelial cells.
Research suggests that a polymorphism in the promoter region of the serotonin transporter promoter (5-HTTLPR) interacts with stressful life events to predict depressive onset, with short (s) allele presence associated with greater susceptibility to stressors. However, this research has not considered that depressed individuals often actively generate stressful contexts. Furthermore, little is known about the genetic basis of stress generation. The current study explored the role of 5-HTTLPR genotype in stress generation in a longitudinal sample of 381 adolescents, oversampled for maternal depression, assessed at ages 15 and 20. Genotype did not correlate directly with number or ratings of stressful life events. However, 5-HTTLPR genotype interacted with depression at age 15 to predict dependent stressful events at age 20. Specifically, participants with one or more s alleles showed a stronger association between age 15 depression and age 20 dependent and interpersonal events than long allele homozygotes. Results imply that the 5-HTTLPR genotype predicts reciprocal associations between stress and depression, indicating a more complex relationship between stress, depression, and their genetic underpinnings than previously suggested.
Genome cyclization through conserved RNA sequences located in the 5' and 3' terminal regions of flavivirus genomic RNA is essential for virus replication. Although the role of various cis-acting RNA elements in panhandle formation is well characterized, almost nothing is known about the potential contribution of protein cofactors to viral RNA cyclization. Proteins with nucleic acid chaperone activities are encoded by many viruses (e.g., retroviruses, coronaviruses) to facilitate RNA structural rearrangements and RNA-RNA interactions during the viral replicative cycle. Since the core protein of flaviviruses is also endowed with potent RNA chaperone activities, we decided to examine the effect of West Nile virus (WNV) core on 5'-3' genomic RNA annealing in vitro. Core protein binding resulted in a dramatic, dose-dependent increase in 5'-3' complex formation. Mutations introduced in either the UAR (upstream AUG region) or CS (conserved sequence) elements of the viral RNA diminished core protein-dependent annealing, while compensatory mutations restored the 5'-3' RNA interaction. The activity responsible for stimulating RNA annealing was mapped to the C-terminal RNA-binding region of WNV core protein. These results indicate that core protein - besides its function in viral particle formation - might be involved in the regulation of flavivirus genomic RNA cyclization, and thus virus replication.
Also flagged:NF-κBTumor Necrosis Factor Receptormembrane receptorsOX40CD134TNFRSF4
Journal Article2012-05-28✓ 2 SnippetsSo T, Croft M.
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Abstract)
…by OX40L (CD252,TNFSF4) expressed on antigen-present…
Introduction)
…Upon OX40L (TNFSF4) stimulation, this signaling…
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Antigen primed T lymphocytes need to expand and persist to promote adaptive immunity. The growth and survival signals that control this are in large part provided by the NF-κB pathway in activated or effector/memory T cells. Although several membrane receptors impact NF-κB activation, signaling from OX40 (CD134, TNFRSF4), a member of the tumor necrosis factor receptor (TNFR) superfamily, has proven to be important for T cell immunity and a strong contributor to NF-κB activity. PKCθ directs the T cell receptor (TCR) and CD28-dependent assembly of a CBM complex (CARMA1, BCL10, and MALT1) for efficient activation of NF-κB, raising the question of whether other membrane bound receptors that activate NF-κB also require this PKCθ-CBM axis to control TCR-independent T cell activity. We discuss here our recent data demonstrating that after ligation by OX40L (CD252, TNFSF4) expressed on antigen-presenting cells, OX40 translocates into detergent-insoluble membrane lipid microdomains (DIM or lipid rafts) in T cells irrespective of TCR signals, and assembles into a signaling complex containing PKCθ, together with TRAF2, RIP1, the CBM complex, and the IKKα/β/Γ complex. PKCθ is required for optimal NF-κB activation mediated by OX40 and thus works as an essential component of this OX40 signalosome. We also discuss the likelihood that other TNFR superfamily molecules might complex with PKCθ in T cells, and whether PKC isoforms may be critical to the function of TNFR molecules in general.
Also flagged:cardiovascular diseasegene expressionTHBS1glycoproteinLeft ventricular hypertrophyHLA-B
Journal Article2012-05-28✓ 2 SnippetsZhi D, Irvin MR, Gu CC, Stoddard AJ, Lorier R, Matter A, Rao DC, Srinivasasainagendra V, Tiwari HK, Turner A, Broeckel U, Arnett DK.
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Abstract)
…including HLA-B ,HTT, MTSS1 ,…
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…), huntingtin (HTT), metastasis suppressor…
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<h4>Rationale</h4>Left ventricular hypertrophy (LVH) is a heritable predictor of cardiovascular disease, particularly in blacks.<h4>Objective</h4>Determine the feasibility of combining evidence from two distinct but complementary experimental approaches to identify novel genetic predictors of increased LV mass.<h4>Methods</h4>Whole-exome sequencing (WES) was conducted in seven African-American sibling trios ascertained on high average familial LV mass indexed to height (LVMHT) using Illumina HiSeq technology. Identified missense or nonsense (MS/NS) mutations were examined for association with LVMHT using linear mixed models adjusted for age, sex, body weight, and familial relationship. To functionally assess WES findings, human induced pluripotent stem cell-derived cardiomyocytes (induced pluripotent stem cell-CM) were stimulated to induce hypertrophy; mRNA sequencing (RNA-seq) was used to determine gene expression differences associated with hypertrophy onset. Statistically significant findings under both experimental approaches identified LVH candidate genes. Candidate genes were further prioritized by seven supportive criteria that included additional association tests (two criteria), regional linkage evidence in the larger HyperGEN cohort (one criterion), and publically available gene and variant based annotations (four criteria).<h4>Results</h4>WES reads covered 91% of the target capture region (of size 37.2 MB) with an average coverage of 65×. WES identified 31,426 MS/NS mutations among the 21 individuals. A total of 295 MS/NS variants in 265 genes were associated with LVMHT with q-value <0.25. Of the 265 WES genes, 44 were differentially expressed (P < 0.05) in hypertrophied cells. Among the 44 candidate genes identified, 5, including HLA-B, HTT, MTSS1, SLC5A12, and THBS1, met 3 of 7 supporting criteria. THBS1 encodes an adhesive glycoprotein that promotes matrix preservation in pressure-overload LVH. THBS1 gene expression was 34% higher in hypertrophied cells (P = 0.0003) and a predicted conserved and damaging NS variant in exon 13 (A2099G) was significantly associated with LVHMT (P = 4 × 10(-6)).<h4>Conclusion</h4>Combining evidence from cutting-edge genetic and cellular experiments can enable identification of novel LVH risk loci.
Perinatal hemochromatosis (PH) includes neonatal acute liver failure (ALF) with cirrhosis and extrahepatic iron overload sparing the reticuloendothelial system. This is the main cause of neonatal ALF. Prognosis is very poor, usually with neonatal death or neonatal orthotopic liver transplantation occurring in more than 70%. The recurrence rate is more than 90%. Diagnosis is hard to make and is proved after exclusion of other neonatal ALF causes. A recent physiopathological hypothesis proposed HP as a maternofetal alloimmune disease against the fetal liver. A maternal antibody may activate the terminal complement cascade, responsible for the membrane attack complex directed against fetal hepatocytes. Maternal prenatal treatment after a pregnancy complicated by PH modifies the course and the prognosis of this disease. In France, approval of prenatal IVIG treatment is required after analysis of clinical and pathological data by a national multidisciplinary committee.
Also flagged:irinotecanfolatetumorcamptothecinliposomeammonium
Journal Article2012-05-26No SnippetsZhang Z, Yao J.
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The purpose of this study was to investigate the in vivo distribution and antitumor activity of irinotecan (camptothecin (CPT)-11)-loaded folate-targeted liposome (F-Lip) in tumor-bearing mice following i.v. administration. Folate-poly(ethylene glycol)-distearoylphosphatidylcholine (FA-PEG-DSPE) was synthesized by amide reaction of DSPE-PEG-NH(2) and FA. F-Lip modified by FA-PEG-DSPE was prepared by an ammonium sulfate gradient. The mean particle size and entrapment efficiency of F-Lip with negative charge were 197.8 ± 4.58 nm and 91.39 ± 2.34 %, respectively. The distributions of CPT-11 and SN-38 in the tumor after i.v. administration of F-Lip, CPT-11-loaded liposomes (C-Lip), and CPT-11 injection (C-Inj) were far greater with the F-Lip group in comparison to the C-Inj and C-Lip, which might contribute to folate-meditated targeting uptake by the folate receptor on the surface of the tumor cells. The uptake of CPT-11 in the liver and rectum for two liposome groups were all markedly increased as compared to the C-Inj. Moreover, F-Lip exhibited a dose-dependent tumor growth inhibition and superior anticancer activity to C-Lip and C-Inj after i.v. administration. It also showed no significant body weight loss and much lower toxicity on the center immune organs. Therefore, F-Lip may be presented as potential candidates for tumor targeting drug delivery.
Also flagged:synthesiscinnamic acidssecretionHBeAgInucleoside
Journal Article2012-05-26No SnippetsWang LJ, Geng CA, Ma YB, Luo J, Huang XY, Chen H, Zhou NJ, Zhang XM, Chen JJ.
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Forty-six conjugated derivatives of caudatin with substituted cinnamic acids were synthesized, and their anti-hepatitis B virus (HBV) activity was evaluated in HepG 2.2.15 cells. Most of the derivatives exhibited potent anti-HBV activity, especially inhibiting the HBV DNA replication with the IC(50) values from 2.44 to 22.89 μΜ. Compound 18 showed significant activity against the secretion of HBsAg, HBeAg, and HBV DNA replication with IC(50) values of 5.52, 5.52, 2.44 μΜ, respectively, and had good safety (LD(50) > 1250 mg/kg) according to the acute toxicity study. Preliminary mechanism investigation suggested that compound 18 exerted antivirus effects via interfering HBV X promoter and enhancer I to influence HBV transcriptions.
…functional significance of E277K and V295A HFE mutations . …
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…mutation in theHFEgene.…
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…However, otherHFEalterations have been…
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…consequences of twoHFEmutations, c.829G>A (p.E277K)…
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…mutations partially abrogateHFEassociation with B2M…
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Hereditary haemochromatosis (HH) is an autosomal recessive disorder characterized by excessive intestinal iron absorption resulting in increased pathological body iron stores. It is typically associated with homozygosity for the c.845G>A (p.C282Y) mutation in the HFE gene. However, other HFE alterations have been reported in affected individuals but their association with the disease is unclear. This study analysed the functional consequences of two HFE mutations, c.829G>A (p.E277K) and c.884T>C (p.V295A). Firstly, it was shown that c.829G>A affects the HFE splicing by diminishing the full length HFE and ivs4_66bp inclusion transcript levels, while increasing the amount of exon 4 skipping transcript. Immunofluorescent techniques showed that the HFE_E277K protein had a diffuse distribution (similar to HFE_C282Y) while HFE_V295A presented at the cell surface and perinuclear compartments (resembling HFE_wt). Immunoprecipitation assays revealed a decreased association of HFE_E277K and HFE_V295A with both β2-microglobulin (B2M; 38 ± 7% and 66 ± 8%, respectively) and transferrin receptor (TFRC, also termed TFR1) (58 ± 2% and 49 ± 16%, respectively). Herein, we prove that both mutations partially abrogate HFE association with B2M and TFRC, crucial for its correct processing and cell surface presentation. Although E277K has a more deleterious effect than V295A, we propose that both mutations may play a role in the development of hereditary haemochromatosis.
Huntington's disease (HD) is an autosomal dominant neurodegenerative disease caused by a CAG trinucleotide expansion in the Huntingtin (Htt) gene. When the number of CAG repeats exceeds 36, the translated polyglutamine-expanded Htt protein interferes with the normal functions of many types of cellular machinery and causes cytotoxicity. Clinical symptoms include progressive involuntary movement disorders, psychiatric signs, cognitive decline, dementia, and a shortened lifespan. The most severe brain atrophy is observed in the striatum and cortex. Besides the well-characterized neuronal defects, recent studies showed that the functions of mitochondria and several key players in energy homeostasis are abnormally regulated during HD progression. Energy dysregulation thus is now recognized as an important pathogenic pathway of HD. This review focuses on the importance of three key molecular determinants (peroxisome proliferator-activated receptor-γ coactivator-1α, AMP-activated protein kinase, and creatine kinase B) of cellular energy homeostasis and their possible involvement in HD pathogenesis.
Also flagged:protein Cprotein SATPCPSthrombophilia
Journal Article2012-05-25✓ 1 SnippetCaspers M, Pavlova A, Driesen J, Harbrecht U, Klamroth R, Kadar J, Fischer R, Kemkes-Matthes B, Oldenburg J.
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Abstract)
…found for theSERPINC1gene (83.5%), followed…
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Deficiencies of natural anticoagulant proteins including antithrombin (AT), protein C (PC) and protein S (PS) are important causes of inherited thrombophilia. This study aimed to report on the practical experience gained in performing genetic analyses of a large cohort of patients with AT, PC and PS deficiencies and to relate this knowledge to clinical application. We genotyped a large cohort of 709 unrelated patients with AT (231), PC (234) and PS (244) deficiencies referred to us by physicians throughout Germany. Mutations were detected by direct sequencing and multiplex ligation-dependent probe amplification (MLPA). The highest mutation detection rate (MDR) was found for the SERPINC1 gene (83.5%), followed by the PROC (69%) and PROS1 (43%) genes. Even at AT activities close to the normal range (75%), the MDR was 70%. Contrastingly, for PC and PS deficiencies, the MDR dropped significantly and mildly lowered to subnormal values. At PS activities >55% for PS no mutations were detected. Mutation profiles of all three genes were similar with the highest prevalence for missense mutations (63-78%), followed by nonsense (7-11%), splice-site mutations (7-13%), small deletions (1-8%), small insertions/duplications (1-4%) and large deletions (3-6%). In conclusion, genetic testing is a useful diagnostic tool for diagnosing thrombophilia. Based on our data, genetic analysis for patients with AT deficiency is indicated for all subnormal activities. In contrast, genotyping is not advisable for PC activities >70% and for PS activities >55%.
Also flagged:depressionbehavioralserotonin5-hydroxyindole-3-acetic acidserotonin transporterbrain-derived neurotrophic factor
Journal Article2012-05-25✓ 3 SnippetsPark H, Yoo D, Kwon S, Yoo TW, Park HJ, Hahm DH, Lee H, Kim ST.
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Abstract)
…of serotonin transporter (5-HTT) and brain-derived neurotroph…
Abstract)
…ratio and of5-HTTexpression by acupuncture…
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…5-HTT…
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A possible application of acupuncture in alleviating depression-like behavioral changes and regulating serotonin signaling in the prefrontal cortex (PFC) of maternally-separated rat pups was investigated in this study. On postnatal day 15, rat pups were maternally-separated and received acupuncture stimulation at acupoint HT7 or ST36 once a day for 7 days. On postnatal day 21, the tail suspension test was performed and the PFC was harvested. Tissue levels of serotonin (5-HT) and 5-hydroxyindole-3-acetic acid (5-HIAA) were then measured by high-performance liquid chromatography and expression of serotonin transporter (5-HTT) and brain-derived neurotrophic factor (BDNF) were assessed by western blotting. Levels of 5-HT and 5-HIAA were not significantly changed, but the 5-HIAA/5-HT ratio was significantly increased by maternal separation. The immobility time of maternally-separated rat pups was increased, and increased 5-HTT expression and reduced BDNF level were observed in the PFC. But acupuncture stimulation at HT7 alleviated the behavioral change and regulated the changes of 5-HIAA/5-HT ratio, 5-HTT, and BDNF. In conclusion, acupuncture stimulation at HT7 can relieve maternal separation-induced changes, and we propose that regulation of the 5-HIAA/5-HT ratio and of 5-HTT expression by acupuncture stimulation are important acupuncture-induced benefits in this animal model of depression.
Also flagged:colorectal cancerWntLgr5Ascl2Bmi1adenomas
Journal Article2012-05-25✓ 3 SnippetsZiskin JL, Dunlap D, Yaylaoglu M, Fodor IK, Forrest WF, Patel R, Ge N, Hutchins GG, Pine JK, Quirke P, Koeppen H, Jubb AM.
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Abstract)
…However, Olfm4 was not found to be a useful marker of Lgr5(+) cells in normal colon or tumours.…
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…with Cdk6, Gpx2,Olfm4or Tnfrsf19.…
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…However,Olfm4was not found…
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<h4>Objective</h4>Wnt/Tcf, Lgr5, Ascl2 and/or Bmi1 signalling is believed to define the mouse intestinal stem cell niche(s) from which adenomas arise. The aim of this study was to determine the relevance of these putative intestinal stem cell markers to human colorectal cancer.<h4>Design</h4>19 putative intestinal stem cell markers, including Ascl2 and Lgr5, were identified from published data and an evaluation of a human colorectal gene expression database. Associations between these genes were assessed by isotopic in situ hybridisation (ISH) in 57 colorectal adenocarcinomas. Multiplex fluorescent ISH and chromogenic non-isotopic ISH were performed to confirm expression patterns. The prognostic significance of Lgr5 was assessed in 891 colorectal adenocarcinomas.<h4>Results</h4>Ascl2 and Lgr5 were expressed in 85% and 74% of cancers respectively, and expression was positively correlated (p=0.003). Expression of Bmi1 was observed in 47% of cancers but was very weak in 98% of cases with expression. Both Ascl2 and/or Lgr5 were positively correlated with the majority of genes in the signature but neither was correlated with Cdk6, Gpx2, Olfm4 or Tnfrsf19. Lgr5 did not have prognostic significance.<h4>Conclusion</h4>These data suggest that 74-85% of colorectal cancers express a Lgr5/Ascl2 associated signature and support the hypothesis that they derive from Lgr5(+)/Ascl2(+) crypt stem cells, not Bmi1(+) stem cells. However, Olfm4 was not found to be a useful marker of Lgr5(+) cells in normal colon or tumours. In this large series, Lgr5 expression is not associated with increased tumour aggressiveness, as might be expected from a cancer stem cell marker.
The sarcomeric myosin gene, Myh7b, encodes an intronic microRNA, miR-499, which regulates cardiac and skeletal muscle biology, yet little is known about its transcriptional regulation. To identify the transcription factors involved in regulating Myh7b/miR-499 gene expression, we have mapped the transcriptional start sites and identified an upstream 6.2 kb region of the mouse Myh7b gene whose activity mimics the expression pattern of the endogenous Myh7b gene both in vitro and in vivo. Through promoter deletion analysis, we have mapped a distal E-box element and a proximal Ikaros site that are essential for Myh7b promoter activity in muscle cells. We show that the myogenic regulatory factors, MyoD, Myf5 and Myogenin, bind to the E-box, while a lymphoid transcription factor, Ikaros 4 (Eos), binds to the Ikaros motif. Further, we show that through physical interaction, MyoD and Eos form an active transcriptional complex on the chromatin to regulate the expression of the endogenous Myh7b/miR-499 gene in muscle cells. We also provide the first evidence that Eos can regulate expression of additional myosin genes (Myosin 1 and β-Myosin) via the miR-499/Sox6 pathway. Therefore, our results indicate a novel role for Eos in the regulation of the myofiber gene program.
Also flagged:restriction enzymesrestriction enzymeMse IdigestionP7P5
Journal Article2012-05-25No SnippetsTruong HT, Ramos AM, Yalcin F, de Ruiter M, van der Poel HJ, Huvenaars KH, Hogers RC, van Enckevort LJ, Janssen A, van Orsouw NJ, van Eijk MJ.
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Conventional marker-based genotyping platforms are widely available, but not without their limitations. In this context, we developed Sequence-Based Genotyping (SBG), a technology for simultaneous marker discovery and co-dominant scoring, using next-generation sequencing. SBG offers users several advantages including a generic sample preparation method, a highly robust genome complexity reduction strategy to facilitate de novo marker discovery across entire genomes, and a uniform bioinformatics workflow strategy to achieve genotyping goals tailored to individual species, regardless of the availability of a reference sequence. The most distinguishing features of this technology are the ability to genotype any population structure, regardless whether parental data is included, and the ability to co-dominantly score SNP markers segregating in populations. To demonstrate the capabilities of SBG, we performed marker discovery and genotyping in Arabidopsis thaliana and lettuce, two plant species of diverse genetic complexity and backgrounds. Initially we obtained 1,409 SNPs for arabidopsis, and 5,583 SNPs for lettuce. Further filtering of the SNP dataset produced over 1,000 high quality SNP markers for each species. We obtained a genotyping rate of 201.2 genotypes/SNP and 58.3 genotypes/SNP for arabidopsis (n = 222 samples) and lettuce (n = 87 samples), respectively. Linkage mapping using these SNPs resulted in stable map configurations. We have therefore shown that the SBG approach presented provides users with the utmost flexibility in garnering high quality markers that can be directly used for genotyping and downstream applications. Until advances and costs will allow for routine whole-genome sequencing of populations, we expect that sequence-based genotyping technologies such as SBG will be essential for genotyping of model and non-model genomes alike.
<h4>Background</h4>We previously reported that the USP17 deubiquitinating enzyme having hyaluronan binding motifs (HABMs) interacts with human SDS3 (suppressor of defective silencing 3) and specifically deubiquitinates Lys-63 branched polyubiquitination of SDS3 resulting in negative regulation of histone deacetylase (HDAC) activity in cancer cells. Furthermore, USP17 and SDS3 mutually interact with each other to block cell proliferation in HeLa cells but the mechanism for this inhibition in cell proliferation is not known. We wished to investigate whether the HABMs of USP17 were responsible for tumor suppression activity.<h4>Methodology/principal findings</h4>Similarly to USP17, we have identified that SDS3 also has three consecutive HABMs and shows direct binding with hyaluronan (HA) using cetylpyridinium chloride (CPC) assay. Additionally, HA oligosaccharides (6-18 sugar units) competitively block binding of endogenous HA polymer to HA binding proteins. Thus, administration of HA oligosaccharides antagonizes the interaction between HA and USP17 or SDS3. Interestingly, HABMs deleted USP17 showed lesser interaction with SDS3 but retain its deubiquitinating activity towards SDS3. The deletion of HABMs of USP17 could not alter its functional regulation on SDS3-associated HDAC activity. Furthermore, to explore whether HABMs in USP17 and SDS3 are responsible for the inhibition of cell proliferation, we investigated the effect of USP17 and SDS3-lacking HABMs on cell proliferation by soft agar, apoptosis, cell migration and cell proliferation assays.<h4>Conclusions</h4>Our results have demonstrated that these HABMs in USP17 and its substrate SDS3 are mainly involved in the inhibition of anchorage-independent tumor growth.
…Regulation of RKIP function by Helicobacter pylori in gastric cancer.…
Abstract)
…Forced overexpression of RKIP enhances apoptosis in H. pylori-infected cells, whereas RKIP RNA inhibition suppresses the induction of apoptosis by H. pylori infection.…
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Helicobacter pylori (H. pylori) is a gram-negative, spiral-shaped bacterium that infects more than half of the world's population and is a major cause of gastric adenocarcinoma. The mechanisms that link H. pylori infection to gastric carcinogenesis are not well understood. In the present study, we report that the Raf-kinase inhibitor protein (RKIP) has a role in the induction of apoptosis by H. pylori in gastric epithelial cells. Western blot and luciferase transcription reporter assays demonstrate that the pathogenicity island of H. pylori rapidly phosphorylates RKIP, which then localizes to the nucleus where it activates its own transcription and induces apoptosis. Forced overexpression of RKIP enhances apoptosis in H. pylori-infected cells, whereas RKIP RNA inhibition suppresses the induction of apoptosis by H. pylori infection. While inducing the phosphorylation of RKIP, H. pylori simultaneously targets non-phosphorylated RKIP for proteasome-mediated degradation. The increase in RKIP transcription and phosphorylation is abrogated by mutating RKIP serine 153 to valine, demonstrating that regulation of RKIP activity by H. pylori is dependent upon RKIP's S153 residue. In addition, H. pylori infection increases the expression of Snail, a transcriptional repressor of RKIP. Our results suggest that H. pylori utilizes a tumor suppressor protein, RKIP, to promote apoptosis in gastric cancer cells.
Also flagged:central nervous system infectioninfectionsCNS infectioninfectionInfectious diseases of thenervous system
Journal Article2012-05-25No SnippetsHo Dang Trung N, Le Thi Phuong T, Wolbers M, Nguyen Van Minh H, Nguyen Thanh V, Van MP, Thieu NT, Van TL, Song DT, Thi PL, Thi Phuong TN, Van CB, Tang V, Ngoc Anh TH, Nguyen D, Trung TP, Thi Nam LN, Kiem HT, Thi Thanh TN, Campbell J, Caws M, Day J, de Jong MD, Van Vinh CN, Van Doorn HR, Tinh HT, Farrar J, Schultsz C, VIZIONS CNS Infection Network.
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<h4>Background</h4>Infectious diseases of the central nervous system (CNS) remain common and life-threatening, especially in developing countries. Knowledge of the aetiological agents responsible for these infections is essential to guide empiric therapy and develop a rational public health policy. To date most data has come from patients admitted to tertiary referral hospitals in Asia and there is limited aetiological data at the provincial hospital level where most patients are seen.<h4>Methods</h4>We conducted a prospective Provincial Hospital-based descriptive surveillance study in adults and children at thirteen hospitals in central and southern Viet Nam between August 2007-April 2010. The pathogens of CNS infection were confirmed in CSF and blood samples by using classical microbiology, molecular diagnostics and serology.<h4>Results</h4>We recruited 1241 patients with clinically suspected infection of the CNS. An aetiological agent was identified in 640/1241 (52%) of the patients. The most common pathogens were Streptococcus suis serotype 2 in patients older than 14 years of age (147/617, 24%) and Japanese encephalitis virus in patients less than 14 years old (142/624, 23%). Mycobacterium tuberculosis was confirmed in 34/617 (6%) adult patients and 11/624 (2%) paediatric patients. The acute case fatality rate (CFR) during hospital admission was 73/617 (12%) in adults and to 42/624 (7%) in children.<h4>Conclusions</h4>Zoonotic bacterial and viral pathogens are the most common causes of CNS infection in adults and children in Viet Nam.
Also flagged:prostate cancerdeathC2orf43FOXP4GPRC6ARFX6
Journal Article2012-05-25✓ 4 SnippetsLong QZ, Du YF, Ding XY, Li X, Song WB, Yang Y, Zhang P, Zhou JP, Liu XG.
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…Association of the HFE (hemochromatosis) gene with prostate cancer [14] highlight the crosstalk between pathology of hemochromatosis and prostate cancer.…
Discussion)
…Association of theHFE(hemochromatosis) gene with…
<h4>Background</h4>Prostate cancer represents the leading cause of male death across the world. A recent genome-wide association study (GWAS) identified five novel susceptibility loci for prostate cancer in the Japanese population. This study is to replicate and fine map the potential association of these five loci with prostate cancer in the Chinese Han population.<h4>Methods</h4>In Phase I of the study, we tested the five single nucleotide polymorphisms (SNPs) which showed the strongest association evidence in the original GWAS in Japanese. The study sample consists of 1,169 Chinese Hans, comprising 483 patients and 686 healthy controls. Then in phase II, flanking SNPs of the successfully replicated SNPs in Phase I were genotyped and tested for association with prostate cancer to fine map those significant association signals.<h4>Results</h4>We successfully replicated the association of rs13385191 (located in the C2orf43 gene, P = 8.60×10(-5)), rs12653946 (P = 1.33×10(-6)), rs1983891 (FOXP4, P = 6.22×10(-5)), and rs339331 (GPRC6A/RFX6, P = 1.42×10(-5)) with prostate cancer. The most significant odds ratio (OR) was recorded as 1.41 (95% confidence interval 1.18-1.68) for rs12653946. Rs9600079 did not show significant association (P = 8.07×10(-2)) with prostate cancer in this study. The Phase II study refined these association signals, and identified several SNPs showing more significant association with prostate cancer than the very SNPs tested in Phase I.<h4>Conclusions</h4>Our results provide further support for association of the C2orf43, FOXP4, GPRC6A and RFX6 genes with prostate cancer in Eastern Asian populations. This study also characterized the novel loci reported in the original GWAS with more details. Further work is still required to determine the functional variations and finally clarify the underlying biological mechanisms.
Also flagged:polymerscarboxylic acidbindingSAcarbodiimidecancer
Journal Article2012-05-24No SnippetsZhang X, Yu J, Wu C, Jin Y, Rong Y, Ye F, Chiu DT.
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Semiconducting polymers with low-density side-chain carboxylic acid groups were synthesized to form stable, functionalized, and highly fluorescent polymer dots (Pdots). The influence of the molar fraction of hydrophilic side-chains on Pdot properties and performance was systematically investigated. Our results show that the density of side-chain carboxylic acid groups significantly affects Pdot stability, internal structure, fluorescence brightness, and nonspecific binding in cellular labeling. Fluorescence spectroscopy, single-particle imaging, and a dye-doping method were employed to investigate the fluorescence brightness and the internal structure of the Pdots. The results of these experiments indicate that semiconducting polymers with low density of side-chain functional groups can form stable, compact, and highly bright Pdots as compared to those with high density of hydrophilic side-chains. The functionalized polymer dots were conjugated to streptavidin (SA) by carbodiimide-catalyzed coupling and the Pdot-SA probes effectively and specifically labeled the cancer cell-surface marker Her2 in human breast cancer cells. The carboxylate-functionalized polymer could also be covalently modified with small functional molecules to generate Pdot probes for click chemistry-based bio-orthogonal labeling. This study presents a promising approach for further developing functional Pdot probes for biological applications.
…Serotonin transporter (5-HTT) genotype has been studied as a marker of HPA axis dysregulation and for predicting risk of psychopathology, with mixed findings.<h4>Objectives</h4>We stimulated the HPA axis with naloxone, an opioid receptor antagonist, to examine cortisol reactivity based on 5-HTT-linked polymorphic region (5-HTTLPR) genotypes.<h4>Methods</h4>Healthy community volunteers (N = 78) received intravenous (IV) placebo followed by sequential doses of IV naloxone (50, 100, 200, and 400 μg/kg) every 30 min.…
Abstract)
…Serotonin transporter (5-HTT) genotype has been…
Abstract)
…reactivity based on5-HTT-linked polymorphic region (5-…
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<h4>Rationale</h4>The serotonergic and opioidergic neurotransmitter systems are critical regulators of the hypothalamic-pituitary-adrenal (HPA) axis through their respective excitatory and inhibitory inputs. Serotonin transporter (5-HTT) genotype has been studied as a marker of HPA axis dysregulation and for predicting risk of psychopathology, with mixed findings.<h4>Objectives</h4>We stimulated the HPA axis with naloxone, an opioid receptor antagonist, to examine cortisol reactivity based on 5-HTT-linked polymorphic region (5-HTTLPR) genotypes.<h4>Methods</h4>Healthy community volunteers (N = 78) received intravenous (IV) placebo followed by sequential doses of IV naloxone (50, 100, 200, and 400 μg/kg) every 30 min. Plasma cortisol was measured every 15 min. Participants were genotyped for the long (L) and short (S) alleles of the 5-HTT gene and for rs25531 (A/G) in the 5-HTTLPR repetitive element and compared by the 5-HTTLPR/rs25531 genotype (triallele) and by the 5-HTTLPR genotype (biallele) classification.<h4>Results</h4>In triallele analyses, individuals with one or more L(A) alleles showed higher cortisol response to naloxone compared with individuals with no L(A) alleles. In biallele analyses, less robust effects were found, although individuals with two L alleles showed a higher cortisol response compared with other genotypes.<h4>Conclusions</h4>Naloxone blockade leads to a greater activation of the HPA axis among individuals with the L(A) allele. Including rs25531 in the analysis with the 5-HTTLPR genotype appears more sensitive in detecting genetic differences in naloxone-induced cortisol than when using only the 5-HTTLPR genotype. Future research should investigate the interactive effects between the serotonergic and opioidergic systems on HPA axis dysregulation and psychopathophysiology.
Also flagged:infectious diseaseiron deficiencyantibodiesmalariaCJDinfluenza
Journal Article2012-05-24✓ 2 SnippetsKleinman S, King MR, Busch MP, Murphy EL, Glynn SA, National Heart Lung Blood Institute Retrovirus Epidemiology Donor Study, Retrovirus Epidemiology Donor Study-II.
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…hemochromatosis…
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The Retrovirus Epidemiology Donor Study (REDS), conducted from 1989 to 2001, and the REDS-II, conducted from 2004 to 2012, were National Heart, Lung, and Blood Institute-funded, multicenter programs focused on improving blood safety and availability in the United States. The REDS-II also included international study sites in Brazil and China. The 3 major research domains of REDS/REDS-II have been infectious disease risk evaluation, blood donation availability, and blood donor characterization. Both programs have made significant contributions to transfusion medicine research methodology by the use of mathematical modeling, large-scale donor surveys, innovative methods of repository sample storage, and establishing an infrastructure that responded to potential emerging blood safety threats such as xenotropic murine leukemia virus-related virus. Blood safety studies have included protocols evaluating epidemiologic and/or laboratory aspects of human immunodeficiency virus, human T-lymphotropic virus 1/2, hepatitis C virus, hepatitis B virus, West Nile virus, cytomegalovirus, human herpesvirus 8, parvovirus B19, malaria, Creutzfeldt-Jakob disease, influenza, and Trypanosoma cruzi infections. Other analyses have characterized blood donor demographics, motivations to donate, factors influencing donor return, behavioral risk factors, donors' perception of the blood donation screening process, and aspects of donor deferral. In REDS-II, 2 large-scale blood donor protocols examined iron deficiency in donors and the prevalence of leukocyte antibodies. This review describes the major study results from over 150 peer-reviewed articles published by these 2 REDS programs. In 2011, a new 7-year program, the Recipient Epidemiology and Donor Evaluation Study-III, was launched. The Recipient Epidemiology and Donor Evaluation Study-III expands beyond donor-based research to include studies of blood transfusion recipients in the hospital setting and adds a third country, South Africa, to the international program.
Also flagged:Irongene expressiondegradationpoly(C)-binding protein 2PCBP2Dicer
Journal Article2012-05-24✓ 1 SnippetLi Y, Lin L, Li Z, Ye X, Xiong K, Aryal B, Xu Z, Paroo Z, Liu Q, He C, Jin P.
In-Text Gene Mentions
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…hemochromatosis…
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MicroRNAs (miRNAs) control gene expression by promoting degradation or repressing translation of target mRNAs. The components of the miRNA pathway are subject to diverse modifications that can modulate the abundance and function of miRNAs. Iron is essential for fundamental metabolic processes, and its homeostasis is tightly regulated. Here we identified iron chelators as a class of activator of the miRNA pathway that could promote the processing of miRNA precursors. We show that cytosolic iron could regulate the activity of the miRNA pathway through poly(C)-binding protein 2 (PCBP2). PCBP2 is associated with Dicer and promotes the processing of miRNA precursors. Cytosolic iron could modulate the association between PCBP2 and Dicer, as well as the multimerization of PCBP2 and its ability to bind to miRNA precursors, which can alter the processing of miRNA precursors. Our findings reveal a role of iron homeostasis in the regulation of miRNA biogenesis.
Also flagged:Ca(v)2.3 voltage-gated calcium channelcalmodulin-2voltage-activated Ca(2+) channelscarboxyCaM-2translation initiation
Journal Article2012-05-24No SnippetsKamp MA, Shakeri B, Tevoufouet EE, Krieger A, Henry M, Behnke K, Herzig S, Hescheler J, Radhakrishnan K, Parent L, Schneider T.
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Ca(v)2.3 containing voltage-activated Ca(2+) channels are expressed in excitable cells and trigger neurotransmitter and peptide-hormone release. Their expression remote from the fast release sites leads to the accumulation of presynaptic Ca(2+) which can both, facilitate and inhibit the influx of Ca(2+) ions through Ca(v)2.3. The facilitated Ca(2+) influx was recently related to hippocampal postsynaptic facilitation and long term potentiation. To analyze Ca(2+) mediated modulation of cellular processes more in detail, protein partners of the carboxy terminal tail of Ca(v)2.3 were identified by yeast-2-hybrid screening, leading in two human cell lines to the detection of a novel, extended and rarely occurring splice variant of calmodulin-2 (CaM-2), called CaM-2-extended (CaM-2-ext). CaM-2-ext interacts biochemically with the C-terminus of Ca(v)2.3 similar to the classical CaM-2 as shown by co-immunoprecipitation. Functionally, only CaM-2-ext reduces whole cell inward currents significantly. The insertion of the novel 46 nts long exon and the consecutive expression of CaM-2-ext must be dependent on a new upstream translation initiation site which is only rarely used in the tested human cell lines. The structure of the N-terminal extension is predicted to be more hydrophobic than the remaining CaM-2-ext protein, suggesting that it may help to dock it to the lipophilic membrane surrounding.
Chromosome pairing in meiotic prophase is a prerequisite for the high fidelity of chromosome segregation that haploidizes the genome prior to gamete formation. In the budding yeast Saccharomyces cerevisiae, as in most multicellular eukaryotes, homologous pairing at the cytological level reflects the contemporaneous search for homology at the molecular level, where DNA double-strand broken ends find and interact with templates for repair on homologous chromosomes. Synapsis (synaptonemal complex formation) stabilizes pairing and supports DNA repair. The bouquet stage, where telomeres have formed a transient single cluster early in meiotic prophase, and telomere-promoted rapid meiotic prophase chromosome movements (RPMs) are prominent temporal correlates of pairing and synapsis. The bouquet has long been thought to contribute to the kinetics of pairing, but the individual roles of bouquet and RPMs are difficult to assess because of common dependencies. For example, in budding yeast RPMs and bouquet both require the broadly conserved SUN protein Mps3 as well as Ndj1 and Csm4, which link telomeres to the cytoskeleton through the intact nuclear envelope. We find that mutants in these genes provide a graded series of RPM activity: wild-type>mps3-dCC>mps3-dAR>ndj1Δ>mps3-dNT = csm4Δ. Pairing rates are directly correlated with RPM activity even though only wild-type forms a bouquet, suggesting that RPMs promote homologous pairing directly while the bouquet plays at most a minor role in Saccharomyces cerevisiae. A new collision trap assay demonstrates that RPMs generate homologous and heterologous chromosome collisions in or before the earliest stages of prophase, suggesting that RPMs contribute to pairing by stirring the nuclear contents to aid the recombination-mediated homology search.
…channel 6 (TRPC6),Densin, and membrane-associated guan…
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Aims. Proteinuria not only is a sign of kidney damage, but also is involved in the progression of renal diseases as an independent pathologic factor. Clinically, glomerular proteinuria is most commonly observed, which relates to structural and functional anomalies in the glomerular filtration barrier. The aim of this paper was to describe the pathogenesis of glomerular proteinuria. Data Sources. Articles on glomerular proteinuria retrieved from Pubmed and MEDLINE in the recent 5 years were reviewed. Results. The new understanding of the roles of glomerular endothelial cells and the glomerular basement membrane (GBM) in the pathogenesis of glomerular proteinuria was gained. The close relationships of slit diaphragm (SD) molecules such as nephrin, podocin, CD2-associated protein (CD2AP), a-actinin-4, transient receptor potential cation channel 6 (TRPC6), Densin and membrane-associated guanylate kinase inverted 1 (MAGI-1), α3β1 integrin, WT1, phospholipase C epsilon-1 (PLCE1), Lmx1b, and MYH9, and mitochondrial disorders and circulating factors in the pathogenesis of glomerular proteinuria were also gradually discovered. Conclusion. Renal proteinuria is a manifestation of glomerular filtration barrier dysfunction. Not only glomerular endothelial cells and GBM, but also the glomerular podocytes and their SDs play an important role in the pathogenesis of glomerular proteinuria.
Also flagged:dissectionischemic strokeextracellular matrixorganizationtransforming growth factor beta(TGF)-beta receptor
Journal Article2012-05-23No SnippetsGrond-Ginsbach C, Chen B, Pjontek R, Wiest T, Jiang Y, Burwinkel B, Tchatchou S, Krawczak M, Schreiber S, Brandt T, Kloss M, Arnold ML, Hemminki K, Lichy C, Lyrer PA, Hausser I, Engelter ST.
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Cervical artery dissection (CeAD) occurs in healthy young individuals and often entails ischemic stroke. Skin biopsies from most CeAD-patients show minor connective tissue alterations. We search for rare genetic deletions and duplication that may predispose to CeAD. Forty-nine non-traumatic CeAD-patients with electron microscopic (EM) alterations of their dermal connective tissue (EM+ patients) and 21 patients with normal connective tissue in skin biopsies (EM- patients) were analyzed. Affymetrix 6.0 microarrays (Affymetrix) from all patients were screened for copy number variants (CNVs). CNVs absent from 403 control subjects and from 2402 published disease-free individuals were considered as CeAD-associated. The genetic content of undentified CNVs was analyzed by means of the Gene Ontology (GO) Term Mapper to detect associations with biological processes. In 49 EM+ patients we identified 13 CeAD-associated CNVs harboring 83 protein-coding genes. In 21 EM- patients we found five CeAD-associated CNVs containing only nine genes (comparison of CNV gene density between the groups: Mann-Whitney P=0.039). Patients' CNVs were enriched for genes involved in extracellular matrix organization (COL5A2, COL3A1, SNTA1, P=0.035), collagen fibril organization COL5A2, COL3A1, (P=0.0001) and possibly for genes involved in transforming growth factor beta (TGF)-beta receptor signaling pathway (COL3A1, DUPS22, P=0.068). We conclude that rare genetic variants may contribute to the pathogenesis of CeAD, in particular in patients with a microscopic connective tissue phenotype.
Also flagged:ribosomesribosomeribozymepost-translational modificationsribosomal proteinsgene expression
Journal Article2012-05-23No SnippetsXue S, Barna M.
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Historically, the ribosome has been viewed as a complex ribozyme with constitutive rather than intrinsic regulatory capacity in mRNA translation. However, emerging studies reveal that ribosome activity may be highly regulated. Heterogeneity in ribosome composition resulting from differential expression and post-translational modifications of ribosomal proteins, ribosomal RNA (rRNA) diversity and the activity of ribosome-associated factors may generate 'specialized ribosomes' that have a substantial impact on how the genomic template is translated into functional proteins. Moreover, constitutive components of the ribosome may also exert more specialized activities by virtue of their interactions with specific mRNA regulatory elements such as internal ribosome entry sites (IRESs) or upstream open reading frames (uORFs). Here we discuss the hypothesis that intrinsic regulation by the ribosome acts to selectively translate subsets of mRNAs harbouring unique cis-regulatory elements, thereby introducing an additional level of regulation in gene expression and the life of an organism.
Also flagged:autophagyHuntington diseaseHDpolyglutamineHuntingtindementia
Journal Article2012-05-23✓ 2 SnippetsVidal RL, Hetz C.
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Abstract)
…Huntington disease (HD) is caused by an extended polyglutamine [poly(Q)] stretch in the Huntingtin (HTT) protein, and is associated with the accumulation of intracellular protein aggregates, onset of progressive chorea, psychiatric symptoms and dementia.…
Abstract)
…in the Huntingtin (HTT) protein, and is…
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Huntington disease (HD) is caused by an extended polyglutamine [poly(Q)] stretch in the Huntingtin (HTT) protein, and is associated with the accumulation of intracellular protein aggregates, onset of progressive chorea, psychiatric symptoms and dementia. Although the mechanism underlying the pathological effects of mutant HTT (mHTT) remains highly controversial, accumulating evidence suggest that protein-folding stress at the endoplasmic reticulum (ER) may contribute to mHTT-mediated degeneration. ER stress is alleviated by the activation of an adaptive reaction known as the unfolded protein response (UPR), whereas chronic ER stress triggers apoptosis by the same pathway. However, most of the studies linking ER stress with HD in vivo are correlative. UPR signaling is initiated by the activation of at least three distinct stress sensors located at the ER membrane known as ERN1/IRE1α, EIF2AK3/PERK and ATF6. These stress sensors control the expression of specialized transcription factors that modulate the upregulation of a variety of target genes involved in folding, protein quality control, autophagy and protein synthesis.
Also flagged:RNA-binding protein nucleolinNucleolinnucleolusnucleoplasmcytoplasmmembrane
Journal Article2012-05-23No SnippetsAbdelmohsen K, Gorospe M.
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Nucleolin is a multifunctional protein localized primarily in the nucleolus, but also found in the nucleoplasm, cytoplasm and cell membrane. It is involved in several aspects of DNA metabolism, and participates extensively in RNA regulatory mechanisms, including transcription, ribosome assembly, mRNA stability and translation, and microRNA processing. Nucleolin's implication in disease is linked to its ability to associate with target RNAs via its four RNA-binding domains and its arginine/glycin-rich domain. By modulating the post-transcriptional fate of target mRNAs, which typically bear AU-rich and/or G-rich elements, nucleolin has been linked to cellular events that influence disease, notably cell proliferation and protection against apoptotic death. Through its diverse RNA functions, nucleolin is increasingly implicated in pathological processes, particularly cancer and viral infection. Here, we review the RNA-binding activities of nucleolin, its influence on gene expression patterns, and its impact upon diseases. We also discuss the rising interest in targeting nucleolin therapeutically.
Genome-wide association studies have identified a number of genes associated with human body weight. While some of these genes are large fields within obesity research, such as MC4R, POMC, FTO and BDNF, the majority do not have a clearly defined functional role explaining why they may affect body weight. Here, we searched biological databases and discovered 33 additional genes associated with human obesity (CADM2, GIPR, GPCR5B, LRP1B, NEGR1, NRXN3, SH2B1, FANCL, GNPDA2, HMGCR, MAP2K5, NUDT3, PRKD1, QPCTL, TNNI3K, MTCH2, DNAJC27, SLC39A8, MTIF3, RPL27A, SEC16B, ETV5, HMGA1, TFAP2B, TUB, ZNF608, FAIM2, KCTD15, LINGO2, POC5, PTBP2, TMEM18, TMEM160). We find that the majority have orthologues in distant species, such as D. melanogaster and C. elegans, suggesting that they are important for the biology of most bilateral species. Intriguingly, signalling cascade genes and transcription factors are enriched among these obesity genes, and several of the genes show properties that could be useful for potential drug discovery. In this review, we demonstrate how information from several distant model species, interactomics and signalling pathway analysis represents an important way to better understand the functional diversity of the surprisingly high number of molecules that seem to be important for human obesity.
Also flagged:Huntington diseaseHDnucleusneurodegenerative diseasecognitive impairmentsdeath
Journal Article2012-05-23No SnippetsAntonsen BT, Jiang Y, Veraart J, Qu H, Nguyen HP, Sijbers J, von Hörsten S, Johnson GA, Leergaard TB.
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Rodent models of Huntington disease (HD) are valuable tools for investigating HD pathophysiology and evaluating new therapeutic approaches. Non-invasive characterization of HD-related phenotype changes is important for monitoring progression of pathological processes and possible effects of interventions. The first transgenic rat model for HD exhibits progressive late-onset affective, cognitive, and motor impairments, as well as neuropathological features reflecting observations from HD patients. In this report, we contribute to the anatomical phenotyping of this model by comparing high-resolution ex vivo DTI measurements obtained in aged transgenic HD rats and wild-type controls. By region of interest analysis supplemented by voxel-based statistics, we find little evidence of atrophy in basal ganglia regions, but demonstrate altered DTI measurements in the dorsal and ventral striatum, globus pallidus, entopeduncular nucleus, substantia nigra, and hippocampus. These changes are largely compatible with DTI findings in preclinical and clinical HD patients. We confirm earlier reports that HD rats express a moderate neuropathological phenotype, and provide evidence of altered DTI measures in specific HD-related brain regions, in the absence of pronounced morphometric changes.
Also flagged:major histocompatibility complex classes IinfectionorganizationU94Repmajor histocompatibility complex
Journal Article2012-05-23✓ 1 SnippetZhang H, Todd S, Tachedjian M, Barr JA, Luo M, Yu M, Marsh GA, Crameri G, Wang LF.
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Text
…HFE…
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Herpesviruses or herpesviral sequences have been identified in various bat species. Here, we report the isolation, cell tropism, and complete genome sequence of a novel betaherpesvirus from the bat Miniopterus schreibersii (MsHV). In primary cell culture, MsHV causes cytopathic effects (CPE) and reaches peak virus production 2 weeks after infection. MsHV was found to infect and replicate less efficiently in a feline kidney cell, CRFK, and failed to replicate in 13 other cell lines tested. Sequencing of the MsHV genome using the 454 system, with a 224-fold coverage, revealed a genome size of 222,870 bp. The genome was extensively analyzed in comparison to those of related viruses. Of the 190 predicted open reading frames (ORFs), 40 were identified as herpesvirus core genes. Among 93 proteins with identifiable homologues in tree shrew herpesvirus (THV), human cytomegalovirus (HCMV), or rat cytomegalovirus (RCMV), most had highest sequence identities with THV counterparts. However, the MsHV genome organization is colinear with that of RCMV rather than that of THV. The following unique features were discovered in the MsHV genome. One predicted protein, B125, is similar to human herpesvirus 6 (HHV-6) U94, a homologue of the parvovirus Rep protein. For the unique ORFs, 7 are predicted to encode major histocompatibility complex (MHC)-related proteins, 2 to encode MHC class I homologues, and 3 to encode MHC class II homologues; 4 encode the homologues of C-type lectin- or natural killer cell lectin-like receptors;, and the products of a unique gene family, the b149 family, of 16 members, have no significant sequence identity with known proteins but exhibit immunoglobulin-like beta-sandwich domains revealed by three-dimensional (3D) structural prediction. To our knowledge, MsHV is the first virus genome known to encode MHC class II homologues.
Also flagged:Huntingtin Interacting Protein 14palmitoyl acyl transferasePATHuntington DiseaseHDsynapse
Journal Article2012-05-23✓ 5 SnippetsYoung FB, Franciosi S, Spreeuw A, Deng Y, Sanders S, Tam NC, Huang K, Singaraja RR, Zhang W, Bissada N, Kay C, Hayden MR.
In-Text Gene Mentions
Abstract)
…Huntingtin Interacting Protein 14 (HIP14) is a palmitoyl acyl transferase (PAT) that was first identified due to altered interaction with mutant huntingtin, the protein responsible for Huntington Disease (HD).…
Introduction)
…More recently, the major site of palmitoylation of HTT was identified as cysteine 214 and mutation of this site, rendering HTT non-palmitoylatable, increases inclusion formation and neuronal toxicity.…
Discussion)
…Previous studies demonstrated rescue of the murine huntingtin (Hdh−/−) knockout phenotype by human HTT despite only 90% conserved amino acid identity [29], [44].…
Introduction)
…The enrichment of HIP14 in the brain, its expression in the medium spiny neurons primarily affected in HD, and its co-localization with HTT are all features supportive of a role for HIP14 in the pathogenesis of HD [18].…
Introduction)
…However, HIP14 was selected for further study because its interaction with HTT is reduced in the presence of the mutation responsible for HD [18], resulting in less robust palmitoylation of HIP14 substrates [21] fulfilling genetic criteria for having a potential relationship to the disease.…
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Huntingtin Interacting Protein 14 (HIP14) is a palmitoyl acyl transferase (PAT) that was first identified due to altered interaction with mutant huntingtin, the protein responsible for Huntington Disease (HD). HIP14 palmitoylates a specific set of neuronal substrates critical at the synapse, and downregulation of HIP14 by siRNA in vitro results in increased cell death in neurons. We previously reported that mice lacking murine Hip14 (Hip14-/-) share features of HD. In the current study, we have generated human HIP14 BAC transgenic mice and crossed them to the Hip14-/- model in order to confirm that the defects seen in Hip14-/- mice are in fact due to loss of Hip14. In addition, we sought to determine whether human HIP14 can provide functional compensation for loss of murine Hip14. We demonstrate that despite a relative low level of expression, as assessed via Western blot, BAC-derived human HIP14 compensates for deficits in neuropathology, behavior, and PAT enzyme function seen in the Hip14-/- model. Our findings yield important insights into HIP14 function in vivo.
…Our results suggests that full length, non-aggregated polyQ-expanded Htt blocks the effective induction of the heat shock response under stress conditions and may thus trigger the accumulation of cellular damage during the course of HD pathogenesis.…
Abstract)
…The molecular mechanisms by which polyglutamine (polyQ)-expanded huntingtin (Htt) causes neurodegeneration in Huntington's disease (HD) remain unclear.…
Discussion)
…Clearly, a deeper understanding of the role of HSF1, the heat shock response, and cellular stress and polyQ-expanded Htt in HD is required to validate these musings.…
Introduction)
…Even though the genetic basis of HD is clear, the cellular mechanisms by which polyQ-expanded Htt causes the dysfunction and the demise of neurons remains perplexing.…
Results)
…These results demonstrated that the polyQ-expanded Htt cells are highly sensitized to MG132 and radicicol treatment.…
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The molecular mechanisms by which polyglutamine (polyQ)-expanded huntingtin (Htt) causes neurodegeneration in Huntington's disease (HD) remain unclear. The malfunction of cellular proteostasis has been suggested as central in HD pathogenesis and also as a target of therapeutic interventions for the treatment of HD. We present results that offer a previously unexplored perspective regarding impaired proteostasis in HD. We find that, under non-stress conditions, the proteostatic capacity of cells expressing full length polyQ-expanded Htt is adequate. Yet, under stress conditions, the presence of polyQ-expanded Htt impairs the heat shock response, a key component of cellular proteostasis. This impaired heat shock response results in a reduced capacity to withstand the damage caused by cellular stress. We demonstrate that in cells expressing polyQ-expanded Htt the levels of heat shock transcription factor 1 (HSF1) are reduced, and, as a consequence, these cells have an impaired a heat shock response. Also, we found reduced HSF1 and HSP70 levels in the striata of HD knock-in mice when compared to wild-type mice. Our results suggests that full length, non-aggregated polyQ-expanded Htt blocks the effective induction of the heat shock response under stress conditions and may thus trigger the accumulation of cellular damage during the course of HD pathogenesis.
Also flagged:tumorbreast carcinomadegradationcancerbreast cancergene expressions
Journal Article2012-05-23No SnippetsTseng CW, Huang HC, Shih AC, Chang YY, Hsu CC, Chang JY, Li WH, Juan HF.
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microRNAs (miRNAs) cause mRNA degradation or translation suppression of their target genes. Previous studies have found direct involvement of miRNAs in cancer initiation and progression. Artificial miRNAs, designed to target single or multiple genes of interest, provide a new therapeutic strategy for cancer. This study investigates the anti-tumor effect of a novel artificial miRNA, miR P-27-5p, on breast cancer. In this study, we reveal that miR P-27-5p downregulates the differential gene expressions associated with the protein modification process and regulation of cell cycle in T-47D cells. Introduction of this novel artificial miRNA, miR P-27-5p, into breast cell lines inhibits cell proliferation and induces the first "gap" phase (G1) cell cycle arrest in cancer cell lines but does not affect normal breast cells. We further show that miR P-27-5p targets the 3'-untranslated mRNA region (3'-UTR) of cyclin-dependent kinase 4 (CDK4) and reduces both the mRNA and protein level of CDK4, which in turn, interferes with phosphorylation of the retinoblastoma protein (RB1). Overall, our data suggest that the effects of miR p-27-5p on cell proliferation and G1 cell cycle arrest are through the downregulation of CDK4 and the suppression of RB1 phosphorylation. This study opens avenues for future therapies targeting breast cancer.
Implants formed of metals, bioceramics, or polymers may provide an alternative to autografts for treating large bone defects. However, limitations to each material motivate the examination of composites to capitalize on the beneficial aspects of individual components and to address the need for conferring bioactive behavior to the polymer matrix. We hypothesized that the inclusion of different bioceramics in a ceramic-polymer composite would alter the physical properties of the implant and the cellular osteogenic response. To test this, composite scaffolds formed from poly(lactide-co-glycolide) (PLG) and either hydroxyapatite (HA), β-tricalcium phosphate (TCP), or bioactive glass (Bioglass 45S®, BG) were fabricated, and the physical properties of each scaffold were examined. We quantified cell proliferation by DNA content, osteogenic response of human osteoblasts (NHOsts) to composite scaffolds by alkaline phosphatase (ALP) activity, and changes in gene expression by qPCR. Compared to BG-PLG scaffolds, HA-PLG and TCP-PLG composite scaffolds possessed greater compressive moduli. NHOsts on BG-PLG substrates exhibited higher ALP activity than those on control, HA-, or TCP-PLG scaffolds after 21 days, and cells on composites exhibited a 3-fold increase in ALP activity between 7 and 21 days versus a minimal increase on control scaffolds. Compared to cells on PLG controls, RUNX2 expression in NHOsts on composite scaffolds was lower at both 7 and 21 days, while expression of genes encoding for bone matrix proteins (COL1A1 and SPARC) was higher on BG-PLG scaffolds at both time points. These data demonstrate the importance of selecting a ceramic when fabricating composites applied for bone healing.
Also flagged:thyroidcolon cancersautoantibodiescancertumorantibody
Journal Article2012-05-22✓ 2 SnippetsKiyamova R, Garifulin O, Gryshkova V, Kostianets O, Shyian M, Gout I, Filonenko V.
In-Text Gene Mentions
Abstract)
…<h4>Background</h4>Autoantibodies, which are produced against tumor-associated antigens, are potential tumor markers and attract a growing interest for cancer detection, differential diagnostics and prognosis.<h4>Objective</h4>To evaluate the diagnostic significance of 40 antigens identified by immunoscreening of cDNA libraries from thyroid and colon cancers by allogenic screening with different tumor types patients' sera.<h4>Method</h4>Plaque-spot serological assay.<h4>Results</h4>Increased frequency of antibody response in sera of cancer patients compared with that of healthy donors was shown toward 14 antigens, 8 of which (CG016, BTN3A3, FKBP4, XRCC4, TSGA2, ACTR1A, FXYD3 and CTSH) have revealed exclusively cancer-related serological profile.<h4>Conclusion</h4>Allogenic screening of 40 SEREX-antigens with sera from cancer patients and healthy donors allowed us to reveal 14 antigens with potential diagnostic significance.…
Abstract)
…of which (CG016,BTN3A3, FKBP4, XRCC4, TSGA2,…
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<h4>Background</h4>Autoantibodies, which are produced against tumor-associated antigens, are potential tumor markers and attract a growing interest for cancer detection, differential diagnostics and prognosis.<h4>Objective</h4>To evaluate the diagnostic significance of 40 antigens identified by immunoscreening of cDNA libraries from thyroid and colon cancers by allogenic screening with different tumor types patients' sera.<h4>Method</h4>Plaque-spot serological assay.<h4>Results</h4>Increased frequency of antibody response in sera of cancer patients compared with that of healthy donors was shown toward 14 antigens, 8 of which (CG016, BTN3A3, FKBP4, XRCC4, TSGA2, ACTR1A, FXYD3 and CTSH) have revealed exclusively cancer-related serological profile.<h4>Conclusion</h4>Allogenic screening of 40 SEREX-antigens with sera from cancer patients and healthy donors allowed us to reveal 14 antigens with potential diagnostic significance. These antigens and their cognate autoantibodies could be considered as valuable targets for further analysis as potential cancer biomarkers.
Also flagged:asneurodegenerative disordersspinal cord injuriesof thesystemtranscription factors
Journal Article2012-05-22No SnippetsAbdullah AI, Pollock A, Sun T.
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Cell fate reprogramming makes possible the generation of new cell types from healthy adult cells to replace those lost or damaged in disease. Additionally, reprogramming patient cells into specific cell types allows for drug screening and the development of new therapeutic tools. Generation of new neurons is of particular interest because of the potential to treat diseases of the nervous system, such as neurodegenerative disorders and spinal cord injuries, with cell replacement therapy. Recent advances in cell fate reprogramming have led to the development of novel methods for the direct conversion of fibroblasts into neurons and neural stem cells. This review will highlight the advantages of these new methods over neuronal induction from embryonic stem cells and induced pluripotent stem cells, as well as outline the limitations and the potential for future applications.
Also flagged:lipoproteinglucoselipiddiabetesIRgenetic syndrome
Journal Article2012-05-22No SnippetsMagge SN, Prasad D, Koren D, Gallagher PR, Mohler ER, Stettler N, Levitt Katz LE, Rader DJ.
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<h4>Objective</h4>To compare lipoprotein profiles of prediabetic to normoglycemic obese adolescents.<h4>Study design</h4>Cross-sectional study of 95 obese, pubertal adolescents (12-17 years), who underwent oral glucose tolerance test, lipid panel, and lipoprotein subclass particle analysis (nuclear magnetic resonance spectroscopy). Univariate and linear regression analyses compared prediabetic and normoglycemic groups.<h4>Results</h4>Of 95 obese adolescents enrolled in the study, 22.1% (n = 21) had prediabetes. They were similar to normoglycemic adolescents (n = 74) in age, race, body mass index, standard lipids, total low-density lipoprotein particles (LDL-P), and total high-density lipoprotein particles (HDL-P). However, prediabetics had higher concentrations of small LDL-P (714.0 ± 288.0 vs 537.7 ± 266.5 nmol/L, P = .01) and smaller LDL-P size (20.73 ± 0.41 vs 21.18 ± 0.65 nm, P = .003), than normoglycemic youth. Prediabetics had higher small HDL-P (18.5 ± 3.8 vs 16.6 ± 3.9 umol/L, P = .046), lower large HDL-P (4.49 ± 2.0 vs 6.32 ± 2.6 umol/L, P = .004), and smaller HDL-P size (8.73 ± 0.31 vs 9.01 ± 0.39 nm, P = .003). After adjusting for demographics, Tanner stage, and body mass index using multiple linear regression, all differences remained significant except for small HDL-P. After additional adjustment for Homeostasis Model Assessment-Insulin Resistance Index, only LDL-P size difference remained significant.<h4>Conclusion</h4>Obese prediabetic adolescents have a significantly more atherogenic lipoprotein profile compared with obese normoglycemic peers. Prediabetic adolescents may benefit from more aggressive interventions to decrease future cardiovascular risk.
The extracellular matrix (ECM) in the central nervous system actively orchestrates and modulates changes in neural structure and function in response to experience, after injury, during disease, and with changes in neuronal activity. A component of the multi-protein, ECM aggregate in brain, the chondroitin sulfate (CS)-bearing proteoglycans (PGs) known as lecticans, inhibit neurite outgrowth, alter dendritic spine shape, elicit closure of critical period plasticity, and block target reinnervation and functional recovery after injury as the major component of a glial scar. While removal of the CS chains from lecticans with chondroitinase ABC improves plasticity, proteolytic cleavage of the lectican core protein may change the conformation of the matrix aggregate and also modulate neural plasticity. This review centers on the roles of the lecticans and the endogenous metalloproteinase families that proteolytically cleave lectican core proteins, the matrix metalloproteinases (MMPs) and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTSs), in neural plasticity. These extracellular metalloproteinases modulate structural neural plasticity-including changes in neurite outgrowth and dendritic spine remodeling-and synaptic plasticity. Some of these actions have been demonstrated to occur via cleavage of the PG core protein. Other actions of the proteases include cleavage of non-matrix substrate proteins, whereas still other actions may occur directly at the cell surface without proteolytic cleavage. The data convincingly demonstrate that metalloproteinases modulate physiological and pathophysiological neural plasticity.
Also flagged:transcription factorshistone acetyltransferaseshistone deacetylasesHDACsdegradationubiquitin ligase
Journal Article2012-05-22✓ 1 SnippetAlamdari N, Aversa Z, Castillero E, Hasselgren PO.
In-Text Gene Mentions
Title)
…of Huntingtin protein (Htt).…
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We review recent evidence that acetylation and deacetylation of cellular proteins, including transcription factors and nuclear cofactors, may be involved in the regulation of muscle mass. The level of protein acetylation is balanced by histone acetyltransferases (HATs) and histone deacetylases (HDACs) and studies suggest that this balance is perturbed in muscle wasting. Hyperacetylation of transcription factors and nuclear cofactors regulating gene transcription in muscle wasting may influence muscle mass. In addition, hyperacetylation may render proteins susceptible to degradation by different mechanisms, including intrinsic ubiquitin ligase activity exerted by HATs and by dissociation of proteins from cellular chaperones. In recent studies, inhibition of p300/HAT expression and activity and stimulation of SIRT1-dependent HDAC activity reduced glucocorticoid-induced catabolic response in skeletal muscle, providing further evidence that hyperacetylation plays a role in muscle wasting. It should be noted, however, that although several studies advocate a role of hyperacetylation in muscle wasting, apparently contradictory results have also been reported. For example, muscle atrophy caused by denervation or immobilization may be associated with reduced, rather than increased, protein acetylation. In addition, whereas hyperacetylation results in increased degradation of certain proteins, other proteins may be stabilized by increased acetylation. Thus, the role of acetylation and deacetylation in the regulation of muscle mass may be both condition- and protein-specific. The influence of HATs and HDACs on the regulation of muscle mass, as well as methods to modulate protein acetylation, is an important area for continued research aimed at preventing and treating muscle wasting.
Stereochemistry is a key aspect of molecular recognition for biological systems. As such, receptors and enzymes are often highly stereospecific, only recognizing one stereoisomer of a ligand. Recently, the quorum sensing signaling molecules used by the nosocomial opportunistic pathogen, Acinetobacter baumannii, were identified, and the primary signaling molecule isolated from this species was N-(3-hydroxydodecanoyl)-L-homoserine lactone. A plethora of bacterial species have been demonstrated to utilize 3-hydroxy-acylhomoserine lactone autoinducers, and in virtually all cases, the (R)-stereoisomer was identified as the natural ligand and exhibited greater autoinducer activity than the corresponding (S)-stereoisomer. Using chemical synthesis and biochemical assays, we have uncovered a case of stereochemical insignificance in A. baumannii and provide a unique example where stereochemistry appears nonessential for acylhomoserine lactone-mediated quorum sensing signaling. Based on previously reported phylogenetic studies, we suggest that A. baumannii has evolutionarily adopted this unique, yet promiscuous quorum sensing system to ensure its survival, particularly in the presence of other proteobacteria.
Also flagged:ironmetabolismagingAlzheimer's diseaseneurodegenerative disordersAD
Journal Article2012-05-22✓ 4 SnippetsMesquita SD, Ferreira AC, Sousa JC, Santos NC, Correia-Neves M, Correia-Neves M, Sousa N, Palha JA, Marques F.
In-Text Gene Mentions
S I O 001029)
…These epithelial cells express receptors that are directly or indirectly involved in iron uptake, such as transferrin receptors type 1 and 2 (TFR1 and 2) (1) as well as hemochromatosis (HFE) protein that is able to bind to TFR2; (2) Duodenal cytochrome B (DCYTB) and divalent metal transporter 1 (DMT1) are present in the basolateral membrane and, respectively, reduce ferric iron (Fe3+) to ferrous iron (Fe2+) and transport it into the cell; (3) An iron exporter localized in the apical face of the CP epithelial cell, ferroportin (FPN), can be internalized and degraded through the action of hepcidin (HAMP); (4) a hormone also produced by the CP in response to specific conditions, such as an inflammatory stimulus, through STAT3 and SMAD4 transcription factors.…
Introduction)
…conditions, namely HJV,HFE, TFR2, FTH, FTL,…
Introduction)
…as well ashemochromatosis(HFE) protein that…
Introduction)
…well as hemochromatosis (HFE) protein that is…
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Iron is essential for mammalian cellular homeostasis. However, in excess, it promotes free radical formation and is associated with aging-related progressive deterioration and with neurodegenerative disorders such as Alzheimer's disease (AD). There are no mechanisms to excrete iron, which makes iron homeostasis a very tightly regulated process at the level of the intestinal absorption. Iron is believed to reach the brain through receptor-mediated endocytosis of iron-bound transferrin by the brain barriers, the blood-cerebrospinal fluid (CSF) barrier, formed by the choroid plexus (CP) epithelial cells and the blood-brain barrier (BBB) formed by the endothelial cells of the brain capillaries. Importantly, the CP epithelial cells are responsible for producing most of the CSF, the fluid that fills the brain ventricles and the subarachnoid space. Recently, the finding that the CP epithelial cells display all the machinery to locally control iron delivery into the CSF may suggest that the general and progressive senescence of the CP may be at the basis of the impairment of regional iron metabolism, iron-mediated toxicity, and the increase in inflammation and oxidative stress that occurs with aging and, particularly, in AD.
Also flagged:neurodegenerative disorderHuntingtinHDneurological disorderscytoplasmicvacuoles
Journal Article2012-05-21✓ 5 SnippetsJuopperi TA, Kim WR, Chiang CH, Yu H, Margolis RL, Ross CA, Ming GL, Song H.
In-Text Gene Mentions
Introduction)
…of huntingtin (HTT), which results…
Introduction)
…N-terminal of theHTTprotein [ 3…
Introduction)
…Although the wild-typeHTTprotein is ubiquitously…
Introduction)
…of the mutantHTTprotein in neurons,…
Methods)
…mutant and wild-typeHTTproteins in fibroblasts,…
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<h4>Background</h4>Huntington's Disease (HD) is a devastating neurodegenerative disorder that clinically manifests as motor dysfunction, cognitive impairment and psychiatric symptoms. There is currently no cure for this progressive and fatal disorder. The causative mutation of this hereditary disease is a trinucleotide repeat expansion (CAG) in the Huntingtin gene that results in an expanded polyglutamine tract. Multiple mechanisms have been proposed to explain the preferential striatal and cortical degeneration that occurs with HD, including non-cell-autonomous contribution from astrocytes. Although numerous cell culture and animal models exist, there is a great need for experimental systems that can more accurately replicate the human disease. Human induced pluripotent stem cells (iPSCs) are a remarkable new tool to study neurological disorders because this cell type can be derived from patients as a renewable, genetically tractable source for unlimited cells that are difficult to acquire, such as neurons and astrocytes. The development of experimental systems based on iPSC technology could aid in the identification of molecular lesions and therapeutic treatments.<h4>Results</h4>We derived iPSCs from a father with adult onset HD and 50 CAG repeats (F-HD-iPSC) and his daughter with juvenile HD and 109 CAG repeats (D-HD-iPSC). These disease-specific iPSC lines were characterized by standard assays to assess the quality of iPSC lines and to demonstrate their pluripotency. HD-iPSCs were capable of producing phenotypically normal, functional neurons in vitro and were able to survive and differentiate into neurons in the adult mouse brain in vivo after transplantation. Surprisingly, when HD-iPSCs were directed to differentiate into an astrocytic lineage, we observed the presence of cytoplasmic, electron clear vacuoles in astrocytes from both F-HD-iPSCs and D-HD-iPSCs, which were significantly more pronounced in D-HD-astrocytes. Remarkably, the vacuolation in diseased astrocytes was observed under basal culture conditions without additional stressors and increased over time. Importantly, similar vacuolation phenotype has also been observed in peripheral blood lymphocytes from individuals with HD. Together, these data suggest that vacuolation may be a phenotype associated with HD.<h4>Conclusions</h4>We have generated a unique in vitro system to study HD pathogenesis using patient-specific iPSCs. The astrocytes derived from patient-specific iPSCs exhibit a vacuolation phenotype, a phenomenon previously documented in primary lymphocytes from HD patients. Our studies pave the way for future mechanistic investigations using human iPSCs to model HD and for high-throughput therapeutic screens.
Also flagged:cancerchromatinbindingtranscription factorstranslationalnuclear
Journal Article2012-05-21No SnippetsSana J, Faltejskova P, Svoboda M, Slaby O.
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For the many years, the central dogma of molecular biology has been that RNA functions mainly as an informational intermediate between a DNA sequence and its encoded protein. But one of the great surprises of modern biology was the discovery that protein-coding genes represent less than 2% of the total genome sequence, and subsequently the fact that at least 90% of the human genome is actively transcribed. Thus, the human transcriptome was found to be more complex than a collection of protein-coding genes and their splice variants. Although initially argued to be spurious transcriptional noise or accumulated evolutionary debris arising from the early assembly of genes and/or the insertion of mobile genetic elements, recent evidence suggests that the non-coding RNAs (ncRNAs) may play major biological roles in cellular development, physiology and pathologies. NcRNAs could be grouped into two major classes based on the transcript size; small ncRNAs and long ncRNAs. Each of these classes can be further divided, whereas novel subclasses are still being discovered and characterized. Although, in the last years, small ncRNAs called microRNAs were studied most frequently with more than ten thousand hits at PubMed database, recently, evidence has begun to accumulate describing the molecular mechanisms by which a wide range of novel RNA species function, providing insight into their functional roles in cellular biology and in human disease. In this review, we summarize newly discovered classes of ncRNAs, and highlight their functioning in cancer biology and potential usage as biomarkers or therapeutic targets.
Journal Article2012-05-21No SnippetsSavariz FC, Foglio MA, de Carvalho JE, Ruiz AL, Duarte MC, da Rosa MF, Meyer E, Sarragiotto MH.
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In the present work, we report the synthesis and in vitro anticancer and antimicrobial activity evaluation of a new series of 1-substituted-β-carboline derivatives bearing a 4-benzylidene-4H-oxazol-5-one unity at C-3. The compound 2-[1-(4-methoxyphenyl)-9H-β-carbolin-3-yl]-4-(benzylidene)-4H-oxazol-5-one (11) was the most active derivative, exhibiting a potent cytotoxic activity against glioma (U251), prostate (PC-3) and ovarian (OVCAR-03) cancer cell lines with IC50 values of 0.48, 1.50 and 1.07 µM, respectively. An in silico study of the ADME properties of the novel synthesized β-carboline derivatives was also performed.
Low-molecular weight heparin (LMWH) is widely used in anticoagulation therapies and for the prevention of thrombosis. LMWH is administered by subcutaneous injection usually once or twice per day. This frequent and invasive delivery modality leads to compliance issues for individuals on prolonged therapeutic courses, particularly pediatric patients. Here, we report a long-term delivery method for LMWH via subcutaneous injection of long-lasting hydrogels. LMWH is modified with reactive maleimide groups so that it can be crosslinked into continuous networks with four-arm thiolated poly(ethylene glycol) (PEG-SH). Maleimide-modified LMWH (Mal-LMWH) retains bioactivity as indicated by prolonged coagulation time. Hydrogels comprising PEG-SH and Mal-LMWH degrade via hydrolysis, releasing bioactive LMWH by first-order kinetics with little initial burst release. Separately dissolved Mal-LMWH and PEG-SH solutions were co-injected subcutaneously in New Zealand White rabbits. The injected solutions successfully formed hydrogels in situ and released LMWH as measured via chromogenic assays on plasma samples, with accumulation of LMWH occurring at day 2 and rising to near-therapeutic dose equivalency by day 5. These results demonstrate the feasibility of using LMWH-containing, crosslinked hydrogels for sustained and controlled release of anticoagulants.
Also flagged:gene expressiondegradationtranslationalneurogenesisneural stem cell proliferationdifferentiation
Journal Article2012-05-21✓ 1 SnippetLang MF, Shi Y.
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Introduction)
…3 homeobox 2 (POU3F2or BRN2), to…
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MicroRNAs (miRNAs) are short non-coding RNAs that regulate gene expression at the post-transcriptional level by mediating mRNA degradation or translational inhibition. MiRNAs are implicated in many biological functions, including neurogenesis. It has been shown that miRNAs regulate multiple steps of neurogenesis, from neural stem cell proliferation to neuronal differentiation and maturation. MiRNAs execute their functions in a dynamic and context-dependent manner by targeting diverse downstream target genes, from transcriptional factors to epigenetic regulators. Identifying context-specific target genes is instrumental for understanding the roles that miRNAs play in neurogenesis. This review summarizes our current state of knowledge on the dynamic roles that miRNAs play in neural stem cells and neurogenesis.
Also flagged:autosomeschromosomeschromosomeLEPRMTTPFABP5
Journal Article2012-05-20No SnippetsFernández AI, Pérez-Montarelo D, Barragán C, Ramayo-Caldas Y, Ibáñez-Escriche N, Castelló A, Noguera JL, Silió L, Folch JM, Rodríguez MC.
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<h4>Background</h4>The traditional strategy to map QTL is to use linkage analysis employing a limited number of markers. These analyses report wide QTL confidence intervals, making very difficult to identify the gene and polymorphisms underlying the QTL effects. The arrival of genome-wide panels of SNPs makes available thousands of markers increasing the information content and therefore the likelihood of detecting and fine mapping QTL regions. The aims of the current study are to confirm previous QTL regions for growth and body composition traits in different generations of an Iberian x Landrace intercross (IBMAP) and especially identify new ones with narrow confidence intervals by employing the PorcineSNP60 BeadChip in linkage analyses.<h4>Results</h4>Three generations (F3, Backcross 1 and Backcross 2) of the IBMAP and their related animals were genotyped with PorcineSNP60 BeadChip. A total of 8,417 SNPs equidistantly distributed across autosomes were selected after filtering by quality, position and frequency to perform the QTL scan. The joint and separate analyses of the different IBMAP generations allowed confirming QTL regions previously identified in chromosomes 4 and 6 as well as new ones mainly for backfat thickness in chromosomes 4, 5, 11, 14 and 17 and shoulder weight in chromosomes 1, 2, 9 and 13; and many other to the chromosome-wide signification level. In addition, most of the detected QTLs displayed narrow confidence intervals, making easier the selection of positional candidate genes.<h4>Conclusions</h4>The use of higher density of markers has allowed to confirm results obtained in previous QTL scans carried out with microsatellites. Moreover several new QTL regions have been now identified in regions probably not covered by markers in previous scans, most of these QTLs displayed narrow confidence intervals. Finally, prominent putative biological and positional candidate genes underlying those QTL effects are listed based on recent porcine genome annotation.
Also flagged:Osteosarcomacancertumourosteosarcomaschromosomesoncogenes
Journal Article2012-05-20No SnippetsMartin JW, Squire JA, Zielenska M.
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Osteosarcoma is a primary bone malignancy with a particularly high incidence rate in children and adolescents relative to other age groups. The etiology of this often aggressive cancer is currently unknown, because complicated structural and numeric genomic rearrangements in cancer cells preclude understanding of tumour development. In addition, few consistent genetic changes that may indicate effective molecular therapeutic targets have been reported. However, high-resolution techniques continue to improve knowledge of distinct areas of the genome that are more commonly associated with osteosarcomas. Copy number gains at chromosomes 1p, 1q, 6p, 8q, and 17p as well as copy number losses at chromosomes 3q, 6q, 9, 10, 13, 17p, and 18q have been detected by numerous groups, but definitive oncogenes or tumour suppressor genes remain elusive with respect to many loci. In this paper, we examine studies of the genetics of osteosarcoma to comprehensively describe the heterogeneity and complexity of this cancer.
Journal Article2012-05-19✓ 3 SnippetsKubben N, Adriaens M, Meuleman W, Voncken JW, van Steensel B, Misteli T.
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I A O 0000326)
…Olfm4…
I A O 0000326)
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…Rabgap1l…
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Mutations in the A-type lamins A and C, two major components of the nuclear lamina, cause a large group of phenotypically diverse diseases collectively referred to as laminopathies. These conditions often involve defects in chromatin organization. However, it is unclear whether A-type lamins interact with chromatin in vivo and whether aberrant chromatin-lamin interactions contribute to disease. Here, we have used an unbiased approach to comparatively map genome-wide interactions of gene promoters with lamin A and progerin, the mutated lamin A isoform responsible for the premature aging disorder Hutchinson-Gilford progeria syndrome (HGPS) in mouse cardiac myoytes and embryonic fibroblasts. We find that lamin A-associated genes are predominantly transcriptionally silent and that loss of lamin association leads to the relocation of peripherally localized genes, but not necessarily to their activation. We demonstrate that progerin induces global changes in chromatin organization by enhancing interactions with a specific subset of genes in addition to the identified lamin A-associated genes. These observations demonstrate disease-related changes in higher order genome organization in HGPS and provide novel insights into the role of lamin-chromatin interactions in chromatin organization.
Also flagged:DNA polymerasemorpholinesynthesisDNA polymerasesDeoxynucleosidetriphosphate
Journal Article2012-05-18No SnippetsWu Y, Zakharova VM, Kashemirov BA, Goodman MF, Batra VK, Wilson SH, McKenna CE.
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Deoxynucleoside 5'-triphosphate analogues in which the β,γ-bridging oxygen has been replaced with a CXY group are useful chemical probes to investigate DNA polymerase catalytic and base-selection mechanisms. A limitation of such probes has been that conventional synthetic methods generate a mixture of diastereomers when the bridging carbon substitution is nonequivalent (X ≠ Y). We report here a general solution to this long-standing problem with four examples of β,γ-CXY dNTP diastereomers: (S)- and (R)-β,γ-CHCl-dGTP (12a-1/12a-2) and (S)- and (R)-β,γ-CHF-dGTP (12b-1/12b-2). Central to their preparation was conversion of the prochiral parent bisphosphonic acids to the P,C-dimorpholinamide derivatives 7 of their (R)-mandelic acid monoesters, which provided access to the individual diastereomers 7a-1, 7a-2, 7b-1, and 7b-2 by preparative HPLC. Selective acidic hydrolysis of the P-N bond then afforded "portal" diastereomers, which were readily coupled to morpholine-activated dGMP. Removal of the chiral auxiliary by H(2) (Pd/C) gave the four individual diastereomeric nucleotides 12, which were characterized by (31)P, (1)H, and (19)F NMR spectroscopy and by mass spectrometry. After treatment with Chelex-100 to remove traces of paramagnetic ions, at pH ~10 the diastereomer pairs 12a,b exhibit discrete P(α) and P(β)(31)P resonances. The more upfield P(α) and more downfield P(β) resonances (and also the more upfield (19)F NMR resonance in 12b) are assigned to the R configuration at the P(β)-CHX-P(γ) carbons on the basis of the absolute configurations of the individual diastereomers as determined from the X-ray crystallographic structures of their ternary complexes with DNA and polymerase β.
Also flagged:phenylalanineExtracellularbiomineralizationhydroxyapatiteamino acidfluorine
Journal Article2012-05-18No SnippetsWeidner T, Dubey M, Breen NF, Ash J, Baio JE, Jaye C, Fischer DA, Drobny GP, Castner DG.
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Extracellular biomineralization proteins such as salivary statherin control the growth of hydroxyapatite (HAP), the principal component of teeth and bones. Despite the important role that statherin plays in the regulation of hard tissue formation in humans, the surface recognition mechanisms involved are poorly understood. The protein-surface interaction likely involves very specific contacts between the surface atoms and the key protein side chains. This study demonstrates for the first time the power of combining near-edge X-ray absorption fine structure (NEXAFS) spectroscopy with element labeling to quantify the orientation of individual side chains. In this work, the 15 amino acid N-terminal binding domain of statherin has been adsorbed onto HAP surfaces, and the orientations of phenylalanine rings F7 and F14 have been determined using NEXAFS analysis and fluorine labels at individual phenylalanine sites. The NEXAFS-derived phenylalanine tilt angles have been verified with sum frequency generation spectroscopy.
Also flagged:Raf kinasenasopharyngeal carcinomaRaf kinase inhibitory proteinRKIPcancerpolymerase
Journal Article2012-05-18✓ 1 SnippetLi SW, Wang H, Xiang YQ, Zhang HB, Lv X, Xia WX, Zeng MS, Mai HQ, Hong MH, Guo X.
In-Text Gene Mentions
Title)
…Prospective study of prognostic value of Raf kinase inhibitory protein and pretreatment plasma Epstein-Barr virus DNA for distant metastasis in locoregionally advanced nasopharyngeal carcinoma.…
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<h4>Background</h4>The purpose of this prospective study was to investigate the predictive significance of Raf kinase inhibitory protein (RKIP) in locoregionally advanced nasopharyngeal carcinoma (NPC) and its effect on distant metastasis.<h4>Methods</h4>The usual immunohistochemical stainings were performed to detect RKIP expression of cancer tissues from 210 patients with advanced NPC. After DNA samples from pretreatment plasma from these patients were extracted, real-time polymerase chain reaction (PCR) was performed to quantitatively analyze plasma Epstein-Barr virus (EBV) DNA.<h4>Results</h4>RKIP expression was significantly different for different N classifications and WHO pathologic grades, respectively (p < .05). Cox regression confirmed RKIP and EBV DNA were independent prognostic markers for 5-year distant metastasis-free survival (DMFS). In the high RKIP expression group, chemotherapy had a positive effect on improved DMFS, but not in the low RKIP expression group.<h4>Conclusions</h4>RKIP could be identified as an independent prognostic factor on DMFS. For each combined treatment modality, the different impact of chemotherapy on distant metastasis might be related to the RKIP expression level.
Also flagged:estrogenPDGFAblestrogen receptorERbinding
Journal Article2012-05-18✓ 2 SnippetsWeigel MT, Ghazoui Z, Dunbier A, Pancholi S, Dowsett M, Martin LA.
In-Text Gene Mentions
S I O 001029)
…Abl, Abelson tyrosine kinase; AIB1, amplified in breast cancer 1; CBP, CREB binding protein; ChIP, chromatin immunoprecipitation; DCC, dextran charcoal-stripped bovine serum; E2, estradiol; ER, estrogen receptor; ERE, estrogen response element; LTED, long term estrogen deprived; SEM, standard error of the mean; wt, wild type.…
I A O 0000606)
…Abl: Abelson tyrosine kinase; AI: aromatase inhibitor; AIB1: amplified in breast cancer 1; CBP: CREB binding protein; ChIP: chromatin immunoprecipitation; DCC: dextran charcoal-stripped bovine serum; E2: estradiol; ERBB2: human epidermal growth factor receptor 2; ER: estrogen receptor; ERE: estrogen response element; GREB1: gene regulated by estrogen in breast cancer 1; IFN: interferon; IGF1: insulin like growth factor; LTED: long term estrogen deprived; MG: metagene; PBS: phosphate buffered saline; PDGFR: platelet derived growth factor receptor; PI3K: phosphatidylinositol 3-kinases; RT-PCR: reverse transcriptase polymerase chain reaction; s.e.m.: standard error of the mean; siRNA: small interfering RNA; STAT: signal transducer and activator of transcription; wt: wild type.…
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<h4>Introduction</h4>The majority of breast tumors at primary diagnosis are estrogen receptor positive (ER+). Estrogen (E) mediates its effects by binding to the ER. Therapies targeting the estrogenic stimulation of tumor growth reduce mortality from ER+ breast cancer. However, resistance remains a major clinical problem.<h4>Methods</h4>To identify molecular mechanisms associated with resistance to E-deprivation, we assessed the temporal changes in global gene expression during adaptation to long-term culture of MCF7 human breast cancer cells in the absence of estradiol (E2), long term estrogen deprived (LTED), that leads to recovery of proliferative status and models resistance to an aromatase inhibitor (AI). The expression levels of proteins were determined by western blotting. Proliferation assays were carried out using the dual platelet derived growth factor receptor (PDGFR)/Abelson tyrosine kinase (Abl) inhibitor nilotinib. Luciferase reporter assays were used to determine effects on ER-mediated transactivation. Changes in recruitment of cofactors to the gene regulated by estrogen in breast cancer 1 (GREB1) promoter were determined by chromatin immunoprecipitation (ChIP). Gene expression data were derived from 81 postmenopausal women with ER+ BC pre-treatment and at two-weeks post-treatment with single agent anastrozole in a neoadjuvant trial.<h4>Results</h4>The PDGF/Abl canonical pathway was significantly elevated as early as one week post E-deprivation (P = 1.94 E-04) and this became the top adaptive pathway at the point of proliferative recovery (P = 1.15 E-07). Both PDGFRβ and Abl protein levels were elevated in the LTED cells compared to wild type (wt)-MCF7 cells. The PDGF/Abl tyrosine kinase inhibitor nilotinib, suppressed proliferation in LTED cells in the presence or absence of E. Nilotinib also suppressed ER-mediated transcription by destabilizing the ER and reducing recruitment of amplified in breast cancer-1 (AIB1) and the CREB binding protein (CBP) to the promoter of the E-responsive gene GREB1. High PDGFRβ in primary ER+ breast cancer of 81 patients prior to neoadjuvant treatment with an AI was associated with poorer antiproliferative response. Additionally PDGFRβ expression increased after two weeks of AI therapy (1.25 fold, P = 0.003).<h4>Conclusions</h4>These preclinical and clinical data indicate that the PDGF/Abl signaling pathway merits clinical evaluation as a therapeutic target with endocrine therapy in ER+ breast cancer.
Also flagged:Mitochondriamitochondrialbrain ischemiaskeletal muscle myopathiesneurodegenerative diseasesneurological disorders
Journal Article2012-05-18✓ 4 SnippetsCalì T, Ottolini D, Brini M.
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S I O 001029)
…However, whether the Htt fragment aggregates play a role in HD pathogenesis, and whether the oligomers (and/or aggregates) are toxic or protective, is still debated [133,134].…
S I O 001029)
…Fig. 4 summarizes the main pathways that have been proposed, and a succinct overview of the data present in the literature will be presented here. As it was found in other neurodegenerative diseases, mitochondria isolated from lymphoblast of HD patients and from the brain of HD mice models have impaired ability to take up Ca2+. They are more susceptible to Ca2+ overload, with the vulnerability proportional to the length of the mutant Htt poly-Q expansion [135,136]. The matrix Ca2+ overload favors mPTP opening, which has been shown to be prevented by CsA in studies on mitochondria isolated from striatal neurons expressing mutant Htt [137] and from muscle of HD model R6/2 mice [138]. These findings have been confirmed also in cultured cells, e.g., the expression of mutant Htt in mouse immortalized striatal cells made mitochondria unable to handle large Ca2+ loads, very likely because of induced mPTP opening. The observed decrease of mitochondrial Ca2+, appears to be a compensatory attempt to prevent the mitochondrial Ca2+ stress that would irreversibly damage the organelles and eventually lead to cell death [69]. However, the ablation of cyclophilin D in HD mouse models failed to induce any improvement in the disease progression, despite the increased Ca2+-buffering capacity of their mitochondria [139–141]. These controversial findings are possibly related to the different experimental conditions, but also to the loss of the contribution of the ER compartment in experiments performed in isolated mitochondria. In fact, a number of reports have described the involvement of ER Ca2+ handling in HD cellular models. Htt was shown to influence intracellular Ca2+ signaling by acting on the InsP3R activity and expression [69,142–144], and striatal precursors of HD neurons display increased Ca2+ content in the ER [145] that could compromise mitochondria Ca2+ handling. Another aspect of mitochondria in other neurodegenerative diseases is shared by HD: the mitochondrial fission/fusion balance is affected by the presence of mutant Htt in different HD models, possibly as a consequence of the enhanced calcineurin activity, and thus of the calcineurin-dependent Drp1 recruitment to mitochondria. The enhanced mitochondria fragmentation led to enhanced apoptotic sensitivity, thus accounting for an early role of Ca2+ dysregulation in the death of striatal neurons [145].…
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…The mutant forms of Htt contain more than 35 repeats and there is a direct correlation between the number of glutamines over 35 and the severity of the disease.…
S I O 001029)
…The genetic cause is the abnormal expansion of CAG repeats (corresponding to a poly-glutamine stretch (poly-Q)) in exon 1 of the gene coding for Huntingtin protein (Htt).…
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Mitochondria are essential for ensuring numerous fundamental physiological processes such as cellular energy, redox balance, modulation of Ca(2+) signaling and important biosynthetic pathways. They also govern the cell fate by participating in the apoptosis pathway. The mitochondrial shape, volume, number and distribution within the cells are strictly controlled. The regulation of these parameters has an impact on mitochondrial function, especially in the central nervous system, where trafficking of mitochondria is critical to their strategic intracellular distribution, presumably according to local energy demands. Thus, the maintenance of a healthy mitochondrial population is essential to avoid the impairment of the processes they regulate: for this purpose, cells have developed mechanisms involving a complex system of quality control to remove damaged mitochondria, or to renew them. Defects of these processes impair mitochondrial function and lead to disordered cell function, i.e., to a disease condition. Given the standard role of mitochondria in all cells, it might be expected that their dysfunction would give rise to similar defects in all tissues. However, damaged mitochondrial function has pleiotropic effects in multicellular organisms, resulting in diverse pathological conditions, ranging from cardiac and brain ischemia, to skeletal muscle myopathies to neurodegenerative diseases. In this review, we will focus on the relationship between mitochondrial (and cellular) derangements and Ca(2+) dysregulation in neurodegenerative diseases, emphasizing the evidence obtained in genetic models. Common patterns, that recognize the derangement of Ca(2+) and energy control as a causative factor, have been identified: advances in the understanding of the molecular regulation of Ca(2+) homeostasis, and on the ways in which it could become perturbed in neurological disorders, may lead to the development of therapeutic strategies that modulate neuronal Ca(2+) signaling.
Also flagged:G-protein-coupled receptorsneurogenesisGPCRsnorepinephrinedopamineserotonin
Journal Article2012-05-18✓ 1 SnippetDoze VA, Perez DM.
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…HTT…
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The importance of adult neurogenesis has only recently been accepted, resulting in a completely new field of investigation within stem cell biology. The regulation and functional significance of adult neurogenesis is currently an area of highly active research. G-protein-coupled receptors (GPCRs) have emerged as potential modulators of adult neurogenesis. GPCRs represent a class of proteins with significant clinical importance, because approximately 30% of all modern therapeutic treatments target these receptors. GPCRs bind to a large class of neurotransmitters and neuromodulators such as norepinephrine, dopamine, and serotonin. Besides their typical role in cellular communication, GPCRs are expressed on adult neural stem cells and their progenitors that relay specific signals to regulate the neurogenic process. This review summarizes the field of adult neurogenesis and its methods and specifies the roles of various GPCRs and their signal transduction pathways that are involved in the regulation of adult neural stem cells and their progenitors. Current evidence supporting adult neurogenesis as a model for self-repair in neuropathologic conditions, adult neural stem cell therapeutic strategies, and potential avenues for GPCR-based therapeutics are also discussed.
Also flagged:lipiddiabetic dyslipidemiacoronary artery diseaseBUD13ZNF259CETP
Journal Article2012-05-18✓ 1 SnippetBraun TR, Been LF, Singhal A, Worsham J, Ralhan S, Wander GS, Chambers JC, Kooner JS, Aston CE, Sanghera DK.
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Methods)
…diabetes (from e.g.hemochromatosis, pancreatitis) were excluded…
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Recent genome-wide association scans (GWAS) and meta-analysis studies on European populations have identified many genes previously implicated in lipid regulation. Validation of these loci on different global populations is important in determining their clinical relevance, particularly for development of novel drug targets for treating and preventing diabetic dyslipidemia and coronary artery disease (CAD). In an attempt to replicate GWAS findings on a non-European sample, we examined the role of six of these loci (CELSR2-PSRC1-SORT1 rs599839; CDKN2A-2B rs1333049; BUD13-ZNF259 rs964184; ZNF259 rs12286037; CETP rs3764261; APOE-C1-C4-C2 rs4420638) in our Asian Indian cohort from the Sikh Diabetes Study (SDS) comprising 3,781 individuals (2,902 from Punjab and 879 from the US). Two of the six SNPs examined showed convincing replication in these populations of Asian Indian origin. Our study confirmed a strong association of CETP rs3764261 with high-density lipoprotein cholesterol (HDL-C) (p = 2.03×10(-26)). Our results also showed significant associations of two GWAS SNPs (rs964184 and rs12286037) from BUD13-ZNF259 near the APOA5-A4-C3-A1 genes with triglyceride (TG) levels in this Asian Indian cohort (rs964184: p = 1.74×10(-17); rs12286037: p = 1.58×10(-2)). We further explored 45 SNPs in a ∼195 kb region within the chromosomal region 11q23.3 (encompassing the BUD13-ZNF259, APOA5-A4-C3-A1, and SIK3 genes) in 8,530 Asian Indians from the London Life Sciences Population (LOLIPOP) (UK) and SDS cohorts. Five more SNPs revealed significant associations with TG in both cohorts individually as well as in a joint meta-analysis. However, the strongest signal for TG remained with BUD13-ZNF259 (rs964184: p = 1.06×10(-39)). Future targeted deep sequencing and functional studies should enhance our understanding of the clinical relevance of these genes in dyslipidemia and hypertriglyceridemia (HTG) and, consequently, diabetes and CAD.
Also flagged:ironiron deficiencyHampHjvErythropoietinEPO
Journal Article2012-05-18✓ 5 SnippetsKrijt J, Frýdlová J, Kukačková L, Fujikura Y, Přikryl P, Vokurka M, Nečas E.
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Introduction)
…A less severe form of hemochromatosis, associated with a less dramatic decrease in hepcidin expression, is caused by disrupted synthesis of two other membrane proteins: transferrin receptor 2 (Tfr2) [13] and the Hfe protein [14].…
Introduction)
…results in severehemochromatosis, which is in…
Introduction)
…overload similar tohemochromatosiscaused by disruption…
Introduction)
…severe form ofhemochromatosis, associated with a…
Introduction)
…[13] and theHfeprotein [14] .…
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<h4>Introduction</h4>Hemojuvelin (Hjv) is a key component of the signaling cascade that regulates liver hepcidin (Hamp) expression. The purpose of this study was to determine Hjv protein levels in mice and rats subjected to iron overload and iron deficiency.<h4>Methods</h4>C57BL/6 mice were injected with iron (200 mg/kg); iron deficiency was induced by feeding of an iron-deficient diet, or by repeated phlebotomies. Erythropoietin (EPO)-treated mice were administered recombinant EPO at 50 U/mouse. Wistar rats were injected with iron (1200 mg/kg), or fed an iron-deficient diet. Hjv protein was determined by immunoblotting, liver samples from Hjv-/- mice were used as negative controls. Mouse plasma Hjv content was determined by a commercial ELISA kit.<h4>Results</h4>Liver crude membrane fraction from both mice and rats displayed a major Hjv-specific band at 35 kDa, and a weaker band of 20 kDa. In mice, the intensity of these bands was not changed following iron injection, repeated bleeding, low iron diet or EPO administration. No change in liver crude membrane Hjv protein was observed in iron-treated or iron-deficient rats. ELISA assay for mouse plasma Hjv did not show significant difference between Hjv+/+ and Hjv-/- mice. Liver Hamp mRNA, Bmp6 mRNA and Id1 mRNA displayed the expected response to iron overload and iron deficiency. EPO treatment decreased Id1 mRNA, suggesting possible participation of the bone morphogenetic protein pathway in EPO-mediated downregulation of Hamp mRNA.<h4>Discussion</h4>Since no differences between Hjv protein levels were found following various experimental manipulations of body iron status, the results indicate that, in vivo, substantial changes in Hamp mRNA can occur without noticeable changes of membrane hemojuvelin content. Therefore, modulation of hemojuvelin protein content apparently does not represent the limiting step in the control of Hamp gene expression.
The antimicrobial agents triclosan (TCS), triclocarban (TCC) and their associated transformation products are of increasing concern as environmental pollutants due to their potential adverse effects on humans and wildlife, including bioaccumulation and endocrine-disrupting activity. Analysis by tandem mass spectrometry of 24 paired freshwater bed sediment samples (top 10 cm) collected by the U.S. Geological Survey near 12 wastewater treatment plants (WWTPs) in Minnesota revealed TCS and TCC concentrations of up to 85 and 822 ng/g dry weight (dw), respectively. Concentrations of TCS and TCC in bed sediments collected downstream of WWTPs were significantly greater than upstream concentrations in 58% and 42% of the sites, respectively. Dichloro- and non-chlorinated carbanilides (DCC and NCC) were detected in sediments collected at all sites at concentrations of up to 160 and 1.1 ng/g dw, respectively. Overall, antimicrobial concentrations were significantly higher in lakes than in rivers and creeks, with relative abundances decreasing from TCC>TCS>DCC>NCC. This is the first statewide report on the occurrence of TCS, TCC and TCC transformation products in freshwater sediments. Moreover, the results suggest biological or chemical TCC dechlorination products to be ubiquitous in freshwater environments of Minnesota, but whether this transformation occurs in the WWTP or bed sediment remains to be determined.
Also flagged:schizophreniacognitionSLC6A4serotonin transporterserotonin5-hydroxytryptamin
Journal Article2012-05-17✓ 4 SnippetsLindholm Carlström E, Saetre P, Rosengren A, Thygesen JH, Djurovic S, Melle I, Andreassen OA, Werge T, Agartz I, Hall H, Terenius L, Jönsson EG.
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…Multiple lines of evidence suggest that genetic variation in the serotonin transporter gene (SLC6A4; 5-HTT) is associated with schizophrenia and suicidal behavior.…
Abstract)
…( SLC6A4 ;5-HTT) is associated…
Introduction)
…( SLC6A4 or5-HTT) [ 11…
Introduction)
…from studies of5-HTTknockout mouse have…
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<h4>Background</h4>The serotonin (5-hydroxytryptamin; 5-HT) system has a central role in the circuitry of cognition and emotions. Multiple lines of evidence suggest that genetic variation in the serotonin transporter gene (SLC6A4; 5-HTT) is associated with schizophrenia and suicidal behavior. In this study, we wanted to elucidate whether SLC6A4 variations is involved in attempted suicide among patients with schizophrenia in a Scandinavian case-control sample.<h4>Methods</h4>Patients diagnosed with schizophrenia from three Scandinavian samples were assessed for presence or absence of suicide attempts, based on record reviews and interview data. Seven SLC6A4 single nucleotide polymorphisms (SNPs) were genotyped in 837 schizophrenia patients and 1,473 control individuals. Association analyses and statistical evaluations were performed with the program UNPHASED (version 3.0.9).<h4>Results</h4>We observed an allele association between the SNP rs16965628, located in intron one of SLC6A4, and attempted suicide (adjusted p-value 0.01), among patients with schizophrenia. No association was found to a diagnosis of schizophrenia, when patients were compared to healthy control individuals.<h4>Conclusion</h4>The gene SLC6A4 appears to be involved in suicidal ideation among patients with schizophrenia. Independent replication is needed before more firm conclusions can be drawn.
Also flagged:Filamin Amatrix metalloproteinaseactin-binding proteinscell surface adhesion proteinscytoskeletoncell motility
Journal Article2012-05-17✓ 1 SnippetBaldassarre M, Razinia Z, Brahme NN, Buccione R, Calderwood DA.
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Filamins are an important family of actin-binding proteins that, in addition to bundling actin filaments, link cell surface adhesion proteins, signaling receptors and channels to the actin cytoskeleton, and serve as scaffolds for an array of intracellular signaling proteins. Filamins are known to regulate the actin cytoskeleton, act as mechanosensors that modulate tissue responses to matrix density, control cell motility and inhibit activation of integrin adhesion receptors. In this study, we extend the repertoire of filamin activities to include control of extracellular matrix (ECM) degradation. We show that knockdown of filamin increases matrix metalloproteinase (MMP) activity and induces MMP2 activation, enhancing the ability of cells to remodel the ECM and increasing their invasive potential, without significantly altering two-dimensional random cell migration. We further show that within filamin A, the actin-binding domain is necessary, but not sufficient, to suppress the ECM degradation seen in filamin-A-knockdown cells and that dimerization and integrin binding are not required. Filamin mutations are associated with neuronal migration disorders and a range of congenital malformations characterized by skeletal dysplasia and various combinations of cardiac, craniofacial and intestinal anomalies. Furthermore, in breast cancers loss of filamin A has been correlated with increased metastatic potential. Our data suggest that effects on ECM remodeling and cell invasion should be considered when attempting to provide cellular explanations for the physiological and pathological effects of altered filamin expression or filamin mutations.
Also flagged:peptidethioleneethylene glycolα-smooth muscleP15
Journal Article2012-05-17No SnippetsGould ST, Darling NJ, Anseth KS.
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A thiol-ene polymerization platform was used to synthesize peptide functionalized poly(ethylene glycol) hydrogels, which were initially characterized and compared to theoretical predictions of Young's modulus via a theoretical crosslinking density equation presented herein. After thorough characterization, this material system's utility for answering specific biological hypotheses was demonstrated with the culture and observation of aortic valvular interstitial cells (VICs). Specifically, these materials were used to better understand the role of substrate elasticity and biochemical functionality on VIC α-smooth muscle (αSMA) expression and secretory properties (i.e. de novo extracellular matrix (ECM)). The Young's moduli of the hydrogels varied from 28kPa (activating, 90% myofibroblasts) to 4kPa (non-activating, 15% myofibroblast), and the biochemical functionality was tailored by incorporating three small adhesive peptide sequences, RGDS, VGVAPG and P15. To promote VIC adhesion, a basal [RGDS] of 0.8mM was used in all formulations, while the [VGVAPG] or [P15] were varied to be lower than, equal to or higher than 0.8mM. The substrates with 1.2mM VGVAPG and all gels with P15 led to significantly higher αSMA expression for both stiff and soft substrates, as compared to 0.8mM RGDS alone. Importantly, all gel conditions αSMA expression were significantly lower than tissue culture poly(styrene) (TCPS; ∼4- to 10-fold difference). The ECM produced decreased significantly as the total integrin-binding peptide concentration increased, but was significantly higher than that produced on TCPS. This easily tailored material system provides a useful culture platform to improve the fundamental understanding of VIC biology through isolating specific biological cues and observing VIC function.
Cellular iron homeostasis is maintained by iron regulatory proteins 1 and 2 (IRP1 and IRP2). IRPs bind to iron-responsive elements (IREs) located in the untranslated regions of mRNAs encoding protein involved in iron uptake, storage, utilization and export. Over the past decade, significant progress has been made in understanding how IRPs are regulated by iron-dependent and iron-independent mechanisms and the pathological consequences of IRP2 deficiency in mice. The identification of novel IREs involved in diverse cellular pathways has revealed that the IRP-IRE network extends to processes other than iron homeostasis. A mechanistic understanding of IRP regulation will likely yield important insights into the basis of disorders of iron metabolism. This article is part of a Special Issue entitled: Cell Biology of Metals.
Also flagged:Raf kinase inhibitor proteinRKIPRaf1G protein-coupled receptor kinasekinase(GRK) 2
Journal Article2012-05-17No SnippetsDeiss K, Kisker C, Lohse MJ, Lorenz K.
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Proteins controlling cellular networks have evolved distinct mechanisms to ensure specificity in protein-protein interactions. Raf kinase inhibitor protein (RKIP) is a multifaceted kinase modulator, but it is not well understood how this small protein (21 kDa) can coordinate its diverse signaling functions. Raf1 and G protein-coupled receptor kinase (GRK) 2 are direct interaction partners of RKIP and thus provide the possibility to untangle the mechanism of its target specificity. Here, we identify RKIP dimer formation as an important mechanistic feature in the target switch from Raf1 to GRK2. Co-immunoprecipitation and cross-linking experiments revealed RKIP dimerization upon phosphorylation of RKIP at serine 153 utilizing purified proteins as well as in cells overexpressing RKIP. A functional phosphomimetic RKIP mutant had a high propensity for dimerization and reproduced the switch from Raf1 to GRK2. RKIP dimerization and GRK2 binding, but not Raf1 interaction, were prevented by a peptide comprising amino acids 127-146 of RKIP, which suggests that this region is critical for dimer formation. Furthermore, a dimeric RKIP mutant displayed a higher affinity to GRK2, but a lower affinity to Raf1. Functional analyses of phosphomimetic as well as dimeric RKIP demonstrated that enhanced dimerization of RKIP translates into decreased Raf1 and increased GRK2 inhibition. The detection of RKIP dimers in a complex with GRK2 in murine hearts implies their physiological relevance. These findings represent a novel mechanistic feature how RKIP can discriminate between its different interaction partners and thus advances our understanding how specific inhibition of kinases can be achieved.
<h4>Objective</h4>Since tumor radiation response is oxygen-dependent, radiosensitivity can be enhanced by increasing tumor oxygenation. Theoretically, inhibiting cellular oxygen consumption is the most efficient way to increase oxygen levels. The cationic, rhodacyanine dye-analog MKT-077 inhibits mitochondrial respiration and could be an effective metabolic inhibitor. However, the relationship between cellular MKT-077 uptake and metabolic inhibition is unknown. We hypothesized that rat and human mammary carcinoma cells would take up MKT-077, causing a decrease in oxygen metabolism related to drug uptake.<h4>Methods</h4>R3230Ac rat breast adenocarcinoma cells were exposed to MKT-077. Cellular MKT-077 concentration was quantified using spectroscopy, and oxygen consumption was measured using polarographic electrodes. MKT-077 uptake kinetics were modeled by accounting for uptake due to both the concentration and potential gradients across the plasma and mitochondrial membranes. These kinetic parameters were used to model the relationship between MKT-077 uptake and metabolic inhibition. MKT-077-induced changes in oxygen consumption were also characterized in MDA-MB231 human breast carcinoma cells.<h4>Results</h4>Cells took up MKT-077 with a time constant of ∼1 hr, and modeling showed that over 90% of intracellular MKT-077 was bound or sequestered, likely by the mitochondria. The uptake resulted in a rapid decrease in oxygen consumption, with a time constant of ∼30 minutes. Surprisingly the change in oxygen consumption was proportional to uptake rate, not cellular concentration. MKT-077 proved a potent metabolic inhibitor, with dose-dependent decreases of 45-73% (p = 0.003).<h4>Conclusions</h4>MKT-077 caused an uptake rate-dependent decrease in cellular metabolism, suggesting potential efficacy for increasing tumor oxygen levels and radiosensitivity in vivo.
Journal Article2012-05-17✓ 1 SnippetGeorgakopoulou EA, Achtari MD, Achtaris M, Foukas PG, Kotsinas A.
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S I O 001029)
…Recently, the role of the neuronal axon guidance molecule netrin-1 and its receptors (DCC, UNC5H) have been discovered to play a pivotal role in progression of IBD to colon adenocarcinoma, [98, 99] and its expression is probably upregulated through NF-kappaB [100].…
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Oral lichen planus (OLP) is a chronic oral inflammatory disease of unknown etiology. According to reports, 1-2% of OLP patients develop oral squamous cell carcinoma (OSCC) in the long run. While World Health Organization (WHO) classifies OLP as "a potentially malignant disorder," it is still a matter of debate which mechanisms drive OLP to such a condition. The current hypothesis connecting OLP and OSCC is that chronic inflammation results in crucial DNA damage which over time results in cancer development. Initial studies investigating the OLP and OSCC link were mainly retrospective clinical studies. Over the past years, several amount of information has accumulated, mainly from molecular studies on the OLP malignant potential. This article is a critical review of whether OLP has a malignant potential and, therefore, represents a model of preneoplastic inflammation.
Also flagged:serine proteaseproteaseSchistosomiasisparasitic infectionstegumentportal hypertension
Journal Article2012-05-17✓ 1 SnippetGranzin J, Huang Y, Topbas C, Huang W, Wu Z, Misra S, Hazen SL, Blanton RE, Lee X, Weiergräber OH.
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Parasitic organisms are constantly challenged by the defence mechanisms of their respective hosts, which often depend on serine protease activities. Consequently, protease inhibitors such as those belonging to the serpin superfamily have emerged as protective elements that support the survival of the parasites. This report describes the crystal structure of ShSPI, a serpin from the trematode Schistosoma haematobium. The protein is exposed on the surface of invading cercaria as well as of adult worms, suggesting its involvement in the parasite-host interaction. While generally conforming to the well established serpin fold, the structure reveals several distinctive features, mostly concerning the helical subdomain of the protein. It is proposed that these peculiarities are related to the unique biological properties of a small serpin subfamily which is conserved among pathogenic schistosomes.
Also flagged:clopidogrelCYP2C19synthesismetabolismexcretioncholesterol
Journal Article2012-05-16No SnippetsPulley JM, Denny JC, Peterson JF, Bernard GR, Vnencak-Jones CL, Ramirez AH, Delaney JT, Bowton E, Brothers K, Johnson K, Crawford DC, Schildcrout J, Masys DR, Dilks HH, Wilke RA, Clayton EW, Shultz E, Laposata M, McPherson J, Jirjis JN, Roden DM.
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The promise of "personalized medicine" guided by an understanding of each individual's genome has been fostered by increasingly powerful and economical methods to acquire clinically relevant information. We describe the operational implementation of prospective genotyping linked to an advanced clinical decision-support system to guide individualized health care in a large academic health center. This approach to personalized medicine entails engagement between patient and health-care provider, identification of relevant genetic variations for implementation, assay reliability, point-of-care decision support, and necessary institutional investments. In one year, approximately 3,000 patients, most of whom were scheduled for cardiac catheterization, were genotyped on a multiplexed platform that included genotyping for CYP2C19 variants that modulate response to the widely used antiplatelet drug clopidogrel. These data are deposited into the electronic medical record (EMR), and point-of-care decision support is deployed when clopidogrel is prescribed for those with variant genotypes. The establishment of programs such as this is a first step toward implementing and evaluating strategies for personalized medicine.
Also flagged:cognitionandrogensandrogenandrogen receptorARhormone nuclear receptor
Journal Article2012-05-16No SnippetsOtto-Duessel M, He M, Jones JO.
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<h4>Introduction</h4>Androgens regulate a wide array of physiological processes, including male sexual development, bone and muscle growth, and behavior and cognition. Because androgens play a vital role in so many tissues, changes in androgen signaling are associated with a plethora of diseases. How such varied responses are achieved by a single stimulus is not well understood. Androgens act primarily through the androgen receptor (AR), a hormone nuclear receptor that is expressed in a select variety of tissues.<h4>Methods</h4>In order to gain a better understanding of how the tissue-selective effects of androgens are achieved, we performed a comparison of microarray data, using previously published datasets and several of our own microarray datasets. These datasets were derived from clinically relevant, AR-expressing tissues dissected from rodents treated with the full androgen dihydrotestosterone (DHT).<h4>Results</h4>We found that there is a diverse response to DHT, with very little overlap of androgen regulated genes in each tissue. Gene ontology analyses also indicated that, while several tissues regulate similar biological processes in response to DHT, most androgen regulated processes are specific to one or a few tissues. Thus, it appears that the disparate physiological effects mediated by androgens begin with widely varying effects on gene expression in different androgen-sensitive tissues.<h4>Conclusion</h4>The analysis completed in this study will lead to an improved understanding of how androgens mediate diverse, tissue-specific processes and better ways to assess the tissue-selective effects of AR modulators during drug development.
Also flagged:tumornasopharyngeal carcinomascell proliferationprimary tumormetastatic tumorscell growth
Journal Article2012-05-16No SnippetsChen CH, Shiu LY, Su LJ, Huang CY, Huang SC, Huang CC, Yin YF, Wang WS, Tsai HT, Fang FM, Chuang WC, Kang HC, Hwang CF.
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<h4>Background</h4>Nasopharyngeal carcinoma (NPC) is well-known for its highly metastatic characteristics, but little is known of its molecular mechanisms. New biomarkers that predict clinical outcome, in particular the ability of the primary tumor to develop metastatic tumors are urgently needed. The aim of this study is to investigate the role of FLJ10540 in human NPC development.<h4>Methods</h4>A bioinformatics approach was used to explore the potentially important regulatory genes involved in the growth/metastasis control of NPC. FLJ10540 was chosen for this study. Two co-expression strategies from NPC microarray were employed to identify the relationship between FLJ10540 and osteopontin. Quantitative-RT-PCR, immunoblotting, and immunohistochemistry analysis were used to investigate the mRNA and protein expression profiles of FLJ10540 and osteopontin in the normal and NPC tissues to confirm microarray results. TW01 and Hone1 NPC cells with overexpression FLJ10540 or siRNA to repress endogenous FLJ10540 were generated by stable transfection to further elucidate the molecular mechanisms of FLJ10540-elicited cell growth and metastasis under osteopontin stimulation.<h4>Results</h4>We found that osteopontin expression exhibited a positive correlation with FLJ10540 in NPC microarray. We also demonstrated comprehensively that FLJ10540 and osteopontin were not only overexpressed in NPC specimens, but also significantly correlated with advanced tumor and lymph node-metastasis stages, and had a poor 5-year survival rate, respectively. Stimulation of NPC parental cells with osteopontin results in an increase in FLJ10540 mRNA and protein expressions. Functionally, FLJ10540 transfectant alone, or stimulated with osteopontin, exhibited fast growth and increased metastasis as compared to vehicle control with or without osteopontin stimulation. Conversely, knockdown of FLJ10540 by siRNA results in the suppression of NPC cell growth and motility. Treatment with anti-CD44 antibodies in NPC parental cells not only resulted in a decrease of FLJ10540 protein, but also affected the abilities of FLJ10540-elicited cell growth and motility in osteopontin stimulated-NPC cells.<h4>Conclusions</h4>These findings suggest that FLJ10540 may be critical regulator of disease progression in NPC, and the underlying mechanism may involve in the osteopontin/CD44 pathway.
Voltage-dependent calcium and sodium channels mediating persistent inward currents (PICs) amplify the effects of synaptic inputs on the membrane potential and firing rate of motoneurons. CaPIC channels are thought to be relatively slow, whereas the NaPIC channels have fast kinetics. These different characteristics influence how synaptic inputs with different frequency content are amplified; the slow kinetics of Ca channels suggest that they can only contribute to amplification of low frequency inputs (<5 Hz). To characterize frequency-dependent amplification of excitatory postsynaptic potentials (EPSPs), we measured the averaged stretch-evoked EPSPs in cat medial gastrocnemius motoneurons in decerebrate cats at different subthreshold levels of membrane potential. EPSPs were produced by muscle spindle afferents activated by stretching the homonymous and synergist muscles at frequencies of 5-50 Hz. We adjusted the stretch amplitudes at different frequencies to produce approximately the same peak-to-peak EPSP amplitude and quantified the amount of amplification by expressing the EPSP integral at different levels of depolarization as a percentage of that measured with the membrane hyperpolarized. Amplification was observed at all stretch frequencies but generally decreased with increasing stretch frequency. However, in many cells the amount of amplification was greater at 10 Hz than at 5 Hz. Fast amplification was generally reduced or absent when the lidocaine derivative QX-314 was included in the electrode solution, supporting a strong contribution from Na channels. These results suggest that NaPICs can combine with CaPICs to enhance motoneuron responses to modulations of synaptic drive over a physiologically significant range of frequencies.
Also flagged:DIAPH3tumourtumoursDiaphanous-related formin-3cancerchromosome
Journal Article2012-05-16✓ 3 SnippetsHager MH, Morley S, Bielenberg DR, Gao S, Morello M, Holcomb IN, Liu W, Mouneimne G, Demichelis F, Kim J, Solomon KR, Adam RM, Isaacs WB, Higgs HN, Vessella RL, Di Vizio D, Freeman MR.
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S I O 001029)
…Only three genes, PCDH17, TDRD3 and DIAPH3, are focally deleted in all cancer subtypes.…
Results)
…Among the deletion peaks on chromosome 13, one containing three genes, protocadherin 17 (PCDH17), tudor domain-containing protein 3 (TDRD3) and DIAPH3, was located in a region common to three carcinomas (prostate, breast and hepatocellular, Fig 1A).…
Therapies for most malignancies are generally ineffective once metastasis occurs. While tumour cells migrate through tissues using diverse strategies, the signalling networks controlling such behaviours in human tumours are poorly understood. Here we define a role for the Diaphanous-related formin-3 (DIAPH3) as a non-canonical regulator of metastasis that restrains conversion to amoeboid cell behaviour in multiple cancer types. The DIAPH3 locus is close to RB1, within a narrow consensus region of deletion on chromosome 13q in prostate, breast and hepatocellular carcinomas. DIAPH3 silencing in human carcinoma cells destabilized microtubules and induced defective endocytic trafficking, endosomal accumulation of EGFR, and hyperactivation of EGFR/MEK/ERK signalling. Silencing also evoked amoeboid properties, increased invasion and promoted metastasis in mice. In human tumours, DIAPH3 down-regulation was associated with aggressive or metastatic disease. DIAPH3-silenced cells were sensitive to MEK inhibition, but showed reduced sensitivity to EGFR inhibition. These findings have implications for understanding mechanisms of metastasis, and suggest that identifying patients with chromosomal deletions at DIAPH3 may have prognostic value.
Sulfamate groups (NHSO(3)(-)) are important structural elements in the glycosaminoglycans (GAGs) heparin and heparan sulfate (HS). In this work, proton nuclear magnetic resonance (NMR) line-shape analysis is used to explore the solvent exchange properties of the sulfamate NH groups within heparin-related mono-, di-, tetra- and pentasaccharides as a function of pH and temperature. The results of these experiments identified a persistent hydrogen bond within the Arixtra (fondaparinux sodium) pentasaccharide between the internal glucosamine sulfamate NH and the adjacent 3-O-sulfo group. This discovery provides new insights into the solution structure of the Arixtra pentasaccharide and suggests that 3-O-sulfation of the heparin N-sulfoglucosamine (GlcNS) residues pre-organize the secondary structure in a way that facilitates binding to antithrombin-III. NMR studies of the GlcNS NH groups can provide important information about heparin structure complementary to that available from NMR spectral analysis of the carbon-bound protons.
The zinc finger antiviral protein (ZAP) is a host factor that mediates inhibition of viruses in the Filoviridae, Retroviridae and Togaviridae families. We previously demonstrated that ZAP blocks replication of Sindbis virus (SINV), the prototype Alphavirus in the Togaviridae family at an early step prior to translation of the incoming genome and that synergy between ZAP and one or more interferon stimulated genes (ISGs) resulted in maximal inhibitory activity. The present study aimed to identify those ISGs that synergize with ZAP to mediate Alphavirus inhibition. Using a library of lentiviruses individually expressing more than 350 ISGs, we screened for inhibitory activity in interferon defective cells with or without ZAP overexpression. Confirmatory tests of the 23 ISGs demonstrating the largest infection reduction in combination with ZAP revealed that 16 were synergistic. Confirmatory tests of all potentially synergistic ISGs revealed 15 additional ISGs with a statistically significant synergistic effect in combination with ZAP. These 31 ISGs are candidates for further mechanistic studies. The number and diversity of the identified ZAP-synergistic ISGs lead us to speculate that ZAP may play an important role in priming the cell for optimal ISG function.
Also flagged:cerebral infarctionMACMitral annulus calcificationdegenerative disordercalciummitral regurgitation
Journal Article2012-05-16✓ 1 SnippetNagai T, Kusano H, Hamabe A, Arakawa J, Konishi T, Hisadome H, Yoshida M, Tabata H, Uehata A.
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Mitral annulus calcification (MAC) has been recognized as a potent risk factor to cause cerebral infarction. There has been suggested possible linkage between mass on MAC and systemic embolic events. We report a case of cerebral infarction with newly developed mobile mass superimposed on MAC.
New conjugates of 18<i>β</i>- and 18α-glycyrrhizic acids (GAs) each containing two di- or <i>α</i>-methyl esters of L-aspartic acid in the carbohydrate part of the glycosides were synthesized by the activated ester method using the N-hydroxysuccinimide (HOSu) and N,N'-dicyclohexylcarbodiimide. It was found that the conjugate of 18<i>β</i>-GA with Asp(OMe)(OMe) (<b>4</b>) at a concentration of 250 μg/mL inhibited effectively RT of HIV-1 and the accumulation of virus antigen p24 in MT-4 cell culture (95-97 %) and protected cells from the cytopathogenic action of the virus.
Also flagged:HuntingtinHuntington diseaseHDneurodegenerative disorderpolyglutaminedeath
Journal Article2012-05-15✓ 5 SnippetsRatovitski T, Chighladze E, Arbez N, Boronina T, Herbrich S, Cole RN, Ross CA.
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Abstract)
…These data demonstrate that a number of key cellular functions and networks may be disrupted by abnormal interactions of expanded huntingtin and highlight proteins and pathways that may be involved in HD cellular pathogenesis and that may serve as therapeutic targets.…
Abstract)
…We found that proteins preferentially interacting with expanded huntingtin are enriched for intrinsically disordered proteins, consistent with previously suggested roles of such proteins in neurodegenerative disorders.…
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Huntington disease (HD) is a neurodegenerative disorder caused by an expansion of a polyglutamine repeat within the HD gene product, huntingtin. Huntingtin, a large (347 kDa) protein containing multiple HEAT repeats, acts as a scaffold for protein-protein interactions. Huntingtin-induced toxicity is believed to be mediated by a conformational change in expanded huntingtin, leading to protein misfolding and aggregation, aberrant protein interactions and neuronal cell death. While many non-systematic studies of huntingtin interactions have been reported, they were not designed to identify and quantify the changes in the huntingtin interactome induced by polyglutamine expansion. We used tandem affinity purification and quantitative proteomics to compare and quantify interactions of normal or expanded huntingtin isolated from a striatal cell line. We found that proteins preferentially interacting with expanded huntingtin are enriched for intrinsically disordered proteins, consistent with previously suggested roles of such proteins in neurodegenerative disorders. Our functional analysis indicates that proteins related to energy production, protein trafficking, RNA post-transcriptional modifications and cell death were significantly enriched among preferential interactors of expanded huntingtin. Expanded huntingtin interacted with many mitochondrial proteins, including AIFM1, consistent with a role for mitochondrial dysfunction in HD. Furthermore, expanded huntingtin interacted with the stress granule-associated proteins Caprin-1 and G3BP and redistributed to RNA stress granules under ER-stress conditions. These data demonstrate that a number of key cellular functions and networks may be disrupted by abnormal interactions of expanded huntingtin and highlight proteins and pathways that may be involved in HD cellular pathogenesis and that may serve as therapeutic targets.
…xplain 'classical' ferroportinhemochromatosisphenotypes in some…
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We report on a 46-year-old black man who resided in Alabama with normal transferrin saturation, mild hyperferritinemia, chronic hepatitis C, and 3+ iron in hepatocytes and Kupffer cells. Exome sequencing revealed heterozygosity for SLC40A1 D270V (exon 7, c.809A→T), a mutation previously reported only in 1 black patient with iron overload who resided in the Republic of South Africa. The present patient was also heterozygous for: heme transporter FLVCR1 novel allele P542S (exon 10, 1624C→T); FLVCR1 T544M (rs3207090); hemopexin (HPX) R371W (rs75307540); ferritin scavenger receptor (SCARA5) R471H (rs61737287); and transferrin receptor (TFRC) G420S (rs41295879). He had no HFE, TFR2,HJV, or HAMP mutations. D270V was not detected in 19 other African Americans with iron overload who resided in Alabama. The allele frequency of SLC40A1 D270V in 258 African American adults who participated in a health appraisal clinic was 0.0019 (95% confidence interval 0-0.0057). D270V could explain 'classical' ferroportin hemochromatosis phenotypes in some African Americans.
Also flagged:Factor V LeidenOvarian Cancerhypertrophic cardiomyopathycancerBRCAcolorectal cancer
Journal Article2012-05-15✓ 1 SnippetKlitzman R, Chung W, Marder K, Shanmugham A, Chin LJ, Stark M, Leu CS, Appelbaum PS.
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Many questions remain concerning whether, when, and how physicians order genetic tests, and what factors are involved in their decisions. We surveyed 220 internists from two academic medical centers about their utilization of genetic testing. Rates of genetic utilizations varied widely by disease. Respondents were most likely to have ordered tests for Factor V Leiden (16.8 %), followed by Breast/Ovarian Cancer (15.0 %). In the past 6 months, 65 % had counseled patients on genetic issues, 44 % had ordered genetic tests, 38.5 % had referred patients to a genetic counselor or geneticist, and 27.5 % had received ads from commercial labs for genetic testing. Only 4.5 % had tried to hide or disguise genetic information, and <2 % have had patients report genetic discrimination. Only 53.4 % knew of a geneticist/genetic counselor to whom to refer patients. Most rated their knowledge as very/somewhat poor concerning genetics (73.7 %) and guidelines for genetic testing (87.1 %). Most felt needs for more training on when to order tests (79 %), and how to counsel patients (82 %), interpret results (77.3 %), and maintain privacy (80.6 %). Physicians were more likely to have ordered a genetic test if patients inquired about genetic testing (p < .001), and if physicians had a geneticist/genetic counselor to whom to refer patients (p < .002), had referred patients to a geneticist/genetic counselor in the past 6 months, had more comfort counseling patients about testing (p < .019), counseled patients about genetics, larger practices (p < .032), fewer African-American patients (p < .027), and patients who had reported genetic discrimination (p < .044). In a multiple logistic regression, ordering a genetic test was associated with patients inquiring about testing, having referred patients to a geneticist/genetic counselor and knowing how to order tests. These data suggest that physicians recognize their knowledge deficits, and are interested in training. These findings have important implications for future medical practice, research, and education.
Also flagged:neurocognitive disordercerebrovascular diseaseglucosemetabolismimpairedtolerance
Journal Article2012-05-15No SnippetsNakamoto BK, Jahanshad N, McMurtray A, Kallianpur KJ, Chow DC, Valcour VG, Paul RH, Marotz L, Thompson PM, Shikuma CM.
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HIV-associated neurocognitive disorder remains prevalent in HIV-infected individuals despite effective antiretroviral therapy. As these individuals age, comorbid cerebrovascular disease will likely impact cognitive function. Effective tools to study this impact are needed. This study used diffusion tensor imaging (DTI) to characterize brain microstructural changes in HIV-infected individuals with and without cerebrovascular risk factors. Diffusion-weighted MRIs were obtained in 22 HIV-infected subjects aged 50 years or older (mean age = 58 years, standard deviation = 6 years; 19 males, three females). Tensors were calculated to obtain fractional anisotropy (FA) and mean diffusivity (MD) maps. Statistical comparisons accounting for multiple comparisons were made between groups with and without cerebrovascular risk factors. Abnormal glucose metabolism (i.e., impaired fasting glucose, impaired glucose tolerance, or diabetes mellitus) was associated with significantly higher MD (false discovery rate (FDR) critical p value = 0.008) and lower FA (FDR critical p value = 0.002) in the caudate and lower FA in the hippocampus (FDR critical p value = 0.004). Pearson correlations were performed between DTI measures in the caudate and hippocampus and age- and education-adjusted composite scores of global cognitive function, memory, and psychomotor speed. There were no detectable correlations between the neuroimaging measures and measures of cognition. In summary, we demonstrate that brain microstructural abnormalities are associated with abnormal glucose metabolism in the caudate and hippocampus of HIV-infected individuals. Deep gray matter structures and the hippocampus may be vulnerable in subjects with comorbid abnormal glucose metabolism, but our results should be confirmed in further studies.
Also flagged:coronary artery diseasepathogenesischolesterolhypertensionobesityMyocardial Infarction
Journal Article2012-05-15No SnippetsRoberts R, Stewart AF.
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Coronary artery disease (CAD) is still the number-one killer in the world, and clinical trials indicate that it is preventable. Mortality and morbidity can be reduced by at least 30% to 40% by treating known risk factors. Genetic susceptibility is claimed to account for 50% of predisposition. The challenge of preventing CAD in this century, as claimed by some investigators, will require a more comprehensive prevention and treatment of environmental and genetic risk factors. Part of that challenge has been met by genome-wide association studies, which have identified 36 genetic variants with increased risk for CAD. All of these genetic variants have reached genome-wide significance (5 × 10(-8) ) and replicate in independent populations with large sample sizes. More than 50% of these variants occur in >50% of the population, with 10 occurring in >75% of the population. The challenge and the opportunity lie in the observation that >66% of these risk variants do not mediate their risk through known conventional risk factors. These results suggest that genetic predisposition for CAD is conferred by common DNA variants and many factors contributing to the pathogenesis of CAD are yet to be determined. Comprehensive prevention of CAD will most likely require combating genetic and environmental risk factors. We are on the cusp of genetic screening, and new therapeutic targets are becoming available to manage both genetic and environmental risk factors for CAD.
Also flagged:Transducer of regulated CREB-binding proteinsHuntington's diseaseHDneurological disorderglutamineTransducers of Regulated cAMP response element-binding
Journal Article2012-05-15✓ 5 SnippetsChaturvedi RK, Hennessey T, Johri A, Tiwari SK, Mishra D, Agarwal S, Kim YS, Beal MF.
In-Text Gene Mentions
Abstract)
…Lastly, knockdown of Htt prevents transcriptional repression of TORC1 and CREB in Htt striatal cells.…
Abstract)
…Huntington's disease (HD) is an incurable neurological disorder caused by an abnormal glutamine repeat expansion in the huntingtin (Htt) protein.…
Abstract)
…TORC1 overexpression in wild-type (WT) and Htt striatal cells increased CREB mRNA and protein levels, PGC-1 promoter activity, mRNA expression of the PGC-1, NRF-1, Tfam and CytC genes, mitochondrial DNA content, mitochondrial activity and mitochondrial membrane potential.…
Abstract)
…We found significantly decreased TORC1 expression levels in STHdhQ111 cells expressing mutant Htt, in the striatum of NLS-N171-82Q, R6/2 and HdhQ111 HD transgenic mice and in postmortem striatal tissue from HD patients.…
Abstract)
…in the huntingtin (Htt) protein.…
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Huntington's disease (HD) is an incurable neurological disorder caused by an abnormal glutamine repeat expansion in the huntingtin (Htt) protein. In the present studies, we investigated the role of Transducers of Regulated cAMP response element-binding (CREB) protein activity (TORCs) in HD, since TORCs play an important role in the expression of the transcriptional co-regulator peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α), whose expression is impaired in HD. We found significantly decreased TORC1 expression levels in STHdhQ111 cells expressing mutant Htt, in the striatum of NLS-N171-82Q, R6/2 and HdhQ111 HD transgenic mice and in postmortem striatal tissue from HD patients. TORC1 overexpression in wild-type (WT) and Htt striatal cells increased CREB mRNA and protein levels, PGC-1α promoter activity, mRNA expression of the PGC-1α, NRF-1, Tfam and CytC genes, mitochondrial DNA content, mitochondrial activity and mitochondrial membrane potential. TORC1 overexpression also increased the resistance of striatal cells to 3-nitropropionic (3-NP) acid-mediated toxicity. In cultured WT and mutant Htt striatal cells, small hairpin RNA-mediated TORC1 knockdown resulted in decreased PGC-1α expression and increased susceptibility to 3-NP-induced toxicity. Overexpression of PGC-1α partially prevented TORC1 knockdown-mediated increased susceptibility of Htt striatal cells to 3-NP. Specific knockdown of TORC1 in the striatum of NLS-N171-82Q HD transgenic mice induced neurodegeneration. Lastly, knockdown of Htt prevents transcriptional repression of TORC1 and CREB in Htt striatal cells. These findings show that impaired expression and function of TORC1, which results in a reduction in PGC-1α, plays an important role in mitochondrial dysfunction in HD.
Also flagged:Cap-binding proteinsscavenger decapping enzyme7-methylguanosinesynthesisbindingeIF4E
Journal Article2012-05-15No SnippetsSzczepaniak SA, Zuberek J, Darzynkiewicz E, Kufel J, Jemielity J.
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Cap-binding proteins have been routinely isolated using m⁷GTP-Sepharose; however, this resin is inefficient for proteins such as DcpS (scavenger decapping enzyme), which interacts not only with the 7-methylguanosine, but also with the second cap base. In addition, DcpS purification may be hindered by the reduced resin capacity due to the ability of DcpS to hydrolyze m⁷GTP. Here, we report the synthesis of new affinity resins, m⁷GpCH₂pp- and m⁷GpCH₂ppA-Sepharoses, with attached cap analogs resistant to hydrolysis by DcpS. Biochemical tests showed that these matrices, as well as a hydrolyzable m⁷GpppA-Sepharose, bind recombinant mouse eIF4E²⁸⁻²¹⁷ specifically and at high capacity. In addition, purification of cap-binding proteins from yeast extracts confirmed the presence of all expected cap-binding proteins, including DcpS in the case of m⁷GpCH₂pp- and m⁷GpCH₂ppA-Sepharoses. In contrast, binding studies in vitro demonstrated that recombinant human DcpS efficiently bound only m⁷GpCH₂ppA-Sepharose. Our data prove the applicability of these novel resins, especially m⁷GpCH₂ppA-Sepharose, in biochemical studies such as the isolation and identification of cap-binding proteins from different organisms.
Also flagged:Ironmetabolismerythropoiesishemephagocytosiscatabolism
Journal Article2012-05-15✓ 1 SnippetBeaumont C, Karim Z.
In-Text Gene Mentions
Abstract)
…adult forms ofhemochromatosiswhereas a defect…
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About 60% of body iron is associated with hemoglobin in circulating red blood cells and daily erythropoiesis requires about 25 to 30mg iron per day. This iron is provided by macrophages through recycling of heme iron following phagocytosis of senescent red blood cells and heme catabolism. Intestinal iron absorption (1 to 2mg per day) only compensates for daily iron losses. Hepcidin, a 25 amino-acid peptide synthesized in hepatocytes, secreted in plasma and rapidly removed in urines, is a negative regulator of both intestinal iron absorption and heme iron recycling by macrophages. Hepcidin synthesis is stimulated by iron or by inflammation (mostly by IL-6) and is repressed by iron deficiency and by all conditions that stimulate bone marrow erythropoiesis such as anemia, bleeding, hemolysis, dyserythropoiesis or erythropoietin injections. A defect in the activation of hepcidin normally triggered by iron excess is the underlying mechanism for all juvenile or adult forms of hemochromatosis whereas a defect in hepcidin repression is responsible for an iron deficiency iron refractory anemia (IRIDA). Reduced hepcidin filtration in renal insufficiency contributes to the associated anemia and stimulation of hepcidin synthesis by inflammation is a major determinant of the anemia of chronic disorders. New therapeutic perspectives are currently underway such as the development of agonists or antagonists of hepcidin or siRNA approaches aiming at reducing hepcidin synthesis. The validation of hepcidin assays in a near future will allow identifying the patients most likely to benefit from intravenous iron therapy.
Also flagged:Cystatin aMyocilinMYOCglycoproteinglaucomacalpain II
Journal Article2012-05-15✓ 1 SnippetKennedy KD, AnithaChristy SA, Buie LK, Borrás T.
In-Text Gene Mentions
Results)
…and Prostacyclin synthase,PTGIS).…
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Myocilin (MYOC) is a 504 aa secreted glycoprotein induced by stress factors in the trabecular meshwork tissue of the eye, where it was discovered. Mutations in MYOC are linked to glaucoma. The glaucoma phenotype of each of the different MYOC mutation varies, but all of them cause elevated intraocular pressure (IOP). In cells, forty percent of wild-type MYOC is cleaved by calpain II, a cysteine protease. This proteolytic process is inhibited by MYOC mutants. In this study, we investigated the molecular mechanisms by which MYOC mutants cause glaucoma. We constructed adenoviral vectors with variants Q368X, R342K, D380N, K423E, and overexpressed them in human trabecular meshwork cells. We analyzed expression profiles with Affymetrix U133Plus2 GeneChips using wild-type and null viruses as controls. Analysis of trabecular meshwork relevant mechanisms showed that the unfolded protein response (UPR) was the most affected. Search for individual candidate genes revealed that genes that have been historically connected to trabecular meshwork physiology and pathology were altered by the MYOC mutants. Some of those had known MYOC associations (MMP1, PDIA4, CALR, SFPR1) while others did not (EDN1, MGP, IGF1, TAC1). Some, were top-changed in only one mutant (LOXL1, CYP1B1, FBN1), others followed a mutant group pattern. Some of the genes were new (RAB39B, STC1, CXCL12, CSTA). In particular, one selected gene, the cysteine protease inhibitor cystatin A (CSTA), was commonly induced by all mutants and not by the wild-type. Subsequent functional analysis of the selected gene showed that CSTA was able to reduce wild-type MYOC cleavage in primary trabecular meshwork cells while an inactive mutated CSTA was not. These findings provide a new molecular understanding of the mechanisms of MYOC-causative glaucoma and reveal CSTA, a serum biomarker for cancer, as a potential biomarker and drug for the treatment of MYOC-induced glaucoma.
Also flagged:butyrateShort-chain fatty acidscell differentiationcell cyclehistone deacetylasesHDACs
Journal Article2012-05-15No SnippetsWu S, Li RW, Li W, Li CJ.
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Short-chain fatty acids (SCFAs), especially butyrate, affect cell differentiation, proliferation, and motility. Butyrate also induces cell cycle arrest and apoptosis through its inhibition of histone deacetylases (HDACs). In addition, butyrate is a potent inducer of histone hyper-acetylation in cells. Therefore, this SCFA provides an excellent in vitro model for studying the epigenomic regulation of gene expression induced by histone acetylation. In this study, we analyzed the differential in vitro expression of genes induced by butyrate in bovine epithelial cells by using deep RNA-sequencing technology (RNA-seq). The number of sequences read, ranging from 57,303,693 to 78,933,744, were generated per sample. Approximately 11,408 genes were significantly impacted by butyrate, with a false discovery rate (FDR) <0.05. The predominant cellular processes affected by butyrate included cell morphological changes, cell cycle arrest, and apoptosis. Our results provided insight into the transcriptome alterations induced by butyrate, which will undoubtedly facilitate our understanding of the molecular mechanisms underlying butyrate-induced epigenomic regulation in bovine cells.
Also flagged:IronVentricularRepolarizationBeta-ThalassemiaBeta-thalassemia majorhemogolinopathy
Journal Article2012-05-15✓ 1 SnippetKayrak M, Acar K, Gul EE, Ozbek O, Abdulhalikov T, Sonmez O, Alibaşiç H.
In-Text Gene Mentions
Discussion)
…in patients withhemochromatosis[ 25 ].…
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Previous studies have demonstrated impaired ventricular repolarization in patients with β-TM. However, the effect of iron overload with cardiac T2* magnetic resonance imaging (MRI) on cardiac repolarization remains unclear yet. We aimed to examine relationship between repolarization parameters and iron loading using cardiac T2* MRI in asymptomatic β-TM patients. Twenty-two β-TM patients and 22 age- and gender-matched healthy controls were enrolled to the study. From the 12-lead surface electrocardiography, regional and transmyocardial repolarization parameters were evaluated manually by two experienced cardiologists. All patients were also undergone MRI for cardiac T2* evaluation. Cardiac T2* score <20 msec was considered as iron overload status. Of the QT parameters, QT duration, corrected QT interval, and QT peak duration were significantly longer in the β-TM group compared to the healthy controls. T(p) - T(e) and T(p) - T(e) dispersions were also significantly prolonged in β-TM group compared to healthy controls. (T(p) - T(e))/QT was similar between groups. There was no correlation between repolarization parameters and cardiac T2* MRI values. In conclusion, although repolarization parameters were prolonged in asymptomatic β-TM patients compared with control, we could not find any relation between ECG findings and cardiac iron load.
Also flagged:polyglutamineneurodegenerative diseaseHDpeptidesNucleationpolyglutamine (polyQ) diseases
Journal Article2012-05-14✓ 5 SnippetsSugaya K, Matsubara S.
In-Text Gene Mentions
Introduction)
…Soluble oligomeric aggregate of mutant huntingtin (htt) protein in HD was also found in tissues from individuals with HD [16].…
Introduction)
…of mutant huntingtin (htt) protein in HD…
Introduction)
…nucleation of mutanthttproteins in a…
Methods)
…of mutant huntingtinhttproteins in a…
Methods)
…of the mutanthttprotein.…
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<h4>Background</h4>Despite enormous progress in elucidating the biophysics of aggregation, no cause-and-effect relationship between protein aggregation and neurodegenerative disease has been unequivocally established. Here, we derived several risk-based stochastic kinetic models that assess genotype/phenotype correlations in patients with Huntington's disease (HD) caused by the expansion of a CAG repeat. Fascinating disease-specific aspects of HD include the polyglutamine (polyQ)-length dependence of both age at symptoms onset and the propensity of the expanded polyQ protein to aggregate. In vitro, aggregation of polyQ peptides follows a simple nucleated growth polymerization pathway. Our models that reflect polyQ aggregation kinetics in a nucleated growth polymerization divided aggregate process into the length-dependent nucleation and the nucleation-dependent elongation. In contrast to the repeat-length dependent variability of age at onset, recent studies have shown that the extent of expansion has only a subtle effect on the rate of disease progression, suggesting possible differences in the mechanisms underlying the neurodegenerative process.<h4>Results</h4>Using polyQ-length as an index, these procedures enabled us for the first time to establish a quantitative connection between aggregation kinetics and disease process, including onset and the rate of progression. Although the complexity of disease process in HD, the time course of striatal neurodegeneration can be precisely predicted by the mathematical model in which neurodegeneration occurs by different mechanisms for the initiation and progression of disease processes. Nucleation is sufficient to initiate neuronal loss as a series of random events in time. The stochastic appearance of nucleation in a cell population acts as the constant risk of neuronal cell damage over time, while elongation reduces the risk by nucleation in proportion to the increased extent of the aggregates during disease progression.<h4>Conclusions</h4>Our findings suggest that nucleation is a critical step in gaining toxic effects to the cell, and provide a new insight into the relationship between polyQ aggregation and neurodegenerative process in HD.
Also flagged:TDP-43fragile X mental retardation proteinFMRPSIRT143 kDa transactive response DNA-binding proteinneurodegenerative diseases
Journal Article2012-05-14✓ 5 SnippetsYu Z, Fan D, Gui B, Shi L, Xuan C, Shan L, Wang Q, Shang Y, Wang Y.
In-Text Gene Mentions
Abstract)
…Here, we report that TDP-43 is physically associated with fragile X mental retardation protein (FMRP) and Staufen (STAU1) to form a functional complex.…
Abstract)
…RNA-immunoprecipitation (RIP) and RNA pull-down assays demonstrated that TDP-43/FMRP/STAU1 specifically binds to the 3'-UTR of SIRT1 mRNA, and that knockdown the expression of any one of these three proteins resulted in the reduction of SIRT1 mRNA and protein.…
Abstract)
…survival. Indeed , depletion of TDP-43/FMRP/STAU1 sensitizes cells to…
Title)
…ation protein (FMRP)/Staufen (STAU1) and regulates SIRT1…
Abstract)
…(FMRP) and Staufen (STAU1) to form a…
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Despite the identification of the 43 kDa transactive response DNA-binding protein (TDP-43) as a major pathological signatory protein in a wide range of neurodegenerative diseases, the mechanistic role of TDP-43 in neurodegenerative disorders is still poorly understood. Here, we report that TDP-43 is physically associated with fragile X mental retardation protein (FMRP) and Staufen (STAU1) to form a functional complex. Differential microarray analysis revealed that the expression of a collection of functionally important genes including Sirtuin (SIRT1) is regulated by this complex. RNA-immunoprecipitation (RIP) and RNA pull-down assays demonstrated that TDP-43/FMRP/STAU1 specifically binds to the 3'-UTR of SIRT1 mRNA, and that knockdown the expression of any one of these three proteins resulted in the reduction of SIRT1 mRNA and protein. SIRT1 is implicated in double-stranded DNA break repair and is required for cell survival. Indeed, depletion of TDP-43/FMRP/STAU1 sensitizes cells to apoptosis and DNA damages. Collectively, our results revealed a molecular mechanism for the cellular function of TDP-43 and might shed new light on the understanding of the mechanistic role of TDP-43 in neurodegenerative diseases.
Also flagged:photoprotectionphotosystemchlorophyllmembranecharge-transferlight-harvesting complexes
Journal Article2012-05-14No SnippetsAmarnath K, Zaks J, Park SD, Niyogi KK, Fleming GR.
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Photosynthetic organisms avoid photodamage to photosystem II (PSII) in variable light conditions via a suite of photoprotective mechanisms called nonphotochemical quenching (NPQ), in which excess absorbed light is dissipated harmlessly. To quantify the contributions of different quenching mechanisms to NPQ, we have devised a technique to measure the changes in chlorophyll fluorescence lifetime as photosynthetic organisms adapt to varying light conditions. We applied this technique to measure the fluorescence lifetimes responsible for the predominant, rapidly reversible component of NPQ, qE, in living cells of Chlamydomonas reinhardtii. Application of high light to dark-adapted cells of C. reinhardtii led to an increase in the amplitudes of 65 ps and 305 ps chlorophyll fluorescence lifetime components that was reversed after the high light was turned off. Removal of the pH gradient across the thylakoid membrane linked the changes in the amplitudes of the two components to qE quenching. The rise times of the amplitudes of the two components were significantly different, suggesting that the changes are due to two different qE mechanisms. We tentatively suggest that the changes in the 65 ps component are due to charge-transfer quenching in the minor light-harvesting complexes and that the changes in the 305 ps component are due to aggregated light-harvesting complex II trimers that have detached from PSII. We anticipate that this technique will be useful for resolving the various mechanisms of NPQ and for quantifying the timescales associated with these mechanisms.
Also flagged:Wingless/Int (Wnttranscription factorAtoh1secretorycell differentiationWnt
Journal Article2012-05-14✓ 1 SnippetDurand A, Donahue B, Peignon G, Letourneur F, Cagnard N, Slomianny C, Perret C, Shroyer NF, Romagnolo B.
In-Text Gene Mentions
Text
…Olfm4…
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Intestinal epithelium has the capacity to self-renew and generate differentiated cells through the existence of two types of epithelial stem cells: active crypt base columnar cells (CBCs) and quiescent +4 cells. The behaviors of these cells are regulated both by intrinsic programs and by extrinsic signals sent by neighboring cells, which define the niche. It is clear that the β-catenin pathway acts as an essential intrinsic signal for the maintenance and proliferation of CBC, and it was recently proposed that Paneth cells provide a crucial niche by secreting Wingless/Int (Wnt) ligands. Here, we examined the effect of disrupting the intestinal stem cell niche by inducible deletion of the transcription factor Math1 (Atoh1), an essential driver of secretory cell differentiation. We found that complete loss of Paneth cells attributable to Math1 deficiency did not perturb the crypt architecture and allowed the maintenance and proliferation of CBCs. Indeed, Math1-deficient crypt cells tolerated in vivo Paneth cell loss and maintained active β-catenin signaling but could not grow ex vivo without exogenous Wnt, implying that, in vivo, underlying mucosal cells act as potential niche. Upon irradiation, Math1-deficient crypt cells regenerated and CBCs continued cycling. Finally, CBC stem cells deficient in adenomatous polyposis coli (Apc) and Math1 were able to promote intestinal tumorigenesis. We conclude that in vivo, Math1-deficient crypts counteract the absence of Paneth cell-derived Wnts and prevent CBC stem cell exhaustion.
The differentiation of gametes involves dramatic changes to chromatin, affecting transcription, meiosis, and cell morphology. Sporulation in Saccharomyces cerevisiae shares many chromatin features with spermatogenesis, including a 10-fold compaction of the nucleus. To identify new proteins involved in spore nuclear organization, we purified chromatin from mature spores and discovered a significant enrichment of the linker histone (Hho1). The function of Hho1 has proven to be elusive during vegetative growth, but here we demonstrate its requirement for efficient sporulation and full compaction of the spore genome. Hho1 chromatin immunoprecipitation followed by sequencing (ChIP-seq) revealed increased genome-wide binding in mature spores and provides novel in vivo evidence of the linker histone binding to nucleosomal linker DNA. We also link Hho1 function to the transcription factor Ume6, the master repressor of early meiotic genes. Hho1 and Ume6 are depleted during meiosis, and analysis of published ChIP-chip data obtained during vegetative growth reveals a high binding correlation of both proteins at promoters of early meiotic genes. Moreover, Ume6 promotes binding of Hho1 to meiotic gene promoters. Thus, Hho1 may play a dual role during sporulation: Hho1 and Ume6 depletion facilitates the onset of meiosis via activation of Ume6-repressed early meiotic genes, whereas Hho1 enrichment in mature spores contributes to spore genome compaction.
Also flagged:guidance receptordeleted in colorectal canceraxonsmorpholinooligonucleotidesaxon
Journal Article2012-05-14✓ 5 SnippetsGao J, Zhang C, Yang B, Sun L, Zhang C, Westerfield M, Peng G.
In-Text Gene Mentions
S I O 001029)
…These data show that Dcc regulates polarized axon initiation and asymmetric outgrowth of neurons in a vertebrate forebrain.…
Abstract)
…These experiments provide the first evidence that Dcc regulates polarized axon initiation and asymmetric outgrowth of forebrain neurons in vertebrates.…
Abstract)
…DCC (deleted in colorectal cancer…
Introduction)
…DCC, deleted in colorectal cancer…
Abstract)
…The guidance receptorDCC(deleted in colorectal…
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The guidance receptor DCC (deleted in colorectal cancer) ortholog UNC-40 regulates neuronal asymmetry development in Caenorhabditis elegans, but it is not known whether DCC plays a role in the specification of neuronal polarity in vertebrates. To examine the roles of DCC in neuronal asymmetry regulation in vertebrates, we studied zebrafish anterior dorsal telencephalon (ADt) neuronal axons. We generated transgenic zebrafish animals expressing the photo-convertible fluorescent protein Kaede in ADt neurons and then photo-converted Kaede to label specifically the ADt neuron axons. We found that ADt axons normally project ventrally. Knock down of Dcc function by injecting antisense morpholino oligonucleotides caused the ADt neurons to project axons dorsally. To examine the axon projection pattern of individual ADt neurons, we labeled single ADt neurons using a forebrain-specific promoter to drive fluorescent protein expression. We found that individual ADt neurons projected axons dorsally or formed multiple processes after morpholino knock down of Dcc function. We further found that knock down of the Dcc ligand, Netrin1, also caused ADt neurons to project axons dorsally. Knockdown of Neogenin1, a guidance receptor closely related to Dcc, enhanced the formation of aberrant dorsal axons in embryos injected with Dcc morpholino. These experiments provide the first evidence that Dcc regulates polarized axon initiation and asymmetric outgrowth of forebrain neurons in vertebrates.
Also flagged:Hepatocellular carcinomacancerdeathmitogen-activated protein kinaseMAPKp38
Journal Article2012-05-14✓ 1 SnippetNakagawa H, Maeda S.
In-Text Gene Mentions
Introduction)
…include alcoholic hepatitis,hemochromatosis, and nonalcoholic steatohepat…
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Hepatocellular carcinoma (HCC) is the third most common cause of cancer mortality. Short-term prognosis of patients with HCC has improved recently due to advances in early diagnosis and treatment, but long-term prognosis is still unsatisfactory. Therefore, obtaining a further understanding of the molecular carcinogenic mechanisms and the unique pathogenic biology of HCC is important. The most characteristic process in hepatocarcinogenesis is underlying chronic liver injury, which leads to repeated cycles of hepatocyte death, inflammation, and compensatory proliferation and subsequently provides a mitogenic and mutagenic environment leading to the development of HCC. Recent in vivo studies have shown that the stress-activated mitogen-activated protein kinase (MAPK) cascade converging on c-Jun NH(2)-terminal kinase (JNK) and p38 plays a central role in these processes, and it has attracted considerable attention as a therapeutic target. However, JNK and p38 have complex functions and a wide range of cellular effects. In addition, crosstalk with each other and the nuclear factor-kappaB pathway further complicate these functions. A full understanding is essential to bring these observations into clinical settings. In this paper, we discuss the latest findings regarding the mechanisms of liver injury and hepatocarcinogenesis focusing on the role of the stress-activated MAPK pathway.
Also flagged:pathogenesisneurodegenerative diseasesneurodegenerative disorderpolyglutamineglutamineHD
Journal Article2012-05-14✓ 3 SnippetsLi XJ, Li S.
In-Text Gene Mentions
Abstract)
…Huntington's disease is a well-characterized neurodegenerative disorder that is caused by expansion of a CAG repeat, which results in expansion of a polyglutamine tract in the N-terminal region of huntingtin (HTT).…
Abstract)
…By comparing the neuropathology of transgenic HD mouse, pig, and monkey models, we found that mutant HTT is more toxic to larger animals than mice, and larger animals also show neuropathology that has not been uncovered by transgenic mouse models.…
Abstract)
…region of huntingtin (HTT).…
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Transgenic animal models have revealed much about the pathogenesis of age-dependent neurodegenerative diseases and proved to be a useful tool for uncovering therapeutic targets. Huntington's disease is a well-characterized neurodegenerative disorder that is caused by expansion of a CAG repeat, which results in expansion of a polyglutamine tract in the N-terminal region of huntingtin (HTT). Similar CAG/glutamine expansions are also found to cause eight other neurodegenerative diseases that affect distinct brain regions in an age-dependent manner. Identification of this CAG/glutamine expansion has led to the generation of a variety of transgenic animal models. Of these different animal models, transgenic mice have been investigated extensively, and they show similar neuropathology and phenotypes as seen in their respective diseases. The common pathological hallmark of age-dependent neurodegeneration is the formation of aggregates or inclusions consisting of misfolded proteins in the affected brain regions; however, overt or striking neurodegeneration and apoptosis have not been reported in most transgenic mouse models for age-dependent diseases, including HD. By comparing the neuropathology of transgenic HD mouse, pig, and monkey models, we found that mutant HTT is more toxic to larger animals than mice, and larger animals also show neuropathology that has not been uncovered by transgenic mouse models. This review will discuss the importance of transgenic large animal models for analyzing the pathogenesis of neurodegenerative diseases and developing effective treatments.
The composition of the gut microbiota is affected by environmental factors as well as host genetics. Iron is one of the important elements essential for bacterial growth, thus we hypothesized that changes in host iron homeostasis, may affect the luminal iron content of the gut and thereby the composition of intestinal bacteria. The iron regulatory protein 2 (Irp2) and one of the genes mutated in hereditary hemochromatosis Hfe , are both proteins involved in the regulation of systemic iron homeostasis. To test our hypothesis, fecal metal content and a selected spectrum of the fecal microbiota were analyzed from Hfe-/-, Irp2-/- and their wild type control mice. Elevated levels of iron as well as other minerals in feces of Irp2-/- mice compared to wild type and Hfe-/- mice were observed. Interestingly significant variation in the general fecal-bacterial population-patterns was observed between Irp2-/- and Hfe-/- mice. Furthermore the relative abundance of five species, mainly lactic acid bacteria, was significantly different among the mouse lines. Lactobacillus (L.) murinus and L. intestinalis were highly abundant in Irp2-/- mice, Enterococcus faecium species cluster and a species most similar to Olsenella were highly abundant in Hfe-/- mice and L. johnsonii was highly abundant in the wild type mice. These results suggest that deletion of iron metabolism genes in the mouse host affects the composition of its intestinal bacteria. Further studying the relationship between gut microbiota and genetic mutations affecting systemic iron metabolism in human should lead to clinical implications.
Also flagged:BRCA1H2AXautosomal dominant neurodegenerative disordercognitive declineHDHuntingtin
Journal Article2012-05-13✓ 5 SnippetsJeon GS, Kim KY, Hwang YJ, Jung MK, An S, Ouchi M, Ouchi T, Kowall N, Lee J, Ryu H.
In-Text Gene Mentions
Abstract)
…Neuronal DNA damage is one of the major features of neurodegeneration in HD, but it is not known how it arises or relates to the triplet repeat expansion mutation in the Htt gene.…
Abstract)
…Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder of mid-life onset characterized by involuntary movements and progressive cognitive decline caused by a CAG repeat expansion in exon 1 of the Huntingtin (Htt) gene.…
Abstract)
…mutation in theHttgene.…
Abstract)
…the Huntingtin (Htt) gene.…
Text
…Htt…
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Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder of mid-life onset characterized by involuntary movements and progressive cognitive decline caused by a CAG repeat expansion in exon 1 of the Huntingtin (Htt) gene. Neuronal DNA damage is one of the major features of neurodegeneration in HD, but it is not known how it arises or relates to the triplet repeat expansion mutation in the Htt gene. Herein, we found that imbalanced levels of non-phosphorylated and phosphorylated BRCA1 contribute to the DNA damage response in HD. Notably, nuclear foci of γ-H2AX, the molecular component that recruits various DNA damage repair factors to damage sites including BRCA1, were deregulated when DNA was damaged in HD cell lines. BRCA1 specifically interacted with γ-H2AX via the BRCT domain, and this association was reduced in HD. BRCA1 overexpression restored γ-H2AX level in the nucleus of HD cells, while BRCA1 knockdown reduced the spatiotemporal propagation of γ-H2AX foci to the nucleoplasm. The deregulation of BRCA1 correlated with an abnormal nuclear distribution of γ-H2AX in striatal neurons of HD transgenic (R6/2) mice and BRCA1(+/-) mice. Our data indicate that BRCA1 is required for the efficient focal recruitment of γ-H2AX to the sites of neuronal DNA damage. Taken together, our results show that BRCA1 directly modulates the spatiotemporal dynamics of γ-H2AX upon genotoxic stress and serves as a molecular maker for neuronal DNA damage response in HD.
Also flagged:ironmetabolismiron transportershemeiron deficiencyiron deficiency anemia
Journal Article2012-05-13✓ 3 SnippetsLipiński P, Styś A, Starzyński RR.
In-Text Gene Mentions
S I O 001029)
…HFE is a positive modulator of Hamp transcription, which, when defective, leads to hemochromatosis (HH) in humans and a HH-like phenotype in knockout animal models.…
S I O 001029)
…The hereditary hemochromatosis protein, HFE, which is responsible for type 1 hemochromatosis, was identified over 15 years ago [98].…
S I O 001029)
…Moreover, new factors that are involved in hepcidin expression, including proteins found to be mutated in various types of hemochromatosis (HFE, HJV, TfR2) or anemia (TMPRSS6), and transcription factors (SMAD4, STAT3), emerge each year.…
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Molecular iron metabolism and its regulation are least well understood in the fetal and early postnatal periods of mammalian ontogenic development. The scope of this review is to summarize recent progress in uncovering the molecular mechanisms of fetal iron homeostasis, introduce the molecules involved in iron transfer across the placenta, and briefly explain the role of iron transporters in the absorption of this microelement during early postnatal life. These issues are discussed and parallels are drawn with the relatively well-established system for elemental and heme iron regulation in adult mammals. We conclude that detailed investigations into the regulatory mechanisms of iron metabolism at early stages of development are required in order to optimize strategies to prevent neonatal iron deficiency. We propose that newborn piglets represent a suitable animal model for studies on iron deficiency anemia in neonates.
Also flagged:tumortumorsbreast cancerscancerscancerbreast cancer
Journal Article2012-05-13No SnippetsSubramanian A, Shackney S, Schwartz R.
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Tumorigenesis can in principle result from many combinations of mutations, but only a few roughly equivalent sequences of mutations, or "progression pathways," seem to account for most human tumors. Phylogenetics provides a promising way to identify common progression pathways and markers of those pathways. This approach, however, can be confounded by the high heterogeneity within and between tumors, which makes it difficult to identify conserved progression stages or organize them into robust progression pathways. To tackle this problem, we previously developed methods for inferring progression stages from heterogeneous tumor profiles through computational unmixing. In this paper, we develop a novel pipeline for building trees of tumor evolution from the unmixed tumor data. The pipeline implements a statistical approach for identifying robust progression markers from unmixed tumor data and calling those markers in inferred cell states. The result is a set of phylogenetic characters and their assignments in progression states to which we apply maximum parsimony phylogenetic inference to infer tumor progression pathways. We demonstrate the full pipeline on simulated and real comparative genomic hybridization (CGH) data, validating its effectiveness and making novel predictions of major progression pathways and ancestral cell states in breast cancers.
Also flagged:breast tumortryptophan-catabolizing enzymeindoleamine 2,3-dioxygenaseIDO1tumortumors
Journal Article2012-05-13No SnippetsLevina V, Su Y, Gorelik E.
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The role of the tryptophan-catabolizing enzyme, indoleamine 2,3-dioxygenase (IDO1), in tumor escape and metastasis formation was analyzed using two pairs of Ido1+ and Ido1- murine breast cancer cell lines. Ido1 expression in 4T1 cells was knocked down by shRNA, and Ido1 expression in NT-5 cells was upregulated by stable transfection. Growth of Ido1- tumors and spontaneous metastasis formation were inhibited in immunocompetent mice. A higher level of cytotoxic T lymphocytes was generated by spleen cells from mice bearing Ido1- tumors than Ido1+ tumors. Tumor and metastatic growth was enhanced in immunodeficient mice, confirming an intensified immune response in the absence of Ido1 expression. However, Ido1+ tumors grow faster than Ido1- tumors in immunodeficient SCID/beige mice (lacking T, B, and NK cells) suggesting that some Ido1-controlled nonimmunological mechanisms may be involved in tumor cell growth regulation. In vitro experiments demonstrated that downregulation of Ido1 in tumor cells was associated with decreased cell proliferation, increased apoptosis, and changed expression of cell cycle regulatory genes, whereas upregulation of Ido1 in the cells had the opposite effects. Taken together, our findings indicate that Ido1 expression could exert immunological and nonimmunological effects in murine breast tumor cells.
Also flagged:cancertranscriptional factortumorAIDcytidine deaminasenuclear factor
Journal Article2012-05-11No SnippetsShimizu T, Marusawa H, Endo Y, Chiba T.
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Chronic inflammation is a strong risk factor for the development of cancer. Many previous studies have demonstrated that a transcriptional factor, nuclear factor (NF)-κB, plays an important role in the association between inflammation and cancer development, particularly tumor promotion and tumor progression. Although it is well recognized that cancer develops via stepwise accumulation of genetic aberrations, the mechanisms underlying the generation of these genetic alterations in normal epithelial cells under inflammatory conditions are not known. We recently demonstrated that pathogenic bacterial or viral factors and the subsequent inflammatory reactions lead to the aberrant expression of a DNA mutator enzyme, activation-induced cytidine deaminase (AID), in various epithelial cells via NF-κB activation, which causes the accumulation of genetic alterations in tumor-related genes. AID activation is widely observed in gastrointestinal tissues with cancer-associated inflammation, such as chronic viral hepatitis, Helicobacter pylori-related gastritis, Barrett's esophagus and inflammatory bowel disease. Furthermore, a deficiency of endogenous AID expression reduces both accumulation of somatic mutations in tumor-related genes and tumor incidence in a mouse model of inflammation-associated cancer development. These findings strongly suggest that AID plays an integral role in inflammation-associated carcinogenesis and is therefore a potential target molecule for the prevention and treatment of cancers.
Also flagged:gene expressionbrilliant cresyl blueglucose-6-phosphate dehydrogenaseG6PDHannexin-VBCB
Journal Article2012-05-11✓ 1 SnippetJanowski D, Salilew-Wondim D, Torner H, Tesfaye D, Ghanem N, Tomek W, El-Sayed A, Schellander K, Hölker M.
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…LINGO1, ALDH1A3, PTHLH,BTN3A3, MRPS2 and PPM1K…
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The close contact and interaction between the oocyte and the follicular environment influence the establishment of oocyte developmental competence. Moreover, it is assumed that apoptosis in the follicular cells has a beneficial influence on the developmental competence of oocytes. The aim of this study was to investigate whether bovine oocytes with varied developmental competence show differences in the degree of apoptosis and gene expression pattern in their surrounding follicular cells (cumulus and granulosa cells). Oocytes and follicular cells from follicles of 3 to 5 mm in diameter were grouped as brilliant cresyl blue (BCB)+ and BCB- based on glucose-6-phosphate dehydrogenase (G6PDH) activity in the ooplasm by BCB staining. In the follicular cells initial, early and late apoptotic events were assessed by analyzing caspase-3 activity, annexin-V and TUNEL, respectively. Global gene expression was investigated in immature oocytes and corresponding follicular cells. BCB+ oocytes resulted in a higher blastocyst rate (19.3%) compared to the BCB- group (7.4%, P < 0.05). Moreover, the analysis of apoptosis showed a higher caspase-3 activity in the follicular cells and an increased degree of late apoptotic events in granulosa cells in the BCB+ compared with the BCB- group. Additionally, the global gene expression profile revealed a total of 34 and 37 differentially expressed genes between BCB+ and BCB- cumulus cells and granulosa cells, respectively, whereas 207 genes showed an altered transcript abundance between BCB+ and BCB- oocytes. Among these, EIF3F, RARRES2, RNF34, ACTA1, GSTA1, EIF3A, VIM and CS gene transcripts were most highly enriched in the BCB+ oocytes, whereas OLFM1, LINGO1, ALDH1A3, PTHLH, BTN3A3, MRPS2 and PPM1K were most significantly reduced in these cells. Therefore, the follicular cells enclosing developmentally competent oocytes show a higher level of apoptosis and a different pattern of gene expression compared to follicular cells enclosing non-competent bovine oocytes.
Also flagged:acute leukemiaacutemyeloblastic leukemiaSTILTAL1IKZF1
Journal Article2012-05-11✓ 1 SnippetYan L, Ping N, Zhu M, Sun A, Xue Y, Ruan C, Drexler HG, Macleod RA, Wu D, Chen S.
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Among 4,780 consecutive adult acute lymphoblastic/myeloblastic leukemia patients, we identified 117 (2.4%) patients with mixed-phenotype acute leukemia fulfilling WHO 2008 criteria; these were classified as: Blymphoid+ myeloid (n=64), T-lymphoid+myeloid (n=38), B+T-lymphoid (n=14) and trilineage (n=1). Of 92 patients karyotyped, 59 were abnormal and were classified as: complex (22 of 92), t(9;22)(q34;q11) (14 of 92), monosomy 7 (7 of 92), polysomy 21 (7 of 92), t(v;11q23) (4 of 92), t(10;11)(p15;q21) (3 of 92), while STIL-TAL1 fusion was detected in one (T+My) patient. After investigating common acute leukemia-related mutations in 17 genes, 12 of 31 (39%) patients were found to have at least one mutation, classified with: IKZF1 deletion (4 of 31), and EZH2 (3 of 31), ASXL1 (3 of 31), ETV6 (2 of 31), NOTCH1 (1 of 31), and TET2 (1 of 31) mutations. Array-CGH revealed genomic deletions of CDKN2A (4 of 12), IKZF1 (3 of 12), MEF2C (2 of 12), BTG1 (2 of 12), together with BCOR, EBF1, K-RAS, LEF1, MBNL1, PBX3, and RUNX1 (one of 12 each). Our results indicate that mixed-phenotype acute leukemia is a complex entity with heterogeneous clinical, immunophenotypic, cytogenetic, and molecular genetic features.
The loss of the H(2)O(2) scavenger protein encoded by Prdx1 in mice leads to an elevation of reactive oxygen species (ROS) and tumorigenesis of different tissues. Loss of heterozygosity (LOH) mutations could initiate tumorigenesis through loss of tumor suppressor gene function in heterozygous somatic cells. A connection between the severity of ROS and the frequency of LOH mutations in vivo has not been established. Therefore, in this study, we characterized in vivo LOH in ear fibroblasts and splenic T cells of 3-4 month old Prdx1 deficient mice. We found that the loss of Prdx1 significantly elevates ROS amounts in T cells and fibroblasts. The basal amounts of ROS were higher in fibroblasts than in T cells, probably due to a less robust Prdx1 peroxidase activity in the former. Using Aprt as a LOH reporter, we observed an elevation in LOH mutation frequency in fibroblasts, but not in T cells, of Prdx1(-/-) mice compared to Prdx1(+/+) mice. The majority of the LOH mutations in both cell types were derived from mitotic recombination (MR) events. Interestingly, Mlh1, which is known to suppress MR between divergent sequences, was found to be significantly down-regulated in fibroblasts of Prdx1(-/-) mice. Therefore, the combination of elevated ROS amounts and down-regulation of Mlh1 may have contributed to the elevation of MR in fibroblasts of Prdx1(-/-) mice. We conclude that each tissue may have a distinct mechanism through which Prdx1 deficiency promotes tumorigenesis.
Also flagged:morphineoxycodoneopioid addictionopioidheroinantibodies
Journal Article2012-05-11No SnippetsPravetoni M, Raleigh MD, Le Naour M, Tucker AM, Harmon TM, Jones JM, Birnbaum AK, Portoghese PS, Pentel PR.
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Opioid conjugate vaccines have shown promise in animal models as a potential treatment for opioid addiction. Individual vaccines are quite specific and each targets only a limited number of structurally similar opioids. Since opioid users can switch or transition between opioids, we studied a bivalent immunization strategy of combining 2 vaccines that could target several of the most commonly abused opioids; heroin, oxycodone and their active metabolites. Morphine (M) and oxycodone (OXY) haptens were conjugated to keyhole limpet hemocyanin (KLH) through tetraglycine (Gly)(4) linkers at the C6 position. Immunization of rats with M-KLH alone produced high titers of antibodies directed against heroin, 6-monoacetylmorphine (6-MAM) and morphine. Immunization with OXY-KLH produced high titers of antibodies against oxycodone and oxymorphone. Immunization with the bivalent vaccine produced consistently high antibody titers against both immunogens. Bivalent vaccine antibody titers against the individual immunogens were higher than with the monovalent vaccines alone owing, at least in part, to cross-reactivity of the antibodies. Administration of a single concurrent intravenous dose of 6-MAM and oxycodone to rats immunized with the bivalent vaccine increased 6-MAM, morphine and oxycodone retention in serum and reduced the distribution of 6-MAM and oxycodone to brain. Vaccine efficacy correlated with serum antibody titers for both monovalent vaccines, alone or in combination. Efficacy of the individual vaccines was not compromised by their combined use. Consistent with the enhanced titers in the bivalent group, a trend toward enhanced pharmacokinetic efficacy with the bivalent vaccine was observed. These data support the possibility of co-administering two or more opioid vaccines concurrently to target multiple abusable opioids without compromising the immunogenicity or efficacy of the individual components.
Also flagged:OAmatrix metalloproteinase-1MMP-1MMP-3MMP-13myeloperoxidase
Journal Article2012-05-11No SnippetsFernández-Moreno M, Soto-Hermida A, Oreiro N, Pértega S, Fenández-López C, Rego-Pérez I, Blanco FJ.
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<h4>Objective</h4>To assess a mitochondrion-related phenotype in patients with osteoarthritis (OA).<h4>Methods</h4>Serum levels of the following OA-related biomarkers: matrix metalloproteinase-1 (MMP-1); MMP-3; MMP-13; myeloperoxidase (MPO); a peptide of the alpha-helical region of type II collagen, Coll2-1, and its nitrated form Coll2-1NO(2); a C-terminal neoepitope generated by the collagenase-mediated cleavage of collagen type II triple helix, C2C; the C-propeptide of collagen type II, CPII; hyaluronic acid (HA); human cartilage glycoprotein 39, YKL-40; cartilage oligomeric matrix protein; and cathepsin K were analyzed in 48 OA patients and 52 healthy controls carrying the haplogroups H and J. Logistic regression models and receiver operating characteristic (ROC) curves were performed to predict the onset of OA.<h4>Results</h4>MMP-13 was the only biomarker significantly increased in OA patients compared to healthy controls in both haplogroups H and J. The collagen type II biomarkers, Coll2-1, Coll2-1NO(2), the Coll2-1NO(2)/Coll2-1 ratio, C2C, CPII, and the C2C:CPII ratio were significantly increased in OA patients carrying haplogroup H compared to OA carriers of the haplogroup J. Two logistic regression models for diagnosis were constructed and adjusted for age, gender, and body mass index. For haplogroup H, the biomarkers significantly associated with OA were MMP-13 and Coll2-1; the area under the curve (AUC) of the ROC curve for this model was 0.952 (95% CI = 0.892-1.012). For haplogroup J, the only biomarker significantly associated with OA was MMP-13; the AUC for this model was 0.895 (95% CI = 0.801-0.989).<h4>Conclusion</h4>The mitochondrial DNA haplogroups are potential complementary candidates for biomarkers of OA; their genotyping in conjunction with the assessment of classical protein molecular markers is recommended.
Also flagged:fertilizationLdhbUchl1AlbHsp90aa1Prss1
Journal Article2012-05-10✓ 2 SnippetsPeng Q, Yang H, Xue S, Shi L, Yu Q, Kuang Y.
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Abstract)
…Ldhb, PADi6, Uchl1,Pebp1, Alb, Hsp90aa1, Prss1,…
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<h4>Objective</h4>Mammalian oocytes undergo a cortical reaction after fertilization, releasing cortical granules and other proteins into the perivitelline space and inhibiting polyspermy. Few studies have evaluated the biological functions and properties of these proteins.<h4>Study design</h4>We investigated mouse oocytes in which the zona pellucida (ZP) was present (ZP-intact group) or absent (ZP-free group).<h4>Results</h4>After being activated by Srcl2, secreted proteins are collected from mouse oocytes. Mass spectrometry analysis was performed that identified proteins such as Ldhb, PADi6, Uchl1, Pebp1, Alb, Hsp90aa1, Prss1, trypsinogen 7, trypsin 4, trypsin 10, Sod1, Zp1, Zp2, Zp3, Akap8, Npm2, Pkm2 and Ppia in the ZP-free group. Proteins such as Ldhb, Uchl1, Prss1, trypsin 10, trypsinogen 7, and Ast1 were identified in the ZP-intact groups. The expression of some proteins, including Ldhb, Alb and Sod1, were initially detected following oocyte activation. The finding of four trypsin subtypes, such as Prss1, further support previous observations. Studies investigating the physiological functions and properties of these proteins are ongoing.<h4>Conclusions</h4>Research on these cortical proteins provides a theoretical basis for understanding polyspermy inhibition at the level of ZP and gives technological support for fertilization detection, assessment of oocyte quality and embryonic culture.
Also flagged:Silver nanoparticleswaterlymphomagene expressionTkchromosome
Journal Article2012-05-10No SnippetsMei N, Zhang Y, Chen Y, Guo X, Ding W, Ali SF, Biris AS, Rice P, Moore MM, Chen T.
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Silver nanoparticles (Ag-NPs) have increasingly been used for coatings on various textiles and certain implants, for the treatment of wounds and burns, as a water disinfectant, and in air-freshener sprays. The wide use of Ag-NPs may have potential human health impacts. In this study, the mutagenicity of 5-nm Ag-NPs was evaluated in the mouse lymphoma assay system, and modes of action were assessed using standard alkaline and enzyme-modified Comet assays and gene expression analysis. Treatments of L5178Y/Tk(+/-) mouse lymphoma cells with 5-nm uncoated Ag-NPs resulted in a significant yield of mutants at doses between 3 and 6 μg/mL; the upper range was limited by toxicity. Loss of heterozygosity analysis of the Tk mutants revealed that treatments with uncoated Ag-NPs induced mainly chromosomal alterations spanning less than 34 megabase pairs on chromosome 11. Although no significant induction of DNA damage in Ag-NP-treated mouse lymphoma cells was observed in the standard Comet assay, the Ag-NP treatments induced a dose-responsive increase in oxidative DNA damage in the enzyme-modified Comet assay in which oxidative lesion-specific endonucleases were added. Gene expression analysis using an oxidative stress and antioxidant defense polymerase chain reaction (PCR) array showed that the expressions of 17 of the 59 genes on the arrays were altered in the cells treated with Ag-NPs. These genes are involved in production of reactive oxygen species, oxidative stress response, antioxidants, oxygen transporters, and DNA repair. These results suggest that 5 nm Ag-NPs are mutagenic in mouse lymphoma cells due to induction of oxidative stress by the Ag-NPs.
Also flagged:Dithiolperoxiredoxin 1oxygenagingneurodegenerative disordersHuntington disease
Journal Article2012-05-10✓ 5 SnippetsPitts A, Dailey K, Newington JT, Chien A, Arseneault R, Cann T, Thompson LM, Cumming RC.
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…of the Huntingtin (Htt) protein with either…
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…hogenic polyglutamine repeat (Htt-103Q) were resolved by…
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…response to mutantHttexpressed in either…
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…cells attenuated mutantHtt-induced toxicity.…
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…also prevented mutantHtt-induced loss of Prx1…
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Mitochondrial dysfunction and elevated reactive oxygen species are strongly implicated in both aging and various neurodegenerative disorders, including Huntington disease (HD). Because reactive oxygen species can promote the selective oxidation of protein cysteine sulfhydryl groups to disulfide bonds we examined the spectrum of disulfide-bonded proteins that were specifically altered in a HD context. Protein extracts from PC12 cells overexpressing the amino-terminal fragment of the Huntingtin (Htt) protein with either a nonpathogenic or pathogenic polyglutamine repeat (Htt-103Q) were resolved by redox two-dimensional PAGE followed by mass spectrometry analysis. Several antioxidant proteins were identified that exhibited changes in disulfide bonding unique to Htt-103Q expressing cells. In particular, the antioxidant protein peroxiredoxin 1 (Prx1) exhibited both decreased expression and hyperoxidation in response to mutant Htt expressed in either PC12 cells or immortalized striatal cells exposed to 3-nitropropionic acid. Ectopic expression of Prx1 in PC12 cells attenuated mutant Htt-induced toxicity. In contrast, short hairpin RNA-mediated knockdown of Prx1 potentiated mHtt toxicity. Furthermore, treatment with the dithiol-based compounds dimercaptopropanol and dimercaptosuccinic acid suppressed toxicity in both HD cell models, whereas monothiol compounds were relatively ineffective. Dimercaptopropanol treatment also prevented mutant Htt-induced loss of Prx1 expression in both cell models. Our studies reveal for the first time that pathogenic Htt can affect the expression and redox state of antioxidant proteins; an event countered by specific dithiol-based compounds. These findings should provide a catalyst to explore the use of dithiol-based drugs for the treatment of neurodegenerative diseases.
The objective of this study was to determine if there are common innate differences in gene expression or gene pathways in the ventral tegmental area (VTA) among 5 different pairs of rat lines selectively bred for high (HEC) or low (LEC) ethanol consumption: (a) alcohol-preferring (P) vs. alcohol-non-preferring (NP) rats; (b) high-alcohol-drinking (HAD) vs. low-alcohol-drinking (LAD) rats (replicate line pairs 1 and 2); (c) ALKO alcohol (AA) vs. nonalcohol (ANA) rats; and (d) Sardinian alcohol-preferring (sP) vs. alcohol-nonpreferring (sNP) rats. Microarray analysis revealed between 370 and 1340 unique named genes that significantly differed in expression between the individual line-pairs. Analysis using Gene Ontology (GO) and Ingenuity Pathways information indicated significant categories and networks in common for up to 3 line-pairs, but not for all 5 line-pairs; moreover, there were few genes in common in these categories and networks. ANOVA of the combined data for the 5 line-pairs indicated 1295 significant (p<0.01) differences in expression of named genes. Although no individual named gene was significant across all 5 line-pairs, there were 22 genes that overlapped in the same direction in 3 or 4 of the line-pairs. Overall, the findings suggest that (a) some biological categories or networks may be in common for subsets of line-pairs; and (b) regulation of different genes and/or combinations of multiple biological systems (e.g., transcription, synaptic function, intracellular signaling and protection against oxidative stress) within the VTA (possibly involving dopamine and glutamate) may be contributing to the disparate alcohol drinking behaviors of these line-pairs.
Also flagged:memoryCD27MMCBcl6Epstein-Barr virus infectioncell-growth
Journal Article2012-05-10No SnippetsHeath E, Begue-Pastor N, Chaganti S, Croom-Carter D, Shannon-Lowe C, Kube D, Feederle R, Delecluse HJ, Rickinson AB, Bell AI.
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Epstein-Barr virus (EBV), a lymphomagenic human herpesvirus, colonises the host through polyclonal B cell-growth-transforming infections yet establishes persistence only in IgD⁺ CD27⁺ non-switched memory (NSM) and IgD⁻ CD27⁺ switched memory (SM) B cells, not in IgD⁺ CD27⁻ naïve (N) cells. How this selectivity is achieved remains poorly understood. Here we show that purified N, NSM and SM cell preparations are equally transformable in vitro to lymphoblastoid cells lines (LCLs) that, despite upregulating the activation-induced cytidine deaminase (AID) enzyme necessary for Ig isotype switching and Ig gene hypermutation, still retain the surface Ig phenotype of their parental cells. However, both N- and NSM-derived lines remain inducible to Ig isotype switching by surrogate T cell signals. More importantly, IgH gene analysis of N cell infections revealed two features quite distinct from parallel mitogen-activated cultures. Firstly, following 4 weeks of EBV-driven polyclonal proliferation, individual clonotypes then become increasingly dominant; secondly, in around 35% cases these clonotypes carry Ig gene mutations which both resemble AID products and, when analysed in prospectively-harvested cultures, appear to have arisen by sequence diversification in vitro. Thus EBV infection per se can drive at least some naïve B cells to acquire Ig memory genotypes; furthermore, such cells are often favoured during an LCL's evolution to monoclonality. Extrapolating to viral infections in vivo, these findings could help to explain how EBV-infected cells become restricted to memory B cell subsets and why EBV-driven lymphoproliferative lesions, in primary infection and/or immunocompromised settings, so frequently involve clones with memory genotypes.
The pairing of homologous chromosomes is a fundamental feature of the meiotic cell. In addition, a number of species exhibit homolog pairing in nonmeiotic, somatic cells as well, with evidence for its impact on both gene regulation and double-strand break (DSB) repair. An extreme example of somatic pairing can be observed in Drosophila melanogaster, where homologous chromosomes remain aligned throughout most of development. However, our understanding of the mechanism of somatic homolog pairing remains unclear, as only a few genes have been implicated in this process. In this study, we introduce a novel high-throughput fluorescent in situ hybridization (FISH) technology that enabled us to conduct a genome-wide RNAi screen for factors involved in the robust somatic pairing observed in Drosophila. We identified both candidate "pairing promoting genes" and candidate "anti-pairing genes," providing evidence that pairing is a dynamic process that can be both enhanced and antagonized. Many of the genes found to be important for promoting pairing are highly enriched for functions associated with mitotic cell division, suggesting a genetic framework for a long-standing link between chromosome dynamics during mitosis and nuclear organization during interphase. In contrast, several of the candidate anti-pairing genes have known interphase functions associated with S-phase progression, DNA replication, and chromatin compaction, including several components of the condensin II complex. In combination with a variety of secondary assays, these results provide insights into the mechanism and dynamics of somatic pairing.
Also flagged:chromatinLinker histone H1embryogenesisleukemia inhibitory factorgene expressionmethylation
Journal Article2012-05-10✓ 1 SnippetZhang Y, Cooke M, Panjwani S, Cao K, Krauth B, Ho PY, Medrzycki M, Berhe DT, Pan C, McDevitt TC, Fan Y.
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…levels of H1linker histoneshistones and chromatin…
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Pluripotent embryonic stem cells (ESCs) are known to possess a relatively open chromatin structure; yet, despite efforts to characterize the chromatin signatures of ESCs, the role of chromatin compaction in stem cell fate and function remains elusive. Linker histone H1 is important for higher-order chromatin folding and is essential for mammalian embryogenesis. To investigate the role of H1 and chromatin compaction in stem cell pluripotency and differentiation, we examine the differentiation of embryonic stem cells that are depleted of multiple H1 subtypes. H1c/H1d/H1e triple null ESCs are more resistant to spontaneous differentiation in adherent monolayer culture upon removal of leukemia inhibitory factor. Similarly, the majority of the triple-H1 null embryoid bodies (EBs) lack morphological structures representing the three germ layers and retain gene expression signatures characteristic of undifferentiated ESCs. Furthermore, upon neural differentiation of EBs, triple-H1 null cell cultures are deficient in neurite outgrowth and lack efficient activation of neural markers. Finally, we discover that triple-H1 null embryos and EBs fail to fully repress the expression of the pluripotency genes in comparison with wild-type controls and that H1 depletion impairs DNA methylation and changes of histone marks at promoter regions necessary for efficiently silencing pluripotency gene Oct4 during stem cell differentiation and embryogenesis. In summary, we demonstrate that H1 plays a critical role in pluripotent stem cell differentiation, and our results suggest that H1 and chromatin compaction may mediate pluripotent stem cell differentiation through epigenetic repression of the pluripotency genes.
Also flagged:obesityLYPLAL1SATFTOTHNSL2central obesity
Journal Article2012-05-10✓ 1 SnippetFox CS, Liu Y, White CC, Feitosa M, Smith AV, Heard-Costa N, Lohman K, GIANT Consortium, MAGIC Consortium, GLGC Consortium, Johnson AD, Foster MC, Greenawalt DM, Griffin P, Ding J, Newman AB, Tylavsky F, Miljkovic I, Kritchevsky SB, Launer L, Garcia M, Eiriksdottir G, Carr JJ, Gudnason V, Harris TB, Cupples LA, Borecki IB.
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…VAT/SAT ratio atNEGR1.…
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Body fat distribution, particularly centralized obesity, is associated with metabolic risk above and beyond total adiposity. We performed genome-wide association of abdominal adipose depots quantified using computed tomography (CT) to uncover novel loci for body fat distribution among participants of European ancestry. Subcutaneous and visceral fat were quantified in 5,560 women and 4,997 men from 4 population-based studies. Genome-wide genotyping was performed using standard arrays and imputed to ~2.5 million Hapmap SNPs. Each study performed a genome-wide association analysis of subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), VAT adjusted for body mass index, and VAT/SAT ratio (a metric of the propensity to store fat viscerally as compared to subcutaneously) in the overall sample and in women and men separately. A weighted z-score meta-analysis was conducted. For the VAT/SAT ratio, our most significant p-value was rs11118316 at LYPLAL1 gene (p = 3.1 × 10E-09), previously identified in association with waist-hip ratio. For SAT, the most significant SNP was in the FTO gene (p = 5.9 × 10E-08). Given the known gender differences in body fat distribution, we performed sex-specific analyses. Our most significant finding was for VAT in women, rs1659258 near THNSL2 (p = 1.6 × 10-08), but not men (p = 0.75). Validation of this SNP in the GIANT consortium data demonstrated a similar sex-specific pattern, with observed significance in women (p = 0.006) but not men (p = 0.24) for BMI and waist circumference (p = 0.04 [women], p = 0.49 [men]). Finally, we interrogated our data for the 14 recently published loci for body fat distribution (measured by waist-hip ratio adjusted for BMI); associations were observed at 7 of these loci. In contrast, we observed associations at only 7/32 loci previously identified in association with BMI; the majority of overlap was observed with SAT. Genome-wide association for visceral and subcutaneous fat revealed a SNP for VAT in women. More refined phenotypes for body composition and fat distribution can detect new loci not previously uncovered in large-scale GWAS of anthropometric traits.
Also flagged:serotonin transportercognitionpsychopathologyserotonindepressionanxiety disorders
Journal Article2012-05-10No SnippetsJasinska AJ, Ho SS, Taylor SF, Burmeister M, Villafuerte S, Polk TA.
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Emotion-cognition interactions are critical in goal-directed behavior and may be disrupted in psychopathology. Growing evidence also suggests that emotion-cognition interactions are modulated by genetic variation, including genetic variation in the serotonin system. The goal of the current study was to examine the impact of threat-related distracters and serotonin transporter promoter polymorphism (5-HTTLPR/rs25531) on cognitive task performance in healthy females. Using a novel threat-distracter version of the Multi-Source Interference Task specifically designed to probe emotion-cognition interactions, we demonstrate a robust and temporally dynamic modulation of cognitive interference effects by threat-related distracters relative to other distracter types and relative to no-distracter condition. We further show that threat-related distracters have dissociable and opposite effects on cognitive task performance in easy and difficult task conditions, operationalized as the level of response interference that has to be surmounted to produce a correct response. Finally, we present evidence that the 5-HTTLPR/rs25531 genotype in females modulates susceptibility to cognitive interference in a global fashion, across all distracter conditions, and irrespective of the emotional salience of distracters, rather than specifically in the presence of threat-related distracters. Taken together, these results add to our understanding of the processes through which threat-related distracters affect cognitive processing, and have implications for our understanding of disorders in which threat signals have a detrimental effect on cognition, including depression and anxiety disorders.
<h4>Background</h4>Hepatic cirrhosis is a common pathway of progressive liver destruction from multiple causes. Iron uptake can occur within the hepatic parenchyma or within the various nodules that form in a cirrhotic liver, termed siderotic nodules. Siderotic nodule formation has been shown to correlate with inflammatory activity, and while the relationship between siderotic nodule formation and malignancy remains unclear, iron distribution within hepatic nodules has known implications for the detection of hepatocellular carcinoma. We aimed to evaluate the role of abdominal susceptibility-weighted imaging in the detection of siderotic nodules in cirrhotic patients.<h4>Methodology/principal findings</h4>Forty-six (46) cirrhotic patients with at least one siderotic nodule detected on previous imaging underwent both computed tomography and magnetic resonance imaging (T1-, T2-, T2*-, and susceptibility-weighted imaging) at 3.0 Tesla. Imaging data was independently analyzed by two radiologists. Siderotic nodule count was determined for each modality and imaging sequence. For each magnetic resonance imaging technique, siderotic nodule conspicuity was assessed on a 3 point scale (1 = weak, 2 = moderate, 3 = strong). More nodules were detected by susceptibility weighted imaging (n = 2935) than any other technique, and significantly more than by T2* weighted imaging (n = 1696, p<0.0001). Lesion conspicuity was also highest with susceptibility-weighted imaging, with all nodules found to be moderate (n = 6) or strong (n = 40); a statistically significant difference (p<0.001).<h4>Conclusions</h4>Susceptibility-weighted imaging had the greatest lesion conspicuity and detected the highest number of siderotic nodules suggesting it is the most sensitive imaging technique to detect siderotic nodules in cirrhotic patients.
Also flagged:Myo10Myosin Xaxonantibodycytochalasin Denhanced green fluorescence protein
Journal Article2012-05-10✓ 1 SnippetYu H, Wang N, Ju X, Yang Y, Sun D, Lai M, Cui L, Sheikh MA, Zhang J, Wang X, Zhu X.
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…β-integrin [22] ,DCC[23] , ALK6…
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Myosin X (Myo10) with pleckstrin homology (PH) domains is a motor protein acting in filopodium initiation and extension. However, its potential role has not been fully understood, especially in neuronal development. In the present study the preferential accumulation of Myo10 in axon tips has been revealed in primary culture of hippocampal neurons with the aid of immunofluorescence from anti-Myo10 antibody in combination with anti-Tuj1 antibody as specific marker. Knocking down Myo10 gene transcription impaired outgrowth of axon with loss of Tau-1-positive phenotype. Interestingly, inhibition of actin polymerization by cytochalasin D rescued the defect of axon outgrowth. Furthermore, ectopic expression of Myo10 with enhanced green fluorescence protein (EGFP) labeled Myo10 mutants induced multiple axon-like neurites in a motor-independent way. Mechanism studies demonstrated that the recruitment of Myo10 through its PH domain to phosphatidylinositol (3,4,5)-trisphosphate (PtdIns (3,4,5) P3) was essential for axon formation. In addition, in vivo studies confirmed that Myo10 was required for neuronal morphological transition during radial neuronal migration in the developmental neocortex.
Also flagged:systemic lupus erythematosusSLEautoimmune disorderCytokinesBLKFC
Journal Article2012-05-10✓ 2 SnippetsConnolly JJ, Hakonarson H.
In-Text Gene Mentions
S I O 001029)
…A recent study by Sanchez et al. [42] which targeted this and 15 other SLE-associated loci found that SLE renal disorder was significantly correlated with risk alleles in ITGAM and TNFSF4. Similar associations were found for ITGAM-discoid rash, STAT4-protection from oral ulcers, and IL21- hematological disorder and suggest ways in which genetic profiling may be used to predict SLE etiology.…
S I O 001029)
…Although a number of GWAS have not found a significant association with this locus, a large study of 1,724 SLE patients and 2,024 healthy controls of African American descent did replicate BANK1 as an SLE candidate in this cohort (as well as C8orf13-BLK, TNFSF4, KIAA1542, and CTLA4) [98].…
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Systemic lupus erythematosus (SLE) is a complex autoimmune disorder, known to have a strong genetic component. Concordance between monozygotic twins is approximately 30-40%, which is 8-20 times higher than that of dizygotic twins. In the last decade, genome-wide approaches to understanding SLE have yielded many candidate genes, which are important to understanding the pathophysiology of the disease and potential targets for pharmaceutical intervention. In this paper, we focus on the role of cytokines and examine how genome-wide association studies, copy number variation studies, and next-generation sequencing are being employed to understand the etiology of SLE. Prominent genes identified by these approaches include BLK, FCγR3B, and TREX1. Our goal is to present a brief overview of genomic approaches to SLE and to introduce some of the key discussion points pertinent to the field.
Also flagged:cytokinedeathinsulinsecretiondiabetestumor
Journal Article2012-05-10No SnippetsBravo-Egana V, Rosero S, Klein D, Jiang Z, Vargas N, Tsinoremas N, Doni M, Podetta M, Ricordi C, Molano RD, Pileggi A, Pastori RL.
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Nonspecific inflammation in the transplant microenvironment results in β-cell dysfunction and death influencing negatively graft outcome. MicroRNA (miRNA) expression and gene target regulation in transplanted islets are not yet well characterized. We evaluated the impact of inflammation on miRNA expression in transplanted rat islets. Islets exposed in vitro to proinflammatory cytokines and explanted syngeneic islet grafts were evaluated by miRNA arrays. A subset of 26 islet miRNAs was affected by inflammation both in vivo and in vitro. Induction of miRNAs was dependent on NF-κB, a pathway linked with cytokine-mediated islet cell death. RT-PCR confirmed expression of 8 miRNAs. The association between these miRNAs and mRNA target-predicting algorithms in genome-wide RNA studies of β-cell inflammation identified 238 potential miRNA gene targets. Several genes were ontologically associated with regulation of insulin signaling and secretion, diabetes, and islet physiology. One of the most activated miRNAs was miR-21. Overexpression of miR-21 in insulin-secreting MIN6 cells downregulated endogenous expression of the tumor suppressor Pdcd4 and of Pclo, a Ca(2+) sensor protein involved in insulin secretion. Bioinformatics identified both as potential targets. The integrated analysis of miRNA and mRNA expression profiles revealed potential targets that may identify molecular targets for therapeutic interventions.
Also flagged:Polycystin-1amphiregulinCREBAP1autosomal dominant polycystic kidney diseaseADPKD
Journal Article2012-05-09No SnippetsAguiari G, Bizzarri F, Bonon A, Mangolini A, Magri E, Pedriali M, Querzoli P, Somlo S, Harris PC, Catizone L, Del Senno L.
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In autosomal dominant polycystic kidney disease (ADPKD), renal cyst development and enlargement, as well as cell growth, are associated with alterations in several pathways, including cAMP and activator protein 1 (AP1) signalling. However, the precise mechanism by which these molecules stimulate cell proliferation is not yet fully understood. We now show by microarray analysis, luciferase assay, mutagenesis, and chromatin immunoprecipitation that CREB and AP1 contribute to increased expression of the amphiregulin gene, which codifies for an epidermal growth factor-like peptide, in ADPKD cystic cells, thereby promoting their cell growth. Increased amphiregulin (AR) expression was associated with abnormal cell proliferation in both PKD1-depleted and -mutated epithelial cells, as well as primary cystic cell lines isolated from ADPKD kidney tissues. Consistently, normal AR expression and proliferation were re-established in cystic cells by the expression of a mouse full-length PC1. Finally, we show that anti-AR antibodies and inhibitors of AP1 are able to reduce cell proliferation in cystic cells by reducing AR expression and EGFR activity. AR can therefore be considered as one of the key activators of the growth of human ADPKD cystic cells and thus a new potential therapeutic target.
Also flagged:activating transcription factor-4serotonin transporterSerotonin(5-HT) transporterextracellularsynapse
Journal Article2012-05-09✓ 5 SnippetsUshijima K, Koyanagi S, Sato Y, Ogata T, Matsunaga N, Fujimura A, Ohdo S.
In-Text Gene Mentions
Abstract)
…These results indicated that the circuit of circadian-basis molecular regulation between the clockwork system and mouse 5-HTT gene was connected by the ATF4 signaling pathway.…
Abstract)
…In addition, mutation of the Clock gene disrupted temporal binding of ATF4 to the CRE site in the 5-HTT promoter.…
Abstract)
…ATF4 significantly activated 5-HTT transcription in vitro and time dependently bound to the CRE site in the 5-HTT promoter in the mouse midbrain.…
Abstract)
…Serotonin (5-HT) transporter (5-HTT) plays a key…
Serotonin (5-HT) transporter (5-HTT) plays a key role in the control of 5-HT neuronal activity by reuptaking extracellular 5-HT from the synapse cleft. We have previously demonstrated that 5-HTT mRNA expression levels and its uptake activity in the mouse midbrain are significantly higher in the dark phase than those in the light phase. However, the molecular mechanisms of time-dependent expression of 5-HTT have not been clarified. In this study, expression of 5-HTT mRNA in the mouse midbrain showed a significant 24-h rhythm and was higher in the dark phase. Although such an oscillation was eliminated by a Clock gene mutation, CLOCK and BMAL1 did not activate 5-HTT transcription in the luciferase reporter assay. Activating transcription factor-4 (ATF4), a member of the ATF/cAMP response element (CRE)-binding protein family, is a component responsible for sustaining circadian oscillations of CRE-mediated gene expression. ATF4 significantly activated 5-HTT transcription in vitro and time dependently bound to the CRE site in the 5-HTT promoter in the mouse midbrain. In addition, mutation of the Clock gene disrupted temporal binding of ATF4 to the CRE site in the 5-HTT promoter. These results indicated that the circuit of circadian-basis molecular regulation between the clockwork system and mouse 5-HTT gene was connected by the ATF4 signaling pathway.
Also flagged:glutaminespolyprolineprionPSIPINneurodegenerative diseases
Journal Article2012-05-09✓ 5 SnippetsZhao X, Park YN, Todor H, Moomau C, Masison D, Eisenberg E, Greene LE.
In-Text Gene Mentions
Introduction)
…Furthermore, even when Htt fragments with expanded polyQ repeat regions form multiple aggregates, whether the fragment is toxic depends on the amino acids flanking the polyQ repeat region (14).…
Results)
…The effect of expressing these Htt fragments was examined using a spot assay in which the yeast were serially diluted on selection plates containing galactose to induce expression of the Htt fragments (Fig. 2A).…
S I O 001029)
…Yeast were incubated in galactose for 26 h to express Htt fragments.…
Results)
…After overnight induction of Htt with galactose medium, the [PSI+]/Δrnq1 yeast were imaged by confocal microscopy.…
Introduction)
…Studies extending the Huntington disease model to yeast showed that the formation of Htt aggregates is dependent on the length of the polyQ repeat region in the expressed fragments, just as was observed in mammalian cells (10).…
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Expression of huntingtin fragments with 103 glutamines (HttQ103) is toxic in yeast containing either the [PIN(+)] prion, which is the amyloid form of Rnq1, or [PSI(+)] prion, which is the amyloid form of Sup35. We find that HttQP103, which has a polyproline region at the C-terminal end of the polyQ repeat region, is significantly more toxic in [PSI(+)] yeast than in [PIN(+)], even though HttQP103 formed multiple aggregates in both [PSI(+)] and [PIN(+)] yeast. This toxicity was only observed in the strong [PSI(+)] variant, not the weak [PSI(+)] variant, which has more soluble Sup35 present than the strong variant. Furthermore, expression of the MC domains of Sup35, which retains the C-terminal domain of Sup35, but lacks the N-terminal prion domain, almost completely rescued HttQP103 toxicity, but was less effective in rescuing HttQ103 toxicity. Therefore, the toxicity of HttQP103 in yeast containing the [PSI(+)] prion is primarily due to sequestration of the essential protein, Sup35.
Also flagged:tamoxifentype I insulin-like growth factor receptorinsulin-like growth factorIGFbreast cancerIGF1R
Journal Article2012-05-09No SnippetsFagan DH, Uselman RR, Sachdev D, Yee D.
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The role of the insulin-like growth factor (IGF) system in breast cancer is well defined, and inhibitors of this pathway are currently in clinical trials. The majority of anti-IGF1R clinical trials are in estrogen receptor-positive patients who have progressed on prior endocrine therapy; early reports show no benefit for addition of IGF1R inhibitors to endocrine therapy in this setting. In this study, we examined the effectiveness of IGF1R inhibitors in vitro by generating tamoxifen-resistant (TamR) cells. We found that TamR cells had diminished levels of IGF1R with unchanged levels of insulin receptor (IR), and failed to respond to IGF-I-induced Akt activation, proliferation, and anchorage-independent growth while retaining responsiveness to both insulin and IGF-II. The IGF1R antibody dalotuzumab inhibited IGF-I-mediated Akt phosphorylation, proliferation, and anchorage-independent growth in parental cells, but had no effect on TamR cells. An IGF1R tyrosine kinase inhibitor, AEW541, with equal potency for the IGF1R and IR, inhibited IGF-I-, IGF-II-, and insulin-stimulated Akt phosphorylation, proliferation, and anchorage-independent growth in parental cells. Interestingly, AEW541 also inhibited insulin- and IGF-II-stimulated effects in TamR cells. Tamoxifen-treated xenografts also had reduced levels of IGF1R, and dalotuzumab did not enhance the effect of tamoxifen. We conclude that cells selected for tamoxifen resistance in vitro have downregulated IGF1R making antibodies directed against this receptor ineffective. Inhibition of IR may be necessary to manage tamoxifen-resistant breast cancer.
Also flagged:Gametogenesisreproductiongene expressionmitosischromatinbindin
Journal Article2012-05-09✓ 1 SnippetDheilly NM, Lelong C, Huvet A, Kellner K, Dubos MP, Riviere G, Boudry P, Favrel P.
In-Text Gene Mentions
Discussion)
…of meiosis I;Condensin-2, expressed in oocytes,…
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<h4>Background</h4>The Pacific oyster Crassostrea gigas (Mollusca, Lophotrochozoa) is an alternative and irregular protandrous hermaphrodite: most individuals mature first as males and then change sex several times. Little is known about genetic and phenotypic basis of sex differentiation in oysters, and little more about the molecular pathways regulating reproduction. We have recently developed and validated a microarray containing 31,918 oligomers (Dheilly et al., 2011) representing the oyster transcriptome. The application of this microarray to the study of mollusk gametogenesis should provide a better understanding of the key factors involved in sex differentiation and the regulation of oyster reproduction.<h4>Methodology/principal findings</h4>Gene expression was studied in gonads of oysters cultured over a yearly reproductive cycle. Principal component analysis and hierarchical clustering showed a significant divergence in gene expression patterns of males and females coinciding with the start of gonial mitosis. ANOVA analysis of the data revealed 2,482 genes differentially expressed during the course of males and/or females gametogenesis. The expression of 434 genes could be localized in either germ cells or somatic cells of the gonad by comparing the transcriptome of female gonads to the transcriptome of stripped oocytes and somatic tissues. Analysis of the annotated genes revealed conserved molecular mechanisms between mollusks and mammals: genes involved in chromatin condensation, DNA replication and repair, mitosis and meiosis regulation, transcription, translation and apoptosis were expressed in both male and female gonads. Most interestingly, early expressed male-specific genes included bindin and a dpy-30 homolog and female-specific genes included foxL2, nanos homolog 3, a pancreatic lipase related protein, cd63 and vitellogenin. Further functional analyses are now required in order to investigate their role in sex differentiation in oysters.<h4>Conclusions/significance</h4>This study allowed us to identify potential markers of early sex differentiation in the oyster C. gigas, an alternative hermaphrodite mollusk. We also provided new highly valuable information on genes specifically expressed by mature spermatozoids and mature oocytes.
Beta thalassemia major is an inherited disease resulting from reduction or total lack of beta globin chains. Patients with this disease need repeated blood transfusion for survival. This may cause oxidative stress and tissue injury due to iron overload, altered antioxidant enzymes, and other essential trace element levels. The aim of this review is to scrutinize the relationship between oxidative stress and serum trace elements, degree of damage caused by oxidative stress, and the role of antioxidant enzymes in beta thalassemia major patients. The findings indicate that oxidative stress in patients with beta thalassemia major is mainly caused by tissue injury due to over production of free radical by secondary iron overload, alteration in serum trace elements and antioxidant enzymes level. The role of trace elements like selenium, copper, iron, and zinc in beta thalassemia major patients reveals a significant change of these trace elements. Studies published on the status of antioxidant enzymes like catalase, superoxide dismutase, glutathione, and glutathione S-transferase in beta thalassemia patients also showed variable results. The administration of selective antioxidants along with essential trace elements and minerals to reduce the extent of oxidative damage and related complications in beta thalassemia major still need further evaluation.
Pluripotent cellular models have shown great promise in the study of a number of neurological disorders. Several advantages of using a stem cell model include the potential for cells to derive disease relevant neuronal cell types, providing a system for researchers to monitor disease progression during neurogenesis, along with serving as a platform for drug discovery. A number of stem cell derived models have been employed to establish in vitro research models of Huntington's disease that can be used to investigate cellular pathology and screen for drug and cell-based therapies. Although some progress has been made, there are a number of challenges and limitations that must be overcome before the true potential of this research strategy is achieved. In this article we review current stem cell models that have been reported, as well as discuss the issues that impair these studies. We also highlight the prospective application of Huntington's disease stem cell models in the development of novel therapeutic strategies and advancement of personalized medicine.
Also flagged:methylationnodegastric cancerssodiumrestriction enzymehypermethylation
Journal Article2012-05-09No SnippetsShigematsu Y, Niwa T, Yamashita S, Taniguchi H, Kushima R, Katai H, Ito S, Tsukamoto T, Ichinose M, Ushijima T.
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The accurate detection of the presence of lymph node metastases (LNM) of gastric cancers (GCs) is useful for the implementation of necessary and sufficient treatment, but current methods of detection are unsatisfactory. In the present study, we focused on DNA methylation markers since they have several advantages, including biological and chemical stability and informativeness even in the presence of contaminating cells. Using three metastatic lymph nodes and three primary GCs without LNM, methylation bead array analyses were performed, which enabled the interrogation of 485,577 CpG sites. A total of 31 CpG sites that were hypermethylated in the metastatic lymph nodes, compared with the GCs without LNM, were isolated. Using primary GCs with and without LNM (28 GCs with LNM and 10 without), their methylation levels were measured using quantitative PCR following treatment with sodium bisulfite or a methylation-sensitive restriction enzyme. Of the genomic regions around the 31 CpG sites, 10 regions demonstrated higher methylation levels in the GCs with LNM compared with the GCs without LNM (P<0.05). Finally, the hypermethylation of the 10 regions was validated using another set of samples (129 GCs with LNM and 20 without). Hypermethylation of the region around the cg06436185 CpG site predicted the presence of LNM at a sensitivity of 43% and specificity of 85%. Additionally, the hypermethylation of the region was associated with a poor survival rate among GC patients with LNM. The results of the present study indicated that the methylation status of the region was a promising candidate marker to detect the presence of LNM of GCs and may reflect the malignant potential of GCs.
Also flagged:Colorectal cancertumouroncogenescancerepithelial-mesenchymal transitionmetastatic colorectal carcinoma
Journal Article2012-05-09No SnippetsKanthan R, Senger JL, Kanthan SC.
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Colorectal cancer (CRC) is a heterogeneous disease, developing through a multipathway sequence of events guided by clonal selections. Pathways included in the development of CRC may be broadly categorized into (a) genomic instability, including chromosomal instability (CIN), microsatellite instability (MSI), and CpG island methylator phenotype (CIMP), (b) genomic mutations including suppression of tumour suppressor genes and activation of tumour oncogenes, (c) microRNA, and (d) epigenetic changes. As cancer becomes more advanced, invasion and metastases are facilitated through the epithelial-mesenchymal transition (EMT), with additional genetic alterations. Despite ongoing identification of genetic and epigenetic markers and the understanding of alternative pathways involved in the development and progression of this disease, CRC remains the second highest cause of malignancy-related mortality in Canada. The molecular events that underlie the tumorigenesis of primary and metastatic colorectal carcinoma are detailed in this manuscript.
Also flagged:dobutamineCalciumZ disktitincytoskeletonpurine-rich element binding protein B
Journal Article2012-05-08No SnippetsGurha P, Abreu-Goodger C, Wang T, Ramirez MO, Drumond AL, van Dongen S, Chen Y, Bartonicek N, Enright AJ, Lee B, Kelm RJ, Reddy AK, Taffet GE, Bradley A, Wehrens XH, Entman ML, Rodriguez A.
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<h4>Background</h4>Delineating the role of microRNAs (miRNAs) in the posttranscriptional gene regulation offers new insights into how the heart adapts to pathological stress. We developed a knockout of miR-22 in mice and investigated its function in the heart.<h4>Methods and results</h4>Here, we show that miR-22-deficient mice are impaired in inotropic and lusitropic response to acute stress by dobutamine. Furthermore, the absence of miR-22 sensitized mice to cardiac decompensation and left ventricular dilation after long-term stimulation by pressure overload. Calcium transient analysis revealed reduced sarcoplasmic reticulum Ca(2+) load in association with repressed sarcoplasmic reticulum Ca(2+) ATPase activity in mutant myocytes. Genetic ablation of miR-22 also led to a decrease in cardiac expression levels for Serca2a and muscle-restricted genes encoding proteins in the vicinity of the cardiac Z disk/titin cytoskeleton. These phenotypes were attributed in part to inappropriate repression of serum response factor activity in stressed hearts. Global analysis revealed increased expression of the transcriptional/translational repressor purine-rich element binding protein B, a highly conserved miR-22 target implicated in the negative control of muscle expression.<h4>Conclusion</h4>These data indicate that miR-22 functions as an integrator of Ca(2+) homeostasis and myofibrillar protein content during stress in the heart and shed light on the mechanisms that enhance propensity toward heart failure.
Also flagged:ADPRHL2ANKRD23ABL1RUNX1T1chromosomesRUNX1
Journal Article2012-05-08✓ 1 SnippetPiazza R, Pirola A, Spinelli R, Valletta S, Redaelli S, Magistroni V, Gambacorti-Passerini C.
In-Text Gene Mentions
Results)
…ons (RUNX1–RUNX1T1, EWSR1–ERG,MLLT10–PICAM and PML–RARA), simulati…
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Gene fusions are common driver events in leukaemias and solid tumours; here we present FusionAnalyser, a tool dedicated to the identification of driver fusion rearrangements in human cancer through the analysis of paired-end high-throughput transcriptome sequencing data. We initially tested FusionAnalyser by using a set of in silico randomly generated sequencing data from 20 known human translocations occurring in cancer and subsequently using transcriptome data from three chronic and three acute myeloid leukaemia samples. in all the cases our tool was invariably able to detect the presence of the correct driver fusion event(s) with high specificity. In one of the acute myeloid leukaemia samples, FusionAnalyser identified a novel, cryptic, in-frame ETS2-ERG fusion. A fully event-driven graphical interface and a flexible filtering system allow complex analyses to be run in the absence of any a priori programming or scripting knowledge. Therefore, we propose FusionAnalyser as an efficient and robust graphical tool for the identification of functional rearrangements in the context of high-throughput transcriptome sequencing data.
Also flagged:methylationtumorEsophageal squamous cell carcinomaESCCcancertumor suppressor genes
Journal Article2012-05-08✓ 1 SnippetLi JS, Ying JM, Wang XW, Wang ZH, Tao Q, Li LL.
In-Text Gene Mentions
S I O 001029)⭐ same-sentence co-mention
…Similarly, other genes related to cell adhesion silenced by promoter methylation, such as cadherin 11 (CDH11)[30], cadherin 13 (CDH13)[31] claudin 3 (CLDN3)[32], claudin 4 (CLDN4)[33], deleted in colorectal carcinoma (DCC)[34], low density lipoprotein receptor-related protein 1B (LRP1B)[35], protocadherin 10 (PCDH10)[36], protocadherin 17 (PCDH17)[37], and tumor suppressor in lung cancer 1 (TSLC1)[38], have already been determined to be involved in tumor invasion and metastasis of ESCC (Table 1).…
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Esophageal squamous cell carcinoma (ESCC) is a prevalent and fatal cancer in China and other Asian countries. Epigenetic silencing of key tumor suppressor genes (TSGs) is critical to ESCC initiation and progression. Recently, many novel TSGs silenced by promoter methylation have been identified in ESCC, and these genes further serve as potential tumor markers for high-risk group stratification, early detection, and prognosis prediction. This review summarizes recent discoveries on aberrant promoter methylation of TSGs in ESCC, providing better understanding of the role of disrupted epigenetic regulation in tumorigenesis and insight into diagnostic and prognostic biomarkers for this malignancy.
Also flagged:axon guidanceaxonmembraneextracellularaxons
Journal Article2012-05-08✓ 3 SnippetsGaudin A, Hofmeister W, Key B.
In-Text Gene Mentions
Abstract)
…and its receptorDccare suppressed using…
Abstract)
…either Netrin1a orDcc.…
Abstract)
…traction mediated by Netrin1a-Dccinteractions, follow alternati…
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The development of axon tracts in the early vertebrate brain is controlled by combinations of soluble, membrane-bound and extracellular matrix molecules. How these multiple and sometimes conflicting guidance cues are integrated in order to establish stereotypical pathways remains to be determined. We show here that when interactions between the chemoattractive signal Netrin1a and its receptor Dcc are suppressed using a loss-of-function approach, a novel axon trajectory emerges in the dorsal diencephalon. Axons arising from a subpopulation of telencephalic neurons failed to project rostrally into the anterior commissure in the absence of either Netrin1a or Dcc. Instead these axons inappropriately exited the telencephalon and ectopically coursed caudally into virgin neuroepithelium. This response was highly specific since loss-of-function of Netrin1b, a paralogue of Netrin1a, generated a distinct phenotype in the rostral brain. These results show that a subpopulation of telencephalic neurons, when freed from long-range chemoattraction mediated by Netrin1a-Dcc interactions, follow alternative instructive cues that lead to creation of an ectopic axon bundle in the diencephalon. This work provides insight into how integration of multiple guidance signals defines the initial scaffold of axon tracts in the embryonic vertebrate forebrain.
The Estrogen Receptor (ER) is an established predictive marker for the selection of adjuvant endocrine treatment in early breast cancer. During the 1990s Immunohistochemistry (IHC) replaced cytosol based assays for determination of ER status. This study examined the association between ER protein level determined by two different methods and ESR1 gene copy number. From 289 primary high-risk breast cancer patients, randomized in the Danish Breast Cancer Cooperative Group (DBCG) 77C trial, results from cytosolic ER levels were available from ligand binding assays. Archival tumor tissue was retrieved from 257 patients. ESR1/CEN-6 ratio was analyzed successfully by Fluorescence In Situ Hybridization (FISH) in 220 (86%) patients. ESR1 amplification (ESR1/CEN-6 ≥ 2.00) was observed in 23% of the patients and ESR1 deletion (ESR1/CEN-6 < 0.80) was observed in 32%. Further, we identified ESR1 gain (ratio ESR1/CEN-6 from 1.30 to 1.99) in 19% of the patients. A positive correlation of ESR1 FISH with both ER-cytosol and ER IHC was found (p < 0.0001). Amplification and gain of the ESR1 gene are associated with higher ER protein content measured by ligand binding assay and a more intense nuclear staining by IHC compared to tumors with normal ESR1 gene status. Major variations in ER measured by ligand binding assay and IHC are observed within all ESR1 copy number subgroups and other mechanisms than gene copy number seem to contribute to the ER protein content in the tumors.
Also flagged:ethylenedicysteineglucosaminehexosaminethiazolidine-4-carboxylic acidacetylamino
Journal Article2012-05-08No SnippetsZhang YH, Bryant J, Kong FL, Yu DF, Mendez R, Edmund Kim E, Yang DJ.
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We have developed ethylenedicysteine-glucosamine (ECG) as an alternative to (18)F-fluoro-2-deoxy-D-glucose ((18)F-FDG) for cancer imaging. ECG localizes in the nuclear components of cells via the hexosamine biosynthetic pathway. This study was to evaluate the feasibility of imaging mesothelioma with (99m)Tc-ECG and (68)Ga-ECG. ECG was synthesized from thiazolidine-4-carboxylic acid and 1,3,4,6-tetra-O-acetyl-2-amino-D-glucopyranose, followed by reduction in sodium and liquid ammonia to yield ECG (52%). ECG was chelated with (99m)Tc/tin (II) and (68)Ga/(69)Ga chloride for in vitro and in vivo studies in mesothelioma. The highest tumor uptake of (99m)Tc-ECG is 0.47 at 30 min post injection, and declined to 0.08 at 240 min post injection. Tumor uptake (%ID/g), tumor/lung, tumor/blood, and tumor/muscle count density ratios for (99m)Tc-ECG (30-240 min) were 0.47 ± 0.06 to 0.08 ± 0.01; 0.71 ± 0.07 to 0.85 ± 0.04; 0.47 ± 0.03 to 0.51 ± 0.01, and 3.49 ± 0.24 to 5.06 ± 0.25; for (68)Ga-ECG (15-60 min) were 0.70 ± 0.06 to 0.92 ± 0.08; 0.64 ± 0.05 to 1.15 ± 0.08; 0.42 ± 0.03 to 0.67 ± 0.07, and 3.84 ± 0.52 to 7.00 ± 1.42; for (18)F-FDG (30-180 min) were 1.86 ± 0.22 to 1.38 ± 0.35; 3.18 ± 0.44 to 2.92 ± 0.34, 4.19 ± 0.44 to 19.41 ± 2.05 and 5.75 ± 2.55 to 3.33 ± 0.65, respectively. Tumor could be clearly visualized with (99m)Tc-ECG and (68)Ga-ECG in mesothelioma-bearing rats. (99m)Tc-ECG and (68)Ga-ECG showed increased uptake in mesothelioma, suggesting they may be useful in diagnosing mesothelioma and also monitoring therapeutic response.
Also flagged:epilepsyidiopathic epilepsyidiopathic generalized epilepsychannelopathiesencephalopathiesneuronal migration disorders
Journal Article2012-05-08No SnippetsGarofalo S, Cornacchione M, Di Costanzo A.
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The introduction of DNA microarrays and DNA sequencing technologies in medical genetics and diagnostics has been a challenge that has significantly transformed medical practice and patient management. Because of the great advancements in molecular genetics and the development of simple laboratory technology to identify the mutations in the causative genes, also the diagnostic approach to epilepsy has significantly changed. However, the clinical use of molecular cytogenetics and high-throughput DNA sequencing technologies, which are able to test an entire genome for genetic variants that are associated with the disease, is preparing a further revolution in the near future. Molecular Karyotype and Next-Generation Sequencing have the potential to identify causative genes or loci also in sporadic or non-familial epilepsy cases and may well represent the transition from a genetic to a genomic approach to epilepsy.
…by serotonin transporter (5-HTT) and oxytocin receptor…
Title)
…for OXTR and5-HTTGenes…
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…5-HTT…
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Guided by the affective spillover hypothesis and the differential susceptibility to environmental influence frameworks, the present study examined how associations between interparental conflict and mothers' parenting practices were moderated by serotonin transporter (5-HTT) and oxytocin receptor (OXTR) genes. A sample of 201 mothers and their 2-year old child participated in a laboratory-based research assessment. Results supported differential susceptibility hypotheses within spillover frameworks. With respect to OXTR rs53576, mothers with the GG genotype showed greater differential maternal sensitivity across varying levels of interparental conflict. Mothers with one or two copies of the 5-HTTLPR S allele demonstrated differential susceptibility for both sensitive and harsh/punitive caregiving behaviors. Finally, analyses examined whether maternal depressive symptoms and emotional closeness to their child mediated the moderating effects. Findings suggest that maternal emotional closeness with their child indirectly linked OXTR with maternal sensitivity. The results highlight how molecular genetics may explain heterogeneity in spillover models with differential implications for specific parenting behaviors. Implications for clinicians and therapists working with maritally distressed parents are discussed.
Also flagged:ethanolpolymeraserestriction enzymeagaroserestriction endonucleasescyt-b
Journal Article2012-05-07No SnippetsPfennig KS, Allenby A, Martin RA, Monroy A, Jones CD.
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Two congeneric species of spadefoot toad, Spea multiplicata and Spea bombifrons, have been the focus of hybridization studies since the 1970s. Because complex hybrids are not readily distinguished phenotypically, genetic markers are needed to identify introgressed individuals. We therefore developed a set of molecular markers (amplified fragment length polymorphism, polymerase chain reaction-restriction fragment length polymorphism and single nucleotide polymorphism) for identifying pure-species, F1 hybrids and more complex introgressed types. To do so, we tested a series of markers across both species and known hybrids using populations in both allopatry and sympatry. We retained those markers that differentiated the two pure-species and also consistently identified known species hybrids. These markers are well suited for identifying hybrids between these species. Moreover, those markers that show variation within each species can be used in conjunction with existing molecular markers in studies of population structure and gene flow.
Also flagged:Gbx2Otx2brain developmentPOU factorsBrn1Brn2
Journal Article2012-05-07No SnippetsInoue F, Kurokawa D, Takahashi M, Aizawa S.
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Otx2 plays essential roles in rostral brain development, and its counteraction with Gbx2 has been suggested to determine the midbrain-hindbrain boundary (MHB) in vertebrates. We previously identified the FM enhancer that is conserved among vertebrates and drives Otx2 transcription in forebrain/midbrain from the early somite stage. In this study, we found that the POU homeodomain of class III POU factors (Brn1, Brn2, Brn4, and Oct6) associates with noncanonical target sequence TAATTA in the FM enhancer. MicroRNA-mediated knockdown of Brn2 and Oct6 diminished the FM enhancer activity in anterior neural progenitor cells (NPCs) differentiated from P19 cells. The class III POU factors associate with the FM enhancer in forebrain and midbrain but not in hindbrain. We also demonstrated that the Gbx2 homeodomain recognizes the same target TAATTA in the FM enhancer, and Gbx2 associates with the FM enhancer in hindbrain. Gbx2 misexpression in the anterior NPCs repressed the FM enhancer activity and inhibited Brn2 association with the enhancer, whereas Gbx2 knockdown caused ectopic Brn2 association in the posterior NPCs. These results suggest that class III POU factors and Gbx2 share the same target site, TAATTA, in the FM enhancer and that their region-specific binding restricts Otx2 expression at the MHB.
N-linked glycosylation is one of the most frequent post-translational modifications of proteins with a profound impact on their biological function. Besides other functions, N-linked glycosylation assists in protein folding, determines protein orientation at the cell surface, or protects proteins from proteases. The N-linked glycans attach to asparagines in the sequence context Asn-X-Ser/Thr, where X is any amino acid except proline. Any variation (e.g. non-synonymous single nucleotide polymorphism or mutation) that abolishes the N-glycosylation sequence motif will lead to the loss of a glycosylation site. On the other hand, variations causing a substitution that creates a new N-glycosylation sequence motif can result in the gain of glycosylation. Although the general importance of glycosylation is well known and acknowledged, the effect of variation on the actual glycoproteome of an organism is still mostly unknown. In this study, we focus on a comprehensive analysis of non-synonymous single nucleotide variations (nsSNV) that lead to either loss or gain of the N-glycosylation motif. We find that 1091 proteins have modified N-glycosylation sequons due to nsSNVs in the genome. Based on analysis of proteins that have a solved 3D structure at the site of variation, we find that 48% of the variations that lead to changes in glycosylation sites occur at the loop and bend regions of the proteins. Pathway and function enrichment analysis show that a significant number of proteins that gained or lost the glycosylation motif are involved in kinase activity, immune response, and blood coagulation. A structure-function analysis of a blood coagulation protein, antithrombin III and a protease, cathepsin D, showcases how a comprehensive study followed by structural analysis can help better understand the functional impact of the nsSNVs.
Also flagged:Hepcidinironthalassemiairon overload syndromesynthesisHAMP
Journal Article2012-05-07✓ 5 SnippetsRavasi G, Pelucchi S, Trombini P, Mariani R, Tomosugi N, Modignani GL, Pozzi M, Nemeth E, Ganz T, Hayashi H, Barisani D, Piperno A.
In-Text Gene Mentions
S I O 000419)
…Ratios of HAMP mRNA, serum and urinary hepcidin in controls (NAFLD patients without iron overload), DIOS and HFE-HH patients.…
Methods)
…Quantification of serum hepcidin-25 was performed in 47 DIOS, 21 HFE-HH and 8 THAL patients, as well as in 15 C-NAFLD and 24 C-Donors.…
Results)
…The correction of hepcidin values for the amount of storage iron (serum ferritin and TIS) underscores the inadequate production of hepcidin in HFE-HH and THAL, and the higher values in C-NAFLD and DIOS in the order (Table 3).…
S I O 000419)
…Levels of HAMP mRNA, serum and urinary hepcidin in controls (NAFLD patients without iron overload), DIOS and HFE-HH patients.…
Discussion)
…Second, among patients with iron overload, hepcidin expression was up-regulated in DIOS and patients with NAFLD without iron overload (C-NAFLD) and down-regulated in HFE-HH and THAL.…
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Hepcidin is a regulatory hormone that plays a major role in controlling body iron homeostasis. Circulating factors (holotransferrin, cytokines, erythroid regulators) might variably contribute to hepcidin modulation in different pathological conditions. There are few studies analysing the relationship between hepcidin transcript and related protein expression profiles in humans. Our aims were: a. to measure hepcidin expression at either hepatic, serum and urinary level in three paradigmatic iron overload conditions (hemochromatosis, thalassemia and dysmetabolic iron overload syndrome) and in controls; b. to measure mRNA hepcidin expression in two different hepatic cell lines (HepG2 and Huh-7) exposed to patients and controls sera to assess whether circulating factors could influence hepcidin transcription in different pathological conditions. Our findings suggest that hepcidin assays reflect hepatic hepcidin production, but also indicate that correlation is not ideal, likely due to methodological limits and to several post-trascriptional events. In vitro study showed that THAL sera down-regulated, HFE-HH and C-NAFLD sera up-regulated hepcidin synthesis. HAMP mRNA expression in Huh-7 cells exposed to sera form C-Donors, HFE-HH and THAL reproduced, at lower level, the results observed in HepG2, suggesting the important but not critical role of HFE in hepcidin regulation.
Also flagged:obesityEtv5Faim2Ftotype II diabetesatherosclerosis
Journal Article2012-05-07✓ 4 SnippetsBoender AJ, van Rozen AJ, Adan RA.
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Abstract)
…We show that the expression of Etv5, Faim2, Fto, Negr1 but not Sh2b1 is affected by nutritional state in these two areas, thereby providing insight into the relationship between nutritional state and expression levels of obesity-associated genes in two brain areas relevant to feeding.…
Title)
…Nutritional state affects the expression of the obesity-associated genes Etv5, Faim2, Fto, and Negr1.…
Title)
…Faim2, Fto, andNegr1.…
Abstract)
…Etv5, Faim2, Fto,Negr1but not Sh2b1…
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Obesity is a risk factor for type II diabetes, atherosclerosis, and some forms of cancer. Variation in common measures of obesity (e.g., BMI, waist/hip ratio) is largely explained by heritability. The advent of genome-wide association studies (GWAS) has made it possible to identify several genetic variants that associate with measures of obesity, but how exactly these genetic variants contribute to overweight has remained largely unresolved. One first hint is given by the fact that many of the associated variants reside in or near genes that act in the central nervous system, which implicates neuronal signaling in the etiology of obesity. Although the brain controls both energy intake and expenditure, it has more capacity to regulate energy intake rather than energy expenditure. In environments where food is abundant, this renders the body prone to weight increases. To gain more insight into the neurobiological mechanisms involved, we set out to investigate the effect of dietary exposure on the expression levels of obesity-associated genes in the ventro-medial hypothalamus (VMH)/arcuate nucleus (ARC) and the substantia nigra (SN)/ventral tegmental area (VTA), two brain regions that are implicated in feeding behavior. We show that the expression of Etv5, Faim2, Fto, Negr1 but not Sh2b1 is affected by nutritional state in these two areas, thereby providing insight into the relationship between nutritional state and expression levels of obesity-associated genes in two brain areas relevant to feeding.
Also flagged:ethylene glycolpeptidestumorconjugationwaterethyleneglycol
Journal Article2012-05-07No SnippetsBanerjee SS, Aher N, Patil R, Khandare J.
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Poly(ethylene glycol) (PEG) is the most widely used polymer in delivering anticancer drugs clinically. PEGylation (i.e., the covalent attachment of PEG) of peptides proteins, drugs, and bioactives is known to enhance the aqueous solubility of hydrophobic drugs, prolong circulation time, minimize nonspecific uptake, and achieve specific tumor targetability through the enhanced permeability and retention effect. Numerous PEG-based therapeutics have been developed, and several have received market approval. A vast amount of clinical experience has been gained which has helped to design PEG prodrug conjugates with improved therapeutic efficacy and reduced systemic toxicity. However, more efforts in designing PEG-based prodrug conjugates are anticipated. In light of this, the current paper highlights the synthetic advances in PEG prodrug conjugation methodologies with varied bioactive components of clinical relevance. In addition, this paper discusses FDA-approved PEGylated delivery systems, their intended clinical applications, and formulations under clinical trials.
<h4>Background</h4>The interaction of mast cells (MCs) with regulatory T cells through the OX40 ligand (OX40L):OX40 axis downregulates FcεRI-dependent immediate hypersensitivity responses both in vitro and in vivo. Little is known on OX40L-mediated intracellular signaling or on the mechanism by which OX40L engagement suppresses MC degranulation.<h4>Objective</h4>We explored the role of OX40L engagement on IgE/antigen-triggered MCs both in vitro and in vivo.<h4>Methods</h4>The soluble form of OX40 molecule was used to selectively trigger OX40L on MCs in vitro and was used to dissect OX40L contribution in an in vivo model of systemic anaphylaxis.<h4>Results</h4>OX40L:OX40 interaction led to the recruitment of C-terminal src kinase into lipid rafts, causing a preferential suppression of Fyn kinase activity and subsequent reduction in the phosphorylation of Gab2, the phosphatidylinositol 3-OH kinase regulatory subunit p85, and Akt, without affecting the Lyn pathway. Dampening of Fyn kinase activity also inhibited RhoA activation and microtubule nucleation, key regulators of MC degranulation. The in vivo administration of a blocking antibody to OX40L in wild-type mice caused enhanced immediate hypersensitivity, whereas the administration of soluble OX40 to regulatory T-cell-depleted or OX40-deficient mice reduced MC degranulation.<h4>Conclusions</h4>The engagement of OX40L selectively suppresses Fyn-initiated signals required for MC degranulation and serves to limit immediate hypersensitivity. Our data suggest that soluble OX40 can restore the aberrant or absent regulatory T-cell activity, revealing a previously unappreciated homeostatic role for OX40L in setting the basal threshold of MC response.
Also flagged:gene expressiongastric cancersC20orf11gastric cancerchromosomal regionXPO5
Journal Article2012-05-04No SnippetsCheng L, Cheng L, Wang P, Yang S, Yang Y, Zhang Q, Zhang W, Xiao H, Gao H, Zhang Q.
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<h4>Background</h4>To elucidate gene expression associated with copy number changes, we performed a genome-wide copy number and expression microarray analysis of 25 pairs of gastric tissues.<h4>Methods</h4>We applied laser capture microdissection (LCM) to obtain samples for microarray experiments and profiled DNA copy number and gene expression using 244K CGH Microarray and Human Exon 1.0 ST Microarray.<h4>Results</h4>Obviously, gain at 8q was detected at the highest frequency (70%) and 20q at the second (63%). We also identified molecular genetic divergences for different TNM-stages or histological subtypes of gastric cancers. Interestingly, the C20orf11 amplification and gain at 20q13.33 almost separated moderately differentiated (MD) gastric cancers from poorly differentiated (PD) type. A set of 163 genes showing the correlations between gene copy number and expression was selected and the identified genes were able to discriminate matched adjacent noncancerous samples from gastric cancer samples in an unsupervised two-way hierarchical clustering. Quantitative RT-PCR analysis for 4 genes (C20orf11, XPO5, PUF60, and PLOD3) of the 163 genes validated the microarray results. Notably, some candidate genes (MCM4 and YWHAZ) and its adjacent genes such as PRKDC, UBE2V2, ANKRD46, ZNF706, and GRHL2, were concordantly deregulated by genomic aberrations.<h4>Conclusions</h4>Taken together, our results reveal diverse chromosomal region alterations for different TNM-stages or histological subtypes of gastric cancers, which is helpful in researching clinicopathological classification, and highlight several interesting genes as potential biomarkers for gastric cancer.
Also flagged:fibroproliferative disordercollagenDCtype-1 collagengene expressionDupuytren's Contracture
Journal Article2012-05-04No SnippetsSatish L, LaFramboise WA, Johnson S, Vi L, Njarlangattil A, Raykha C, Krill-Burger JM, Gallo PH, O'Gorman DB, Gan BS, Baratz ME, Ehrlich GD, Kathju S.
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<h4>Background</h4>Dupuytren's contracture (DC) is a fibroproliferative disorder characterized by the progressive development of a scar-like collagen-rich cord that affects the palmar fascia of the hand and leads to digital flexion contractures. DC is most commonly treated by surgical resection of the diseased tissue, but has a high reported recurrence rate ranging from 27% to 80%. We sought to determine if the transcriptomic profiles of fibroblasts derived from DC-affected palmar fascia, adjacent phenotypically normal palmar fascia, and non-DC palmar fascial tissues might provide mechanistic clues to understanding the puzzle of disease predisposition and recurrence in DC.<h4>Methods</h4>To achieve this, total RNA was obtained from fibroblasts derived from primary DC-affected palmar fascia, patient-matched unaffected palmar fascia, and palmar fascia from non-DC patients undergoing carpal tunnel release (6 patients in each group). These cells were grown on a type-1 collagen substrate (to better mimic their in vivo environments). Microarray analyses were subsequently performed using Illumina BeadChip arrays to compare the transcriptomic profiles of these three cell populations. Data were analyzed using Significance Analysis of Microarrays (SAM v3.02), hierarchical clustering, concordance mapping and Venn diagram.<h4>Results</h4>We found that the transcriptomic profiles of DC-disease fibroblasts and fibroblasts from unaffected fascia of DC patients exhibited a much greater overlap than fibroblasts derived from the palmar fascia of patients undergoing carpal tunnel release. Quantitative real time RT-PCR confirmed the differential expression of select genes validating the microarray data analyses. These data are consistent with the hypothesis that predisposition and recurrence in DC may stem, at least in part, from intrinsic similarities in the basal gene expression of diseased and phenotypically unaffected palmar fascia fibroblasts. These data also demonstrate that a collagen-rich environment differentially alters gene expression in these cells. In addition, Ingenuity pathway analysis of the specific biological pathways that differentiate DC-derived cells from carpal tunnel-derived cells has identified the potential involvement of microRNAs in this fibroproliferative disorder.<h4>Conclusions</h4>These data show that the transcriptomic profiles of DC-disease fibroblasts and fibroblasts from unaffected palmar fascia in DC patients are highly similar, and differ significantly from the transcriptomic profiles of fibroblasts from the palmar fascia of patients undergoing carpal tunnel release.
Also flagged:Raf-1 kinaseRaf-1 kinase inhibitorRKIPcolorectal carcinomahepatic colorectal metastasis
Journal Article2012-05-04No SnippetsKim HS, Park SJ, Lee KY, Park YK, Kim YW.
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Reduced expression of Raf-1 kinase inhibitor protein (RKIP) has been documented in a number of human malignancies, including colorectal carcinoma (CRC). However, despite the importance of hepatic colorectal metastasis (HCM) for the prognosis of CRC patients, no studies have been conducted regarding RKIP expression in HCM tissues or its prognostic significance. The aim of this study was to clarify the relationship between reduced RKIP expression and HCM and to identify independent predictors for recurrent HCM, which will ultimately help identify patients at high risk of developing metastatic recurrence. An immunohistochemical study of RKIP expression was performed using primary CRC and/or corresponding HCM tissue samples obtained from 117 patients. Forty-nine of these patients did not harbor HCM and 68 harbored HCM. RKIP expression was reduced in 24.5% (12/49) of CRCs without HCM, 47.1% (32/68) of CRCs with HCM and 67.6% (46/68) of HCM. This distribution of RKIP downregulation was statistically significant. RKIP expression was found to independently predict recurrent HCM, with a higher relative risk (6.661) compared to that of nodal metastasis (4.690). A reduction of RKIP expression in HCM was a significant predictor of poor prognosis. The median survival of patients with reduced RKIP expression was 35 months, compared with more than 10 years in patients with positive RKIP expression. Multivariate survival analysis demonstrated that RKIP expression in HCM was an independent predictor of overall survival, with a hazard ratio of 5.161, a value comparable to the risk associated with advanced TNM stage (5.247). We demonstrated that a reduction of RKIP expression in HCM had an independent predictive value for metastatic recurrence and less favorable clinical outcomes in patients with HCM. Our results strongly suggest that patients harboring HCM with reduced RKIP expression require careful monitoring after hepatic resection to detect potentially resectable metastatic recurrences.
Also flagged:carbamazepinelamivudinezidovudinemetabolismexcretiondihydropyrimidine dehydrogenase
Journal Article2012-05-04✓ 1 SnippetPakhomov S, McInnes BT, Lamba J, Liu Y, Melton GB, Ghodke Y, Bhise N, Lamba V, Birnbaum AK.
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…HFE…
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The main objective of this study was to investigate the feasibility of using PharmGKB, a pharmacogenomic database, as a source of training data in combination with text of MEDLINE abstracts for a text mining approach to identification of potential gene targets for pathway-driven pharmacogenomics research. We used the manually curated relations between drugs and genes in PharmGKB database to train a support vector machine predictive model and applied this model prospectively to MEDLINE abstracts. The gene targets suggested by this approach were subsequently manually reviewed. Our quantitative analysis showed that a support vector machine classifiers trained on MEDLINE abstracts with single words (unigrams) used as features and PharmGKB relations used for supervision, achieve an overall sensitivity of 85% and specificity of 69%. The subsequent qualitative analysis showed that gene targets "suggested" by the automatic classifier were not anticipated by expert reviewers but were subsequently found to be relevant to the three drugs that were investigated: carbamazepine, lamivudine and zidovudine. Our results show that this approach is not only feasible but may also find new gene targets not identifiable by other methods thus making it a valuable tool for pathway-driven pharmacogenomics research.
Also flagged:chromosomeDnaAcell division cyclebindingmembranenucleotide
Journal Article2012-05-04✓ 1 SnippetRegev T, Myers N, Zarivach R, Fishov I.
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Introduction)
…regions DARS1 andDARS2( D na…
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DnaA initiates chromosome replication in most known bacteria and its activity is controlled so that this event occurs only once every cell division cycle. ATP in the active ATP-DnaA is hydrolyzed after initiation and the resulting ADP is replaced with ATP on the verge of the next initiation. Two putative recycling mechanisms depend on the binding of DnaA either to the membrane or to specific chromosomal sites, promoting nucleotide dissociation. While there is no doubt that DnaA interacts with artificial membranes in vitro, it is still controversial as to whether it binds the cytoplasmic membrane in vivo. In this work we looked for DnaA-membrane interaction in E. coli cells by employing cell fractionation with both native and fluorescent DnaA hybrids. We show that about 10% of cellular DnaA is reproducibly membrane-associated. This small fraction might be physiologically significant and represent the free DnaA available for initiation, rather than the vast majority bound to the datA reservoir. Using the combination of mCherry with a variety of DnaA fragments, we demonstrate that the membrane binding function is delocalized on the surface of the protein's domain III, rather than confined to a particular sequence. We propose a new binding-bending mechanism to explain the membrane-induced nucleotide release from DnaA. This mechanism would be fundamental to the initiation of replication.
Also flagged:serotonin transporter5serotoninaffective disorderssynapsesanxiety
Journal Article2012-05-04✓ 5 SnippetsLi S, Zou Q, Li J, Li J, Wang D, Yan C, Dong Q, Zang YF.
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Introduction)
…The serotonin transporter (5-HTT) plays a crucial role in the reuptake of serotonin at brain synapses and it has been widely recognized as the target site of selective serotonin reuptake inhibitors (SSRIs), which have been recognized as both anti-depressant and anti-anxiety drugs [5].…
Introduction)
…The s allele of the 5-HTTLPR polymorphism, which affects the promoter of the 5-HTT gene, causes reduced uptake of the neurotransmitter serotonin into the pre-synaptic cells in the brain [3].…
…The serotonin transporter (5-HTT) plays a crucial…
Introduction)
…variant of the5-HTT-linked polymorphic region (5-…
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<h4>Background</h4>Prior research has shown that the amygdala of carriers of the short allele (s) of the serotonin transporter (5-HTT) gene (5-HTTLPR) have a larger response to negative emotional stimuli and higher spontaneous activity during the resting state than non-carriers. However, recent studies have suggested that the effects of 5-HTTLPR may be specific to different ethnic groups. Few studies have been conducted to address this issue.<h4>Methodology/principal findings</h4>Blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) was conducted on thirty-eight healthy Han Chinese subjects (l/l group, n = 19; s/s group, n = 19) during the resting state and during an emotional processing task. Compared with the s/s group, the l/l group showed significantly increased regional homogeneity or local synchronization in the right amygdala during the resting state (|t|>2.028, p<0.05, corrected), but no significant difference was found in the bilateral amygdala in response to negative stimuli in the emotional processing task.<h4>Conclusions/significance</h4>5-HTTLPR can alter the spontaneous activity of the amygdala in Han Chinese. However, the effect of 5-HTTLPR on the amygdala both in task state and resting state in Asian population was no similar with Caucasians. They suggest that the effect of 5-HTTLPR on the amygdala may be modulated by ethnic differences.
Also flagged:axonaxonalnucleusinnervationaxonsglutamate receptor
Journal Article2012-05-04No SnippetsGrant E, Hoerder-Suabedissen A, Molnár Z.
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In this review we discuss recent advances in the understanding of corticothalamic axon guidance; patterning of the early telencephalon, the sequence and choreography of the development of projections from subplate, layers 5 and 6. These cortical subpopulations display different axonal outgrowth kinetics and innervate distinct thalamic nuclei in a temporal pattern determined by cortical layer identity and subclass specificity. Guidance by molecular cues, structural cues, and activity-dependent mechanisms contribute to this development. There is a substantial rearrangement of the corticofugal connectivity outside the thalamus at the border of and within the reticular thalamic nucleus, a region that shares some of the characteristics of the cortical subplate during development. The early transient circuits are not well understood, nor the extent to which this developmental pattern may be driven by peripheral sensory activity. We hypothesize that transient circuits during embryonic and early postnatal development are critical in the matching of the cortical and thalamic representations and forming the cortical circuits in the mature brain.
We present data on pneumococcal carriage before the introduction of the heptavalent-pneumococcal conjugated vaccine (PCV7) in Denmark. In the pre-PCV7 period, the incidence of invasive pneumococcal disease (IPD) among children younger than 5 years was approximately 25 per 100.000 population, with the highest incidence rates observed in children younger than 2 years of age. The study included 437 children aged 12-72 months attending day care centres (DCC) and was conducted during 48 months. In total, 56% (n=247) of children were pneumococcal carriers with the highest prevalence in children aged 12-23 months (69%), the proportion significantly declining with increasing age. PCV7 serotypes accounted for 33%, PCV10 for 34%, and PCV13 for 57% of all carried isolates. The proportion of serotypes included in the three conjugate vaccines was higher among IPD isolates compared to carrier isolates (range 35- 90%). We found that the frequency of carriage was high among Danish pre-school children attending DCC and serotypes were not frequently covered by PCV7 in the pre-PCV7 period.
Also flagged:glutathionePDdeaththiolperoxiredoxinsthioredoxins
Journal Article2012-05-03No SnippetsGarcia-Garcia A, Zavala-Flores L, Rodriguez-Rocha H, Franco R.
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<h4>Significance</h4>Parkinson's disease (PD) is characterized by the selective loss of dopaminergic neurons of the substantia nigra pars compacta, which has been widely associated with oxidative stress. However, the mechanisms by which redox signaling regulates cell death progression remain elusive.<h4>Recent advances</h4>Early studies demonstrated that depletion of glutathione (GSH), the most abundant low-molecular-weight thiol and major antioxidant defense in cells, is one of the earliest biochemical events associated with PD, prompting researchers to determine the role of oxidative stress in dopaminergic cell death. Since then, the concept of oxidative stress has evolved into redox signaling, and its complexity is highlighted by the discovery of a variety of thiol-based redox-dependent processes regulating not only oxidative damage, but also the activation of a myriad of signaling/enzymatic mechanisms.<h4>Critical issues</h4>GSH and GSH-based antioxidant systems are important regulators of neurodegeneration associated with PD. In addition, thiol-based redox systems, such as peroxiredoxins, thioredoxins, metallothioneins, methionine sulfoxide reductases, transcription factors, as well as oxidative modifications in protein thiols (cysteines), including cysteine hydroxylation, glutathionylation, and nitrosylation, have been demonstrated to regulate dopaminergic cell loss.<h4>Future directions</h4>In this review, we summarize major advances in the understanding of the role of thiol-redox signaling in dopaminergic cell death in experimental PD. Future research is still required to clearly understand how integrated thiol-redox signaling regulates the activation of the cell death machinery, and the knowledge generated should open new avenues for the design of novel therapeutic approaches against PD.
Journal Article2012-05-03✓ 1 SnippetViñas A, Taboada X, Vale L, Robledo D, Hermida M, Vera M, Martínez P.
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Abstract)
…other species (Sox3,Sox6, Sox8, Sox9, Sox17,…
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Production of all-female populations in turbot can increase farmer's benefits since sexual dimorphism in growth in this species is among the highest within marine fish, turbot females reaching commercial size 3-6 months earlier than males. Puberty in males occurs earlier than in females, which additionally slows their growth. Thus, elucidating the mechanisms of sex determination and gonad differentiation is a relevant goal for turbot production. A ZZ/ZW sex determination mechanism has been suggested for this species, and four sex-related quantitative trait loci (QTL) were detected, the major one located in linkage group (LG) 5 and the three minor ones in LG6, LG8, and LG21. In the present work, we carried out a linkage analysis for several sex-related markers: (1) three anonymous sex-associated RAPD and (2) several candidate genes related to sex determination and gonad differentiation in other species (Sox3, Sox6, Sox8, Sox9, Sox17, Sox19, Amh, Dmrta2, Cyp19a, Cyp19b). We focused our attention on their co-localization with the major and minor sex-related QTL trying to approach to the master sex-determining gene of this species. Previously described growth-related QTL were also considered since the association observed between growth and sex determination in fish. Amh, Dmrta2, and one RAPD were located in LG5, while Sox9 and Sox17 (LG21), Cyp19b (LG6), and a second RAPD (LG8) co-mapped with suggestive sex-related QTL, thus supporting further analyses on these genes to elucidate the genetic basis of this relevant trait for turbot farming.
Also flagged:non-alcoholic fatty liver diseaseNAFLDsteatosisNASHliver diseaseAST
Journal Article2012-05-03✓ 1 SnippetPermutt Z, Le TA, Peterson MR, Seki E, Brenner DA, Sirlin C, Loomba R.
In-Text Gene Mentions
Text
…hemochromatosis…
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<h4>Background</h4>Conventional magnetic resonance imaging (MRI) techniques that measure hepatic steatosis are limited by T1 bias, T(2)* decay and multi-frequency signal-interference effects of protons in fat. Newer MR techniques such as the proton density-fat fraction (PDFF) that correct for these factors have not been specifically compared to liver biopsy in adult patients with non-alcoholic fatty liver disease (NAFLD).<h4>Aim</h4>To examine the association between MRI-determined PDFF and histology-determined steatosis grade, and their association with fibrosis.<h4>Methods</h4>A total of 51 adult patients with biopsy-confirmed NAFLD underwent metabolic-biochemical profiling, MRI-determined PDFF measurement of hepatic steatosis and liver biopsy assessment according to NASH-CRN histological scoring system.<h4>Results</h4>The average MRI-determined PDFF increased significantly with increasing histology-determined steatosis grade: 8.9% at grade-1, 16.3% at grade-2, and 25.0% at grade-3 with P ≤ 0.0001 (correlation: r(2) = 0.56, P < 0.0001). Patients with stage-4 fibrosis, when compared with patients with stage 0-3 fibrosis, had significantly lower hepatic steatosis by both MRI-determined PDFF (7.6% vs. 17.8%, P < 0.005) and histology-determined steatosis grade (1.4 vs. 2.2, P < 0.05). NAFLD patients with grade 1 steatosis were more likely to have characteristics of advanced liver disease including higher average AST:ALT (0.87 vs. 0.60, P < 0.02), GGT (140 vs. 67, P < 0.01), and INR (1.06 vs. 0.99, P < 0.01), higher stage of fibrosis and hepatocellular ballooning.<h4>Conclusions</h4>MRI-determined proton density-fat fraction correlates with histology-determined steatosis grade in adults with NAFLD. Steatosis is non-linearly related to fibrosis progression. In patients with NAFLD, a low amount of hepatic steatosis on imaging does not necessarily indicate mild disease.
Also flagged:IGF-1Wntpathogenesisgene expressionthyrotoxicosisorbital disease
Journal Article2012-05-03No SnippetsEzra DG, Krell J, Rose GE, Bailly M, Stebbing J, Castellano L.
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<h4>Aims</h4>The pathogenesis of thyroid-associated orbitopathy (TAO) remains unclear. The aim of this study is to elucidate the gene expression profile of orbital fat from patients with active, but untreated, TAO.<h4>Methods</h4>A case-control gene expression study was conducted using test samples of orbital fat from TAO patients and control orbital fat specimens; apart from drugs to control thyrotoxicosis, the TAO patients had received no treatment for orbital disease. cDNA expression analysis was performed using the Affymetrix GeneChip Human Genome U133 Plus 2.0 platform and validated using quantitative PCR.<h4>Results</h4>The highest-ranked differentially expressed genes were dominated by IGF-1 signalling genes. These include IGF-1, IGF-1 receptor binding/signalling genes, such as SOCS3 and IRS2, and downstream signalling and transcriptional regulators, such as SGK (PDK/Akt signalling) and c-JUN. Our microarray data also demonstrate dysregulation of wingless-type MMTV (Wnt) signalling gene expression, including Wnt5a, sFRPs and DKK.<h4>Conclusion</h4>Altered Wnt signalling confirms previous array findings. Further investigation of the role of Wnt signalling in TAO pathogenesis is warranted. These data also provide the first evidence of dysregulation of IGF-1 pathway genes in TAO tissue, further strengthening the evidence for the role of IGF-1 signalling in the pathogenesis and potential treatment of TAO.
Also flagged:tumorMYCliver cancerliver tumorNcoa2diethylnitrosamine
Journal Article2012-05-03✓ 1 SnippetO'Donnell KA, Keng VW, York B, Reineke EL, Seo D, Fan D, Silverstein KA, Schrum CT, Xie WR, Mularoni L, Wheelan SJ, Torbenson MS, O'Malley BW, Largaespada DA, Boeke JD.
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…Rc3h1…
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The Sleeping Beauty (SB) transposon mutagenesis system is a powerful tool that facilitates the discovery of mutations that accelerate tumorigenesis. In this study, we sought to identify mutations that cooperate with MYC, one of the most commonly dysregulated genes in human malignancy. We performed a forward genetic screen with a mouse model of MYC-induced liver cancer using SB-mediated mutagenesis. We sequenced insertions in 63 liver tumor nodules and identified at least 16 genes/loci that contribute to accelerated tumor development. RNAi-mediated knockdown in a liver progenitor cell line further validate three of these genes, Ncoa2/Src-2, Zfx, and Dtnb, as tumor suppressors in liver cancer. Moreover, deletion of Ncoa2/Src-2 in mice predisposes to diethylnitrosamine-induced liver tumorigenesis. These findings reveal genes and pathways that functionally restrain MYC-mediated liver tumorigenesis and therefore may provide targets for cancer therapy.
Also flagged:Huntington diseaseneurodegenerative disorderMyo5aPrkraPACTGnb2l1
Journal Article2012-05-03✓ 5 SnippetsCulver BP, Savas JN, Park SK, Choi JH, Zheng S, Zeitlin SO, Yates JR, Tanese N.
In-Text Gene Mentions
Abstract)
…Cumulatively, these data support a new role for Htt in translation and provide impetus for further study into the link between protein synthesis and Huntington disease pathogenesis.…
Abstract)
…Huntington disease is a neurodegenerative disorder caused by a CAG repeat amplification in the gene huntingtin (HTT) that is reflected by a polyglutamine expansion in the Htt protein.…
Abstract)
…expansion in theHttprotein.…
Abstract)
…uncovered roles forHttin a wide…
Abstract)
…the identification ofHtt-interacting proteins.…
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Huntington disease is a neurodegenerative disorder caused by a CAG repeat amplification in the gene huntingtin (HTT) that is reflected by a polyglutamine expansion in the Htt protein. Nearly 20 years of research have uncovered roles for Htt in a wide range of cellular processes, and many of these discoveries stemmed from the identification of Htt-interacting proteins. However, no study has employed an impartial and comprehensive strategy to identify proteins that differentially associate with full-length wild-type and mutant Htt in brain tissue, the most relevant sample source to the disease condition. We analyzed Htt affinity-purified complexes from wild-type and HTT mutant juvenile mouse brain from two different biochemical fractions by tandem mass spectrometry. We compared variations in protein spectral counts relative to Htt to identify those proteins that are the most significantly contrasted between wild-type and mutant Htt purifications. Previously unreported Htt interactions with Myo5a, Prkra (PACT), Gnb2l1 (RACK1), Rps6, and Syt2 were confirmed by Western blot analysis. Gene Ontology analysis of these and other Htt-associated proteins revealed a statistically significant enrichment for proteins involved in translation among other categories. Furthermore, Htt co-sedimentation with polysomes in cytoplasmic mouse brain extracts is dependent upon the presence of intact ribosomes. Finally, wild-type or mutant Htt overexpression inhibits cap-dependent translation of a reporter mRNA in an in vitro system. Cumulatively, these data support a new role for Htt in translation and provide impetus for further study into the link between protein synthesis and Huntington disease pathogenesis.
Also flagged:Ironcytidine deaminaseIghypermutationantibodyActivation-induced cytidine deaminase
Journal Article2012-05-03✓ 1 SnippetLi G, Pone EJ, Tran DC, Patel PJ, Dao L, Xu Z, Casali P.
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…hemochromatosis…
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Immunoglobulin (Ig) class switch DNA recombination (CSR) and somatic hypermutation (SHM) are critical for the maturation of the antibody response. Activation-induced cytidine deaminase (AID) initiates CSR and SHM by deaminating deoxycytidines (dCs) in switch (S) and V(D)J region DNA, respectively, to generate deoxyuracils (dUs). Processing of dUs by uracil DNA glycosylase (UNG) yields abasic sites, which are excised by apurinic/apyrimidinic endonucleases, eventually generating double strand DNA breaks, the obligatory intermediates of CSR. Here, we found that the bivalent iron ion (Fe(2+), ferrous) suppressed CSR, leading to decreased number of switched B cells, decreased postrecombination Iμ-C(H) transcripts, and reduced titers of secreted class-switched IgG1, IgG3, and IgA antibodies, without alterations in critical CSR factors, such as AID, 14-3-3γ, or PTIP, or in general germline I(H)-S-C(H) transcription. Fe(2+) did not affect B cell proliferation or plasmacytoid differentiation. Rather, it inhibited AID-mediated dC deamination in a dose-dependent fashion. The inhibition of intrinsic AID enzymatic activity by Fe(2+) was specific, as shown by lack of inhibition of AID-mediated dC deamination by other bivalent metal ions, such as Zn(2+), Mn(2+), Mg(2+), or Ni(2+), and the inability of Fe(2+) to inhibit UNG-mediated dU excision. Overall, our findings have outlined a novel role of iron in modulating a B cell differentiation process that is critical to the generation of effective antibody responses to microbial pathogens and tumoral cells. They also suggest a possible role of iron in dampening AID-dependent autoimmunity and neoplastic transformation.
Also flagged:transferrin receptortransferrin receptor type-1TfRbindingTFRCamino acid
Journal Article2012-05-03✓ 4 SnippetsKaelber JT, Demogines A, Harbison CE, Allison AB, Goodman LB, Ortega AN, Sawyer SL, Parrish CR.
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Introduction)
…The TfR also binds to the hemochromatosis (HFE) protein which competes with the binding of Tf to regulate the uptake of iron from the intestine [14].…
Introduction)
…binds to thehemochromatosis(HFE) protein which…
Introduction)
…to the hemochromatosis (HFE) protein which competes…
Results)
…in Tf andHFEbinding, and canine…
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Parvoviruses exploit transferrin receptor type-1 (TfR) for cellular entry in carnivores, and specific interactions are key to control of host range. We show that several key mutations acquired by TfR during the evolution of Caniforms (dogs and related species) modified the interactions with parvovirus capsids by reducing the level of binding. These data, along with signatures of positive selection in the TFRC gene, are consistent with an evolutionary arms race between the TfR of the Caniform clade and parvoviruses. As well as the modifications of amino acid sequence which modify binding, we found that a glycosylation site mutation in the TfR of dogs which provided resistance to the carnivore parvoviruses which were in circulation prior to about 1975 predates the speciation of coyotes and dogs. Because the closely-related black-backed jackal has a TfR similar to their common ancestor and lacks the glycosylation site, reconstructing this mutation into the jackal TfR shows the potency of that site in blocking binding and infection and explains the resistance of dogs until recent times. This alters our understanding of this well-known example of viral emergence by indicating that canine parvovirus emergence likely resulted from the re-adaptation of a parvovirus to the resistant receptor of a former host.
Also flagged:primary open-angle glaucomaglaucomaGAS7TMCO1-Angle Glaucomaeye disease
Journal Article2012-05-03No Snippetsvan Koolwijk LM, Ramdas WD, Ikram MK, Jansonius NM, Pasutto F, Hysi PG, Macgregor S, Janssen SF, Hewitt AW, Viswanathan AC, ten Brink JB, Hosseini SM, Amin N, Despriet DD, Willemse-Assink JJ, Kramer R, Rivadeneira F, Struchalin M, Aulchenko YS, Weisschuh N, Zenkel M, Mardin CY, Gramer E, Welge-Lüssen U, Montgomery GW, Carbonaro F, Young TL, DCCT/EDIC Research Group, Bellenguez C, McGuffin P, Foster PJ, Topouzis F, Mitchell P, Wang JJ, Wong TY, Czudowska MA, Hofman A, Uitterlinden AG, Wolfs RC, de Jong PT, Oostra BA, Paterson AD, Wellcome Trust Case Control Consortium 2, Mackey DA, Bergen AA, Reis A, Hammond CJ, Vingerling JR, Lemij HG, Klaver CC, van Duijn CM.
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Intraocular pressure (IOP) is a highly heritable risk factor for primary open-angle glaucoma and is the only target for current glaucoma therapy. The genetic factors which determine IOP are largely unknown. We performed a genome-wide association study for IOP in 11,972 participants from 4 independent population-based studies in The Netherlands. We replicated our findings in 7,482 participants from 4 additional cohorts from the UK, Australia, Canada, and the Wellcome Trust Case-Control Consortium 2/Blue Mountains Eye Study. IOP was significantly associated with rs11656696, located in GAS7 at 17p13.1 (p=1.4×10(-8)), and with rs7555523, located in TMCO1 at 1q24.1 (p=1.6×10(-8)). In a meta-analysis of 4 case-control studies (total N = 1,432 glaucoma cases), both variants also showed evidence for association with glaucoma (p=2.4×10(-2) for rs11656696 and p=9.1×10(-4) for rs7555523). GAS7 and TMCO1 are highly expressed in the ciliary body and trabecular meshwork as well as in the lamina cribrosa, optic nerve, and retina. Both genes functionally interact with known glaucoma disease genes. These data suggest that we have identified two clinically relevant genes involved in IOP regulation.
Also flagged:H3K27 demethylasegene expressionUTXhistone demethylasecatalytic activityMLL
Journal Article2012-05-03✓ 2 SnippetsVandamme J, Lettier G, Sidoli S, Di Schiavi E, Nørregaard Jensen O, Salcini AE.
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Discussion)
…dosage compensation complex (DCC) [34] .…
Discussion)
…and that theDCChas been recently…
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Epigenetic modifications influence gene expression and provide a unique mechanism for fine-tuning cellular differentiation and development in multicellular organisms. Here we report on the biological functions of UTX-1, the Caenorhabditis elegans homologue of mammalian UTX, a histone demethylase specific for H3K27me2/3. We demonstrate that utx-1 is an essential gene that is required for correct embryonic and postembryonic development. Consistent with its homology to UTX, UTX-1 regulates global levels of H3K27me2/3 in C. elegans. Surprisingly, we found that the catalytic activity is not required for the developmental function of this protein. Biochemical analysis identified UTX-1 as a component of a complex that includes SET-16(MLL), and genetic analysis indicates that the defects associated with loss of UTX-1 are likely mediated by compromised SET-16/UTX-1 complex activity. Taken together, these results demonstrate that UTX-1 is required for many aspects of nematode development; but, unexpectedly, this function is independent of its enzymatic activity.
Journal Article2012-05-03No SnippetsSingh RK, Gonzalez M, Kabbaj MH, Gunjan A.
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Core histone proteins are essential for packaging the genomic DNA into chromatin in all eukaryotes. Since multiple genes encode these histone proteins, there is potential for generating more histones than what is required for chromatin assembly. The positively charged histones have a very high affinity for negatively charged molecules such as DNA, and any excess of histone proteins results in deleterious effects on genomic stability and cell viability. Hence, histone levels are known to be tightly regulated via transcriptional, posttranscriptional and posttranslational mechanisms. We have previously elucidated the posttranslational regulation of histone protein levels by the ubiquitin-proteasome pathway involving the E2 ubiquitin conjugating enzymes Ubc4/5 and the HECT (Homologous to E6-AP C-Terminus) domain containing E3 ligase Tom1 in the budding yeast. Here we report the identification of four additional E3 ligases containing the RING (Really Interesting New Gene) finger domains that are involved in the ubiquitylation and subsequent degradation of excess histones in yeast. These E3 ligases are Pep5, Snt2 as well as two previously uncharacterized Open Reading Frames (ORFs) YKR017C and YDR266C that we have named Hel1 and Hel2 (for Histone E3 Ligases) respectively. Mutants lacking these E3 ligases are sensitive to histone overexpression as they fail to degrade excess histones and accumulate high levels of endogenous histones on histone chaperones. Co-immunoprecipitation assays showed that these E3 ligases interact with the major E2 enzyme Ubc4 that is involved in the degradation related ubiquitylation of histones. Using mutagenesis we further demonstrate that the RING domains of Hel1, Hel2 and Snt2 are required for histone regulation. Lastly, mutants corresponding to Hel1, Hel2 and Pep5 are sensitive to replication inhibitors. Overall, our results highlight the importance of posttranslational histone regulatory mechanisms that employ multiple E3 ubiquitin ligases to ensure excess histone degradation and thus contribute to the maintenance of genomic stability.
Also flagged:cognitive deficitsschizophreniaNicotine Dependencecognitive impairmentschizophrenicCognition
Journal Article2012-05-03No SnippetsZhang XY, Chen DC, Xiu MH, Haile CN, Sun H, Lu L, Kosten TA, Kosten TR.
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Schizophrenic patients have higher smoking rates than the general population. Studies show that smoking may be a form of self-medication in an attempt to alleviate cognitive deficits in schizophrenic patients of European background. This study examined the relationships between smoking and cognitive deficits in Chinese schizophrenic patients, which have previously received little systemic study. We recruited 580 male chronic patients meeting DSM-IV criteria for schizophrenia and 175 male control subjects who were matched on age and education. The subjects completed a detailed cigarette smoking questionnaire, the Fagerstrom Test for Nicotine Dependence (FTND), and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Patients also were rated on the Positive and Negative Symptom Scale (PANSS), the Simpson and Angus Extrapyramidal Symptom Rating Scale (SAES), and the Abnormal Involuntary Movement Scale (AIMS). All five RBANS subscales except for the Visuospatial/Constructional index showed significantly lower cognitive performance for schizophrenics than normal controls. The schizophrenic smokers scored lower than the schizophrenic non-smokers on the RBANS total score and the Visuospatial/Constructional and Immediate Memory indices. Similarly, the control smokers scored lower than the control non-smokers on the RBANS total score and the Immediate Memory index . Also, the schizophrenic smokers consistently performed the poorest on the cognitive domains of the RBANS. Among the schizophrenic patients, smokers displayed significantly fewer negative symptoms than non-smokers. Using multivariate regression analysis the following variables were independently associated with the RBANS total score: years of education, PANSS negative symptom score, age at schizophrenia onset, and number of hospitalizations. Our results show that smoking is associated with significant cognitive impairment in both schizophrenic patients and normal controls, but the smokers with schizophrenia had a reduced level of negative symptoms, suggesting that the benefits of smoking for those with schizophrenia may be limited to certain aspects of a given clinical phenotype.
Also flagged:viral meningoencephalitisred fluorescent proteinInfectiondistemperpathogenesisacute viral meningitis
Journal Article2012-05-02No SnippetsLudlow M, Nguyen DT, Silin D, Lyubomska O, de Vries RD, von Messling V, McQuaid S, De Swart RL, Duprex WP.
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The propensity of canine distemper virus (CDV) to spread to the central nervous system is one of the primary features of distemper. Therefore, we developed a reverse genetics system based on the neurovirulent Snyder Hill (SH) strain of CDV (CDV(SH)) and show that this virus rapidly circumvents the blood-brain and blood-cerebrospinal fluid (CSF) barriers to spread into the subarachnoid space to induce dramatic viral meningoencephalitis. The use of recombinant CDV(SH) (rCDV(SH)) expressing enhanced green fluorescent protein (EGFP) or red fluorescent protein (dTomato) facilitated the sensitive pathological assessment of routes of virus spread in vivo. Infection of ferrets with these viruses led to the full spectrum of clinical signs typically associated with distemper in dogs during a rapid, fatal disease course of approximately 2 weeks. Comparison with the ferret-adapted CDV(5804P) and the prototypic wild-type CDV(R252) showed that hematogenous infection of the choroid plexus is not a significant route of virus spread into the CSF. Instead, viral spread into the subarachnoid space in rCDV(SH)-infected animals was triggered by infection of vascular endothelial cells and the hematogenous spread of virus-infected leukocytes from meningeal blood vessels into the subarachnoid space. This resulted in widespread infection of cells of the pia and arachnoid mater of the leptomeninges over large areas of the cerebral hemispheres. The ability to sensitively assess the in vivo spread of a neurovirulent strain of CDV provides a novel model system to study the mechanisms of virus spread into the CSF and the pathogenesis of acute viral meningitis.
In any mitotic cell, the orientation of the mitotic spindle determines the orientation of the cleavage plane and therefore the position of the two daughter cells. When combined with polarization of cellular components, spindle orientation is also a well-conserved means of generating daughter cells with asymmetric cell fates, such as progenitors and differentiated cell types. In the mammalian neocortex, the precise planar spindle orientation observed early during development is vital for symmetric proliferative divisions. During later stages, spindles can be oblique or even vertical but the role of this reorientation is somewhat less clear as asymmetric cell fates can arise independently of spindle orientation during this stage. Although decades of work have identified many key conserved regulators of spindle positioning, its precise role in cell fate determination in the mammalian neocortex has been enigmatic. Recent work focused on mInsc and LGN has now revealed an important role for spindle orientation in determination of specific asymmetric cell fates, namely intermediate progenitors and a new progenitor population, termed outer radial glia. In this way, spindle orientation helps determine the neurogenic outcome of asymmetric progenitor divisions, thereby influencing neuron output and cerebral cortical expansion.
Also flagged:chromatinnucleotideshistone proteinsnucleosomesmodifyingtranscription factor
Journal Article2012-05-02✓ 1 SnippetBryant B.
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Discussion)
…researchers used humanpolycomb chromatinchromatin protein and…
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In living cells, DNA is packaged along with protein and RNA into chromatin. Chemical modifications to nucleotides and histone proteins are added, removed and recognized by multi-functional molecular complexes. Here I define a new computational model, in which chromatin modifications are information units that can be written onto a one-dimensional string of nucleosomes, analogous to the symbols written onto cells of a Turing machine tape, and chromatin-modifying complexes are modeled as read-write rules that operate on a finite set of adjacent nucleosomes. I illustrate the use of this "chromatin computer" to solve an instance of the Hamiltonian path problem. I prove that chromatin computers are computationally universal--and therefore more powerful than the logic circuits often used to model transcription factor control of gene expression. Features of biological chromatin provide a rich instruction set for efficient computation of nontrivial algorithms in biological time scales. Modeling chromatin as a computer shifts how we think about chromatin function, suggests new approaches to medical intervention, and lays the groundwork for the engineering of a new class of biological computing machines.
Also flagged:Huntington DiseaseHDneurological disordercalcium-binding proteinsparvalbumincalbindin
Journal Article2012-05-02No SnippetsDougherty SE, Reeves JL, Lucas EK, Gamble KL, Lesort M, Cowell RM.
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Huntington Disease (HD) is a devastating neurological disorder characterized by progressive deterioration of psychiatric, motor, and cognitive function. Purkinje cells (PCs), the output neurons of the cerebellar cortex, have been found to be vulnerable in multiple CAG repeat disorders, but little is known about the involvement of PC dysfunction in HD. To investigate possible PC abnormalities, we performed quantitative real time PCR, Western blot analysis, and immunohistochemistry experiments to explore the changes in PC markers in the R6/2 mouse model of severe HD. There were reductions in the transcript and protein levels of the calcium-binding proteins parvalbumin and calbindin, as well as the enzyme glutamic acid decarboxylase 67. Immunohistochemistry supported these results, with the most substantial changes occurring in the PC layer. To determine whether the reductions in PC marker expression were due to cell loss, we performed stereology on both presymptomatic and end-stage R6/2 mice. Stereological counts indicated a significant reduction in PC number by end-stage but no change in presymptomatic animals (4 weeks of age). To assess cellular function prior to cell loss and symptom onset, we measured spontaneous firing in PCs from 4-week old animals and found a striking deficit in PC firing as indicated by a 57% decrease in spike rate. Interestingly, huntingtin inclusions were not widely observed in PCs until 12 weeks of age, indicating that soluble huntingtin and/or abnormalities in other cell types may contribute to PC dysfunction. Considering the roles for PCs in motor control, these data suggest that early PC dysfunction potentially contributes to motor impairment in this model of HD.
Also flagged:desferrioxamine Bciprofloxacinesterasephosphataseferrioxaminephophatase
Journal Article2012-05-02No SnippetsJi C, Miller MJ.
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Two desferrioxamine B-ciprofloxacin conjugates with 'trimethyl-lock' based linkers that are designed to release the antibiotic after esterase or phosphatase-mediated hydrolysis were synthesized. The potential esterase-sensitive conjugate 13 displayed moderate to good antibacterial activities against selected ferrioxamine-utilizing bacteria, although the activities were lower than the parent drug ciprofloxacin. However, the potential phophatase-sensitive conjugate 23 was inactive against the same panel of organisms tested. These properties appeared to be related to the activating efficiency of the linker by the enzyme and to the outer membrane protein recognition of the chemically modified siderophore used in the conjugate.
Also flagged:Serotoninserotonin receptorserotonin receptors
Journal Article2012-05-02✓ 1 SnippetBerumen LC, Rodríguez A, Miledi R, García-Alcocer G.
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S I O 001029)
…The “specific” 5-HT1A ligand 8-OH-DPAT has been used to establish the roles of this receptor as trophic factor and in neurotransmission as well, but 5-HTT (SERT) recognizes this ligand and likewise modulates anxiety-related behaviour [136, 155].…
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Serotonin is an ancient molecular signal and a recognized neurotransmitter brainwide distributed with particular presence in hippocampus. Almost all serotonin receptor subtypes are expressed in hippocampus, which implicates an intricate modulating system, considering that they can be localized as autosynaptic, presynaptic, and postsynaptic receptors, even colocalized within the same cell and being target of homo- and heterodimerization. Neurons and glia, including immune cells, integrate a functional network that uses several serotonin receptors to regulate their roles in this particular part of the limbic system.
Also flagged:delta-protocadherinsProtocadherinscadherindelta-protocadherincadherinsPcdh8
Journal Article2012-05-01No SnippetsLin J, Wang C, Redies C.
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Protocadherins constitute the largest subfamily of cadherin genes and are widely expressed in the nervous system. In the present study, we cloned eight members of the delta-protocadherin subfamily of cadherins (Pcdh1, Pcdh7, Pcdh8, Pcdh9, Pcdh10, Pcdh17, Pcdh18, and Pcdh19) from the chicken, and investigated their expression in the developing chicken spinal cord by in situ hybridization. Our results showed that each of the investigated delta-protocadherins exhibits a spatially restricted and temporally regulated pattern of expression. Pcdh1, Pcdh8, Pcdh18, and Pcdh19 are expressed in restricted dorsoventral domains of the neuroepithelial layer at early developmental stages (E2.5–E4). In the differentiating mantle layer, specific expression profiles are observed for all eight delta-protocadherins along the dorsoventral, mediolateral, and rostrocaudal dimensions at intermediate stages of development (E6–E10). Expression profiles are especially diverse in the motor column, where different pools of motor neurons exhibit signal for subsets of delta-protocadherins. In the dorsal root ganglion, subpopulations of cells express combinations of Pcdh1, Pcdh7, Pcdh8, Pcdh9, Pcdh10, and Pcdh17. The ventral boundary cap cells are positive for Pcdh7, Pcdh9, and Pcdh10. Signals for Pcdh8, Pcdh18, and Pcdh19 are found in the meninges. Surrounding tissues, such as the notochord, dermomyotome, and sclerotome also exhibit differential expression patterns. The highly regulated spatiotemporal expression patterns of delta-protocadherins suggest that they have multiple and diverse functions during development of the spinal cord and its surrounding tissues.
<h4>Objectives</h4>To determine if community population screening studies for hemochromatosis affected HFE genetic screening practices in non-study populations.<h4>Methods</h4>An audit of all genetic testing for HFE mutations at London Health Sciences Center, London, Ontario, Canada from 1997 to 2010 was performed. The frequency of genetic testing and the frequency of C282Y homozygous cases identified during the years of the London Red Cross (1998-1999) and HEIRS (2000-2005) screening studies were compared with the corresponding frequencies in the specified years outside this range (1997-1998 and 2006-2010).<h4>Results</h4>An increase in HFE gene mutation testing is seen during the London Red Cross study, and the frequency of testing rose further during the HEIRS study. Genetic screening activity continued to increase in the years after publication of the HEIRS study. The proportion of patients with homozygosity for C282Y mutation remained relatively constant despite fluctuations in numbers of persons screened per annum.<h4>Conclusions</h4>The rise in HFE gene testing among non-study populations during the HH studies could be explained by the Hawthorne effect, a phenomenon referring to the improvement or modification of behavior by a population as a consequence of it being studied. In this case, we postulate that primary care physicians at our center performed more HFE gene tests for their patients as a consequence of being affected by knowledge of the screening studies. Despite a general increase in testing during and after completion of the studies, the total number of hemochromatosis cases (C282Y homozygotes) diagnosed per annum remained relatively constant.
Also flagged:IronmetabolismFerritinTransferrinarthritisdiabetes
Journal Article2012-05-01✓ 5 SnippetsSpeechley M, Alter D, Guo H, Harrison H, Adams PC.
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Abstract)
…A primary care-based cohort of 20,306 participants (Hemochromatosis and Iron Overload Study, Ontario site) were tested for the C282Y and H63D mutations of the HFE gene and for abnormal serum ferritin (SF) and transferrin saturation levels.…
Abstract)
…The reference group had no HFE mutations (wild type) and normal transferrin saturation/SF values.<h4>Results</h4>Participants with an ambiguous hemochromatosis gene test and normal iron levels had statistically significantly higher average physician utilization of 3.0%.…
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…Effect of ambiguoushemochromatosisgene test results…
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…Hemochromatosis…
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…HFE…
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<h4>Background</h4>Genetic test results may be available to greater numbers of people through genetic screening projects and other means. The effects of widespread genetic testing and notification of genetic test results, particularly added costs through increased physician utilization, have not been clearly established.<h4>Methods</h4>A primary care-based cohort of 20,306 participants (Hemochromatosis and Iron Overload Study, Ontario site) were tested for the C282Y and H63D mutations of the HFE gene and for abnormal serum ferritin (SF) and transferrin saturation levels. The primary outcome variable was the total number of physician claims per patient after genetic test notification by mail. Multiple Poisson regression was used to adjust for age, sex, baseline SF, diagnoses of arthritis, diabetes, heart failure and impotence, self-rated health, and the number of claims during the 12 months before notification of results. The reference group had no HFE mutations (wild type) and normal transferrin saturation/SF values.<h4>Results</h4>Participants with an ambiguous hemochromatosis gene test and normal iron levels had statistically significantly higher average physician utilization of 3.0%. Participants with HFE mutations (excluding C282Y homozygotes) and elevated iron values showed a 6% increase in physician utilization.<h4>Conclusions</h4>The health effects, if any, of increased utilization in heterozygotes or those with mild ferritin elevations are unknown but are unlikely to be large at the population level. Ambiguous genetic test results are associated with increased physician service use and should be considered when assessing the complete societal costs of widespread genetic testing.
Also flagged:hereditary hemochromatosisHHoxygencarbon dioxideIroncardiac arrhythmias
Journal Article2012-05-01✓ 1 SnippetShizukuda Y, Smith KP, Tripodi DJ, Arena R, Yau YY, Bolan CD, Waclawiw MA, Leitman SF, Rosing DR.
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…HFE…
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<h4>Objective</h4>A long-term effect of hereditary hemochromatosis (HH) on aerobic exercise capacity (AEC) has not been well described.<h4>Design</h4>Forty-three HH and 21 volunteer control subjects who were asymptomatic underwent cardiopulmonary exercise testing using the Bruce protocol. AEC was assessed with minute ventilation (V(E)), oxygen uptake (V(O)(2)), and carbon dioxide production (V(CO)(2)) at baseline and at a follow-up assessment after 5 yrs. A paired t test was used for analyses of normality data; otherwise, Wilcoxon's signed rank-sum test was used.<h4>Results</h4>Thirty-three HH subjects and 18 volunteer control subjects returned for a repeat cardiopulmonary exercise testing at the fifth-year follow-up (80% overall return rate). At the fifth-year follow-up, AEC was not different between the two groups. Compared with baseline measurements, exercise time, peak V(O)(2), and the V(E)/V(CO)(2) slope did not differ statistically at the fifth-year follow-up between both groups. Iron depletion through phlebotomy for 5 yrs did not significantly affect AEC in newly diagnosed HH subjects at baseline (n = 14) and cardiac arrhythmias during exercise tended to decrease after 5 yrs of therapy in this group.<h4>Conclusions</h4>The AEC of asymptomatic HH subjects treated using conventional therapy is not statistically affected by the disease during a 5-yr period.
…These results suggest that FE65 facilitates the accumulation of mutant Htt in cells by preventing its degradation via the UPS, and thereby enhances the toxicity of mutant Htt.…
Abstract)
…An unstable expansion of the polyglutamine repeat within exon 1 of the protein Htt (huntingtin) causes HD (Huntington's disease).…
Abstract)
…Understanding the degradation mechanism of mutant Htt and improving its clearance has emerged as a new direction in developing therapeutic approaches to treat HD.…
Abstract)
…of the proteinHtt(huntingtin) causes HD…
Abstract)
…of N-terminal mutantHttfragments is the…
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An unstable expansion of the polyglutamine repeat within exon 1 of the protein Htt (huntingtin) causes HD (Huntington's disease). Mounting evidence shows that accumulation of N-terminal mutant Htt fragments is the source of disruption of normal cellular processes which ultimately leads to neuronal cell death. Understanding the degradation mechanism of mutant Htt and improving its clearance has emerged as a new direction in developing therapeutic approaches to treat HD. In the present study we show that the brain-enriched adaptor protein FE65 is a novel interacting partner of Htt. The binding is mediated through WW-polyproline interaction and is dependent on the length of the polyglutamine tract. Interestingly, a reduction in mutant Htt protein level was observed in FE65-knockdown cells, and the process requires the UPS (ubiquitin/proteasome system). Moreover, the ubiquitination level of mutant Htt was found to be enhanced when FE65 is knocked down. Immunofluroescence staining revealed that FE65 associates with mutant Htt aggregates. Additionally, we demonstrated that overexpression of FE65 increases mutant Htt-induced cell death both in vitro and in vivo. These results suggest that FE65 facilitates the accumulation of mutant Htt in cells by preventing its degradation via the UPS, and thereby enhances the toxicity of mutant Htt.
The use of model organisms to provide information on gene function has proved to be a powerful approach to our understanding of both human disease and fundamental mammalian biology. Large-scale community projects using mice, based on forward and reverse genetics, and now the pan-genomic phenotyping efforts of the International Mouse Phenotyping Consortium, are generating resources on an unprecedented scale, which will be extremely valuable to human genetics and medicine. We discuss the nature and availability of data, mice and embryonic stem cells from these large-scale programmes, the use of these resources to help prioritize and validate candidate genes in human genetic association studies, and how they can improve our understanding of the underlying pathobiology of human disease.
Also flagged:Statinacute respiratory distress syndromestatinsfailure3-hydroxy-3-methylglutaryl-coenzyme A reductaseARDS
Journal Article2012-05-01No SnippetsBajwa EK, Malhotra CK, Thompson BT, Christiani DC, Gong MN.
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<h4>Objectives</h4>The 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors ("statins") have anti-inflammatory properties and are associated with improved outcomes in critically ill patients. We investigated whether previous statin therapy affects outcomes in patients at risk for acute respiratory distress syndrome.<h4>Design</h4>Patients were followed-up for the primary outcome of acute respiratory distress syndrome and secondary outcomes of intensive care unit and 60-day mortality, organ dysfunction, and ventilator-free days in a secondary analysis of a prospective cohort study. Receipt of statin therapy was recorded. Propensity score matching was used to adjust for confounding by indication.<h4>Setting</h4>Intensive care units at a tertiary care academic medical center.<h4>Patients</h4>Critically ill patients (2,743) with acute respiratory distress syndrome risk factors.<h4>Interventions</h4>None.<h4>Measurements and main results</h4>Acute respiratory distress syndrome developed in 738 (26%) patients; 413 patients (15%) received a statin within 24 hrs of intensive care unit admission. Those who had received a statin within 24 hrs had a lower rate of development of acute respiratory distress syndrome (odds ratio 0.56; 95% confidence interval 0.43-0.73; p<.0001). After multivariate adjustment for potential confounders, this association remained significant (odds ratio 0.69; 95% confidence interval 0.51-0.92; p=.01). However, after propensity score matching, the association was not statistically significant (odds ratio 0.79; 95% confidence interval 0.57-1.10; p=.16). Statin use was not associated with reduced acute respiratory distress syndrome mortality, organ dysfunction, or ventilator-free days. Results of the study were presented in accordance with STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines.<h4>Conclusions</h4>Statin therapy at the time of intensive care unit admission was not associated with a lower rate of development of acute respiratory distress syndrome after matching for patient propensity to receive statins. Statin therapy was not associated with improvements in acute respiratory distress syndrome mortality, organ failure, or days free from mechanical ventilation.
Also flagged:cancerWnttumorprostaglandincell growthAPC
Journal Article2012-05-01No SnippetsPolakis P.
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Aberrant regulation of the Wnt signaling pathway is a prevalent theme in cancer biology. From the earliest observation that Wnt overexpression could lead to malignant transformation of mouse mammary tissue to the most recent genetic discoveries gleaned from tumor genome sequencing, the Wnt pathway continues to evolve as a central mechanism in cancer biology. This article summarizes the evidence supporting a role for Wnt signaling in human cancer. This includes a review of the genetic mutations affecting Wnt pathway components, as well as some of epigenetic mechanisms that alter expression of genes relevant to Wnt. I also highlight some research on the cooperativity of Wnt with other signaling pathways in cancer. Finally, some emphasis is placed on laboratory research that provides a proof of concept for the therapeutic inhibition of Wnt signaling in cancer.
Also flagged:high-mobilityantithrombin IIIinterferon(IFNhigh-mobility group box 1HMGB1
Journal Article2012-05-01✓ 5 SnippetsKojima D, Mera T, Nishinakamura H, Itoh T, Ogata T, Matsuoka N, Kodama S, Yasunami Y.
In-Text Gene Mentions
Abstract)
…prevented by antithrombin (ATIII).<h4>Methods</h4>The effect o…
Abstract)
….<h4>Methods</h4>The effect ofATIIIon in vitro…
Abstract)
…the effect ofATIIIon amelioration of…
Abstract)
…was suppressed byATIII.…
Abstract)
…the liver whenATIIIbut not vehicle…
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<h4>Background</h4>The low efficiency of pancreatic islet transplantation mainly because of the early loss of transplanted islets hampers its clinical application. Previously, we have shown in mice that the early loss of transplanted islets in the liver is caused by innate immune rejection in concert with dendritic cells, natural killer T cells, and neutrophils to produce interferon (IFN)-γ, which is triggered by high-mobility group box 1 (HMGB1) released from transplanted islets. We herein determined whether the HMGB1-mediated early loss of transplanted mouse islets is prevented by antithrombin (ATIII).<h4>Methods</h4>The effect of ATIII on in vitro and in vivo HMGB1-stimulated IFN-γ production of hepatic mononuclear cells was examined. Then, the effect of ATIII on amelioration of hyperglycemia in streptozotocin-induced diabetic mice receiving 200 syngeneic islets from a single donor was determined.<h4>Results</h4>In vitro and in vivo IFN-γ production of mononuclear cells in the liver of mice in response to HMGB1 was suppressed by ATIII. Hyperglycemia of streptozotocin-induced diabetic mice receiving 200 syngeneic islets into the liver from a single donor was ameliorated with down-regulation of IFN-γ production of natural killer T cells and neutrophils in the liver when ATIII but not vehicle was administered once at the time of islet transplantation. The favorable effect of ATIII was similarly achieved in mice receiving islet allografts when rejection was prevented with anti-CD4 antibody treatment.<h4>Conclusions</h4>These findings demonstrate that ATIII prevents HMGB1-mediated early loss of transplanted islets caused by innate immune rejection, suggesting a potential application of ATIII to improve efficiency of clinical islet transplantation.
The Huntington's disease gene product, huntingtin, is indispensable for neural tube formation, but its role is obscure. We studied neurulation in htt-null embryonic stem cells and htt-morpholino zebrafish embryos and found a previously unknown, evolutionarily recent function for this ancient protein. We found that htt was essential for homotypic interactions between neuroepithelial cells; it permitted neurulation and rosette formation by regulating metalloprotease ADAM10 activity and Ncadherin cleavage. This function was embedded in the N terminus of htt and was phenocopied by treatment of htt knockdown zebrafish with an ADAM10 inhibitor. Notably, in htt-null cells, reversion of the rosetteless phenotype occurred only with expression of evolutionarily recent htt heterologues from deuterostome organisms. Conversely, all of the heterologues that we tested, including htt from Drosophila melanogaster and Dictyostelium discoideum, exhibited anti-apoptotic activity. Thus, anti-apoptosis may have been one of htt’s ancestral function(s), but, in deuterostomes, htt evolved to acquire a unique regulatory activity for controlling neural adhesion via ADAM10-Ncadherin, with implications for brain evolution and development.
Journal Article2012-05-01No SnippetsNyquist SK, Anderson JL, Donahue RH, Caruso E, Alore ML, Larson JS.
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This article describes the unique practice of nurse-driven titration of continuous insulin infusion in post-cardiac surgery patients in the intensive care unit at a tertiary care teaching hospital. A prospective quality assurance study was conducted to support our innovative practice.
Also flagged:idiopathic pulmonary embolismHTPEcoagulationProtein Cdeficiency
Journal Article2012-05-01✓ 5 SnippetsLee M, No HJ, Jang SY, Kim N, Choi SH, Kim H, Kim SH, Kim HJ, Kim DK.
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Introduction)
…Hereditary thrombophilia (HT) is considered a major risk factor for idiopathic VTE and its recurrence.4,5 Since the first report of a mutation in the SERPINC1 gene in a family with antithrombin (AT) deficiency, other resulting genetic defects have been identified including factor V Leiden, prothrombin G20210A mutation, protein C (PC) deficiency, protein S (PS) deficiency, and plasminogen (PLG) deficiency.…
Discussion)
…One of the two mutations in SERPINC1, Trp81X in AT-1, was a novel mutation, and the Ala620Thr mutation in PLG has been previously reported in Korean patients with DVT.28…
Introduction)
…mutation in theSERPINC1gene in a…
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…, PROS1 ,SERPINC1, and PLG…
Results)
…mutation in theSERPINC1gene, and one…
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<h4>Purpose</h4>Hereditary thrombophilia (HT) is a major risk factor for idiopathic pulmonary embolism (iPE) and shows different prevalence among ethnic groups. The prevalence and clinical characteristics of HT in Korean patients with iPE were investigated.<h4>Materials and methods</h4>Patients with PE on computed tomography (CT) scan were recruited, and those with malignancy were excluded. Patients were divided into iPE and provoked PE (pPE) groups. The presence of HT in the iPE group was assessed by DNA sequencing of the corresponding gene in patients who had low levels of natural anticoagulants. The clinical characteristics of iPE with HT (iPE/HT+) were compared with those of iPE without HT (iPE/HT-) and pPE.<h4>Results</h4>Out of 161 patients, 84 patients had iPE and 77 patients had pPE. Among 54 patients in the iPE group whose coagulation profiles were tested, 28 patients were diagnosed with HT (51.9%; 28/54). Compared with the iPE/HT- and pPE groups, the iPE/HT+ group showed the highest proportion of male patients (71.4%; p<0.001); the youngest mean age (44±14 years; p<0.001); and the highest frequencies for history of venous thromboembolism (64.3%; p<0.001), concurrent deep vein thrombosis (75.0%; p=0.021), and adverse clinical outcomes (42.9%, p<0.001). Protein C deficiency was the most common HT. On molecular genetic tests, causative mutation was identified in 13 patients.<h4>Conclusion</h4>In this study of Korean patients, about half of the patients with iPE had HT. Patients with iPE and HT were mostly young males with deep venous thrombosis (DVT), previous venous thromboembolism (VTE), and frequent adverse clinical outcomes. Therefore, Korean patients with iPE should be tested for HT.
Also flagged:obesitychildhood obesityadult obesityHOXB5Type 1 DiabetesKidney Diseases
Journal Article2012-05-01✓ 5 SnippetsBradfield JP, Taal HR, Timpson NJ, Scherag A, Lecoeur C, Warrington NM, Hypponen E, Holst C, Valcarcel B, Thiering E, Salem RM, Schumacher FR, Cousminer DL, Sleiman PM, Zhao J, Berkowitz RI, Vimaleswaran KS, Jarick I, Pennell CE, Evans DM, St Pourcain B, Berry DJ, Mook-Kanamori DO, Hofman A, Rivadeneira F, Uitterlinden AG, van Duijn CM, van der Valk RJ, de Jongste JC, Postma DS, Boomsma DI, Gauderman WJ, Hassanein MT, Lindgren CM, Mägi R, Boreham CA, Neville CE, Moreno LA, Elliott P, Pouta A, Hartikainen AL, Li M, Raitakari O, Lehtimäki T, Eriksson JG, Palotie A, Dallongeville J, Das S, Deloukas P, McMahon G, Ring SM, Kemp JP, Buxton JL, Blakemore AI, Bustamante M, Guxens M, Hirschhorn JN, Gillman MW, Kreiner-Møller E, Bisgaard H, Gilliland FD, Heinrich J, Wheeler E, Barroso I, O'Rahilly S, Meirhaeghe A, Sørensen TI, Power C, Palmer LJ, Hinney A, Widen E, Farooqi IS, McCarthy MI, Froguel P, Meyre D, Hebebrand J, Jarvelin MR, Jaddoe VW, Smith GD, Hakonarson H, Grant SF, Early Growth Genetics Consortium.
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Abstract)
…A genome-wide association meta-analysis identifies new childhood obesity loci.…
S I O 001029)
…For example, the OLFM4 gene product down regulates innate immunity against infection by the stomach bacterium, Helicobacter pylori9, with obese subjects having a higher occurrence of Helicobacter pylori infection than lean counterparts10,11; indeed, weight-loss induced by obesity surgery eradicates Helicobacter pylori12.…
S I O 001029)
…The gene encoding olfactomedin 4 (OLFM4) is the nearest gene to rs9568856 but is still approximately 500kb from the associated signal; the gene product has never been directly implicated in obesity but has been extensively studied in the context of various cancers.…
S I O 001029)
…Interestingly, in addition to OLFM4 and HOXB5, GIANT also supports an association with three more of the eight loci initially taken forward in to the replication effort, namely rs4864201 at BC041448, rs4833407 at ALPK1 and rs2300095 at MTORANGPTL7 loci, despite these signals not formally replicating in the main defined overall pediatric setting, suggesting that these loci should be followed up further to fully understand their role in the pathogenesis of obesity as a whole.…
S I O 001029)
…Although the function of OLFM4 is not well understood, there are several intriguing observations that link it to gut microflora and to a relationship between the gut microbiome and obesity risk.…
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Multiple genetic variants have been associated with adult obesity and a few with severe obesity in childhood; however, less progress has been made in establishing genetic influences on common early-onset obesity. We performed a North American, Australian and European collaborative meta-analysis of 14 studies consisting of 5,530 cases (≥95th percentile of body mass index (BMI)) and 8,318 controls (<50th percentile of BMI) of European ancestry. Taking forward the eight newly discovered signals yielding association with P < 5 × 10(-6) in nine independent data sets (2,818 cases and 4,083 controls), we observed two loci that yielded genome-wide significant combined P values near OLFM4 at 13q14 (rs9568856; P = 1.82 × 10(-9); odds ratio (OR) = 1.22) and within HOXB5 at 17q21 (rs9299; P = 3.54 × 10(-9); OR = 1.14). Both loci continued to show association when two extreme childhood obesity cohorts were included (2,214 cases and 2,674 controls). These two loci also yielded directionally consistent associations in a previous meta-analysis of adult BMI(1).
Also flagged:neuronal migrationaxonaltranscription factorsorganizationcognitive impairmentsneurological disorders
Journal Article2012-05-01No SnippetsKwan KY, Sestan N, Anton ES.
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The cerebral neocortex is segregated into six horizontal layers, each containing unique populations of molecularly and functionally distinct excitatory projection (pyramidal) neurons and inhibitory interneurons. Development of the neocortex requires the orchestrated execution of a series of crucial processes, including the migration of young neurons into appropriate positions within the nascent neocortex, and the acquisition of layer-specific neuronal identities and axonal projections. Here, we discuss emerging evidence supporting the notion that the migration and final laminar positioning of cortical neurons are also co-regulated by cell type- and layer-specific transcription factors that play concomitant roles in determining the molecular identity and axonal connectivity of these neurons. These transcriptional programs thus provide direct links between the mechanisms controlling the laminar position and identity of cortical neurons.
Also flagged:Asthmacorticosteroidsleukotriene receptortiotropiumcolchicinemacrolide
Journal Article2012-05-01No SnippetsSzefler SJ, Chinchilli VM, Israel E, Denlinger LC, Lemanske RF, Calhoun W, Peters SP, National Heart, Lung and Blood Institute Asthma Clinical Research Network.
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The National Heart, Lung and Blood Institute (NHLBI) Asthma Clinical Research Network (ACRN) recently completed its work after 20 years of collaboration as a multicentre clinical trial network. When formed, its stated mission was to perform multiple controlled clinical trials for treating patients with asthma by dispassionately examining new and existing therapies, and to rapidly communicate its findings to the medical community. The ACRN conducted 15 major clinical trials. In addition, clinical data, manual of operations, protocols and template informed consents from all ACRN trials are available via NHLBI BioLINCC (https://biolincc.nhlbi.nih.gov/studies/). This network contributed major insights into the use of inhaled corticosteroids, short-acting and long-acting ß-adrenergic agonists, leukotriene receptor antagonists, and novel agents (tiotropium, colchicine and macrolide antibiotics). They also pioneered studies of the variability in drug response, predictors of treatment response and pharmacogenetics. This review highlights the major research observations from the ACRN that have impacted the current management of asthma.
Liver enzymes, including aminotransferases and alkaline phosphatase, are some of the most commonly ordered blood tests in a physician's practice. These enzymes have been valuable in screening for liver disease, as well as in diagnosing and monitoring patients with acute and chronic hepatobiliary disorders. Patients with predominantly aminotransferase elevations are thought to have acute or chronic hepatitis from a variety of causes. In patients with predominantly alkaline phosphatase elevations, imaging evaluation is undertaken upfront to exclude large bile duct disorders and infiltrative/mass lesions. A liver biopsy may be reserved for patients for whom these less invasive investigations are unfruitful.
Also flagged:lipogenic transcription factorChREBPhepatic steatosisinsulin resistanceNonalcoholic fatty liver diseaseNAFLD
Journal Article2012-05-01✓ 1 SnippetBenhamed F, Denechaud PD, Lemoine M, Robichon C, Moldes M, Bertrand-Michel J, Ratziu V, Serfaty L, Housset C, Capeau J, Girard J, Guillou H, Postic C.
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…hemochromatosis…
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Nonalcoholic fatty liver disease (NAFLD) is associated with all features of the metabolic syndrome. Although deposition of excess triglycerides within liver cells, a hallmark of NAFLD, is associated with a loss of insulin sensitivity, it is not clear which cellular abnormality arises first. We have explored this in mice overexpressing carbohydrate responsive element-binding protein (ChREBP). On a standard diet, mice overexpressing ChREBP remained insulin sensitive, despite increased expression of genes involved in lipogenesis/fatty acid esterification and resultant hepatic steatosis (simple fatty liver). Lipidomic analysis revealed that the steatosis was associated with increased accumulation of monounsaturated fatty acids (MUFAs). In primary cultures of mouse hepatocytes, ChREBP overexpression induced expression of stearoyl-CoA desaturase 1 (Scd1), the enzyme responsible for the conversion of saturated fatty acids (SFAs) into MUFAs. SFA impairment of insulin-responsive Akt phosphorylation was therefore rescued by the elevation of Scd1 levels upon ChREBP overexpression, whereas pharmacological or shRNA-mediated reduction of Scd1 activity decreased the beneficial effect of ChREBP on Akt phosphorylation. Importantly, ChREBP-overexpressing mice fed a high-fat diet showed normal insulin levels and improved insulin signaling and glucose tolerance compared with controls, despite having greater hepatic steatosis. Finally, ChREBP expression in liver biopsies from patients with nonalcoholic steatohepatitis was increased when steatosis was greater than 50% and decreased in the presence of severe insulin resistance. Together, these results demonstrate that increased ChREBP can dissociate hepatic steatosis from insulin resistance, with beneficial effects on both glucose and lipid metabolism.
Also flagged:cysteinesbindingcysteineH-Rasdeoxypalmitoyl
Journal Article2012-05-01No SnippetsSpringstead JR, Gugiu BG, Lee S, Cha S, Watson AD, Berliner JA.
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Oxidation products of 1-palmitoyl-2-arachidonoyl-sn-glycerol-3-phosphatidylcholine (PAPC), referred to as OxPAPC, and an active component, 1-palmitoyl-2-(5,6-epoxyisoprostane E₂)-sn-glycero-3-phosphatidylcholine (PEIPC), accumulate in atherosclerotic lesions and regulate over 1,000 genes in human aortic endothelial cells (HAEC). We previously demonstrated that OxPNB, a biotinylated analog of OxPAPC, covalently binds to a number of proteins in HAEC. The goal of these studies was to gain insight into the binding mechanism and determine whether binding regulates activity. In whole cells, N-acetylcysteine inhibited gene regulation by OxPAPC, and blocking cell cysteines with N-ethylmaleimide strongly inhibited the binding of OxPNB to HAEC proteins. Using MS, we demonstrate that most of the binding of OxPAPC to cysteine is mediated by PEIPC. We also show that OxPNB and PEIPE-NB, the analog of PEIPC, bound to a model protein, H-Ras, at cysteines previously shown to regulate activity in response to 15-deoxy-Δ12,14-prostaglandin J2 (15dPGJ₂). This binding was observed with recombinant protein and in cells overexpressing H-Ras. OxPAPC and PEIPC compete with OxPNB for binding to H-Ras. 15dPGJ₂ and OxPAPC increased H-Ras activity at comparable concentrations. Using microarray analysis, we demonstrate a considerable overlap of gene regulation by OxPAPC, PEIPC, and 15dPGJ₂ in HAEC, suggesting that some effects attributed to 15dPGJ₂ may also be regulated by PEIPC because both molecules accumulate in inflammatory sites. Overall, we provide evidence for the importance of OxPAPC-cysteine interactions in regulating HAEC function.
Also flagged:acetylcholineglutamate receptorsbehavioralgroup I metabotropic glutamate receptorsmGluRsmuscarinic acetylcholine receptors
Journal Article2012-05-01No SnippetsPark JY, Spruston N.
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A variety of neurotransmitters are responsible for regulating neural activity during different behavioral states. Unique responses to combinations of neurotransmitters provide a powerful mechanism by which neural networks could be differentially activated during a broad range of behaviors. Here, we show, using whole-cell recordings in rat hippocampal slices, that group I metabotropic glutamate receptors (mGluRs) and muscarinic acetylcholine receptors (mAChRs) synergistically increase the excitability of hippocampal CA1 pyramidal neurons by converting the post-burst afterhyperpolarization to an afterdepolarization via a rapidly reversible upregulation of Ca(v)2.3 R-type calcium channels. Coactivation of mAChRs and mGluRs also induced a long-lasting enhancement of the responses mediated by each receptor type. These results suggest that cooperative signaling via mAChRs and group I mGluRs could provide a mechanism by which cognitive processes may be modulated by conjoint activation of two separate neurotransmitter systems.
Reactive astrogliosis is characterized by a profound change in astrocyte phenotype in response to all CNS injuries and diseases. To better understand the reactive astrocyte state, we used Affymetrix GeneChip arrays to profile gene expression in populations of reactive astrocytes isolated at various time points after induction using two mouse injury models, ischemic stroke and neuroinflammation. We find reactive gliosis consists of a rapid, but quickly attenuated, induction of gene expression after insult and identify induced Lcn2 and Serpina3n as strong markers of reactive astrocytes. Strikingly, reactive astrocyte phenotype strongly depended on the type of inducing injury. Although there is a core set of genes that is upregulated in reactive astrocytes from both injury models, at least 50% of the altered gene expression is specific to a given injury type. Reactive astrocytes in ischemia exhibited a molecular phenotype that suggests that they may be beneficial or protective, whereas reactive astrocytes induced by LPS exhibited a phenotype that suggests that they may be detrimental. These findings demonstrate that, despite well established commonalities, astrocyte reactive gliosis is a highly heterogeneous state in which astrocyte activities are altered to respond to the specific injury. This raises the question of how many subtypes of reactive astrocytes exist. Our findings provide transcriptome databases for two subtypes of reactive astrocytes that will be highly useful in generating new and testable hypotheses of their function, as well as for providing new markers to detect different types of reactive astrocytes in human neurological diseases.
Also flagged:waterdengueinfectionsdengue hemorrhagic feverparasitic infectionstransportation
Journal Article2012-05-01No SnippetsNam VS, Yen NT, Duc HM, Tu TC, Thang VT, Le NH, San LH, Loan LL, Huong VTQ, Khanh LHK, Trang HTT, Lam LZY, Kutcher SC, Aaskov JG, Jeffery JAL, Ryan PA, Kay BH.
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We previously reported a new community-based mosquito control strategy that resulted in elimination of Aedes aegypti (Linn.) in 40 of 46 communes in northern and central Vietnam, and with annual recurrent total costs (direct and indirect) of only $0.28-$0.89 international dollars per person. This control strategy was extended to four provinces in southern Vietnam in Long An and Hau Giang (2004-2007) and to Long An, Ben Tre, and Vinh Long (2005-2010). In a total of 14 communes with 124,743 residents, the mean ± SD of adult female Ae. aegypti was reduced from 0.93 ± 0.62 to 0.06 ± 0.09, and the reduction of immature Ae. aegypti averaged 98.8%. By the final survey, no adults could be collected in 6 of 14 communes, and one commune, Binh Thanh, also had no immature forms. Although the community-based programs also involved community education and clean-up campaigns, the prevalence of Mesocyclops in large water storage containers > 50 liters increased from 12.77 ± 8.39 to 75.69 ± 9.17% over periods of 15-45 months. At the conclusion of the study, no confirmed dengue cases were detected in four of the five communes for which diagnostic serologic analysis was performed. The rate of progress was faster in communes that were added in stages to the program but the reason for this finding was unclear. At the completion of the formal project, sustainability funds were set up to provide each commune with the financial means to ensure that community-based dengue control activities continued.
In this investigation, gene-environment interaction effects in predicting resilience in adaptive functioning among maltreated and nonmaltreated low-income children (N = 595) were examined. A multicomponent index of resilient functioning was derived and levels of resilient functioning were identified. Variants in four genes (serotonin transporter linked polymorphic region, corticotropin releasing hormone receptor 1, dopamine receptor D4-521C/T, and oxytocin receptor) were investigated. In a series of analyses of covariance, child maltreatment demonstrated a strong negative main effect on children's resilient functioning, whereas no main effects for any of the genotypes of the respective genes were found. However, gene-environment interactions involving genotypes of each of the respective genes and maltreatment status were obtained. For each respective gene, among children with a specific genotype, the relative advantage in resilient functioning of nonmaltreated compared to maltreated children was stronger than was the case for nonmaltreated and maltreated children with other genotypes of the respective gene. Across the four genes, a composite of the genotypes that more strongly differentiated resilient functioning between nonmaltreated and maltreated children provided further evidence of genetic variations influencing resilient functioning in nonmaltreated children, whereas genetic variation had a negligible effect on promoting resilience among maltreated children. Additional effects were observed for children based on the number of subtypes of maltreatment children experienced, as well as for abuse and neglect subgroups. Finally, maltreated and nonmaltreated children with high levels of resilience differed in their average number of differentiating genotypes. These results suggest that differential resilient outcomes are based on the interaction between genes and developmental experiences.
Also flagged:methylationXchromosomeimprintingdemethylationhistone modifications
Journal Article2012-05-01✓ 1 SnippetNazor KL, Altun G, Lynch C, Tran H, Harness JV, Slavin I, Garitaonandia I, Müller FJ, Wang YC, Boscolo FS, Fakunle E, Dumevska B, Lee S, Park HS, Olee T, D'Lima DD, Semechkin R, Parast MM, Galat V, Laslett AL, Schmidt U, Keirstead HS, Loring JF, Laurent LC.
In-Text Gene Mentions
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…POU3F2…
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Human pluripotent stem cells (hPSCs) are potential sources of cells for modeling disease and development, drug discovery, and regenerative medicine. However, it is important to identify factors that may impact the utility of hPSCs for these applications. In an unbiased analysis of 205 hPSC and 130 somatic samples, we identified hPSC-specific epigenetic and transcriptional aberrations in genes subject to X chromosome inactivation (XCI) and genomic imprinting, which were not corrected during directed differentiation. We also found that specific tissue types were distinguished by unique patterns of DNA hypomethylation, which were recapitulated by DNA demethylation during in vitro directed differentiation. Our results suggest that verification of baseline epigenetic status is critical for hPSC-based disease models in which the observed phenotype depends on proper XCI or imprinting and that tissue-specific DNA methylation patterns can be accurately modeled during directed differentiation of hPSCs, even in the presence of variations in XCI or imprinting.
Also flagged:cell cyclehematopoietic disordersErythroid DifferentiationTHRBPTPLAD1CDT1
Journal Article2012-05-01✓ 3 SnippetsDing K, Shameer K, Jouni H, Masys DR, Jarvik GP, Kho AN, Ritchie MD, McCarty CA, Chute CG, Manolio TA, Kullo IJ.
In-Text Gene Mentions
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…HFE…
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…TRIM38…
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<h4>Objective</h4>To identify common genetic variants influencing red blood cell (RBC) traits.<h4>Patients and methods</h4>We performed a genomewide association study from June 2008 through July 2011 of hemoglobin, hematocrit, RBC count, mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration in 12,486 patients of European ancestry from the electronic MEdical Records and Genomics (eMERGE) network. We developed an electronic medical record-based algorithm that included individuals who had RBC measurements obtained for clinical care and excluded values measured in the setting of hematopoietic disorders, comorbid conditions, or medications known to affect RBC production or a recent history of blood loss.<h4>Results</h4>We identified 4 new genetic loci and replicated 11 loci previously reported to be associated with one or more RBC traits in individuals of European ancestry. Notably, genes present in 3 of the 4 newly identified loci (THRB, PTPLAD1, CDT1) and in 6 of the 11 replicated loci (KLF1, ALDH8A1, CCND3, SPTA1, FBXO7, TFR2/EPO) are implicated in erythroid differentiation and regulation of cell cycle in hematopoietic stem cells.<h4>Conclusion</h4>Genes in the erythroid differentiation and cell cycle regulation pathways influence interindividual variation in RBC indices. Our results provide insights into the molecular basis underlying variation in RBC traits.
Also flagged:viral infectionstarchaspartate aminotransferaseASTalanine aminotransferaseALT
Journal Article2012-05-01✓ 1 SnippetHegazy SK, El-Bedewy M, Yagi A.
In-Text Gene Mentions
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…hemochromatosis…
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<h4>Aim</h4>To investigate the anti-oxidative and anti-fibrotic effects of aloe vera in patients with liver fibrosis.<h4>Methods</h4>Aloe vera high molecular weight fractions (AHM) were processed by patented hyper-dry system in combination of freeze-dry technique with microwave and far infrared-ray radiation. Fifteen healthy volunteers as the control group and 40 patients were included. The patients were randomly subdivided into two equal groups: the conventional group was treated with placebo (starch), and AHM group was treated with 0.15 gm/d AHM, both for 12 consecutive weeks. The patients were investigated before and after treatment. Serum activity of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), hyaluronic acid (HA), transforming growth factor-β (TGF-β) and matrixmetalloproteinase-2 (MMP-2) were determined. The reduced glutathione (GSH) and malondialdehyde (MDA) levels in liver were assayed and the expression of hepatic α-smooth muscle actin (α-SMA) was identified by immunohistochemistry.<h4>Results</h4>At the start of the study, the hematoxylin and eosin staining revealed fibro-proliferated bile ductules, thick fibrous septa and dense inflammatory cellular infiltration in the patients before treatment. The use of AHM for 12 wk significantly ameliorated the fibrosis, inhibited the inflammation, and resulted in minimal infiltration and minimal fibrosis compared to the conventional group. The enzyme activities of the liver (ALT, AST and ALP) were attenuated after treatment in both groups, and the decrease in the AHM group was more significant as compared with the conventional group. Similar to the AST, the MDA levels were significantly higher before treatment, and were attenuated after treatment in both groups. In contrast, the hepatic glutathione content in the patients were decreased significantly in the AHM group compared to the controls. The serum levels of the fibrosis markers (HA, TGF-β and MMP-2) were also reduced significantly after treatment. The expression of α-SMA was modified in patients before and after treatment as compared with the normal controls. In the conventional group, there was only thin and incomplete parenchymal α-SMA positive septum joining the thickened centrilobular veins, while in the AHM group, few α-SMA positive cells were present in sinusoid and lobule after treatment.<h4>Conclusion</h4>Oral supplementation with AHM could be helpful in alleviating the fibrosis and inflammation of hepatic fibrosis patients.
Also flagged:Parkinson's diseasePDneurodegenerative diseaseparaquatpyridabenmaneb
Journal Article2012-05-01✓ 1 SnippetGollamudi S, Johri A, Calingasan NY, Yang L, Elemento O, Beal MF.
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Results)
…, Plce1 andCacna1ebelong to calcium…
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Parkinson's disease (PD) is a neurodegenerative disease in which the etiology of 90 percent of the patients is unknown. Pesticide exposure is a major risk factor for PD, and paraquat (PQ), pyridaben (PY) and maneb (MN) are amongst the most widely used pesticides. We studied mRNA expression using transcriptome sequencing (RNA-Seq) in the ventral midbrain (VMB) and striatum (STR) of PQ, PY and paraquat+maneb (MNPQ) treated mice, followed by pathway analysis. We found concordance of signaling pathways between the three pesticide models in both the VMB and STR as well as concordance in these two brain areas. The concordant signaling pathways with relevance to PD pathogenesis were e.g. axonal guidance signaling, Wnt/β-catenin signaling, as well as pathways not previously linked to PD, e.g. basal cell carcinoma, human embryonic stem cell pluripotency and role of macrophages, fibroblasts and endothelial cells in rheumatoid arthritis. Human PD pathways previously identified by expression analysis, concordant with VMB pathways identified in our study were axonal guidance signaling, Wnt/β-catenin signaling, IL-6 signaling, ephrin receptor signaling, TGF-β signaling, PPAR signaling and G-protein coupled receptor signaling. Human PD pathways concordant with the STR pathways in our study were Wnt/β-catenin signaling, axonal guidance signaling and G-protein coupled receptor signaling. Peroxisome proliferator activated receptor delta (Ppard) and G-Protein Coupled Receptors (GPCRs) were common genes in VMB and STR identified by network analysis. In conclusion, the pesticides PQ, PY and MNPQ elicit common signaling pathways in the VMB and STR in mice, which are concordant with known signaling pathways identified in human PD, suggesting that these pathways contribute to the pathogenesis of idiopathic PD. The analysis of these networks and pathways may therefore lead to improved understanding of disease pathogenesis, and potential novel therapeutic targets.
Also flagged:ironchromosomemetabolismsynthesisiron disorders
Journal Article2012-05-01✓ 5 SnippetsJouanolle AM, Gérolami V, Ged C, Grandchamp B, Le Gac G, Pissard S, Rochette J, Aguilar-Martinez P.
In-Text Gene Mentions
Abstract)
…In these recommendations, homozygosity for the p.Cys282Tyr mutation with at least elevated transferrin saturation, is considered the only genotype that confirms of the diagnosis of HFE hemochromatosis; 2) in combination with the p.Cys282Tyr mutation (compound heterozygous genotypes), the p.Ser65Cys and the p.His63Asp variants may contribute to the occurrence of mild iron overload; 3) family screening is mandatory following the detection of homozygous individuals for the p.Cys282Tyr mutation.…
HFE-related hemochromatosis (HFE hemochromatosis) or type 1 hemochromatosis is an autosomal recessive disease characterized by progressive iron overload usually expressed in adulthood. The HFE gene, located on the short arm of chromosome 6 (6p21.3), encodes a protein that plays a crucial role in iron metabolism by modulating hepcidin synthesis in the liver. Homozygosity for the p.Cys282Tyr mutation accounts for nearly 80% of cases of hemochromatosis in France. Genetic testing is the key investigation to confirm the diagnosis of HFE hemochromatosis. A survey on routine practices was carried out among the eight reference laboratories of the French national network on genetic iron disorders. The main findings from this survey are as follows: 1) the p.Cys282Tyr mutation must be searched for as an initial step to establish the diagnosis of HFE hemochromatosis. This is in agreement with the recommendations of the French Health Authority (HAS) published in 2005. In these recommendations, homozygosity for the p.Cys282Tyr mutation with at least elevated transferrin saturation, is considered the only genotype that confirms of the diagnosis of HFE hemochromatosis; 2) in combination with the p.Cys282Tyr mutation (compound heterozygous genotypes), the p.Ser65Cys and the p.His63Asp variants may contribute to the occurrence of mild iron overload; 3) family screening is mandatory following the detection of homozygous individuals for the p.Cys282Tyr mutation.
Also flagged:small heat shock proteinschaperonesneurological diseasesneurological disordersSmallheat shock proteins
Journal Article2012-05-01✓ 1 SnippetBrownell SE, Becker RA, Steinman L.
In-Text Gene Mentions
S I O 001029)
…Huntington’s disease is a neurodegenerative disease caused by a poly-glutamine expansion of the huntingtin (Htt) gene (Eidelberg and Surmeier, 2011).…
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Historically, small heat shock proteins (sHSPs) have been extensively studied in the context of being intracellular molecular chaperones. However, recent studies looking at the role of sHSPs in neurological diseases have demonstrated a near universal upregulation of certain sHSPs in damaged and diseased brains. Initially, it was thought that sHSPs are pathological in these disease states because they are found in the areas of damage. However, transgenic overexpression and exogenous administration of sHSPs in various experimental disease paradigms have shown just the contrary - that sHSPs are protective, not pathological. This review examines sHSPs in neurological diseases and highlights the potential for using these neuroprotective sHSPs as novel therapeutics. It first addresses the endogenous expression of sHSPs in a variety of neurological disorders. Although many studies have examined the expression of sHSPs in neurological diseases, there are no review articles summarizing these data. Furthermore, it focuses on recent studies that have investigated the therapeutic potential of sHSPs for neurological diseases. Finally, it will explain what we think is the function of endogenous sHSPs in neurological diseases.
Also flagged:nuclear laminachromatinorganizationlamin-like proteinenvelopelocalization
Journal Article2012-05-01✓ 1 SnippetBatsios P, Peter T, Baumann O, Stick R, Meyer I, Gräf R.
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…chromatin modifiers…
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Lamins are the major components of the nuclear lamina and serve not only as a mechanical support, but are also involved in chromatin organization, epigenetic regulation, transcription and mitotic events. Despite these universal tasks, lamins have so far been found only in metazoans. Yet, recently we have identified Dictyostelium NE81 as the first lamin-like protein in a lower eukaryote. Based on the current knowledge, we draw a model for nuclear envelope organization in Dictyostelium in this Extra View and we review the experimental data that justified this classification. Furthermore we provide unpublished data underscoring the requirement of posttranslational CaaX-box processing for proper protein localization at the nuclear envelope. Sequence comparison of NE81 sequences from four Dictyostelia with bona fide lamins illustrates the evolutional relationship between these proteins. Under certain conditions these usually unicellular social amoebae congregate to form a multicellular body. We propose that the evolution of the lamin-like NE81 went along with the invention of multicellularity.
Also flagged:Huntington's diseaseHDglucoseoxygenmetabolismbehavioral
Journal Article2012-05-01✓ 1 SnippetCepeda-Prado E, Popp S, Khan U, Stefanov D, Rodríguez J, Menalled LB, Dow-Edwards D, Small SA, Moreno H.
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…htt…
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A hallmark feature of Huntington's disease pathology is the atrophy of brain regions including, but not limited to, the striatum. Though MRI studies have identified structural CNS changes in several Huntington's disease (HD) mouse models, the functional consequences of HD pathology during the progression of the disease have yet to be investigated using in vivo functional MRI (fMRI). To address this issue, we first established the structural and functional MRI phenotype of juvenile HD mouse model R6/2 at early and advanced stages of disease. Significantly higher fMRI signals [relative cerebral blood volumes (rCBVs)] and atrophy were observed in both age groups in specific brain regions. Next, fMRI results were correlated with electrophysiological analysis, which showed abnormal increases in neuronal activity in affected brain regions, thus identifying a mechanism accounting for the abnormal fMRI findings. [(14)C] 2-deoxyglucose maps to investigate patterns of glucose utilization were also generated. An interesting mismatch between increases in rCBV and decreases in glucose uptake was observed. Finally, we evaluated the sensitivity of this mouse line to audiogenic seizures early in the disease course. We found that R6/2 mice had an increased susceptibility to develop seizures. Together, these findings identified seizure activity in R6/2 mice and show that neuroimaging measures sensitive to oxygen metabolism can be used as in vivo biomarkers, preceding the onset of an overt behavioral phenotype. Since fMRI-rCBV can also be obtained in patients, we propose that it may serve as a translational tool to evaluate therapeutic responses in humans and HD mouse models.
Also flagged:synaptosomesgp120-associated neurocognitive disordersHANDsynapsesphosphotidylinositol 3-kinase
Journal Article2012-05-01No SnippetsBanerjee S, Liao L, Russo R, Nakamura T, McKercher SR, Okamoto S, Haun F, Nikzad R, Zaidi R, Holland E, Eroshkin A, Yates JR, Lipton SA.
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HIV/gp120 transgenic mice manifest neuropathological features similar to HIV-associated neurocognitive disorders (HAND) in humans, including astrogliosis, microglia activation, and decreased neuronal synapses. Here, proteomic screening of synaptosomes from HIV/gp120 transgenic mice was conducted to determine potential neuronal markers and drug targets associated with HAND. Synaptosomes from 13 month-old wild-type (wt) and HIV/gp120 transgenic mouse cortex were subjected to tandem mass tag (TMT) labeling and subsequent analysis using an LTQ-Orbitrap mass spectrometer in pulsed-Q dissociation (PQD) mode for tandem mass spectrometry (MS/MS). A total of 1301 proteins were identified in both wt and HIV/gp120 transgenic mice. Three of the most differentially-regulated proteins were validated by immunoblotting. To elucidate putative pathways associated with the proteomic profile, 107 proteins manifesting a ≥1.5 fold change in expression were analyzed using a bioinformatics pathway analysis tool. This analysis revealed direct or indirect involvement of the phosphotidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway, a well-known neuronal survival pathway. Immunoblots confirmed a lower phospho (p)Akt/Akt ratio in synaptosomes from HIV/gp120 transgenic animals compared to wt, suggesting that this neuroprotective pathway was inactivated in the HIV/gp120 transgenic brain. Based on this information, we then compared immunoblots of pAkt/Akt in the forebrains of these mice as well as in human postmortem brain. We observed a significant decrease in the pAkt/Akt ratio in synaptosomes and forebrain of HIV/gp120 transgenic compared to wt mice, and a similar decrease in human forebrain from HAND patients compared to neurologically unimpaired HIV+ and HIV- controls. Moreover, mechanistic insight into an additional pathway for decreased Akt activity in HIV/gp120 mouse brains and human HAND brains was shown to occur via S-nitrosylation of Akt protein, a posttranslational modification known to inhibit Akt activity and contribute to neuronal cell injury and death. Thus, MS proteomic profiling in the HIV/gp120 transgenic mouse predicted dysregulation of the PI3K/Akt pathway observed in human brains with HAND, providing evidence that this mouse is a useful disease model and that the Akt pathway may provide multiple drug targets for the treatment of HIV-related dementias.
Also flagged:protein synthesisdendritesaxonslocalizationgene expressionaxonal
Journal Article2012-05-01✓ 1 SnippetCajigas IJ, Tushev G, Will TJ, tom Dieck S, Fuerst N, Schuman EM.
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In neurons, dendritic protein synthesis is required for many forms of long-term synaptic plasticity. The population of mRNAs that are localized to dendrites, however, remains sparsely identified. Here, we use deep sequencing to identify the mRNAs resident in the synaptic neuropil in the hippocampus. Analysis of a neuropil data set yielded a list of 8,379 transcripts of which 2,550 are localized in dendrites and/or axons. Using a fluorescent barcode strategy to label individual mRNAs, we show that their relative abundance in the neuropil varies over 3 orders of magnitude. High-resolution in situ hybridization validated the presence of mRNAs in both cultured neurons and hippocampal slices. Among the many mRNAs identified, we observed a large fraction of known synaptic proteins including signaling molecules, scaffolds and receptors. These results reveal a previously unappreciated enormous potential for the local protein synthesis machinery to supply, maintain and modify the dendritic and synaptic proteome.
…sequences of humanhemochromatosisprotein gene, also…
I A O 0000613)
…also known asHFEgenes (Cys282Tyr and…
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CD30+ T-cell lymphoproliferative disorders (LD) comprise two main groups of diseases: CD30+ LD of the skin and systemic anaplastic large cell lymphoma (ALCL). The main feature of these disorders is the expression of CD30. We present a patient with an unusual clinical presentation of CD30+ lymphoproliferative disease in a 54-year old Caucasian male who presented with generalized lymphadenopathy and pronounced skin hyperpigmentation. In the lymph nodes and skin, CD30+ lymphoproliferation (ALCL) was diagnosed. The Prussian blue staining identified that the pigment responsible for the skin color was hemosiderin. Chemotherapy was started but the patient's condition progressively worsened and he died a week after the first cycle. The complete color transformation of the entire skin due to hemosiderin accumulation is, to the best of our knowledge, the first reported observation in a CD30+ lymphoproliferation/ALCL patient. We speculate that hemosiderin-loaded macrophages resulted from the paraneoplastic process by some still unknown mechanism.
Also flagged:Salmonellosisinfectionsinfectionhost cell-localizationbinding
Journal Article2012-05-01No SnippetsSchleker S, Garcia-Garcia J, Klein-Seetharaman J, Oliva B.
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Salmonellosis caused by Salmonella bacteria is a food-borne disease and a worldwide health threat causing millions of infections and thousands of deaths every year. This pathogen infects an unusually broad range of host organisms including human and plants. A better understanding of the mechanisms of communication between Salmonella and its hosts requires identifying the interactions between Salmonella and host proteins. Protein-protein interactions (PPIs) are the fundamental building blocks of communication. Here, we utilize the prediction platform BIANA to obtain the putative Salmonella-human and Salmonella-Arabidopsis interactomes based on sequence and domain similarity to known PPIs. A gold standard list of Salmonella-host PPIs served to validate the quality of the human model. 24,726 and 10,926 PPIs comprising interactions between 38 and 33 Salmonella effectors and virulence factors with 9,740 human and 4,676 Arabidopsis proteins, respectively, were predicted. Putative hub proteins could be identified, and parallels between the two interactomes were discovered. This approach can provide insight into possible biological functions of so far uncharacterized proteins. The predicted interactions are available via a web interface which allows filtering of the database according to parameters provided by the user to narrow down the list of suspected interactions. The interactions are available via a web interface at http://sbi.imim.es/web/SHIPREC.php.
Journal Article2012-05-01No SnippetsRuppen-Cañás I, López-Casas PP, García F, Ximénez-Embún P, Muñoz M, Morelli MP, Real FX, Serna A, Hidalgo M, Ashman K.
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New disease specific biomarkers, especially for cancer, are urgently needed to improve individual diagnosis, prognosis, and treatment selection, that is, for personalized medicine. Genetic mutations that affect protein function drive cancer. Therefore, the detection of such mutations represents a source of cancer specific biomarkers. Here we confirm the implementation of the mutant protein specific immuno-SRM (where SRM is selective reaction monitoring) mass spectrometry method of RAS proteins reported by Wang et al. [Proc. Natl. Acad. Sci. USA 2011, 108, 2444-2449], which exploits an antibody to simultaneously capture the different forms of the target protein and the resolving power and sensitivity of LC-MS/MS and improve the technique by using a more sensitive mass spectrometer. The mutant form G12D was quantified by SRM on a QTRAP 5500 mass spectrometer and the MIDAS workflow was used to confirm the sequence of the targeted peptides. This assay has been applied to quantify wild type and mutant RAS proteins in patient tumors, xenografted human tissue, and benign human epidermal tumors at high sensitivity. The limit of detection for the target proteins was as low as 12 amol (0.25 pg). It requires low starting amounts of tissue (ca.15 mg) that could be obtained from a needle aspiration biopsy. The described strategy could find application in the clinical arena and be applied to the study of expression of protein variants in disease.
Also flagged:post-translational modificationsperoxiredoxin 6peroxiredoxinglutathione peroxidasephospholipase A2obesity
Journal Article2012-05-01✓ 5 SnippetsJeong J, Kim Y, Kyung Seong J, Lee KJ.
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Abstract)
…Comprehensive analysis of these PTMs revealed that the PRDX6 exists as a heterogeneous mixture of molecules containing a multitude of PTMs.…
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…PRDX6 obtained from liver tissues from two inbred mouse strains, C57BL/6J and C3H/HeJ, which vary in their susceptibility to high-fat diet-induced obesity and atherosclerosis…
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…PRDX6 obtained from liver tissues from two inbred mouse strains, C57BL/6J and C3H/HeJ, which vary in their susceptibility to high-fat diet-induced obesity…
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…PRDX6 obtained from liver tissues from two inbred mouse strains, C57BL/6J and C3H/HeJ, which vary in their susceptibility to high-fat diet-induced obesity and atherosclerosis, and a B16F10 melanoma…
Abstract)
…PRDX6 from mouse liver tissues included, among others, mono…
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Peroxiredoxin 6 (PRDX6), a 1-Cys peroxiredoxin, is a bifunctional enzyme acting both as a glutathione peroxidase and a phospholipase A2. However, the underlying mechanisms and their regulation mechanisms are not well understood. Because post-translational modifications (PTMs) have been shown to play important roles in the function of many proteins, we undertook, in this study, to identify the PTMs in PRDX6 utilizing proteomic tools including nanoUPLC-ESI-q-TOF MS/MS employing selectively excluded mass screening analysis (SEMSA) in conjunction with MOD(i) and MODmap algorithm. We chose PRDX6 obtained from liver tissues from two inbred mouse strains, C57BL/6J and C3H/HeJ, which vary in their susceptibility to high-fat diet-induced obesity and atherosclerosis, and a B16F10 melanoma cell line for this study. When PRDX6 protein samples were separated on 2D-PAGE based on pI, several PRDX6 spots appeared. They were purified and the low abundant PTMs in each PRDX6 spot were analyzed. Unexpected mass shifts (Δm = -34, +25, +64, +87, +103, +134, +150, +284 Da) observed at active site cysteine residue (Cys47) were quantified using precursor ion intensities. Mass differences of -34, +25, and +64 Da are presumed to reflect the conversion of cysteine to dehydroalanine, cyano, and Cys-SO(2) -SH, respectively. We also detected acrylamide adducts of sulfenic and sulfinic acids (+87 and +103 Da) as well as unknown modifications (+134, +150, +284 Da). Comprehensive analysis of these PTMs revealed that the PRDX6 exists as a heterogeneous mixture of molecules containing a multitude of PTMs. Several of these modifications occur at cysteine residue in the enzyme active site. Other modifications observed, in PRDX6 from mouse liver tissues included, among others, mono- and dioxidation at Trp and Met, acetylation at Lys, and deamidation at Asn and Gln. Comprehensive identification of the diverse PTMs occurring in this bifunctional PRDX6 enzyme should help understand how PRDX6 plays key roles in oxidative stresses.
Also flagged:Metforminobesitycancerbiguanidesagingtumor
Journal Article2012-05-01✓ 1 SnippetBerstein LM.
In-Text Gene Mentions
S I O 001029)
…On the other hand, bearing of one of the polymorphisms of the neuron growth regulator NEGR1 predicts the magnitude of the weight-reducing effect of metformin and, ironically, the propensity to restore body weight after the discontinuation of treatment with metformin [27].…
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Metformin, an oral anti-diabetic drug, is being considered increasingly for treatment and prevention of cancer, obesity as well as for the extension of healthy lifespan. Gradually accumulating discrepancies about its effect on cancer and obesity can be explained by the shortage of randomized clinical trials, differences between control groups (reference points), gender- and age-associated effects and pharmacogenetic factors. Studies of the potential antiaging effects of antidiabetic biguanides, such as metformin, are still experimental for obvious reasons and their results are currently ambiguous. Here we discuss whether the discrepancies in different studies are merely methodological or inherently related to individual differences in responsiveness to the drug.
Also flagged:Histone deacetylaseHDACHDAC3HDAC1polyglutamineHuntington's disease
Journal Article2012-05-01✓ 2 SnippetsJia H, Pallos J, Jacques V, Lau A, Tang B, Cooper A, Syed A, Purcell J, Chen Y, Sharma S, Sangrey GR, Darnell SB, Plasterer H, Sadri-Vakili G, Gottesfeld JM, Thompson LM, Rusche JR, Marsh JL, Thomas EA.
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Abstract)
…inhibitors to improveHtt-elicited metabolic deficits c…
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…HTT…
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We have previously demonstrated amelioration of Huntington's disease (HD)-related phenotypes in R6/2 transgenic mice in response to treatment with the novel histone deacetylase (HDAC) inhibitor 4b. Here we have measured the selectivity profiles of 4b and related compounds against class I and class II HDACs and have tested their ability to restore altered expression of genes related to HD pathology in mice and to rescue disease effects in cell culture and Drosophila models of HD. R6/2 transgenic and wild-type (wt) mice received daily injections of HDAC inhibitors for 3 days followed by real-time PCR analysis to detect expression differences for 13 HD-related genes. We find that HDACi 4b and 136, two compounds showing high potency for inhibiting HDAC3 were most effective in reversing the expression of genes relevant to HD, including Ppp1r1b, which encodes DARPP-32, a marker for medium spiny striatal neurons. In contrast, compounds targeting HDAC1 were less effective at correcting gene expression abnormalities in R6/2 transgenic mice, but did cause significant increases in the expression of selected genes. An additional panel of 4b-related compounds was tested in a Drosophila model of HD and in STHdhQ111 striatal cells to further distinguish HDAC selectivity. Significant improvement in huntingtin-elicited Drosophila eye neurodegeneration in the fly was observed in response to treatment with compounds targeting human HDAC1 and/or HDAC3. In STHdhQ111 striatal cells, the ability of HDAC inhibitors to improve huntingtin-elicited metabolic deficits correlated with the potency at inhibiting HDAC1 and HDAC3, although the IC50 values for HDAC1 inhibition were typically 10-fold higher than for inhibition of HDAC3. Assessment of HDAC protein localization in brain tissue by Western blot analysis revealed accumulation of HDAC1 and HDAC3 in the nucleus of HD transgenic mice compared to wt mice, with a concurrent decrease in cytoplasmic localization, suggesting that these HDACs contribute to a repressive chromatin environment in HD. No differences were detected in the localization of HDAC2, HDAC4 or HDAC7. These results suggest that inhibition of HDACs 1 and 3 can relieve HD-like phenotypes in model systems and that HDAC inhibitors targeting these isotypes might show therapeutic benefit in human HD.
Also flagged:Mantle cell lymphoma-like lymphomasMantle cell lymphomalymphoproliferative B-cell disordergene expressioncyclin-D1p53
Journal Article2012-05-01No SnippetsRouaud P, Fiancette R, Vincent-Fabert C, Magnone V, Cogné M, Dubus P, Denizot Y.
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Mantle cell lymphoma (MCL) is a malignant lymphoproliferative B-cell disorder that does not occur spontaneously in mice but experimental mice model have been developed. Recently two different mice models prone to develop MCL-like lymphomas were generated: c-myc-3'RR/Cdk4(R24C) mice and c-myc-3'RR/p53+/- mice. Comparison of their gene expression profiles does not highlight specific differences other than those in relation with their specific mutational status (i.e., Cdk4(R24C) mutation or p53 mutations). We propose that similarly to typical human MCL and its blastoid or cyclin-D1 variants that correspond to the same genetic entity, MCL-like lymphomas of c-myc-3'RR/ p53+/- mice and c-myc-3'RR/Cdk4(R24C) mice represent a spectrum of the same entity.
Also flagged:NMDARtranscriptional coactivatorneurodegenerative disordersHuntington's DiseaseHDHuntingtin
Journal Article2012-05-01✓ 2 SnippetsPuddifoot C, Martel MA, Soriano FX, Camacho A, Vidal-Puig A, Wyllie DJ, Hardingham GE.
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Abstract)
…compared with wild-typeHtt(18Q), and increased…
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…Htt…
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Underexpression of the transcriptional coactivator PGC-1α is causally linked to certain neurodegenerative disorders, including Huntington's Disease (HD). HD pathoprogression is also associated with aberrant NMDAR activity, in particular an imbalance between synaptic versus extrasynaptic (NMDAR(EX)) activity. Here we show that PGC-1α controls NMDAR(EX) activity in neurons and that its suppression contributes to mutant Huntingtin (mHtt)-induced increases in NMDAR(EX) activity and vulnerability to excitotoxic insults. We found that knock-down of endogenous PGC-1α increased NMDAR(EX) activity and vulnerability to excitotoxic insults in rat cortical neurons. In contrast, exogenous expression of PGC-1α resulted in a neuroprotective reduction of NMDAR(EX) currents without affecting synaptic NMDAR activity. Since HD models are associated with mHtt-mediated suppression of PGC-1α expression, as well as increased NMDAR(EX) activity, we investigated whether these two events were linked. Expression of mHtt (148Q) resulted in a selective increase in NMDAR(EX) activity, compared with wild-type Htt (18Q), and increased vulnerability to NMDA excitotoxicity. Importantly, we observed that the effects of mHtt and PGC-1α knockdown on NMDAR(EX) activity and vulnerability to excitotoxicity were nonadditive and occluded each other, consistent with a common mechanism. Moreover, exogenous expression of PGC-1α reversed mtHtt-mediated increases in NMDAR(EX) activity and protected neurons against excitotoxic cell death. The link between mHtt, PGC-1α, and NMDAR activity was also confirmed in rat striatal neurons. Thus, targeting levels of PGC-1α expression may help reduce aberrant NMDAR(EX) activity in disorders where PGC-1α is underexpressed.
Also flagged:chondrocyte differentiationcollagen XchondrogenesisbindingluciferaseFoxA2
Journal Article2012-05-01✓ 1 SnippetIonescu A, Kozhemyakina E, Nicolae C, Kaestner KH, Olsen BR, Lassar AB.
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…Sox6…
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During endochondral ossification, small, immature chondrocytes enlarge to form hypertrophic chondrocytes, which express collagen X. In this work, we demonstrate that FoxA factors are induced during chondrogenesis, bind to conserved binding sites in the collagen X enhancer, and can promote the expression of a collagen X-luciferase reporter in both chondrocytes and fibroblasts. In addition, we demonstrate by both gain- and loss-of-function analyses that FoxA factors play a crucial role in driving the expression of both endogenous collagen X and other hypertrophic chondrocyte-specific genes. Mice engineered to lack expression of both FoxA2 and FoxA3 in their chondrocytes display defects in chondrocyte hypertrophy, alkaline phosphatase expression, and mineralization in their sternebrae and, in addition, exhibit postnatal dwarfism that is coupled to significantly decreased expression of both collagen X and MMP13 in their growth plates. Our findings indicate that FoxA family members are crucial regulators of the hypertrophic chondrocyte differentiation program.
Also flagged:organizationaxon terminalsaxon guidance moleculessynaptic transmissiondevelopmental cognitive disordersgene expression
Journal Article2012-05-01No SnippetsErzurumlu RS, Gaspar P.
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In primary sensory neocortical areas of mammals, the distribution of sensory receptors is mapped with topographic precision and amplification in proportion to the peripheral receptor density. The visual, somatosensory and auditory cortical maps are established during a critical period in development. Throughout this window in time, the developing cortical maps are vulnerable to deleterious effects of sense organ damage or sensory deprivation. The rodent barrel cortex offers an invaluable model system with which to investigate the mechanisms underlying the formation of topographic maps and their plasticity during development. Five rows of mystacial vibrissa (whisker) follicles on the snout and an array of sinus hairs are represented by layer IV neural modules ('barrels') and thalamocortical axon terminals in the primary somatosensory cortex. Perinatal damage to the whiskers or the sensory nerve innervating them irreversibly alters the structural organization of the barrels. Earlier studies emphasized the role of the sensory periphery in dictating whisker-specific brain maps and patterns. Recent advances in molecular genetics and analyses of genetically altered mice allow new insights into neural pattern formation in the neocortex and the mechanisms underlying critical period plasticity. Here, we review the development and patterning of the barrel cortex and the critical period plasticity.
Also flagged:organizationaxonsserotonin5-hydroxytryptamine-synthesis
Journal Article2012-05-01No Snippetsvan Kleef ES, Gaspar P, Bonnin A.
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The topographic organization of the thalamocortical axons (TCAs) in the barrel field (BF) in the rodent primary somatosensory cortex results from a succession of temporally and spatially precise developmental events. Prenatally, growth and guidance mechanisms enable TCAs to navigate through the forebrain and reach the cortex. Postnatally, TCAs grow into the cortex, and the refinement of their terminal arborization pattern in layer IV creates barrel-like structures. The combined results of studies performed over the past 20 years clearly show that serotonin (5-hydroxytryptamine; 5-HT) signaling modulates these pre- and early postnatal developmental processes. In this context, 5-HT signaling can purposely be described as 'modulating' rather than 'controlling' because developmental alterations of 5-HT synthesis, uptake or degradation either have a dramatic, moderate or no effect at all on TCA pathway and BF formation. In this review we summarize and compare the outcomes of diverse pharmacological and genetic manipulations of 5-HT signaling on TCA pathway and BF formation, in an attempt to understand these discrepancies.
Thalamocortical axons must cross a complex cellular terrain through the developing forebrain, and this terrain has to be understood for us to learn how thalamocortical axons reach their destinations. Selective fasciculation, guidepost cells and various diencephalic and telencephalic gradients have been implicated in thalamocortical guidance. As our understanding of the relevant forebrain patterns has increased, so has our knowledge of the guidance mechanisms. Our aim here is to review recent observations of cellular and molecular mechanisms related to: the growth of thalamofugal projections to the ventral telencephalon, thalamic axon avoidance of the hypothalamus and extension into the telencephalon to form the internal capsule, the crossing of the pallial-subpallial boundary, and the growth towards the cerebral cortex. We shall review current theories for the explanation of the maintenance and alteration of topographic order in the thalamocortical projections to the cortex. It is now increasingly clear that several mechanisms are involved at different stages of thalamocortical development, and each contributes substantially to the eventual outcome. Revealing the molecular and cellular mechanisms can help to link specific genes to details of actual developmental mechanisms.
Also flagged:Golgicell migrationsignal transductionmetastatic cancerGolgi apparatusorganelle
Journal Article2012-05-01No SnippetsMillarte V, Farhan H.
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Migration and invasion are fundamental features of metastatic cancer cells. The Golgi apparatus, an organelle involved in posttranslational modification and sorting of proteins, is widely accepted to regulate directional cell migration. In addition, mounting evidence suggests that the Golgi is a hub for different signaling pathways. In this paper we will give an overview on how polarized secretion and microtubule nucleation at the Golgi regulate directional cell migration. We will review different signaling pathways that signal to and from the Golgi. Finally, we will discuss how these signaling pathways regulate the role of the Golgi in cell migration and invasion. We propose that by identifying regulators of the Golgi, we might be able to uncover unappreciated modulators of cell migration. Uncovering the regulatory network that orchestrates cell migration is of fundamental importance for the development of new therapeutic strategies against cancer cell metastasis.
Also flagged:Semaphorin6DPlexin-A1Nr-CAMvisionPlexin-A1 receptorsaxon
Journal Article2012-05-01✓ 1 SnippetKuwajima T, Yoshida Y, Takegahara N, Petros TJ, Kumanogoh A, Jessell TM, Sakurai T, Mason C.
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…DCC…
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At the optic chiasm, retinal ganglion cells (RGCs) project ipsi- or contralaterally to establish the circuitry for binocular vision. Ipsilateral guidance programs have been characterized, but contralateral guidance programs are not well understood. Here, we identify a tripartite molecular system for contralateral RGC projections: Semaphorin6D (Sema6D) and Nr-CAM are expressed on midline radial glia and Plexin-A1 on chiasm neurons, and Plexin-A1 and Nr-CAM are also expressed on contralateral RGCs. Sema6D is repulsive to contralateral RGCs, but Sema6D in combination with Nr-CAM and Plexin-A1 converts repulsion to growth promotion. Nr-CAM functions as a receptor for Sema6D. Sema6D, Plexin-A1, and Nr-CAM are all required for efficient RGC decussation at the optic chiasm. These findings suggest a mechanism by which a complex of Sema6D, Nr-CAM, and Plexin-A1 at the chiasm midline alters the sign of Sema6D and signals Nr-CAM/Plexin-A1 receptors on RGCs to implement the contralateral RGC projection.
Activity-dependent gene expression triggered by Ca(2+) entry into neurons is critical for learning and memory, but whether specific sources of Ca(2+) act distinctly or merely supply Ca(2+) to a common pool remains uncertain. Here, we report that both signaling modes coexist and pertain to Ca(V)1 and Ca(V)2 channels, respectively, coupling membrane depolarization to CREB phosphorylation and gene expression. Ca(V)1 channels are advantaged in their voltage-dependent gating and use nanodomain Ca(2+) to drive local CaMKII aggregation and trigger communication with the nucleus. In contrast, Ca(V)2 channels must elevate [Ca(2+)](i) microns away and promote CaMKII aggregation at Ca(V)1 channels. Consequently, Ca(V)2 channels are ~10-fold less effective in signaling to the nucleus than are Ca(V)1 channels for the same bulk [Ca(2+)](i) increase. Furthermore, Ca(V)2-mediated Ca(2+) rises are preferentially curbed by uptake into the endoplasmic reticulum and mitochondria. This source-biased buffering limits the spatial spread of Ca(2+), further attenuating Ca(V)2-mediated gene expression.
Also flagged:FVvenous thromboembolismpolymeraseblood coagulationFactor Vglycoprotein
Journal Article2012-05-01No SnippetsAdler G, Clark JS, Loniewska B, Czerska E, Salkic NN, Ciechanowicz A.
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The 1691G>A FV variant has been described as a common genetic risk factor in venous thromboembolism. The purpose of this study was to provide a further frequency value for 1691G>A FV in Poland and to collate summary data from Central (Poland, Czech, Slovakia), Eastern (Russia, Belarus, Ukraine) and South-Eastern (Slovenia, Croatia, Bosnia and Herzegovina, Serbia, Montenegro, Macedonia, Bulgaria) European countries. For this purpose in 2007 the 1691G>A FV variant was analyzed by polymerase chain reaction-restriction fragment length polymorphism from DNA collected in 2005-2006. We studied 650 subjects: 400 newborns and 250 older individuals (mean age 46.1 y) from Poland and compared results with reports from other countries, as well as with the frequency trend of 845G>A HFE across South-Eastern European countries using centroid cities. From our 1691G>A FV study we identified 626 GG homozygotes, 23 GA heterozygotes, and 1 AA homozygote (n = 650), giving an A allele frequency of 1.9%, and a summed frequency value for Poland of 2.0% (n = 1588); the frequency in Central European countries was 3.9% (n = 4559), mostly due to the high value in the Czech Republic: 5.1% (n = 2819); the South-Eastern European countries had 2.5% (n = 2410). Among the Eastern European countries the 1691G>A FV allele frequency was 1.9% (n=791), between the South-Eastern and Eastern European countries there was no significant difference (p=0.17). We confirm that the 1691G>A FV allele frequency in Poland, as well as other countries compared, is significantly lower than that in Czech.
Also flagged:Caspase-6Huntington's diseaseHDglutamineProteolysisamino acid
Journal Article2012-05-01✓ 5 SnippetsGafni J, Papanikolaou T, Degiacomo F, Holcomb J, Chen S, Menalled L, Kudwa A, Fitzpatrick J, Miller S, Ramboz S, Tuunanen PI, Lehtimäki KK, Yang XW, Park L, Kwak S, Howland D, Park H, Ellerby LM.
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Abstract)
…In particular, it has been postulated that proteolysis of Htt at the putative caspase-6 cleavage site (at amino acid Asp-586) plays a critical role in disease progression and pathogenesis.…
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…Proteolysis of Htt has been identified as a critical pathological event in HD models.…
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…Huntington's disease (HD) is caused by a mutation in the huntingtin (htt) gene encoding an expansion of glutamine repeats at the N terminus of the Htt protein.…
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…Importantly, we detected the presence of Htt fragments consistent with cleavage at amino acid Asp-586 of Htt in the BACHD Casp6(-/-) mouse, indicating that caspase-6 activity cannot fully account for the generation of the Htt 586 fragment in vivo.…
Abstract)
…terminus of theHttprotein.…
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Huntington's disease (HD) is caused by a mutation in the huntingtin (htt) gene encoding an expansion of glutamine repeats at the N terminus of the Htt protein. Proteolysis of Htt has been identified as a critical pathological event in HD models. In particular, it has been postulated that proteolysis of Htt at the putative caspase-6 cleavage site (at amino acid Asp-586) plays a critical role in disease progression and pathogenesis. However, whether caspase-6 is indeed the essential enzyme that cleaves Htt at this site in vivo has not been determined. To evaluate, we crossed the BACHD mouse model with a caspase-6 knock-out mouse (Casp6(-/-)). Western blot and immunocytochemistry confirmed the lack of caspase-6 protein in Casp6(-/-) mice, regardless of HD genotype. We predicted the Casp6(-/-) mouse would have reduced levels of caspase-6 Htt fragments and increased levels of full-length Htt protein. In contrast, we found a significant reduction of full-length mutant Htt (mHtt) and fragments in the striatum of BACHD Casp6(-/-) mice. Importantly, we detected the presence of Htt fragments consistent with cleavage at amino acid Asp-586 of Htt in the BACHD Casp6(-/-) mouse, indicating that caspase-6 activity cannot fully account for the generation of the Htt 586 fragment in vivo. Our data are not consistent with the hypothesis that caspase-6 activity is critical in generating a potentially toxic 586 aa Htt fragment in vivo. However, our studies do suggest a role for caspase-6 activity in clearance pathways for mHtt protein.
Also flagged:protein tyrosine phosphatase nonreceptor type 5psychopathologypsychiatric disordersPTPN5STEPextracellular signal-regulated kinase
Journal Article2012-05-01No SnippetsYang CH, Huang CC, Hsu KS.
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While stressful life events confer increased risk for the development of psychopathology, most individuals experiencing adversity maintain normal psychological functioning, suggesting that individual differences may influence the susceptibility to develop stress-related psychiatric disorders. However, little is known about what determines this difference between individuals at the molecular level. In the present study, we identify that protein tyrosine phosphatase nonreceptor type 5 (PTPN5) (also known as STEP) is a critical determinant of differences in individual susceptibility to develop stress-related cognitive and morphological changes in rats. Our data demonstrate that ablation of PTPN5 expression delays physiological recovery from stress and augments the development of stress-related cognitive and morphological changes, whereas overexpression of a constitutively active variant of PTPN5 enhances the individual's resilience to stress. Our data also reveal that reduced PTPN5 expression prolongs the duration of extracellular signal-regulated kinase activation, leading to an elevation of Ca(V)1.2 channel expression and a recovery delay of K(V)4.2 channels from inactivation, which in turn heightens neuronal vulnerability to glutamate toxicity. Moreover, intraperitoneal injections of L-type Ca(2+) channel blocker nifedipine after stress resulted in a significantly lower rate for developing stress-related cognitive and morphological changes seen in PTPN5 knockdown rats. Together, these results identify a novel role for PTPN5 in mediating the development of stress-related cognitive and morphological changes and suggest that people with PTPN5 deficiency may have a greater susceptibility to capture the deleterious effects of stress.
Also flagged:deathcaspaseoftissue homeostasismitosisproteases
Journal Article2012-05-01✓ 5 SnippetsFavaloro B, Allocati N, Graziano V, Di Ilio C, De Laurenzi V.
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Introduction)
…HD is an autosomal dominant disease caused by a mutation in the gene encoding the huntingtin protein (htt); this mutation is responsible for abnormal expansion of a trinucleotide CAG repeat encoding polyglutamine tract expansion in the N terminus of htt [64].…
Introduction)
…Mutant htt is cleaved by different proteases including caspases [67] and accumulation of caspase cleaved fragments is an early pathological finding in brains of HD patients [68].…
Introduction)
…the huntingtin protein (htt); this mutation is…
Introduction)
…N terminus ofhtt[ 64 ].…
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…Mutanthttis cleaved by…
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Since the initial description of apoptosis, a number of different forms of cell death have been described. In this review we will focus on classic caspase-dependent apoptosis and its variations that contribute to diseases. Over fifty years of research have clarified molecular mechanisms involved in apoptotic signaling as well and shown that alterations of these pathways lead to human diseases. Indeed both reduced and increased apoptosis can result in pathology. More recently these findings have led to the development of therapeutic approaches based on regulation of apoptosis, some of which are in clinical trials or have entered medical practice.
Also flagged:neonatal hemochromatosisfetal alloimmune hepatitishereditary hemochromatosisIgG
Journal Article2012-05-01✓ 1 SnippetCostaguta A, Alvarez F.
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…model of neonatalhemochromatosiswas based on…
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The classical model of neonatal hemochromatosis was based on the analogy with hereditary hemochromatosis. Medical treatment consisted on the antioxidant-chelator cocktail. The new hypothesis of an alloimmune origin of the process by which the pregnant woman mounts an IgG-based destructive response against fetal hepatocytes offers a pathogenic explanation, allowing treatment to be focused on the immunological aspects, with excellent results, and opens the possibility of preventive treatment in future pregnancies. This new paradigm produces a deep impact in diagnosis, prognosis and treatment of the disease, that should be called "fetal alloimmune hepatitis".
Also flagged:hypobetalipoproteinemiaFamilial hypobetalipoproteinemiaFHBLgenetic disorderlipidmetabolism
Journal Article2012-05-01✓ 2 SnippetsLam MC, Singham J, Hegele RA, Riazy M, Hiob MA, Francis G, Steinbrecher UP.
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I A O 0000613)
…mutation in theHFEgene for hemochromatosis.…
I A O 0000613)
…HFE gene forhemochromatosis.…
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Familial hypobetalipoproteinemia (FHBL) is a rare genetic disorder of lipid metabolism that is associated with abnormally low serum levels of low-density lipoprotein (LDL) cholesterol and apolipoprotein B. It is an autosomal co-dominant disorder, and depending on zygosity, the clinical manifestations may vary from none to neurological, endocrine, hematological or liver dysfunction. Nonalcoholic fatty liver disease is common in persons with FHBL, however progression to nonalcoholic steatohepatitis is unusual. We describe here a patient with a novel APOB mutation, V703I, which appears to contribute to the severity of the FHBL phenotype. He had liver enzyme abnormalities, increased echogenicity of the liver consistent with steatosis, very low LDL cholesterol at 0.24 mmol/l (normal 1.8-3.5 mmol/l) and an extremely low apolipoprotein B level of 0.16 g/l (normal 0.6-1.2 g/l). APOB gene sequencing revealed him to be a compound heterozygote with two mutations (R463W and V703I). APOB R463W has previously been reported to cause FHBL. Genetic sequencing of his first-degree relatives identified the APOB V703I mutation in his normolipidemic brother and father and the APOB R463W mutation in his mother and sister, both of whom have very low LDL cholesterol levels. These results suggest that the APOB V703I mutation alone does not cause the FHBL phenotype. However, it is possible that it has a contributory role to a more aggressive phenotype in the presence of APOB R463W.
Also flagged:gene expressiongastric cancergene expressionstumorreverse transcriptasecell adhesion
Journal Article2012-05-01✓ 1 SnippetLi ML, Li SG, Wu WG, Rao LH, Zhang L, Ding QC, Yang JH, Wu XS, Lu JH, Chen L, Dong P, Gu J, Zhang WJ, Liu YB.
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Abstract)
…of ATP4A, CLDN10,OLFM4, SAA1 and PROK2…
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<h4>Objective</h4>To explore the different gene expressions of normal versus tumor tissues of gastric cancer at molecular levels.<h4>Methods</h4>Gene chip technology was used to determine the differentially expressed genes between gastric cancer (n = 12) and normal tissues (n = 12) from December 2009 to June 2010 of Xinhua Hospital of Shanghai Jiaotong University School of Medicine. And reverse transcriptase (RT)-PCR was performed to validate the results of gene chip analysis.<h4>Results</h4>Sixty-nine up-regulated genes and 80 down-regulated genes were identified by significance analysis of microarrays (SAM). And these genes were correlated with cell adhesion, angiogenesis, cell proliferation and apoptosis, et al. They were also closely correlated with the signaling pathways of Wnt (1/151, 0.66%) and vascular endothelial growth factor (VEGF) (2/76, 2.63%). The differential expressions of ATP4A, CLDN10, OLFM4, SAA1 and PROK2 were confirmed by RT-PCR (0.94 ± 0.19 vs 4.33 ± 0.39, 1.00 ± 0.14 vs 3.04 ± 0.26, 5.37 ± 0.30 vs 1.02 ± 0.14, 4.37 ± 0.30 vs 0.95 ± 0.29, 2.62 ± 0.54 vs 1.35 ± 0.35, all P < 0.05).<h4>Conclusion</h4>The classifier genes identified in this study may be closely correlated with the carcinogenesis of gastric cancer.
Brain serotonin (5-HT) system has been implicated in pathophysiology of anxiety, depression, drug addiction, and schizophrenia. 5-HT2A receptor is involved in the mechanisms of stress-induced psychopathology and impulsive behavior. Here, we investigated the role of 5-HT2A receptor in the autoregulation of the brain 5-HT system. The chronic treatment with agonist of 5-HT2A receptor DOI (1.0 mg/kg, i.p./14 days) produced considerable decrease of 5-HT2A receptor-mediated "head-twitches" in AKR/J mice indicating desensitization of 5-HT2A receptors. Chronic DOI treatment failed to alter 5-HT2A receptor gene expression in the midbrain, hippocampus and frontal cortex. At the same time, the increase in the expression of the gene encoding key enzyme of 5-HT synthesis, tryptophan hydroxylase 2 (TPH2), the increase in TPH2 activity and 5-HT levels and decreased expression of serotonin transporter (5-HTT) gene was found in the midbrain of DOI-treated mice. The results provide new evidence of receptor-gene cross-talk in the brain 5-HT system and the implication of 5-HT2A receptor in the autoregulation of the brain 5-HT system.
Also flagged:Dipeptidyl Peptidase IVInsulin ResistanceSteatosisNonalcoholic Fatty Liver DiseaseNAFLDmetformin
Journal Article2012-05-01✓ 1 SnippetItou M, Kawaguchi T, Taniguchi E, Oriishi T, Sata M.
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I A O 0000613)
…Wilson disease orhemochromatosis(table 1 ).…
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A 67-year-old Asian woman was referred to Kurume University Hospital due to abnormal liver function tests. She was diagnosed with nonalcoholic fatty liver disease (NAFLD). NAFLD was treated by diet therapy with medication of metformin and pioglitazone; however, NAFLD did not improve. Subsequently, the patient was administered sitagliptin. Although her energy intake and physical activity did not change, her hemoglobin A1c level was decreased from 7.8 to 6.4% 3 months after treatment. Moreover, her serum insulin level and homeostasis model assessment-insulin resistance value were also improved, as was the severity of hepatic steatosis. These findings indicate that sitagliptin may improve insulin resistance and steatosis in patients with refractory NAFLD.
Vascular calcification is an independent risk factor for cardiovascular disease. Arterial calcification of the aorta and coronary, carotid, and peripheral arteries becomes more prevalent with age. Genome-wide association studies have identified regions of the genome linked to vascular calcification, and these same regions are linked to myocardial infarction risk. The 9p21 region linked to vascular disease and inflammation also associates with vascular calcification. In addition to these common variants, rare genetic defects can serve as primary triggers of accelerated and premature calcification. Infancy-associated calcific disorders are caused by loss-of-function mutations in ENPP1, an enzyme that produces extracellular pyrophosphate. Adult-onset vascular calcification is linked to mutations in NTE5, another enzyme that regulates extracellular phosphate metabolism. Common conditions that secondarily enhance vascular calcification include atherosclerosis, metabolic dysfunction, diabetes, and impaired renal clearance. Oxidative stress and vascular inflammation, along with biophysical properties, converge with these predisposing factors to promote soft tissue mineralization. Vascular calcification is accompanied by an osteogenic profile, and this osteogenic conversion is seen within the vascular smooth muscle as well as the matrix. Here, we review the genetic causes of medial calcification in the smooth muscle layer, focusing on recent discoveries of gene mutations that regulate extracellular matrix phosphate production and the role of S100 proteins as promoters of vascular calcification.
Also flagged:depressionschizophrenianeuropsychiatricADdopamineglutamate
Journal Article2012-05-01✓ 1 SnippetRodrigues R, Smith MA, Wang X, Perry G, Lee HG, Zhu X, Petersen RB.
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Alzheimer's disease (AD) exhibits a complex etiology that simultaneously manifests as a complex cellular, neurobiological, molecular, anatomic-physiological and clinical entity. Other significant psychiatric conditions, such as depression and schizophrenia, may also present with complex and concurrent clinical and/or molecular phenotypes. These neuropsychiatric pathologies also originate from both environmental and genetic factors. We analyzed the molecular phenotypes of AD and discuss them with respect to the classical theories, which we integrated into mechanisms that share molecular and/or anatomical connections. Based on these mechanisms, we propose an interaction model and discuss the model in light of studies that refute or support it. Given the spectrum of AD phenotypes, we limit the scope of our discussion to a few, which facilitates concrete analysis. In addition, the study of specific, individual pathogenic phenotypes may be critical to defining the complex mechanisms leading to AD, thereby improving strategies for developing novel therapies.
…ncy, myelodysplastic syndrome,hemochromatosis, or blood loss…
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Resistance to recombinant erythropoietin (rEPO) in hemodialysis patients may be due to inadequate iron recruitment and defect in iron use. In this cross over randomized clinical trial, 30 hemodialysis patients with serum ferritin levels of ≥500 ng/ml, hemoglobin ≤11.0 g/dl, and transferrin saturation (TSAT) of 20% or less were administrated intravenous iron (50-100 mg/wk) and rEPO (120-360 U/kg/wk) for 6 months. Patients were excluded if there was a clear explanation for rEPO hyporesponsiveness. Patients were divided into two groups. Group1 received standard care and 500 mg of intravenous ascorbic acid (IVAA) with each dialysis session in the first week of each month for a total of 3 months. Group 2 received standard care only. After 2 month washout period, groups were crossed over. Each month hemoglobin (Hb) was assessed. Iron, TIBC (transferrin iron binding capacity), TSAT, iPTH (intact parathyroid hormone), liver enzymes, albumin and cholesterol levels were measured every 3 months. After 3 months of intervention, Hb significantly increased from 10.11 to 12.19 g/dl (P <0 0.001; 95% confidence interval [CI] 2.7-1.4) and TSAT increased from 18.9 to 28.1% (P = 0.008; 95% CI 0.09-3), while ferritin and serum iron declined significantly from 1391 to 938 ng/ml (P = 0.001; 95% CI 216-689), 97.2 to 64.6 (P = 0.001; 95% CI 14.8-50.4) in the study group. Change of Hb over time in IVAA group was significant (P < 0.0005). There were significant differences between two groups in change of Hb level over time (P < 0.0005) and treatment effect (P = 0.002). Baseline laboratory tests were similar in the two groups and there was no carry over effect at phase 2. We showed that low amount of IVAA could reduce ferritin level and enhance Hb and TSAT, suggesting improved iron utilization.
Also flagged:nucleusDisc degenerative diseaseDDdegenerative lumbar scoliosisdisc herniationDisc degeneration
Journal Article2012-05-01✓ 1 SnippetSivakamasundari V, Lufkin T.
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The intervertebral disc (IVD) is a multi-component structure consisting of a heterogeneous population of cells that form the central nucleus pulposus, encased by the fibrous annulus fibrosus and the cartilage end-plate. The essential function of the IVD is to withstand biomechanical forces, confer tensile strength and flexibility in motion to the spine. Disc degenerative disease (DD) is a prevalent ailment that affects the general population, often manifesting either in the form of lower back pain or as deformities of the spine such as degenerative lumbar scoliosis or in severe cases as disc herniation. With the aid of mutant mouse models generated through traditional knock-out strategies and spontaneous mutants, scientists have been able to elucidate some of the fundamental mechanisms of embryonic IVD development. Mutual interaction between the notochord and vertebral bodies are instrumental in the proper formation of the IVD. In this review, the known and proposed molecular mechanisms underlying these processes and the areas that require further investigation are discussed. Sufficient knowledge on the molecular mechanisms of IVD formation and the etiology of IVD degeneration is currently lacking and this has greatly hampered efforts to design appropriate and effective therapies for DD. With the dawn of the next-generation sequencing and better tools to engineer the genome, elucidation of the mechanism of IVD formation and the molecular basis of the pathology of DD ought to be an appealing avenue for researchers to pursue.
Also flagged:Abl kinasescytoplasmic tyrosine kinasescancersAblBcrcancer
Journal Article2012-05-01No SnippetsHantschel O.
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Abl kinases are prototypic cytoplasmic tyrosine kinases and are involved in a variety of chromosomal aberrations in different cancers. This causes the expression of Abl fusion proteins, such as Bcr-Abl, that are constitutively activated and drivers of tumorigenesis. Over the past decades, biochemical and functional studies on the molecular mechanisms of Abl regulation have gone hand in hand with progression of our structural understanding of autoinhibited and active Abl conformations. In parallel, Abl oncoproteins have become prime molecular targets for cancer therapy, using adenosine triphosphate (ATP)-competitive kinase inhibitors, such as imatinib. Abl-targeting drugs serve as a paradigm for our understanding of kinase inhibitor action, specificity, and resistance development. In this review article, I will review the molecular mechanisms that are responsible for the regulation of Abl kinase activity and how oncogenic Abl fusions signal. Furthermore, past and ongoing efforts to target Abl oncoproteins using ATP-competitive and allosteric inhibitors, as well as future possibilities using combination therapy, will be discussed.
Also flagged:behavioraleating disordersalcoholismbehavioral disorderBrain-derived neurotrophic factorBDNF
Journal Article2012-05-01✓ 1 SnippetArcher T, Oscar-Berman M, Blum K, Gold M.
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Adverse, unfavourable life conditions, particularly during early life stages and infancy, can lead to epigenetic regulation of genes involved in stress-response, behavioral disinhibition, and cognitive-emotional systems. Over time, the ultimate final outcome can be expressed through behaviors bedeviled by problems with impulse control, such as eating disorders, alcoholism, and indiscriminate social behavior. While many reward gene polymorphisms are involved in impulsive behaviors, a polymorphism by itself may not translate to the development of a particular behavioral disorder unless it is impacted by epigenetic effects. Brain-derived neurotrophic factor (BDNF) affects the development and integrity of the noradrenergic, dopaminergic, serotonergic, glutamatergic, and cholinergic neurotransmitter systems, and plasma levels of the neurotrophin are associated with both cognitive and aggressive impulsiveness. Epigenetic mechanisms associated with a multitude of environmental factors, including premature birth, low birth weight, prenatal tobacco exposure, non-intact family, young maternal age at birth of the target child, paternal history of antisocial behavior, and maternal depression, alter the developmental trajectories for several neuropsychiatric disorders. These mechanisms affect brain development and integrity at several levels that determine structure and function in resolving the final behavioral expressions.
Most researchers believe that neurogenesis in mature mammals is restricted only to the subgranular zone of the dentate gyrus and the subventricular zone of the lateral ventricle in the central nervous system. In the peripheral nervous system, neurogenesis is thought to be active only during prenatal development, with the exception of the olfactory neuroepithelium. However, sensory ganglia in the adult peripheral nervous system have been reported to contain precursor cells that can proliferate in vitro and be induced to differentiate into neurons. The occurrence of insult-induced neurogenesis, which has been reported by several investigators in the brain, is limited to a few recent reports for the peripheral nervous system. These reports suggest that damage to the adult nervous system induces mechanisms similar to those that control the generation of new neurons during prenatal development. Understanding conditions under which neurogenesis can be induced in physiologically non-neurogenic regions in adults is one of the major challenges for developing therapeutic strategies to repair neurological damage. However, the induced neurogenesis in the peripheral nervous system is still largely unexplored. This review presents the history of research on adult neurogenesis in the peripheral nervous system, which dates back more than 100 years and reveals the evidence on the under estimated potential for generation of new neurons in the adult peripheral nervous system.