Also flagged:antithrombin deficiencytype I deficiencytype II deficiencyheparinbindingprotease
Journal Article2010-04-30✓ 4 SnippetsMartínez-Martínez I, Ordóñez A, Navarro-Fernández J, Pérez-Lara A, Gutiérrez-Gallego R, Giraldo R, Martínez C, Llop E, Vicente V, Corral J.
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Abstract)
…Identification of mutations in the SERPINC1 gene has revealed different mechanisms responsible for antithrombin deficiency.…
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…<h4>Background</h4>Identification of mutations in the SERPINC1 gene has revealed different mechanisms responsible for antithrombin deficiency.…
Abstract)
…mutations in theSERPINC1gene has revealed…
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<h4>Background</h4>Identification of mutations in the SERPINC1 gene has revealed different mechanisms responsible for antithrombin deficiency. Deletions and nonsense mutations associate with type I deficiency. Certain missense mutations cause type II deficiency by affecting the heparin binding site or the reactive center loop, while others result in type I deficiency by intracellular retention or RNA instability.<h4>Design and methods</h4>We studied the molecular, biochemical, proteomic and glycomic characterization of a new natural mutant (K241E) that may be classified as pleiotropic.<h4>Results</h4>The mutation caused a significant decrease in the anticoagulant activity mainly due to a reduced heparin affinity and a modification of the electrostatic potential that might explain the impaired ability of the mutant protein to form complexes with the target protease in the absence of heparin. Mass spectrometry and glycomic analyses confirmed an increased molecular weight of 800 Da in the mutant protein possibly due to core-fucosylation, provoking the loss of heparin affinity. Additionally, carriers of this mutation also have a minor mutant isoform that still followed normal glycosylation, retaining similar heparin affinity to wild-type alpha-antithrombin, and certain anticoagulant activity, which may explain the milder thrombotic risk of patients carrying this mutation. Similar results were observed using recombinant K241E antithrombin molecules.<h4>Conclusions</h4>Our data suggest a new mechanism involved in antithrombin type II deficiency by indirectly affecting the glycosylation of a natural variant. Additional studies are required to confirm this hypothesis.
Cleavage of viral DNA by the bacterial Type III Restriction-Modification enzymes requires the ATP-dependent long-range communication between a distant pair of DNA recognition sequences. The classical view is that Type III endonuclease activity is only activated by a pair of asymmetric sites in a specific head-to-head inverted repeat. Based on this assumption and due to the presence of helicase domains in Type III enzymes, various motor-driven DNA translocation models for communication have been suggested. Using both single-molecule and ensemble assays we demonstrate that Type III enzymes can also cleave DNA with sites in tail-to-tail repeat with high efficiency. The ability to distinguish both inverted repeat substrates from direct repeat substrates in a manner independent of DNA topology or accessory proteins can only be reconciled with an alternative sliding mode of communication.
Journal Article2010-04-30✓ 1 SnippetBüssing I, Yang JS, Lai EC, Grosshans H.
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…TheCSE1L/CAS orthologue, XPO-2, has…
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MicroRNA (miRNA) biogenesis proceeds from a primary transcript (pri-miRNA) through the pre-miRNA into the mature miRNA. Here, we identify a role of the Caenorhabditis elegans nuclear export receptor XPO-1 and the cap-binding proteins CBP-20/NCBP-2 and CBP-80/NCBP-1 in this process. The RNA-mediated interference of any of these genes causes retarded heterochronic phenotypes similar to those observed for animals with mutations in the let-7 miRNA or core miRNA machinery genes. Moreover, pre- and mature miRNAs become depleted, whereas primary miRNA transcripts accumulate. An involvement of XPO-1 in miRNA biogenesis is conserved in Drosophila, in which knockdown of Embargoed/XPO-1 or its chemical inhibition through leptomycin B causes pri-miRNA accumulation. Our findings demonstrate that XPO-1/Emb promotes the pri-miRNA-to-pre-miRNA processing and we propose that this function involves intranuclear transport and/or nuclear export of primary miRNAs.
<h4>Background</h4>Shigella flexneri inhibits apoptosis in infected epithelial cells. In order to understand the pro-survival effects induced by the bacteria, we utilized apoptosis-specific microarrays to analyze the changes in eukaryotic gene expression in both infected and uninfected cells in the presence and absence of staurosporine, a chemical inducer of the intrinsic pathway of apoptosis. The goal of this research was to identify host factors that contribute to apoptosis inhibition in infected cells.<h4>Results</h4>The microarray analysis revealed distinct expression profiles in uninfected and infected cells, and these changes were altered in the presence of staurosporine. These profiles allowed us to make comparisons between the treatment groups. Compared to uninfected cells, Shigella-infected epithelial cells, both in the presence and absence of staurosporine, showed significant induced expression of JUN, several members of the inhibitor of apoptosis gene family, nuclear factor kappaB and related genes, genes involving tumor protein 53 and the retinoblastoma protein, and surprisingly, genes important for the inhibition of the extrinsic pathway of apoptosis. We confirmed the microarray results for a selection of genes using in situ hybridization analysis.<h4>Conclusion</h4>Infection of epithelial cells with S. flexneri induces a pro-survival state in the cell that results in apoptosis inhibition in the presence and absence of staurosporine. The bacteria may target these host factors directly while some induced genes may represent downstream effects due to the presence of the bacteria. Our results indicate that the bacteria block apoptosis at multiple checkpoints along both pathways so that even if a cell fails to prevent apoptosis at an early step, Shigella will block apoptosis at the level of caspase-3. Apoptosis inhibition is most likely vital to the survival of the bacteria in vivo. Future characterization of these host factors is required to fully understand how S. flexneri inhibits apoptosis in epithelial cells.
Also flagged:infectioncancerteratocarcinomascancersviral infectionscell proliferation
Journal Article2010-04-29No SnippetsSell S.
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In each major theory of the origin of cancer-field theory, chemical carcinogenesis, infection, mutation, or epigenetic change-the tissue stem cell is involved in the generation of cancer. Although the cancer type is identified by the more highly differentiated cells in the cancer cell lineage or hierarchy (transit-amplifying cells), the property of malignancy and the molecular lesion of the cancer exist in the cancer stem cell. In the case of teratocarcinomas, normal germinal stem cells have the potential to become cancers if placed in an environment that allows expression of the cancer phenotype (field theory). In cancers due to chemically induced mutations, viral infections, somatic and inherited mutations, or epigenetic changes, the molecular lesion or infection usually first occurs in the tissue stem cells. Cancer stem cells then give rise to transit-amplifying cells and terminally differentiated cells, similar to what happens in normal tissue renewal. However, the major difference between cancer growth and normal tissue renewal is that whereas normal transit amplifying cells usually differentiate and die, at various levels of differentiation, the cancer transit-amplifying cells fail to differentiate normally and instead accumulate (ie, they undergo maturation arrest), resulting in cancer growth.
…ligand netrin promotedDCC-mediated translation and disa…
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Extracellular signals regulate protein translation in many cell functions. A key advantage of control at the translational level is the opportunity to regulate protein synthesis within specific cellular subregions. However, little is known about mechanisms that may link extracellular cues to translation with spatial precision. Here, we show that a transmembrane receptor, DCC, forms a binding complex containing multiple translation components, including eukaryotic initiation factors, ribosomal large and small subunits, and monosomes. In neuronal axons and dendrites DCC colocalizes in particles with translation machinery, and newly synthesized protein. The extracellular ligand netrin promoted DCC-mediated translation and disassociation of translation components. The functional and physical association of a cell surface receptor with the translation machinery leads to a generalizable model for localization and extracellular regulation of protein synthesis, based on a transmembrane translation regulation complex.
Also flagged:deathsynapseaxonendosomesneurotrophic factorsaxonal
Journal Article2010-04-29✓ 1 SnippetPerlson E, Maday S, Fu MM, Moughamian AJ, Holzbaur EL.
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Active transport along the axon is crucial to the neuron. Motor-driven transport supplies the distal synapse with newly synthesized proteins and lipids, and clears damaged or misfolded proteins. Microtubule motors also drive long-distance signaling along the axon via signaling endosomes. Although positive signaling initiated by neurotrophic factors has been well-studied, recent research has focused on stress-signaling along the axon. Here, the connections between axonal transport alterations and neurodegeneration are discussed, including evidence for defective transport of vesicles, mitochondria, degradative organelles, and signaling endosomes in models of amyotrophic lateral sclerosis, Huntington's, Parkinson's and Alzheimer's disease. Defects in transport are sufficient to induce neurodegeneration, but recent progress suggests that changes in retrograde signaling pathways correlate with rapidly progressive neuronal cell death.
Also flagged:histone chaperoneLinker histone H1chromatinhistonechaperonesdegradation
Journal Article2010-04-29✓ 1 SnippetGeorge EM, Brown DT.
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Linker histone H1 binds with high affinity to naked and nucleosomal DNA in vitro but is rapidly exchanged between chromatin sites in vivo suggesting the involvement of one or more linker histone chaperones. Using permeabilized cells, we demonstrate that the small acidic protein prothymosin alpha (ProTalpha) can facilitate H1 displacement from and deposition onto the native chromatin template. Depletion of ProTalpha levels in vivo by siRNA-mediated mRNA degradation resulted in a decreased rate of exchange of linker histones as assayed by photobleaching techniques. These results indicate that ProTalpha is a component of a linker histone chaperone.
Schistosoma blood flukes, which infect over 200 million people globally, co-opt CD4+ T cell-dependent mechanisms to facilitate parasite development and egg excretion. The latter requires Th2 responses, while the mechanism underpinning the former has remained obscure. Using mice that are either defective in T cell receptor (TCR) signaling or that lack TCRs that can respond to schistosomes, we show that naïve CD4+ T cells facilitate schistosome development in the absence of T cell receptor signaling. Concurrently, the presence of naïve CD4+ T cells correlates with both steady-state changes in the expression of genes that are critical for the development of monocytes and macrophages and with significant changes in the composition of peripheral mononuclear phagocyte populations. Finally, we show that direct stimulation of the mononuclear phagocyte system restores blood fluke development in the absence of CD4+ T cells. Thus we conclude that schistosomes co-opt innate immune signals to facilitate their development and that the role of CD4+ T cells in this process may be limited to the provision of non-cognate help for mononuclear phagocyte function. Our findings have significance for understanding interactions between schistosomiasis and other co-infections, such as bacterial infections and human immunodeficiency virus infection, which potently stimulate innate responses or interfere with T cell help, respectively. An understanding of immunological factors that either promote or inhibit schistosome development may be valuable in guiding the development of efficacious new therapies and vaccines for schistosomiasis.
Polyglutamine (polyQ) expansion in exon1 (XN1) of the huntingtin protein is linked to Huntington's disease. When the number of glutamines exceeds a threshold of approximately 36-40 repeats, XN1 can readily form amyloid aggregates similar to those associated with disease. Many experiments suggest that misfolding of monomeric XN1 plays an important role in the length-dependent aggregation. Elucidating the misfolding of a XN1 monomer can help determine the molecular mechanism of XN1 aggregation and potentially help develop strategies to inhibit XN1 aggregation. The flanking sequences surrounding the polyQ region can play a critical role in determining the structural rearrangement and aggregation mechanism of XN1. Few experiments have studied XN1 in its entirety, with all flanking regions. To obtain structural insights into the misfolding of XN1 toward amyloid aggregation, we perform molecular dynamics simulations on monomeric XN1 with full flanking regions, a variant missing the polyproline regions, which are hypothesized to prevent aggregation, and an isolated polyQ peptide (Q(n)). For each of these three constructs, we study glutamine repeat lengths of 23, 36, 40 and 47. We find that polyQ peptides have a positive correlation between their probability to form a beta-rich misfolded state and their expansion length. We also find that the flanking regions of XN1 affect its probability to form a beta-rich state compared to the isolated polyQ. Particularly, the polyproline regions form polyproline type II helices and decrease the probability of the polyQ region to form a beta-rich state. Additionally, by lengthening polyQ, the first N-terminal 17 residues are more likely to adopt a beta-sheet conformation rather than an alpha-helix conformation. Therefore, our molecular dynamics study provides a structural insight of XN1 misfolding and elucidates the possible role of the flanking sequences in XN1 aggregation.
Also flagged:HOXB13DNMT3BtumorhypermethylationDNA methyltransferasesDNA methyltransferase
Journal Article2010-04-29✓ 5 SnippetsGhoshal K, Motiwala T, Claus R, Yan P, Kutay H, Datta J, Majumder S, Bai S, Majumder A, Huang T, Plass C, Jacob ST.
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…COBRA showed that the CGIs encompassing the promoter and/or coding region of DCC, TBX5, TBX18, SLIT1 were methylated in primary colorectal tumors but not in matching normal colon tissues whereas G…
Abstract)
…COBRA showed that the CGIs encompassing the promoter and/or coding region of DCC, TBX5, TBX18, SLIT1 were methylated in primary colorectal tumors but not in matching normal colon tissues whereas GNA11 was methylated in both.…
Results)
…TBX18, DCC and CAVEOLIN 1 were re-expressed in RKO cells treated with 1 and 2.5 μM decitabine as early as 24 hr and their expression persisted up to 72 hr (Figure 2B).…
Discussion)
…The targets identified include not only well known tumor suppressors such as P16/INK4A, DCC, CAVEOLIN1, PGRMC1 but also novel genes like TBX18, TBX5, SLIT1, DGKI.…
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…Further, analysis of a subset of these genes (DCC, TBX18, TBX5, SLIT1) in primary colon cancer revealed tumor-specific methylation.…
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<h4>Background</h4>A hallmark of cancer cells is hypermethylation of CpG islands (CGIs), which probably arises from upregulation of one or more DNA methyltransferases. The purpose of this study was to identify the targets of DNMT3B, an essential DNA methyltransferase in mammals, in colon cancer.<h4>Methodology/principal findings</h4>Chromatin immunoprecipitation with DNMT3B specific antibody followed by CGI microarray identified genes with or without CGIs, repeat elements and genomic contigs in RKO cells. ChIP-Chop analysis showed that the majority of the target genes including P16, DCC, DISC1, SLIT1, CAVEOLIN1, GNA11, TBX5, TBX18, HOXB13 and some histone variants, that harbor CGI in their promoters, were methylated in multiple colon cancer cell lines but not in normal colon epithelial cells. Further, these genes were reactivated in RKO cells after treatment with 5-aza-2'-deoxycytidine, a DNA hypomethylating agent. COBRA showed that the CGIs encompassing the promoter and/or coding region of DCC, TBX5, TBX18, SLIT1 were methylated in primary colorectal tumors but not in matching normal colon tissues whereas GNA11 was methylated in both. MassARRAY analysis demonstrated that the CGI located approximately 4.5 kb upstream of HOXB13 +1 site was tumor-specifically hypermethylated in primary colorectal cancers and cancer cell lines. HOXB13 upstream CGI was partially hypomethylated in DNMT1(-/-) HCT cells but was almost methylation free in cells lacking both DNMT1 and DNMT3B. Analysis of tumor suppressor properties of two aberrantly methylated transcription factors, HOXB13 and TBX18, revealed that both inhibited growth and clonogenic survival of colon cancer cells in vitro, but only HOXB13 abolished tumor growth in nude mice.<h4>Conclusions/significance</h4>This is the first report that identifies several important tumor suppressors and transcription factors as direct DNMT3B targets in colon cancer and as potential biomarkers for this cancer. Further, this study shows that methylation at an upstream CGI of HOXB13 is unique to colon cancer.
Cigarette smoking is the main preventable cause of death in developed countries, and the development of more effective treatments is necessary. Cumulating evidence suggests that cognitive enhancement may contribute to the addictive actions of nicotine. Several studies have demonstrated that nicotine enhances cognitive performance in both smokers and non-smokers. Genetic studies support the role of both dopamine (DA) and nicotinic acetylcholine receptors (nAChRs) associated with nicotine-induced cognitive enhancement. Based on knockout mice studies, beta2 nAChRs are thought to be essential in mediating the cognitive effects of nicotine. alpha7nAChRs are associated with attentional and sensory filtering response, especially in schizophrenic individuals. Genetic variation in D2 type DA receptors and the catechol-O-methyltransferase enzyme appears to moderate cognitive deficits induced by smoking abstinence. Serotonin transporter (5-HTT) gene variation also moderates nicotine-induced improvement in spatial working memory. Less is known about the contribution of genetic variation in DA transporter and D4 type DA receptor genetic variation on the cognitive effects of nicotine. Future research will provide a clearer understanding of the mechanism underlying the cognitive-enhancing actions of nicotine.
The sigma-1 receptor is a unique non-opioid, non-PCP binding site that has been implicated in many different pathophysiological conditions including psychosis, drug addiction, retinal degeneration and cancer. Based on the structure of fenpropimorph, a high affinity (K(i)=0.005 nM)(1) sigma-1 receptor ligand and strong inhibitor of the yeast sterol isomerase (ERG2), we previously deduced a basic sigma-1 receptor pharmacophore or chemical backbone composed of a phenyl ring attached to a di-substituted nitrogen atom via an alkyl chain.(2) Here, we report the design and synthesis of various N,N-dialkyl or N-alkyl-N-aralkyl derivatives based on this pharmacophore as well as their binding affinities to the sigma-1 receptor. We introduce three high affinity sigma-1 receptor compounds, N,N-dibutyl-3-(4-fluorophenyl)propylamine (9), N,N-dibutyl-3-(4-nitrophenyl)propylamine (3), and N-propyl-N'-4-aminophenylethyl-3-(4-nitrophenyl)propylamine (20) with K(i) values of 17.7 nM, 0.36 nM, and 6 nM, respectively. In addition to sigma receptor affinity, we show through cytotoxicity assays that growth inhibition of various tumor cell lines occurs with our high affinity N,N-dialkyl or N-alkyl-N-aralkyl derivatives.
Also flagged:gene expressioncell divisionsmethylationbreast cancerhistonehypomethylation
Journal Article2010-04-29No SnippetsJovanovic J, Rønneberg JA, Tost J, Kristensen V.
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Epigenetic changes can be defined as stable molecular alterations of a cellular phenotype such as the gene expression profile of a cell that are heritable during somatic cell divisions (and sometimes germ line transmissions) but do not involve changes of the DNA sequence itself. Epigenetic phenomena are mediated by several molecular mechanisms comprising histone modifications, polycomb/trithorax protein complexes, small non-coding or antisense RNAs and DNA methylation. These different modifications are closely interconnected. Epigenetic regulation is critical in normal growth and development and closely conditions the transcriptional potential of genes. Epigenetic mechanisms convey genomic adaption to an environment thereby ultimately contributing towards given phenotype. In this review we will describe the various aspects of epigenetics and in particular DNA methylation in breast carcinogenesis and their potential application for diagnosis, prognosis and treatment decision.
…Proteomics analyses showed that peroxiredoxin (PRDX6) and prohibin (PHB) are key targets of luteolin.…
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Artemisia annua is currently the only commercial source of the sesquiterpene lactone artemisinin.Since artemisinin was discovered as the active component of A. annua in early 1970s, hundreds of papers have focused on the anti-parasitic effects of artemisinin and its semi-synthetic analogs dihydroartemisinin, artemether, arteether, and artesunate. Artemisinin per se has not been used in mainstream clinical practice due to its poor bioavailability when compared to its analogs. In the past decade, the work with artemisinin-based compounds has expanded to their anti-cancer properties. Although artemisinin is a major bioactive component present in the traditional Chinese herbal preparations (tea), leaf flavonoids, also present in the tea, have shown a variety of biological activities and may synergize the effects of artemisinin against malaria and cancer. However, only a few studies have focused on the potential synergistic effects between flavonoids and artemisinin. The resurgent idea that multi-component drug therapy might be better than monotherapy is illustrated by the recent resolution of the World Health Organization to support artemisinin-based combination therapies (ACT), instead of the previously used monotherapy with artemisinins. In this critical review we will discuss the possibility that artemisinin and its semi-synthetic analogs might become more effective to treat parasitic diseases (such as malaria) and cancer if simultaneously delivered with flavonoids. The flavonoids present in A. annua leaves have been linked to suppression of CYP450 enzymes responsible for altering the absorption and metabolism of artemisinin in the body, but also have been linked to a beneficial immunomodulatory activity in subjects afflicted with parasitic and chronic diseases.
<h4>Background</h4>The prostate gland represents a multifaceted system in which prostate epithelia and stroma have distinct physiological roles. To understand the interaction between stroma and glandular epithelia, it is essential to delineate the gene expression profiles of these two tissue types in prostate cancer. Most studies have compared tumor and normal samples by performing global expression analysis using a mixture of cell populations. This report presents the first study of prostate tumor tissue that examines patterns of differential expression between specific cell types using laser capture microdissection (LCM).<h4>Methods</h4>LCM was used to isolate distinct cell-type populations and identify their gene expression differences using oligonucleotide microarrays. Ten differentially expressed genes were then analyzed in paired tumor and non-neoplastic prostate tissues by quantitative real-time PCR. Expression patterns of the transcription factors, WT1 and EGR1, were further compared in established prostate cell lines. WT1 protein expression was also examined in prostate tissue microarrays using immunohistochemistry.<h4>Results</h4>The two-step method of laser capture and microarray analysis identified nearly 500 genes whose expression levels were significantly different in prostate epithelial versus stromal tissues. Several genes expressed in epithelial cells (WT1, GATA2, and FGFR-3) were more highly expressed in neoplastic than in non-neoplastic tissues; conversely several genes expressed in stromal cells (CCL5, CXCL13, IGF-1, FGF-2, and IGFBP3) were more highly expressed in non-neoplastic than in neoplastic tissues. Notably, EGR1 was also differentially expressed between epithelial and stromal tissues. Expression of WT1 and EGR1 in cell lines was consistent with these patterns of differential expression. Importantly, WT1 protein expression was demonstrated in tumor tissues and was absent in normal and benign tissues.<h4>Conclusions</h4>The prostate represents a complex mix of cell types and there is a need to analyze distinct cell populations to better understand their potential interactions. In the present study, LCM and microarray analysis were used to identify novel gene expression patterns in prostate cell populations, including identification of WT1 expression in epithelial cells. The relevance of WT1 expression in prostate cancer was confirmed by analysis of tumor tissue and cell lines, suggesting a potential role for WT1 in prostate tumorigenesis.
<h4>Background</h4>We obtained a series of pituitary adenoma proteomic expression data, including protein-mapping data (111 proteins), comparative proteomic data (56 differentially expressed proteins), and nitroproteomic data (17 nitroproteins). There is a pressing need to clarify the significant signaling pathway networks that derive from those proteins in order to clarify and to better understand the molecular basis of pituitary adenoma pathogenesis and to discover biomarkers. Here, we describe the significant signaling pathway networks that were mined from human pituitary adenoma proteomic data with the Ingenuity pathway analysis system.<h4>Methods</h4>The Ingenuity pathway analysis system was used to analyze signal pathway networks and canonical pathways from protein-mapping data, comparative proteomic data, adenoma nitroproteomic data, and control nitroproteomic data. A Fisher's exact test was used to test the statistical significance with a significance level of 0.05. Statistical significant results were rationalized within the pituitary adenoma biological system with literature-based bioinformatics analyses.<h4>Results</h4>For the protein-mapping data, the top pathway networks were related to cancer, cell death, and lipid metabolism; the top canonical toxicity pathways included acute-phase response, oxidative-stress response, oxidative stress, and cell-cycle G2/M transition regulation. For the comparative proteomic data, top pathway networks were related to cancer, endocrine system development and function, and lipid metabolism; the top canonical toxicity pathways included mitochondrial dysfunction, oxidative phosphorylation, oxidative-stress response, and ERK/MAPK signaling. The nitroproteomic data from a pituitary adenoma were related to cancer, cell death, lipid metabolism, and reproductive system disease, and the top canonical toxicity pathways mainly related to p38 MAPK signaling and cell-cycle G2/M transition regulation. Nitroproteins from a pituitary control related to gene expression and cellular development, and no canonical toxicity pathways were identified.<h4>Conclusions</h4>This pathway network analysis demonstrated that mitochondrial dysfunction, oxidative stress, cell-cycle dysregulation, and the MAPK-signaling abnormality are significantly associated with a pituitary adenoma. These pathway-network data provide new insights into the molecular mechanisms of human pituitary adenoma pathogenesis, and new clues for an in-depth investigation of pituitary adenoma and biomarker discovery.
Journal Article2010-04-28✓ 2 SnippetsEberle I, Pless B, Braun M, Dingermann T, Marschalek R.
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…1 of theSLC2A14gene ( 9…
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…coding for theSLC2A14gene.…
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Transcripts of NANOG and OCT4 have been recently identified in human t(4;11) leukemia and in a model system expressing both t(4;11) fusion proteins. Moreover, downstream target genes of NANOG/OCT4/SOX2 were shown to be transcriptionally activated. However, the NANOG1 gene belongs to a gene family, including a gene tandem duplication (named NANOG2 or NANOGP1) and several pseudogenes (NANOGP2-P11). Thus, it was unclear which of the NANOG family members were transcribed in t(4;11) leukemia cells. 5'-RACE experiments revealed novel 5'-exons of NANOG1 and NANOG2, which could give rise to the expression of two different NANOG1 and three different NANOG2 protein variants. Moreover, a novel PCR-based method was established that allows distinguishing between transcripts deriving from NANOG1, NANOG2 and all other NANOG pseudogenes (P2-P11). By applying this method, we were able to demonstrate that human hematopoietic stem cells and different leukemic cells transcribe NANOG2. Furthermore, we functionally tested NANOG1 and NANOG2 protein variants by recombinant expression in 293 cells. These studies revealed that NANOG1 and NANOG2 protein variants are functionally equivalent and activate a regulatory circuit that activates specific stem cell genes. Therefore, we pose the hypothesis that the transcriptional activation of NANOG2 represents a 'gain-of-stem cell function' in acute leukemia.
Also flagged:Ribosome-binding proteinsBiogenesismitochondrialsynthesismembrane-ribosomes
Journal Article2010-04-28✓ 1 SnippetBauerschmitt H, Mick DU, Deckers M, Vollmer C, Funes S, Kehrein K, Ott M, Rehling P, Herrmann JM.
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…the presence ofMrpl39in the eluate,…
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Biogenesis of respiratory chain complexes depends on the expression of mitochondrial-encoded subunits. Their synthesis occurs on membrane-associated ribosomes and is probably coupled to their membrane insertion. Defects in expression of mitochondrial translation products are among the major causes of mitochondrial disorders. Mdm38 is related to Letm1, a protein affected in Wolf-Hirschhorn syndrome patients. Like Mba1 and Oxa1, Mdm38 is an inner membrane protein that interacts with ribosomes and is involved in respiratory chain biogenesis. We find that simultaneous loss of Mba1 and Mdm38 causes severe synthetic defects in the biogenesis of cytochrome reductase and cytochrome oxidase. These defects are not due to a compromised membrane binding of ribosomes but the consequence of a mis-regulation in the synthesis of Cox1 and cytochrome b. Cox1 expression is restored by replacing Cox1-specific regulatory regions in the mRNA. We conclude, that Mdm38 and Mba1 exhibit overlapping regulatory functions in translation of selected mitochondrial mRNAs.
Also flagged:p53tumorstranscription factorRNAP IIhistone modifying enzymeschromatin remodeling factors
Journal Article2010-04-28No SnippetsBeckerman R, Prives C.
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Inactivation of p53 is critical for the formation of most tumors. Illumination of the key function(s) of p53 protein in protecting cells from becoming cancerous is therefore a worthy goal. Arguably p53's most important function is to act as a transcription factor that directly regulates perhaps several hundred of the cell's RNA polymerase II (RNAP II)-transcribed genes, and indirectly regulates thousands of others. Indeed p53 is the most well studied mammalian transcription factor. The p53 tetramer binds to its response element where it can recruit diverse transcriptional coregulators such as histone modifying enzymes, chromatin remodeling factors, subunits of the mediator complex, and components of general transcription machinery and preinitiation complex (PIC) to modulate RNAPII activity at target loci (Laptenko and Prives 2006). The p53 transcriptional program is regulated in a stimulus-specific fashion (Murray-Zmijewski et al. 2008; Vousden and Prives 2009), whereby distinct subsets of p53 target genes are induced in response to different p53-activating agents, likely allowing cells to tailor their response to different types of stress. How p53 is able to discriminate between these different loci is the subject of intense research. Here, we describe key aspects of the fundamentals of p53-mediated transcriptional regulation and target gene promoter selectivity.
The plasma profile of subjects with nonalcoholic fatty liver disease (NAFLD), steatosis, and steatohepatitis (NASH) was examined using an untargeted global metabolomic analysis to identify specific disease-related patterns and to identify potential noninvasive biomarkers. Plasma samples were obtained after an overnight fast from histologically confirmed nondiabetic subjects with hepatic steatosis (n = 11) or NASH (n = 24) and were compared with healthy, age- and sex-matched controls (n = 25). Subjects with NAFLD were obese, were insulin resistant, and had higher plasma concentrations of homocysteine and total cysteine and lower plasma concentrations of total glutathione. Metabolomic analysis showed markedly higher levels of glycocholate, taurocholate, and glycochenodeoxycholate in subjects with NAFLD. Plasma concentrations of long-chain fatty acids were lower and concentrations of free carnitine, butyrylcarnitine, and methylbutyrylcarnitine were higher in NASH. Several glutamyl dipeptides were higher whereas cysteine-glutathione levels were lower in NASH and steatosis. Other changes included higher branched-chain amino acids, phosphocholine, carbohydrates (glucose, mannose), lactate, pyruvate, and several unknown metabolites. Random forest analysis and recursive partitioning of the metabolomic data could separate healthy subjects from NAFLD with an error rate of approximately 8% and separate NASH from healthy controls with an error rate of 4%. Hepatic steatosis and steatohepatitis could not be separated using the metabolomic profile. Plasma metabolomic analysis revealed marked changes in bile salts and in biochemicals related to glutathione in subjects with NAFLD. Statistical analysis identified a panel of biomarkers that could effectively separate healthy controls from NAFLD and healthy controls from NASH. These biomarkers can potentially be used to follow response to therapeutic interventions.
Also flagged:tumortumorsTGFβcell motilitybreast cancercancer
Journal Article2010-04-27No SnippetsGiampieri S, Pinner S, Sahai E.
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Transforming growth factor beta (TGFbeta) has seemingly contradictory roles in tumor progression: it can promote metastatic invasion but also act as a tumor suppressor. Recently, two studies have used intravital imaging to unravel the role of TGFbeta at different stages of the metastatic process. TGFbeta promotes single cell motility, which enables invasion into blood vessels. However the activation of TGFbeta signaling is a transient event and is not maintained at distant sites. The downregulation of TGFbeta signaling at secondary sites then permits growth of secondary tumors. In the absence of TGFbeta, cells are restricted to collective movement and lymphatic spread. Here, we discuss these findings and their potential implications.
Also flagged:G-protein RhesSUMO-E3 ligasesumoylationsmall ubiquitin-like modifierE1Ubc9
Journal Article2010-04-27✓ 1 SnippetSubramaniam S, Mealer RG, Sixt KM, Barrow RK, Usiello A, Snyder SH.
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We recently reported that the small G-protein Rhes has the properties of a SUMO-E3 ligase and mediates mutant huntingtin (mHtt) cytotoxicity. We now demonstrate that Rhes is a physiologic regulator of sumoylation, which is markedly reduced in the corpus striatum of Rhes-deleted mice. Sumoylation involves activation and transfer of small ubiquitin-like modifier (SUMO) from the thioester of E1 to the thioester of Ubc9 (E2) and final transfer to lysines on target proteins, which is enhanced by E3s. We show that E1 transfers SUMO from its thioester directly to lysine residues on Ubc9, forming isopeptide linkages. Conversely, sumoylation on E1 requires transfer of SUMO from the thioester of Ubc9. Thus, the process regarded as "autosumoylation" reflects intermolecular transfer between E1 and Ubc9, which we designate "cross-sumoylation." Rhes binds directly to both E1 and Ubc9, enhancing cross-sumoylation as well as thioester transfer from E1 to Ubc9.
Also flagged:irritable bowel syndromeIBSGIconstipationcorticotrophin releasing hormonesmotility disorder
Journal Article2010-04-27No SnippetsLee OY.
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Altered motility remains one of the important pathophysiologic factors in patients with irritable bowel syndrome (IBS) who commonly complain of abdominal pain and stool changes such as diarrhea and constipation. The prevalence of IBS has increased among Asian populations these days. Gastrointestinal (GI) physiology may vary between Asian and Western populations because of differences in diets, socio-cultural backgrounds, and genetic factors. The characteristics and differences of GI dysmotility in Asian IBS patients were reviewed. MEDLINE search work was performed including following terms, 'IBS,' 'motility,' 'transit time,' 'esophageal motility,' 'gastric motility,' 'small intestinal motility,' 'colonic motility,' 'anorectal function,' and 'gallbladder motility' and over 100 articles were categorized under 'esophagus,' 'stomach,' 'small intestine,' 'colon,' 'anorectum,' 'gallbladder,' 'transit,' 'motor pattern,' and 'effect of stressors.' Delayed gastric emptying, slow tansit in constipation predominant IBS patients, rapid transit in diarrhea predominant IBS patients, accelerated motility responses to various stressors such as meals, mental stress, or corticotrophin releasing hormones, and altered rectal compliance and altered rectal accomodation were reported in many Asian studies regarding IBS. Many conflicting results were found among these studies and there are still controversies to conclude these as unique features of Asian IBS patients. Multinational and multicenter studies are needed to be performed vigorously in order to elaborate characteristics as well as differences of altered motililty in Asian patients with IBS.
Also flagged:Alcohol use disordersalcohol dependencyAlcoholic liver diseaseethanolinflammatory responseliver steatosis
Journal Article2010-04-27No SnippetsMiranda-Mendez A, Lugo-Baruqui A, Armendariz-Borunda J.
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Alcohol use disorders and alcohol dependency affect millions of individuals worldwide. The impact of these facts lies in the elevated social and economic costs. Alcoholic liver disease is caused by acute and chronic exposure to ethanol which promotes oxidative stress and inflammatory response. Chronic consumption of ethanol implies liver steatosis, which is the first morphological change in the liver, followed by liver fibrosis and cirrhosis. This review comprises a broad approach of alcohol use disorders, and a more specific assessment of the pathophysiologic molecular basis, and genetics, as well as clinical presentation and current modalities of treatment for alcoholic liver disease.
Also flagged:styrylquinolineAIDSintegraseRaltegravirreverse transcriptaseprotease
Journal Article2010-04-27No SnippetsMouscadet JF, Desmaële D.
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In spite of significant progress in anti-HIV-1 therapy, current antiviral chemo-therapy still suffers from deleterious side effects and emerging drug resistance. Therefore, the development of novel antiviral drugs remains a crucial issue for the fight against AIDS. HIV-1 integrase is a key enzyme in the replication cycle of the retrovirus since it catalyzes the integration of the reverse transcribed viral DNA into the chromosomal DNA. Efforts to develop anti-integrase drugs started during the early nineties, culminating with the recent approval of Raltegravir. The discovery and the development of the styrylquinoline inhibitor class was an important step in the overall process. In this review we have described the key synthetic issues and the structure-activity relationship of this family of integrase inhibitors. Crystallographic and docking studies that shed light on their mechanism of action are also examined.
Also flagged:Tetrabenazineneurodegenerative disorderHuntingtinHDdopaminepathogenesis
Journal Article2010-04-26✓ 5 SnippetsWang H, Chen X, Li Y, Tang TS, Bezprozvanny I.
In-Text Gene Mentions
Abstract)
…Huntington's disease (HD) is a neurodegenerative disorder caused by a polyglutamine (polyQ) expansion in Huntingtin protein (Htt).…
Abstract)
…in Huntingtin protein (Htt).…
Introduction)
…amino-terminus of Huntingtin (Htt), a 350 kDa…
Introduction)
…polyQ expansion inHttexp leads to…
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…been assigned toHttexp , such…
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<h4>Background</h4>Huntington's disease (HD) is a neurodegenerative disorder caused by a polyglutamine (polyQ) expansion in Huntingtin protein (Htt). PolyQ expansion in Httexp causes selective degeneration of striatal medium spiny neurons (MSN) in HD patients. A number of previous studies suggested that dopamine signaling plays an important role in HD pathogenesis. A specific inhibitor of vesicular monoamine transporter (VMAT2) tetrabenazine (TBZ) has been recently approved by Food and Drug Administration for treatment of HD patients in the USA. TBZ acts by reducing dopaminergic input to the striatum.<h4>Results</h4>In previous studies we demonstrated that long-term feeding with TBZ (combined with L-Dopa) alleviated the motor deficits and reduced the striatal neuronal loss in the yeast artificial chromosome transgenic mouse model of HD (YAC128 mice). To further investigate a potential beneficial effects of TBZ for HD treatment, we here repeated TBZ evaluation in YAC128 mice starting TBZ treatment at 2 months of age ("early" TBZ group) and at 6 months of age ("late" TBZ group). In agreement with our previous studies, we found that both "early" and "late" TBZ treatments alleviated motor deficits and reduced striatal cell loss in YAC128 mice. In addition, we have been able to recapitulate and quantify depression-like symptoms in TBZ-treated mice, reminiscent of common side effects observed in HD patients taking TBZ.<h4>Conclusions</h4>Our results further support therapeutic value of TBZ for treatment of HD but also highlight the need to develop more specific dopamine antagonists which are less prone to side-effects.
The transcriptional repressor B lymphocyte-induced maturation protein-1 (BLIMP1) regulates gene expression and cell fate. The DNA motif bound by BLIMP1 in vitro overlaps with that of interferon regulatory factors (IRFs), which respond to inflammatory/immune signals. At such sites, BLIMP1 and IRFs can antagonistically regulate promoter activity. In vitro motif selection predicts that only a subset of BLIMP1 or IRF sites is subject to antagonistic regulation, but the extent to which antagonism occurs is unknown, since an unbiased assessment of BLIMP1 occupancy in vivo is lacking. To address this, we identified an extended set of promoters occupied by BLIMP1. Motif discovery and enrichment analysis demonstrate that multiple motif variants are required to capture BLIMP1 binding specificity. These are differentially associated with CpG content, leading to the observation that BLIMP1 DNA-binding is methylation sensitive. In occupied promoters, only a subset of BLIMP1 motifs overlap with IRF motifs. Conversely, a distinct subset of IRF motifs is not enriched amongst occupied promoters. Genes linked to occupied promoters containing overlapping BLIMP1/IRF motifs (e.g. AIM2, SP110, BTN3A3) are shown to constitute a dynamic target set which is preferentially activated by BLIMP1 knock-down. These data confirm and extend the competitive model of BLIMP1 and IRF interaction.
…Huntington's disease (HD) is caused by a dominant mutation in HTT, the HD gene.…
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…dominant mutation inHTT, the HD…
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…HTT…
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Huntington's disease (HD) is caused by a dominant mutation in HTT, the HD gene. This discovery opens possibilities for treatment based on silencing of the disease-causing allele or with compounds that reduce the production of disease-causing mRNA and/or protein. Although additional developments are needed related to the delivery of gene silencing and discovery and development of drugs that reduce disease-causing gene products, these treatments are predicted to be effective since they act by reducing the source of toxicity. The identification of therapies that act by blocking toxicity is conceptually more complicated, as this requires an accurate understanding of the cellular location and the specific molecular dysfunctions that cause the phenotypes of HD, which is not yet available. Though challenges remain, significant progress has been made. Effective disease-modifying treatments will soon be tested and may lead to disease-altering therapies.
Also flagged:OBFC1replicative senescencetelomeredyskeratosis congenitaidiopathic pulmonary fibrosisaplastic anemia
Journal Article2010-04-26✓ 1 SnippetLevy D, Neuhausen SL, Hunt SC, Kimura M, Hwang SJ, Chen W, Bis JC, Fitzpatrick AL, Smith E, Johnson AD, Gardner JP, Srinivasan SR, Schork N, Rotter JI, Herbig U, Psaty BM, Sastrasinh M, Murray SS, Vasan RS, Province MA, Glazer NL, Lu X, Cao X, Kronmal R, Mangino M, Soranzo N, Spector TD, Berenson GS, Aviv A.
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…TNFSF4…
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Telomeres are engaged in a host of cellular functions, and their length is regulated by multiple genes. Telomere shortening, in the course of somatic cell replication, ultimately leads to replicative senescence. In humans, rare mutations in genes that regulate telomere length have been identified in monogenic diseases such as dyskeratosis congenita and idiopathic pulmonary fibrosis, which are associated with shortened leukocyte telomere length (LTL) and increased risk for aplastic anemia. Shortened LTL is observed in a host of aging-related complex genetic diseases and is associated with diminished survival in the elderly. We report results of a genome-wide association study of LTL in a consortium of four observational studies (n = 3,417 participants with LTL and genome-wide genotyping). SNPs in the regions of the oligonucleotide/oligosaccharide-binding folds containing one gene (OBFC1; rs4387287; P = 3.9 x 10(-9)) and chemokine (C-X-C motif) receptor 4 gene (CXCR4; rs4452212; P = 2.9 x 10(-8)) were associated with LTL at a genome-wide significance level (P < 5 x 10(-8)). We attempted replication of the top SNPs at these loci through de novo genotyping of 1,893 additional individuals and in silico lookup in another observational study (n = 2,876), and we confirmed the association findings for OBFC1 but not CXCR4. In addition, we confirmed the telomerase RNA component (TERC) as a gene associated with LTL (P = 1.1 x 10(-5)). The identification of OBFC1 through genome-wide association as a locus for interindividual variation in LTL in the general population advances the understanding of telomere biology in humans and may provide insights into aging-related disorders linked to altered LTL dynamics.
Also flagged:cholesterolcoronary artery diseasemetabolismmonogenicobesityalcohol
Journal Article2010-04-26No SnippetsWeissglas-Volkov D, Pajukanta P.
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Plasma levels of HDL cholesterol (HDL-C) have a strong inherited basis with heritability estimates of 40-60%. The well-established inverse relationship between plasma HDL-C levels and the risk of coronary artery disease (CAD) has led to an extensive search for genetic factors influencing HDL-C concentrations. Over the past 30 years, candidate gene, genome-wide linkage, and most recently genome-wide association (GWA) studies have identified several genetic variations for plasma HDL-C levels. However, the functional role of several of these variants remains unknown, and they do not always correlate with CAD. In this review, we will first summarize what is known about HDL metabolism, monogenic disorders associated with both low and high HDL-C levels, and candidate gene studies. Then we will focus this review on recent genetic findings from the GWA studies and future strategies to elucidate the remaining substantial proportion of HDL-C heritability. Comprehensive investigation of the genetic factors conferring to low and high HDL-C levels using integrative approaches is important to unravel novel pathways and their relations to CAD, so that more effective means of diagnosis, treatment, and prevention will be identified.
Also flagged:HepcidinironerythropoiesismetabolismHaemochromatosis
Journal Article2010-04-26✓ 5 SnippetsMorán-Jiménez MJ, Méndez M, Santiago B, Rodríguez-García ME, Moreno-Carralero MI, Sánchez-Lucío AC, Grau M, Enríquez-de-Salamanca R.
…eostasis in haemochromatotic (Hfe(-/-)) and wild-type mice.<h4>…
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…iron concentrations inHfe(-/-) mice to normal…
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…liver of theseHfe(-/-) mice.…
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…erythropoiesis in eitherHfe(-/-) or wild-type mice…
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<h4>Background</h4>Iron is essential for mammalian metabolism and its cellular concentration is controlled by regulating its acquisition and storage. Haemochromatosis is a condition involving iron overload that is characterised by increased duodenal iron absorption and a progressive accumulation of iron in vital organs. Hepcidin is the main hormone that regulates iron homoestasis and it is secreted by the liver.<h4>Materials and methods</h4>We have studied how extended hepcidin administration affects the iron load status, plasma and tissue iron concentration, erythropoiesis and the expression of proteins involved on iron homeostasis in haemochromatotic (Hfe(-/-)) and wild-type mice.<h4>Results</h4>Hepcidin reverted the high plasma iron concentrations in Hfe(-/-) mice to normal values. The high concentration of hepatic iron was not altered in the liver of these Hfe(-/-) mice. Hepcidin administration did not disturb erythropoiesis in either Hfe(-/-) or wild-type mice and likewise, hepcidin did not modify the expression of any protein analysed in the liver, duodenum or spleen of Hfe(-/-) and wild-type mice. These data confirm that hepcidin administration diminishes plasma iron concentrations.<h4>Conclusion</h4>Treatment with sustained doses of hepcidin diminishes plasma iron concentrations in Hfe(-/-) mice.
Also flagged:Cyclooxygenase-1lipidprostanoidsCox-2creCKO
Journal Article2010-04-24No SnippetsPapanicolaou KN, Streicher JM, Ishikawa TO, Herschman H, Wang Y, Walsh K.
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Cyclooxygenase-1 and -2 are rate-limiting enzymes in the formation of a wide array of bioactive lipid mediators collectively known as prostanoids (prostaglandins, prostacyclins, and thromboxanes). Evidence from clinical trials shows that selective inhibition of the second isoenzyme (cyclooxygenase-2, or Cox-2) is associated with increased risk for serious cardiovascular events and findings from animal-based studies have suggested protective roles of Cox-2 for the heart. To further characterize the function of Cox-2 in the heart, mice with loxP sites flanking exons 4 and 5 of Cox-2 were rendered knockout specifically in cardiac myocytes (Cox-2 CKO mice) via cre-mediated recombination. Baseline cardiac performance of CKO mice remained unchanged and closely resembled that of control mice. Furthermore, myocardial infarct size induced after in vivo ischemia/reperfusion (I/R) injury was comparable between CKO and control mice. In addition, cardiac hypertrophy and function four weeks after transverse aortic constriction (TAC) was found to be similar between the two groups. Assessment of Cox-2 expression in purified adult cardiac cells isolated after I/R and TAC suggests that the dominant source of Cox-2 is found in the non-myocyte fraction. In conclusion, our animal-based analyses together with the cell-based observations portray a limited role of cardiomyocyte-produced Cox-2 at baseline and in the context of ischemic or hemodynamic challenge.
Also flagged:Cystamineneurodegenerative disorderpolyglutaminedeathantibodyHD
Journal Article2010-04-24✓ 4 SnippetsBortvedt SF, McLear JA, Messer A, Ahern-Rindell AJ, Wolfgang WJ.
In-Text Gene Mentions
Abstract)
…Huntington's disease (HD) is a lethal, neurodegenerative disorder caused by expansion of the polyglutamine repeat in the Huntingtin gene (HTT), leading to mutant protein misfolding, aggregation, and neuronal death.…
Abstract)
…transgene encoding the anti-httintracellular antibody (intrab…
Abstract)
…Huntingtin gene (HTT), leading to…
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…HTT…
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Huntington's disease (HD) is a lethal, neurodegenerative disorder caused by expansion of the polyglutamine repeat in the Huntingtin gene (HTT), leading to mutant protein misfolding, aggregation, and neuronal death. Feeding a Drosophila HD model cystamine, or expressing a transgene encoding the anti-htt intracellular antibody (intrabody) C4-scFv in the nervous system, demonstrated therapeutic potential, but suppression of pathology was incomplete. We hypothesized that a combinatorial approach entailing drug and intrabody administration could enhance rescue of HD pathology in flies and that timing of treatment would affect outcomes. Feeding cystamine to adult HD flies expressing the intrabody resulted in a significant, additional rescue of photoreceptor neurodegeneration, but no additional benefit in longevity. Feeding cystamine during both larval and adult stages produced the converse result: longevity was significantly improved, but increased photoreceptor survival was not. We conclude that cystamine-intrabody combination therapies can be effective, reducing neurodegeneration and prolonging survival, depending on administration protocols.
Also flagged:colon carcinomacolorectal cancertumorsnucleotidechromosomeTumor
Journal Article2010-04-23✓ 2 SnippetsLagerstedt KK, Kristiansson E, Lönnroth C, Andersson M, Iresjö BM, Gustafsson A, Hansson E, Kressner U, Nordgren S, Enlund F, Lundholm K.
In-Text Gene Mentions
Discussion)
…Thus, 40% of the aberrant bases in 3 out of 4 Dukes groups were located on chromosome 20, which makes it likely related to carcinogenesis and early invasiveness.19 DNA alterations on chromosome 20 have been reported by others indicating correlations between gains and transition from colon adenoma to carcinoma.20–23 Among altered genes on chromosome 20 in the present study were AURKA and CSE1L, which were also reported by others related to colorectal cancer.23,24 Thus, our results and conclusions agreed with findings reported by others based on genomic and transcriptomic information from different sources and patients,18 when our computations were performed on specific chromosomes.…
Discussion)
…were AURKA andCSE1L, which were also…
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<h4>Background</h4>Genetic and epigenetic alterations in colorectal cancer are numerous. However, it is difficult to judge whether such changes are primary or secondary to the appearance and progression of tumors. Therefore, the aim of the present study was to identify altered DNA regions with significant covariation to transcription alterations along colon cancer progression.<h4>Methods</h4>Tumor and normal colon tissue were obtained at primary operations from 24 patients selected by chance. DNA, RNA and microRNAs were extracted from the same biopsy material in all individuals and analyzed by oligo-nucleotide array-based comparative genomic hybridization (CGH), mRNA- and microRNA oligo-arrays. Statistical analyses were performed to assess statistical interactions (correlations, co-variations) between DNA copy number changes and significant alterations in gene and microRNA expression using appropriate parametric and non-parametric statistics.<h4>Results</h4>Main DNA alterations were located on chromosome 7, 8, 13 and 20. Tumor DNA copy number gain increased with tumor progression, significantly related to increased gene expression. Copy number loss was not observed in Dukes A tumors. There was no significant relationship between expressed genes and tumor progression across Dukes A-D tumors; and no relationship between tumor stage and the number of microRNAs with significantly altered expression. Interaction analyses identified overall 41 genes, which discriminated early Dukes A plus B tumors from late Dukes C plus D tumor; 28 of these genes remained with correlations between genomic and transcriptomic alterations in Dukes C plus D tumors and 17 in Dukes D. One microRNA (microR-663) showed interactions with DNA alterations in all Dukes A-D tumors.<h4>Conclusions</h4>Our modeling confirms that colon cancer progression is related to genomic instability and altered gene expression. However, early invasive tumor growth seemed rather related to transcriptomic alterations, where changes in microRNA may be an early phenomenon, and less to DNA copy number changes.
<h4>Background</h4>FibroTest and elastography have been validated as biomarkers of liver fibrosis in the most frequent chronic liver diseases and in the fibrosis screening of patients with diabetes. One challenge was to use them for estimating the prevalence of fibrosis, identifying independent risk factors and to propose screening strategies in the general population.<h4>Methods</h4>We prospectively studied 7,463 consecutive subjects aged 40 years or older. Subjects with presumed advanced fibrosis (FibroTest greater than 0.48) were re-investigated in a tertiary center.<h4>Results</h4>The sample characteristics were similar to those of the French population. FibroTest was interpretable in 99.6%. The prevalence of presumed fibrosis was 2.8%, (209/7,463), including cirrhosis in 0.3% (25/7,463); 105/209 (50%) subjects with presumed fibrosis accepted re-investigation. Fibrosis was confirmed in 50, still suspected in 27, indeterminate in 25 and not confirmed with false positive FibroTest or false negative elastography in 3 subjects. False negative rate of FibroTest estimated using elastography was 0.4% (3/766). The attributable causes for confirmed fibrosis were both alcoholic and nonalcoholic fatty liver disease (NAFLD) in 66%, NAFLD in 13%, alcohol in 9%, HCV in 6%, and other in 6%. Factors independently associated (all P < 0.003) with confirmed fibrosis were age, male gender, waist circumference, HCV antibody and alcohol consumption estimated using carbohydrate-deficient transferrin, enabling efficient screening-oriented strategies to be compared and proposed.<h4>Conclusions</h4>Biomarkers have permitted to estimate prevalence of advanced fibrosis around 2.8% in a general population aged 40 years or older, and several risk factors which may be used for the validation of selective or non-selective screening strategies.
Also flagged:SLC6A4to distressserotonin transporterserotonin
Journal Article2010-04-22✓ 1 Snippetvan Strien T, van der Zwaluw CS, Engels RC.
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Title)
…adolescents: a gene (SLC6A4/5-HTT) - depressive feelings…
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Eating in response to distress--i.e. emotional eating--is highly prevalent in (female) adults with binge eating, but has only a very low prevalence in young children. The present study addresses the emergence of emotional eating in adolescence in relation to depressive feelings. Because a reduction of food intake is considered the biologically natural response to distress, we tested whether the a-typical stress-response of emotional eating develops in interaction with genetic vulnerability. We hypothesized that the short allele of the 5-HTTLPR polymorphism in the serotonin transporter gene, which is associated with lower serotonin activity, would moderate the relation between depressive feelings and the increase in emotional eating, particularly in females. A sample of Dutch families with two adolescents was included in a longitudinal study with a four-year follow-up. A moderator effect of 5-HTTLPR genotype on the relation between depressive feelings and the increase in emotional eating was found in both sexes in the youngest siblings (n = 286). In the older siblings (n = 298), this specific moderator effect was only found in the girls. Younger adolescents and older adolescent girls showed a higher increase in emotional eating if they carried the 5-HTTLPR short allele. This is the first study that found support for a gene × depressive feelings interaction on emergence of emotional eating in (female) adolescents.
Journal Article2010-04-22✓ 3 SnippetsMichael M, Vehlow A, Navarro C, Krause M.
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Introduction)
…axon guidance receptorDCCand regulate cell…
Results)
…netrin receptor unc-40 /DCC[ 4 ].…
Results)
…this suggests that netrin/DCCsignaling induces Abl…
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<h4>Background</h4>Tight regulation of cell motility is essential for many physiological processes, such as formation of a functional nervous system and wound healing. Drosophila Abl negatively regulates the actin cytoskeleton effector protein Ena during neuronal development in flies, and it has been postulated that this may occur through an unknown intermediary. Lamellipodin (Lpd) regulates cell motility and recruits Ena/VASP proteins (Ena, Mena, VASP, EVL) to the leading edge of cells. However, the regulation of this recruitment has remained unsolved.<h4>Results</h4>Here we show that Lpd is a substrate of Abl kinases and binds to the Abl SH2 domain. Phosphorylation of Lpd positively regulates the interaction between Lpd and Ena/VASP proteins. Consistently, efficient recruitment of Mena and EVL to Lpd at the leading edge requires Abl kinases. Furthermore, transient Lpd phosphorylation by Abl kinases upon netrin-1 stimulation of primary cortical neurons positively correlates with an increase in Lpd-Mena coprecipitation. Lpd is also transiently phosphorylated by Abl kinases upon platelet-derived growth factor (PDGF) stimulation, regulates PDGF-induced dorsal ruffling of fibroblasts and axonal morphogenesis, and cooperates with c-Abl in an Ena/VASP-dependent manner.<h4>Conclusions</h4>Our findings suggest that Abl kinases positively regulate Lpd-Ena/VASP interaction, Ena/VASP recruitment to Lpd at the leading edge, and Lpd-Ena/VASP function in axonal morphogenesis and in PDGF-induced dorsal ruffling. Our data do not support the suggested negative regulatory role of Abl for Ena. Instead, we propose that Lpd is the hitherto unknown intermediary between Abl and Ena/VASP proteins.
Also flagged:obesitycolon cancer antigen 8TNKSTRF1MSRAmethionine sulfoxide reductase A
Journal Article2010-04-22✓ 5 SnippetsScherag A, Dina C, Hinney A, Vatin V, Scherag S, Vogel CI, Müller TD, Grallert H, Wichmann HE, Balkau B, Heude B, Jarvelin MR, Hartikainen AL, Levy-Marchal C, Weill J, Delplanque J, Körner A, Kiess W, Kovacs P, Rayner NW, Prokopenko I, McCarthy MI, Schäfer H, Jarick I, Boeing H, Fisher E, Reinehr T, Heinrich J, Rzehak P, Berdel D, Borte M, Biebermann H, Krude H, Rosskopf D, Rimmbach C, Rief W, Fromme T, Klingenspor M, Schürmann A, Schulz N, Nöthen MM, Mühleisen TW, Erbel R, Jöckel KH, Moebus S, Boes T, Illig T, Froguel P, Hebebrand J, Meyre D.
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Discussion)
…Leaving the hypothesis-free approach and focussing on known GWAS-based candidate markers, we were able to substantiate another four loci (NEGR1, SEC16B, BDNF and BCDIN3D) of the 16 obesity loci previously detected in GWAS [6], [9], [13], [14].…
Discussion)
…Not surprisingly, we confirmed the strongest effects (odds ratio for the obesity risk effect alleles of ∼1.4) reported for children and adolescents near FTO, MC4R and TMEM18[12] but also found support for variants near NEGR1, SEC16B, BDNF and BCDIN3D. Thus, one may speculate, that the genetic architecture in the paediatric extremely obese is in part similar to the BMI findings based mainly on adults from large population-based assessments (e.g. [13], [14]).…
Discussion)
…Thus, we demonstrate that the currently known major common variants related to obesity overlap to a substantial degree between children and adults confirming previous observations for FTO, MC4R, TMEM18, NEGR1[2], [6], [14] and extending this observation to SEC16B, BDNF and BCDIN3D; [13], [14].…
Meta-analyses of population-based genome-wide association studies (GWAS) in adults have recently led to the detection of new genetic loci for obesity. Here we aimed to discover additional obesity loci in extremely obese children and adolescents. We also investigated if these results generalize by estimating the effects of these obesity loci in adults and in population-based samples including both children and adults. We jointly analysed two GWAS of 2,258 individuals and followed-up the best, according to lowest p-values, 44 single nucleotide polymorphisms (SNP) from 21 genomic regions in 3,141 individuals. After this DISCOVERY step, we explored if the findings derived from the extremely obese children and adolescents (10 SNPs from 5 genomic regions) generalized to (i) the population level and (ii) to adults by genotyping another 31,182 individuals (GENERALIZATION step). Apart from previously identified FTO, MC4R, and TMEM18, we detected two new loci for obesity: one in SDCCAG8 (serologically defined colon cancer antigen 8 gene; p = 1.85x10(-8) in the DISCOVERY step) and one between TNKS (tankyrase, TRF1-interacting ankyrin-related ADP-ribose polymerase gene) and MSRA (methionine sulfoxide reductase A gene; p = 4.84x10(-7)), the latter finding being limited to children and adolescents as demonstrated in the GENERALIZATION step. The odds ratios for early-onset obesity were estimated at approximately 1.10 per risk allele for both loci. Interestingly, the TNKS/MSRA locus has recently been found to be associated with adult waist circumference. In summary, we have completed a meta-analysis of two GWAS which both focus on extremely obese children and adolescents and replicated our findings in a large followed-up data set. We observed that genetic variants in or near FTO, MC4R, TMEM18, SDCCAG8, and TNKS/MSRA were robustly associated with early-onset obesity. We conclude that the currently known major common variants related to obesity overlap to a substantial degree between children and adults.
Journal Article2010-04-22✓ 3 SnippetsSertel S, Eichhorn T, Simon CH, Plinkert PK, Johnson SW, Efferth T, Efferth T.
In-Text Gene Mentions
Results)
…cell proliferation (CSE1L), cell cycle…
Discussion)
…, RRAS ,CSE1L, HMGA1 and…
Discussion)
…present study revealsCSE1Las apoptosis-regulating gene…
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Development of novel therapy strategies is one of the major pressing topics of clinical oncology to overcome drug resistance of tumors. Artesunate (ART) is an anti-malarial drug, which also exerts profound cytotoxic activity towards cancer cells. We applied a gene-hunting approach using microarray-based transcriptome-wide mRNA expression profiling and COMPARE analyses. We identified a set of genes, whose expression was associated either with high IC50 values or low IC50 values for ART. Therefore, these genes may function as resistance or sensitivity factors for response of tumor cells towards ART. This viewpoint is conceivable for genes involved in ribosomal activity, drug transport, cellular antioxidant defense, apoptosis, cell proliferation, cell cycle progression etc. An investigation of underlying signal transduction by pathway analysis suggested a role of the signaling pathways related to tumor necrosis factor (TNF) and the tumor suppressor p53. On the other hand, there were genes without obvious functional link to cellular response to ART, such as genes involved in the survival of cochlear outer and inner hair cells etc. We proved the hypothesis that ART influences the activity of transcription factors regulating downstream genes involved or not involved in response of cancer cells towards ART. This would explain the identification of genes with and without obvious relation to the cytotoxic activity of ART by microarray and COMPARE analyses. By analysis of the binding motifs for the transcription factors c-Myc and Max, we indeed found that 53 of 56 genes contained one or more binding sites for c-Myc/Max upstream of the gene-location. We conclude that c-Myc and Max-mediated transcriptional control of gene expression might contribute to the therapeutic effects of ART in cancer cells, but may also confer unwanted side effects by affecting therapy-unrelated genes.
Over 10 years have passed since the first Sox gene was implicated in melanocyte development. Since then, we have discovered that SOX5, SOX9, SOX10 and SOX18 all participate as transcription factors that affect key melanocytic genes in both regulatory and modulatory fashions. Both SOX9 and SOX10 play major roles in the establishment and normal function of the melanocyte; SOX10 has been shown to heavily influence melanocyte development and SOX9 has been implicated in melanogenesis in the adult. Despite these advances, the precise cellular and molecular details of how these SOX proteins are regulated and interact during all stages of the melanocyte life cycle remain unknown. Improper regulation of SOX9 or SOX10 is also associated with cancerous transformation, and thus understanding the normal function of SOX proteins in the melanocyte will be key to revealing how these proteins contribute to melanoma.
Also flagged:vacuolesolute transporterscytoplasmicdetoxificationvacuolescytosol
Journal Article2010-04-21No SnippetsConn S, Gilliham M.
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<h4>Background</h4>Plants contain relatively few cell types, each contributing a specialized role in shaping plant function. With respect to plant nutrition, different cell types accumulate certain elements in varying amounts within their storage vacuole. The role and mechanisms underlying cell-specific distribution of elements in plants is poorly understood.<h4>Scope</h4>The phenomenon of cell-specific elemental accumulation has been briefly reviewed previously, but recent technological advances with the potential to probe mechanisms underlying elemental compartmentation have warranted an updated evaluation. We have taken this opportunity to catalogue many of the studies, and techniques used for, recording cell-specific compartmentation of particular elements. More importantly, we use three case-study elements (Ca, Cd and Na) to highlight the basis of such phenomena in terms of their physiological implications and underpinning mechanisms; we also link such distributions to the expression of known ion or solute transporters.<h4>Conclusions</h4>Element accumulation patterns are clearly defined by expression of key ion or solute transporters. Although the location of element accumulation is fairly robust, alterations in expression of certain solute transporters, through genetic modifications or by growth under stress, result in perturbations to these patterns. However, redundancy or induced pleiotropic expression effects may complicate attempts to characterize the pathways that lead to cell-specific elemental distribution. Accumulation of one element often has consequences on the accumulation of others, which seems to be driven largely to maintain vacuolar and cytoplasmic osmolarity and charge balance, and also serves as a detoxification mechanism. Altered cell-specific transcriptomics can be shown, in part, to explain some of this compensation.
Also flagged:cancerdivanillatestrivanillatesAurora AWEE1 kinasecancers
Journal Article2010-04-21No SnippetsLamoral-Theys D, Pottier L, Kerff F, Dufrasne F, Proutière F, Wauthoz N, Neven P, Ingrassia L, Antwerpen PV, Lefranc F, Gelbcke M, Pirotte B, Kraus JL, Nève J, Kornienko A, Kiss R, Dubois J.
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A series of 33 novel divanillates and trivanillates were synthesized and found to possess promising cytostatic rather than cytotoxic properties. Several compounds under study decreased by >50% the activity of Aurora A, B, and C, and WEE1 kinase activity at concentrations <10% of their IC(50) growth inhibitory ones, accounting, at least partly, for their cytostatic effects in cancer cells and to a lesser extent in normal cells. Compounds 6b and 13c represent interesting starting points for the development of cytostatic agents to combat cancers, which are naturally resistant to pro-apoptotic stimuli, including metastatic malignancies.
Axon pruning and neuronal cell death constitute two major regressive events that enable the establishment of fully mature brain architecture and connectivity. Although the cellular mechanisms for these two events are thought to be distinct, recent evidence has indicated the direct involvement of axon guidance molecules, including semaphorins, netrins, and ephrins, in controlling both processes. Here, we review how axon guidance cues regulate regressive events in paradigmatic models of neural development, from early control of apoptosis of neural progenitors, to later maintenance of neuronal survival and stereotyped pruning of axonal branches. These new findings are also discussed in the context of neural diseases and the potential links between axon pruning and degeneration.
Also flagged:myelin sheathaxonsaxonalmultiple sclerosisMSmyelin
Journal Article2010-04-20✓ 1 SnippetTaveggia C, Feltri ML, Wrabetz L.
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…DCC…
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The myelin sheath wraps large axons in both the CNS and the PNS, and is a key determinant of efficient axonal function and health. Myelin is targeted in a series of diseases, notably multiple sclerosis (MS). In MS, demyelination is associated with progressive axonal damage, which determines the level of patient disability. The few treatments that are available for combating myelin damage in MS and related disorders, which largely comprise anti-inflammatory drugs, only show limited efficacy in subsets of patients. More-effective treatment of myelin disorders will probably be accomplished by early intervention with combinatorial therapies that target inflammation and other processes-for example, signaling pathways that promote remyelination. Indeed, evidence suggests that such pathways might be impaired in pathology and, hence, contribute to the failure of remyelination in such diseases. In this article, we review the molecular basis of signaling pathways that regulate myelination in the CNS and PNS, with a focus on signals that affect differentiation of myelinating glia. We also discuss factors such as extracellular molecules that act as modulators of these pathways. Finally, we consider the few preclinical and clinical trials of agents that augment this signaling.
Also flagged:amyotrophic lateral sclerosisALSbone formationamino-terminalpeptidetype 1 collagen
Journal Article2010-04-20✓ 2 SnippetsFang F, Kwee LC, Allen KD, Umbach DM, Ye W, Watson M, Keller J, Oddone EZ, Sandler DP, Schmidt S, Kamel F.
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…hemochromatosis…
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The authors conducted a 2003-2007 case-control study including 184 cases and 194 controls to examine the association between blood lead and the risk of amyotrophic lateral sclerosis (ALS) among US veterans and to explore the influence on this association of bone turnover and genetic factors related to lead toxicokinetics. Blood lead, plasma biomarkers of bone formation (procollagen type 1 amino-terminal peptide (PINP)) and resorption (C-terminal telopeptides of type 1 collagen (CTX)), and the K59N polymorphism in the delta-aminolevulinic acid dehydratase gene, ALAD, were measured. Odds ratios and 95% confidence intervals for the association of blood lead with ALS were estimated with unconditional logistic regression after adjustment for age and bone turnover. Blood lead levels were higher among cases compared with controls (P < 0.0001, age adjusted). A doubling of blood lead was associated with a 1.9-fold increased risk of ALS (95% confidence interval: 1.3, 2.7) after adjustment for age and CTX. Additional adjustment for PINP did not alter the results. Significant lead-ALS associations were observed in substrata of PINP and CTX levels. The K59N polymorphism in the ALAD gene did not modify the lead-ALS association (P = 0.32). These results extend earlier findings by accounting for bone turnover in confirming the association between elevated blood lead level and higher risk of ALS.
Also flagged:Netrin-4laminin-related secretedaxon guidancetube formationfibroblast growth factor-2FGF-2
Journal Article2010-04-20✓ 1 SnippetLarrieu-Lahargue F, Welm AL, Thomas KR, Li DY.
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…DCC…
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Netrin-4, a laminin-related secreted protein is an axon guidance cue recently shown essential outside of the nervous system, regulating mammary and lung morphogenesis as well as blood vascular development. Here, we show that Netrin-4, at physiologic doses, induces proliferation, migration, adhesion, tube formation and survival of human lymphatic endothelial cells in vitro comparable to well-characterized lymphangiogenic factors fibroblast growth factor-2 (FGF-2), hepatocyte growth factor (HGF), vascular endothelial growth factor-A (VEGF-A), and vascular endothelial growth factor-C (VEGF-C). Netrin-4 stimulates phosphorylation of intracellular signaling components Akt, Erk and S6, and their specific inhibition antagonizes Netrin-4-induced proliferation. Although Netrin receptors Unc5B and neogenin, are expressed by human lymphatic endothelial cells, suppression of either or both does not suppress Netrin-4-promoted in vitro effects. In vivo, Netrin-4 induces growth of lymphatic and blood vessels in the skin of transgenic mice and in breast tumors. Its overexpression in human and mouse mammary carcinoma cancer cells leads to enhanced metastasis. Finally, Netrin-4 stimulates in vitro and in vivo lymphatic permeability by activating small GTPases and Src family kinases/FAK, and down-regulating tight junction proteins. Together, these data provide evidence that Netrin-4 is a lymphangiogenic factor contributing to tumor dissemination and represents a potential target to inhibit metastasis formation.
Also flagged:InterferonsIFNsclass II cytokinesimmune responsevirus infectionIFN
Journal Article2010-04-20✓ 1 SnippetTovey MG, Lallemand C.
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Introduction)
…the serotonin transporter (5-HTT) gene [ 111…
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Interferons (IFNs) are class II cytokines that are key components of the innate immune response to virus infection. Three IFN sub-families, type I, II, and III IFNs have been identified in man, Recombinant analogues of type I IFNs, in particular IFNα2 and IFNβ1, have found wide application for the treatment of chronic viral hepatitis and remitting relapsing multiple sclerosis respectively. Type II IFN, or IFN gamma, is used principally for the treatment of chronic granulomatous disease, while the recently discovered type III IFNs, also known as IFN lambda or IL-28/29, are currently being evaluated for the treatment of chronic viral hepatitis. IFNs are in general well tolerated and the most common adverse events observed with IFNα or IFNβ therapy are "flu-like" symptoms such as fever, headache, chills, and myalgia. Prolonged treatment is associated with more serious adverse events including leucopenia, thrombocytopenia, increased hepatic transaminases, and neuropsychiatric effects. Type I IFNs bind to high-affinity cell surface receptors, composed of two transmembrane polypeptides IFNAR1 and IFNAR2, resulting in activation of the Janus kinases Jak1 and Tyk2, phosphorylation and activation of the latent cytoplasmic signal transducers and activators of transcription (STAT1) and STAT2, formation of a transcription complex together with IRF9, and activation of a specific set of genes that encode the effector molecules responsible for mediating the biological activities of type I IFNs. Systemic administration of type I IFN results in activation of IFN receptors present on essentially all types of nucleated cells, including neurons and hematopoietic stem cells, in addition to target cells. This may well explain the wide spectrum of IFN associated toxicities. Recent reports suggest that certain polymorphisms in type I IFN signaling molecules are associated with IFN-induced neutropenia and thrombocytopenia in patients with chronic hepatitis C. IFNγ binds to a cell-surface receptor composed of two transmembrane polypeptides IFGR1 and IFGR2 resulting in activation of the Janus kinases Jak1 and Jak2, phosphorylation of STAT1, formation of STAT1 homodimers, and activation of a specific set of genes that encode the effector molecules responsible for mediating its biological activity. In common with type I IFNs, IFNγ receptors are ubiquitous and a number of the genes activated by IFNγ are also activated by type I IFNs that may well account for a spectrum of toxicities similar to that associated with type I IFNs including "flu-like" symptoms, neutropenia, thrombocytopenia, and increased hepatic transaminases. Although type III IFNs share the major components of the signal transduction pathway and activate a similar set of IFN-stimulated genes (ISGs) as type I IFNs, distribution of the IFNλ receptor is restricted to certain cell types suggesting that IFNλ therapy may be associated with a reduced spectrum of toxicities relative to type I or type II IFNs. Repeated administration of recombinant IFNs can cause in a break in immune tolerance to self-antigens in some patients resulting in the production of neutralizing antibodies (NABs) to the recombinant protein homologue. Appearance of NABs is associated with reduced pharmacokinetics, pharmacodynamics, and a reduced clinical response. The lack of cross-neutralization of IFNβ by anti-IFNα NABs and vice versa, undoubtedly accounts for the apparent lack of toxicity associated with the presence of anti-IFN NABs with the exception of relatively mild infusion/injection reactions.
Also flagged:neurological diseaseoxygenMitochondriaageingpathogenesismitochondrial
Journal Article2010-04-19✓ 5 Snippetsde Castro IP, Martins LM, Tufi R.
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Introduction)
…discovery of theHTTgene in 1993.…
Introduction)
…TheHTTgene product, Huntingtin…
Introduction)
…gene product, Huntingtin (HTT, Htt), is an…
Introduction)
…product, Huntingtin (HTT,Htt), is an extremely…
Introduction)
…AlthoughHttis mostly cytoplasmic,…
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The human brain is a highly complex organ with remarkable energy demands. Although it represents only 2% of the total body weight, it accounts for 20% of all oxygen consumption, reflecting its high rate of metabolic activity. Mitochondria have a crucial role in the supply of energy to the brain. Consequently, their deterioration can have important detrimental consequences on the function and plasticity of neurons, and is thought to have a pivotal role in ageing and in the pathogenesis of several neurological disorders. Owing to their inherent physiological functions, mitochondria are subjected to particularly high levels of stress and have evolved specific molecular quality-control mechanisms to maintain the mitochondrial components. Here, we review some of the most recent advances in the understanding of mitochondrial stress-control pathways, with a particular focus on how defects in such pathways might contribute to neurodegenerative disease.
Also flagged:phosphoglycerate mutase 1Amino AcidshepatomaPGAM1Cell proliferationliver cancer
Journal Article2010-04-19No SnippetsRen F, Wu H, Lei Y, Zhang H, Liu R, Zhao Y, Chen X, Zeng D, Tong A, Chen L, Wei Y, Huang C.
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<h4>Background</h4>Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide with poor prognosis due to resistance to conventional chemotherapy and limited efficacy of radiotherapy. There is an urgent need to develop novel biomarkers for early diagnosis, as well as to identify new drug targets for therapeutic interventions.<h4>Patients and methods</h4>54 paired HCC samples and 21 normal liver tissues were obtained from West China Hospital of Sichuan University. Informed consent was obtained from all the patients or their relatives prior to analysis, and the project was approved by the Institutional Ethics Committee of Sichuan University. Stable Isotope Labeling with Amino Acids in Cell Culture (SILAC)-based proteomics was employed to profile the differentially expressed proteins between a HepG2 human hepatoma cell line and an immortal hepatic cell line L02. Validation of PGAM1 expression was performed by semi-quantitative RT-PCR, immunoblot and immunohistochemistry using clinical samples. shRNA expressing plasmids specifically targeting PGAM1 were designed and constructed by GenePharma Corporation (Shanghai, China), and were utilized to silence expression of PGAM1 in vitro and in vivo. Cell proliferation was measured by a combination of colony formation assay and Ki67 staining. Apoptosis was examined by flow cytometry and TUNEL assay.<h4>Results</h4>A total of 63 dysregulated proteins were identified, including 51 up-regulated proteins, and 12 down-regulated proteins (over 2-fold, p < 0.01). Phosphoglycerate mutase 1 (PGAM1) was found markedly upregulated. Clinico-pathological analysis indicated that overexpression of PGAM1 was associated with 66.7% HCC, and strongly correlated with poor differentiation and decreased survival rates (p < 0.01). shRNAs-mediated repression of PGAM1 expression resulted in significant inhibition in liver cancer cell growth both in vitro and in vivo.<h4>Conclusion</h4>Our studies suggested that PGAM1 plays an important role in hepatocarcinogenesis, and should be a potential diagnostic biomarker, as well as an attractive therapeutic target for hepatocellular carcinoma.
Also flagged:LPCAT1phospholipidsynthesisRespiratory distress syndromedeathphosphatidylcholine
Journal Article2010-04-19✓ 1 SnippetBridges JP, Ikegami M, Brilli LL, Chen X, Mason RJ, Shannon JM.
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Respiratory distress syndrome (RDS), which is the leading cause of death in premature infants, is caused by surfactant deficiency. The most critical and abundant phospholipid in pulmonary surfactant is saturated phosphatidylcholine (SatPC), which is synthesized in alveolar type II cells de novo or by the deacylation-reacylation of existing phosphatidylcholine species. We recently cloned and partially characterized a mouse enzyme with characteristics of a lung lysophosphatidylcholine acyltransferase (LPCAT1) that we predicted would be involved in surfactant synthesis. Here, we describe our studies investigating whether LPCAT1 is required for pulmonary surfactant homeostasis. To address this issue, we generated mice bearing a hypomorphic allele of Lpcat1 (referred to herein as Lpcat1GT/GT mice) using a genetrap strategy. Newborn Lpcat1GT/GT mice showed varying perinatal mortality from respiratory failure, with affected animals demonstrating hallmarks of respiratory distress such as atelectasis and hyaline membranes. Lpcat1 mRNA levels were reduced in newborn Lpcat1GT/GT mice and directly correlated with SatPC content, LPCAT1 activity, and survival. Surfactant isolated from dead Lpcat1GT/GT mice failed to reduce minimum surface tension to wild-type levels. Collectively, these data demonstrate that full LPCAT1 activity is required to achieve the levels of SatPC essential for the transition to air breathing.
…We report the case of a 29 year old woman with a complex movement disorder syndrome due to the combination of coexisting pathological triplet repeat expansions of huntingtin and ATXN8 genes.…
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We report the case of a 29 year old woman with a complex movement disorder syndrome due to the combination of coexisting pathological triplet repeat expansions of huntingtin and ATXN8 genes. The disease course was characterized by mental disturbances including cognitive decline and changes in personality starting at the age of 12 years, followed by twisting motions, intentional tremor and gait ataxia. Later Parkinsonian symptoms of micrographia, bradykinesia, muscle rigidity and mental decline became dominant. Brain MRI showed hypoplasia of the nucleus caudatus and generalized atrophy; MR spectroscopy revealed a decrease of all typical metabolites except for an increased level of lactate and acetate. Therapeutic trials with pramipexole, ropinirole and tetrabenazine showed no benefit, while levetiracetam caused agitation and hallucinations. We discuss phenotype-genotype correlation and the rule of triplet repeat expansions of gene ATXN8.
…the serotonin transporter (5-HTT) is regulated by…
Abstract)
…region of the5-HTTgene (5-HTTLPR); however,…
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…the relation between5-HTTgenotype and 5-HTT…
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…5-HTT genotype and5-HTTradioligand binding in…
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Studies in vitro suggest that the expression of the serotonin transporter (5-HTT) is regulated by polymorphic variation in the promoter region of the 5-HTT gene (5-HTTLPR); however, results from human brain imaging studies examining the relation between 5-HTT genotype and 5-HTT radioligand binding in vivo have been inconsistent. This inconsistency could reflect small participant numbers or the use of sub-optimal radiotracer for measuring the 5-HTT. We used positron emission tomography in conjunction with the selective 5-HTT ligand [(11)C] DASB to examine the availability of the 5-HTT in seven brain regions in 63 healthy European caucasian volunteers who were genotyped for short (S) and long (L) variants (SLC6A4 and rs25531) of the 5-HTTLPR. [(11)C] DASB binding potential was not influenced by the allelic status of participants whether classified on a biallelic or triallelic basis in any of the regions studied. Our PET findings, in a relatively large sample with a near optimal radiotracer, suggest that 5-HTTLPR polymorphic variation does not affect the availability of 5-HTT to [(11)C] DASB binding in adult human brain. The reported impact of 5-HTTLPR polymorphic variation on emotional processing and vulnerability to depression are more likely therefore to be expressed through effects exerted during neurodevelopment.
Also flagged:IronHCtransferrin receptor 2TFR2HAMPHJV
Journal Article2010-04-18✓ 5 SnippetsEuropean Association For The Study Of The Liver.
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…EASL clinical practice guidelines for HFE hemochromatosis.…
Abstract)
…This Clinical Practice Guideline will therefore, focus on HFE-HC, while rarer forms of genetic iron overload recently attributed to pathogenic mutations of transferrin receptor 2, (TFR2), hepcidin (HAMP), hemojuvelin (HJV), or to a sub-type of ferroportin (FPN) mutations, on which limited and sparse clinical and epidemiologic data are available, will not be discussed.…
Iron overload in humans is associated with a variety of genetic and acquired conditions. Of these, HFE hemochromatosis (HFE-HC) is by far the most frequent and most well-defined inherited cause when considering epidemiological aspects and risks for iron-related morbidity and mortality. The majority of patients with HFE-HC are homozygotes for the C282Y polymorphism [1]. Without therapeutic intervention, there is a risk that iron overload will occur, with the potential for tissue damage and disease. While a specific genetic test now allows for the diagnosis of HFE-HC, the uncertainty in defining cases and disease burden, as well as the low phenotypic penetrance of C282Y homozygosity poses a number of clinical problems in the management of patients with HC. This Clinical Practice Guideline will therefore, focus on HFE-HC, while rarer forms of genetic iron overload recently attributed to pathogenic mutations of transferrin receptor 2, (TFR2), hepcidin (HAMP), hemojuvelin (HJV), or to a sub-type of ferroportin (FPN) mutations, on which limited and sparse clinical and epidemiologic data are available, will not be discussed. We have developed recommendations for the screening, diagnosis, and management of HFE-HC.
Also flagged:PIK3CAgastric carcinomacancercancersgastric cancertumours
Journal Article2010-04-16✓ 1 SnippetBarbi S, Cataldo I, De Manzoni G, Bersani S, Lamba S, Mattuzzi S, Bardelli A, Scarpa A.
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Introduction)
…TP73, APC ,DCC, FHIT and…
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<h4>Background</h4>PIK3CA is one of the genes most frequently mutated in human cancers and it is a potential target for personalized therapy. The aim of this study was to assess the frequency and type of PIK3CA mutations in gastric carcinoma and compare them with their clinical pathological correlates.<h4>Methods</h4>We analysed 264 gastric cancers, including 39 with microsatellite instability (MSI), for mutations in the two PIK3CA hotspots in exons 9 and 20 by direct sequencing of DNA obtained from microdissected cancer cells.<h4>Results</h4>The cases harbouring mutations were 42 (16%). All were heterozygous missense single base substitutions; the most common was H1047R (26/42; 62%) in exon 20 and the second was Q546K (4/42; 9.5%) in exon 9. All the mutated MSI cases (8/39) carried the H1047R mutation. No other association between PI3KCA mutations and their clinical pathological covariates was found. A metanalysis of the mutations occurring in the same regions presented in 27 publications showed that ratio between exon 20 and exon 9 prevalences was 0.6 (95% CI: 0.5 -0.8) for colon, 1.6 (95% CI: 1.1 -2.3) for breast, 2.7 (95% CI: 1.6 -4.9) for gastric and 4.1 (95% CI: 1.9 -10.3) for endometrial cancer.<h4>Conclusions</h4>The overall prevalence of PIK3CA mutations implies an important role for PIK3CA in gastric cancer. The lack of association with any clinical-pathological condition suggests that mutations in PIK3CA occur early in the development of cancer. The metanalysis showed that exon-selectivity is an important signature of cancer type reflecting different contexts in which tumours arise.
Also flagged:IHHMC4RobesityHypertensionDiabetes Mellitusorganization
Journal Article2010-04-16✓ 1 SnippetKang SJ, Chiang CW, Palmer CD, Tayo BO, Lettre G, Butler JL, Hackett R, Adeyemo AA, Guiducci C, Berzins I, Nguyen TT, Feng T, Luke A, Shriner D, Ardlie K, Rotimi C, Wilks R, Forrester T, McKenzie CA, Lyon HN, Cooper RS, Zhu X, Hirschhorn JN.
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Genome-wide association (GWA) studies have identified common variants that are associated with a variety of traits and diseases, but most studies have been performed in European-derived populations. Here, we describe the first genome-wide analyses of imputed genotype and copy number variants (CNVs) for anthropometric measures in African-derived populations: 1188 Nigerians from Igbo-Ora and Ibadan, Nigeria, and 743 African-Americans from Maywood, IL. To improve the reach of our study, we used imputation to estimate genotypes at approximately 2.1 million single-nucleotide polymorphisms (SNPs) and also tested CNVs for association. No SNPs or common CNVs reached a genome-wide significance level for association with height or body mass index (BMI), and the best signals from a meta-analysis of the two cohorts did not replicate in approximately 3700 African-Americans and Jamaicans. However, several loci previously confirmed in European populations showed evidence of replication in our GWA panel of African-derived populations, including variants near IHH and DLEU7 for height and MC4R for BMI. Analysis of global burden of rare CNVs suggested that lean individuals possess greater total burden of CNVs, but this finding was not supported in an independent European population. Our results suggest that there are not multiple loci with strong effects on anthropometric traits in African-derived populations and that sample sizes comparable to those needed in European GWA studies will be required to identify replicable associations. Meta-analysis of this data set with additional studies in African-ancestry populations will be helpful to improve power to detect novel associations.
Also flagged:IL-10OX40 ligandimmunosuppressionTNF-alphaLCcontact hypersensitivity
Journal Article2010-04-16No SnippetsYoshiki R, Kabashima K, Sakabe J, Sugita K, Bito T, Nakamura M, Malissen B, Tokura Y.
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The mechanism underlying the local UVB-induced immunosuppression is a central issue to be clarified in photoimmunology. There have been reported a considerable number of cells and factors that participate in the sensitization phase-dependent suppression, including Langerhans cells (LCs), regulatory T cells, IL-10, and TNF-alpha. The recent important finding that LC-depleted mice rather exhibit enhanced contact hypersensitivity responses urged us to re-evaluate the role of LCs along with dermal dendritic cells (dDCs) in the mechanism of UVB-induced immunosuppression. We studied the surface expression of OX40 ligand (OX40L) and the intracellular expression of IL-10 in LCs and dDCs from UVB-irradiated (300 mJ/cm(2)) skin of BALB/c mice and those migrating to the regional lymph nodes from UVB-irradiated, hapten-painted mice. In epidermal and dermal cell suspensions prepared from the UVB-irradiated skin, LCs expressed OX40L as well as CD86 and produced IL-10 at a higher level than Langerin(-) dDCs. The UVB-induced immunosuppression was attenuated by the administration of IL-10-neutralizing or OX40L-blocking Abs. In mice whose UVB-irradiated, hapten-painted skin was dissected 1 d after hapten application, the contact hypersensitivity response was restored, because this treatment allowed dDCs but not LCs to migrate to the draining lymph nodes. Moreover, LC-depleted mice by using Langerin-diphtheria toxin receptor-knocked-in mice showed impaired UVB-induced immunosuppression. These results suggest that IL-10-producing and OX40L-expressing LCs in the UVB-exposed skin are mandatory for the induction of Ag-specific regulatory T cells.
Journal Article2010-04-15No SnippetsCastets M, Mehlen P.
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Angiogenesis designates the formation of new vessels from preexisting ones, and occurs mainly during development. Tight control of this process is a prerequisite to avoid excess/defect in angiogenesis that are the underlying causes of several diseases conditions. Growing lines of evidences have indicated that some guidance cues are involved in regulation of vascular system elaboration, in addition to their role during nervous system development. In this way, netrin-1 has been involved in control of angiogenesis. However, a controversy has emerged regarding its action, since it was concluded from different studies that this protein was either a pro or an anti-angiogenic factor. Thus, netrin-1 role is still unclear. The aim of this review is to propose clues to explain previously reported discrepancies, in light of the dependence receptors model. Indeed, netrin-1 could likely favor angiogenesis, notably by blocking apoptosis induced by its unbound UNC5B receptor.
Also flagged:organizationcell adhesionpathogenesisepithelial cancersepidermal growth factorinsulin
Journal Article2010-04-15No SnippetsEritja N, Llobet D, Domingo M, Santacana M, Yeramian A, Matias-Guiu X, Dolcet X.
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Development of three-dimensional (3D) cultures that mimic in vivo tissue organization has a pivotal role in the investigation of the involvement of cell adhesion and polarity genes in the pathogenesis of epithelial cancers. Here we describe a novel 3D culture model with primary mouse endometrial epithelial cells. In this model, isolated endometrial epithelial cells develop single-lumened, polarized glandular structures resembling those observed in endometrial tissue. Our in vitro 3D culture model of endometrial glands requires the use of serum-free defined medium with only epidermal growth factor and insulin as growth supplements and 3% Matrigel as reconstituted extracellular matrix. Under these culture conditions, glands of epithelial cells displaying typical apicobasal polarity and proper positioning of tight and adherent junctions are formed by hollowing as early as 7 to 8 days in culture. Addition of the phosphatidylinositol 3-kinase inhibitor LY294002 completely inhibits bromodeoxyuridine incorporation and cyclinD1 expression, confirming that in vitro growth of endometrial glands depends on phosphatidylinositol 3-kinase/Akt signaling. To prove that our culture method is a good model to study endometrial carcinogenesis, we knocked down E-cadherin or phosphatase and tensin homolog expression by lentivirus-delivered short hairpin RNAs. Down-regulation of E-cadherin resulted in complete loss of epithelial cell polarity and glandular formation, whereas phosphatase and tensin homolog down-regulation resulted in increased proliferation of glandular epithelial cells. These properties indicate that our 3D culture model is suitable to study the effect of growth factors, drugs, and gene alterations in endometrial carcinogenesis and to study normal endometrial biology/physiology.
Also flagged:gastrinpeptide hormonecolorectal carcinomaGastrinsferric ionsglycine
Journal Article2010-04-15✓ 1 SnippetFerrand A, Lachal S, Bramante G, Kovac S, Shulkes A, Baldwin GS.
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…hemochromatosis…
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Precursors of the peptide hormone gastrin stimulate proliferation in the colorectal mucosa and promote the development of colorectal carcinoma. Gastrins bind two ferric ions selectively and with high affinity, and the biological activity of glycine-extended gastrin (Ggly) in vitro is dependent on the presence of ferric ions. The aim of the present study was to determine whether or not iron is required for biological activity of progastrin and Ggly in vivo. Rats that had undergone a colostomy were infused with Ggly, and proliferation was measured in the defunctioned rectal mucosa. Proliferation was also measured in the colonic mucosa of hGAS and MTI-Ggly mice, which, by definition, overexpress progastrin and Ggly, respectively. The requirement for iron was assessed by thrice-weekly injection of the chelating agent desferrioxamine (DFO). The proliferation index in the defunctioned rectal mucosa was significantly increased in the Ggly-infused rats, and the increase was significantly reduced after treatment with DFO. Treatment with DFO significantly reduced the crypt height and proliferation index in the colonic mucosa of hGAS and MTI-Ggly mice but had no effect on the same variables in wild-type mice. These observations are consistent with the hypothesis that the biological activity of progastrin and Ggly in vivo is dependent on the presence of ferric ions and further suggest that chelating agents may block the stimulatory effects of gastrin precursors in the development of colorectal carcinoma.
Also flagged:serotonin transporterSLC6A4systemic sclerosisSerotoninpulmonary arterial hypertensiontransporter
Journal Article2010-04-15✓ 1 SnippetWipff J, Bonnet P, Ruiz B, Dieude P, Avouac J, Tiev K, Hachulla E, Cracowski JL, Diot E, Sibilia J, Mouthon L, Meyer O, Kahan A, Boileau C, Allanore Y.
In-Text Gene Mentions
Abstract)
…transporter (SLC6A4 or5-HTT).…
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<h4>Objective</h4>Serotonin is a key contributing factor in pulmonary arterial hypertension (PAH) by inducing pulmonary arterial smooth muscle cell (PA-SMC) proliferation. This relates specifically to the internalization process in PA-SMC of the serotonin transporter (SLC6A4 or 5-HTT). A long (L)/short (S) (44 base pair insertion) functional polymorphism within the promoter of the transporter SLC6A4 gene has been reported to be associated with familial and idiopathic PAH. Our objective was to determine whether polymorphisms of SLC6A4 confer susceptibility to SSc and its vascular phenotype.<h4>Methods</h4>Three Tag single-nucleotide polymorphisms (SNP) (rs2066713, rs1042173, rs6354) chosen using Hapmap and linkage disequilibrium data were genotyped in a total cohort of 667 SSc patients (56 with PAH, 207 with digital ulcerations) and 447 controls. All individuals were of French Caucasian origin. L/S polymorphism genotyping was determined by polymerase chain reaction in a random subgroup of 364 SSc patients (34 with PAH, 138 with digital ulcerations) and 218 controls.<h4>Results</h4>Three polymorphisms (L/S, rs2066713, rs1042173) were in Hardy-Weinberg equilibrium in the control population, but rs6354 deviated. Allelic and genotypic frequencies for these 3 polymorphisms were similar in SSc patients and controls. Subphenotype analyses of subsets with PAH and digital ulceration did not detect any difference between SSc patients compared to controls.<h4>Conclusion</h4>These results from a large cohort of European Caucasian SSc patients do not support the implication of SLC6A4 in the pathogenesis of SSc and its vascular subphenotypes. However, serotonin pathways remain good candidates to contribute to the vasculopathy of SSc.
<h4>Background</h4>Prostaglandin E2 (PGE2) is involved in several chronic inflammatory diseases including periodontitis, which causes loss of the gingival tissue and alveolar bone supporting the teeth. We have previously shown that tumor necrosis factor alpha (TNFalpha) induces PGE2 synthesis in gingival fibroblasts. In this study we aimed to investigate the global gene expression profile of TNFalpha-stimulated primary human gingival fibroblasts, focusing on signal pathways related to the PGE2-synthesizing enzymes prostaglandin E synthases (PGES), as well as the upstream enzyme cyclooxygenase-2 (COX-2) and PGE2 production.<h4>Results</h4>Microarray and western blot analyses showed that the mRNA and protein expression of the inflammatory induced microsomal prostaglandin E synthase-1 (mPGES-1) was up-regulated by the cytokine TNFalpha, accompanied by enhanced expression of COX-2 and increased production of PGE2. In contrast, the expression of the isoenzymes microsomal prostaglandin E synthase-2 (mPGES-2) and cytosolic prostaglandin E synthase (cPGES) was unaffected by TNFalpha treatment. Using oligonucleotide microarray analysis in a time-course factorial design including time points 1, 3 and 6 h, differentially expressed genes in response to TNFalpha treatment were identified. Enrichment analysis of microarray data indicated two positively regulated signal transduction pathways: c-Jun N-terminal kinase (JNK) and Nuclear Factor-kappaB (NF-kappaB). To evaluate their involvement in the regulation of mPGES-1 and COX-2 expression, we used specific inhibitors as well as phosphorylation analysis. Phosphorylation analysis of JNK (T183/Y185) and NF-kappaB p65 (S536) showed increased phosphorylation in response to TNFalpha treatment, which was decreased by specific inhibitors of JNK (SP600125) and NF-kappaB (Bay 11-7082, Ro 106-9920). Inhibitors of JNK and NF-kappaB also decreased the TNFalpha-stimulated up-regulation of mPGES-1 and COX-2 as well as PGE2 production.<h4>Conclusion</h4>In the global gene expression profile, the enrichment analysis of microarray data identified the two signal transduction pathways JNK and NF-kappaB as positively regulated by the cytokine TNFalpha. Inhibition of these TNFalpha-activated signal pathways reduced the expression of mPGES-1 and COX-2 as well as their end product PGE2 in gingival fibroblasts. The involvement of the signal pathways JNK and NF-kappaB in the regulation of PGE2 induced by TNFalpha may suggest these two pathways as possible attractive targets in the chronic inflammatory disease periodontitis.
The accumulation of unfolded or misfolded proteins in the endoplasmic reticulum (ER) results in the condition called "ER stress," which induces the unfolded protein response (UPR), a complex cellular process that includes changes in expression of many genes. Failure to restore homeostasis in the ER is associated with human diseases. To identify the underlying changes in gene expression in response to ER stress, we induced ER stress in human B cells and then measured gene expression at ten time points. We followed up those results by studying cells from 60 unrelated people. We rediscovered genes that were known to play a role in the ER-stress response and uncovered several thousand genes that are not known to be involved. Two of these are VLDLR and INHBE, which showed significant increase in expression after ER stress in B cells and in primary fibroblasts. To study the links between UPR and disease susceptibility, we identified ER-stress-responsive genes that are associated with human diseases and assessed individual differences in the ER-stress response. Many of the UPR genes are associated with Mendelian disorders, such as Wolfram syndrome, and complex diseases, including amyotrophic lateral sclerosis and diabetes. Data from two independent samples showed extensive individual variability in ER-stress response. Additional analyses with monozygotic twins revealed significant correlations within twin pairs in their responses to ER stress, thus showing evidence for heritable variation among individuals. These results have implications for basic understanding of ER function and its role in disease susceptibility.
Also flagged:methylationglioblastomatumorshypermethylationgliomaglioblastomas
Journal Article2010-04-15✓ 1 SnippetNoushmehr H, Weisenberger DJ, Diefes K, Phillips HS, Pujara K, Berman BP, Pan F, Pelloski CE, Sulman EP, Bhat KP, Verhaak RG, Hoadley KA, Hayes DN, Perou CM, Schmidt HK, Ding L, Wilson RK, Van Den Berg D, Shen H, Bengtsson H, Neuvial P, Cope LM, Buckley J, Herman JG, Baylin SB, Laird PW, Aldape K, Cancer Genome Atlas Research Network.
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We have profiled promoter DNA methylation alterations in 272 glioblastoma tumors in the context of The Cancer Genome Atlas (TCGA). We found that a distinct subset of samples displays concerted hypermethylation at a large number of loci, indicating the existence of a glioma-CpG island methylator phenotype (G-CIMP). We validated G-CIMP in a set of non-TCGA glioblastomas and low-grade gliomas. G-CIMP tumors belong to the proneural subgroup, are more prevalent among lower-grade gliomas, display distinct copy-number alterations, and are tightly associated with IDH1 somatic mutations. Patients with G-CIMP tumors are younger at the time of diagnosis and experience significantly improved outcome. These findings identify G-CIMP as a distinct subset of human gliomas on molecular and clinical grounds.
<h4>Background</h4>Approximately 10% of attempted blood donations are not allowed because of low hemoglobin (Hb) deferral.<h4>Study design and methods</h4>Low Hb deferrals were tracked in more 715,000 whole blood donors at six blood centers across the United States. A multivariable logistic regression model was developed to comprehensively assess demographic correlates for low Hb deferral.<h4>Results</h4>Demographic factors significantly associated with low Hb deferral include female sex (11 times greater odds than males), increasing age in men (men over 80 have 29 times greater odds than men under 20), African American race (2-2.5 times greater odds than Caucasians), Hispanic ethnicity in women (1.29 times greater odds than Caucasian women), and weight in men (men under 124 pounds have 2.5 times greater odds than men over 200 pounds). Interestingly, increasing donation frequency is associated with decreased odds for low Hb deferral (women with one donation in the previous 12 months have two times greater odds than those with six donations).<h4>Conclusions</h4>Low Hb deferral is associated with female sex, older age, African American race/ethnicity, and lower body weight in men. An inverse association with donation frequency suggests a selection bias in favor of donors able to give more frequently. These data provide useful information that can be utilized to manage blood donors to limit low Hb deferrals and assist in policy decisions such as changing the Hb cutoff or permissible frequency of donation. They also generate hypotheses for new research of the causes of anemia in defined groups of donors.
Also flagged:iron regulator hormoneamino acidsmembranesHepcidinironmetabolism
Journal Article2010-04-15No SnippetsCampostrini N, Castagna A, Zaninotto F, Bedogna V, Tessitore N, Poli A, Martinelli N, Lupo A, Olivieri O, Girelli D.
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The hepatic iron regulator hormone hepcidin consists, in its mature form, of 25 amino acids, but two other isoforms, hepcidin-20 and hepcidin-22, have been reported, whose biological meaning remains poorly understood. We evaluated hepcidin isoforms in sera from 57 control and 54 chronic haemodialysis patients using a quantitative proteomic approach based on SELDI-TOF-MS. Patients had elevated serum levels of both hepcidin-25 and hepcidin-20 as compared to controls (geometric means: 7.52 versus 4.69 nM, and 4.06 versus 1.76 nM, resp., P < .05 for both). The clearance effects of a single dialysis session by different dialysis techniques and membranes were also investigated, showing an average reduction by 51.3% +/- 29.2% for hepcidin-25 and 34.2% +/- 28.4% for hepcidin-20 but only minor differences among the different dialysis modalities. Measurement of hepcidin isoforms through MS-based techniques can be a useful tool for better understanding of their biological role in hemodialysis patients and other clinical conditions.
Also flagged:Protein phosphatase 2Aautophagy-related kinaseaxon guidanceserine/threonine protein kinaseAtg1autophagy
Journal Article2010-04-14✓ 1 SnippetOgura K, Okada T, Mitani S, Gengyo-Ando K, Baillie DL, Kohara Y, Goshima Y.
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UNC-51 is a serine/threonine protein kinase conserved from yeast to humans. The yeast homolog Atg1 regulates autophagy (catabolic membrane trafficking) required for surviving starvation. In C. elegans, UNC-51 regulates the axon guidance of many neurons by a different mechanism than it and its homologs use for autophagy. UNC-51 regulates the subcellular localization (trafficking) of UNC-5, a receptor for the axon guidance molecule UNC-6/Netrin; however, the molecular details of the role for UNC-51 are largely unknown. Here, we report that UNC-51 physically interacts with LET-92, the catalytic subunit of serine/threonine protein phosphatase 2A (PP2A-C), which plays important roles in many cellular functions. A low allelic dose of LET-92 partially suppressed axon guidance defects of weak, but not severe, unc-51 mutants, and a low allelic dose of PP2A regulatory subunits A (PAA-1/PP2A-A) and B (SUR-6/PP2A-B) partially enhanced the weak unc-51 mutants. We also found that LET-92 can work cell-non-autonomously on axon guidance in neurons, and that LET-92 colocalized with UNC-51 in neurons. In addition, PP2A dephosphorylated phosphoproteins that had been phosphorylated by UNC-51. These results suggest that, by forming a complex, PP2A cooperates with UNC-51 to regulate axon guidance by regulating phosphorylation. This is the first report of a serine/threonine protein phosphatase functioning in axon guidance in vivo.
Also flagged:MLEElemental CarbonAmmoniumsiliconcarbonSodium Ion
Journal Article2010-04-14No SnippetsPeng RD, Bell ML.
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Time series studies of environmental exposures often involve comparing daily changes in a toxicant measured at a point in space with daily changes in an aggregate measure of health. Spatial misalignment of the exposure and response variables can bias the estimation of health risk, and the magnitude of this bias depends on the spatial variation of the exposure of interest. In air pollution epidemiology, there is an increasing focus on estimating the health effects of the chemical components of particulate matter (PM). One issue that is raised by this new focus is the spatial misalignment error introduced by the lack of spatial homogeneity in many of the PM components. Current approaches to estimating short-term health risks via time series modeling do not take into account the spatial properties of the chemical components and therefore could result in biased estimation of those risks. We present a spatial-temporal statistical model for quantifying spatial misalignment error and show how adjusted health risk estimates can be obtained using a regression calibration approach and a 2-stage Bayesian model. We apply our methods to a database containing information on hospital admissions, air pollution, and weather for 20 large urban counties in the United States.
Also flagged:gene expressionTMEM18FTOSH2B1obesityMTCH2
Journal Article2010-04-13✓ 3 SnippetsHolzapfel C, Grallert H, Huth C, Wahl S, Fischer B, Döring A, Rückert IM, Hinney A, Hebebrand J, Wichmann HE, Hauner H, Illig T, Heid IM.
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…near the genesNEGR1, TMEM18 ,…
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<h4>Background</h4>Data from meta-analyses of genome-wide association studies provided evidence for an association of polymorphisms with body mass index (BMI), and gene expression results indicated a role of these variants in the hypothalamus. It was consecutively hypothesized that these associations might be evoked by a modulation of nutritional intake or energy expenditure.<h4>Objective</h4>It was our aim to investigate the association of these genetic factors with BMI in a large homogenous population-based sample to explore the association of these polymorphisms with lifestyle factors related to nutritional intake or energy expenditure, and whether such lifestyle factors could be mediators of the detected single-nucleotide polymorphism (SNP)-association with BMI. It was a further aim to compare the proportion of BMI explained by genetic factors with the one explained by lifestyle factors.<h4>Design</h4>The association of seven polymorphisms in or near the genes NEGR1, TMEM18, MTCH2, FTO, MC4R, SH2B1 and KCTD15 was analyzed in 12,462 subjects from the population-based MONICA/KORA Augsburg study. Information on lifestyle factors was based on standardized questionnaires. For statistical analysis, regression-based models were used.<h4>Results</h4>The minor allele of polymorphism rs6548238 C>T (TMEM18) was associated with lower BMI (-0.418 kg m(-2), P=1.22 × 10(-8)), and of polymorphisms rs9935401 G>A (FTO) and rs7498665 A>G (SH2B1) with increased BMI (0.290 kg m(-2), P=2.85 × 10(-7) and 0.145 kg m(-2), P=9.83 × 10(-3)). The other polymorphisms were not significantly associated. Lifestyle factors were correlated with BMI and explained 0.037% of the BMI variance as compared with 0.006% of explained variance by the associated genetic factors. The genetic variants associated with BMI were not significantly associated with lifestyle factors and there was no evidence of lifestyle factors mediating the SNP-BMI association.<h4>Conclusions</h4>Our data first confirm the findings for TMEM18 with BMI in a single study on adults and also confirm the findings for FTO and SH2B1. There was no evidence for a direct SNP-lifestyle association.
Also flagged:neurotrophin-3digestionorganizationNT-3localizationlacZ
Journal Article2010-04-13✓ 1 SnippetFox EA, McAdams J.
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Vagal gastrointestinal (GI) afferents are essential for the regulation of eating, body weight, and digestion. However, their functional organization and the way that this develops are poorly understood. Neurotrophin-3 (NT-3) is crucial for the survival of vagal sensory neurons and is expressed in the developing GI tract, possibly contributing to their survival and to other aspects of vagal afferent development. The identification of the functions of this peripheral NT-3 thus requires a detailed understanding of the localization and timing of its expression in the developing GI tract. We have studied embryos and neonates expressing the lacZ reporter gene from the NT-3 locus and found that NT-3 is expressed predominantly in the smooth muscle of the outer GI wall of the stomach, intestines, and associated blood vessels and in the stomach lamina propria and esophageal epithelium. NT-3 expression has been detected in the mesenchyme of the GI wall by embryonic day 12.5 (E12.5) and becomes restricted to smooth muscle and lamina propria by E15.5, whereas its expression in blood vessels and esophageal epithelium is first observed at E15.5. Expression in most tissues is maintained at least until postnatal day 4. The lack of colocalization of beta-galactosidase and markers for myenteric ganglion cell types suggests that NT-3 is not expressed in these ganglia. Therefore, NT-3 expression in the GI tract is largely restricted to smooth muscle at ages when vagal axons grow into the GI tract, and when vagal mechanoreceptors form in smooth muscle, consistent with its role in these processes and in vagal sensory neuron survival.
Also flagged:Temozolomidetumorglial tumorshydrazidemalic acidantibody
Journal Article2010-04-13No SnippetsPatil R, Portilla-Arias J, Ding H, Inoue S, Konda B, Hu J, Wawrowsky KA, Shin PK, Black KL, Holler E, Ljubimova JY.
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<h4>Purpose</h4>Temozolomide (TMZ) is a pro-drug releasing a DNA alkylating agent that is the most effective drug to treat glial tumors when combined with radiation. TMZ is toxic, and therapeutic dosages are limited by severe side effects. Targeted delivery is thus needed to improve efficiency and reduce non-tumor tissue toxicity.<h4>Methods</h4>Multifunctional targetable nanoconjugates of TMZ hydrazide were synthesized using poly(β-L-malic acid) platform, which contained a targeting monoclonal antibody to transferrin receptor (TfR), trileucine (LLL), for pH-dependent endosomal membrane disruption, and PEG for protection.<h4>Results</h4>The water-soluble TMZ nanoconjugates had hydrodynamic diameters in the range of 6.5 to 14.8 nm and ζ potentials in the range of -6.3 to -17.7 mV. Fifty percent degradation in human plasma was observed in 40 h at 37°C. TMZ conjugated with polymer had a half-life of 5-7 h, compared with 1.8 h for free TMZ. The strongest reduction of human brain and breast cancer cell viability was obtained by versions of TMZ nanoconjugates containing LLL and anti-TfR antibody. TMZ-resistant cancer cell lines were sensitive to TMZ nanoconjugate treatment.<h4>Conclusions</h4>TMZ-polymer nanoconjugates entered the tumor cells by receptor-mediated endocytosis, effectively reduced cancer cell viability, and can potentially be used for targeted tumor treatment.
…This study identifies KLHL20-Cul3-ROC1 as an E3 ligase for DAPK ubiquitination and reveals a regulatory mechanism of DAPK, through blocking its accessibility to this E3 ligase, in IFN-induced apoptotic and autophagic death.…
Death-associated protein kinase (DAPK) was identified as a mediator of interferon (IFN)-induced cell death. How IFN controls DAPK activation remains largely unknown. Here, we identify the BTB-Kelch protein KLHL20 as a negative regulator of DAPK. KLHL20 binds DAPK and Cullin 3 (Cul3) via its Kelch-repeat domain and BTB domain, respectively. The KLHL20-Cul3-ROC1 E3 ligase complex promotes DAPK polyubiquitination, thereby inducing the proteasomal degradation of DAPK. Accordingly, depletion of KLHL20 diminishes DAPK ubiquitination and degradation. The KLHL20-mediated DAPK ubiquitination is suppressed in cells receiving IFN-alpha or IFN-gamma, which induces an enrichment/sequestration of KLHL20 in the PML nuclear bodies, thereby separating KLHL20 from DAPK. Consequently, IFN triggers the stabilization of DAPK. This mechanism of DAPK stabilization is crucial for determining IFN responsiveness of tumor cells and contributes to IFN-induced autophagy. This study identifies KLHL20-Cul3-ROC1 as an E3 ligase for DAPK ubiquitination and reveals a regulatory mechanism of DAPK, through blocking its accessibility to this E3 ligase, in IFN-induced apoptotic and autophagic death. Our findings may be relevant to the problem of IFN resistance in cancer therapy.
…Hyperferritinemia was associated with increased vascular damage only in patients with HFE genotypes associated with hepcidin upregulation by iron stores (p<0.0001), and serum hepcidin-25 was independently associated with carotid plaques (p=0.05).…
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…Hyperferritinemia was associated with increased vascular damage only in patients with HFE genotypes associated with hepcidin upregulation by iron stores (p<0.0001), and serum hepcidin-25 was independently associated with carotid plaques (p=0.05).<h4>Conclusion</h4>Ferritin levels, reflecting iron stores, are independent predictors of vascular damage in NAFLD.…
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…NAFLD, hemochromatosis gene (HFE) mutations by restriction…
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…in patients withHFEgenotypes associated with…
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…patients not carryingHFEmutations, and iron…
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<h4>Background and aims</h4>Increased ferritin and body iron stores are frequently observed in nonalcoholic fatty liver disease (NAFLD), associated with heightened susceptibility to vascular damage. Conflicting data have been reported on the role of iron in atherosclerosis, with recent data suggesting that excess iron induces vascular damage by increasing levels of the hormone hepcidin, which would determine iron trapping into macrophages, oxidative stress, and promotion of transformation into foam cells. Aim of this study was to investigate the relationship between iron status and cardiovascular damage in NAFLD.<h4>Methods and results</h4>Vascular damage was evaluated by common carotid arteries intima-media thickness (CC-IMT) measurement and plaque detection by ecocolor-doppler ultrasonography in 506 patients with clinical and ultrasonographic diagnosis of NAFLD, hemochromatosis gene (HFE) mutations by restriction analysis in 342 patients. Serum hepcidin-25 was measured by time-of-flight mass spectrometry in 143 patients. At multivariate analysis CC-IMT was associated with systolic blood pressure, glucose, LDL cholesterol, abdominal circumference, age, and ferritin (p=0.048). Carotid plaques were independently associated with age, ferritin, glucose, and hypertension. Ferritin reflected iron stores and metabolic syndrome components, but not inflammation or liver damage. Hyperferritinemia was associated with increased vascular damage only in patients with HFE genotypes associated with hepcidin upregulation by iron stores (p<0.0001), and serum hepcidin-25 was independently associated with carotid plaques (p=0.05).<h4>Conclusion</h4>Ferritin levels, reflecting iron stores, are independent predictors of vascular damage in NAFLD. The mechanism may involve upregulation of hepcidin by increased iron stores in patients not carrying HFE mutations, and iron compartmentalization into macrophages.
Also flagged:Mitochondrial disordersphosphorylationmitochondrialOXPHOS deficiencyMitochondriaorganelles
Journal Article2010-04-13✓ 5 SnippetsSmits P, Smeitink J, van den Heuvel L.
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…Mutations in the mitochondrial arginyl- and aspartyl-tRNA synthetases (RARS2 and DARS2) are associated with severe encephalopathy with pontocerebellar hypoplasia and LBSL (leukoencephalopathy with brain stem and spinal cord involvement and lactate elevation), respectively [16, 20, 23].…
Mitochondrial disorders are a heterogeneous group of often multisystemic and early fatal diseases, which are amongst the most common inherited human diseases. These disorders are caused by defects in the oxidative phosphorylation (OXPHOS) system, which comprises five multisubunit enzyme complexes encoded by both the nuclear and the mitochondrial genomes. Due to the multitude of proteins and intricacy of the processes required for a properly functioning OXPHOS system, identifying the genetic defect that underlies an OXPHOS deficiency is not an easy task, especially in the case of combined OXPHOS defects. In the present communication we give an extensive overview of the proteins and processes (in)directly involved in mitochondrial translation and the biogenesis of the OXPHOS system and their roles in combined OXPHOS deficiencies. This knowledge is important for further research into the genetic causes, with the ultimate goal to effectively prevent and cure these complex and often devastating disorders.
Also flagged:Gene expressionCDH17spasmolytic polypeptidegastric metaplasiasgastric cancerMUC13
Journal Article2010-04-13✓ 5 SnippetsLee HJ, Nam KT, Park HS, Kim MA, Lafleur BJ, Aburatani H, Yang HK, Kim WH, Goldenring JR.
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…gastric cancer tissues (MUC13, OLFM4, CDH17, KRT20, MUC5AC, LGALS4…
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…gastric cancer tissues (MUC13, OLFM4…
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…gastric cancer tissues (MUC13, OLFM4, CDH17, KRT20, MUC5AC, LGALS4, AKR1B10…
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…gastric cancer tissues (MUC13, OLFM4, CDH17…
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…gastric cancer tissues (MUC13, OLFM4, CDH17, KRT20…
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<h4>Background & aims</h4>Intestinal metaplasia (IM) and spasmolytic polypeptide-expressing metaplasia (SPEM) are precursors to gastric carcinogenesis. We sought to identify molecular biomarkers of gastric metaplasias and gastric cancer by gene expression profiling of metaplastic lesions from patients.<h4>Methods</h4>Complementary DNA microarray analysis was performed on IM and SPEM cells isolated from patient samples using laser capture microdissection. Up-regulated transcripts in metaplastic lesions were confirmed by immunostaining analysis in IM, SPEM, and gastric cancer tissues. Proteins that were highly expressed specifically in gastric cancer tissues were analyzed for their association with survival in a test set (n = 450) and a validation set (n = 502) of samples from gastric cancer patients.<h4>Results</h4>Compared with normal chief cells, 858 genes were differentially expressed in IM or SPEM samples. Immunostaining was detected for 12 proteins, including 3 new markers of IM (ACE2, LGALS4, AKR1B10) and 3 of SPEM (OLFM4, LYZ, DPCR1). Of 13 proteins expressed in IM or SPEM, 8 were expressed by 17%-50% of human gastric cancer tissues (MUC13, OLFM4, CDH17, KRT20, MUC5AC, LGALS4, AKR1B10, REG4). Expression of CDH17 or MUC13 correlated with patient survival in the test and validation sets. Multivariate analysis showed that CDH17 was an independent prognostic factor in patients with stage I or node-negative disease.<h4>Conclusions</h4>We identified several novel biomarkers for IM, SPEM, and gastric cancer using gene expression profiling of human metaplastic lesions. Expression of CDH17 and MUC13 was up-regulated in gastric cancer tissues. CDH17 is a promising prognostic marker for early stage gastric cancer.
Also flagged:gene expressioncognitionADshort-termcognitive declineaging
Journal Article2010-04-13✓ 1 SnippetGómez Ravetti M, Rosso OA, Berretta R, Moscato P.
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…MAZ interacts withDCC, the receptor for…
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<h4>Background</h4>Alzheimer's disease (AD) is characterized by a neurodegenerative progression that alters cognition. On a phenotypical level, cognition is evaluated by means of the MiniMental State Examination (MMSE) and the post-mortem examination of Neurofibrillary Tangle count (NFT) helps to confirm an AD diagnostic. The MMSE evaluates different aspects of cognition including orientation, short-term memory (retention and recall), attention and language. As there is a normal cognitive decline with aging, and death is the final state on which NFT can be counted, the identification of brain gene expression biomarkers from these phenotypical measures has been elusive.<h4>Methodology/principal findings</h4>We have reanalysed a microarray dataset contributed in 2004 by Blalock et al. of 31 samples corresponding to hippocampus gene expression from 22 AD subjects of varying degree of severity and 9 controls. Instead of only relying on correlations of gene expression with the associated MMSE and NFT measures, and by using modern bioinformatics methods based on information theory and combinatorial optimization, we uncovered a 1,372-probe gene expression signature that presents a high-consensus with established markers of progression in AD. The signature reveals alterations in calcium, insulin, phosphatidylinositol and wnt-signalling. Among the most correlated gene probes with AD severity we found those linked to synaptic function, neurofilament bundle assembly and neuronal plasticity.<h4>Conclusions/significance</h4>A transcription factors analysis of 1,372-probe signature reveals significant associations with the EGR/KROX family of proteins, MAZ, and E2F1. The gene homologous of EGR1, zif268, Egr-1 or Zenk, together with other members of the EGR family, are consolidating a key role in the neuronal plasticity in the brain. These results indicate a degree of commonality between putative genes involved in AD and prion-induced neurodegenerative processes that warrants further investigation.
Also flagged:GTP-binding proteinsGTPasesphosphoinositide-3 kinase enhancerPIKEPI3KAkt
Journal Article2010-04-13No SnippetsChan CB, Ye K.
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GTP-binding proteins are the molecular switches of numerous cellular functions, including migration, proliferation, and differentiation. In the past 10 years, we have characterized a novel class of GTPases called phosphoinositide-3 kinase enhancer (PIKE) that interacts with PI3K/Akt. In neurons, PIKE is involved in the protective mechanisms against neuroexcitotoxic insults by linking various receptors, such as mGluR1 and Unc5H2, to the PI3K cascade. Interestingly, the PIKE gene (CENTG1) is also amplified in a variety of human cancers and enhances Akt activity, leading to their resistance against apoptosis and invasion. It has also been demonstrated that PIKE is involved in endosome formation and nuclear protein accumulation. Thus, PIKE possesses multitudinous biological functions rather than solely acting as an apoptosis inhibitor. In this review, we will update our current knowledge of the role of PIKE in various cellular activities. Moreover, the functions of PIKE in peripheral tissues as revealed by the unique phenotypes in PIKE knock-out mice will be discussed as well.
Salmonella infections continue to cause substantial morbidity and mortality throughout the world. However, recent discoveries and new paradigms promise to lead to novel strategies to diagnose, treat, and prevent Salmonella infections. This review provides an update of the Salmonella field based on oral presentations given at the recent 3rd ASM Conference on Salmonella: Biology, Pathogenesis and Prevention.
Also flagged:SHANK3Schizophreniaautismneurodevelopmental disorderssynaptic scaffolding proteinschizoaffective disorder
Journal Article2010-04-12✓ 1 SnippetGauthier J, Champagne N, Lafrenière RG, Xiong L, Spiegelman D, Brustein E, Lapointe M, Peng H, Côté M, Noreau A, Hamdan FF, Addington AM, Rapoport JL, Delisi LE, Krebs MO, Joober R, Fathalli F, Mouaffak F, Haghighi AP, Néri C, Dubé MP, Samuels ME, Marineau C, Stone EA, Awadalla P, Barker PA, Carbonetto S, Drapeau P, Rouleau GA, S2D Team.
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Schizophrenia likely results from poorly understood genetic and environmental factors. We studied the gene encoding the synaptic protein SHANK3 in 285 controls and 185 schizophrenia patients with unaffected parents. Two de novo mutations (R1117X and R536W) were identified in two families, one being found in three affected brothers, suggesting germline mosaicism. Zebrafish and rat hippocampal neuron assays revealed behavior and differentiation defects resulting from the R1117X mutant. As mutations in SHANK3 were previously reported in autism, the occurrence of SHANK3 mutations in subjects with a schizophrenia phenotype suggests a molecular genetic link between these two neurodevelopmental disorders.
Also flagged:serotonin transportermethylationbehavioralsodiummood disorderspsychiatric illness
Journal Article2010-04-12✓ 5 SnippetsKinnally EL, Capitanio JP, Leibel R, Deng L, LeDuc C, Haghighi F, Mann JJ.
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…Consistent with human data, carriers of the low-expressing rh5-HTTLPR alleles exhibited higher mean 5-HTT CpG methylation, which was associated with lower PBMC 5-HTT expression.…
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…We hypothesized that peripheral blood mononuclear cell (PBMC) DNA methylation within an 800 bp cytosine-phosphate-guanosine (CpG) island that overlaps with the 5-HTT transcription initiation start site, a hypothesized model of the same genomic region in brain tissue, would mediate or moderate the effects of early life stress and a functional 5-HTT promoter polymorphism (rh5-HTTLPR) on two outcomes: PBMC 5-HTT expression and behavioral stress reactivity.…
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…5-HTT CpG methylation may be an important regulator of 5-HTT expression early in development and may contribute to the risk for mood disorders observed in 'high-risk'5-HTTLPR carriers.…
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…serotonin transporter (5-HTT) may contribute to…
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…and a functional5-HTTpromoter polymorphism (…
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Epigenetic mechanisms may moderate genetic and environmental risk (GxE) for mood disorders. We used an experimental rhesus macaque model of early life stress to test whether epigenetic regulation of serotonin transporter (5-HTT) may contribute to GxE interactions that influence behavior and emotion. We hypothesized that peripheral blood mononuclear cell (PBMC) DNA methylation within an 800 bp cytosine-phosphate-guanosine (CpG) island that overlaps with the 5-HTT transcription initiation start site, a hypothesized model of the same genomic region in brain tissue, would mediate or moderate the effects of early life stress and a functional 5-HTT promoter polymorphism (rh5-HTTLPR) on two outcomes: PBMC 5-HTT expression and behavioral stress reactivity. Eighty-seven infant rhesus macaques (3-4 months of age) were either mother reared in large social groups (n = 70) or nursery reared (n = 17). During a maternal/social separation, infants' blood was sampled and behavioral stress reactivity recorded. PBMC DNA and RNA samples were used to determine rh5-HTTLPR genotype, 5-HTT mRNA expression using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and 5-HTT CpG methylation status using sodium bisulfite pyrosequencing. Consistent with human data, carriers of the low-expressing rh5-HTTLPR alleles exhibited higher mean 5-HTT CpG methylation, which was associated with lower PBMC 5-HTT expression. Higher 5-HTT CpG methylation, but not rh5-HTTLPR genotype, exacerbated the effects of early life stress on behavioral stress reactivity in infants. 5-HTT CpG methylation may be an important regulator of 5-HTT expression early in development and may contribute to the risk for mood disorders observed in 'high-risk'5-HTTLPR carriers.
Also flagged:atrophyperiodontal diseasetitaniumagingpenicillinwater
Journal Article2010-04-12No SnippetsOshida Y, Tuna EB, Aktören O, Gençay K.
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Among various dental materials and their successful applications, a dental implant is a good example of the integrated system of science and technology involved in multiple disciplines including surface chemistry and physics, biomechanics, from macro-scale to nano-scale manufacturing technologies and surface engineering. As many other dental materials and devices, there are crucial requirements taken upon on dental implants systems, since surface of dental implants is directly in contact with vital hard/soft tissue and is subjected to chemical as well as mechanical bio-environments. Such requirements should, at least, include biological compatibility, mechanical compatibility, and morphological compatibility to surrounding vital tissues. In this review, based on carefully selected about 500 published articles, these requirements plus MRI compatibility are firstly reviewed, followed by surface texturing methods in details. Normally dental implants are placed to lost tooth/teeth location(s) in adult patients whose skeleton and bony growth have already completed. However, there are some controversial issues for placing dental implants in growing patients. This point has been, in most of dental articles, overlooked. This review, therefore, throws a deliberate sight on this point. Concluding this review, we are proposing a novel implant system that integrates materials science and up-dated surface technology to improve dental implant systems exhibiting bio- and mechano-functionalities.
We present the synthesis and selected physicochemical properties of several novel symmetrical and unsymmetrical alpha,omega-nucleobase mono- and bis-amide conjugated systems containing aliphatic, aromatic or saccharidic linkages. The final stage of the synthesis involves condensation of a subunit bearing carboxylic group with an amine subunit. 4-(4,6-Dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM) was found to be a particularly effective condensing agent. The subunits containing carboxylic groups were obtained by acidic hydrolysis of N-1 Michael adducts of uracils or N-9 Michael adducts of 6-chloropurine with methyl acrylate. The amines used were aliphatic/aromatic diamines, adenine, 5-substituted 1-(ω-aminoalkyl)uracils and 5'-amino-2',5'-dideoxythymidine. The title compounds may find application as antiprotozoal agents. Moreover, preliminary microscopy TEM studies of supramolecular behaviour showed that target molecules with bolaamphiphilic structures were capable of forming highly ordered assemblies, mainly nanofibres.
Also flagged:Tead2Tead3thymidine kinasedefectsTead1Tead4
Journal Article2010-04-12No SnippetsBhattaram P, Penzo-Méndez A, Sock E, Colmenares C, Kaneko KJ, Vassilev A, Depamphilis ML, Wegner M, Lefebvre V.
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During organogenesis, neural and mesenchymal progenitor cells give rise to many cell lineages, but their molecular requirements for self-renewal and lineage decisions are incompletely understood. In this study, we show that their survival critically relies on the redundantly acting SoxC transcription factors Sox4, Sox11 and Sox12. The more SoxC alleles that are deleted in mouse embryos, the more severe and widespread organ hypoplasia is. SoxC triple-null embryos die at midgestation unturned and tiny, with normal patterning and lineage specification, but with massively dying neural and mesenchymal progenitor cells. Specific inactivation of SoxC genes in neural and mesenchymal cells leads to selective apoptosis of these cells, suggesting SoxC cell-autonomous roles. Tead2 functionally interacts with SoxC genes in embryonic development, and is a direct target of SoxC proteins. SoxC genes therefore ensure neural and mesenchymal progenitor cell survival, and function in part by activating this transcriptional mediator of the Hippo signalling pathway.
Also flagged:autophagydegradationgeneticneurodegenerative disorderHDautophagic vacuoles
Journal Article2010-04-11✓ 5 SnippetsMartinez-Vicente M, Talloczy Z, Wong E, Tang G, Koga H, Kaushik S, de Vries R, Arias E, Harris S, Sulzer D, Cuervo AM.
In-Text Gene Mentions
Abstract)
…Alterations in macroautophagy, the main process responsible for bulk autophagic degradation, have been proposed to contribute to pathogenesis in Huntington's disease (HD), a genetic neurodegenerative disorder caused by an expanded polyglutamine tract in the huntingtin protein.…
Results)
…It is still possible that reversible changes in the oligomeric state of htt when associated to the APHs could contribute to the inefficient sequestration/engulfment of cytosolic cargo in HD.…
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…To determine the effect of expression of full size mutant htt on the activity of the autophagic system, we first compared total rates of intracellular protein degradation in embryonic fibroblasts (MEFs) from knock–in mice in which distinct CAG (glutamine) tracts (18 (control) or 111 (HD)) have been inserted in the exon–1 of the murine htt homolog to generate 18Qhtt and 111Qhtt mice, respectively18.…
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…Huntington’s disease (HD) is a hereditary neurodegenerative disease in which mutation in a protein, in this case the ubiquitously expressed protein huntingtin (htt), converts it into a pathogenic protein product2.…
Results)
…Lastly, the analysis of the proteolytic activity of disrupted lysosomes against a pool of radiolabeled cytosolic proteins revealed that lysosomes from HD cells displayed higher proteolytic efficiency than those from control cells, arguing against a primary defect in mature lysosomes due to the pathogenic htt mutation (Supplementary Fig. 4b).…
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Continuous turnover of intracellular components by autophagy is necessary to preserve cellular homeostasis in all tissues. Alterations in macroautophagy, the main process responsible for bulk autophagic degradation, have been proposed to contribute to pathogenesis in Huntington's disease (HD), a genetic neurodegenerative disorder caused by an expanded polyglutamine tract in the huntingtin protein. However, the precise mechanism behind macroautophagy malfunction in HD is poorly understood. In this work, using cellular and mouse models of HD and cells from humans with HD, we have identified a primary defect in the ability of autophagic vacuoles to recognize cytosolic cargo in HD cells. Autophagic vacuoles form at normal or even enhanced rates in HD cells and are adequately eliminated by lysosomes, but they fail to efficiently trap cytosolic cargo in their lumen. We propose that inefficient engulfment of cytosolic components by autophagosomes is responsible for their slower turnover, functional decay and accumulation inside HD cells.
Also flagged:serotonin transporterbehaviouralneuropsychiatric disordersc-Fos5psychopathologies
Journal Article2010-04-11✓ 4 SnippetsNonkes LJ, Tomson K, Maertin A, Dederen J, Maes JH, Homberg J.
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Abstract)
…the serotonin transporter (5-HTT).…
Abstract)
…5-HTTknockout (5-HTT(-/-)) rats…
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…5-HTT knockout (5-HTT(-/-)) rats and wild-type…
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…rats and wild-type (5-HTT(+/+)) controls were subjected…
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A disturbance in 5-HT signalling can lead to maladaptive and disruptive behavioural changes seen in neuropsychiatric disorders, potentially by 5-HT's role in cognitive control over behaviour. 5-HT levels are tightly controlled by the serotonin transporter (5-HTT). We and others have observed that 5-HTT availability affects reversal learning. Here we investigated the role of 5-HT in another type of cognitive control, which is the ability to use the value of expected outcomes to guide behaviour. 5-HTT knockout (5-HTT(-/-)) rats and wild-type (5-HTT(+/+)) controls were subjected to a Pavlovian reinforcer devaluation paradigm, which assesses the ability of an appetitive conditioned stimulus (CS) to gain access to the motivational properties of an upcoming aversive unconditioned stimulus (US). Neural correlates were evaluated using c-Fos immunohistochemistry, in brains of animals sacrificed 90min following the start of the probe test. Results show that conditioned responding was decreased in 5-HTT(+/+), but not 5-HTT(-/-), rats after US devaluation. In addition, OFC and basolateral amygdala (BLA) c-Fos immunoreactivity was increased in non-devalued 5-HTT(-/-) rats compared to non-devalued 5-HTT(+/+) rats. Whereas US devaluation increased c-Fos immunoreactivity in the OFC and BLA of 5-HTT(+/+) rats, there was no further increase in c-Fos immunoreactivity in the OFC and BLA of 5-HTT(-/-) rats. Taken together, 5-HTT(-/-) rats are unable to use the value of expected outcomes to guide behaviour, potentially due to over-activity of the OFC and BLA. Our findings suggest a new modulatory role of 5-HT in cognitive control over behaviour, which may have important implications for psychopathologies, like anxiety disorders and addiction.
Also flagged:neurological disordersHuntington'sAlzheimer's diseasesspinocerebellar ataxiasInositol trisphosphate receptor+ release
Journal Article2010-04-10✓ 1 SnippetFoskett JK.
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The modulation of cytoplasmic Ca2+ concentration by release from internal stores through the inositol trisphosphate receptor (InsP3R) Ca2+ release channel is a ubiquitous signaling system involved in the regulation of numerous processes. Because of its ubiquitous expression and roles in regulating diverse cell physiological processes, it is not surprising that the InsP3R has been implicated in a number of disease states. However, relatively few mutations in InsP3R genes have been identified to date. Here, I will discuss mutations in the type 1 InsP3R that have been discovered by analyses of human patients and mice with neurological disorders. In addition, I will highlight diseases caused by mutations in other genes, including Huntington's and Alzheimer's diseases and some spinocerebellar ataxias, where the mutant proteins have been found to exert strong influences on InsP3R function that may link InsP3R to disease pathogenesis.
Bcr-abl kinase inhibitors have provided proof of principal that targeted therapy holds great promise for the treatment of cancer. However, despite the success of these agents in treating chronic myelogenous leukemia (CML), the majority of patients continue to present with minimal residual disease contained within the bone marrow microenvironment. These clinical observations suggest that the bone marrow microenvironment may provide survival signals that contribute to the failure to eliminate minimal residual disease. The bone marrow microenvironment is comprised of multiple sub-domains which vary in cellular composition and gradients of soluble factors and matrix composition. Experimental evidence indicate that exposure of tumor cells to either bone marrow derived soluble factors or the extracellular matrix can confer a multi-drug resistance phenotype. Together, these data indicate that targeting such pathways may be a viable approach for increasing the efficacy of chemotherapy. Moreover, we propose that personalized medicine must go beyond understanding predictive models inherent to tumors but rather build predictive models that consider diversity in response due to interactions with the tumor microenvironment. Although review will focus on CML, understanding the contribution of the bone marrow microenvironment could contribute to rationale combination therapy in other types of leukemia, multiple myeloma and solid tumors which metastasize to the bone.
The architecture and functioning of the mammalian nervous system are partly based on the complexity of combinatorial gene expression in the developing brain that results in a tremendous diversity of neural cells. MicroRNAs are small non-coding RNAs that are particularly abundant in the brain and are emerging as influential regulators of neural gene expression. This review summarizes the recently discovered role of microRNAs in the development and maintenance of the nervous system. MicroRNAs are temporally expressed during neural differentiation, spatially regulated and embedded in molecular feedback loops that may contribute to the robustness of the neural networks.
Also flagged:SUMOylationtranslational modificationSUMOsmall ubiquitin-related modifierconjugationlysine
Journal Article2010-04-09No SnippetsWilkinson KA, Nakamura Y, Henley JM.
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The post-translational modification of proteins is critical for the spatial and temporal regulation of signalling cascades. This is especially important in the CNS where the processes affecting differentiation, growth, targeting and communication between neurones are highly complex and very tightly regulated. In recent years it has emerged that modification of proteins by members of the SUMO (small ubiquitin-related modifier) family of proteins play key roles in neuronal function. SUMOylation involves the covalent conjugation of a member of the SUMO family to lysine residues in target proteins. Multiple nuclear and perinuclear SUMOylation targets have been reported to be involved in nuclear organisation and transcriptional regulation. In addition, a growing number of extranuclear SUMO substrates have been identified that can have important acute effects on neuronal function. The SUMOylation of both intra- and extranuclear proteins have been implicated in a diverse array of processes that have far-reaching implications for neuronal function and pathophysiology. Here we review the current understanding of the targets and consequences of protein SUMOylation in the brain and examine its established and potential involvement in a wide range of neurological and neurodegenerative diseases.
Also flagged:axonaxonslocalizationunc-18secretionexocytosis
Journal Article2010-04-09No SnippetsAsakura T, Waga N, Ogura K, Goshima Y.
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UNC-6/Netrin is an evolutionarily conserved, secretory axon guidance molecule. In Caenorhabditis elegans, UNC-6 provides positional information to the axons of developing neurons, probably by establishing a concentration gradient from the ventral to the dorsal side of the animal. Although the proper localization of UNC-6 is important for accurate neuronal network formation, little is known about how its localization is regulated. Here, to examine the localization mechanism for UNC-6, we generated C. elegans expressing UNC-6 tagged with the fluorescent protein Venus and identified 13 genes, which are involved in the cellular localization of VenusUNC-6. For example, in unc-51, unc-14, and unc-104 mutants, the neurons showed an abnormal accumulation of VenusUNC-6 in the cell body and less than normal level of VenusUNC-6 in the axon. An aberrant accumulation of VenusUNC-6 in muscle cells was seen in unc-18 and unc-68 mutants. unc-51, unc-14, and unc-104 mutants also showed defects in the guidance of dorso-ventral axons, suggesting that the abnormal localization of UNC-6 disturbed the positional information it provides. We propose that these genes regulate the process of UNC-6 secretion: expression, maturation, sorting, transport, or exocytosis. Our findings provide novel insight into the localization mechanism of the axon guidance molecule UNC-6/Netrin.
Also flagged:SOX9transcription factorcartilage formationcampomelic dysplasiachondrocyte differentiationextracellular
Journal Article2010-04-09✓ 5 SnippetsOh CD, Maity SN, Lu JF, Zhang J, Liang S, Coustry F, de Crombrugghe B, Yasuda H.
In-Text Gene Mentions
Results)
…Table 3 lists the genes in which no SOX9 interaction sites were identified. This list includes the MyoD and Myogenin genes, which are master transcription factors for myoblast differentiation and are not expressed in chondrocytes. Other genes in this group include MMP13, those for several small leucine-rich proteoglycans, also the Wnt 3a, 5a, 7a, 9, Ihh and Shh genes. One surprise is that no clear SOX9-interaction site was found in the Sox6 gene, which together with Sox5, is required for overt chondrocyte differentiation and requires SOX9 for expression [8].…
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…SOX9, SOX5 andSOX6[19] .…
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…SOX9, SOX5 andSOX6were expressed at…
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…, Sox5 andSox6, and in…
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…found in theSox6gene, which together…
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<h4>Background</h4>Our previous work has provided strong evidence that the transcription factor SOX9 is completely needed for chondrogenic differentiation and cartilage formation acting as a "master switch" in this differentiation. Heterozygous mutations in SOX9 cause campomelic dysplasia, a severe skeletal dysmorphology syndrome in humans characterized by a generalized hypoplasia of endochondral bones. To obtain insights into the logic used by SOX9 to control a network of target genes in chondrocytes, we performed a ChIP-on-chip experiment using SOX9 antibodies.<h4>Methodology/principal findings</h4>The ChIP DNA was hybridized to a microarray, which covered 80 genes, many of which are involved in chondrocyte differentiation. Hybridization peaks were detected in a series of cartilage extracellular matrix (ECM) genes including Col2a1, Col11a2, Aggrecan and Cdrap as well as in genes for specific transcription factors and signaling molecules. Our results also showed SOX9 interaction sites in genes that code for proteins that enhance the transcriptional activity of SOX9. Interestingly, a strong SOX9 signal was also observed in genes such as Col1a1 and Osx, whose expression is strongly down regulated in chondrocytes but is high in osteoblasts. In the Col2a1 gene, in addition to an interaction site on a previously identified enhancer in intron 1, another strong interaction site was seen in intron 6. This site is free of nucleosomes specifically in chondrocytes suggesting an important role of this site on Col2a1 transcription regulation by SOX9.<h4>Conclusions/significance</h4>Our results provide a broad understanding of the strategies used by a "master" transcription factor of differentiation in control of the genetic program of chondrocytes.
Also flagged:serotonin-reuptake-transportermonoamine oxidasetranslationalmental illnessesanxietymental illness
Journal Article2010-04-09No SnippetsPine DS, Ernst M, Leibenluft E.
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<h4>Objective</h4>To place imaging-genetics research in the context of child psychiatry.<h4>Method</h4>A conceptual overview is provided, followed by discussion of specific research examples.<h4>Results</h4>Imaging-genetics research is described linking brain function to two specific genes, for the serotonin-reuptake-transporter protein and a monoamine oxidase enzyme. Work is then described on phenotype selection in imaging genetics.<h4>Conclusions</h4>Child psychiatry applications of imaging genetics are only beginning to emerge. The approach holds promise for advancing understandings of pathophysiology and therapeutics.
Also flagged:SIRT2neurodegenerative disorderpathogenesismetabolismsirtuin 2HD
Journal Article2010-04-08✓ 2 SnippetsLuthi-Carter R, Taylor DM, Pallos J, Lambert E, Amore A, Parker A, Moffitt H, Smith DL, Runne H, Gokce O, Kuhn A, Xiang Z, Maxwell MM, Reeves SA, Bates GP, Neri C, Thompson LM, Marsh JL, Kazantsev AG.
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Huntington's disease (HD), an incurable neurodegenerative disorder, has a complex pathogenesis including protein aggregation and the dysregulation of neuronal transcription and metabolism. Here, we demonstrate that inhibition of sirtuin 2 (SIRT2) achieves neuroprotection in cellular and invertebrate models of HD. Genetic or pharmacologic inhibition of SIRT2 in a striatal neuron model of HD resulted in gene expression changes including significant down-regulation of RNAs responsible for sterol biosynthesis. Whereas mutant huntingtin fragments increased sterols in neuronal cells, SIRT2 inhibition reduced sterol levels via decreased nuclear trafficking of SREBP-2. Importantly, manipulation of sterol biosynthesis at the transcriptional level mimicked SIRT2 inhibition, demonstrating that the metabolic effects of SIRT2 inhibition are sufficient to diminish mutant huntingtin toxicity. These data identify SIRT2 inhibition as a promising avenue for HD therapy and elucidate a unique mechanism of SIRT2-inhibitor-mediated neuroprotection. Furthermore, the ascertainment of SIRT2's role in regulating cellular metabolism demonstrates a central function shared with other sirtuin proteins.
Also flagged:Dosage compensationchromosomeX-chromosomegene expressiondosage compensation proteinschromosomes
Journal Article2010-04-08✓ 2 SnippetsMeyer BJ.
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Dosage compensation is a chromosome-wide regulatory process that balances X-chromosome gene expression between males and females that have different complements. Recent advances have clarified the molecular nature of the Caenorhabditis elegans sex-determination signal, which tallies X-chromosome number relative to the ploidy and controls both the choice of sexual fate and the process of dosage compensation. Dissecting the sex signal has revealed molecular mechanisms by which small quantitative differences in intracellular signals are translated into dramatically different developmental fates. Recent experiments have also revealed fundamental principles by which C. elegans dosage compensation proteins recognize and bind X chromosomes of XX embryos to reduce gene expression. Dosage compensation proteins function not only in a condensin complex specialized for regulating X-chromosome gene expression, but also in distinct condensin complexes that control other chromosome-wide processes: chromosome segregation and meiotic crossover recombination. The reshuffling of interchangeable molecular parts creates independent machines with similar architecture but distinct biological functions.
Also flagged:ovarian cancerepithelial ovarian carcinomaschromosomesgene expressionERBB2MYNN
Journal Article2010-04-08No SnippetsRamakrishna M, Williams LH, Boyle SE, Bearfoot JL, Sridhar A, Speed TP, Gorringe KL, Campbell IG.
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Ovarian cancer is a disease characterised by complex genomic rearrangements but the majority of the genes that are the target of these alterations remain unidentified. Cataloguing these target genes will provide useful insights into the disease etiology and may provide an opportunity to develop novel diagnostic and therapeutic interventions. High resolution genome wide copy number and matching expression data from 68 primary epithelial ovarian carcinomas of various histotypes was integrated to identify genes in regions of most frequent amplification with the strongest correlation with expression and copy number. Regions on chromosomes 3, 7, 8, and 20 were most frequently increased in copy number (> 40% of samples). Within these regions, 703/1370 (51%) unique gene expression probesets were differentially expressed when samples with gain were compared to samples without gain. 30% of these differentially expressed probesets also showed a strong positive correlation (r > or =0.6) between expression and copy number. We also identified 21 regions of high amplitude copy number gain, in which 32 known protein coding genes showed a strong positive correlation between expression and copy number. Overall, our data validates previously known ovarian cancer genes, such as ERBB2, and also identified novel potential drivers such as MYNN, PUF60 and TPX2.
…Huntington's disease (HD) is caused by a CAG repeat expansion in exon 1 of the HD gene resulting in a long polyglutamine tract in the N-terminus of the protein huntingtin.…
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Huntington's disease (HD) is caused by a CAG repeat expansion in exon 1 of the HD gene resulting in a long polyglutamine tract in the N-terminus of the protein huntingtin. Patients carrying the mutation display chorea in early stages followed by akinesia and sometimes dystonia in late stages. Other major symptoms include depression, anxiety, irritability or aggressive behavior, and apathy. Although many neuronal systems are affected, dysfunction and subsequent neurodegeneration in the basal ganglia and cortex are the most apparent pathologies. In HD, the primary hypothesis has been that there is an initial overactivity of glutamate neurotransmission that produces excitotoxicity followed by a series of complex changes that are different in the striatum and in the cortex. This review will focus on evidence for alterations in dopamine (DA)-glutamate interactions in HD, concentrating on the striatum and cortex. The most recent evidence points to decreases in DA and glutamate neurotransmission as the HD phenotype develops. However, there is some evidence for increased DA and glutamate functions that could be responsible for some of the early HD phenotype. Significant evidence indicates that glutamate and dopamine neurotransmission is affected in HD, compromising the fine balance in which DA modulates glutamate-induced excitation in the basal ganglia and cortex. Restoring the balance between glutamate and dopamine could be helpful to treat HD symptoms.
Also flagged:non-alcoholic fatty liver diseasesimple steatosisnon-alcoholic steatohepatitispathogenesisfatty acidmitochondria
Journal Article2010-04-07✓ 1 SnippetFerreira-Hermosillo A, Torres-Duran PV, Juarez-Oropeza MA.
In-Text Gene Mentions
Introduction)
…autoimmune diseases andhemochromatosis.…
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<h4>Introduction</h4>Non-alcoholic fatty liver diseases range from simple steatosis to non-alcoholic steatohepatitis. The "two hits" hypothesis is widely accepted for its pathogenesis: the first hit is an increased fat flux to the liver, which predisposes our patient to a second hit where increasing free fatty acid oxidation into the mitochondria leads to oxidative stress, lipoperoxidation and a chain reaction with increased ROS. Clinical indications include abdominal cramps, meteorism and fatigue. Most patients, however, are asymptomatic, and diagnosis is based on aminotransferase elevation and ultrasonography (or "brilliant liver"). Spirulina maxima has been experimentally proven to possess in vivo and in vitro hepatoprotective properties by maintaining the liver lipid profile. This case report evaluates the hepatoprotective effects of orally supplied Spirulina maxima.<h4>Case presentation</h4>Three Hispanic Mexican patients (a 43-year-old man, a 77-year-old man and a 44-year-old woman) underwent ultrasonography and were treated with 4.5 g/day of Spirulina maxima for three months. Their blood samples before and after the treatment determined triacylglycerols, total cholesterol, high-density lipoprotein cholesterol, alanine aminotransferase and low-density lipoprotein cholesterol levels. The results were assessed using ultrasound.<h4>Conclusion</h4>Treatment had therapeutic effects as evidenced by ultrasonography and the aminotransferase data. Hypolipidemic effects were also shown. We conclude that Spirulina maxima may be considered an alternative treatment for patients with non-alcoholic fatty liver diseases and dyslipidemic disorder.
Also flagged:autism spectrum disordersneurodevelopmental disordersgene expressionautismmethylationreverse transcription-
Journal Article2010-04-07No SnippetsSarachana T, Zhou R, Chen G, Manji HK, Hu VW.
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<h4>Background</h4>Autism spectrum disorders (ASD) are neurodevelopmental disorders characterized by abnormalities in reciprocal social interactions and language development and/or usage, and by restricted interests and repetitive behaviors. Differential gene expression of neurologically relevant genes in lymphoblastoid cell lines from monozygotic twins discordant in diagnosis or severity of autism suggested that epigenetic factors such as DNA methylation or microRNAs (miRNAs) may be involved in ASD.<h4>Methods</h4>Global miRNA expression profiling using lymphoblasts derived from these autistic twins and unaffected sibling controls was therefore performed using high-throughput miRNA microarray analysis. Selected differentially expressed miRNAs were confirmed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analysis, and the putative target genes of two of the confirmed miRNA were validated by knockdown and overexpression of the respective miRNAs.<h4>Results</h4>Differentially expressed miRNAs were found to target genes highly involved in neurological functions and disorders in addition to genes involved in gastrointestinal diseases, circadian rhythm signaling, as well as steroid hormone metabolism and receptor signaling. Novel network analyses of the putative target genes that were inversely expressed relative to the relevant miRNA in these same samples further revealed an association with ASD and other co-morbid disorders, including muscle and gastrointestinal diseases, as well as with biological functions implicated in ASD, such as memory and synaptic plasticity. Putative gene targets (ID3 and PLK2) of two RT-PCR-confirmed brain-specific miRNAs (hsa-miR-29b and hsa-miR-219-5p) were validated by miRNA overexpression or knockdown assays, respectively. Comparisons of these mRNA and miRNA expression levels between discordant twins and between case-control sib pairs show an inverse relationship, further suggesting that ID3 and PLK2 are in vivo targets of the respective miRNA. Interestingly, the up-regulation of miR-23a and down-regulation of miR-106b in this study reflected miRNA changes previously reported in post-mortem autistic cerebellum by Abu-Elneel et al. in 2008. This finding validates these differentially expressed miRNAs in neurological tissue from a different cohort as well as supports the use of the lymphoblasts as a surrogate to study miRNA expression in ASD.<h4>Conclusions</h4>Findings from this study strongly suggest that dysregulation of miRNA expression contributes to the observed alterations in gene expression and, in turn, may lead to the pathophysiological conditions underlying autism.
<h4>Purpose</h4>Corneal stroma extracellular matrix (ECM) glycosaminoglycans (GAGs) include keratan sulfate (KS), chondroitin sulfate A (CSA), and hyaluronic acid (HA). Embryonic corneal keratocytes and sensory nerve fibers grow and differentiate according to chemical cues they receive from the ECM. This study asked which of the proteins that may regulate keratocytes or corneal nerve growth cone immigration interact with corneal GAGs.<h4>Methods</h4>Biotinylated KS (bKS), CSA (bCSA), and HA (bHA) were prepared and used in microarray protocols to assess their interactions with 8268 proteins and a custom microarray of 85 extracellular epitopes of nerve growth-related proteins. Surface plasmon resonance (SPR) was performed with bKS and SLIT2, and their ka, kd, and KD were determined.<h4>Results</h4>Highly sulfated KS interacted with 217 microarray proteins, including 75 kinases, several membrane or secreted proteins, many cytoskeletal proteins, and many nerve function proteins. CSA interacted with 24 proteins, including 10 kinases and 2 cell surface proteins. HA interacted with 6 proteins, including several ECM-related structural proteins. Of 85 ECM nerve-related epitopes, KS bound 40 proteins, including SLIT, 2 ROBOs, 9 EPHs, 8 Ephrins (EFNs), 8 semaphorins (SEMAs), and 2 nerve growth factor receptors. CSA bound nine proteins, including ROBO2, 2 EPHs, 1 EFN, two SEMAs, and netrin 4. HA bound no ECM nerve-related epitopes. SPR confirmed that KS binds SLIT2 strongly. The KS core protein mimecan/osteoglycin bound 15 proteins.<h4>Conclusions</h4>Corneal stromal GAGs bind, and thus could alter the availability or conformation of, many proteins that may influence keratocyte and nerve growth cone behavior in the cornea.
Central nervous system (CNS) development, homeostasis, stress responses, and plasticity are all mediated by epigenetic mechanisms that modulate gene expression and promote selective deployment of functional gene networks in response to complex profiles of interoceptive and environmental signals. Thus, not surprisingly, disruptions of these epigenetic processes are implicated in the pathogenesis of a spectrum of neurological and psychiatric diseases. Epigenetic mechanisms involve chromatin remodeling by relatively generic complexes that catalyze DNA methylation and various types of histone modifications. There is increasing evidence that these complexes are directed to their sites of action by long non-protein-coding RNAs (lncRNAs), of which there are tens if not hundreds of thousands specified in the genome. LncRNAs are transcribed in complex intergenic, overlapping and antisense patterns relative to adjacent protein-coding genes, suggesting that many lncRNAs regulate the expression of these genes. LncRNAs also participate in a wide array of subcellular processes, including the formation and function of cellular organelles. Most lncRNAs are transcribed in a developmentally regulated and cell type specific manner, particularly in the CNS, wherein over half of all lncRNAs are expressed. While the numerous biological functions of lncRNAs are yet to be characterized fully, a number of recent studies suggest that lnRNAs are important for mediating cell identity. This function seems to be especially important for generating the enormous array of regional neuronal and glial cell subtypes that are present in the CNS. Further studies have also begun to elucidate additional roles played by lncRNAs in CNS processes, including homeostasis, stress responses and plasticity. Herein, we review emerging evidence that highlights the expression and function of lncRNAs in the CNS and suggests that lncRNA deregulation is an important factor in various CNS pathologies including neurodevelopmental, neurodegenerative and neuroimmunological disorders, primary brain tumors, and psychiatric diseases.
…A recently described full-length model of HD uses a BAC (bacterial artificial chromosome)-expressing mutant htt with 97 glutamine repeats (Gray et al., 2008b).…
Introduction)
…the HD gene,htt(huntingtin), is normally…
Introduction)
…forms of mutanthttin neurons.…
Introduction)
…expression of mutanthttin peripheral tissues…
Introduction)
…In neurons thehttprotein distribution is…
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The discovery of the HD (Huntington's disease) gene in 1993 led to the creation of genetic mouse models of the disease and opened the doors for mechanistic studies. In particular, the early changes and progression of the disease could be followed and examined systematically. The present review focuses on the contribution of these genetic mouse models to the understanding of functional changes in neurons as the HD phenotype progresses, and concentrates on two brain areas: the striatum, the site of most conspicuous pathology in HD, and the cortex, a site that is becoming increasingly important in understanding the widespread behavioural abnormalities. Mounting evidence points to synaptic abnormalities in communication between the cortex and striatum and cell-cell interactions as major determinants of HD symptoms, even in the absence of severe neuronal degeneration and death.
Also flagged:hepatocellular carcinomahepatitis B e antigenHBeAgcirrhosischronic hepatitiscore
Journal Article2010-04-07✓ 1 SnippetTong MJ, Hsu L, Hsien C, Kao JH, Durazo FA, Saab S, Blatt LM.
In-Text Gene Mentions
Methods)
…diseases such ashemochromatosisand autoimmune hepatitis,…
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<h4>Purpose</h4>Hepatitis B viral markers may be useful for predicting outcomes such as liver-related deaths or development of hepatocellular carcinoma. We determined the frequency of these markers in different clinical stages of chronic hepatitis B infection.<h4>Methods</h4>We compared baseline hepatitis B viral markers in 317 patients who were enrolled in a prospective study and identified the frequency of these tests in immune-tolerant (IT) patients, in inactive carriers, and in patients with either hepatitis B e antigen (HBeAg)-positive or HBeAg-negative chronic hepatitis or cirrhosis.<h4>Results</h4>IT patients were youngest (median age 27 years) and HBeAg-negative patients with cirrhosis were oldest (median age 58 years) (p = 0.03 to <0.0001). The male to female ratio was similar both in IT patients and in inactive carriers, but there was a male preponderance both in patients with chronic hepatitis and in patients with cirrhosis (p < 0.0001). The A1896 precore mutants were most prevalent in inactive carriers (36.4%) and HBeAg-negative patients with chronic hepatitis (38.8%; p < 0.0001), and the T1762/A1764 basal core promoter mutants were most often detected in HBeAg-negative patients with cirrhosis (65.1%; p = 0.02). Genotype A was detected only in 5.3% of IT patients, and genotype B was least often detected in both HBeAg-Positive patients with chronic hepatitis and cirrhosis (p = 0.03). The hepatitis B viral DNA levels were lowest in inactive carriers (2.69 log(10) IU/mL) and highest in IT patients (6.80 log(10) IU/mL; p = 0.02 to <0.0001). At follow-up, HBeAg-positive and HBeAg-negative patients with cirrhosis accounted for 57 of 64 (89.1%) liver-related deaths (p < 0.0001).<h4>Conclusion</h4>Differences in baseline hepatitis B viral markers were detected in patients in various clinical stages of hepatitis B virus infection. HBeAg-positive and HBeAg-negative patients with cirrhosis accounted for the majority of the liver-related fatalities.
<h4>Background</h4>In case-control studies of Europeans, heterozygosity for Arg702Trp(rs2066844), Gly908Arg(rs2066845) and Leu1007fsinsC(rs5743293) on the NOD2/CARD15 gene is associated with a 2-fold greater risk of Crohn disease, whereas homozygosity or compound heterozygosity is associated with a 17-fold greater risk. However, the importance of these genetic variants if identified in particular individuals within the general population is unknown. We undertook this study to estimate the penetrance of these variants in the general population.<h4>Methods</h4>We genotyped 43,596 individuals from the Danish general population followed between January 1976 and July 2007. Using a logistic regression model, we estimated the risk of Crohn disease in relation to variants of the NOD2/CARD15 gene in the general population. Penetrance was calculated as the fraction of participants in whom Crohn disease was diagnosed before age 50 years.<h4>Results</h4>In the general population, 89% of participants were noncarriers of the genetic variants of interest (n = 38,594), 11% were heterozygotes (n = 4838), and 0.4% were compound heterozygotes or homozygotes (n = 164). For Crohn disease, multifactorially adjusted odds ratios were 1.2 (95% confidence interval [CI] 0.8-1.9) for heterozygotes and 3.3 (95% CI 0.8-13.6) for compound heterozygotes and homozygotes combined, relative to noncarriers. Only 2 compound heterozygotes received a diagnosis of Crohn disease, and this disease was not diagnosed in any of the homozygotes. The penetrance at age 50 years of NOD2/CARD15 genetic variants of Crohn disease was 0.30% (95% CI 0.29%-0.31%) for heterozygotes and 1.5% (95% CI 1.4%-1.6%) for compound heterozygotes and homozygotes.<h4>Interpretation</h4>The penetrance of NOD2/CARD15 genetic variants in relation to risk of Crohn disease for this Danish population was lower than might have been expected from previous European case-control studies. This should be considered when advising healthy individuals in whom these genetic variants are identified.
…Several studies have shown, for example, that individuals carrying the S (short) allele of the serotonin transporter (5-HTT) gene-linked polymorphic region (5-HTTLPR) have an increased risk for major depression following exposure to stress in adulthood.…
Abstract)
…Heterozygous 5-HTT knockout mice exposed to high stress also showed significantly lower levels of serotonin turnover than wild-type littermates, selectively in the frontal cortex, which is a structure that is known to control fear and avoidance responses, and that is implicated in susceptibility to depression.…
Epidemiological evidence links exposure to stressful life events with increased risk for mental illness. However, there is significant individual variability in vulnerability to environmental risk factors, and genetic variation is thought to play a major role in determining who will become ill. Several studies have shown, for example, that individuals carrying the S (short) allele of the serotonin transporter (5-HTT) gene-linked polymorphic region (5-HTTLPR) have an increased risk for major depression following exposure to stress in adulthood. Identifying the molecular mechanisms underlying this gene-by-environment risk factor could help our understanding of the individual differences in resilience to stress. Here, we present a mouse model of the 5-HTT-by-stress risk factor. Wild-type and heterozygous 5-HTT knockout male mice were subjected to three weeks of chronic psychosocial stress. The 5-HTT genotype did not affect the physiological consequences of stress as measured by changes in body temperature, body weight gain and plasma corticosterone. However, when compared with wild-type littermates, heterozygous 5-HTT knockout mice experiencing high levels of stressful life events showed significantly depressed locomotor activity and increased social avoidance toward an unfamiliar male in a novel environment. Heterozygous 5-HTT knockout mice exposed to high stress also showed significantly lower levels of serotonin turnover than wild-type littermates, selectively in the frontal cortex, which is a structure that is known to control fear and avoidance responses, and that is implicated in susceptibility to depression. These data may serve as a useful animal model for better understanding the increased vulnerability to stress reported in individuals carrying the 5-HTTLPR S allele, and suggest that social avoidance represents a behavioral endophenotype of the interaction between 5-HTT and stress.
Also flagged:proteaseinfectionscoagulopathyDENV infectionsviral infectionsInter-α Inhibitor Proteins
Journal Article2010-04-06✓ 2 SnippetsKoraka P, Lim YP, Shin MD, Setiati TE, Mairuhu AT, van Gorp EC, Soemantri A, Osterhaus AD, Martina BE.
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…0.002), anti-thrombin III (ATIII, P = 0.024)…
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…(aPTT) and anti-coagulation (ATIII) factors ( Table…
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<h4>Background</h4>Inter-alpha inhibitor proteins (IaIp) belong to a family of protease inhibitors that are involved in the haemostatic and the vascular system. Dengue viruses (DENV) infections are characterized by coagulopathy and increased vascular permeability. In this study we measured the concentration of IaIp during DENV infections and evaluated its potential as a biomarker.<h4>Methods and findings</h4>Concentrations of IaIp were measured in patients with acute DENV infections using a quantitative, competitive enzyme linked immunoassay. Concentrations of IaIp measured in pediatric patients suffering from severe DENV infections were significantly lower than in healthy controls.<h4>Conclusions</h4>This is the first report to demonstrate changes in concentration of IaIp during viral infections. The data also highlight the potential of IaIp as a biological marker for severity of DENV infections.
Also flagged:phosphatidylinositol 3-kinasemammalian target of rapamycinPI3KmTORcancertype 2 diabetes
Journal Article2010-04-05✓ 1 SnippetPilot-Storck F, Chopin E, Rual JF, Baudot A, Dobrokhotov P, Robinson-Rechavi M, Brun C, Cusick ME, Hill DE, Schaeffer L, Vidal M, Goillot E.
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The phosphatidylinositol 3-kinase-mammalian target of rapamycin (PI3K-mTOR) pathway plays pivotal roles in cell survival, growth, and proliferation downstream of growth factors. Its perturbations are associated with cancer progression, type 2 diabetes, and neurological disorders. To better understand the mechanisms of action and regulation of this pathway, we initiated a large scale yeast two-hybrid screen for 33 components of the PI3K-mTOR pathway. Identification of 67 new interactions was followed by validation by co-affinity purification and exhaustive literature curation of existing information. We provide a nearly complete, functionally annotated interactome of 802 interactions for the PI3K-mTOR pathway. Our screen revealed a predominant place for glycogen synthase kinase-3 (GSK3) A and B and the AMP-activated protein kinase. In particular, we identified the deformed epidermal autoregulatory factor-1 (DEAF1) transcription factor as an interactor and in vitro substrate of GSK3A and GSK3B. Moreover, GSK3 inhibitors increased DEAF1 transcriptional activity on the 5-HT1A serotonin receptor promoter. We propose that DEAF1 may represent a therapeutic target of lithium and other GSK3 inhibitors used in bipolar disease and depression.
Also flagged:SynCAM 1growth conessynaptogenesismembrane proteinssynaptic cell adhesion molecule 1immunoglobulin
Journal Article2010-04-05✓ 1 SnippetStagi M, Fogel AI, Biederer T.
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Neuronal growth cones are highly motile structures that tip developing neurites and explore their surroundings before axo-dendritic contact and synaptogenesis. However, the membrane proteins organizing these processes remain insufficiently understood. Here we identify that the synaptic cell adhesion molecule 1 (SynCAM 1), an immunoglobulin superfamily member, is already expressed in developing neurons and localizes to their growth cones. Upon interaction of growth cones with target neurites, SynCAM 1 rapidly assembles at these contacts to form stable adhesive clusters. Synaptic markers can also be detected at these sites. Addressing the functions of SynCAM 1 in growth cones preceding contact, we determine that it is required and sufficient to restrict the number of active filopodia. Further, SynCAM 1 negatively regulates the morphological complexity of migrating growth cones. Focal adhesion kinase, a binding partner of SynCAM 1, is implicated in its morphogenetic activities. These results reveal that SynCAM 1 acts in developing neurons to shape migrating growth cones and contributes to the adhesive differentiation of their axo-dendritic contacts.
PURPOSE To analyze the frequency and associations with prognostic markers and outcome of mutations in IDH genes encoding isocitrate dehydrogenases in adult de novo cytogenetically normal acute myeloid leukemia (CN-AML). PATIENTS AND METHODS Diagnostic bone marrow or blood samples from 358 patients were analyzed for IDH1 and IDH2 mutations by DNA polymerase chain reaction amplification/sequencing. FLT3, NPM1, CEBPA, WT1, and MLL mutational analyses and gene- and microRNA-expression profiling were performed centrally. Results IDH mutations were found in 33% of the patients. IDH1 mutations were detected in 49 patients (14%; 47 with R132). IDH2 mutations, previously unreported in AML, were detected in 69 patients (19%; 13 with R172 and 56 with R140). R172 IDH2 mutations were mutually exclusive with all other prognostic mutations analyzed. Younger age (< 60 years), molecular low-risk (NPM1-mutated/FLT3-internal tandem duplication-negative) IDH1-mutated patients had shorter disease-free survival than molecular low-risk IDH1/IDH2-wild-type (wt) patients (P = .046). R172 IDH2-mutated patients had lower complete remission rates than IDH1/IDH2wt patients (P = .007). Distinctive microarray gene- and microRNA-expression profiles accurately predicted R172 IDH2 mutations. The highest expressed gene and microRNAs in R172 IDH2-mutated patients compared with the IDH1/IDH2wt patients were APP (previously associated with complex karyotype AML) and miR-1 and miR-133 (involved in embryonal stem-cell differentiation), respectively. CONCLUSION IDH1 and IDH2 mutations are recurrent in CN-AML and have an unfavorable impact on outcome. The R172 IDH2 mutations, previously unreported in AML, characterize a novel subset of CN-AML patients lacking other prognostic mutations and associate with unique gene- and microRNA-expression profiles that may lead to the discovery of novel, therapeutically targetable leukemogenic mechanisms.
Journal Article2010-04-05No SnippetsLiu Y, Shete S, Etzel CJ, Scheurer M, Alexiou G, Armstrong G, Tsavachidis S, Liang FW, Gilbert M, Aldape K, Armstrong T, Houlston R, Hosking F, Robertson L, Xiao Y, Wiencke J, Wrensch M, Andersson U, Melin BS, Bondy M.
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<h4>Purpose</h4>Glioblastoma (GBM) is the most common and aggressive type of glioma and has the poorest survival. However, a small percentage of patients with GBM survive well beyond the established median. Therefore, identifying the genetic variants that influence this small number of unusually long-term survivors may provide important insight into tumor biology and treatment.<h4>Patients and methods</h4>Among 590 patients with primary GBM, we evaluated associations of survival with the 100 top-ranking glioma susceptibility single nucleotide polymorphisms from our previous genome-wide association study using Cox regression models. We also compared differences in genetic variation between short-term survivors (STS; <or= 12 months) and long-term survivors (LTS; >or= 36 months), and explored classification and regression tree analysis for survival data. We tested results using two independent series totaling 543 GBMs.<h4>Results</h4>We identified LIG4 rs7325927 and BTBD2 rs11670188 as predictors of STS in GBM and CCDC26 rs10464870 and rs891835, HMGA2 rs1563834, and RTEL1 rs2297440 as predictors of LTS. Further survival tree analysis revealed that patients >or= 50 years old with LIG4 rs7325927 (V) had the worst survival (median survival time, 1.2 years) and exhibited the highest risk of death (hazard ratio, 17.53; 95% CI, 4.27 to 71.97) compared with younger patients with combined RTEL1 rs2297440 (V) and HMGA2 rs1563834 (V) genotypes (median survival time, 7.8 years).<h4>Conclusion</h4>Polymorphisms in the LIG4, BTBD2, HMGA2, and RTEL1 genes, which are involved in the double-strand break repair pathway, are associated with GBM survival.
Also flagged:OX40immune responsedeathcolitisFoxp3RAG
Journal Article2010-04-05No SnippetsGriseri T, Asquith M, Thompson C, Powrie F.
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The immune response in the gastrointestinal tract is a tightly controlled balance between effector and regulatory cell responses. Here, we have investigated the role of OX40 in influencing the balance between conventional T cells and Foxp3+ regulatory T (T reg) cells. Under steady-state conditions, OX40 was required by T reg cells for their accumulation in the colon, but not peripheral lymphoid organs. Strikingly, under inflammatory conditions OX40 played an essential role in T reg cell-mediated suppression of colitis. OX40(-/-) T reg cells showed reduced accumulation in the colon and peripheral lymphoid organs, resulting in their inability to keep pace with the effector response. In the absence of OX40 signaling, T reg cells underwent enhanced activation-induced cell death, indicating that OX40 delivers an important survival signal to T reg cells after activation. As OX40 also promoted the colitogenic Th1 response, its expression on T reg cells may be required for effective competition with OX40-dependent effector responses. These results newly identify a key role for OX40 in the homeostasis of intestinal Foxp3+ T reg cells and in suppression of colitis. These fi ndings should be taken into account when considering OX40 blockade for treatment of IBD.
Nearly two decades have passed since the discovery that the expansion of microsatellite trinucleotide repeats is responsible for a prominent class of neurological disorders, including Huntington disease and fragile X syndrome. These hereditary diseases are characterized by genetic anticipation or the intergenerational increase in disease severity accompanied by a decrease in age-of-onset. The revelation that the variable expansion of simple sequence repeats accounted for anticipation spawned a number of pathogenesis models and a flurry of studies designed to reveal the molecular events affected by these expansions. This work led to our current understanding that expansions in protein-coding regions result in extended homopolymeric amino acid tracts, often polyglutamine or polyQ, and deleterious protein gain-of-function effects. In contrast, expansions in noncoding regions cause RNA-mediated toxicity. However, the realization that the transcriptome is considerably more complex than previously imagined, as well as the emerging regulatory importance of antisense RNAs, has blurred this distinction. In this review, we summarize evidence for bidirectional transcription of microsatellite disease genes and discuss recent suggestions that some repeat expansions produce variable levels of both toxic RNAs and proteins that influence cell viability, disease penetrance and pathological severity.
Also flagged:antisocial personality disorderserotonin transporterSLC6A4Psychopathy
Journal Article2010-04-03✓ 2 SnippetsGarcia LF, Aluja A, Fibla J, Cuevas L, García O.
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…As the serotonin transporter gene (SLC6A4 or 5-HTT) is a key regulator of central serotonergic activity, several association studies between Antisocial Personality Disorder (APD) and the SLC6A4 polymorphisms have been conducted in the last decade.…
Abstract)
…gene (SLC6A4 or5-HTT) is a key…
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As the serotonin transporter gene (SLC6A4 or 5-HTT) is a key regulator of central serotonergic activity, several association studies between Antisocial Personality Disorder (APD) and the SLC6A4 polymorphisms have been conducted in the last decade. In the present study, the role of both 5-HTTLPR and 5-HTTVNTR polymorphisms of the SLC6A4 gene in APD is investigated. A sample of 147 male inmates was analyzed. APD was assessed by Aluja's Antisocial Personality Disorder Scale, a measure that correlates 0.73 with the dimensional score of DSM-IV APD and 0.62 with factor II of the Psychopathy Checklist-Revised. Inmates presenting both 5-HTTLPR S/S+S/L and 5-HTTVNTR 12/12 had a higher risk of being classified in the APD group (Odds ratio=3.48). The results also showed that the genotype and haplotype distribution was more dissimilar when extreme groups were compared with odds ratios up to 6.50. Our results supported that, in addition to the widely investigated 5-HTTLPR polymorphism, the 5-HTTVNTR polymorphism might be an interesting candidate for association studies with APD. Results also suggested that previous failures to replicate the association between serotonin transporter gene polymorphisms and APD, or similar phenotypes, could have been due to an under-representation of extremely high APD subjects in the samples analyzed.
Both hemojuvelin (HJV) and bone morphogenic protein-6 (BMP6) are essential for hepcidin expression. Hepcidin is the key peptide hormone in iron homeostasis, and is secreted predominantly by hepatocytes. HJV expression is detected in hepatocytes, as well as in skeletal and heart muscle. HJV binds BMP6 and increases hepcidin expression presumably by acting as a BMP co-receptor. We characterized the role of hepatocyte HJV in the regulation of BMP6 and hepcidin expression. In HJV-null (Hjv(-/-)) mice that have severe iron overload and marked suppression of hepcidin expression, we detected 4-fold higher hepatic BMP6 mRNA than in wild-type counterparts. These results indicate that Hjv(-/-) mice do not lack BMP6. Furthermore, iron depletion in Hjv(-/-) mice decreased hepatic BMP6 mRNA. Expression of HJV in hepatocytes of Hjv(-/-) mice using an AAV2/8 vector, increased hepatic hepcidin mRNA by 65-fold and phosphorylated Smad1/5/8 in the liver by about 2.5-fold. However, no significant change in BMP6 mRNA was detected in either the liver or the small intestine of these animals. Our results revealed a close correlation of hepatic BMP6 mRNA expression with hepatic iron-loading. Together, our data indicate that the regulation of hepatic BMP6 expression by iron is independent of HJV, and that expression of HJV in hepatocytes plays an essential role in hepcidin expression by potentiating the BMP6-mediated signaling.
Also flagged:homeodomainprostate-specific transcription factorepithelial cell proliferationcell growthprostate cancerbacterial prostatitis
Journal Article2010-04-02No SnippetsKhalili M, Mutton LN, Gurel B, Hicks JL, De Marzo AM, Bieberich CJ.
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NKX3.1 is a homeodomain protein that functions as a dosage sensitive prostate-specific transcription factor. Diminished NKX3.1 expression is associated with prostate epithelial cell proliferation in vitro and with increasing Gleason grade in patient samples. Mouse Nkx3.1 also functions as a negative regulator of prostate cell growth in prostate cancer models. Identifying biological and environmental factors that modulate NKX3.1 accumulation is therefore central to efforts aimed at elucidating prostate growth control mechanisms. To determine the effect of inflammation on Nxk3.1 accumulation, bacterial prostatitis was induced by intraurethral inoculation of a uropathogenic E. coli strain in mice. Nkx3.1 expression was profoundly reduced in infected prostate lobes and correlated with increased expression of a proliferation marker. Androgen receptor levels were also reduced in concert with Nkx3.1, and a marked increase in the basal cell marker p63 was observed. Analyses of the inflammatory infiltrate revealed a classic acute inflammatory response that attained characteristics of a chronic state within fourteen days postinoculation. Comparison of the four prostate lobes revealed clear differences in the extent of inflammation. These data demonstrate that acute inflammation in response to a bacterial agent in the prostate is associated with a significant diminution in the level of a key regulator of prostate cell proliferation. These observations provide a plausible mechanism whereby prostate inflammation may establish a local environment conducive to epithelial cell growth.
Also flagged:transcription factorbindingTFenhancer-associated coactivator protein Ep300p300SP1
Journal Article2010-04-02✓ 1 SnippetGotea V, Visel A, Westlund JM, Nobrega MA, Pennacchio LA, Ovcharenko I.
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Clustering of multiple transcription factor binding sites (TFBSs) for the same transcription factor (TF) is a common feature of cis-regulatory modules in invertebrate animals, but the occurrence of such homotypic clusters of TFBSs (HCTs) in the human genome has remained largely unknown. To explore whether HCTs are also common in human and other vertebrates, we used known binding motifs for vertebrate TFs and a hidden Markov model-based approach to detect HCTs in the human, mouse, chicken, and fugu genomes, and examined their association with cis-regulatory modules. We found that evolutionarily conserved HCTs occupy nearly 2% of the human genome, with experimental evidence for individual TFs supporting their binding to predicted HCTs. More than half of the promoters of human genes contain HCTs, with a distribution around the transcription start site in agreement with the experimental data from the ENCODE project. In addition, almost half of the 487 experimentally validated developmental enhancers contain them as well--a number more than 25-fold larger than expected by chance. We also found evidence of negative selection acting on TFBSs within HCTs, as the conservation of TFBSs is stronger than the conservation of sequences separating them. The important role of HCTs as components of developmental enhancers is additionally supported by a strong correlation between HCTs and the binding of the enhancer-associated coactivator protein Ep300 (also known as p300). Experimental validation of HCT-containing elements in both zebrafish and mouse suggest that HCTs could be used to predict both the presence of enhancers and their tissue specificity, and are thus a feature that can be effectively used in deciphering the gene regulatory code. In conclusion, our results indicate that HCTs are a pervasive feature of human cis-regulatory modules and suggest that they play an important role in gene regulation in the human and other vertebrate genomes.
<h4>Background</h4>Carbazole is a recalcitrant compound with a dioxin-like structure and possesses mutagenic and toxic activities. Bacteria respond to a xenobiotic by recruiting exogenous genes to establish a pathway to degrade the xenobiotic, which is necessary for their adaptation and survival. Usually, this process is mediated by mobile genetic elements such as plasmids, transposons, and insertion sequences.<h4>Findings</h4>The genes encoding the enzymes responsible for the degradation of carbazole to catechol via anthranilate were cloned, sequenced, and characterized from a carbazole-degrading Sphingomonas sp. strain XLDN2-5. The car gene cluster (carRAaBaBbCAc) and fdr gene were accompanied on both sides by two copies of IS6100 elements, and organized as IS6100::ISSsp1-ORF1-carRAaBaBbCAc-ORF8-IS6100-fdr-IS6100. Carbazole was converted by carbazole 1,9a-dioxygenase (CARDO, CarAaAcFdr), meta-cleavage enzyme (CarBaBb), and hydrolase (CarC) to anthranilate and 2-hydroxypenta-2,4-dienoate. The fdr gene encoded a novel ferredoxin reductase whose absence resulted in lower transformation activity of carbazole by CarAa and CarAc. The ant gene cluster (antRAcAdAbAa) which was involved in the conversion of anthranilate to catechol was also sandwiched between two IS6100 elements as IS6100-antRAcAdAbAa-IS6100. Anthranilate 1,2-dioxygenase (ANTDO) was composed of a reductase (AntAa), a ferredoxin (AntAb), and a two-subunit terminal oxygenase (AntAcAd). Reverse transcription-PCR results suggested that carAaBaBbCAc gene cluster, fdr, and antRAcAdAbAa gene cluster were induced when strain XLDN2-5 was exposed to carbazole. Expression of both CARDO and ANTDO in Escherichia coli required the presence of the natural reductases for full enzymatic activity.<h4>Conclusions/significance</h4>We predict that IS6100 might play an important role in the establishment of carbazole-degrading pathway, which endows the host to adapt to novel compounds in the environment. The organization of the car and ant genes in strain XLDN2-5 was unique, which showed strong evolutionary trail of gene recruitment mediated by IS6100 and presented a remarkable example of rearrangements and pathway establishments.
Intravenous immunoglobulins (IVIg) were first introduced in the middle of the twentieth century for the treatment of primary immunodeficiencies. In 1981, Paul Imbach noticed an improvement of immune-mediated thrombocytopenia, in patients receiving IVIg for immunodeficiencies. This opened a new era for the treatment of autoimmune conditions with IVIg. Since then, IVIg has become an important treatment option in a wide spectrum of diseases, including autoimmune and acute inflammatory conditions, most of them off-label (not included in the US Food and Drug Administration recommendation). A panel of immunologists and internists with experience in IVIg therapy reviewed the medical literature for published data concerning treatment with IVIg. The quality of evidence was assessed, and a summary of the available relevant literature in each disease was given. To our knowledge, this is the first all-inclusive comprehensive review, developed to assist the clinician when considering the use of IVIg in autoimmune diseases, immune deficiencies, and other conditions.
Also flagged:deathHuntington's diseasehypoxia inducible factor prolyl-4-hydroxylasesHIFmitochondrial3-nitropropionic acid
Journal Article2010-04-01✓ 1 SnippetNiatsetskaya Z, Basso M, Speer RE, McConoughey SJ, Coppola G, Ma TC, Ratan RR.
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…htt…
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Mitochondrial dysfunction is a central feature of a number of acute and chronic neurodegenerative conditions, but clinically approved therapeutic interventions are only just emerging. Here we demonstrate the potential clinical utility of low molecular weight inhibitors of the hypoxia inducible factor prolyl-4-hydroxylases (HIF PHDs) in preventing mitochondrial toxin-induced cell death in mouse striatal neurons that express a "knock-in" mutant Huntingtin allele. Protection from 3-nitropropionic acid (3-NP, a complex II inhibitor)-induced toxicity by HIF PHD inhibition occurs without rescue of succinate dehydrogenase activity. Although HIF-1alpha mRNA is dramatically induced by mutant huntingtin, HIF-1alpha depletion by short interfering RNAs (siRNA) does not affect steady-state viability or protection from 3-NP-induced death by HIF PHD inhibitors in these cells. Moreover, 3-NP-induced complex II inhibition in control or mutant striatal neurons does not lead to activation of HIF-dependent transcription. HIF PHD inhibition also protects cortical neurons from 3-NP-induced cytotoxicity. Protection of cortical neurons by HIF PHD inhibition correlates with enhanced VEGF but not PGC-1alpha gene expression. Together, these findings suggest that HIF PHD inhibitors are promising candidates for preventing cell death in conditions such as Huntington's disease and Alzheimer's disease that are associated with metabolic stress in the central nervous system.
Primitive marrow lineage-negative rhodamine low and Hoechst low (LRH) stem cells isolated on the basis of quiescence respond to the cytokines thrombopoietin, FLT3L, and steel factor by synchronously progressing through cell cycle. We have now profiled the mRNA expression, as determined by real-time RT-PCR, of 47 hematopoietic or cell cycle-related genes, focusing on the variations in the cell cycle regulators with cycle transit. LRH stem cells, at isolation, showed expression of all interrogated genes, but at relatively low levels. In our studies, there was a good deal of consistency with regard to cell cycle regulatory genes involved in the G1/S progression point of LRH murine stem cells. The observed pattern of expression of cyclin A2 is consistent with actions at these phases of cell cycle. Minimal elevations were seen at 16 h with higher elevations at 24, 32, 40, and 48 h times encompassing S, G2, and M phases. CDK2 expression pattern was also consistent with a role in G1/S transition with a modest elevation at 24 h and more substantial elevation at 32 h. The observed pattern of expression of cyclin F mRNA with marked elevations at 16-40 h was also consistent with actions in S and G2 phases. Cyclin D1 expression pattern was less consistent with its known role in G1 progression. The alterations in multiple other cell cycle regulators were consistent with previous information obtained in other cell systems. The cycle regulatory mechanics appears to be preserved across broad ranges of cell types.
Also flagged:childhood neglectsubstance abuseserotoninneglectcortisoladrenocorticotropic hormone
Journal Article2010-04-01✓ 5 SnippetsGerra G, Zaimovic A, Castaldini L, Garofano L, Manfredini M, Somaini L, Leonardi C, Gerra ML, Donnini C.
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Abstract)
…Higher frequency of the 5-HTT SS genotype seems to be associated with an increased susceptibility to use illegal psychotropic drugs among the adolescents.…
Title)
…Relevance of perceived childhood neglect, 5-HTT gene variants and hypothalamus-pituitary-adrenal axis dysregulation to substance abuse susceptibility.…
Abstract)
…The hypotheses of (1) gene x environment interaction in the susceptibility to experiment with drugs and (2) hypothalamus-pituitary-adrenal (HPA) axis involvement in mediating the effects of early adverse experiences and gene variants affecting serotonin function on substance abuse vulnerability were tested by investigating in 187 healthy adolescents the possible relevance of 5-HTT "S" polymorphism, childhood parental neglect reported retrospectively and HPA axis function to the susceptibility to experiment with illicit drugs.…
The hypotheses of (1) gene x environment interaction in the susceptibility to experiment with drugs and (2) hypothalamus-pituitary-adrenal (HPA) axis involvement in mediating the effects of early adverse experiences and gene variants affecting serotonin function on substance abuse vulnerability were tested by investigating in 187 healthy adolescents the possible relevance of 5-HTT "S" polymorphism, childhood parental neglect reported retrospectively and HPA axis function to the susceptibility to experiment with illicit drugs. Higher frequency of the 5-HTT SS genotype seems to be associated with an increased susceptibility to use illegal psychotropic drugs among the adolescents. At the same time, reduced maternal care perception was found to represent a key intermediate factor of the association between SS polymorphism and drug use, suggesting that genetic factors and parental behavior concur to drug use susceptibility. Our results also confirm the relationship between basal plasma levels of cortisol and adrenocorticotropic hormone (ACTH) on the one hand, and retrospective measures of neglect during childhood: the higher the mother and father neglect CECA-Q scores, the higher the plasma levels of the two HPA hormones. Such positive relationship has been proved to be particularly effective and important when associated to the S-allele, both in homozygote and heterozygote individuals. However, when tested together with genotype and parental neglect, the effect of HPA hormones such as cortisol and ACTH was not found to improve significantly the explanatory power of the risk model.
Also flagged:tumourlocalizationprostate cancerCancerprostate-specific antigenprostate cancers
Journal Article2010-04-01No SnippetsAkin O, Riedl CC, Ishill NM, Moskowitz CS, Zhang J, Hricak H.
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<h4>Objective</h4>To assess the effect of interactive dedicated training on radiology fellows' accuracy in assessing prostate cancer on MRI.<h4>Methods</h4>Eleven radiology fellows, blinded to clinical and pathological data, independently interpreted preoperative prostate MRI studies, scoring the likelihood of tumour in the peripheral and transition zones and extracapsular extension. Each fellow interpreted 15 studies before dedicated training (to supply baseline interpretation accuracy) and 200 studies (10/week) after attending didactic lectures. Expert radiologists led weekly interactive tutorials comparing fellows' interpretations to pathological tumour maps. To assess interpretation accuracy, receiver operating characteristic (ROC) analysis was conducted, using pathological findings as the reference standard.<h4>Results</h4>In identifying peripheral zone tumour, fellows' average area under the ROC curve (AUC) increased from 0.52 to 0.66 (after didactic lectures; p<0.0001) and remained at 0.66 (end of training; p<0.0001); in the transition zone, their average AUC increased from 0.49 to 0.64 (after didactic lectures; p=0.01) and to 0.68 (end of training; p=0.001). In detecting extracapsular extension, their average AUC increased from 0.50 to 0.67 (after didactic lectures; p=0.003) and to 0.81 (end of training; p<0.0001).<h4>Conclusion</h4>Interactive dedicated training significantly improved accuracy in tumour localization and especially in detecting extracapsular extension on prostate MRI.
Also flagged:pancreatic ductal adenocarcinomaPDACintraductal papillary mucinous carcinomasonic hedgehogShhKRAS
Journal Article2010-04-01✓ 1 SnippetFritz S, Fernández-del Castillo C, Iafrate AJ, Mino-Kenudson M, Neyhard N, LaFemina J, Stirman A, Warshaw AL, Thayer SP.
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<h4>Objectives</h4>Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas are a unique entity with malignant potential. Histologically, pancreatic ductal adenocarcinoma (PDAC) arising in IPMN (intraductal papillary mucinous carcinoma [IPMC]) appears similar to sporadic PDAC; biologically, however, IPMC seems to have a less aggressive clinical course. Little is known about the genetic signature of IPMC. In this study, we describe a novel xenograft model and cell culture created to biologically and genetically characterize these tumors.<h4>Methods</h4>Xenograft mice and cell lines were created from IPMC. Global genomic changes were evaluated by cytogenetic analysis and array comparative genomic hybridization. Specific mutations and sonic hedgehog (Shh) pathway activity were examined and xenografts evaluated for sensitivity to anti-Shh therapy.<h4>Results</h4>Cytogenetic analysis showed a tetraploid karyotype with multiple aberrations. KRAS and p53 mutations and overexpression of the Shh pathway were identified. Array comparative genomic hybridization revealed multiple chromosomal aberrations comparable with previously published data in IPMNs. Murine xenograft tumors were sensitive to anti-Shh treatment.<h4>Conclusions</h4>Characterization of IPMC cell lines and xenografts reveals similarities to previously published data on IPMN. In comparison to PDAC, moreover, these data reveal shared aberrations and distinct genomic changes. Thus, these xenograft model and cell lines may be useful for future preclinical investigations.
<h4>Objectives</h4>A functional polymorphism in the promoter region of the 5-hydroxytryptamine (serotonin) transporter (5-HTT) gene, termed 5-HTTLPR, alters transcription of the 5-HTT gene. The short variation (S allele) produces less transcriptional efficiency of serotonin, which can partly account for psychiatric disorders. Despite strong biological plausibility, the relationship between 5-HTTLPR and the risk of major depressive disorder (MDD) is unclear. To elucidate the relationship, we applied meta-analysis techniques to molecular studies of 5-HTTLPR and MDD.<h4>Methods</h4>A total of 22 articles were identified from MEDLINE through March 2008, using the search keywords 'depression,' '5-HTTLPR', and 'polymorphism.' The authors assessed the evidence of genotypic association using STATA Version 8.2.<h4>Results</h4>Summary frequencies of the S allele of 5-HTTLPR among Caucasians and Asians based on the random effects model were 42.1% [95% confidence interval (CI) = 40.5-43.6] and 76.8% (95% CI = 73.9-79.7), respectively. The distribution of the S allele was significantly different between Asians and Caucasians (P<0.001). The SS genotype was significantly associated with an increased risk of MDD among Caucasian populations (odds ratio = 1.41, 95% CI = 1.15-1.72), although there was no significant association among Asians.<h4>Conclusion</h4>Although the summary risk for developing MDD in individuals with the 'at-risk' SS genotype of 5-HTTLPR may be small, MDD is such a common disease that even a small increase in risk translates to a large number of excess MDD cases in the population. Thus, 5-HTT may be a candidate MDD susceptibility gene.
Also flagged:SLC9A9attention-deficit/hyperactivity disorderDOCK3ADHDbehavioral
Journal Article2010-04-01✓ 1 SnippetMarkunas CA, Quinn KS, Collins AL, Garrett ME, Lachiewicz AM, Sommer JL, Morrissey-Kane E, Kollins SH, Anastopoulos AD, Ashley-Koch AE.
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<h4>Objective</h4>A family was previously identified that cosegregates a pericentric inversion, inv(3)(p14 : q21), with an early-onset developmental condition, characterized by impulsive behavior and intellectual deficit. The inversion breakpoints lie within DOCK3 and SLC9A9 at the p-arm and q-arm, respectively. Based on this report, these genes were selected to be evaluated in a family-based attention-deficit/hyperactivity disorder (AD/HD) association study.<h4>Methods</h4>Conners' Parent (CPRS) and Teacher (CTRS) Rating Scales of AD/HD symptoms and Conners' Continuous Performance Test (CPT) measures were collected and a minimal number of tagging single-nucleotide polymorphisms (SNPs) in each gene were selected for analysis. Analyses were performed on families who met research criteria for AD/HD. Using the program, QTDT, each tagging SNP was tested for association with T-scores from the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) subscales according to the CTRS and CPRS, and five CPT measures.<h4>Results</h4>After adjusting for multiple testing, a SNP in the 3' UTR of SLC9A9, rs1046706, remained significantly associated (false discovery rate, q value <0.05) with scores on the DSM-IV hyperactive-impulsive and total symptom subscales according to the CTRS and errors of commission on the CPT. In addition, an intronic SLC9A9 SNP, rs2360867, remained significantly associated with errors of commission.<h4>Conclusion</h4>Our results suggest that SLC9A9 may be related to hyperactive-impulsive symptoms in AD/HD and the disruption of SLC9A9 may be responsible for the behavioral phenotype observed in the inversion family. The association with SLC9A9 is particularly interesting as it was recently implicated in a genome-wide association study for AD/HD. Further investigation of the role of SLC9A9 in AD/HD and other behavioral disorders is warranted.
<h4>Unlabelled</h4>The predictors for developing varices in patients with primary sclerosing cholangitis (PSC) have not been well studied prospectively. We sought to define the predictors for the presence of varices at baseline and for newly developing varices in patients with PSC. We used prospectively collected data from a multicenter randomized trial of high dose ursodeoxycholic acid for PSC. All 150 patients enrolled were reviewed for predictors of varices and we excluded 26 patients who had esophageal varices at baseline so that predictors of newly developing varices could be determined. Clinical examination, blood tests, and upper endoscopy were done before randomization, at 2 years and after 5 years. Liver biopsy was performed at entry and at 5 years. The median age (interquartile range) of patients was 45.9 years (35.8, 54.9). In a multivariable logistic regression, a higher Mayo risk score (> or =0.87) or a higher aspartate/alanine aminotransferase (AST/ALT) ratio (> or =1.12) were significantly associated with the presence of varices at initial endoscopy (odds ratio = 1.9 and 3.9). By the end of the study, 25 patients had new varices (20.2%). In a Cox model, after adjustment for baseline variables lower platelet count and higher total bilirubin at 2 years were significantly associated with the presence of new varices. The platelet count of 205 (x 10(9)/L) and the total bilirubin level of 1.7 mg/dL were the best cutoff values for the detection of new varices.<h4>Conclusion</h4>A higher Mayo risk score and higher AST/ALT ratio were significantly associated with the presence of varices at initial endoscopy. Lower platelet count and higher total bilirubin at 2 years were significantly associated with an increased risk of developing new varices in patients with PSC.
Also flagged:lung cancerPTPRDtumorcancersCDKN2Ap16
Journal Article2010-04-01✓ 1 SnippetKohno T, Otsuka A, Girard L, Sato M, Iwakawa R, Ogiwara H, Sanchez-Cespedes M, Minna JD, Yokota J.
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A total of 176 genes homozygously deleted in human lung cancer were identified by DNA array-based whole genome scanning of 52 lung cancer cell lines and subsequent genomic PCR in 74 cell lines, including the 52 cell lines scanned. One or more exons of these genes were homozygously deleted in one (1%) to 20 (27%) cell lines. These genes included known tumor suppressor genes, e.g., CDKN2A/p16, RB1, and SMAD4, and candidate tumor suppressor genes whose hemizygous or homozygous deletions were reported in several types of human cancers, such as FHIT, KEAP1, and LRP1B/LRP-DIP. CDKN2A/p16 and p14ARF located in 9p21 were most frequently deleted (20/74, 27%). The PTPRD gene was most frequently deleted (8/74, 11%) among genes mapping to regions other than 9p21. Somatic mutations, including a nonsense mutation, of the PTPRD gene were detected in 8/74 (11%) of cell lines and 4/95 (4%) of surgical specimens of lung cancer. Reduced PTPRD expression was observed in the majority (>80%) of cell lines and surgical specimens of lung cancer. Therefore, PTPRD is a candidate tumor suppressor gene in lung cancer. Microarray-based expression profiling of 19 lung cancer cell lines also indicated that some of the 176 genes, such as KANK and ADAMTS1, are preferentially inactivated by epigenetic alterations. Genetic/epigenetic as well as functional studies of these 176 genes will increase our understanding of molecular mechanisms behind lung carcinogenesis.
…>Materials and methods</h4>Thehemochromatosisscreening study in…
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<h4>Objective</h4>Hereditary hemochromatosis (HH) is a genetic condition characterized by increased iron absorption. Most HH cases are homozygous for the C282Y mutation in the HFE gene, but accurate prevalence data for the Norwegian population is lacking. In population studies, serum transferrin saturation (TS) is commonly used as a screening test. However, the sensitivity and specificity of TS in this setting is not well documented. The purpose of this study was to determine the prevalence of the C282Y mutation in the general population, and to evaluate the diagnostic accuracy of the TS test as a screening criterion for finding C282Y homozygotes.<h4>Materials and methods</h4>The hemochromatosis screening study in Nord-Trøndelag county, Norway (the HUNT2 study) comprised 65,238 participants. The HUNT biobank contains biological material and data from the participants, and 5000 individuals were randomly selected. Genotyping of the common HFE gene mutations was successful for 4827 samples, from which TS data existed for 4804 individuals. From these data we calculated the population frequency of the C282Y mutation, and the sensitivity and specificity of TS measurements.<h4>Results</h4>The prevalence of C282Y homozygosity in the population was 0.75%. Using 55% (men) and 50% (women) as decision limits, the sensitivity of two consecutive elevated TS measurements was 90.0% for men and 55.0% for women, whereas the specificity was 99.6% and 99.4%, respectively.<h4>Conclusion</h4>An unbiased estimate of the C282Y homozygote prevalence in Norway is 0.75%. Two measurements of TS is an accurate screening test for C282Y homozygosity in men, but not in women.
Also flagged:colorectal cancercancercancersbreast cancerprostate cancerssolid cancers
Journal Article2010-04-01✓ 5 SnippetsOsborne NJ, Gurrin LC, Allen KJ, Constantine CC, Delatycki MB, McLaren CE, Gertig DM, Anderson GJ, Southey MC, Olynyk JK, Powell LW, Hopper JL, Giles GG, English DR.
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…HFE C282Y homozygotes have twice the risk of colorectal and breast cancer compared with those individuals without the C282Y variant.…
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…HFE C282Y homozygotes are at increased risk of breast and colorectal cancer.…
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…The evidence that mutations in the HFE gene for hemochromatosis are associated with increased cancer risk is inconsistent.…
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…<h4>Unlabelled</h4>The evidence that mutations in the HFE gene for hemochromatosis are associated with increased cancer risk is inconsistent.…
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<h4>Unlabelled</h4>The evidence that mutations in the HFE gene for hemochromatosis are associated with increased cancer risk is inconsistent. The Melbourne Collaborative Cohort Study is a prospective cohort study that commenced recruitment in 1990. Participants born in Australia, New Zealand, the United Kingdom, or Ireland (n = 28,509) were genotyped for the HFE C282Y (substitution of tyrosine for cysteine at amino acid 282) variant. Incident cancers were ascertained from Australian cancer registries during an average of 14 years follow-up. Hazard ratios (HRs), confidence intervals (CIs), and P values were obtained from separate Cox regression analyses for colorectal, breast, and prostate cancers, all other solid cancers, and all cancers. Compared to those with no C282Y variant, C282Y homozygotes were at increased risk of colorectal cancer (HR = 2.28; 95% CI = 1.22, 4.25; P = 0.01) and female C282Y homozygotes were at increased risk of developing breast cancer (HR = 2.39; 95% CI = 1.24, 4.61; P = 0.01), but male C282Y homozygotes were not at increased risk for prostate cancer (HR = 0.96; 95% CI = 0.43, 2.15; P = 0.92). C282Y/H63D compound heterozygotes were not at increased risk for colorectal cancer (HR = 1.27; 95% CI = 0.80, 2.01), breast cancer (HR = 1.16; 95% CI = 0.74, 1.84), or prostate cancer (HR = 1.08; 95% CI = 0.68, 1.70).<h4>Conclusion</h4>HFE C282Y homozygotes have twice the risk of colorectal and breast cancer compared with those individuals without the C282Y variant.
…Mutations of the UROD and hemochromatosis (HFE) genes are genetic factors in some PCT patients which can be mimicked in mice heterozygous for the Hfe and Urod null genes.…
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…the UROD andhemochromatosis(HFE) genes are…
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…UROD and hemochromatosis (HFE) genes are genetic…
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…heterozygous for theHfeand Urod null…
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Many toxicological disorders, in common with numerous human diseases, are probably the consequence of multigene interactions with a variety of chemical and physiological factors. The importance of genetic factors may not be obvious initially from association studies because of their complexity and variable penetrance. The human disease, porphyria cutanea tarda (PCT), is a skin disease caused by the photosensitizing action of porphyrins arising secondary to the decreased activity of an enzyme of heme biosynthesis, uroporphyrinogen decarboxylase (UROD), in the liver. It is triggered by idiosyncratic hepatic interaction between genetic factors and chemicals such as alcohol, estrogenic drugs, and polyhalogenated aromatics. PCT and its animal models are known collectively as the hepatic uroporphyrias. There is strong evidence for the participation of iron in the pathogenesis of these conditions. Mouse models have been used to explore the relative importance of a variety of agents such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), alcohol, and iron in the development of uroporphyria and to elucidate the mechanism of the depression of hepatic UROD activity. Mutations of the UROD and hemochromatosis (HFE) genes are genetic factors in some PCT patients which can be mimicked in mice heterozygous for the Hfe and Urod null genes. Association studies of uroporphyria induced by TCDD or hexachlorobenzene with DNA markers in mouse intercrosses have shown the participation of other, unknown, genetic factors in addition to the strong influence of the Ahr gene. The pathogenesis of hepatic uroporphyrias exemplifies the complexity of the interactions between chemical and genetic factors that can contribute to the hepatotoxicity of chemicals.
Also flagged:embryonal carcinomateratocarcinomasheat shock 27 kDa protein-1TGF beta receptorbeta-galactoside-binding lectinLGALS1
Journal Article2010-04-01✓ 1 SnippetChaerkady R, Kerr CL, Kandasamy K, Marimuthu A, Gearhart JD, Pandey A.
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Pluripotent human embryonic stem cells (ESCs) can be differentiated in vitro into a variety of cells which hold promise for transplantation therapy. Human embryonal carcinoma cells (ECCs), stem cells of human teratocarcinomas, are considered a close but malignant counterpart to human ESCs. In this study, a comprehensive quantitative proteomic analysis of ESCs and ECCs was carried out using the iTRAQ method. Using two-dimensional LC and MS/MS analyses, we identified and quantitated approximately 1800 proteins. Among these are proteins associated with pluripotency and development as well as tight junction signaling and TGFbeta receptor pathway. Nearly approximately 200 proteins exhibit more than twofold difference in abundance between ESCs and ECCs. Examples of early developmental markers high in ESCs include beta-galactoside-binding lectin, undifferentiated embryonic cell transcription factor-1, DNA cytosine methyltransferase 3beta isoform-B, melanoma antigen family-A4, and interferon-induced transmembrane protein-1. In contrast, CD99-antigen (CD99), growth differentiation factor-3, cellular retinoic acid binding protein-2, and developmental pluripotency associated-4 were among the highly expressed proteins in ECCs. Several proteins that were highly expressed in ECCs such as heat shock 27 kDa protein-1, mitogen-activated protein kinase kinase-1, nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor like-2, and S100 calcium-binding protein-A4 have also been attributed to malignancy in other systems. Importantly, immunocytochemistry was used to validate the proteomic analyses for a subset of the proteins. In summary, this is the first large-scale quantitative proteomic study of human ESCs and ECCs, which provides critical information about the regulators of these two closely related, but developmentally distinct, stem cells.
Also flagged:Baxcell adhesion moleculesaxonalDopamine receptorsdopamineexocytosis
Journal Article2010-04-01✓ 1 SnippetKeeley PW, Reese BE.
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To determine the role of homotypic interactions between neighboring dopaminergic amacrine (DA) cells upon dendritic morphogenesis, the morphology of single cells was examined relative to the positioning of all neighboring homotypic cells. For each labeled cell, the dendritic field was reconstructed, its Voronoi domain was calculated, and the two were related. The dendritic fields of DA cells were observed to be large, sparse, and highly irregular. Dendrites readily overlapped those of neighboring cells, showing no evidence for dendritic tiling or inter-digitation consistent with homotypic repulsion or avoidance. Furthermore, a direct comparison of dendritic field area with the Voronoi domain area of the same cell showed no evidence for dendritic growth being constrained or biased by the local distribution of homotypic neighbors in wild-type retinas. A comparison of the processes of adjacent filled cells confirmed their immediate proximity to one another within the inner plexiform layer, indicating that they do not engage in mutual avoidance by coursing at different depths. Together, these results suggest that the morphogenesis of DA cells is independent of homotypic interactions. However, in the absence of the pro-apoptotic Bax gene, which yields a fourfold increase in DA cell number, a small but significant reduction in dendritic field size was obtained, although not so great as would be predicted by the increase in density. The present results are considered in light of recent studies on the role of cell adhesion molecules expressed by developing DA cells.
Also flagged:lipidobesitydyslipidemiaheart diseasecardiovascular diseaseamino acid
Journal Article2010-04-01No SnippetsParnell LD, Lee YC, Lai CQ.
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<h4>Purpose of review</h4>Obesity, dyslipidemia and cardiovascular disease are complex and determined by both genetic and environmental factors and their inter-relationships. Many associations from genome-wide association studies and candidate gene approaches have described a multitude of polymorphisms associating with lipid and obesity phenotypes but identified genetic variants account for only a small fraction of phenotypic variation.<h4>Recent findings</h4>That many genotype-phenotype associations involve variants under positive selection and that those variants respond to environmental cues together suggest prominent roles for both genetic adaptation and their interactions with the environment. Adaptive genetic variations interacting with environment modulate disease susceptibility but the level to which those variants contribute to dyslipidemia and obesity and how environmental factors, especially diet, alter the genetic association is not yet completely known.<h4>Summary</h4>It is evident that genetic variants under positive selection make important contributions to obesity and heart disease risk. Advances in resequencing the entire human genome will enable accurate identification of adaptive variants. Considering interactions between environmental factors and genotypes will empower both genome-wide association studies and characterization of the relationship between positive selection and the obese and dyslipidemic conditions.
Also flagged:neurological diseasespolyglutamine diseasestranslational modificationpathogenesisautophagydegradation
Journal Article2010-04-01No SnippetsLa Spada AR, Taylor JP.
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Repeat expansion mutations cause at least 22 inherited neurological diseases. The complexity of repeat disease genetics and pathobiology has revealed unexpected shared themes and mechanistic pathways among the diseases, such as RNA toxicity. Also, investigation of the polyglutamine diseases has identified post-translational modification as a key step in the pathogenic cascade and has shown that the autophagy pathway has an important role in the degradation of misfolded proteins--two themes that are likely to be relevant to the entire neurodegeneration field. Insights from repeat disease research are catalysing new lines of study that should not only elucidate molecular mechanisms of disease but also highlight opportunities for therapeutic intervention for these currently untreatable disorders.
During development, neural networks are established in a highly organized manner, which persists throughout life. Neurotrophins play crucial roles in the developing nervous system. Among the neurotrophins, brain-derived neurotrophic factor (BDNF) is highly conserved in gene structure and function during vertebrate evolution, and serves an important role during brain development and in synaptic plasticity. BDNF participates in the formation of appropriate synaptic connections in the brain, and disruptions in this process contribute to disorders of cognitive function. In this review, we first briefly highlight current knowledge on the expression, regulation, and secretion of BDNF. Further, we provide an overview of the possible actions of BDNF in the development of neural circuits, with an emphasis on presynaptic actions of BDNF during the structural development of central neurons.
Also flagged:Synthesiscarbonylvesicular acetylcholine transporterVAChTphenylpiperidyl
Journal Article2010-04-01No SnippetsEfange SM, Khare AB, von Hohenberg K, Mach RH, Parsons SM, Tu Z.
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To identify selective high-affinity inhibitors of the vesicular acetylcholine transporter (VAChT), we have interposed a carbonyl group between the phenyl and piperidyl groups of the prototypical VAChT ligand vesamicol and its more potent analogues benzovesamicol and 5-aminobenzovesamicol. Of 33 compounds synthesized and tested, 6 display very high affinity for VAChT (K(i), 0.25-0.66 nM) and greater than 500-fold selectivity for VAChT over sigma(1) and sigma(2) receptors. Twelve compounds have high affinity (K(i), 1.0-10 nM) and good selectivity for VAChT. Furthermore, 3 halogenated compounds, namely, trans-3-[4-(4-fluorobenzoyl)piperidinyl]-2-hydroxy-1,2,3,4-tetrahydronaphthalene (28b) (K(i) = 2.7 nM, VAChT/sigma selectivity index = 70), trans-3-[4-(5-iodothienylcarbonyl)piperidinyl]-2-hydroxy-1,2,3,4-tetrahydronaphthalene (28h) (K(i) = 0.66 nM, VAChT/sigma selectivity index = 294), and 5-amino-3-[4-(p-fluorobenzoyl)piperidinyl]-2-hydroxy-1,2,3,4,-tetrahydronaphthalene (30b) (K(i) = 2.40 nM, VAChT/sigma selectivity index = 410) display moderate to high selectivity for VAChT. These three compounds can be synthesized with the corresponding radioisotopes so as to serve as PET/SPECT probes for imaging the VAChT in vivo.
This study assesses the capability of high-resolution surface analytical tools to distinguish immobilized antibody orientations on patterned surfaces designed for antibody affinity capture. High-fidelity, side-by-side copatterning of protein A (antibody Fc domain affinity reagent) and fluorescein (antibody Fab domain hapten) was achieved photolithographically on commercial amine-reactive hydrogel polymer surfaces. This was verified from fluorescence imaging using fluorescently labeled protein A and intrinsic fluorescence from fluorescein. Subsequently, dye-labeled murine antifluorescein antibody (4-4-20) and antibody Fab and Fc fragments were immobilized from solution onto respective protein A- and fluorescein- copatterned or control surfaces using antibody-ligand affinity interactions. Fluorescence assays support specific immobilization to fluorescein hapten- and protein A-patterned regions through antigen-antibody recognition and natural protein A-Fc domain interactions, respectively. Affinity-based antibody immobilization on the two different copatterned surfaces generated side-by-side full antibody "heads-up" and "tails-up" oriented surface patterns. Time-of-flight secondary ion mass spectrometry (TOF-SIMS) analysis, sensitive to chemical information from the top 2 to 3 nm of the surface, provided ion-specific images of these antibody patterned regions, imaging and distinguishing characteristic ions from amino acids enriched in Fab domains for antibodies oriented in "heads-up" regions, and ions from amino acids enriched in Fc domains for antibodies oriented in "tails-up" regions. Principal component analysis (PCA) improved the distinct TOF-SIMS amino acid compositional and ion-specific surface mapping sensitivity for each "heads-up" versus "tails-up" patterned region. Characteristic Fab and Fc fragment immobilized patterns served as controls. This provides first demonstration of pattern-specific, antibody orientation-dependent surface maps based on antibody domain- and structure-specific compositional differences by TOF-SIMS analysis. Since antibody immobilization and orientation are critical to many technologies, orientation characterization using TOF-SIMS could be very useful and convenient for immobilization quality control and understanding methods for improving the performance of antibody-based surface capture assays.
Also flagged:carbohydrateglycanheparinschondroitinsulfate proteoglycansN
Journal Article2010-04-01✓ 1 SnippetBowman MJ, Zaia J.
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This study illustrates the utility of tetraplex stable isotope coded tags in mass spectrometric glycomics using three carbohydrate classes. The teteraplex tags allow for the direct comparison of glycan compositions within four samples using capillary scale hydrophilic interaction chromatography with online mass spectrometry. In addition, the ability to discern glycan structural isomers is shown based on the tandem mass spectra of each composition using nanospray ionization. Results are shown for chondroitin sulfate proteoglycans, low molecular weight heparins, full length heparins, and N-glycans from alpha-1-acid glycoproteins from four mammalian species. The data demonstrate the value of the tetraplex stable isotope tagging approach for producing high-quality glycomics compositional profiling and fine structural analysis.
Also flagged:synthesisiron oxideaminetumorchlorotoxinpeptide
Journal Article2010-04-01No SnippetsSun C, Du K, Fang C, Bhattarai N, Veiseh O, Kievit F, Stephen Z, Lee D, Ellenbogen RG, Ratner B, Zhang M.
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Multifunctional superparamagnetic nanoparticles have been developed for a wide range of applications in nanomedicine, such as serving as tumor-targeted drug carriers and molecular imaging agents. To function in vivo, the development of these novel materials must overcome several challenging requirements including biocompatibility, stability in physiological solutions, nontoxicity, and the ability to traverse biological barriers. Here we report a PEG-mediated synthesis process to produce well-dispersed, ultrafine, and highly stable iron oxide nanoparticles for in vivo applications. Utilizing a biocompatible PEG coating bearing amine functional groups, the produced nanoparticles serve as an effective platform with the ability to incorporate a variety of targeting, therapeutic, or imaging ligands. In this study, we demonstrated tumor-specific accumulation of these nanoparticles through both magnetic resonance and optical imaging after conjugation with chlorotoxin, a peptide with high affinity toward tumors of the neuroectodermal origin, and Cy5.5, a near-infrared fluorescent dye. Furthermore, we performed preliminary biodistribution and toxicity assessments of these nanoparticles in wild-type mice through histological analysis of clearance organs and hematology assay, and the results demonstrated the relative biocompatibility of these nanoparticles.
Also flagged:Huntington's diseaseHDglutaminedementiaSynaptic transmissionneurotransmitter
Journal Article2010-04-01✓ 2 SnippetsRozas JL, Gómez-Sánchez L, Tomás-Zapico C, Lucas JJ, Fernández-Chacón R.
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…HD (Huntington's disease) is produced by the expression of mutant forms of the protein htt (huntingtin) containing a pathologically expanded poly-glutamine repeat.…
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…of the proteinhtt(huntingtin) containing a…
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HD (Huntington's disease) is produced by the expression of mutant forms of the protein htt (huntingtin) containing a pathologically expanded poly-glutamine repeat. For unknown reasons, in HD patients and HD mouse models, neurons from the striatum and cerebral cortex degenerate and lead to motor dysfunction and dementia. Synaptic transmission in those neurons becomes progressively altered during the course of the disease. However, the relationship between synaptic dysfunction and neurodegeneration in HD is not yet clear. Are there early specific functional synaptic changes preceding symptoms and neurodegeneration? What is the role of those changes in neuronal damage? Recent experiments in a Drosophila model of HD have showed that abnormally increased neurotransmitter release might be a leading cause of neurodegeneration. In the present review, we summarize recently described synaptic alterations in HD animal models and discuss potential underlying molecular mechanisms.
…HD (Huntington's disease) is caused by a polyQ (polyglutamine) expansion in the huntingtin protein, which leads to protein misfolding and aggregation of this protein.…
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HD (Huntington's disease) is caused by a polyQ (polyglutamine) expansion in the huntingtin protein, which leads to protein misfolding and aggregation of this protein. Abnormal copper accumulation in the HD brain was first reported more than 15 years ago. Recent findings show that copper-regulatory genes are induced during HD and copper binds to an N-terminal fragment of huntingtin, supporting the involvement of abnormal copper metabolism in HD. We have demonstrated that in vitro copper accelerates the fibrillization of an N-terminal fragment of huntingtin with an expanded polyQ stretch (httExon1). As we found that copper also increases polyQ aggregation and toxicity in mammalian cells expressing httExon1, we investigated further whether overexpression of genes involved in copper metabolism, notably MTs (metallothioneins) known to bind copper, protect against httExon1 toxicity. Using a yeast model of HD, we have shown that overexpression of several genes involved in copper metabolism reduces polyQ-mediated toxicity. Overexpression of MT-3 in mammalian cells significantly reduced polyQ aggregation and toxicity. We propose that copper-binding and/or -chaperoning proteins, especially MTs, are potential therapeutic targets for HD.
Also flagged:histone acetyltransferase MOFhistonelysinechromatinMOFhistone H4
Journal Article2010-04-01No SnippetsLi X, Dou Y.
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In higher eukaryotes, histone acetyltransferase MOF (male absent on the first) is the major enzyme that acetylates histone H4 lysine 16, a prevalent mark associated with chromatin decondensation. Recent studies show that MOF resides in two different but evolutionarily conserved complexes, MSL and MOF-MSL1v1. Although these two MOF complexes have indistinguishable activity on histone H4 K16, they differ dramatically in acetylating non-histone substrate p53. The regulation of MOF activity in these complexes remains elusive. Given the evolution conservation of MOF and the importance of H4 K16 acetylation in maintaining higher order chromatin structures, understanding the function and regulation of MOF bears great significance. Here, we discussed the key differences in two MOF complexes that may shed light on the regulation of their distinct acetyltransferase activities. We also discussed coordinated functions of two MOF complexes with different histone methyltransferase complexes in transcription regulation.
Also flagged:Netrin-1tumornetrin-1 dependence receptorsnetrin-1 receptorsin Colorectal Cancerdependence receptors
Journal Article2010-04-01✓ 2 SnippetsParadisi A, Mehlen P.
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…The netrin-1 receptors, DCC (for Deleted in Colorectal Cancer) and UNC5H (UNC5 homologues), indeed belong to the functional family of dependence receptors that share the ability to induce apoptosis in the absence of their ligands and such a trait has been hypothesized to confer these receptors a tumor suppressor activity as their presence render cell survival dependent on ligand availability.…
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…The netrin-1 receptors,DCC(for Deleted in…
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Netrin-1 discovered as a neuronal navigation cue, has been recently proposed to play a crucial role during colorectal tumorigenesis by regulating apoptosis. This survival activity is mediated via the inhibition of the so-called netrin-1 dependence receptors. The netrin-1 receptors, DCC (for Deleted in Colorectal Cancer) and UNC5H (UNC5 homologues), indeed belong to the functional family of dependence receptors that share the ability to induce apoptosis in the absence of their ligands and such a trait has been hypothesized to confer these receptors a tumor suppressor activity as their presence render cell survival dependent on ligand availability. As a consequence, human tumors show either a loss of dependence receptors or a gain of netrin-1, allowing tumors to escape this safeguard mechanism. We recently found that netrin-1 is a direct transcriptional target of the transcription factor NFκB, and that a fraction of colorectal tumors show a netrin-1 gain parallel to NFκB activation. Moreover, colorectal cancers from patients affected by inflammatory bowel diseases (IBD) show upregulation of netrin-1. Several evidences suggest a tight link between chronic inflammation and tumorigenesis, mainly through NFκB activation. We propose that induction of netrin-1 expression via NFκB in IBD patients could affect colorectal tumor promotion and progression and that inhibition of netrin-1 could be an innovative target for drug therapy in inflammation-driven colorectal cancers.
Also flagged:Synapsedepression5-HT receptorsNMDA receptorserotoninSerotonin receptors
Journal Article2010-04-01✓ 2 SnippetsBennett MR.
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Abstract)
…of 5-HT transporter (5-HTT) efficacy, either during…
Abstract)
…in animals through5-HTTtransgenic knockouts, is…
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Depression is accompanied by an increase in activity in the amygdala and a decrease in the rostral anterior cingulate cortex (rACC), with the former attributed to a failure of the latter to exert its normal inhibitory influence. This failure is likely due to regression of synaptic connections between the rACC and the amygdala, a process reversed in part by selective serotonin reuptake inhibitors (SSRIs). The present work presents a hypothesis as to how SSRIs might bring about this process and hence normalization of activity, at least in patients that are responsive to SSRIs. Serotonin receptors of the excitatory 5-HT(2A)R class increase N-methyl-D-aspartate receptor (NMDAR) efficacy, while those of the inhibitory 5-HT(1A)R class decrease NMDAR efficacy. A decrease of 5-HT transporter (5-HTT) efficacy, either during human development through functional polymorphisms, or in animals through 5-HTT transgenic knockouts, is accompanied by a decrease in 5-HT(1A)R and hence an increase in excitability and NMDAR efficacy which drives an increase in synaptic spines in the amygdala. As the limbic region of the brain normally possesses high levels of 5-HT(1A)R the effect of loss of these is to increase excitation in this region, as is observed. Changes in the level of extracellular 5-HT in adult animals also modulates the density of synaptic spines, with these increasing with an increase in 5-HT, possibly as a consequence of increases in 5-HT(2A)R activity over that of 5-HT(1A)R. Increasing extracellular levels of 5-HT with SSRIs would then lead to an increase in excitability and in synaptic spines for afferents in the dorsal rostral anterior cingulate cortex but not in the ventral regions such as the amygdala that have few 5-HT(2A)R. This allows dorsal regions to once more exert their inhibitory influence over ventral regions. In this way, SSRIs may exert their effect in normalizing dorsal hypometabolism and ventral hypermetabolism in those suffering from depression.
Also flagged:post-translational modificationslocalizationamino acidSUMOylationphosphorylationmetabolism
Journal Article2010-04-01✓ 5 SnippetsWang Y, Lin F, Qin ZH.
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…The role of post-translational modifications of huntingtin in the pathogenesis of Huntington's disease.…
Abstract)
…Cleavage and clearance of mutant Htt, and the interactions between mutant Htt and other cellular proteins are important biochemical events leading to Huntington's disease.…
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…modifications of huntingtin (Htt) have been described.…
Post-translational modifications are rapid, effective and reversible ways to regulate protein stability, localization, function, and their interactions with other molecules. Post-translational modifications usually occur as chemical modifications at amino acid residues, including SUMOylation, phosphorylation, palmitoylation, acetylation, etc. These complex biochemical modifications tightly regulate and control a variety of cellular processes. Several forms of post-translational modifications of huntingtin (Htt) have been described. These modifications affect Htt metabolism, protein-protein interactions and cellular toxicity. Cleavage and clearance of mutant Htt, and the interactions between mutant Htt and other cellular proteins are important biochemical events leading to Huntington's disease. Therefore, identifying signaling pathways of Htt modification and evaluating the significance of Htt modifications would lead to a better understanding of the normal function of wild-type Htt and the pathogenic mechanisms of mutant Htt.
Also flagged:ExtracellularnucleotidesP2 receptorsnucleosidealkaline phosphataseglaucoma
Journal Article2010-04-01No SnippetsEliahu S, Martín-Gil A, Perez de Lara MJ, Pintor J, Camden J, Weisman GA, Lecka J, Sévigny J, Fischer B.
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Extracellular nucleotides can modify the production or drainage of the aqueous humor via activation of P2 receptors and therefore affect the intraocular pressure (IOP). We have synthesized slowly hydrolyzable nucleoside di- and triphosphate analogues, 1, and 8-14. Analogues 8-14 were completely resistant to hydrolysis by alkaline phosphatase over 30 min at 37 degrees C. In human blood serum, analogues 8-14 exhibited high stability, e.g., analogues 9 and 10-14 were only 15% and 0% degraded after 24 h, respectively. Moreover, analogues 8-14 were highly stable at pH 1.4 (t(1/2) 1 h-30 days). Analogues 8-14 were agonists of the P2Y(1) receptor (EC(50) 0.57-9.54 muM). Ocular administration of most analogues into rabbits reduced IOP, e.g., analogue 9 reduced IOP by 32% (EC(50) 95.5 nM). Analogue 9 was more effective at reducing IOP than several common glaucoma drugs and represents a promising alternative to timolol maleate, which cannot be used for the treatment of patients suffering from asthma or cardiac problems.
Also flagged:Autoimmune hepatitisliver diseasesteroidscirrhosisAcute hepatitistype
Journal Article2010-04-01✓ 1 SnippetFallatah HI, Akbar HO, Qari YA.
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…saturation for possiblehemochromatosiswere reviewed.…
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<h4>Background/aim</h4>Autoimmune hepatitis (AIH) is a common cause of end-stage liver disease worldwide. It is a disease prevalent in children and adults, with female predominance and variable clinical presentations. AIH has favorable responses to steroids and immunomodulators. Diagnosis of AIH is based on clinical and laboratory criteria, as suggested by the International Autoimmune Hepatitis Group. Data on the disease pattern of AIH from the Middle East countries is scarce.<h4>Materials and methods</h4>In this retrospective analysis, we studied clinical and laboratory features, immunological data, radiological findings, liver biopsy findings and response to therapy in patients with AIH from the hepatology clinics of King Abdul Aziz, University Hospital, Jeddah, from 1994 to 2008.<h4>Results</h4>We diagnosed 41 patients with AIH, and 33 were included in the analysis. The mean age was 32.3 years, with female predominance of 75.7%. De-compensated cirrhosis at presentation was found in 45.5% of the patients. Acute hepatitis was associated with significantly higher levels of the serum ALT and bilirubin (P=0.001 and P=0.03, respectively). All our patients had type 1 AIH. Treatment with prednisolone and azathioprine resulted in complete or partial remission in majority of the patients (54.8%). However, patients with advanced disease showed a poorer response to treatment (P=0.016). Six patients with poor compliance had relapse of AIH. Two patients had a flare of the disease during pregnancy, and they responded well with prednisolone. The longest follow-up was 14 years and the shortest was 2 months. Four patients died from liver disease.<h4>Conclusion</h4>AIH patients in Saudi Arabia are likely to present with advanced disease at a young age and would have a poorer response to therapy as compared with patients in other countries worldwide.
…genetic diagnosis ofhemochromatosisis also debated,…
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…hemochromatosis…
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Accurate evaluation of iron overload is necessary to establish the diagnosis of hemochromatosis and guide chelation treatment in transfusion-dependent anemia. The liver is the primary site for iron storage in patients with hemochromatosis or transfusion-dependent anemia, therefore, liver iron concentration (LIC) accurately reflects total body iron stores. In the past 20 years, magnetic resonance imaging (MRI) has emerged as a promising method for measuring LIC in a variety of diseases. We review the potential role of MRI in LIC determination in the most important disorders that are characterized by iron overload, that is, thalassemia major, other hemoglobinopathies, acquired anemia, and hemochromatosis. Most studies have been performed in thalassemia major and MRI is currently a widely accepted method for guiding chelation treatment in these patients. However, the lack of correlation between liver and cardiac iron stores suggests that both organs should be evaluated with MRI, since cardiac disease is the leading cause of death in this population. It is also unclear which MRI method is the most accurate since there are no large studies that have directly compared the different available techniques. The role of MRI in the era of genetic diagnosis of hemochromatosis is also debated, whereas data on the accuracy of the method in other hematological and liver diseases are rather limited. However, MRI is a fast, non-invasive and relatively accurate diagnostic tool for assessing LIC, and its use is expected to increase as the role of iron in the pathogenesis of liver disease becomes clearer.
Also flagged:Hepatic osteodystrophyosteoporosisDeoxypyridinolinealkaline phosphataseALPinsulin-like growth factor-1
Journal Article2010-04-01✓ 1 SnippetGoral V, Simsek M, Mete N.
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…hemochromatosis…
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<h4>Aim</h4>To investigate the correlation between hepatic osteodystrophy and osteoporosis in patients with liver cirrhosis.<h4>Methods</h4>Bone mineral density of the patients (n = 55) and that of the control group (n = 30) were measured by dual-energy X-ray absorptiometry. All the women in the study were premenopausal. Deoxypyridinoline, pyridinoline and urinary Ca(2+) were measured as bone destruction markers, while alkaline phosphatase (ALP), osteocalcin and insulin-like growth factor-1 (IGF-1) were measured as bone formation markers. Furthermore, interleukin-1 (IL-1), IL-6, tumor necrosis factor alpha (TNF-alpha), vitamin D3, direct bilirubin, albumin, cortisol and parathyroid hormone (PTH) levels were measured. The independent Student t test and chi(2) test were employed in comparing both groups, and the Pearson correlation test was used to determine associations.<h4>Results</h4>Comparing cirrhosis and control groups, lumbar total T-score (-1.6 + or - 1.2 g/cm(2) vs -0.25 + or - 1.3 g/cm(2), P < 0.001), lumbar total Z-score (-1.2 + or - 1.23 g/cm(2) vs -0.6 + or - 1.3 g/cm(2), P < 0.001), total femur T-score (-0.05 + or - 1 g/cm(2) vs -0.6 + or - 0.9 g/cm(2), P = 0.003) and total femur Z-score (-0.08 + or - 1.5 g/cm(2) vs 0.7 + or - 0.9 g/cm(2), P = 0.003) showed significantly lower values in the cirrhosis group. Blood ALP level (109.2 + or - 57 U/L vs 62.6 + or - 32.5 U/L, P < 0.001), IL-6 level (27.9 + or - 51.6 pg/mL vs 3.3 + or - 3.1 pg/mL, P = 0.01), TNF-alpha level (42.6 + or - 33.2 pg/mL vs 25.3 + or - 12.3 pg/mL, P = 0.007) and direct bilirubin level (0.9 + or - 0.7 mg/dL vs 0.3 + or - 0.2 mg/dL, P < 0.001) were significantly higher in the cirrhosis group. IGF-1 level (47.7 + or - 26.2 ng/mL vs 143.4 + or - 53.2 ng/mL, P < 0.001), osteocalcin level (1.05 + or - 2.5 ng/mL vs 7.0 + or - 13 ng/mL, P = 0.002) and 24 h urinary Ca(2+) (169.6 + or - 227.2 mg/dL vs 287 + or - 168.6 mg/dL, P = 0.003) were significantly lower in the cirrhosis group. Urinary deoxypyridinoline/creatinine (9.4 + or - 9.9 pmol/micromol vs 8.1 + or - 5.3 pmol/micromol, P = 0.51), urinary pyridinoline/creatinine (51.3 + or - 66.6 pmol/micromol vs 29 + or - 25.8 pmol/micromol, P = 0.08), blood IL-1 level (3.4 + or - 8.8 pg/mL vs 1.6 + or - 3.5 pg/mL, P = 0.29), vitamin D3 level (18.6 + or - 13.3 microg/L vs 18.4 + or - 8.9 microg/L, P = 0.95), cortisol level (11.1 + or - 4.8 microg/dL vs 12.6 + or - 4.3 microg/dL, P = 0.15) and PTH level (42.7 + or - 38 microg/dL vs 34.8 + or - 10.9 microg/dL, P = 0.27) were not significantly different.<h4>Conclusion</h4>Hepatic osteodystrophy is an important complication encountered in patients with liver cirrhosis and all patients should be monitored for hepatic osteodystrophy.
Also flagged:prostacyclin synthasecardiovascular diseaseProstacyclinplatelet aggregationvasoconstrictionPGI2 synthase
Journal Article2010-04-01✓ 5 SnippetsNakayama T.
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Abstract)
…These results suggest that PGI2 function depends on the different alleles of the PTGIS gene and that they may influence the risk of cardiovascular disease.…
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…PTGIS gene is localized to 20q13.11-13 and a candidate gene for cardiovascular disease…
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…PTGIS gene and that they may influence the risk of cardiovascular disease…
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…PGI2 synthase (PTGIS), a catalyst of…
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…ThePTGISgene is localized…
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Prostacyclin (PGI2) inhibits platelet aggregation and vasoconstriction. PGI2 synthase (PTGIS), a catalyst of PGI2 synthesis from prostaglandin H2, is widely distributed and predominantly found in vascular endothelial and smooth muscle cells. The PTGIS gene is localized to 20q13.11-13 and a candidate gene for cardiovascular disease. We discovered mutations and polymorphisms in this gene and reported that they were associated with essential hypertension, myocardial infarction, and cerebral infarction. These results suggest that PGI2 function depends on the different alleles of the PTGIS gene and that they may influence the risk of cardiovascular disease. Thus, individualized management strategies, such as the administration of PGI2 analogues, could be selected for variants of this gene, to help prevent the development of cardiovascular disease.
Also flagged:Neuropeptidespeptidehormonesneuropeptidepeptidesprohormones
Journal Article2010-04-01✓ 2 SnippetsXie F, London SE, Southey BR, Annangudi SP, Amare A, Rodriguez-Zas SL, Clayton DF, Sweedler JV.
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Results)
…binding protein 1 (PEBP1).…
Results)
…binding protein 1 (PEBP1) and, lastly, CPN2,…
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<h4>Background</h4>Among songbirds, the zebra finch (Taeniopygia guttata) is an excellent model system for investigating the neural mechanisms underlying complex behaviours such as vocal communication, learning and social interactions. Neuropeptides and peptide hormones are cell-to-cell signalling molecules known to mediate similar behaviours in other animals. However, in the zebra finch, this information is limited. With the newly-released zebra finch genome as a foundation, we combined bioinformatics, mass-spectrometry (MS)-enabled peptidomics and molecular techniques to identify the complete suite of neuropeptide prohormones and final peptide products and their distributions.<h4>Results</h4>Complementary bioinformatic resources were integrated to survey the zebra finch genome, identifying 70 putative prohormones. Ninety peptides derived from 24 predicted prohormones were characterized using several MS platforms; tandem MS confirmed a majority of the sequences. Most of the peptides described here were not known in the zebra finch or other avian species, although homologous prohormones exist in the chicken genome. Among the zebra finch peptides discovered were several unique vasoactive intestinal and adenylate cyclase activating polypeptide 1 peptides created by cleavage at sites previously unreported in mammalian prohormones. MS-based profiling of brain areas required for singing detected 13 peptides within one brain nucleus, HVC; in situ hybridization detected 13 of the 15 prohormone genes examined within at least one major song control nucleus. Expression mapping also identified prohormone messenger RNAs in areas associated with spatial learning and social behaviours. Based on the whole-genome analysis, 40 prohormone probes were found on a commonly used zebra finch brain microarray. Analysis of these newly annotated transcripts revealed that six prohormone probes showed altered expression after birds heard song playbacks in a paradigm of song recognition learning; we partially verify this result experimentally.<h4>Conclusions</h4>The zebra finch peptidome and prohormone complement is now characterized. Based on previous microarray results on zebra finch vocal learning and synaptic plasticity, a number of these prohormones show significant changes during learning. Interestingly, most mammalian prohormones have counterparts in the zebra finch, demonstrating that this songbird uses similar biochemical pathways for neurotransmission and hormonal regulation. These findings enhance investigation into neuropeptide-mediated mechanisms of brain function, learning and behaviour in this model.
The beneficial role of statins in primary and secondary prevention of coronary heart disease has resulted in their frequent use in clinical practice. However, safety concerns, especially regarding hepatotoxicity, have driven multiple trials, which have demonstrated the low incidence of statin-related hepatic adverse effects. The most commonly reported hepatic adverse effect is the phenomenon known as transaminitis, in which liver enzyme levels are elevated in the absence of proven hepatotoxicity. This class effect is usually asymptomatic, reversible, and dose-related. However, the increasing incidence of chronic liver diseases, including nonalcoholic fatty liver disease and hepatitis C, has created a new challenge when initiating statin treatment in patients with high cardiovascular risk. These diseases result in abnormally high liver biochemistry values, discouraging statin use by clinicians, fostering treatment discontinuation, and leaving a large number of at-risk patients untreated. A PubMed/MEDLINE search of the literature regarding statin safety (January 1, 1994-December 31, 2008) was performed, using the following search terms: statin safety, statin-related hepatotoxicity, and chronic liver disease and statin use, as well as the specific names of different statins and different liver diseases. Relevant clinical trials, review articles, panel discussions, and guideline recommendations were selected. This review supports the use of statin treatment in patients with high cardiovascular risk whose elevated aminotransferase levels have no clinical relevance or are attributable to known stable chronic liver conditions. For each patient, the decision should be based on an individual assessment of risks and benefits.
Also flagged:major depressive disordermajor depressionchromosomesHuntingtincocaine use disordersneurologic disease
Journal Article2010-04-01✓ 4 SnippetsPerlis RH, Smoller JW, Mysore J, Sun M, Gillis T, Purcell S, Rietschel M, Nöthen MM, Witt S, Maier W, Iosifescu DV, Sullivan P, Rush AJ, Fava M, Breiter H, Macdonald M, Gusella J.
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Abstract)
…This was a case-control genetic association study of HTT CAG allele size in two discovery cohorts of individuals with major depressive disorder and comparison subjects without major depression as well as a replication cohort of individuals with major depression and comparison subjects without major depression.…
Abstract)
…Presymptomatic individuals with the Huntingtin (HTT) CAG expansion mutation that causes Huntington's disease may have higher levels of depressive symptoms than healthy comparison populations.…
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…<h4>Objective</h4>Presymptomatic individuals with the Huntingtin (HTT) CAG expansion mutation that causes Huntington's disease may have higher levels of depressive symptoms than healthy comparison populations.…
Abstract)
…the Huntingtin (HTT) CAG expansion…
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<h4>Objective</h4>Presymptomatic individuals with the Huntingtin (HTT) CAG expansion mutation that causes Huntington's disease may have higher levels of depressive symptoms than healthy comparison populations. However, the prevalence of HTT CAG repeat expansions among individuals diagnosed with major depressive disorder has not been established.<h4>Method</h4>This was a case-control genetic association study of HTT CAG allele size in two discovery cohorts of individuals with major depressive disorder and comparison subjects without major depression as well as a replication cohort of individuals with major depression and comparison subjects without major depression.<h4>Results</h4>CAG repeat lengths of 36 or greater were observed in six of 3,054 chromosomes from individuals with major depression, compared with none of 4,155 chromosomes from comparison subjects. In a third cohort, one expanded allele was observed among 1,202 chromosomes in the major depression group, compared with none of 2,678 chromosomes in comparison subjects. No clear pattern of clinical features was shared among individuals with the expanded repeats.<h4>Conclusions</h4>In clinical populations of individuals diagnosed with major depression, approximately 3 in 1,000 carried expanded HTT CAG alleles.
A functional variant of the serotonin transporter gene (5-HTTLPR) has been associated with increased risk for major depression in the context of stress. In attempting to understand the mechanisms underlying this relation, we tested the hypothesis that 5-HTTLPR genotype affects the speed with which amygdala is recruited during emotional processing in young girls with no history of psychiatric disorder. We used functional magnetic resonance imaging to compare the rise time to peak amygdala activation in 5-HTTLPR short-allele carriers and long-allele homozygotes during enhancement of sad mood. Relative to long-allele homozygotes, participants with at least one copy of the 5-HTTLPR short allele showed both stronger and earlier activation in left amygdala as they increased a sad mood state. Individuals carrying the short allele appear to exhibit a neural 'readiness' to engage and enhance negative affect. Future research should examine how exposure to negative life events and more chronic sadness modify the time course of amygdala activity during the experience of negative emotion.
Also flagged:synapsenucleuscytoplasmtransport granulesRNA-binding proteinsprotein synthesis
Journal Article2010-04-01No SnippetsLoya CM, Van Vactor D, Fulga TA.
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Post-transcriptional regulatory mechanisms have emerged as a critical component underlying the diversification and spatiotemporal control of the proteome during the establishment of precise neuronal connectivity. These mechanisms have been shown to be important for virtually all stages of assembling a neural network, from neurite guidance, branching, and growth to synapse morphogenesis and function. From the moment a gene is transcribed, it undergoes a series of post-transcriptional regulatory modifications in the nucleus and cytoplasm until its final deployment as a functional protein. Initially, a message is subjected to extensive structural regulation through alternative splicing, which is capable of greatly expanding the protein repertoire by generating, in some cases, thousands of functionally distinct isoforms from a single gene locus. Then, RNA packaging into neuronal transport granules and recognition by RNA-binding proteins and/or microRNAs is capable of restricting protein synthesis to selective locations and under specific input conditions. This ability of the post-transcriptional apparatus to expand the informational content of a cell and control the deployment of proteins in both spatial and temporal dimensions is a feature well adapted for the extreme morphological properties of neural cells. In this review, we describe recent advances in understanding how post-transcriptional regulatory mechanisms refine the proteomic complexity required for the assembly of intricate and specific neural networks.
Also flagged:Transferrin receptor 2TfR2cell cycleironglioblastomalipid
Journal Article2010-04-01✓ 1 SnippetCalzolari A, Larocca LM, Deaglio S, Finisguerra V, Boe A, Raggi C, Ricci-Vitani L, Pierconti F, Malavasi F, De Maria R, Testa U, Pallini R.
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…hemochromatosis…
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Under physiological conditions, transferrin receptor 2 (TfR2) is expressed in the liver and its balance is related to the cell cycle rather than to intracellular iron levels. We recently showed that TfR2 is highly expressed in glioblastoma cell lines. Here, we demonstrate that, in these cells, TfR2 appears to localize in lipid rafts, induces extracellular signal-regulated kinase 1/2 phosphorylation after transferrin binding, and contributes to cell proliferation, as shown by RNA silencing experiments. In vitro hypoxic conditions induce a significant TfR2 up-regulation, suggesting a role in tumor angiogenesis. As assessed by immunohistochemistry, the level of TfR2 expression in astrocytic tumors is related to histologic grade, with the highest expression observed in glioblastomas. The level of TfR2 expression represents a favorable prognostic factor, which is associated with the higher sensitivity to temozolomide of TfR2-positive tumor cells in vitro. The endothelial cells of glioblastoma vasculature also stain for TfR2, whereas those of the normal brain vessels do not. Importantly, TfR2 is expressed by the subpopulation of glioblastoma cells with properties of cancer-initiating cells. TfR2-positive glioblastoma cells retain their TfR2 expression on xenografting in immunodeficient mice. In conclusion, our observations demonstrate that TfR2 is a neoantigen for astrocytomas that seems attractive for developing target therapies.
Genetic aberrations involving the mixed lineage leukemia (MLL) gene are frequently diagnosed in infant acute lymphoblastic and acute myeloid leukemia. More than 60 fusion partner genes have been described at the molecular level, 31 of which have been characterized solely in infant leukemia cases. Here we describe a new MLL fusion partner gene, NEBL, which was identified in a case of acute myeloid leukemia in an infant. The chromosomal breakpoints of the MLL-NEBL and NEBL-MLL fusion genes were cloned by long-distance inverse polymerase chain reaction. The chromosomal breakpoints were located at 10p12, approximately 570 kb telomic of the MLLT10 (AF10) gene. AF10 and NEBL are localized in such close vicinity that they cannot be distinguished cytogenetically by G banding. Therefore, the combination of cytogenetic and independent molecular techniques such as long-distance inverse polymerase chain reaction are indispensable for the rapid identification and characterization of rare MLL rearrangements.
Also flagged:NPYalcoholbindingalcohol use disordersNeuropeptide Yaddiction
Journal Article2010-04-01No SnippetsLindell SG, Schwandt ML, Sun H, Sparenborg JD, Björk K, Kasckow JW, Sommer WH, Goldman D, Higley JD, Suomi SJ, Heilig M, Barr CS.
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<h4>Context</h4>Neuropeptide Y (NPY) counters stress and is involved in neuroadaptations that drive escalated alcohol drinking in rodents. In humans, low NPY expression predicts amygdala response and emotional reactivity. Genetic variation that affects the NPY system could moderate stress resilience and susceptibility to alcohol dependence.<h4>Objective</h4>To determine whether functional NPY variation influences behavioral adaptation to stress and alcohol consumption in a nonhuman primate model of early adversity (peer rearing).<h4>Design</h4>We sequenced the rhesus macaque NPY locus (rhNPY) and performed in silico analysis to identify functional variants. We performed gel shift assays using nuclear extract from testes, brain, and hypothalamus. Levels of NPY in cerebrospinal fluid were measured by radioimmunoassay, and messenger RNA levels were assessed in the amygdala using real-time polymerase chain reaction. Animals were exposed to repeated social separation stress and tested for individual differences in alcohol consumption. Animals were genotyped for -1002 T > G, and the data were analyzed using analysis of variance.<h4>Setting</h4>National Institutes of Health Animal Center. Subjects Ninety-six rhesus macaques. Main Outcome Measure Behavior arousal during social separation stress and ethanol consumption.<h4>Results</h4>The G allele altered binding of regulatory proteins in all nuclear extracts tested, and -1002 T > G resulted in lower levels of NPY expression in the amygdala. Macaques exposed to adversity had lower cerebrospinal fluid NPY levels and exhibited higher levels of arousal during stress, but only as a function of the G allele. We also found that stress-exposed G allele carriers consumed more alcohol and exhibited an escalation in intake over cycles of alcohol availability and deprivation.<h4>Conclusions</h4>Our results suggest a role for NPY promoter variation in the susceptibility to alcohol use disorders and point to NPY as a candidate for examining gene x environment interactions in humans.
Also flagged:lactationwarfarincoagulationgestationprothrombinfibrinogen
Journal Article2010-04-01✓ 1 SnippetOhishi T, Kitazawa T, Suzuki S, Nakamura D, Nishihara Y, Mochizuki M.
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Abstract)
…i-thrombin III concentration (ATIII).…
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Effects of pregnancy and lactation on warfarin-induced changes in blood coagulation-related parameters were examined in rats. Warfarin (0.5 mg/kg/day) was given orally to pregnant and non-pregnant rats for 3 days from gestation day (GD) 17 to 19 or to lactating and non-pregnant rats for 3 days from post partum day (PPD) 10 to 12. Blood samples were collected from the rats on the day following the last administration (GD 20 or PPD 13) to measure prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (FIB), thrombotest (TBT), factor VII and X activities and anti-thrombin III concentration (ATIII). Administration of warfarin to non-pregnant rats resulted in significant prolongation of APTT and TBT and significant decreases in factor VII and X activities. On the other hand, similar but not significant changes were observed in pregnant rats and similar significant but less prominent changes were observed in lactating rats. The reduction of the anticoagulant effects of warfarin may partially be related to high plasma 17beta-estradiol concentration in pregnant rats and to high plasma prolactin concentration in lactating rats, respectively.
Also flagged:Gene expressioniron oxidezinc-binding proteinsRnf138Abcc4polymerase
Journal Article2010-04-01✓ 2 SnippetsKedziorek DA, Muja N, Walczak P, Ruiz-Cabello J, Gilad AA, Jie CC, Bulte JW.
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…hemochromatosis…
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With MRI (stem) cell tracking having entered the clinic, studies on the cellular genomic response toward labeling are warranted. Gene expression profiling was applied to C17.2 neural stem cells following superparamagnetic iron oxide/PLL (poly-L-lysine) labeling over the course of 1 week. Relative to unlabeled cells, less than 1% of genes (49 total) exhibited greater than 2-fold difference in expression in response to superparamagnetic iron oxide/PLL labeling. In particular, transferrin receptor 1 (Tfrc) and heme oxygenase 1 (Hmox1) expression was downregulated early, whereas genes involved in lysosomal function (Sulf1) and detoxification (Clu, Cp, Gstm2, Mgst1) were upregulated at later time points. Relative to cells treated with PLL only, cells labeled with superparamagnetic iron oxide/PLL complexes exhibited differential expression of 1399 genes. Though these differentially expressed genes exhibited altered expression over time, the overall extent was limited. Gene ontology analysis of differentially expressed genes showed that genes encoding zinc-binding proteins are enriched after superparamagnetic iron oxide/PLL labeling relative to PLL only treatment, whereas members of the apoptosis/programmed cell death pathway did not display increased expression. Overexpression of the differentially expressed genes Rnf138 and Abcc4 were confirmed by quantitative real-time polymerase chain reaction. These results demonstrate that, although early reactions responsible for iron homeostasis are induced, overall neural stem cell gene expression remains largely unaltered following superparamagnetic iron oxide/PLL labeling.
Also flagged:zinc/R-type voltage-gated Ca(2+) channelsGABA-AGABA-C receptorsnickelsecretion
Journal Article2010-04-01No SnippetsSiapich SA, Wrubel H, Albanna W, Alnawaiseh M, Hescheler J, Weiergräber M, Lüke M, Schneider T.
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<h4>Purpose</h4>NiCl(2) (15 microM) enhances the ERG b-wave amplitude of vertebrate retina, up to 1.5-fold by blocking E/R-type voltage-gated Ca(2+) channels, which is mediated by blocking the release of GABA onto ionotropic GABA-A and GABA-C receptors. In vivo, it is likely that zinc, rather than nickel ions, may be involved in the modulation of retinal signalling. Therefore, we tested the effect of both, ZnCl(2) (10 to 500 microM) and DEDTC (100 to 500 microM), which chelates zinc ions for the capacity to influence the ERG b-wave amplitude.<h4>Methods</h4>Transretinal potentials from the isolated bovine retina were recorded as electroretinograms and Ca(2+) inward currents by patch-clamp recordings of stably Ca(v)2.3 transfected HEK-293 cells, yielding an IC(50) value of 5.3 microM for ZnCl(2).<h4>Results</h4>ZnCl(2) (10-15 microM) increased the b-wave amplitude by 1.52-fold +/- 0.12 (n = 6 retinas), which was partially reversible upon washout. The same 1.5-fold stimulation of the b-wave amplitude was reported recently for 15 microM NiCl(2). The superfusion of isolated retinas by DEDTC (100 microM) caused a transient decrease of the ERG b-wave amplitude (0.75-fold +/- 0.06; n = 4), suggesting that the co-secretion of Zn(2+) ions may occur under scotopic conditions.<h4>Conclusion</h4>The stimulatory effect of ZnCl(2) on the ERG b-wave amplitude resembles the stimulatory effect of NiCl(2) and may be mediated rather by the NiCl(2)-sensitive, Ca(v)2.3 E-/R-type voltage-gated Ca(2+) channels than by NiCl(2)-sensitive T-type channels.
Also flagged:Prdm1Blimp-1embryogenesiszinc-finger transcriptional repressorBlimp1myosin heavy chain
Journal Article2010-04-01✓ 1 SnippetBeermann ML, Ardelt M, Girgenrath M, Miller JB.
In-Text Gene Mentions
Introduction)
…and by liftingSox6-mediated repression of slow…
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<h4>Background</h4>Multiple types of fast and slow skeletal muscle fibers form during early embryogenesis in vertebrates. In zebrafish, formation of the earliest slow myofibers in fin muscles requires expression of the zinc-finger transcriptional repressor Prdm1 (also known as Blimp1). To further understand how the role of Prdm1 in early myogenesis may vary through evolution and during development, we have now analyzed Prdm1 expression in the diverse types of myotubes that form in culture from somitic, embryonic, and fetal chicken myoblasts.<h4>Principal findings</h4>In cultures of somitic, embryonic limb, and fetal limb chicken cells, we found that Prdm1 was expressed in all of the differentiated muscle cells that formed, including those that expressed only fast myosin heavy chain isoforms, as well as those that co-expressed both fast and slow myosin heavy chain isoforms. Prdm1 was also expressed in Pax7-positive myoblasts, as well as in non-myogenic cells in the cultures. Furthermore, though all differentiated cells in control somite cultures co-expressed fast and slow myosin heavy chains, antisense knockdown of Prdm1 expression inhibited the formation of these co-expressing cells in somite cultures.<h4>Conclusions</h4>In chicken myogenic cell cultures, Prdm1 was expressed in most Pax7-positive myoblasts and in all differentiated muscle cells, irrespective of the developmental stage of cell donor or the pattern of fast and slow myosin heavy chains expressed in the differentiated cells that were formed. Thus, Prdm1 was expressed in myogenic cells prior to terminal differentiation; and, after differentiation, Prdm1 expression was not limited to cells that expressed slow myosin heavy chain isoforms. In addition, Prdm1 appeared to be required for differentiation of the somitic myocytes, which are the earliest myocytes to form in the avian embryo.
Also flagged:chronic hepatitis Cinterferonironmetabolismribaviringenotype 1 infection
Journal Article2010-04-01✓ 1 SnippetJaroszewicz J, Rogalska M, Flisiak I, Flisiak R.
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…HFE…
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<h4>Aim</h4>To assess serum concentrations of prohepcidin in chronic hepatitis C individuals and evaluate their associations with disease activity and efficacy of pegylated interferon (PEG-IFN)/ribavirin (RBV) therapy.<h4>Methods</h4>Prohepcidin was measured in sera of 53 chronic hepatitis C patients. Concentrations of prohepcidin and other iron metabolism markers were analyzed at 9 time points before, during and after the end of antiviral therapy.<h4>Results</h4>In hepatitis C virus (HCV) genotype 1-infected individuals, a gradual decrease of prohepcidin during antiviral therapy was observed in responders (88.8 +/- 14.7 ng/mL before therapy vs 60.6 +/- 0.3 ng/mL in the 48th wk, P = 0.04). In contrast, no decrease was observed in non-responders. A similar association was observed in HCV genotype 3a individuals, with a statistically significant decline in serum prohepcidin only in the responder group (99.5 +/- 5.2 ng/mL at baseline vs 72.7 +/- 6.1 ng/mL in the 24th wk, P = 0.01). Moreover, HCV-RNA at week 12 of therapy was positively correlated with baseline (R = 0.63, P < 0.005) and week 12 (R = 0.60, P = 0.01) serum prohepcidin concentrations in HCV genotype 1 infection.<h4>Conclusion</h4>Successful PEG-IFN/RBV therapy results in a decline of serum prohepcidin concentration in chronic hepatitis C, which may suggest a direct effect of HCV on iron metabolism at the prohormonal level of hepcidin.
Also flagged:EGFRHER2AEE788ERER-positive breast canceroestrogen receptor
Journal Article2010-04-01No SnippetsEvans AH, Pancholi S, Farmer I, Thornhill A, Evans DB, Johnston SR, Dowsett M, Martin LA.
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<h4>Background</h4>Cross-talk between receptor tyrosine kinases and the oestrogen receptor (ER) is implicated in resistance to endocrine therapy. We investigated whether AEE788 (a combined inhibitor of EGFR, HER2 and VEGFR) plus tamoxifen or letrozole enhanced the individual anti-tumour effects of these agents.<h4>Methods</h4>Breast cancer cell lines modelling endocrine-resistant and -sensitive disease were engineered to express aromatase (A) and examined using proliferation, western blotting and ER-alpha transcription assays.<h4>Results</h4>AEE788 enhanced the anti-proliferative effect of tamoxifen and letrozole in ER(+) cell lines (MCF-7 2A, ZR75.1 A3 and BT474 A3). This associated with an elevated G1 arrest and nuclear accumulation of p27. It is noteworthy that AEE788 alone or in combination with endocrine therapy increased the expression of progesterone receptor (PGR) and TFF1 in BT474 A3 cells. This may indicate a mechanism of resistance to AEE788 in ER(+)/HER2(+) breast cancers. In a ZR75.1 A3 xenograft, AEE788 alone or in combination with tamoxifen provided no further benefit compared with letrozole. However, letrozole plus AEE788 produced a significantly greater inhibition of tumour growth compared with letrozole alone.<h4>Conclusion</h4>These data suggest that AEE788 plus letrozole in breast cancer overexpressing HER2 may provide superior anti-tumour activity, compared with single agents.
Also flagged:calmodulin-dependent protein kinase IICaMKIICaMKII-associated protein densindendritic spines2+Ca 2+
Journal Article2010-04-01✓ 2 SnippetsJenkins MA, Christel CJ, Jiao Y, Abiria S, Kim KY, Usachev YM, Obermair GJ, Colbran RJ, Lee A.
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…2+ Channels byDensinand Ca 2+…
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Ca(v)1 (L-type) channels and calmodulin-dependent protein kinase II (CaMKII) are key regulators of Ca(2+) signaling in neurons. CaMKII directly potentiates the activity of Ca(v)1.2 and Ca(v)1.3 channels, but the underlying molecular mechanisms are incompletely understood. Here, we report that the CaMKII-associated protein densin is required for Ca(2+)-dependent facilitation of Ca(v)1.3 channels. While neither CaMKII nor densin independently affects Ca(v)1.3 properties in transfected HEK293T cells, the two together augment Ca(v)1.3 Ca(2+) currents during repetitive, but not sustained, depolarizing stimuli. Facilitation requires Ca(2+), CaMKII activation, and its association with densin, as well as densin binding to the Ca(v)1.3 alpha(1) subunit C-terminal domain. Ca(v)1.3 channels and densin are targeted to dendritic spines in neurons and form a complex with CaMKII in the brain. Our results demonstrate a novel mechanism for Ca(2+)-dependent facilitation that may intensify postsynaptic Ca(2+) signals during high-frequency stimulation.
Also flagged:metabolismironoligonucleotidepolymeraseHHHereditary Hemochromatosis
Journal Article2010-04-01✓ 5 SnippetsChandrasekharan S, Pitlick E, Heaney C, Cook-Deegan R.
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Abstract)
…Most initial testing for hereditary hemochromatosis is biochemical, but HFE deoxyribonucleic acid testing or genotyping is used to confirm a diagnosis of inherited hemochromatosis.…
Abstract)
…HFE gene are the single most common cause of hereditary hemochromatosis…
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…hereditary hemochromatosis is biochemical, but HFE…
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…HFE deoxyribonucleic acid testing or genotyping is used to confirm a diagnosis of inherited hemochromatosis…
Abstract)
…Mutations in theHFEgene are the…
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Hereditary hemochromatosis is an iron metabolism disorder that leads to excess iron buildup, especially in the heart, liver, and pancreas. Mutations in the HFE gene are the single most common cause of hereditary hemochromatosis, which can be treated effectively if diagnosed early. Patents cover the HFE gene, related proteins, screening methods, and testing kits. Most initial testing for hereditary hemochromatosis is biochemical, but HFE deoxyribonucleic acid testing or genotyping is used to confirm a diagnosis of inherited hemochromatosis. Concerns over patents covering HFE testing emerged in 2002, when scholars argued that exclusive licensing and the patent-enabled sole provider model then in place led to high prices and limited access. Critics of the sole provider model noted that the test was available at multiple laboratories before the enforcement of patents. By 2007, however, Bio-Rad Limited, acquired the key intellectual property and sublicensed it widely. In part because of broad, nonexclusive licensing, there are now multiple providers and testing technologies, and research continues. This case study illustrates how both changes in intellectual property ownership and evolving clinical utility of HFE genetic testing in the last decade have effected the licensing of patents and availability of genetic testing.
Also flagged:cancertumorstumorPALB2pancreatic cancersmall
Journal Article2010-04-01No SnippetsInternational Cancer Genome Consortium, Hudson TJ, Anderson W, Artez A, Barker AD, Bell C, Bernabé RR, Bhan MK, Calvo F, Eerola I, Gerhard DS, Guttmacher A, Guyer M, Hemsley FM, Jennings JL, Kerr D, Klatt P, Kolar P, Kusada J, Lane DP, Laplace F, Youyong L, Nettekoven G, Ozenberger B, Peterson J, Rao TS, Remacle J, Schafer AJ, Shibata T, Stratton MR, Vockley JG, Watanabe K, Yang H, Yuen MM, Knoppers BM, Bobrow M, Cambon-Thomsen A, Dressler LG, Dyke SO, Joly Y, Kato K, Kennedy KL, Nicolás P, Parker MJ, Rial-Sebbag E, Romeo-Casabona CM, Shaw KM, Wallace S, Wiesner GL, Zeps N, Lichter P, Biankin AV, Chabannon C, Chin L, Clément B, de Alava E, Degos F, Ferguson ML, Geary P, Hayes DN, Hudson TJ, Johns AL, Kasprzyk A, Nakagawa H, Penny R, Piris MA, Sarin R, Scarpa A, Shibata T, van de Vijver M, Futreal PA, Aburatani H, Bayés M, Botwell DD, Campbell PJ, Estivill X, Gerhard DS, Grimmond SM, Gut I, Hirst M, López-Otín C, Majumder P, Marra M, McPherson JD, Nakagawa H, Ning Z, Puente XS, Ruan Y, Shibata T, Stratton MR, Stunnenberg HG, Swerdlow H, Velculescu VE, Wilson RK, Xue HH, Yang L, Spellman PT, Bader GD, Boutros PC, Campbell PJ, Flicek P, Getz G, Guigó R, Guo G, Haussler D, Heath S, Hubbard TJ, Jiang T, Jones SM, Li Q, López-Bigas N, Luo R, Muthuswamy L, Ouellette BF, Pearson JV, Puente XS, Quesada V, Raphael BJ, Sander C, Shibata T, Speed TP, Stein LD, Stuart JM, Teague JW, Totoki Y, Tsunoda T, Valencia A, Wheeler DA, Wu H, Zhao S, Zhou G, Stein LD, Guigó R, Hubbard TJ, Joly Y, Jones SM, Kasprzyk A, Lathrop M, López-Bigas N, Ouellette BF, Spellman PT, Teague JW, Thomas G, Valencia A, Yoshida T, Kennedy KL, Axton M, Dyke SO, Futreal PA, Gerhard DS, Gunter C, Guyer M, Hudson TJ, McPherson JD, Miller LJ, Ozenberger B, Shaw KM, Kasprzyk A, Stein LD, Zhang J, Haider SA, Wang J, Yung CK, Cros A, Liang Y, Gnaneshan S, Guberman J, Hsu J, Bobrow M, Chalmers DR, Hasel KW, Joly Y, Kaan TS, Kennedy KL, Knoppers BM, Lowrance WW, Masui T, Nicolás P, Rial-Sebbag E, Rodriguez LL, Vergely C, Yoshida T, Grimmond SM, Biankin AV, Bowtell DD, Cloonan N, deFazio A, Eshleman JR, Etemadmoghadam D, Gardiner BB, Kench JG, Scarpa A, Sutherland RL, Tempero MA, Waddell NJ, Wilson PJ, McPherson JD, Gallinger S, Tsao MS, Shaw PA, Petersen GM, Mukhopadhyay D, Chin L, DePinho RA, Thayer S, Muthuswamy L, Shazand K, Beck T, Sam M, Timms L, Ballin V, Lu Y, Ji J, Zhang X, Chen F, Hu X, Zhou G, Yang Q, Tian G, Zhang L, Xing X, Li X, Zhu Z, Yu Y, Yu J, Yang H, Lathrop M, Tost J, Brennan P, Holcatova I, Zaridze D, Brazma A, Egevard L, Prokhortchouk E, Banks RE, Uhlén M, Cambon-Thomsen A, Viksna J, Ponten F, Skryabin K, Stratton MR, Futreal PA, Birney E, Borg A, Børresen-Dale AL, Caldas C, Foekens JA, Martin S, Reis-Filho JS, Richardson AL, Sotiriou C, Stunnenberg HG, Thoms G, van de Vijver M, van't Veer L, Calvo F, Birnbaum D, Blanche H, Boucher P, Boyault S, Chabannon C, Gut I, Masson-Jacquemier JD, Lathrop M, Pauporté I, Pivot X, Vincent-Salomon A, Tabone E, Theillet C, Thomas G, Tost J, Treilleux I, Calvo F, Bioulac-Sage P, Clément B, Decaens T, Degos F, Franco D, Gut I, Gut M, Heath S, Lathrop M, Samuel D, Thomas G, Zucman-Rossi J, Lichter P, Eils R, Brors B, Korbel JO, Korshunov A, Landgraf P, Lehrach H, Pfister S, Radlwimmer B, Reifenberger G, Taylor MD, von Kalle C, Majumder PP, Sarin R, Rao TS, Bhan MK, Scarpa A, Pederzoli P, Lawlor RA, Delledonne M, Bardelli A, Biankin AV, Grimmond SM, Gress T, Klimstra D, Zamboni G, Shibata T, Nakamura Y, Nakagawa H, Kusada J, Tsunoda T, Miyano S, Aburatani H, Kato K, Fujimoto A, Yoshida T, Campo E, López-Otín C, Estivill X, Guigó R, de Sanjosé S, Piris MA, Montserrat E, González-Díaz M, Puente XS, Jares P, Valencia A, Himmelbauer H, Quesada V, Bea S, Stratton MR, Futreal PA, Campbell PJ, Vincent-Salomon A, Richardson AL, Reis-Filho JS, van de Vijver M, Thomas G, Masson-Jacquemier JD, Aparicio S, Borg A, Børresen-Dale AL, Caldas C, Foekens JA, Stunnenberg HG, van't Veer L, Easton DF, Spellman PT, Martin S, Barker AD, Chin L, Collins FS, Compton CC, Ferguson ML, Gerhard DS, Getz G, Gunter C, Guttmacher A, Guyer M, Hayes DN, Lander ES, Ozenberger B, Penny R, Peterson J, Sander C, Shaw KM, Speed TP, Spellman PT, Vockley JG, Wheeler DA, Wilson RK, Hudson TJ, Chin L, Knoppers BM, Lander ES, Lichter P, Stein LD, Stratton MR, Anderson W, Barker AD, Bell C, Bobrow M, Burke W, Collins FS, Compton CC, DePinho RA, Easton DF, Futreal PA, Gerhard DS, Green AR, Guyer M, Hamilton SR, Hubbard TJ, Kallioniemi OP, Kennedy KL, Ley TJ, Liu ET, Lu Y, Majumder P, Marra M, Ozenberger B, Peterson J, Schafer AJ, Spellman PT, Stunnenberg HG, Wainwright BJ, Wilson RK, Yang H.
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The International Cancer Genome Consortium (ICGC) was launched to coordinate large-scale cancer genome studies in tumours from 50 different cancer types and/or subtypes that are of clinical and societal importance across the globe. Systematic studies of more than 25,000 cancer genomes at the genomic, epigenomic and transcriptomic levels will reveal the repertoire of oncogenic mutations, uncover traces of the mutagenic influences, define clinically relevant subtypes for prognosis and therapeutic management, and enable the development of new cancer therapies.
Also flagged:transcription factorBCL11AchromatinchromosomeHMG-box-containing transcription factorGATA1
Journal Article2010-04-01✓ 5 SnippetsXu J, Sankaran VG, Ni M, Menne TF, Puram RV, Kim W, Orkin SH.
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Abstract)
…These findings collectively demonstrate that transcriptional silencing of gamma-globin genes by BCL11A involves long-range interactions and cooperation with SOX6.…
The developmental switch from human fetal (gamma) to adult (beta) hemoglobin represents a clinically important example of developmental gene regulation. The transcription factor BCL11A is a central mediator of gamma-globin silencing and hemoglobin switching. Here we determine chromatin occupancy of BCL11A at the human beta-globin locus and other genomic regions in vivo by high-resolution chromatin immunoprecipitation (ChIP)-chip analysis. BCL11A binds the upstream locus control region (LCR), epsilon-globin, and the intergenic regions between gamma-globin and delta-globin genes. A chromosome conformation capture (3C) assay shows that BCL11A reconfigures the beta-globin cluster by modulating chromosomal loop formation. We also show that BCL11A and the HMG-box-containing transcription factor SOX6 interact physically and functionally during erythroid maturation. BCL11A and SOX6 co-occupy the human beta-globin cluster along with GATA1, and cooperate in silencing gamma-globin transcription in adult human erythroid progenitors. These findings collectively demonstrate that transcriptional silencing of gamma-globin genes by BCL11A involves long-range interactions and cooperation with SOX6. Our findings provide insight into the mechanism of BCL11A action and new clues for the developmental gene regulatory programs that function at the beta-globin locus.
Journal Article2010-04-01No SnippetsLiu JZ, Medland SE, Wright MJ, Henders AK, Heath AC, Madden PA, Duncan A, Montgomery GW, Martin NG, McRae AF.
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Human height and body mass index are influenced by a large number of genes, each with small effects, along with environment. To identify common genetic variants associated with these traits, we performed genome-wide association studies in 11,536 individuals composed of Australian twins, family members, and unrelated individuals at approximately 550,000 genotyped SNPs. We identified a single genome-wide significant variant for height (P value=1.06x10(-9)) located in HHIP, a well-replicated height-associated gene. Suggestive levels of association were found for other known genes associated with height (P values<1x10(-6)): ADAMTSL3, EFEMP1, GPR126, and HMGA2; and BMI (P values<1x10(-4)): FTO and MC4R. Together, these variants explain less than 2% of total phenotypic variation for height and 0.5% for BMI.
Also flagged:organellesmitochondriamitochondrialMfn1Mfn2mitochondrial GTPases
Journal Article2010-04-01No SnippetsChen H, Vermulst M, Wang YE, Chomyn A, Prolla TA, McCaffery JM, Chan DC.
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Mitochondria are highly mobile and dynamic organelles that continually fuse and divide. These processes allow mitochondria to exchange contents, including mitochondrial DNA (mtDNA). Here we examine the functions of mitochondrial fusion in differentiated skeletal muscle through conditional deletion of the mitofusins Mfn1 and Mfn2, mitochondrial GTPases essential for fusion. Loss of the mitofusins causes severe mitochondrial dysfunction, compensatory mitochondrial proliferation, and muscle atrophy. Mutant mice have severe mtDNA depletion in muscle that precedes physiological abnormalities. Moreover, the mitochondrial genomes of the mutant muscle rapidly accumulate point mutations and deletions. In a related experiment, we find that disruption of mitochondrial fusion strongly increases mitochondrial dysfunction and lethality in a mouse model with high levels of mtDNA mutations. With its dual function in safeguarding mtDNA integrity and preserving mtDNA function in the face of mutations, mitochondrial fusion is likely to be a protective factor in human disorders associated with mtDNA mutations.
Also flagged:adultheart diseasegene expressioncongenital heart diseasecardiomyopathiesheart failure
Journal Article2010-04-01✓ 1 SnippetLiu N, Olson EN.
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The heart, more than any other organ, requires precise functionality on a second-to-second basis throughout the lifespan of the organism. Even subtle perturbations in cardiac structure or function have catastrophic consequences, resulting in lethal forms of congenital and adult heart disease. Such intolerance of the heart to variability necessitates especially robust regulatory mechanisms to govern cardiac gene expression. Recent studies have revealed central roles for microRNAs (miRNAs) as governors of gene expression during cardiovascular development and disease. The integration of miRNAs into the genetic circuitry of the heart provides a rich and robust array of regulatory interactions to control cardiac gene expression. miRNA regulatory networks also offer opportunities for therapeutically modulating cardiac function through the manipulation of pathogenic and protective miRNAs. We discuss the roles of miRNAs as regulators of cardiac form and function, unresolved questions in the field, and issues for the future.
Also flagged:neurodegenerative diseaseslocalizationbindingneuroblastomamineral1-propanol
Journal Article2010-04-01✓ 3 SnippetsRamdzan YM, Nisbet RM, Miller J, Finkbeiner S, Hill AF, Hatters DM.
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Abstract)
…Sensors for mutant huntingtin, which forms aggregates in Huntington's disease, were made by introducing a tetracysteine motif into huntingtin that becomes occluded from binding biarsenical fluorophores in oligomers, but not monomers.…
Abstract)
…Up to 70% of the diffusely distributed huntingtin molecules appeared as submicroscopic oligomers in individual neuroblastoma cells expressing mutant huntingtin.…
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…Htt…
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Proteins prone to misfolding form large macroscopic deposits in many neurodegenerative diseases. Yet the in situ aggregation kinetics remains poorly understood because of an inability to demarcate precursor oligomers from monomers. We developed a strategy for mapping the localization of soluble oligomers and monomers directly in live cells. Sensors for mutant huntingtin, which forms aggregates in Huntington's disease, were made by introducing a tetracysteine motif into huntingtin that becomes occluded from binding biarsenical fluorophores in oligomers, but not monomers. Up to 70% of the diffusely distributed huntingtin molecules appeared as submicroscopic oligomers in individual neuroblastoma cells expressing mutant huntingtin. We anticipate the sensors to enable insight into cellular mechanisms mediated by oligomers and monomers and for the approach to be adaptable more generally in the study of protein self-association.
Also flagged:degradationcytosolAlfyp62SQSTM1polyglutamine
Journal Article2010-04-01✓ 1 SnippetFilimonenko M, Isakson P, Finley KD, Anderson M, Jeong H, Melia TJ, Bartlett BJ, Myers KM, Birkeland HC, Lamark T, Krainc D, Brech A, Stenmark H, Simonsen A, Yamamoto A.
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There is growing evidence that macroautophagic cargo is not limited to bulk cytosol in response to starvation and can occur selectively for substrates, including aggregated proteins. It remains unclear, however, whether starvation-induced and selective macroautophagy share identical adaptor molecules to capture their cargo. Here, we report that Alfy, a phosphatidylinositol 3-phosphate-binding protein, is central to the selective elimination of aggregated proteins. We report that the loss of Alfy inhibits the clearance of inclusions, with little to no effect on the starvation response. Alfy is recruited to intracellular inclusions and scaffolds a complex between p62(SQSTM1)-positive proteins and the autophagic effectors Atg5, Atg12, Atg16L, and LC3. Alfy overexpression leads to elimination of aggregates in an Atg5-dependent manner and, likewise, to protection in a neuronal and Drosophila model of polyglutamine toxicity. We propose that Alfy plays a key role in selective macroautophagy by bridging cargo to the molecular machinery that builds autophagosomes.
Also flagged:oxymatrinesurface antigene antigenHBeAgpolymerasenucleocapsid
Journal Article2010-04-01No SnippetsXu WS, Zhao KK, Miao XH, Ni W, Cai X, Zhang RQ, Wang JX.
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<h4>Aim</h4>To determine the antiviral mechanism or target of oxymatrine against hepatitis B virus (HBV).<h4>Methods</h4>HepG2.2.15 cells were incubated with culture medium containing 500 microg/mL of oxymatrine for 2 and 5 d. The surface antigen of HBV (HBsAg) and e antigen of HBV (HBeAg) in supernatant were determined by ELISA. HBV DNA in supernatant, and intracellular covalently closed circular DNA (cccDNA), relaxed circular DNA (rcDNA) and pregenomic RNA (pgRNA) were quantified by specific real-time polymerase chain reaction (PCR) or reverse transcription (RT)-PCR.<h4>Results</h4>Treatment with oxymatrine for 2 d and 5 d reduced the production of HBV by the cell line, as indicated by the decline of HBsAg (22.67%, t = 5.439, P = 0.0322 and 22.39%, t = 5.376, P = 0.0329, respectively), HBeAg (55.34%, t = 9.859, P = 0.0101 and 43.97%, t = 14.080, P = 0.0050) and HBV DNA (40.75%, t = 4.570, P = 0.0447 and 75.32%, t = 14.460, P = 0.0047) in the supernatant. Intracellular cccDNA was also markedly reduced by 63.98% (t = 6.152, P = 0.0254) and 80.83% (t = 10.270, P = 0.0093), and intracellular rcDNA by 34.35% (t = 4.776, P = 0.0413) and 39.24% (t = 10.050, P = 0.0097). In contrast, intracellular pgRNA increased by 6.90-fold (t = 8.941, P = 0.0123) and 3.18-fold (t = 7.432, P = 0.0176) after 500 microg/mL of oxymatrine treatment for 2 d and 5 d, respectively.<h4>Conclusion</h4>Oxymatrine may inhibit the replication of HBV by interfering with the process of packaging pgRNA into the nucleocapsid, or inhibiting the activity of the viral DNA polymerase.
Also flagged:alcoholic liver diseaseHereditary hemochromatosisironmetabolismliver fibrosispolymerase
Journal Article2010-04-01✓ 5 SnippetsRaszeja-Wyszomirska J, Kurzawski G, Zawada I, Suchy J, Lubinski J, Milkiewicz P.
In-Text Gene Mentions
Abstract)
…Hereditary hemochromatosis has been linked with C282Y and H63D mutations of the HFE gene encoding human hemochromatosis protein.…
Abstract)
…The prevalence of HFE mutations in ALD patients is similar to that observed in healthy subjects and comparable to the prevalence in other Central European countries.…
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…the context of HFE gene mutation in ALD patients…
Title)
…HFE gene mutations in patients with alcoholic liver disease.…
Abstract)
…<h4>Introduction</h4>Hereditary hemochromatosis has been linked with C282Y and H63D mutations of the HFE gene encoding human hemochromatosis protein.…
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<h4>Introduction</h4>Hereditary hemochromatosis has been linked with C282Y and H63D mutations of the HFE gene encoding human hemochromatosis protein. It is genetic disorder of iron metabolism, leading to iron accumulation and increased liver fibrosis. The association between alcoholic liver disease (ALD) and HFE gene mutations remains unclear and requires clarification.<h4>Objectives</h4>The aim of the study was to determine the prevalence of C282Y and H63D mutations in patients with ALD and healthy individuals and to analyze laboratory data in the context of HFE gene mutation in ALD patients.<h4>Patients and methods</h4>We analyzed 119 patients with ALD. The control group comprised 1516 DNA samples obtained either from cord blood or healthy subjects from the records of general practitioners. HFE mutations were detected using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.<h4>Results</h4>Among the ALD patients, 0.84% were homozygous and 3.36% were heterozygous for the C282Y mutation, while 5.04% were homozygous and 21.85% heterozygous for the H63D mutation. There was 1 C282Y/H63D compound heterozygote in the ALD group. In the control group, 2 homozygotes and 117 heterozygotes for the C282Y mutation were identified. As for the H63D mutation, 2.5% homozygotes, 25% heterozygotes, and 1.4% compound heterozygotes were found. There was a trend towards a more common occurrence of ALD patients homozygous for the H63D mutation. Patients with H63D genotype had higher total and low-density lipoprotein cholesterol.<h4>Conclusions</h4>The prevalence of HFE mutations in ALD patients is similar to that observed in healthy subjects and comparable to the prevalence in other Central European countries. Our findings on lipid disturbances in the H63D heterozygotes are potentially interesting and require further studies on larger patient groups.
Also flagged:colorectal adenocarcinomareverse transcriptionGAPDHcolorectal tumourstumoursL
Journal Article2010-04-01✓ 1 SnippetKontos CK, Papadopoulos IN, Fragoulis EG, Scorilas A.
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S I O 001029)
…In an attempt to refine prognostication and predict the benefit derived from systemic treatment, several protein and genetic markers have been evaluated in patients with CRC, including allelic loss of chromosome 18q (Jen et al, 1994; Martinez-Lopez et al, 1998; Ogunbiyi et al, 1998; Popat and Houlston, 2005), absence of the deleted in colorectal carcinoma (DCC) protein (Shibata et al, 1996; Reymond et al, 1998; Popat and Houlston, 2005), decreased SMAD4 mRNA expression (Boulay et al, 2002; Alazzouzi et al, 2005), expression and/or abnormalities of cytoplasmic oncoprotein p53 (TP53) (Sun et al, 1992; Munro et al, 2005; Russo et al, 2005), protein levels and/or gene haplotype of thymidylate synthetase (TYMS) (Popat et al, 2004; Suh et al, 2005; Tsourouflis et al, 2008), microsatellite instability (MSI) (Gryfe et al, 2000; Popat et al, 2005), and chromosomal instability (CIN) (Walther et al, 2008).…
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<h4>Background</h4>L-DOPA decarboxylase (DDC) is an enzyme that catalyses, mainly, the decarboxylation of L-DOPA to dopamine and was found to be involved in many malignancies. The aim of this study was to investigate the mRNA expression levels of the DDC gene and to evaluate its clinical utility in tissues with colorectal adenocarcinoma.<h4>Methods</h4>Total RNA was isolated from colorectal adenocarcinoma tissues of 95 patients. After having tested RNA quality, we prepared cDNA by reverse transcription. Highly sensitive quantitative real-time PCR method for DDC mRNA quantification was developed using the SYBR Green chemistry. GAPDH served as a housekeeping gene. Relative quantification analysis was performed using the comparative C(T) method (2(-DeltaDeltaC(T))).<h4>Results</h4>DDC mRNA expression varied remarkably among colorectal tumours examined in this study. High DDC mRNA expression levels were found in well-differentiated and Dukes' stage A and B tumours. Kaplan-Meier survival curves showed that patients with DDC-positive tumours have significantly longer disease-free survival (P=0.009) and overall survival (P=0.027). In Cox regression analysis of the entire cohort of patients, negative DDC proved to be a significant predictor of reduced disease-free (P=0.021) and overall survival (P=0.047).<h4>Conclusions</h4>The results of the study suggest that DDC mRNA expression may be regarded as a novel potential tissue biomarker in colorectal adenocarcinoma.
Also flagged:Gene expressionpolymeraseMajor Depressionpsychiatric disordersMDreverse transcription
Journal Article2010-04-01No SnippetsMehta D, Mehta D, Menke A, Binder EB.
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The dramatic technical advances in methods to measure gene expression on a genome-wide level thus far have not been paralleled by breakthrough discoveries in psychiatric disorders-including major depression (MD)-using these hypothesis-free approaches. In this review, we first describe the methodologic advances made in gene expression analysis, from quantitative polymerase chain reaction to next-generation sequencing. We then discuss issues in gene expression experiments specific to MD, ranging from the choice of target tissues to the characterization of the case group. We provide a synopsis of the gene expression studies published thus far for MD, with a focus on studies using mRNA microarray methods. Finally, we discuss possible new strategies for the gene expression studies in MD that circumvent some of the addressed issues.
…Mutations in DCC cause congenital mirror movements.…
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…We found that affected individuals carried protein-truncating mutations in DCC (deleted in colorectal carcinoma), a gene on chromosome 18q21.2 that encodes a receptor for netrin-1, a diffusible protein that helps guide axon growth across the midline.…
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…Mutations inDCCcause congenital mirror…
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…rotein-truncating mutations inDCC(deleted in colorectal…
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…of the mutantDCCprotein from the…
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Mirror movements are involuntary contralateral movements that mirror voluntary ones and are often associated with defects in midline crossing of the developing central nervous system. We studied two large families, one French Canadian and one Iranian, in which isolated congenital mirror movements were inherited as an autosomal dominant trait. We found that affected individuals carried protein-truncating mutations in DCC (deleted in colorectal carcinoma), a gene on chromosome 18q21.2 that encodes a receptor for netrin-1, a diffusible protein that helps guide axon growth across the midline. Functional analysis of the mutant DCC protein from the French Canadian family revealed a defect in netrin-1 binding. Thus, DCC has an important role in lateralization of the human nervous system.
Also flagged:alcoholalcoholic cirrhosisliver diseaseaddictionalcoholic liver diseasealcohol abuse
Journal Article2010-04-01✓ 1 SnippetKarim Z, Intaraprasong P, Scudamore CH, Erb SR, Soos JG, Cheung E, Cooper P, Buzckowski AK, Chung SW, Steinbrecher UP, Yoshida EM.
In-Text Gene Mentions
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…hemochromatosis…
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<h4>Background</h4>End-stage alcoholic liver disease is common, with many of these patients referred for liver transplantation (LT). Alcohol relapse after LT can have detrimental outcomes such as graft loss and can contribute to a negative public perception of LT.<h4>Objective</h4>To identify factors that predict the recurrence of harmful alcohol consumption after LT.<h4>Methods</h4>A total of 80 patients who underwent LT for alcoholic cirrhosis or had significant alcohol consumption in association with another primary liver disease, from July 1992 to June 2006 in British Columbia, were retrospectively evaluated by chart review. Several demographic-, psychosocial- and addiction-related variables were studied. Univariate and multivariate logistic regression analyses were used to test possible associations among the variables studied and a return to harmful drinking after LT.<h4>Results</h4>The relapse rate of harmful alcohol consumption post-liver transplant was 10%, with two patient deaths occurring directly as a result of alcohol relapse. Univariate analysis revealed relapse was significantly associated with pretransplant abstinence of less than six months (P=0.003), presence of psychiatric comorbidities (P=0.016), female sex (P=0.019) and increased personal stressors (P=0.044), while age at transplant of younger than 50 years approached significance (P=0.054). Multivariate logistic regression analysis revealed the following independent factors for relapse: pretransplant abstinence of less than six months (OR 77.07; standard error 1.743; P=0.013) and female sex (OR 18.80; standard error 1.451; P=0.043).<h4>Conclusion</h4>The findings of the present study strongly support a required minimum of six months of abstinence before LT because duration of abstinence was found to be the strongest predictor of recidivism. Female sex, younger age at transplant and psychiatric comorbidities were also associated with relapse to harmful drinking.
Also flagged:thrombotic microangiopathygastric cancergastric carcinomathrombotic thrombocytopenic purpuragastric adenocarcinomatumor
Journal Article2010-04-01✓ 3 SnippetsVasko R, Koziolek M, Füzesi L, König F, Strutz F, Müller GA.
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…DCC tumor…
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…KRAS oncogene and aberrations in DCC tumor…
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…and aberrations inDCCtumor suppressor gene,…
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We report a case of a 27-year-old female with thrombotic microangiopathy as an initial presentation of an unexpected disseminated gastric carcinoma. Based on clinical features and laboratory findings, thrombotic thrombocytopenic purpura (TTP) was diagnosed and plasma exchange started. However, she had responded poorly to plasmapheresis, developed multiorgan failure and died 72 h after admission. Autopsy revealed a disseminated gastric adenocarcinoma with metastatic infiltration of dura mater and disseminated tumor cell emboli in the microcirculation of the liver and lungs. Genetic analysis revealed amplification of KRAS oncogene and aberrations in DCC tumor suppressor gene, which can explain the young age and advanced disease at presentation. The role of plasmapheresis in cancer-associated TTP is uncertain. Plasmapheresis delivers fresh coagulation factors and may theoretically promote microthrombi formation and lead to worsening of the disease. Thrombotic thrombocytopenic purpura seems to be a late and prognostically poor manifestation of an underlying malignancy, with majority of patients dying soon after diagnosis. It is important to be aware of this possibility in thrombotic microangiopathy, especially with atypical features and poor response to standard treatment.
Also flagged:lymphoid myeloid leukemiaAF10acute leukemiasmyeloid leukemiasCALMchromosomes
Journal Article2010-04-01No SnippetsHuh JY, Chung S, Oh D, Kang MS, Eom HS, Cho EH, Han MH, Kong SY.
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The translocation t(10;11)(p13;q14q21) has been found to be recurrent in acute lymphoblastic and myeloid leukemias, and results in the fusion of the clathrin assembly lymphoid myeloid leukemia (CALM) gene with the AF10 gene; these genes are present on chromosomes 11 and 10, respectively. Because the CALM-AF10 rearrangement is a rare chromosomal abnormality, it is not included in routine molecular tests for acute leukemia. Here, we describe the cases of 2 patients with the CALM-AF10 fusion gene. The first patient (case 1) was diagnosed with T-cell ALL, and the second patient (case 2) was diagnosed with AML. Both patient samples showed expression of the homeobox A gene cluster and the histone methyltransferase hDOT1L, which suggests that they mediate leukemic transformation in CALM-AF10-positive and mixed-lineage leukemia-AF10-positive leukemias. Both patients achieved complete remission after induction chemotherapy. The first patient (case 1) relapsed after double-unit cord blood transplantation; there was no evidence of relapse in the second patient (case 2) after allogenic peripheral blood stem cell transplantation. Since CALM-AF10- positive leukemias have been shown to have poor prognosis with conventional therapy, molecular tests for CALM-AF10 rearrangement would be necessary to detect minimal residual disease during follow-up.
…Although we identified no neurological explanation for the decreased life expectancy of HD-N171-82Q mice with partial depletion of CBP, the data are consistent with the notion that CBP function mitigates mutant htt toxicity by a currently unidentified mechanism.…
Abstract)
…that mutant huntingtin (htt) interferes with cyclic…
Abstract)
…fragments of mutanthtt, histone deacetylase inhibito…
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…the striatum, mutanthttinclusion formation, or…
Abstract)
…confirmed that mutanthttinclusions recruit human…
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Previous studies have reported that mutant huntingtin (htt) interferes with cyclic AMP response element binding protein binding protein (CBP)-mediated transcription, possibly by inhibiting the acetylation of histones. In Drosophila models that express fragments of mutant htt, histone deacetylase inhibitors reverse deficits in histone acetylation, rescue photoreceptor degeneration, and prolong their survival. These compounds also improve motor deficits in a transgenic mouse model of Huntington disease (HD). To determine whether endogenous CBP depletion contributes to HD pathogenesis, we crossed HD-N171-82Q transgenic mice with mice harboring a disrupted CBP gene and produced mice with partial (50%) depletion of CBP. This reduction of CBP levels decreased the life expectancy of the HD-N171-82Q Line 6 mouse model. The loss of CBP had no obvious impact on the severity of motor impairment, degeneration of the striatum, mutant htt inclusion formation, or global levels of acetylated histones H3 or H4 in brain. In cell models, we confirmed that mutant htt inclusions recruit human CBP but found no evidence for interactions between soluble forms of mutant htt and CBP. Although we identified no neurological explanation for the decreased life expectancy of HD-N171-82Q mice with partial depletion of CBP, the data are consistent with the notion that CBP function mitigates mutant htt toxicity by a currently unidentified mechanism.
Also flagged:axondendritesaxonsaction potentialssynapticextracellular
Journal Article2010-04-01No SnippetsPolleux F, Snider W.
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The ability of neurons to form a single axon and multiple dendrites underlies the directional flow of information transfer in the central nervous system. Dendrites and axons are molecularly and functionally distinct domains. Dendrites integrate synaptic inputs, triggering the generation of action potentials at the level of the soma. Action potentials then propagate along the axon, which makes presynaptic contacts onto target cells. This article reviews what is known about the cellular and molecular mechanisms underlying the ability of neurons to initiate and extend a single axon during development. Remarkably, neurons can polarize to form a single axon, multiple dendrites, and later establish functional synaptic contacts in reductionist in vitro conditions. This approach became, and remains, the dominant model to study axon initiation and growth and has yielded the identification of many molecules that regulate axon formation in vitro (Dotti et al. 1988). At present, only a few of the genes identified using in vitro approaches have been shown to be required for axon initiation and outgrowth in vivo. In vitro, axon initiation and elongation are largely intrinsic properties of neurons that are established in the absence of relevant extracellular cues. However, the importance of extracellular cues to axon initiation and outgrowth in vivo is emerging as a major theme in neural development (Barnes and Polleux 2009). In this article, we focus our attention on the extracellular cues and signaling pathways required in vivo for axon initiation and axon extension.
…female patient withhemochromatosis: a zoonosis?].…
Abstract)
…history included genetichemochromatosis(without cirrhosis).…
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A 58-year-old female patient was transferred by her general practitioner with fatigue, nausea and icterus which had begun 2 weeks prior to admission. Laboratory results revealed acute hepatitis (ALAT [alanine aminotransferase] 3,871 U/l, ASAT [aspartate aminotransferase] 2,004 U/l, bilirubin 6.7 mg/dl, gamma-GT [gamma-glutamyl transferase] 503 U/l). The patient's medical history included genetic hemochromatosis (without cirrhosis). Hepatitis A to C, infection with herpesviruses or Leptospira interrogans were excluded by serologic and molecular biological tests. There was no diagnostic evidence for underlying autoimmune or additional metabolic liver disease. Due to a trip to Africa 5 months earlier, the patient was tested for hepatitis E, leading to positive anti-hepatitis E-IgM and negative anti-hepatitis E-IgG. PCR (polymerase chain reaction) detection of hepatitis E virus (HEV) was positive as well. In conclusion, acute HEV infection was diagnosed. After close reconsideration, the nonfitting incubation period precluded a travel-associated infection. Additionally, there was no evidence for current HEV infections within the patient's social environment, so that a zoonotic origin has to be discussed.
Also flagged:immunoglobulinHLAtediumH-2 class Iantibodiesstroke
Journal Article2010-04-01No SnippetsJordan BR.
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This Perspectives article recounts the isolation and sequencing of the first human histocompatibility gene (HLA) in 1980-1981. At the time, general knowledge of the molecules of the immune system was already fairly extensive, and gene rearrangements in the immunoglobulin complex (discovered in 1976) had generated much excitement: HLA was quite obviously the next frontier. The author was able to use a homologous murine H-2 cDNA to identify putative human HLA genomic clones in a lambda-phage library and thus to isolate and sequence the first human histocompatibility gene. This personal account relates the steps that led to this result, describes the highly competitive international environment, and highlights the role of location, connections, and sheer luck in such an achievement. It also puts this work in perspective with a short description of the current knowledge of histocompatibility genes and, finally, presents some reflections on the meaning of "discovery."
…All HTTs lacked BRAF mutations and RET/PTC rearrangements.<h4>Conclusions</h4>Our findings do not support the concept that a high proportion of HTT represents a variant of PTC.…
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<h4>Aims</h4>To compare the expression pattern of five microRNAs (miRNAs) (146b, -181b, -21, -221, -222) of papillary thyroid carcinoma (PTC) and hyalinizing trabecular tumour of the thyroid (HTT).<h4>Methods and results</h4>The expression pattern of five miRNAs known to be up-regulated in PTC was retrospectively analysed in 18 HTTs, adjacent normal thyroid tissue, 10 PTCs, 10 follicular adenomas and 10 non-toxic multinodular goitres (MNG) by reverse transcriptase-polymerase chain reaction using the TaqMan miRNA assay. Furthermore, the two common genetic alterations characteristic for PTC, the V600E mutation of the BRAF gene and RET/PTC 1 and 3 rearrangements, were determined in all HTTs. All miRNAs were significantly up-regulated in PTCs, whereas all miRNAs in HTT, normal thyroid tissue, adenomas, and MNGs were down-regulated. Calculating relative changes in gene expression, a 510-fold change of miRNA 146b between PTC and HTT could be observed followed by fold changes between 6.4 and 29 in the remaining miRNAs (P < 0.001). All HTTs lacked BRAF mutations and RET/PTC rearrangements.<h4>Conclusions</h4>Our findings do not support the concept that a high proportion of HTT represents a variant of PTC. It is suggested that HTTs lacking both a miRNA expression pattern characteristic for PTC and RET/PTC rearrangements are re-designated as 'hyalinizing trabecular adenomas'.
Also flagged:milnacipranfluvoxaminemajor depressive disorderdepressionnorepinephrine transporterNET
Journal Article2010-04-01✓ 4 SnippetsHiguchi H.
In-Text Gene Mentions
Abstract)
…The purpose of this study was to determine whether norepinephrine transporter (NET) gene and serotonin transporter (5-HTT) gene polymorphisms are associated with the antidepressant response to milnacipran, a serotonin and norepinephrine reuptake inhibitor.…
Abstract)
…The results suggest that NET but not 5-HTT polymorphisms in part determine the antidepressant response to milnacipran.…
In a milnacipran study, ninety-six patients with major depressive disorder were treated with milnacipran, 50-100 mg/day, for 6 weeks. Severity of depression was assessed with the Montgomery and Asberg Depression Rating Scale. The purpose of this study was to determine whether norepinephrine transporter (NET) gene and serotonin transporter (5-HTT) gene polymorphisms are associated with the antidepressant response to milnacipran, a serotonin and norepinephrine reuptake inhibitor. Eighty patients completed the study. The presence of the T allele of the NET T-182C polymorphism was associated with a superior antidepressant response. In contrast, no influence of 5-HTTLPR (5-HTT linked polymorphic region) on the antidepressant response to milnacipran was detected. The results suggest that NET but not 5-HTT polymorphisms in part determine the antidepressant response to milnacipran. In a fluvoxamine study, sixty-six patients with major depressive disorder were treated with fluvoxamine, 100-200 mg/day, for 6 weeks. The authors investigated whether 5-HTTLPR was associated with the antidepressant response to fluvoxamine, a selective serotonin reuptake inhibitor. Fifty-seven patients completed the study. The short (s) allele frequency was significantly higher in the responsive individuals than in the nonresponsive ones. The results suggest that fluvoxamine is not less effective in depressive patients carrying the s allele than in those carrying the long (1) allele and it is not less effective in Japanese than in Caucasians.
Also flagged:Hyperferritinaemia-cataract syndromehereditary hyperferritinaemia-cataract syndromeHHCSironcataractL-ferritin
Journal Article2010-04-01✓ 1 SnippetMillonig G, Muckenthaler MU, Mueller S.
In-Text Gene Mentions
S I O 001029)
…An impaired interaction of TfR1 and/or TfR2 with a mutated human haemochromatosis (HFE) protein causes the most common monogenic hereditary disease in humans (hereditary haemochromatosis), which eventually leads to iron overload and tissue damage in several organs[4,5].…
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The hereditary hyperferritinaemia-cataract syndrome (HHCS) is characterised by an autosomal dominant cataract and high levels of serum ferritin without iron overload. The cataract develops due to L-ferritin deposits in the lens and its pulverulent aspect is pathognomonic. The syndrome is caused by mutations within the iron-responsive element of L-ferritin. These mutations prevent efficient binding of iron regulatory proteins 1 and 2 to the IRE in L-ferritin mRNA, resulting in an unleashed ferritin translation. This paper reviews all 31 mutations (27 single nucleotide transitions and four deletions) that have been described since 1995. Laboratory test showing hyperferritinaemia, normal serum iron and normal transferrin saturation are indicative for HHCS after exclusion of other causes of increased ferritin levels (inflammation, malignancy, alcoholic liver disease) and should prompt an ophthalmological consultation for diagnostic confirmation. Invasive diagnostics such as liver biopsy are not indicated. HHCS is an important differential diagnosis of hyperferritinaemia. Haematologists, gastroenterologists and ophthalmologists should be aware of this syndrome to spare patients from further invasive diagnosis (liver biopsy), and also from a false diagnosis of hereditary haemochromatosis followed by venesections. Patients diagnosed with HHCS should be counselled regarding the relative harmlessness of this genetic disease, with early cataract surgery as the only clinical consequence.
Also flagged:Primary tumors of the liverregulation of gene expressioncancerhepatocellular carcinomacholangiocarcinomahepatobiliary cancers
Journal Article2010-04-01No SnippetsHamilton JP.
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Primary tumors of the liver and biliary tree are increasing in frequency and portend a miserable prognosis. Epigenetic regulation of gene expression has emerged as a fundamental aspect of cancer development and progression. The molecular mechanisms of carcinogenesis in hepatocellular carcinoma and cholangiocarcinoma involve a complex interplay of both genetic and epigenetic factors. Recent studies investigating the possible epigenetic mechanisms induced in the disease have shed new light on the molecular underpinnings of hepatobiliary cancers. In addition, epigenetic modifications of DNA in cancer and precancerous lesions offer hope and the promise of novel biomarkers for early cancer detection, prediction, prognosis and response to treatment. Furthermore, the reversal of epigenetic changes represents a potential target for novel therapeutic strategies and medication design.
Fluorophore excited state lifetime is a useful indicator of micro-environment in cellular optical molecular imaging. For quantitative sensing, precise lifetime determination is important, yet is often difficult to accomplish when using the experimental conditions favored by live cells. Here we report the first application of temporal optimization and spatial denoising methods to two-photon time-correlated single photon counting (TCSPC) fluorescence lifetime imaging microscopy (FLIM) to improve lifetime precision in live-cell images. The results demonstrated a greater than five-fold improvement in lifetime precision. This approach minimizes the adverse effects of excitation light on live cells and should benefit FLIM applications to high content analysis and bioimage informatics.
Also flagged:VEGFVascular endothelial growth factorVEGFAblood vesselneurogenesisneurite
Journal Article2010-04-01No SnippetsRosenstein JM, Krum JM, Ruhrberg C.
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Vascular endothelial growth factor (VEGF, VEGFA) is critical for blood vessel growth in the developing and adult nervous system of vertebrates. Several recent studies demonstrate that VEGF also promotes neurogenesis, neuronal patterning, neuroprotection and glial growth. For example, VEGF treatment of cultured neurons enhances survival and neurite growth independently of blood vessels. Moreover, evidence is emerging that VEGF guides neuronal migration in the embryonic brain and supports axonal and arterial co-patterning in the developing skin. Even though further work is needed to understand the various roles of VEGF in the nervous system and to distinguish direct neuronal effects from indirect, vessel-mediated effects, VEGF can be considered a promising tool to promote neuronal health and nerve repair.
Also flagged:Hyalinizing trabecular tumorpapillary carcinomathyroidthyroid neoplasmmedullary carcinomatumor of
Journal Article2010-04-01No SnippetsGupta S, Modi S, Gupta V, Marwah N.
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Hyalinizing trabecular tumor (HTT) is an unusual and controversial lesion of the thyroid gland. Some have considered it a unique entity, some have considered it a variant of papillary carcinoma, and still others have considered it a nonspecific pattern that may be seen with a variety of thyroid lesions. The histological and ultrastructural characteristics of this thyroid neoplasm are well documented; however, its cytological diagnosis by fine needle aspiration cytology (FNAC) remains challenging. The cytomorphological features of this entity overlap with both papillary and medullary carcinoma to a varying extent. We report a case of HTT with cytological evaluation by FNAC in a 28-year-old male.
Journal Article2010-04-01✓ 4 SnippetsLinkowska K, Daca P, Sykutera M, Pufal E, Bloch-Bogusławska E, Grzybowski T.
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…between suicide and5-HTT, MAOA and DAT…
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…polymorphic forms of5-HTT, MAOA or DAT…
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…functional alleles in5-HTT, MAOA and DAT…
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…Functional polymorphisms in5-HTT, MAOA and DAT…
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A better understanding of genetic determinants of suicidal behavior might be very useful in clinical practice. The objectives of the present study were to answer the question whether there is an association between functional polymorphic forms of 5-HTT, MAOA or DAT and suicidality, and to examine whether the combination of functional alleles in 5-HTT, MAOA and DAT genes would predict a predisposition to suicidal behavior. Functional polymorphisms in 5-HTT, MAOA and DAT genes were investigated in 66 male suicide completers and 51 male control subjects from the Polish population. There were no significant differences in the allele and genotype frequencies between the case and control group. In the individual genotype tests, examination of the distribution differences of each genotype showed that genotype (3;12-12;S-S;9-10) differed between the suicide victims and control subjects. This genotype existed only in the control sample and appeared with the frequency of 8% (p = 0.03).
Also flagged:prostate cancerprostate-specific antigenPSAprostatitisbenign prostatic hyperplasiaprostate diseases
Journal Article2010-04-01No SnippetsMochtar CA, Andika RS.
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One of the most important diagnostic tools used to detect prostate cancer is prostate-specific antigen (PSA), yet increased PSA alone does not reflect the presence of prostate cancer. Other pathological prostatic conditions such as prostatitis and benign prostatic hyperplasia (BPH) may also increase the level of PSA. However, unlike in other prostate diseases, PSA has a key role in the diagnosis and management of prostate cancer. The incidence of prostate cancer varies from country to country, with the highest incidence being found in the Western world and the lowest in Asian countries. Owing to the low incidence of prostate cancer, there could be different views regarding the use of PSA in Asian countries, especially for the early detection/screening of prostate cancer. The purpose of this article is to review the use and value of PSA in the diagnosis of prostate diseases (especially prostate cancer) in Asian countries/populations. A literature search was performed in 'MEDLINE' (PubMed) and Google Scholar using main keywords such as 'PSA', 'PSA usage', 'PSA sensitivity and specificity', 'Asia', and various countries in Asia. Articles that provide population/community-based PSA data, together with the characteristics, distribution, and indications for PSA testing in the respective countries, were selected. Eleven papers were finally selected for inclusion in this review. Five studies found that PSA, by its 95th percentile value, have an age-referenced tendency in Asian males, similarly to the West. The predictive values of PSA in detecting prostate cancer are also quite similar to those in Western countries. With the exponential growth of the aging population in the world, especially in Asia, the incidence of prostate cancer will follow this upward trend. Therefore, PSA testing for screening or diagnostic purposes would increase with time in Asia.
…In case of HD, themain reason is the expression of a mutant form of the huntingtin (Htt)protein.…
Introduction)
…the huntingtin (Htt) gene […
Introduction)
…the mutant proteinHttexp experiences a…
Introduction)
…the effect ofHttexp on Ca…
Introduction)
…has established thatHttexp directly and…
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Neurodegenerative disorders, such as Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), Huntington's disease (HD), and spinocerebellar ataxias (SCA) are very important both for fundamental science and for practical medicine. Despite extensive research into the causes of these diseases, clinical researchers have had very limited progress and, as of now, there is still no cure for any of these diseases. One of the main obstacles in the way of creating treatments for these disorders is the fact that their etiology and pathophysiology still remain unclear. This paper reviews results that support the so-called "calcium hypothesis of neurodegenerative diseases." The calcium hypothesis states that the atrophic and degenerative processes in the neurons of AD, PD, ALS, HD, and SCA patients are accompanied by alterations in calcium homeostasis. Moreover, the calcium hypothesis states that this deregulation of calcium signaling is one of the early-stage and key processes in the pathogenesis of these diseases. Based on the results we reviewed, we conclude that the calcium channels and other proteins involved in the neuronal calcium signaling system are potential drug targets for AD, PD, ALS, HD, and SCA therapy.