Also flagged:Drug abuseaddictive disordersaddictionadrenoreceptornicotinecannabinoid
Journal Article2011-12-30No SnippetsKlee EW, Schneider H, Clark KJ, Cousin MA, Ebbert JO, Hooten WM, Karpyak VM, Warner DO, Ekker SC.
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Drug abuse and dependence are multifaceted disorders with complex genetic underpinnings. Identifying specific genetic correlates is challenging and may be more readily accomplished by defining endophenotypes specific for addictive disorders. Symptoms and syndromes, including acute drug response, consumption, preference, and withdrawal, are potential endophenotypes characterizing addiction that have been investigated using model organisms. We present a review of major genes involved in serotonergic, dopaminergic, GABAergic, and adrenoreceptor signaling that are considered to be directly involved in nicotine, opioid, cannabinoid, and ethanol use and dependence. The zebrafish genome encodes likely homologs of the vast majority of these loci. We also review the known expression patterns of these genes in zebrafish. The information presented in this review provides support for the use of zebrafish as a viable model for studying genetic factors related to drug addiction. Expansion of investigations into drug response using model organisms holds the potential to advance our understanding of drug response and addiction in humans.
Also flagged:Tardive dyskinesiahaloperidolchewinggene expressionDrd2Zic4
Journal Article2011-12-30✓ 1 SnippetCrowley JJ, Kim Y, Szatkiewicz JP, Pratt AL, Quackenbush CR, Adkins DE, van den Oord E, Bogue MA, Yang H, Wang W, Threadgill DW, de Villena FP, McLeod HL, Sullivan PF.
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Tardive dyskinesia (TD) is a debilitating, unpredictable, and often irreversible side effect resulting from chronic treatment with typical antipsychotic agents such as haloperidol. TD is characterized by repetitive, involuntary, purposeless movements primarily of the orofacial region. In order to investigate genetic susceptibility to TD, we used a validated mouse model for a systems genetics analysis geared toward detecting genetic predictors of TD in human patients. Phenotypic data from 27 inbred strains chronically treated with haloperidol and phenotyped for vacuous chewing movements were subject to a comprehensive genomic analysis involving 426,493 SNPs, 4,047 CNVs, brain gene expression, along with gene network and bioinformatic analysis. Our results identified ~50 genes that we expect to have high prior probabilities for association with haloperidol-induced TD, most of which have never been tested for association with human TD. Among our top candidates were genes regulating the development of brain motor control regions (Zic4 and Nkx6-1), glutamate receptors (Grin1 and Grin2a), and an indirect target of haloperidol (Drd1a) that has not been studied as well as the direct target, Drd2.
Also flagged:peroxisome proliferator-activated receptor gammainsulininsulin resistanceobesityageingPPARγ2
Journal Article2011-12-30✓ 1 SnippetVivas Y, Martínez-García C, Izquierdo A, Garcia-Garcia F, Callejas S, Velasco I, Campbell M, Ros M, Dopazo A, Dopazo J, Vidal-Puig A, Medina-Gomez G.
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…we identified increasedNEGR1expression in our…
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<h4>Background</h4>The progression towards type 2 diabetes depends on the allostatic response of pancreatic beta cells to synthesise and secrete enough insulin to compensate for insulin resistance. The endocrine pancreas is a plastic tissue able to expand or regress in response to the requirements imposed by physiological and pathophysiological states associated to insulin resistance such as pregnancy, obesity or ageing, but the mechanisms mediating beta cell mass expansion in these scenarios are not well defined. We have recently shown that ob/ob mice with genetic ablation of PPARγ2, a mouse model known as the POKO mouse failed to expand its beta cell mass. This phenotype contrasted with the appropriate expansion of the beta cell mass observed in their obese littermate ob/ob mice. Thus, comparison of these models islets particularly at early ages could provide some new insights on early PPARγ dependent transcriptional responses involved in the process of beta cell mass expansion<h4>Results</h4>Here we have investigated PPARγ dependent transcriptional responses occurring during the early stages of beta cell adaptation to insulin resistance in wild type, ob/ob, PPARγ2 KO and POKO mice. We have identified genes known to regulate both the rate of proliferation and the survival signals of beta cells. Moreover we have also identified new pathways induced in ob/ob islets that remained unchanged in POKO islets, suggesting an important role for PPARγ in maintenance/activation of mechanisms essential for the continued function of the beta cell.<h4>Conclusions</h4>Our data suggest that the expansion of beta cell mass observed in ob/ob islets is associated with the activation of an immune response that fails to occur in POKO islets. We have also indentified other PPARγ dependent differentially regulated pathways including cholesterol biosynthesis, apoptosis through TGF-β signaling and decreased oxidative phosphorylation.
Also flagged:BDNFdepressionbreast cancerserotonin transporterbrain-derived neurotrophic factormedical
Journal Article2011-12-30✓ 5 SnippetsKim JM, Kim SW, Stewart R, Kim SY, Shin IS, Park MH, Yoon JH, Lee JS, Park SW, Kim YH, Yoon JS.
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Abstract)
…This study aimed to investigate whether polymorphisms of interest in 5-HTT, 5-HTR2a, and BDNF genes are associated with depression after mastectomy for breast cancer.…
Abstract)
…This study aimed to investigate whether polymorphisms of interest in 5-HTT, 5-HTR2a, and BDNF genes are associated with …
Abstract)
…No associations with 5-HTT and 5-HTR2a genes (all p values > .21) were found, and no significant gene-gene interactions were identified (all p values > .36).<h4>Conclusions</h4>Our findings support a role of BDNF, not serotonin, in the etiology of depression occurring in women with breast cancer who received a mastectomy.…
Abstract)
…of serotonin transporter (5-HTT) and brain-derived neurotroph…
Abstract)
…of interest in5-HTT, 5-HTR2a, and BDNF…
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<h4>Objective</h4>Polymorphisms of serotonin transporter (5-HTT) and brain-derived neurotrophic factor (BDNF) genes have been investigated as candidate genes for depression occurring in medical disorders. The serotonin 2a receptor (5-HTR2a) genes have been investigated as risk factors for depression but rarely in combination with medical conditions. This study aimed to investigate whether polymorphisms of interest in 5-HTT, 5-HTR2a, and BDNF genes are associated with depression after mastectomy for breast cancer.<h4>Methods</h4>A total of 309 patients with breast cancer were evaluated 1 week after mastectomy, and 244 patients (79%) were followed up 1 year later. Depression (major and minor depressive disorders) was diagnosed according to DSM-IV criteria using the Mini-International Neuropsychiatric Interview and was classified into prevalent, persistent, and incident depression. Individual associations with 5-HTT gene-linked promoter region, serotonin transporter intron 2 variable number tandem repeat, 5-HTR2a 1438A/G, 5-HTR2a 102T/C, and BDNF Val66Met polymorphisms were estimated using logistic regression models, and gene-gene interactions were investigated using the generalized multifactor dimensionality reduction method.<h4>Results</h4>At baseline, 74 patients (24%) were classified with prevalent depression, and at follow-up, 19 patients (8%) and 25 patients (10%) were classified with persistent and incident depression, respectively. The BDNF Met/Met genotype was independently associated with prevalent (odds ratio = 2.63, 95% confidence interval = 1.12-6.14) and persistent (odds ratio = 8.07, 95% confidence interval = 1.26-51.6) depression. No associations with 5-HTT and 5-HTR2a genes (all p values > .21) were found, and no significant gene-gene interactions were identified (all p values > .36).<h4>Conclusions</h4>Our findings support a role of BDNF, not serotonin, in the etiology of depression occurring in women with breast cancer who received a mastectomy.
Also flagged:Left Ventricular Diastolic DysfunctionType 2 DiabetesNonalcoholic Fatty Liver DiseaseSAChypertensionsteatosis
Journal Article2011-12-30✓ 1 SnippetBonapace S, Perseghin G, Molon G, Canali G, Bertolini L, Zoppini G, Barbieri E, Targher G.
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Methods)
…drug-induced liver disease,hemochromatosis, or autoimmune or…
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<h4>Objective</h4>Data on cardiac function in patients with nonalcoholic fatty liver disease (NAFLD) are limited and conflicting. We assessed whether NAFLD is associated with abnormalities in cardiac function in patients with type 2 diabetes.<h4>Research design and methods</h4>We studied 50 consecutive type 2 diabetic individuals without a history of ischemic heart disease, hepatic diseases, or excessive alcohol consumption, in whom NAFLD was diagnosed by ultrasonography. A tissue Doppler echocardiography with myocardial strain measurement was performed in all patients.<h4>Results</h4>Thirty-two patients (64%) had NAFLD, and when compared with the other 18 patients, age, sex, BMI, waist circumference, hypertension, smoking, diabetes duration, microvascular complication status, and medication use were not significantly different. In addition, the left ventricular (LV) mass and volumes, ejection fraction, systemic vascular resistance, arterial elasticity, and compliance were also not different. NAFLD patients had lower e' (8.2 ± 1.5 vs. 9.9 ± 1.9 cm/s, P < 0.005) tissue velocity, higher E-to-e' ratio (7.90 ± 1.3 vs. 5.59 ± 1.1, P < 0.0001), a higher time constant of isovolumic relaxation (43.1 ± 10.1 vs. 33.2 ± 12.9 ms, P < 0.01), higher LV-end diastolic pressure (EDP) (16.5 ± 1.1 vs. 15.1 ± 1.0 mmHg, P < 0.0001), and higher LV EDP/end diastolic volume (0.20 ± 0.03 vs. 0.18 ± 0.02 mmHg, P < 0.05) than those without steatosis. Among the measurements of LV global longitudinal strain and strain rate, those with NAFLD also had higher E/global longitudinal diastolic strain rate during the early phase of diastole (E/SR(E)). All of these differences remained significant after adjustment for hypertension and other cardiometabolic risk factors.<h4>Conclusions</h4>Our data show that in patients with type 2 diabetes and NAFLD, even if the LV morphology and systolic function are preserved, early features of LV diastolic dysfunction may be detected.
Also flagged:Gene expressionacute lymphoblastic leukemiaALLFLT3IRX2TACC2
Journal Article2011-12-30✓ 2 SnippetsKang H, Wilson CS, Harvey RC, Chen IM, Murphy MH, Atlas SR, Bedrick EJ, Devidas M, Carroll AJ, Robinson BW, Stam RW, Valsecchi MG, Pieters R, Heerema NA, Hilden JM, Felix CA, Reaman GH, Camitta B, Winick N, Carroll WL, Dreyer ZE, Hunger SP, Willman CL.
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Abstract)
…elevated expression ofNEGR1was associated with…
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…NEGR1…
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Gene expression profiling was performed on 97 cases of infant ALL from Children's Oncology Group Trial P9407. Statistical modeling of an outcome predictor revealed 3 genes highly predictive of event-free survival (EFS), beyond age and MLL status: FLT3, IRX2, and TACC2. Low FLT3 expression was found in a group of infants with excellent outcome (n = 11; 5-year EFS of 100%), whereas differential expression of IRX2 and TACC2 partitioned the remaining infants into 2 groups with significantly different survivals (5-year EFS of 16% vs 64%; P < .001). When infants with MLL-AFF1 were analyzed separately, a 7-gene classifier was developed that split them into 2 distinct groups with significantly different outcomes (5-year EFS of 20% vs 65%; P < .001). In this classifier, elevated expression of NEGR1 was associated with better EFS, whereas IRX2, EPS8, and TPD52 expression were correlated with worse outcome. This classifier also predicted EFS in an independent infant ALL cohort from the Interfant-99 trial. When evaluating expression profiles as a continuous variable relative to patient age, we further identified striking differences in profiles in infants less than or equal to 90 days of age and those more than 90 days of age. These age-related patterns suggest different mechanisms of leukemogenesis and may underlie the differential outcomes historically seen in these age groups.
Also flagged:gene expressionbindingtumorShprhNrltranslational initiation
Journal Article2011-12-30✓ 1 SnippetSchneider S, Smith T, Hansen U.
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…ForMllt10, there are two…
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Many platforms for genome-wide analysis of gene expression contain 'redundant' measures for the same gene. For example, the most highly utilized platforms for gene expression microarrays, Affymetrix GeneChip® arrays, have as many as ten or more probe sets for some genes. Occasionally, individual probe sets for the same gene report different trends in expression across experimental conditions, a situation that must be resolved in order to accurately interpret the data. We developed an algorithm, SCOREM, for determining the level of agreement between such probe sets, utilizing a statistical test of concordance, Kendall's W coefficient of concordance, and a graph-searching algorithm for the identification of concordant probe sets. We also present methods for consolidating concordant groups into a single value for its corresponding gene and for post hoc analysis of discordant groups. By combining statistical consolidation with sequence analysis, SCOREM possesses the unique ability to identify biologically meaningful discordant behaviors, including differing behaviors in alternate RNA isoforms and tissue-specific patterns of expression. When consolidating concordant behaviors, SCOREM outperforms other methods in detecting both differential expression and overrepresented functional categories.
Also flagged:AtropineCav2.3 R-type Ca²⁺theta oscillationsbehavioralUrethanesignal transduction
Journal Article2011-12-30No SnippetsMüller R, Struck H, Ho MS, Brockhaus-Dumke A, Klosterkötter J, Broich K, Hescheler J, Schneider T, Weiergräber M.
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Hippocampal theta oscillations are key elements in numerous behavioral and cognitive processes. Based on the dualistic theory of theta oscillations, one can differentiate between atropine-sensitive and atropine-insensitive theta subtypes. Urethane-induced atropine-sensitive theta oscillations are driven by muscarinic signal transduction pathways through G protein q/11 alpha subunit (Gα(q/11)), phospholipase β( ¼) (PLCβ( ¼), inositol trisphosphate (InsP₃), diacylglycerole (DAG), and protein kinase C (PKC). Recent findings illustrate that Ca(v)2.3 Ca²⁺ channels are important targets of muscarinic signaling in the hippocampus mediating plateau potential generation, epileptiform burst activity, and complex rhythm generation in the septohippocampal network. To investigate the physiological implications of Ca(v)2.3 Ca²⁺ channels in hippocampal theta oscillations we performed radiotelemetric intrahippocampal (cornu ammonis (CA1)) recordings in urethane (800 mg/kg, i.p.) and atropine (50 mg/kg, i.p.) treated Ca(v)2.3⁺/⁺ and Ca(v)2.3⁻/⁻ mice followed by wavelet analysis of EEG data. Our results demonstrate that Ca(v)2.3 ablation, unlike PLCβ₁ deletion, does not result in complete abolishment of urethane-induced theta oscillations and that both mean and total theta duration is not significantly inhibited by subsequent atropine treatment, indicating that Ca(v)2.3 Ca²⁺ channels are important mediators of atropine-sensitive theta. Although theta frequency remained unchanged between both genotypes, the temporal characteristics of theta distribution, that is, theta architecture were significantly affected by the loss of Ca(v)2.3 Ca²⁺ channels. Our data suggest, for the first time, that Ca(v)2.3 voltage-gated Ca²⁺ channels (VGCC) are an important factor in septohippocampal synchronization associated with theta oscillation.
Journal Article2011-12-29✓ 1 SnippetLi Y, de Magalhães JP.
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The genetic basis of the large species differences in longevity and aging remains a mystery. Thanks to recent large-scale genome sequencing efforts, the genomes of multiple species have been sequenced and can be used for cross-species comparisons to study species divergence in longevity. By analyzing proteins under accelerated evolution in several mammalian lineages where maximum lifespan increased, we identified genes and processes that are candidate targets of selection when longevity evolves. We identified several proteins with longevity-specific selection patterns, including COL3A1 that has previously been related to aging and proteins related to DNA damage repair and response such as DDB1 and CAPNS1. Moreover, we found that processes such as lipid metabolism and cholesterol catabolism show such patterns of selection and suggest a link between the evolution of lipid metabolism, cholesterol catabolism, and the evolution of longevity. Lastly, we found evidence that the proteasome-ubiquitin system is under selection specific to lineages where longevity increased and suggest that its selection had a role in the evolution of longevity. These results provide evidence that natural selection acts on species when longevity evolves, give insights into adaptive genetic changes associated with the evolution of longevity in mammals, and provide evidence that at least some repair systems are selected for when longevity increases.
<h4>Background and objective</h4>Progression of a colorectal adenoma to invasive cancer occurs in a minority of adenomas and is the most crucial step in colorectal cancer pathogenesis. In the majority of cases, this is associated with gain of a substantial part of chromosome 20q, indicating that multiple genes on the 20q amplicon may drive carcinogenesis. The aim of this study was to identify genes located on the 20q amplicon that promote progression of colorectal adenoma to carcinoma.<h4>Design</h4>Functional assays were performed for 32 candidate driver genes for which a positive correlation between 20q DNA copy number and mRNA expression had been demonstrated. Effects of gene knockdown on cell viability, anchorage-independent growth, and invasion were analysed in colorectal cancer cell lines with 20q gain. Colorectal tumour protein expression was examined by immunohistochemical staining of tissue microarrays.<h4>Results</h4>TPX2, AURKA, CSE1L, DIDO1, HM13, TCFL5, SLC17A9, RBM39 and PRPF6 affected cell viability and/or anchorage-independent growth. Chromosome 20q DNA copy number status correlated significantly with TPX2 and AURKA protein levels in a series of colorectal adenomas and carcinomas. Moreover, downmodulation of TPX2 and AURKA was shown to inhibit invasion.<h4>Conclusion</h4>These data identify TPX2 (20q11) and AURKA (20q13.2) as two genes located on distinct regions of chromosome 20q that promote 20q amplicon-driven progression of colorectal adenoma to carcinoma. Therefore the selection advantage imposed by 20q gain in tumour progression is achieved by gain-of-function of multiple cancer-related genes-knowledge that can be translated into novel tests for early diagnosis of progressive adenomas.
Also flagged:DUX4Facioscapulohumeral dystrophyFSHDmuscular dystrophiesstem cell developmenttranscription factor
Journal Article2011-12-29No SnippetsGeng LN, Yao Z, Snider L, Fong AP, Cech JN, Young JM, van der Maarel SM, Ruzzo WL, Gentleman RC, Tawil R, Tapscott SJ.
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Facioscapulohumeral dystrophy (FSHD) is one of the most common inherited muscular dystrophies. The causative gene remains controversial and the mechanism of pathophysiology unknown. Here we identify genes associated with germline and early stem cell development as targets of the DUX4 transcription factor, a leading candidate gene for FSHD. The genes regulated by DUX4 are reliably detected in FSHD muscle but not in controls, providing direct support for the model that misexpression of DUX4 is a causal factor for FSHD. Additionally, we show that DUX4 binds and activates LTR elements from a class of MaLR endogenous primate retrotransposons and suppresses the innate immune response to viral infection, at least in part through the activation of DEFB103, a human defensin that can inhibit muscle differentiation. These findings suggest specific mechanisms of FSHD pathology and identify candidate biomarkers for disease diagnosis and progression.
Journal Article2011-12-29✓ 5 SnippetsWang Y, Gurrin LC, Wluka AE, Bertalli NA, Osborne NJ, Delatycki MB, Giles GG, English DR, Hopper JL, Simpson JA, Graves S, Allen KJ, Cicuttini FM.
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…HFE C282Y homozygosity was associated with an increased risk of both single and bilateral total hip replacement for osteoarthritis.…
Title)
…HFE C282Y homozygosity is associated with an increased risk of total hip replacement for osteoarthritis.…
Abstract)
…The evidence for an association between mutations in the HFE (hemochromatosis) gene and the risk of hip or knee osteoarthritis is inconsistent.…
Abstract)
…<h4>Objective</h4>The evidence for an association between mutations in the HFE (hemochromatosis) gene and the risk of hip or knee osteoarthritis is inconsistent.…
Title)
…HFEC282Y homozygosity is…
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<h4>Objective</h4>The evidence for an association between mutations in the HFE (hemochromatosis) gene and the risk of hip or knee osteoarthritis is inconsistent. Total joint replacement is considered a surrogate measure for symptomatic end-stage osteoarthritis. We examined the relationship between HFE gene mutations and risk of total hip and knee replacement using a prospective cohort study.<h4>Methods</h4>The Melbourne Collaborative Cohort Study recruited participants between 1990 and 1994. Participants born in Australia, New Zealand, the United Kingdom, or Ireland (n = 27,848) were genotyped for the HFE C282Y mutation. Total hip and knee replacements for osteoarthritis during 2001 to 2009 were ascertained from the Australian Orthopaedic Association National Joint Replacement Registry. Hazard ratios (HR)/odds ratios (OR) and confidence intervals (CI) were obtained from Cox regression or logistic regression.<h4>Results</h4>Compared with those with no C282Y mutation, C282Y homozygotes had an increased risk of single total hip replacement (HR 1.94, 95% CI 1.04-3.62) and bilateral total hip replacement (OR 5.86, 95% CI 2.36-14.57) for osteoarthritis, adjusting for age, sex, body mass index, and educational level. Only 3 C282Y homozygotes had single total knee replacement; the HR was 0.51 (95% CI 0.16-1.57). C282Y/H63D compound heterozygosity was not related to the risk of total hip or knee replacement.<h4>Conclusions</h4>HFE C282Y homozygosity was associated with an increased risk of both single and bilateral total hip replacement for osteoarthritis.
<h4>Background</h4>Iron depletion or deficiency in blood donors frequently results in deferrals for low hemoglobin (Hb), yet blood centers remain reluctant to dispense iron replacement therapy to donors.<h4>Study design and methods</h4>During a 39-month period, 1236 blood donors deferred for a Hb level of less than 12.5 g/dL and 400 nondeferred control donors underwent health history screening and laboratory testing (complete blood counts, iron studies). Iron depletion and deficiency were defined as a ferritin level of 9 to 19 and less than 9 µg/L in females and 18 to 29 and less than 18 µg/L in males. Deferred donors and iron-deficient control donors were given a 60-pack of 325-mg ferrous sulfate tablets and instructed to take one tablet daily. Another 60-pack was dispensed at all subsequent visits.<h4>Results</h4>In the low-Hb group, 30 and 23% of females and 8 and 53% of males had iron depletion or deficiency, respectively, compared with 29 and 10% of females and 18 and 21% of males in the control group. Iron-depleted or -deficient donors taking iron showed normalization of iron-related laboratory parameters, even as they continued to donate. Compliance with oral iron was 68%. Adverse gastrointestinal effects occurred in 21% of donors. The study identified 13 donors with serious medical conditions, including eight with gastrointestinal bleeding. No donors had malignancies or hemochromatosis.<h4>Conclusion</h4>Iron depletion or deficiency was found in 53% of female and 61% of male low-Hb donors and in 39% of female and male control donors. Routine administration of iron replacement therapy is safe and effective and prevents the development of iron depletion and deficiency in blood donors.
<h4>Purpose</h4>To identify the genetic defect in a Chinese family with autosomal dominant inherited ectopia lentis.<h4>Methods</h4>twenty-one family members, including seven patients underwent general physical and fully ophthalmic examinations. Genomic DNA was extracted from leukocytes of venous blood of these individuals in the family. Polymerase chain reaction (PCR) amplification and direct sequencing of all 65 coding exons of the fibrillin-1 gene (FBN1) were analyzed.<h4>Results</h4>Mutation screening in FBN1 identified a T>C transition at nucleotide position c,1759 leading to substitution of Cysteine for Arginine at codon 587 (C587R). This nucleotide substitution was not seen in any unaffected member of the family.<h4>Conclusions</h4>We detected a novel mutation in FBN1. Our result expands the mutation spectrum of FBN1 and help in the study of the molecular pathogenesis of Marfan syndrome and Marfan-related diseases.
Journal Article2011-12-29✓ 1 SnippetSilva MC, Fox S, Beam M, Thakkar H, Amaral MD, Morimoto RI.
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…active transport ofHtt-exon1 along microtubules has…
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A hallmark of diseases of protein conformation and aging is the appearance of protein aggregates associated with cellular toxicity. We posit that the functional properties of the proteostasis network (PN) protect the proteome from misfolding and combat the proteotoxic events leading to cellular pathology. In this study, we have identified new components of the proteostasis network that can suppress aggregation and proteotoxicity, by performing RNA interference (RNAi) genetic screens for multiple unrelated conformationally challenged cytoplasmic proteins expressed in Caenorhabditis elegans. We identified 88 suppressors of polyglutamine (polyQ) aggregation, of which 63 modifiers also suppressed aggregation of mutant SOD1(G93A). Of these, only 23 gene-modifiers suppressed aggregation and restored animal motility, revealing that aggregation and toxicity can be genetically uncoupled. Nine of these modifiers were shown to be effective in restoring the folding and function of multiple endogenous temperature-sensitive (TS) mutant proteins, of which five improved folding in a HSF-1-dependent manner, by inducing cytoplasmic chaperones. This triage screening strategy also identified a novel set of PN regulatory components that, by altering metabolic and RNA processing functions, establish alternate cellular environments not generally dependent on stress response activation and that are broadly protective against misfolded and aggregation-prone proteins.
…In earlier studies, a common European mitochondrial haplogroup, haplogroup T (7028 C>T, 10398 G>A, and 13368 G>A) was associated with neuropathy during treatment in a case-control study from the ACTG 384.104 A follow-on study showed that another variant at complex I, subunit ND2, 4917A>G, which has been associated with neurodegenerative diseases, was associated with ART-associated peripheral neuropathy in the white population.105 Iron is essential for mitochondrial function, and in subjects receiving d4T/ddI in ACTG 384, common polymorphisms in the hemochromatosis gene (HFE) 845 G>A and 187 C>G have also been associated with a decreased risk of peripheral neuropathy.106 Because HFE is linked to the class I HLA-A3 allele, it needs to be ascertained that this effect is not due to linkage disequilibrium.…
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…A promoter polymorphism in the TNF-α gene (TNF-238 A) has been associated with more rapid progression of disease.111,112 Mitochondrial haplogroup H was associated with increased thymidine analog-associated limb lipoatrophy and the HFE 187 C>G with less peripheral lipoatrophy.113,114 In another study, polymorphisms in IL-1β 3954 C>T were also associated with protection against lipoatrophy associated with thymidine analogs.115 In a separate study from ACTG 5005s and 384, an SNP in the resistin gene 7640369 C>T was associated positively with lipoatrophy.116 More recently, in a Thai case-control study, HLA-B*4001 was associated with moderate to severe lipoatrophy, defined by anthropomorphic measurements, questionnaire, and dual-emission x-ray absorptiometry scan, with a negative predictive value of 54%.117 These results would need to be verified.…
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Antiretroviral therapy (ART) has evolved considerably over the last three decades. From the early days of monotherapy with high toxicities and pill burdens, through to larger pill burdens and more potent combination therapies, and finally, from 2005 and beyond where we now have the choice of low pill burdens and once-daily therapies. More convenient and less toxic regimens are also becoming available, even in resource-poor settings. An understanding of the individual variation in response to ART, both efficacy and toxicity, has evolved over this time. The strong association of the major histocompatibility class I allele HLA-B*5701 and abacavir hypersensitivity, and its translation and use in routine HIV clinical practice as a predictive marker with 100% negative predictive value, has been a success story and a notable example of the challenges and triumphs in bringing pharmacogenetics to the clinic. In real clinical practice, however, it is going to be the exception rather than the rule that individual biomarkers will definitively guide patient therapy. The need for individualized approaches to ART has been further increased by the importance of non-AIDS comorbidities in HIV clinical practice. In the future, the ideal utilization of the individualized approach to ART will likely consist of a combined approach using a combination of knowledge of drug, virus, and host (pharmacogenetic and pharmacoecologic [factors in the individual's environment that may be dynamic over time]) information to guide the truly personalized prescription. This review will focus on our knowledge of the pharmacogenetics of the efficacy and toxicity of currently available antiretroviral agents and the current and potential utility of such information and approaches in present and future HIV clinical care.
Also flagged:infectionbrucellosisgene expressionB. melitensis infectionlysosomemitogen-activated protein kinase
Journal Article2011-12-28✓ 1 SnippetWang F, Hu S, Liu W, Qiao Z, Gao Y, Bu Z.
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…(Rps6ka4) and TAO1/2 (Taok3), most such genes…
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Brucella melitensis is an important zoonotic pathogen that causes brucellosis, a disease that affects sheep, cattle and occasionally humans. B. melitensis strain M5-90, a live attenuated vaccine cultured from B. melitensis strain M28, has been used as an effective tool in the control of brucellosis in goats and sheep in China. However, the molecular changes leading to attenuated virulence and pathogenicity in B. melitensis remain poorly understood. In this study we employed the Illumina Genome Analyzer platform to perform genome-wide digital gene expression (DGE) analysis of mouse peritoneal macrophage responses to B. melitensis infection. Many parallel changes in gene expression profiles were observed in M28- and M5-90-infected macrophages, suggesting that they employ similar survival strategies, notably the induction of anti-inflammatory and antiapoptotic factors. Moreover, 1019 differentially expressed macrophage transcripts were identified 4 h after infection with the different B. melitensis strains, and these differential transcripts notably identified genes involved in the lysosome and mitogen-activated protein kinase (MAPK) pathways. Further analysis employed gene ontology (GO) analysis: high-enrichment GOs identified endocytosis, inflammatory, apoptosis, and transport pathways. Path-Net and Signal-Net analysis highlighted the MAPK pathway as the key regulatory pathway. Moreover, the key differentially expressed genes of the significant pathways were apoptosis-related. These findings demonstrate previously unrecognized changes in gene transcription that are associated with B. melitensis infection of macrophages, and the central signaling pathways identified here merit further investigation. Our data provide new insights into the molecular attenuation mechanism of strain M5-90 and will facilitate the generation of new attenuated vaccine strains with enhanced efficacy.
Also flagged:Protein Ccoagulationprotein Sdeficiencythromboembolic disordersThrombophilia
Journal Article2011-12-28No SnippetsAthanasiadis G, Buil A, Souto JC, Borrell M, López S, Martinez-Perez A, Lathrop M, Fontcuberta J, Almasy L, Soria JM.
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The Protein C anticoagulant pathway regulates blood coagulation by preventing the inadequate formation of thrombi. It has two main plasma components: protein C and protein S. Individuals with protein C or protein S deficiency present a dramatically increased incidence of thromboembolic disorders. Here, we present the results of a genome-wide association study (GWAS) for protein C and protein S plasma levels in a set of extended pedigrees from the Genetic Analysis of Idiopathic Thrombophilia (GAIT) Project. A total number of 397 individuals from 21 families were typed for 307,984 SNPs using the Infinium® 317 k Beadchip (Illumina). Protein C and protein S (free, functional and total) plasma levels were determined with biochemical assays for all participants. Association with phenotypes was investigated through variance component analysis. After correcting for multiple testing, two SNPs for protein C plasma levels (rs867186 and rs8119351) and another two for free protein S plasma levels (rs1413885 and rs1570868) remained significant on a genome-wide level, located in and around the PROCR and the DNAJC6 genomic regions respectively. No SNPs were significantly associated with functional or total protein S plasma levels, although rs1413885 from DNAJC6 showed suggestive association with the functional protein S phenotype, possibly indicating that this locus plays an important role in protein S metabolism. Our results provide evidence that PROCR and DNAJC6 might play a role in protein C and free protein S plasma levels in the population studied, warranting further investigation on the role of these loci in the etiology of venous thromboembolism and other thrombotic diseases.
Also flagged:organophosphatechlorpyrifosdiazinoncell cycleorganophosphatescholinesterase
Journal Article2011-12-28No SnippetsSlotkin TA, Seidler FJ.
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Developmental organophosphate exposure reduces the numbers of neural cells, contributing to neurobehavioral deficits. We administered chlorpyrifos or diazinon to newborn rats on postnatal days 1-4, in doses straddling the threshold for barely-detectable cholinesterase inhibition, and evaluated gene expression in the cell cycle and apoptosis pathways on postnatal day 5. Both organophosphates evoked transcriptional changes in 20-25% of the genes in each category; chlorpyrifos and diazinon targeted the same genes, with similar magnitudes of change, as evidenced by high concordance. Furthermore, the same effects were obtained with doses above or below the threshold for cholinesterase inhibition, indicating a mechanism unrelated to anticholinesterase actions. We then evaluated the effects of chlorpyrifos in undifferentiated and differentiating PC12 cells and found even greater targeting of cell cycle and apoptosis genes, affecting up to 40% of all genes in the pathways. Notably, the genes affected in undifferentiated cells were not concordant with those in differentiating cells, pointing to dissimilar outcomes dependent on developmental stage. The in vitro model successfully identified 60-70% of the genes affected by chlorpyrifos in vivo, indicating that the effects are exerted directly on developing neural cells. Our results show that organophosphates target the genes regulating the cell cycle and apoptosis in the developing brain and in neuronotypic cells in culture, with the pattern of vulnerability dependent on the specific stage of development. Equally important, these effects do not reflect actions on cholinesterase and operate at exposures below the threshold for any detectable inhibition of this enzyme.
Also flagged:Huntington's diseaseHDautosomal dominant neurodegenerative disorderglutaminescell proliferationbrain-derived neurotrophic factor
Journal Article2011-12-28No SnippetsCastiglioni V, Onorati M, Rochon C, Cattaneo E.
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Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder caused by an excessive expansion of a CAG trinucleotide repeat in the gene encoding the protein huntingtin, resulting in an elongated stretch of glutamines near the N-terminus of the protein. Here we report the derivation of a collection of 11 induced pluripotent stem (iPS) cell lines generated through somatic reprogramming of fibroblasts obtained from the R6/2 transgenic HD mouse line. We show that CAG expansion has no effect on reprogramming efficiency, cell proliferation rate, brain-derived neurotrophic factor level, or neurogenic potential. However, genes involved in the cholesterol biosynthesis pathway, which is altered in HD, are also affected in HD-iPS cell lines. Furthermore, we found a lysosomal gene upregulation and an increase in lysosome number in HD-iPS cell lines. These observations suggest that iPS cells from HD mice replicate some but not all of the molecular phenotypes typically observed in the disease; additionally, they do not manifest increased cell death propensity either under self-renewal or differentiated conditions. More studies will be necessary to transform a revolutionary technology into a powerful platform for drug screening approaches.
Also flagged:serotonin transporterbindingtransporter
Journal Article2011-12-28✓ 2 SnippetsSchain M, Tóth M, Cselényi Z, Stenkrona P, Halldin C, Farde L, Varrone A.
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Abstract)
…for serotonin transporter (5-HTT) binding in cortical…
Abstract)
…and expressing different5-HTTdensities.…
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<h4>Unlabelled</h4>The High Resolution Research Tomograph (HRRT) is the PET system providing the highest resolution for imaging of the human brain. In this study, the improved quantitative performance of the HRRT was evaluated in comparison with a previously developed lower resolution PET system, the ECAT HR. The radioligand [(11)C]MADAM was chosen for the purpose since it provides a signal for serotonin transporter (5-HTT) binding in cortical and sub-cortical brain regions of different sizes and expressing different 5-HTT densities. A secondary objective was to assess the effect of partial volume effect (PVE) correction on the cross-comparability between the two systems.<h4>Method</h4>Six male control subjects (ages 20-35 yr) were examined twice using the HRRT and the HR system, respectively. Regions of interest (ROIs) included cortical regions (frontal cortex, temporal cortex, insula, anterior cingulate cortex, and hippocampus), sub-cortical regions (caudate, putamen, thalamus, dorsal brainstem and ventral midbrain) and cerebellum. The ROIs were manually delineated on T1-weighted MRI-images and subsequently applied to both HRRT and HR images. Regional binding potential (BP(ND)) values were calculated with the simplified reference tissue model (SRTM) using cerebellum as the reference region. The percent difference in BP(ND) between the systems was calculated for each ROI. In addition, both HRRT and HR data were corrected for PVE using established MRI-based methods described by Meltzer and Müller-Gärtner. The effect of PVE correction (PVEc) on the agreement between the systems was assessed via percent difference calculation and linear regression analysis.<h4>Results</h4>Quantification with SRTM showed that regional BP(ND) values for [(11)C]MADAM were on average 23% higher for the HRRT than those obtained by the HR system. More specifically, BP(ND) measured with HRRT was 31.1±48.1% higher in neocortical/limbic regions and 14.6±20.9% higher in sub-cortical regions. The effect of PVEc varied between regions. After correction according to Müller-Gärtner, the agreement between systems was best in the neocortical/limbic regions (3.7±22.5%). With the exception of the caudate, in which the agreement was improved by approximately 17% using the Meltzer method, the effect of PVEc in sub-cortical regions was less pronounced. Linear regression analysis showed improved correlation between the two systems after PVEc, particularly in the neocortical/limbic regions.<h4>Conclusion</h4>As expected, BP(ND) values measured with the HRRT were higher than those measured with the HR due to higher resolution and recovery. The difference in BP(ND) between the two systems was approximately 30% in the neocortical/limbic regions. PVEc improved the agreement between the systems in particular for the neocortical/limbic regions. In these regions, the best agreement was found after applying Müller-Gärtner's PVEc. The demonstrated agreement provides an opportunity for combining data between the two systems in clinical studies aimed at evaluating receptor/transporter availability in cortical brain regions.
Also flagged:protein tyrosine phosphatase 1Bdiabetesobesitycancersodiumcefsulodine
Journal Article2011-12-27✓ 1 SnippetMiller OJ, El Harrak A, Mangeat T, Baret JC, Frenz L, El Debs B, Mayot E, Samuels ML, Rooney EK, Dieu P, Galvan M, Link DR, Griffiths AD.
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I A O 0000326)
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A critical early step in drug discovery is the screening of a chemical library. Typically, promising compounds are identified in a primary screen and then more fully characterized in a dose-response analysis with 7-10 data points per compound. Here, we describe a robust microfluidic approach that increases the number of data points to approximately 10,000 per compound. The system exploits Taylor-Aris dispersion to create concentration gradients, which are then segmented into picoliter microreactors by droplet-based microfluidics. The large number of data points results in IC(50) values that are highly precise (± 2.40% at 95% confidence) and highly reproducible (CV = 2.45%, n = 16). In addition, the high resolution of the data reveals complex dose-response relationships unambiguously. We used this system to screen a chemical library of 704 compounds against protein tyrosine phosphatase 1B, a diabetes, obesity, and cancer target. We identified a number of novel inhibitors, the most potent being sodium cefsulodine, which has an IC(50) of 27 ± 0.83 μM.
Also flagged:RNA-binding proteinsbindingribonucleosidelocalizationRBPgenetic diseases
Journal Article2011-12-27No SnippetsAscano M, Hafner M, Cekan P, Gerstberger S, Tuschl T.
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All mRNA molecules are subject to some degree of post-transcriptional gene regulation (PTGR) involving sequence-dependent modulation of splicing, cleavage and polyadenylation, editing, transport, stability, and translation. The recent introduction of deep-sequencing technologies enabled the development of new methods for broadly mapping interaction sites between RNA-binding proteins (RBPs) and their RNA target sites. In this article, we review crosslinking and immunoprecipitation (CLIP) methods adapted for large-scale identification of target RNA-binding sites and the respective RNA recognition elements. CLIP methods have the potential to detect hundreds of thousands of binding sites in single experiments although the separation of signal from noise can be challenging. As a consequence, each CLIP method has developed different strategies to distinguish true targets from background. We focus on photoactivatable ribonucleoside-enhanced CLIP, which relies on the intracellular incorporation of photoactivatable ribonucleoside analogs into nascent transcripts, and yields characteristic sequence changes upon crosslinking that facilitate the separation of signal from noise. The precise knowledge of the position and distribution of binding sites across mature and primary mRNA transcripts allows critical insights into cellular localization and regulatory function of the examined RBP. When coupled with other systems-wide approaches measuring transcript and protein abundance, the generation of high-resolution RBP-binding site maps across the transcriptome will broaden our understanding of PTGR and thereby lead to new strategies for therapeutic treatment of genetic diseases perturbing these processes.
Also flagged:chromosomeschromatinbinding proteinsorganizationcell cyclemitosis
Journal Article2011-12-27✓ 1 SnippetZhang Y, Heermann DW.
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…Condensinsand Topoisomerase II…
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We introduce a new polymer model for mitotic chromosomes. The key assumption of the model is the ability of the chromatin fibre to cross-link to itself due to binding proteins. These protein-chromatin interactions are included by a probabilistic and dynamic mechanism. The hypothesis is motivated by the observation of high repulsive forces between ring polymers. We performed computer simulations to validate our model. Our results show that the presence of loops leads to a tight compaction and contributes significantly to the bending rigidity of chromosomes. Moreover, our qualitative prediction of the force elongation behaviour is close to experimental findings. The Dynamic Loop Model presented here indicates that the internal structure of mitotic chromosomes is based on self-organization of the chromatin fibre rather than attachment of chromatin to a protein scaffold. It also shows that the number and size of loops have a strong influence on the mechanical properties. We suggest that changes in the mechanical characteristics of chromosomes in different stages of the cell cycle, for example, can be explained by an altered internal loop structure.
Also flagged:cancermembrane transportersmultidrug resistanceglutathionemetabolismBcr-Abl
Journal Article2011-12-26No SnippetsRosenzweig SA.
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Development of resistance to chemotherapeutic drugs represents a significant hindrance to the effective treatment of cancer patients. The molecular mechanisms responsible have been investigated for over half a century and have revealed the lack of a single cause. Rather, a multitude of mechanisms have been delineated ranging from induction and expression of membrane transporters that pump drugs out of cells (multidrug resistance (MDR) phenotype), changes in the glutathione system and altered metabolism to name a few. Treatment of cancer patients/cancer cells with chemotherapeutic agents and/or molecularly targeted drugs is accompanied by acquisition of resistance to the treatment administered. Chemotherapeutic agent resistance was initially assumed to be due to induction of mutations leading to a resistant phenotype. This has also been true for molecularly targeted drugs. Considerable experience has been gained from the study of agents targeting the Bcr-Abl tyrosine kinase including imatinib, dasatinib and sunitinib. It is clear that mutations alone are not responsible for the many resistance mechanisms in play. Rather, additional mechanisms are involved, ranging from epigenetic changes, alternative splicing and the induction of alternative/compensatory signaling pathways. In this review, resistance to receptor tyrosine kinase inhibitors (RTKIs), RTK-directed antibodies and antibodies that inactivate ligands for RTKs are discussed. New approaches and concepts aimed at avoiding the generation of drug resistance will be examined. The recent observation that many RTKs, including the IGF-1R, are dependence receptors that induce apoptosis in a ligand-independent manner will be discussed and the implications this signaling paradigm has on therapeutic strategies will be considered.
Also flagged:antibodyAPRILIL-21immunoglobulinimmunoglobulinsIg
Journal Article2011-12-25No SnippetsPuga I, Cols M, Barra CM, He B, Cassis L, Gentile M, Comerma L, Chorny A, Shan M, Xu W, Magri G, Knowles DM, Tam W, Chiu A, Bussel JB, Serrano S, Lorente JA, Bellosillo B, Lloreta J, Juanpere N, Alameda F, Baró T, de Heredia CD, Torán N, Català A, Torrebadell M, Fortuny C, Cusí V, Carreras C, Diaz GA, Blander JM, Farber CM, Silvestri G, Cunningham-Rundles C, Calvillo M, Dufour C, Notarangelo LD, Lougaris V, Plebani A, Casanova JL, Ganal SC, Diefenbach A, Aróstegui JI, Juan M, Yagüe J, Mahlaoui N, Donadieu J, Chen K, Cerutti A.
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Neutrophils use immunoglobulins to clear antigen, but their role in immunoglobulin production is unknown. Here we identified neutrophils around the marginal zone (MZ) of the spleen, a B cell area specialized in T cell-independent immunoglobulin responses to circulating antigen. Neutrophils colonized peri-MZ areas after postnatal mucosal colonization by microbes and enhanced their B cell-helper function after receiving reprogramming signals, including interleukin 10 (IL-10), from splenic sinusoidal endothelial cells. Splenic neutrophils induced immunoglobulin class switching, somatic hypermutation and antibody production by activating MZ B cells through a mechanism that involved the cytokines BAFF, APRIL and IL-21. Neutropenic patients had fewer and hypomutated MZ B cells and a lower abundance of preimmune immunoglobulins to T cell-independent antigens, which indicates that neutrophils generate an innate layer of antimicrobial immunoglobulin defense by interacting with MZ B cells.
…As a representative cytosolic model, we examined the effects of the PRs on Huntingtin aggregation in PC12 cells, conditionally expressing human Huntingtin (htt) exon 1 containing an expansion of 74 glutamines, fused to green fluorescent protein (GFP) (httQ74-GFP)32.…
Results)
…expressing human Huntingtin (htt) exon 1 containing…
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Protein homeostasis (proteostasis) is essential for cellular and organismal health. Stress, aging and the chronic expression of misfolded proteins, however, challenge the proteostasis machinery and the vitality of the cell. Enhanced expression of molecular chaperones, regulated by heat shock transcription factor-1 (HSF-1), has been shown to restore proteostasis in a variety of conformational disease models, suggesting this mechanism as a promising therapeutic approach. We describe the results of a screen comprised of ∼900,000 small molecules that identified new classes of small-molecule proteostasis regulators that induce HSF-1-dependent chaperone expression and restore protein folding in multiple conformational disease models. These beneficial effects to proteome stability are mediated by HSF-1, FOXO, Nrf-2 and the chaperone machinery through mechanisms that are distinct from current known small-molecule activators of the heat shock response. We suggest that modulation of the proteostasis network by proteostasis regulators may be a promising therapeutic approach for the treatment of a variety of protein conformational diseases.
Also flagged:prostate cancerPCahereditary prostate cancercomplexcancerdeath
Journal Article2011-12-25No SnippetsJin G, Lu L, Cooney KA, Ray AM, Zuhlke KA, Lange EM, Cannon-Albright LA, Camp NJ, Teerlink CC, Fitzgerald LM, Stanford JL, Wiley KE, Isaacs SD, Walsh PC, Foulkes WD, Giles GG, Hopper JL, Severi G, Eeles R, Easton D, Kote-Jarai Z, Guy M, Rinckleb A, Maier C, Vogel W, Cancel-Tassin G, Egrot C, Cussenot O, Thibodeau SN, McDonnell SK, Schaid DJ, Wiklund F, Grönberg H, Emanuelsson M, Whittemore AS, Oakley-Girvan I, Hsieh CL, Wahlfors T, Tammela T, Schleutker J, Catalona WJ, Zheng SL, Ostrander EA, Isaacs WB, Xu J, International Consortium for Prostate Cancer Genetics.
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Multiple prostate cancer (PCa) risk-related loci have been discovered by genome-wide association studies (GWAS) based on case-control designs. However, GWAS findings may be confounded by population stratification if cases and controls are inadvertently drawn from different genetic backgrounds. In addition, since these loci were identified in cases with predominantly sporadic disease, little is known about their relationships with hereditary prostate cancer (HPC). The association between seventeen reported PCa susceptibility loci was evaluated with a family-based association test using 1,979 hereditary PCa families of European descent collected by members of the International Consortium for Prostate Cancer Genetics, with a total of 5,730 affected men. The risk alleles for 8 of the 17 loci were significantly over-transmitted from parents to affected offspring, including SNPs residing in 8q24 (regions 1, 2 and 3), 10q11, 11q13, 17q12 (region 1), 17q24 and Xp11. In subgroup analyses, three loci, at 8q24 (regions 1 and 2) plus 17q12, were significantly over-transmitted in hereditary PCa families with five or more affected members, while loci at 3p12, 8q24 (region 2), 11q13, 17q12 (region 1), 17q24 and Xp11 were significantly over-transmitted in HPC families with an average age of diagnosis at 65 years or less. Our results indicate that at least a subset of PCa risk-related loci identified by case-control GWAS are also associated with disease risk in HPC families.
Also flagged:hereditary angioedemaC1 inhibitordeficiencyC1-INHEstrogensprogestins
Journal Article2011-12-24✓ 1 SnippetCaballero T, Farkas H, Bouillet L, Bowen T, Gompel A, Fagerberg C, Bjökander J, Bork K, Bygum A, Cicardi M, de Carolis C, Frank M, Gooi JH, Longhurst H, Martínez-Saguer I, Nielsen EW, Obtulowitz K, Perricone R, Prior N, C-1-INH Deficiency Working Group.
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Abstract)
…at the 6thC1 InhibitorInhibitor Deficiency Workshop…
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<h4>Background</h4>There are a limited number of publications on the management of gynecologic/obstetric events in female patients with hereditary angioedema caused by C1 inhibitor deficiency (HAE-C1-INH).<h4>Objective</h4>We sought to elaborate guidelines for optimizing the management of gynecologic/obstetric events in female patients with HAE-C1-INH.<h4>Methods</h4>A roundtable discussion took place at the 6th C1 Inhibitor Deficiency Workshop (May 2009, Budapest, Hungary). A review of related literature in English was performed.<h4>Results</h4>Contraception: Estrogens should be avoided. Barrier methods, intrauterine devices, and progestins can be used. Pregnancy: Attenuated androgens are contraindicated and should be discontinued before attempting conception. Plasma-derived human C1 inhibitor concentrate (pdhC1INH) is preferred for acute treatment, short-term prophylaxis, or long-term prophylaxis. Tranexamic acid or virally inactivated fresh frozen plasma can be used for long-term prophylaxis if human plasma-derived C1-INH is not available. No safety data are available on icatibant, ecallantide, or recombinant human C1-INH (rhC1INH). Parturition: Complications during vaginal delivery are rare. Prophylaxis before labor and delivery might not be clinically indicated, but pdhC1INH therapeutic doses (20 U/kg) should be available. Nevertheless, each case should be treated based on HAE-C1-INH symptoms during pregnancy and previous labors. pdhC1INH prophylaxis is advised before forceps or vacuum extraction or cesarean section. Regional anesthesia is preferred to endotracheal intubation. Breast cancer: Attenuated androgens should be avoided. Antiestrogens can worsen angioedema symptoms. In these cases anastrozole might be an alternative. Other issues addressed include special features of HAE-C1-INH treatment in female patients, genetic counseling, infertility, abortion, lactation, menopause treatment, and endometrial cancer.<h4>Conclusions</h4>A consensus for the management of female patients with HAE-C1-INH is presented.
…Expression of mutant Prdx6 with either peroxidase activity or PLA(2) activity alone each partially rescued the survival of Prdx6 null cells, while constructs with both active sites mutated failed to rescue.…
Abstract)
…Contrary to the general assumption that the peroxidase activity is the main mechanism for Prdx6 antioxidant function, these results indicate that the PLA(2) activity also plays a substantial role in protecting cells against oxidant stress caused by an exogenous hydroperoxide.…
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…each activity inPrdx6-mediated protection of mouse…
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…not further sensitizePrdx6null cells.…
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…Lethality inPrdx6null PMVEC was…
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<h4>Aims</h4>Peroxiredoxin 6 (Prdx6), a bifunctional enzyme with glutathione peroxidase and phospholipase A(2) (PLA(2)) activities, has been demonstrated as playing a critical role in antioxidant defense of the lung. Our aim was to evaluate the relative role of each activity in Prdx6-mediated protection of mouse pulmonary microvascular endothelial cells (PMVECs) against the peroxidative stress of treatment with tert-butyl hydroperoxide (tBOOH).<h4>Results</h4>PMVEC from Prdx6 null mice showed increased lethality on tBOOH exposure (50-200 μM) compared with wild-type (WT) controls. Treatment with 1-hexadecyl-3-trifluoroethylglycero-sn-2-phosphomethanol (MJ33), a Prdx6 PLA(2) activity inhibitor, increased the sensitivity of WT cells to peroxidative stress, but did not further sensitize Prdx6 null cells. Lethality in Prdx6 null PMVEC was "rescued" by transfection with a construct leading to the expression of WT rat Prdx6. Expression of mutant Prdx6 with either peroxidase activity or PLA(2) activity alone each partially rescued the survival of Prdx6 null cells, while constructs with both active sites mutated failed to rescue. Co-transfection with two different constructs, each expressing one activity, rescued cells as well as the WT construct.<h4>Innovation and conclusion</h4>Contrary to the general assumption that the peroxidase activity is the main mechanism for Prdx6 antioxidant function, these results indicate that the PLA(2) activity also plays a substantial role in protecting cells against oxidant stress caused by an exogenous hydroperoxide.
Also flagged:defectsMendelian disordersfibrosisCFTRHuntington diseaseBRCA1
Journal Article2011-12-23No SnippetsBailey-Wilson JE, Wilson AF.
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Linkage analysis was developed to detect excess co-segregation of the putative alleles underlying a phenotype with the alleles at a marker locus in family data. Many different variations of this analysis and corresponding study design have been developed to detect this co-segregation. Linkage studies have been shown to have high power to detect loci that have alleles (or variants) with a large effect size, i.e. alleles that make large contributions to the risk of a disease or to the variation of a quantitative trait. However, alleles with a large effect size tend to be rare in the population. In contrast, association studies are designed to have high power to detect common alleles which tend to have a small effect size for most diseases or traits. Although genome-wide association studies have been successful in detecting many new loci with common alleles of small effect for many complex traits, these common variants often do not explain a large proportion of disease risk or variation of the trait. In the past, linkage studies were successful in detecting regions of the genome that were likely to harbor rare variants with large effect for many simple Mendelian diseases and for many complex traits. However, identifying the actual sequence variant(s) responsible for these linkage signals was challenging because of difficulties in sequencing the large regions implicated by each linkage peak. Current 'next-generation' DNA sequencing techniques have made it economically feasible to sequence all exons or the whole genomes of a reasonably large number of individuals. Studies have shown that rare variants are quite common in the general population, and it is now possible to combine these new DNA sequencing methods with linkage studies to identify rare causal variants with a large effect size. A brief review of linkage methods is presented here with examples of their relevance and usefulness for the interpretation of whole-exome and whole-genome sequence data.
Also flagged:Spasmolytic polypeptidegastric cancerLgr5intrinsicpepsinogentamoxifen
Journal Article2011-12-23✓ 1 SnippetNam KT, O'Neal RL, Coffey RJ, Finke PE, Barker N, Goldenring JR.
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<h4>Objective</h4>Metaplastic lineages in the oxyntic mucosa of the stomach are critical preneoplastic precursors of gastric cancer. Recent studies have demonstrated that spasmolytic polypeptide-expressing metaplasia (SPEM) in the mouse oxyntic mucosa arises from transdifferentiation of mature gastric chief cells. Other investigations of intestinal progenitor cells have shown that cells demonstrating transcriptional activity for leucine-rich repeat containing G-protein-coupled receptor 5 (Lgr5) in the intestine, colon and gastric antrum function as adult stem cells. We have now investigated whether cells demonstrating Lgr5 transcriptional activity in the oxyntic mucosa of mice might be responsible for development of metaplasia.<h4>Design</h4>Lgr5-EGFP-IRES-Cre(ERT2/+);Rosa26R mice were used to examine the distribution of Lgr5 transcriptionally active cells in the normal oxyntic mucosa as well as after treatment with DMP-777 or L-635 to induce acute SPEM. Lineage mapping was performed to determine if Lgr5-expressing cells gave rise to SPEM.<h4>Results</h4>Cells expressing transcriptional activity for Lgr5 in the oxyntic mucosa were present as scattered rare cells only along the lesser curvature of the stomach. These cells also stained for markers of chief cells (intrinsic factor and pepsinogen) but never showed any staining for proliferative markers (Ki-67). In Lgr5-EGFP-IRES-Cre(ERT2/+);Rosa26R mice induced with tamoxifen, treatment with either DMP-777 or L-635 to induce acute oxyntic atrophy caused induction of SPEM, but no lineage mapping into SPEM from Lgr5-expressing cells was observed.<h4>Conclusion</h4>The results indicate that, while chief cells with Lgr5 transcriptional activity are present along the lesser curvature of the gastric oxyntic mucosa, they are not responsible for production of metaplasia.
Also flagged:chronic liver diseasecirrhosisemphysemaAntitrypsinα1-antitrypsin) deficiency
Journal Article2011-12-23✓ 1 SnippetNelson DR, Teckman J, Di Bisceglie AM, Brenner DA.
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…hemochromatosis…
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Alpha(1)-antitrypsin (A1AT) deficiency is an autosomal codominant disease that can cause chronic liver disease, cirrhosis, and hepatocellular carcinoma in children and adults and increases risk for emphysema in adults. The development of symptomatic disease varies; some patients have life-threatening symptoms in childhood, whereas others remain asymptomatic and healthy into old age. As a result of this variability, patients present across multiple disciplines, including pediatrics, adult medicine, hepatology, genetics, and pulmonology. This can give physicians the mistaken impression that the condition is less common than it actually is and can lead to fragmented care that omits critical interventions commonly performed by other specialists. We sought to present a rational approach for hepatologists to manage adult patients with A1AT deficiency.
Also flagged:cancercancersbreast cancercell cyclechronic lymphocytic leukemiatumor
Journal Article2011-12-23No SnippetsZhang ZJ, Ma SL.
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miRNAs are small, endogenous, non-coding RNAs that negatively regulate protein-coding mRNAs at the post-transcriptional level. It is estimated that in humans thousands of miRNAs are expressed and more than 700 miRNAs have been described to date. About 50% of annotated human miRNAs are detected in regions of fragile sites, which are associated with cancer. The available evidence has shown that miRNAs widely participate in the development or progression of many types of cancers, including breast cancer. The role of miRNAs in breast cancer has been widely investigated; here, we will focus on what is known about the working mechanism of miRNAs in different stages of breast cancer development.
Also flagged:CB1 receptorsHuntington's diseaseCannabinoid CB1 receptorsHDcannabinoid receptorWIN 55,212-2
Journal Article2011-12-23No SnippetsChiodi V, Uchigashima M, Beggiato S, Ferrante A, Armida M, Martire A, Potenza RL, Ferraro L, Tanganelli S, Watanabe M, Domenici MR, Popoli P.
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Cannabinoid CB1 receptors (CB1Rs) are known to be downregulated in patients and in animal models of Huntington's disease (HD). However, the functional meaning of this reduction, if any, is still unclear. Here, the effects of the cannabinoid receptor agonist WIN 55,212-2 (WIN) were investigated on striatal synaptic transmission and on glutamate and GABA release in symptomatic R6/2 mice, a genetic model of HD. The expression levels of CB1Rs in glutamatergic and GABAergic synapses were also evaluated. We found that in R6/2 mice, WIN effects on synaptic transmission and glutamate release were significantly increased with respect to wild type mice. On the contrary, a decrease in WIN-induced reduction of GABA release was found in R6/2 versus WT mice. The expression of CB1Rs in GABAergic neurons was drastically reduced, while CB1Rs levels in glutamatergic neurons were unchanged. These results demonstrate that the expression and functionality of CB1Rs are differentially affected in GABAergic and glutamatergic neurons in R6/2 mice. As a result, the balance between CB1Rs expressed by the two neuronal populations and, thus, the net effect of CB1R stimulation, is profoundly altered in HD mice.
Also flagged:gene expressionchromatinhistoneslocalizationcytoplasmcell nucleus
Journal Article2011-12-23✓ 1 SnippetDa Sacco L, Baldassarre A, Masotti A.
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…Becausechromatin modifiersmodifiers such as…
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The advent of next generation sequencing revealed that a fraction of transcribed RNAs (short and long RNAs) is non-coding. Long non-coding RNAs (lncRNAs) have a crucial role in regulating gene expression and in epigenetics (chromatin and histones remodeling). LncRNAs may have different roles: gene activators (signaling), repressors (decoy), cis and trans gene expression regulators (guides) and chromatin modificators (scaffolds) without the need to be mutually exclusive. LncRNAs are also implicated in a number of diseases. The huge amount of inhomogeneous data produced so far poses several bioinformatics challenges spanning from the simple annotation to the more complex functional annotation. In this review, we report and discuss several bioinformatics resources freely available and dealing with the study of lncRNAs. To our knowledge, this is the first review summarizing all the available bioinformatics resources on lncRNAs appeared in the literature after the completion of the human genome project. Therefore, the aim of this review is to provide a little guide for biologists and bioinformaticians looking for dedicated resources, public repositories and other tools for lncRNAs functional analysis.
The establishment of more efficient approaches for developmental neurotoxicity testing (DNT) has been an emerging issue for children's environmental health. Here we describe a systematic approach for DNT using the neuronal differentiation of mouse embryonic stem cells (mESCs) as a model of fetal programming. During embryoid body (EB) formation, mESCs were exposed to 12 chemicals for 24 h and then global gene expression profiling was performed using whole genome microarray analysis. Gene expression signatures for seven kinds of gene sets related to neuronal development and neuronal diseases were selected for further analysis. At the later stages of neuronal cell differentiation from EBs, neuronal phenotypic parameters were determined using a high-content image analyzer. Bayesian network analysis was then performed based on global gene expression and neuronal phenotypic data to generate comprehensive networks with a linkage between early events and later effects. Furthermore, the probability distribution values for the strength of the linkage between parameters in each network was calculated and then used in principal component analysis. The characterization of chemicals according to their neurotoxic potential reveals that the multi-parametric analysis based on phenotype and gene expression profiling during neuronal differentiation of mESCs can provide a useful tool to monitor fetal programming and to predict developmentally neurotoxic compounds.
Also flagged:type II diabetesmetabolic disorderstype 2 diabetesgene expressionimmune responseslipid
Journal Article2011-12-23No SnippetsMao J, Ai J, Zhou X, Shenwu M, Ong M, Blue M, Washington JT, Wang X, Deng Y.
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<h4>Background</h4>Along with obesity, physical inactivity, and family history of metabolic disorders, African American ethnicity is a risk factor for type 2 diabetes (T2D) in the United States. However, little is known about the differences in gene expression and transcriptomic profiles of blood in T2D between African Americans (AA) and Caucasians (CAU), and microarray analysis of peripheral white blood cells (WBCs) from these two ethnic groups will facilitate our understanding of the underlying molecular mechanism in T2D and identify genetic biomarkers responsible for the disparities.<h4>Results</h4>A whole human genome oligomicroarray of peripheral WBCs was performed on 144 samples obtained from 84 patients with T2D (44 AA and 40 CAU) and 60 healthy controls (28 AA and 32 CAU). The results showed that 30 genes had significant difference in expression between patients and controls (a fold change of <-1.4 or >1.4 with a P value <0.05). These known genes were mainly clustered in three functional categories: immune responses, lipid metabolism, and organismal injury/abnormaly. Transcriptomic analysis also showed that 574 genes were differentially expressed in AA diseased versus AA control, compared to 200 genes in CAU subjects. Pathway study revealed that "Communication between innate and adaptive immune cells"/"Primary immunodeficiency signaling" are significantly down-regulated in AA patients and "Interferon signaling"/"Complement System" are significantly down-regulated in CAU patients.<h4>Conclusions</h4>These newly identified genetic markers in WBCs provide valuable information about the pathophysiology of T2D and can be used for diagnosis and pharmaceutical drug design. Our results also found that AA and CAU patients with T2D express genes and pathways differently.
Also flagged:arachidonic acidphospholipidsallergic diseasesfatty acideicosapentaenoic aciddocosahexaenoic acid
Journal Article2011-12-22✓ 2 SnippetsKakutani S, Ishikura Y, Tateishi N, Horikawa C, Tokuda H, Kontani M, Kawashima H, Sakakibara Y, Kiso Y, Shibata H, Morita I.
In-Text Gene Mentions
Methods)
…(APTT), antithrombin III (ATIII), high-sensitivity C-reactive…
Discussion)
…(PT, APTT andATIII) remained unaltered and…
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<h4>Background</h4>The importance of arachidonic acid (ARA) among the elderly has recently gained increased attention. The effects of ARA supplementation in the elderly are not fully understood, although ARA is considered to be associated with various diseases. We investigate whether ARA supplementation to Japanese elderly subjects affects clinical parameters involved in cardiovascular, inflammatory, and allergic diseases. We also examine the levels of ARA metabolites such as prostanoids during intervention.<h4>Methods</h4>We conducted a randomized, double-blind and placebo-controlled parallel group intervention trial. ARA-enriched oil (240 or 720 mg ARA per day) or placebo was administered to Japanese healthy men and women aged 55-70 years for 4 weeks followed by a 4-week washout period. The fatty acid contents of plasma phospholipids, clinical parameters, and ARA metabolites were determined at baseline, 2, 4, and 8 weeks.<h4>Results</h4>The ARA content in plasma phospholipids in the ARA-administrated groups increased dose-dependently and was almost the same at 2 weeks and at 4 weeks. The elevated ARA content decreased to nearly baseline during a 4-week washout period. During the supplementation and washout periods, no changes were observed in eicosapentaenoic acid and docosahexaenoic acid contents. There were no changes in clinical blood parameters related to cardiovascular, inflammatory and allergic diseases. ARA supplementation did not alter the level of ARA metabolites such as urinary 11-dehydro thromboxane B2, 2,3-dinor-6-keto prostaglandin (PG) F1α and 9,15-dioxo-11α-hydroxy-13,14-dihydro-2,3,4,5-tetranor-prostan-1,20-dioic acid (tetranor-PGEM), and plasma PGE2 and lipoxin A4. ARA in plasma phospholipids was not correlated with ARA metabolite levels in the blood or urine.<h4>Conclusion</h4>These results indicate that ARA supplementation, even at a relatively high dose, does not increase ARA metabolites, and suggest that it does not induce cardiovascular, inflammatory or allergic diseases in Japanese elderly individuals.
…AP (alpl), Deleted in colorectal carcinoma (Dcc), and Itga8 mRNA expression increased in culture (Figure 1e).…
Methods)
…Sox2, CD133, Alpl,Dcc, Bmp4, Sox18 Corin…
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In neonatal mouse skin, two types of dermal papilla (DP) are distinguished by Sox2 expression: CD133+Sox2+ DP are associated with guard/awl/auchene hairs, whereas CD133+Sox2- DP are associated with zigzag (ZZ) hairs. We describe a three-dimensional hydrogel culture system that supports clonal growth of CD133+Sox2+, CD133+Sox2-, and CD133-Sox2- (non-DP) neonatal dermal cells. All three cell populations formed spheres that expressed the DP markers alkaline phosphatase, α8 integrin, and CD133. Nevertheless, spheres formed by CD133- cells did not efficiently support hair follicle formation in skin reconstitution assays. In the presence of freshly isolated P2 dermal cells, CD133+Sox2+ and CD133+Sox2- spheres contributed to the DP of both AA and ZZ hairs. Hair type did not correlate with sphere size. Sox2 expression was maintained in culture, but not induced significantly in Sox2- cells in vitro or in vivo, suggesting that Sox2+ cells are a distinct cellular lineage. Although Sox2+ cells were least efficient at forming spheres, they had the greatest ability to contribute to DP and non-DP dermis in reconstituted skin. As the culture system supports clonal growth of DP cells and maintenance of distinct DP cell types, it will be useful for further analysis of intrinsic and extrinsic signals controlling DP function.
…-1 (PAI-1), antithrombin-III (ATIII), fibrinogen, and white…
Abstract)
…In obese people,ATIII, fibrinogen, and WBC…
Abstract)
…bariatric surgery, theATIIIlevel continued to…
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The objective of this study was to establish the relationship between the plasminogen activator inhibitor-1 (PAI-1), antithrombin-III (ATIII), fibrinogen, and white blood cell (WBC) levels in severely obese patients. We analyzed various plasma parameters implicated in the intrinsic and extrinsic coagulation pathway from 34 severely obese patients before and 1, 6, and 12 months after gastric bypass. In obese people, ATIII, fibrinogen, and WBC levels were in the upper limit of the normal range, and all were higher and significantly different from nonobese people. After bariatric surgery, the ATIII level continued to be high during the first month and increased until 12 months, while fibrinogen decreased only at that time. PAI-1 plasma protein and PAI-1 mRNA levels in liver and adipose tissue show similar profiles and had a strong positive correlation (r = 0.576, P = 0.0003 in liver; r = 0.433, P = 0.0004 in adipose tissue). They were higher in obese patients compared with nonobese control, but tended to recover normal values 1 month after surgery. Thus, the liver and adipose tissue could be an important source of PAI-1 protein in plasma. Gastric bypass surgery leads to a normalization of the hematological profile and a decrease in PAI-1 levels, which entails a decrease of risk for thromboembolism in severely obese.
Also flagged:grkbindingchromatindeathmitochondrialcytoplasmic
Journal Article2011-12-22No SnippetsSerbus LR, Ferreccio A, Zhukova M, McMorris CL, Kiseleva E, Kiseleva E, Sullivan W.
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Although much is known about interactions between bacterial endosymbionts and their hosts, little is known concerning the host factors that influence endosymbiont titer. Wolbachia endosymbionts are globally dispersed throughout most insect species and are the causative agent in filarial nematode-mediated disease. Our investigation indicates that gurken (grk), a host gene encoding a crucial axis determinant, has a cumulative, dosage-sensitive impact on Wolbachia growth and proliferation during Drosophila oogenesis. This effect appears to be mediated by grk mRNA and its protein-binding partners Squid and Hrp48/Hrb27C, implicating the grk mRNA-protein (mRNP) complex as a rate-limiting host factor controlling Wolbachia titer. Furthermore, highly infected flies exhibit defects that match those occurring with disruption of grk mRNPs, such as nurse cell chromatin disruptions and malformation of chorionic appendages. These findings suggest a feedback loop in which Wolbachia interaction with the grk mRNP affects both Wolbachia titer and grk mRNP function.
Also flagged:sulfateinfectionanionsnitratenitrogenasparagine
Journal Article2011-12-22✓ 1 SnippetSong H, Niederweis M.
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…DCC…
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Knowledge of the metabolic pathways used by Mycobacterium tuberculosis during infection is important for understanding its nutrient requirements and host adaptation. However, uptake, the first step in the utilization of nutrients, is poorly understood for many essential nutrients, such as inorganic anions. Here, we show that M. tuberculosis utilizes nitrate as the sole nitrogen source, albeit at lower efficiency than asparagine, glutamate, and arginine. The growth of the porin triple mutant M. smegmatis ML16 in media with limiting amounts of nitrate and sulfate as sole nitrogen and sulfur sources, respectively, was delayed compared to that of the wild-type strain. The uptake of sulfate was 40-fold slower than that of the wild-type strain, indicating that the efficient uptake of these anions is dependent on porins. The uptake by M. tuberculosis of sulfate and phosphate was approximately 40- and 10-fold slower than that of M. smegmatis, respectively, which is consistent with the slower growth of M. tuberculosis. However, the uptake of these anions by M. tuberculosis is orders of magnitude faster than diffusion through lipid membranes, indicating that unknown outer membrane proteins are required to facilitate this process.
Also flagged:VRK1phosphorylationhistone H3mitosiscell cyclinghistone
Journal Article2011-12-22✓ 1 SnippetKim W, Chakraborty G, Kim S, Shin J, Park CH, Jeong MW, Bharatham N, Yoon HS, Kim KT.
In-Text Gene Mentions
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…VRK2…
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VRK1-mediated phosphorylation of histone H3 should be restricted in mitosis for consistent cell cycling, and defects in this process trigger cellular catastrophe. However, an interphasic regulator against VRK1 has not been actually investigated so far. Here, we show that the histone variant macrodomain-containing histone H2A1.2 functions as a suppressor against VRK1 during interphase. The level of macroH2A1.2 was markedly reduced in the mitotic phase, and the macroH2A1.2-mediated inhibition of histone H3 phosphorylation occurred mainly during interphase. We also found direct interaction and binding features between VRK1 and macroH2A1.2 by NMR spectroscopy. Hence, our findings might provide valuable insight into the underlying molecular mechanism regarding an epigenetic regulation of histone H3 during the cell cycle.
Also flagged:cardiac arrhythmiashereditary hemochromatosisironHHcardiovascular diseasesupraventricular ectopy
Journal Article2011-12-22✓ 4 SnippetsShizukuda Y, Tripodi DJ, Zalos G, Bolan CD, Yau YY, Leitman SF, Waclawiw MA, Rosing DR.
In-Text Gene Mentions
Abstract)
…All subjects with HH had C282Y homozygosity, and the normal volunteers lacked any HFE gene mutations known to cause HH.…
Abstract)
…"Heart Study ofHemochromatosis" completed 48-hour Holter…
Abstract)
…volunteers lacked anyHFEgene mutations which…
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…HFE…
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It is not well known whether systemic iron overload per se in hereditary hemochromatosis (HH) is associated with cardiac arrhythmias before other signs and symptoms of cardiovascular disease occur. In the present study, we examined the incidence of cardiac arrhythmia in cardiac asymptomatic subjects with HH (New York Heart Association functional class I) and compared it to that in age- and gender-matched normal volunteers. The 42 subjects with HH and the 19 normal control subjects were recruited through the National Heart, Lung, and Blood Institute-sponsored "Heart Study of Hemochromatosis." They completed 48-hour Holter electrocardiography ambulatory monitoring at the baseline evaluation. The subjects with HH were classified as newly diagnosed (group A) and chronically treated (group B) subjects. All subjects with HH had C282Y homozygosity, and the normal volunteers lacked any HFE gene mutations known to cause HH. Although statistically insignificant, the incidence of ventricular and supraventricular ectopy tended to be greater in the combined HH groups than in the controls. Supraventricular ectopy was more frequently noted in group B compared to in the controls (ectopy rate per hour 11.1 ± 29.9 vs 1.5 ± 3.5, p < 0.05, using the Kruskal-Wallis test). No examples of heart block, other than first-degree atrioventricular node block, were seen in any of the subjects. The incidence of cardiac arrhythmias was not significantly reduced after 6 months of intensive iron removal therapy in the group A subjects. No life-threatening arrhythmias were observed in our subjects with HH. In conclusion, our data suggest that the incidence of cardiac arrhythmias is, at most, marginally increased in asymptomatic subjects with HH. A larger clinical study is warranted to further clarify our observation.
Inflammation and oxidative stress, elicited by Trypanosoma cruzi infection, are important pathologic events during progressive Chagasic cardiomyopathy. In this study, we infected Sprague-Dawley rats with T. cruzi, and treated with phenyl-α-tert-butylnitrone (PBN-antioxidant) and/or benznidazole (BZ-anti-parasite). We employed two-dimensional gel electrophoresis/mass spectrometry to investigate (a) the plasma proteomic changes associated with infection and disease development, and (b) the beneficial effects of PBN and BZ in controlling the disease-associated plasma profile. Matrix-assisted laser desorption ionization/time of flight (MALDI-TOF) tandem MS (MS/MS) analysis of differentially expressed (total 146) and oxidized (total 48) protein spots yielded 92 unique proteins. Our data showed that treatment with PBN and BZ restored the differential expression of 65% and 30% of the disease-associated proteins to normal level, respectively, and PBN prevented development of oxidative adducts on plasma proteins. Western blotting to detect dinitrophenyl-derivatized carbonyl-proteins revealed plasma proteins were maximally oxidized during acute infection. Functional and disease/disorder analyses allocated a majority of the differentially expressed and oxidized proteins into inflammation/immunity and lipid metabolism categories and to molecular pathways associated with heart disease (e.g. cardiac infarction, contractile dysfunction, hypertrophy, and hypertension) in chagasic rats, and to curative pathways (e.g. ROS scavenging capacity, immune regulation) in infected rats treated with PBN and/or BZ. We validated the two-dimensional gel electrophoresis results by Western blotting, and demonstrated that the disease-associated increased expression of gelsolin and vimentin and release of cardiac MYL2 in the plasma of chagasic rats was returned to control level by PBN/BZ treatment. Increased plasma levels of gelsolin, MYL2 and vimentin were directly correlated with the severity of cardiac disease in human chagasic patients. Together, these results demonstrate the plasma oxidative and inflammatory response profile, and plasma detection of cardiac proteins parallels the pathologic events contributing to Chagas disease development, and is of potential utility in diagnosing disease severity and designing suitable therapy for management of human chagasic patients.
Also flagged:Gli2MEF2Ctranscription factorsglioma-associated factor 2Shhmyocyte enhancer factor 2C
Journal Article2011-12-22No SnippetsVoronova A, Al Madhoun A, Fischer A, Shelton M, Karamboulas C, Skerjanc IS.
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The transcription factors Gli2 (glioma-associated factor 2), which is a transactivator of Sonic Hedgehog (Shh) signalling, and myocyte enhancer factor 2C (MEF2C) play important roles in the development of embryonic heart muscle and enhance cardiomyogenesis in stem cells. Although the physiological importance of Shh signalling and MEF2 factors in heart development is well known, the mechanistic understanding of their roles is unclear. Here, we demonstrate that Gli2 and MEF2C activated each other's expression while enhancing cardiomyogenesis in differentiating P19 EC cells. Furthermore, dominant-negative mutant proteins of either Gli2 or MEF2C repressed each other's expression, while impairing cardiomyogenesis in P19 EC cells. In addition, chromatin immunoprecipitation (ChIP) revealed association of Gli2 to the Mef2c gene, and of MEF2C to the Gli2 gene in differentiating P19 cells. Finally, co-immunoprecipitation studies showed that Gli2 and MEF2C proteins formed a complex, capable of synergizing on cardiomyogenesis-related promoters containing both Gli- and MEF2-binding elements. We propose a model whereby Gli2 and MEF2C bind each other's regulatory elements, activate each other's expression and form a protein complex that synergistically activates transcription, enhancing cardiac muscle development. This model links Shh signalling to MEF2C function during cardiomyogenesis and offers mechanistic insight into their in vivo functions.
Dermal hyperpigmentation or Fibromelanosis (FM) is one of the few examples of skin pigmentation phenotypes in the chicken, where most other pigmentation variants influence feather color and patterning. The Silkie chicken is the most widespread and well-studied breed displaying this phenotype. The presence of the dominant FM allele results in extensive pigmentation of the dermal layer of skin and the majority of internal connective tissue. Here we identify the causal mutation of FM as an inverted duplication and junction of two genomic regions separated by more than 400 kb in wild-type individuals. One of these duplicated regions contains endothelin 3 (EDN3), a gene with a known role in promoting melanoblast proliferation. We show that EDN3 expression is increased in the developing Silkie embryo during the time in which melanoblasts are migrating, and elevated levels of expression are maintained in the adult skin tissue. We have examined four different chicken breeds from both Asia and Europe displaying dermal hyperpigmentation and conclude that the same structural variant underlies this phenotype in all chicken breeds. This complex genomic rearrangement causing a specific monogenic trait in the chicken illustrates how novel mutations with major phenotypic effects have been reused during breed formation in domestic animals.
Also flagged:Protein kinase AHeat shock factor 1HSF1neurodegenerative disordersHuntington's diseaseserine
Journal Article2011-12-22✓ 1 SnippetZhang Y, Murshid A, Prince T, Calderwood SK.
In-Text Gene Mentions
Results)
…tract (poly-25Q orHtt94Q-CFP) was found…
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Heat shock factor 1 (HSF1) regulates one of the major pathways of protein quality control and is essential for deterrence of protein-folding disorders, particularly in neuronal cells. However, HSF1 activity declines with age, a change that may open the door to progression of neurodegenerative disorders such as Huntington's disease. We have investigated mechanisms of HSF1 regulation that may become compromised with age. HSF1 binds stably to the catalytic domain of protein kinase A (PKAcα) and becomes phosphorylated on at least one regulatory serine residue (S320). We show here that PKA is essential for effective transcription of HSP genes by HSF1. PKA triggers a cascade involving HSF1 binding to the histone acetylase p300 and positive translation elongation factor 1 (p-TEFb) and phosphorylation of the c-terminal domain of RNA polymerase II, a key mechanism in the downstream steps of HSF1-mediated transcription. This cascade appears to play a key role in protein quality control in neuronal cells expressing aggregation-prone proteins with long poly-glutamine (poly-Q) tracts. Such proteins formed inclusion bodies that could be resolved by HSF1 activation during heat shock. Resolution of the inclusions was inhibited by knockdown of HSF1, PKAcα, or the pTEFb component CDK9, indicating a key role for the HSF1-PKA cascade in protein quality control.
Also flagged:proteasomedegradationHuntington's diseaseHDautosomal dominant neurodegenerative disorderpolyglutamine
Journal Article2011-12-22✓ 5 SnippetsButler DC, Messer A.
In-Text Gene Mentions
Abstract)
…This results in misfolding and accumulation of huntingtin protein ( htt ) , formation of neuronal intranuclear and cytoplasmic inclusions…
Abstract)
…In ST14A cells, fusion of the C-terminal PEST region of mouse ornithine decarboxylase (mODC) to scFv-C4 reduces htt exon 1 protein fragments with 72 glutamine repeats (httex1-72Q) by ∼80–90% when compared to scFv-C4 alone.…
Results)
…Because the targeted epitope of scFv-C4 is the N-terminal 17 amino acids of htt, scFv-C4 and scFv-C4-PEST are likely to bind a variety of N-terminal mhtt fragments produced from the cleavage of full-length mhtt during HD pathology.…
Discussion)
…One very promising candidate, the scFv intrabody scFv-C4, targets the N-terminal 17 amino acids of the htt protein, a domain of htt protein that is increasingly being recognized as pivotal in mediating physiological and pathological pathways in HD [41].…
Introduction)
…A naïve human spleen scFv phage-display library screened against the N-terminal 17 amino acids of htt generated the scFv-C4 intrabody, which successfully counteracts in situ length-dependent htt aggregation, in both cell culture [18], [19], [20], [21] and Drosophila models of HD [22].…
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Huntington's disease (HD) is a fatal autosomal dominant neurodegenerative disorder caused by a trinucleotide (CAG)(n) repeat expansion in the coding sequence of the huntingtin gene, and an expanded polyglutamine (>37Q) tract in the protein. This results in misfolding and accumulation of huntingtin protein (htt), formation of neuronal intranuclear and cytoplasmic inclusions, and neuronal dysfunction/degeneration. Single-chain Fv antibodies (scFvs), expressed as intrabodies that bind htt and prevent aggregation, show promise as immunotherapeutics for HD. Intrastriatal delivery of anti-N-terminal htt scFv-C4 using an adeno-associated virus vector (AAV2/1) significantly reduces the size and number of aggregates in HDR6/1 transgenic mice; however, this protective effect diminishes with age and time after injection. We therefore explored enhancing intrabody efficacy via fusions to heterologous functional domains. Proteins containing a PEST motif are often targeted for proteasomal degradation and generally have a short half life. In ST14A cells, fusion of the C-terminal PEST region of mouse ornithine decarboxylase (mODC) to scFv-C4 reduces htt exon 1 protein fragments with 72 glutamine repeats (httex1-72Q) by ~80-90% when compared to scFv-C4 alone. Proteasomal targeting was verified by either scrambling the mODC-PEST motif, or via proteasomal inhibition with epoxomicin. For these constructs, the proteasomal degradation of the scFv intrabody proteins themselves was reduced<25% by the addition of the mODC-PEST motif, with or without antigens. The remaining intrabody levels were amply sufficient to target N-terminal httex1-72Q protein fragment turnover. Critically, scFv-C4-PEST prevents aggregation and toxicity of httex1-72Q fragments at significantly lower doses than scFv-C4. Fusion of the mODC-PEST motif to intrabodies is a valuable general approach to specifically target toxic antigens to the proteasome for degradation.
Also flagged:Phosphorylationcore proteindephosphorylationcorealanineaspartic acid
Journal Article2011-12-22✓ 5 SnippetsLudgate L, Adams C, Hu J.
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S I O 001029)
…Cells were transfected with the indicated plasmids expressing either GST or GST-DCC fusion proteins, then were metabolically labeled with either [35S]cysteine/methionine or [32P]orthophosphate on the third day post-transfection.…
S I O 001029)
…The GST-DCC fusion proteins were named by their amino acid starting position and their phosphosite substitutions.…
Methods)
…DHBc CTD (DCC) coding sequences (from…
Methods)
…the GST-DHBc CTD (GST-DCC) fusion proteins in…
Methods)
…expression of the GST-DCCfusion proteins, the…
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Dynamic phosphorylation and dephosphorylation of the hepadnavirus core protein C-terminal domain (CTD) are required for multiple steps of the viral life cycle. It remains unknown how the CTD phosphorylation state may modulate core protein functions but phosphorylation state-dependent viral or host interactions may play a role. In an attempt to identify host factors that may interact differentially with the core protein depending on its CTD phosphorylation state, pulldown assays were performed using the CTD of the duck hepatitis B virus (DHBV) and human hepatitis B virus (HBV) core protein, either with wild type (WT) sequences or with alanine or aspartic acid substitutions at the phosphorylation sites. Two host proteins, B23 and I2PP2A, were found to interact preferentially with the alanine-substituted CTD. Furthermore, the WT CTD became competent to interact with the host proteins upon dephosphorylation. Intriguingly, the binding site on the DHBV CTD for both B23 and I2PP2A was mapped to a region upstream of the phosphorylation sites even though B23 or I2PP2A binding to this site was clearly modulated by the phosphorylation state of the downstream and non-overlapping sequences. Together, these results demonstrate a novel mode of phosphorylation-regulated protein-protein interaction and provide new insights into virus-host interactions.
Also flagged:synthesisCox1Cox2phenyl estersibuprofenicmefenamic acids
Journal Article2011-12-22No SnippetsHegazy GH, Ali HI.
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Nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently associated with gastric mucosal and renal adverse reactions, related to inhibition of cyclooxygenase1 (Cox1) in tissues where prostaglandins exert physiological effects. This led us to develop a set of ibuprofenic acid and mefenamic acid esters, namely: 4-((4-substituted benzylidene)amino)phenyl 2-(4-isobutylphenyl)propanoate and 4-((4-substituted benzylidene)amino)phenyl 2-((2,4-dimethylphenyl)amino)benzoate analogs, which were synthesized by condensation of the corresponding acids with Schiff's bases [4-(4-substituted benzylideneamino)phenols] involving dicyclohexyl carbodiimmide (DCC) as mild dehydrating agent. The main objective is to reduce the GIT toxicity associated with acute and chronic NSAIDs use. Anti-inflammatory, analgesic as well as ulcerogenic activities of the prepared esters were evaluated in vivo and compared with that of ibuprofen as reference standard in all screenings, involving the carrageenan induced paw oedema model and hot plate method. Most of the synthesized esters showed remarkable analgesic and anti-inflammatory activities. Interestingly, all of the compounds were found to be non-ulcerogenic under the tested conditions. This evidence have suggested that modification of the carboxyl function of representative NSAIDs results in retained or enhanced anti-inflammatory and analgesic activities with reduced ulcerogenic potential. Additionally, a comparative AutoDock study into Cox 1 and Cox2 has been done involving both of rigid and flexible docking for potential selectivity of our compounds within different Cox enzymes and to find out the binding orientation of these novel esters into their binding site. Some of the newly prepared aforementioned compounds showed considerable more Cox2 over Cox1 binding affinities by flexible docking better than rigid one.
Chromosome pairing is usually discussed in the context of meiosis. Association of homologues in germ cells enables chromosome segregation and is necessary for fertility. A few organisms, such as flies, also pair their entire genomes in somatic cells. Most others, including mammals, display little homologue pairing outside of the germline. Experimental evidence from both flies and mammals suggests that communication between homologues contributes to normal genome regulation. This paper will contrast the role of pairing in transmitting information between homologues in flies and mammals. In mammals, somatic homologue pairing is tightly regulated, occurring at specific loci and in a developmentally regulated fashion. Inappropriate pairing, or loss of normal pairing, is associated with gene misregulation in some disease states. While homologue pairing in flies is capable of influencing gene expression, the significance of this for normal expression remains unknown. The sex chromosomes pose a particularly interesting situation, as females are able to pair X chromosomes, but males cannot. The contribution of homologue pairing to the biology of the X chromosome will also be discussed.
Tooth caries is a carbohydrate-modified bacterial infectious disease, and recurrent caries is a frequent reason for restoration failure. The objective of this study was to develop a novel antibacterial composite using tetracalcium phosphate (TTCP) fillers and bis(2-methacryloyloxy-ethyl) dimethyl-ammonium bromide, which is a quaternary ammonium dimethacrylate (QADM). QADM was synthesized using 2-(N,N-dimethylamino)ethyl methacrylate and 2-bromoethyl methacrylate and incorporated into a resin. The resin was filled with 40% TTCP and 30% glass particles. The following QADM mass fractions in the composite were tested: 0%, 6%, 12%, and 18%. Streptococcus mutans biofilms were formed on the composites and the colony-forming units (CFUs), metabolic activity, and lactic acid production were measured. The TTCP-QADM composite had flexural strength and elastic modulus similar to those of two commercial composites (p > 0.1). Increasing the QADM content in TTCP composite greatly decreased the bacteria growth and biofilm matrix production. There were significantly more dead bacteria with increasing QADM content. TTCP composite containing 18% QADM had biofilm CFU, metabolic activity, and acid production about half of those without QADM. Inversely linear relationships were established between QADM mass fraction and S. mutans biofilm CFU, metabolic activity, and acid production, with correlation coefficients R(2) ≥ 0.98. In conclusion, TTCP-QADM composites were developed and the effect of QADM mass fraction on the antibacterial properties of the composite was determined for the first time. The novel TTCP-QADM composites possessing a strong antibacterial capability, together with calcium phosphate ion release and good mechanical properties, are promising for dental restorations to reduce biofilm growth and recurrent caries.
Journal Article2011-12-21✓ 1 SnippetYan KS, Chia LA, Li X, Ootani A, Su J, Lee JY, Su N, Luo Y, Heilshorn SC, Amieva MR, Sangiorgi E, Capecchi MR, Kuo CJ.
In-Text Gene Mentions
I A O 0000326)
…Olfm4…
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The small intestine epithelium undergoes rapid and continuous regeneration supported by crypt intestinal stem cells (ISCs). Bmi1 and Lgr5 have been independently identified to mark long-lived multipotent ISCs by lineage tracing in mice; however, the functional distinctions between these two populations remain undefined. Here, we demonstrate that Bmi1 and Lgr5 mark two functionally distinct ISCs in vivo. Lgr5 marks mitotically active ISCs that exhibit exquisite sensitivity to canonical Wnt modulation, contribute robustly to homeostatic regeneration, and are quantitatively ablated by irradiation. In contrast, Bmi1 marks quiescent ISCs that are insensitive to Wnt perturbations, contribute weakly to homeostatic regeneration, and are resistant to high-dose radiation injury. After irradiation, however, the normally quiescent Bmi1(+) ISCs dramatically proliferate to clonally repopulate multiple contiguous crypts and villi. Clonogenic culture of isolated single Bmi1(+) ISCs yields long-lived self-renewing spheroids of intestinal epithelium that produce Lgr5-expressing cells, thereby establishing a lineage relationship between these two populations in vitro. Taken together, these data provide direct evidence that Bmi1 marks quiescent, injury-inducible reserve ISCs that exhibit striking functional distinctions from Lgr5(+) ISCs and support a model whereby distinct ISC populations facilitate homeostatic vs. injury-induced regeneration.
Notch signaling is known to regulate the proliferation and differentiation of intestinal stem and progenitor cells; however, direct cellular targets and specific functions of Notch signals had not been identified. We show here in mice that Notch directly targets the crypt base columnar (CBC) cell to maintain stem cell activity. Notch inhibition induced rapid CBC cell loss, with reduced proliferation, apoptotic cell death and reduced efficiency of organoid initiation. Furthermore, expression of the CBC stem cell-specific marker Olfm4 was directly dependent on Notch signaling, with transcription activated through RBP-Jκ binding sites in the promoter. Notch inhibition also led to precocious differentiation of epithelial progenitors into secretory cell types, including large numbers of cells that expressed both Paneth and goblet cell markers. Analysis of Notch function in Atoh1-deficient intestine demonstrated that the cellular changes were dependent on Atoh1, whereas Notch regulation of Olfm4 gene expression was Atoh1 independent. Our findings suggest that Notch targets distinct progenitor cell populations to maintain adult intestinal stem cells and to regulate cell fate choice to control epithelial cell homeostasis.
Also flagged:glutaric anhydridealbuminBSAovalbumin,2chlorophenyl
Journal Article2011-12-20No SnippetsHongsibsong S, Wipasa J, Pattarawarapan M, Chantara S, Stuetz W, Nosten F, Prapamontol T.
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1,1-Dichloro-2,2-bis(p-chlorophenyl) ethylene (p,p'-DDE) is the major metabolite of insecticide 2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane (p,p'-DDT) and a persistent organic pollutant (POPs) with concerns regarding its bioaccumulation and persistence in the environment and food chain. In the present study, an indirect competitive enzyme-linked immunosorbant assay (ic-ELISA) specific for the detection of p,p'-DDE is described. In hapten synthesis, 2,2'-bis(4-chlorophenyl)ethanol and glutaric anhydride were used as precursor and spacer arm, respectively. The hapten was then conjugated to bovine serum albumin (BSA) as immunogen for mouse immunization and also conjugated to ovalbumin as coating antigen for ELISA. The developed ic-ELISA was used for detecting p,p'-DDE in human milk samples and validated against the results from conventional gas chromatography-electron capture detection (GC-ECD). Coefficients of variation (%CV) of ELISA were 5.7-10.4% for intra-assay and 10.6-19.6% for interassay variations. The Pearson correlation coefficient of p,p'-DDE concentrations between ic-ELISA and GC-ECD was r = 0.766, which was in an acceptable range. The results indicate that the developed assay could be an alternative analytical tool for monitoring p,p'-DDE in lipimic matrices such as human milk.
Also flagged:hypothyroidismnonalcoholic fatty liver diseaseNAFLDNASHalcoholLiver disease
Journal Article2011-12-20✓ 1 SnippetPagadala MR, Zein CO, Dasarathy S, Yerian LM, Lopez R, McCullough AJ.
In-Text Gene Mentions
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…hemochromatosis…
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<h4>Background</h4>A possible association between nonalcoholic fatty liver disease (NAFLD) and hypothyroidism has been suggested. The recognized link between hypothyroidism and elements of the metabolic syndrome may explain this association.<h4>Aim</h4>The purpose of this study was to determine the prevalence of hypothyroidism in a cohort of patients with NAFLD and analyze the potential factors associated with hypothyroidism in this patient population.<h4>Methods</h4>Two hundred forty-six patients with biopsy-proven NAFLD attending hepatology clinics at the Cleveland Clinic between October 2006 and June 2009, and 430 age-, gender-, race- and BMI-matched control subjects seen in the general internal medicine clinic were included. Patients with a clinical diagnosis of hypothyroidism who were on thyroid replacement therapy were considered to be hypothyroid.<h4>Results</h4>Hypothyroidism was more frequent among patients with NAFLD (21% vs. 9.5%; P < 0.01) compared to controls, and was higher in NASH patients than NAFLD patients without NASH (25% vs. 12.8%, P = 0.03). Subjects with hypothyroidism were 2.1 (95% CI 1.1-3.9, P = 0.02) and 3.8 (95% CI 2-6.9, P < 0.001) times more likely to have NAFLD and NASH, respectively. By multivariate analysis, female gender (P < 0.001) and increased BMI (P = 0.03) were associated with hypothyroidism. NAFLD subjects who reported mild alcohol consumption were less likely to have hypothyroidism compared to those who reported complete abstinence (OR 0.37, P = 0.008).<h4>Conclusions</h4>A higher prevalence of hypothyroidism was demonstrated in patients with NAFLD compared to controls. Among subjects with NALFD, female gender, increased BMI and history of abstinence from alcohol were associated with hypothyroidism. Patients with hypothyroidism were also more likely to have NASH.
Also flagged:HHTarteriovenous malformationsmetabolismnitric oxide synthaseNOSHereditary Hemorrhagic Telangiectasia
Journal Article2011-12-20No SnippetsJamshidi N, Miller FJ, Mandel J, Evans T, Kuo MD.
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<h4>Background</h4>Hereditary Hemorrhagic Telangiectasia (HHT) is an autosomal dominant disease with a varying range of phenotypes involving abnormal vasculature primarily manifested as arteriovenous malformations in various organs, including the nose, brain, liver, and lungs. The varied presentation and involvement of different organ systems makes the choice of potential treatment medications difficult.<h4>Results</h4>A patient with a mixed-clinical presentation and presumed diagnosis of HHT, severe exertional dyspnea, and diffuse pulmonary shunting at the microscopic level presented for treatment. We sought to analyze her metabolomic plasma profile to assist with pharmacologic treatment selection. Fasting serum samples from 5 individuals (4 healthy and 1 with HHT) were metabolomically profiled. A global metabolic network reconstruction, Recon 1, was used to help guide the choice of medication via analysis of the differential metabolism between the patient and healthy controls using metabolomic data. Flux Balance Analysis highlighted changes in metabolic pathway activity, notably in nitric oxide synthase (NOS), which suggested a potential link between changes in vascular endothelial function and metabolism. This finding supported the use of an already approved medication, bevacizumab (Avastin). Following 2 months of treatment, the patient's metabolic profile shifted, becoming more similar to the control subject profiles, suggesting that the treatment was addressing at least part of the pathophysiological state.<h4>Conclusions</h4>In this 'individualized case study' of personalized medicine, we carry out untargeted metabolomic profiling of a patient and healthy controls. Rather than filtering the data down to a single value, these data are analyzed in the context of a network model of metabolism, in order to simulate the biochemical phenotypic differences between healthy and disease states; the results then guide the therapy. This presents one approach to achieving the goals of individualized medicine through Systems Biology and causal models analysis.
Amino acids are safe molecules with variable efficacy against ulceration. Considering the good antioxidant potential of N-aroyl- N, N'-dicyclohexyl urea and antiulcer activities of amino acids, a series of amino acid conjugates of N-aroyl- N, N'-dicyclohexyl urea was synthesized and the effect against ulceration in albino rats induced by pyloric ligation was screened. All these compounds were found to be safe and active. Reduction of ulcer index was significant for all compounds. Conjugates of methionine and histidine exhibited enhanced antiulcer activity comparable to omeprazole in terms of inhibition of release of gastric juice, hydrochloric acid and neutralization activity. The promising efficacy and safety of these compounds is interesting for further investigation.
Also flagged:Tristetraprolinimmune responsebindingTTPp38 MAPKcytokine
Journal Article2011-12-20No SnippetsKratochvill F, Machacek C, Vogl C, Ebner F, Sedlyarov V, Gruber AR, Hartweger H, Vielnascher R, Karaghiosoff M, Rülicke T, Müller M, Hofacker I, Lang R, Kovarik P.
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For a successful yet controlled immune response, cells need to specifically destabilize inflammatory mRNAs but prevent premature removal of those still used. The regulatory circuits controlling quality and timing in the global inflammatory mRNA decay are not understood. Here, we show that the mRNA-destabilizing function of the AU-rich element-binding protein tristetraprolin (TTP) is inversely regulated by the p38 MAPK activity profile such that after inflammatory stimulus the TTP-dependent decay is initially limited to few mRNAs. With time, the TTP-dependent decay gradually spreads resulting in cumulative elimination of one third of inflammation-induced unstable mRNAs in macrophages in vitro. We confirmed this sequential decay model in vivo since LPS-treated mice with myeloid TTP ablation exhibited similar cytokine dysregulation profile as macrophages. The mice were hypersensitive to LPS but otherwise healthy with no signs of hyperinflammation seen in conventional TTP knockout mice demonstrating the requirement for myeloid TTP in re-installment but not maintenance of immune homeostasis. These findings reveal a TTP- and p38 MAPK-dominated regulatory mechanism that is vital for balancing acute inflammation by a temporally and qualitatively controlled mRNA decay.
RNA interference (RNAi) has been extensively employed for in vivo research since its use was first demonstrated in mammalian cells 10 years ago. Design rules have improved, and it is now routinely possible to obtain reagents that suppress expression of any gene desired. At the same time, increased understanding of the molecular basis of unwanted side effects has led to the development of chemical modification strategies that mitigate these concerns. Delivery remains the single greatest hurdle to widespread adoption of in vivo RNAi methods. However, exciting advances have been made and new delivery systems under development may help to overcome these barriers. This review discusses advances in RNAi biochemistry and biology that impact in vivo use and provides an overview of select publications that demonstrate interesting applications of these principles. Emphasis is placed on work with synthetic, small interfering RNAs (siRNAs) published since the first installment of this review which appeared in 2006.
Also flagged:pathogenesisHuntington diseaseHDneurodegenerative disorderspolyglutaminepeptides
Journal Article2011-12-20✓ 5 SnippetsGupta S, Jie S, Colby DW.
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Abstract)
…Using synthetic polyglutamine peptides as the substrate for amyloid formation, we found that partially purified misfolded HTT obtained from end-stage brain tissue of two Tg HD mouse models and brain tissue of post-mortem human HD patients was capable of specifically accelerating polyglutamine amyloid formation compared with unseeded reactions and controls.…
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…The sensitive detection of misfolded HTT protein early in the disease pathogenesis in the YAC128 Tg mouse model strengthens the argument for a causative role of protein misfolding in HD.…
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…sensitive detection of misfolded HTT protein early in the…
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…Here, we report a novel method for the sensitive detection of misfolded huntingtin (HTT) isolated from the brains of transgenic (Tg) mouse models of HD and humans with HD using an amyloid seeding assay (ASA), which is based on the propensity of misfolded proteins to act as a seed and shorten the nucleation-associated lag phase in the kinetics of amyloid formation in vitro.…
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…HTT…
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Huntington disease (HD) is one of several fatal neurodegenerative disorders associated with misfolded proteins. Here, we report a novel method for the sensitive detection of misfolded huntingtin (HTT) isolated from the brains of transgenic (Tg) mouse models of HD and humans with HD using an amyloid seeding assay (ASA), which is based on the propensity of misfolded proteins to act as a seed and shorten the nucleation-associated lag phase in the kinetics of amyloid formation in vitro. Using synthetic polyglutamine peptides as the substrate for amyloid formation, we found that partially purified misfolded HTT obtained from end-stage brain tissue of two Tg HD mouse models and brain tissue of post-mortem human HD patients was capable of specifically accelerating polyglutamine amyloid formation compared with unseeded reactions and controls. Alzheimer and prion disease brain tissues did not do so, demonstrating the specificity of the ASA. It is unclear whether early intermediates or later conformational species in the protein misfolding process act as seeds in the ASA for HD. However, we were able to detect misfolded protein in the brains of YAC128 mice early in disease pathogenesis (11 weeks of age), whereas large inclusion bodies have not been observed in the brains of these mice by histology until 78 weeks of age, much later in the pathogenic process. The sensitive detection of misfolded HTT protein early in the disease pathogenesis in the YAC128 Tg mouse model strengthens the argument for a causative role of protein misfolding in HD.
…Subcellular fractionation of peripheral blood neutrophils demonstrated complete colocalization of OLFM4 with the specific granule protein NGAL, and stimulation of neutrophils with PMA resulted in corelease of NGAL and OLFM4, proving that OLFM4 is a genuine constituent of neutrophil-specific granules.…
Abstract)
…OLFM4 was, however, present in only 20-25% of peripheral blood neutrophils, as determined by immunocytochemistry and flow cytometry, whereas mRNA for OLFM4 was present in all MY/MM, indicating post-transcriptional regulation as a basis for the heterogeneous expression of OLFM4 protein.…
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…OLFM4was identified initially…
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…data predicted thatOLFM4would be associated…
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…complete colocalization ofOLFM4with the specific…
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OLFM4 was identified initially as a gene highly induced in myeloid stem cells by G-CSF treatment. A bioinformatics method using a global meta-analysis of microarray data predicted that OLFM4 would be associated with specific granules in human neutrophils. Subcellular fractionation of peripheral blood neutrophils demonstrated complete colocalization of OLFM4 with the specific granule protein NGAL, and stimulation of neutrophils with PMA resulted in corelease of NGAL and OLFM4, proving that OLFM4 is a genuine constituent of neutrophil-specific granules. In accordance with this, OLFM4 mRNA peaked at the MY/MM stage of maturation. OLFM4 was, however, present in only 20-25% of peripheral blood neutrophils, as determined by immunocytochemistry and flow cytometry, whereas mRNA for OLFM4 was present in all MY/MM, indicating post-transcriptional regulation as a basis for the heterogeneous expression of OLFM4 protein.
The Sin3a/HDAC co-repressor complex is a critical regulator of transcription networks that govern cell cycle control and apoptosis throughout development. Previous studies have identified Sin3a as essential for embryonic development around the time of implantation, during which the epiblast cell cycle is uniquely structured to achieve very rapid divisions with little tolerance of DNA damage. This study investigates the specific requirement for Sin3a in the early mouse embryo and shows that embryos lacking Sin3a suffer unresolved DNA damage and acute p53-independent apoptosis specifically in the E3.5-4.5 epiblast. Surprisingly, Myc and E2F targets in Sin3a-null ICMs are downregulated, suggesting a central but non-canonical role for Sin3a in regulating the pluripotent embryonic cell cycle. ES cells deleted for Sin3a mount a DNA damage response indicative of unresolved double-strand breaks, profoundly arrest at G2, and undergo apoptosis. These results indicate that Sin3a protects the genomic integrity of pluripotent embryonic cells and governs their unusual cell cycle.
Also flagged:cancermethotrexateamidoaminedendrimercancersphoton
Journal Article2011-12-20No SnippetsChoi SK, Verma M, Silpe J, Moody RE, Tang K, Hanson JJ, Baker JR.
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Photochemistry provides a unique mechanism that enables the active control of drug release in cancer-targeting drug delivery. This study investigates the light-mediated release of methotrexate, an anticancer drug, using a photocleavable linker strategy based on o-nitrobenzyl protection. We evaluated two types of the o-nitrobenzyl-linked methotrexate for the drug release study and further extended the study to a fifth-generation poly(amidoamine) dendrimer carrier covalently conjugated with methotrexate via the o-nitrobenzyl linker. We performed the drug release studies by using a combination of three standard analytical methods that include UV/vis spectrometry, (1)H NMR spectroscopy, and anal. HPLC. This article reports that methotrexate is released by the photochemical mechanism in an actively controlled manner. The rate of the drug release varies in response to multiple control parameters, including linker design, light wavelength, exposure time, and the pH of the medium where the drug release occurs.
Also flagged:oligomycinfolatechitosantumorOligomycin-Asodium tripolyphosphate
Journal Article2011-12-20No SnippetsZu Y, Zhao Q, Zhao X, Zu S, Meng L.
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Oligomycin-A (Oli-A), an anticancer drug, was loaded to the folate (FA)-conjugated chitosan as a tumor-targeted drug delivery system for the purpose of overcoming the nonspecific targeting characteristics and the hydrophobicity of the compound. The two-level factorial design (2-LFD) was applied to modeling the preparation process, which was composed of five independent variables, namely FA-conjugated chitosan (FA-CS) concentration, Oli-A concentration, sodium tripolyphosphate (TPP) concentration, the mass ratio of FA-CS to TPP, and crosslinking time. The mean particle size (MPS) and the drug loading rate (DLR) of the resulting Oli-loaded FA-CS nanoparticles (FA-Oli-CSNPs) were used as response variables. The interactive effects of the five independent variables on the response variables were studied. The characteristics of the nanoparticles, such as amount of FA conjugation, drug entrapment rate (DER), DLR, surface morphology, and release kinetics properties in vitro were investigated. The FA-Oli-CSNPs with MPS of 182.6 nm, DER of 17.3%, DLR of 58.5%, and zeta potential (ZP) of 24.6 mV were obtained under optimum conditions. The amount of FA conjugation was 45.9 mg/g chitosan. The FA-Oli-CSNPs showed sustained-release characteristics for 576 hours in vitro. The results indicated that FA-Oli-CSNPs obtained as a targeted drug delivery system could be effective in the therapy of leukemia in the future.
Also flagged:CNKSR2developmental delayepilepsymicrocephalyCNK2mental retardation
Journal Article2011-12-20✓ 1 SnippetHouge G, Rasmussen IH, Hovland R.
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In a non-dysmorphic 5-year-old boy with developmental delay, well-controlled epilepsy, and microcephaly, a 234-kb deletion of Xp22.12 was detected by copy number analysis. The maternally inherited deletion removed the initial 15 of the 21 exons of the connector enhancer of KSR-2 gene called CNKSR2 or CNK2. Our finding suggests that loss of CNKSR2 is a novel cause of non-syndromic X-linked mental retardation, an assumption supported by high gene expression in the brain, localization to the post-synaptic density, and a role in RAS/MAPK-dependent signal transduction.
Also flagged:NAFLDfatty livernon-alcoholic fatty liver diseaseCarbohydratetriglycerideaspartate aminotransferase
Journal Article2011-12-20✓ 1 SnippetArefhosseini SR, Ebrahimi-Mameghani M, Farsad Naeimi A, Khoshbaten M, Rashid J.
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…hemochromatosis…
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<h4>Background</h4>Prevalence of non-alcoholic fatty liver disease (NAFLD) is more common worldwide and no certain treatment apart from lifestyle modification has been established yet. Available data consistently show that energy intake is significantly higher in patients with NAFLD than in individuals with no evidence of fatty liver. Changing nutritional behaviors seems to be the primary approach for treatment, simultaneously addressing all the clinical and biochemical defects. This study was aimed to examine the effects of two different composition of low energy diet (diet I vs. diet II) on non-alcoholic fatty liver disease patients.<h4>Methods</h4>In this double-blind randomized controlled trial, 44 ultrasonography-proven overweight non-alcoholic fatty liver disease patients were divided into two groups and received two low-energy diets (-500 kcal less than energy requirement individually) inc. diet I (Carbohydrate: Fat: Protein: 55:25:20) and diet II (Carbohydrate: Fat: Protein: 40:40:20) for six weeks. Anthropometric and biochemical measures as well as liver enzymes were assessed after 12 hours fasting.<h4>Results</h4>After diet I and diet II, weight decreased significantly (%1.82 and %2.45, respectively). Liver enzymes and echogenicity decreased significantly by both diet I and diet II. Mean of triglyceride concentration decreased (%18.09) after diet II (P=0.023), while there was no significant change after diet I. Significant correlations were found between changes in aspartate aminotransferase with triglyceride and LDL-C diet I.<h4>Conclusion</h4>Low energy diets can decrease liver enzymes regardless of their composition, while diet II seems to be more effective than diet I in reduction of weight and triglyceride level.
The rocaglates/rocaglamides are a class of natural products known to display potent anticancer activity. One such derivative, silvestrol, has shown activity comparable to taxol in certain settings. Here, we report the synthesis of various rocaglamide analogues and identification of a hydroxamate derivative (-)-9 having activity similar to silvestrol in vitro and ex vivo for inhibition of protein synthesis. We also show that (-)-9 synergizes with doxorubicin in vivo to reduce Eμ-Myc driven lymphomas.
<h4>Objective</h4>To evaluate the presence of pulmonary abnormalities in rheumatoid arthritis (RA)-related autoantibody-positive subjects without inflammatory arthritis.<h4>Methods</h4>Forty-two subjects who did not have inflammatory arthritis but were positive for anti-cyclic citrullinated peptide antibodies and/or ≥2 rheumatoid factor isotypes (a profile that is 96% specific for RA), 15 autoantibody-negative controls, and 12 patients with established seropositive early RA (<1-year duration) underwent spirometry and high-resolution computed tomography (HRCT) lung imaging.<h4>Results</h4>The median age of autoantibody-positive subjects was 54 years, 52% were female, and 38% were ever-smokers; these characteristics were not significantly different from those of autoantibody-negative control subjects. No autoantibody-positive subject had inflammatory arthritis based on joint examination. HRCT revealed that 76% of autoantibody-positive subjects had airways abnormalities including bronchial wall thickening, bronchiectasis, centrilobular opacities, and air trapping, compared with 33% of autoantibody-negative controls (P = 0.005). The prevalence and type of lung abnormalities among autoantibody-positive subjects were similar to those among patients with early RA. In 2 autoantibody-positive subjects with airways disease, inflammatory arthritis classifiable as articular RA developed ∼13 months after the lung evaluation.<h4>Conclusion</h4>Airways abnormalities that are consistent with inflammation are common in autoantibody-positive subjects without inflammatory arthritis and are similar to airways abnormalities seen in patients with early RA. These findings suggest that the lung may be an early site of autoimmune-related injury and potentially a site of generation of RA-related autoimmunity. Further studies are needed to define the mechanistic role of lung inflammation in the development of RA.
During embryonic morphogenesis, adhesion molecules are required for selective cell-cell interactions. The classical cadherins mediate homophilic calcium-dependent cell adhesion and are founding members of the large and diverse cadherin superfamily. The protocadherins are the largest subgroup within this superfamily, yet their participation in calcium-dependent cell adhesion is uncertain. In this paper, we demonstrate a novel mechanism of adhesion, mediated by a complex of Protocadherin-19 (Pcdh19) and N-cadherin (Ncad). Although Pcdh19 alone is only weakly adhesive, the Pcdh19-Ncad complex exhibited robust adhesion in bead aggregation assays, and Pcdh19 appeared to play the dominant role. Adhesion by the Pcdh19-Ncad complex was unaffected by mutations that disrupt Ncad homophilic binding but was inhibited by a mutation in Pcdh19. In addition, the complex exhibited homophilic specificity, as beads coated with Pcdh19-Ncad did not intermix with Ncad- or Pcdh17-Ncad-coated beads. We propose a model in which association of a protocadherin with Ncad acts as a switch, converting between distinct binding specificities.
Also flagged:eicosanoidspolyunsaturated fatty acidsarachidonic acidprostaglandinsthromboxanesleukotrienes
Journal Article2011-12-19No SnippetsHammond VJ, O'Donnell VB.
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Eicosanoids are oxidation products of C20 polyunsaturated fatty acids (e.g. arachidonic acid) that include prostaglandins, thromboxanes, leukotrienes and hydroperoxy fatty acids. They have important biological roles in vivo, including regulation of renal, cardiovascular and gastrointestinal function. Historically, eicosanoids were thought to mediate their signaling actions exclusively as free acids, however evidence is now emerging that they may also be generated attached to other functional groups including phospholipids and glycerol, and that these more complex forms are pathophysiological signaling mediators in their own right. Early studies showed that exogenously added eicosanoids could become esterified into membrane phospholipids of cells, while more recently, it was uncovered that esterified eicosanoids are formed endogenously. This review summarizes our current knowledge of this area, starting with the early discoveries documenting what is known about eicosanoid generation and their esterification, and moving on to discuss the discovery that esterified eicosanoids are generated endogenously by a number of different cell types. Recent research that is highlighting new structures and functions of these important lipid mediators will be presented. This article is part of a Special Issue entitled: Oxidized phospholipids-their properties and interactions with proteins.
Also flagged:neurodegenerative diseasedeathHDnucleotideglutaminespathogenesis
Journal Article2011-12-19✓ 5 SnippetsArrasate M, Finkbeiner S.
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Abstract)
…Here we will review the state of knowledge of HD, focusing especially on a hallmark pathological feature-intracellular aggregates of mutant Htt called inclusion bodies (IBs).…
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…aggregates of mutantHttcalled inclusion bodies…
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…triggered by misfoldedHttwhose efficacy may…
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…forms of mutantHtt.…
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…Htt…
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Huntington's disease (HD) is an incurable neurodegenerative disease characterized by abnormal motor movements, personality changes, and early death. HD is caused by a mutation in the IT-15 gene that expands abnormally the number of CAG nucleotide repeats. As a result, the translated protein huntingtin contains disease-causing expansions of glutamines (polyQ) that make it prone to misfold and aggregate. While the gene and mutations that cause HD are known, the mechanisms underlying HD pathogenesis are not. Here we will review the state of knowledge of HD, focusing especially on a hallmark pathological feature-intracellular aggregates of mutant Htt called inclusion bodies (IBs). We will describe the role of IBs in the disease. We speculate that IB formation could be just one component of a broader coping response triggered by misfolded Htt whose efficacy may depend on the extent to which it clears toxic forms of mutant Htt. We will describe how IB formation might be regulated and which factors could determine different coping responses in different subsets of neurons. A differential regulation of IB formation as a function of the cellular context could, eventually, explain part of the neuronal vulnerability observed in HD.
…serine threonine kinaseTAOK3, was subsequently confirmed…
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The herpes simplex virus type 1 (HSV-1) structural tegument protein pUL37, which is conserved across the Herpesviridae family, is known to be essential for secondary envelopment during the egress of viral particles. To shed light on additional roles of pUL37 during viral replication a yeast two-hybrid screen of a human brain cDNA library was undertaken. This screen identified ten host cell proteins as potential pUL37 interactors. One of the interactors, serine threonine kinase TAOK3, was subsequently confirmed to interact with pUL37 using an in vitro pulldown assay. Such host cell/pUL37 interactions provide further insights into the multifunctional role of this herpesviral tegument protein.
Also flagged:organizationchromosomelysineleucinenucleuschromosomal regions
Journal Article2011-12-19✓ 1 SnippetRodley CD, Pai DA, Mills TA, Engelke DR, O'Sullivan JM.
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…Condensinhas also been…
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The three-dimensional organization of genomes is dynamic and plays a critical role in the regulation of cellular development and phenotypes. Here we use proximity-based ligation methods (i.e. chromosome conformation capture [3C] and circularized chromosome confrmation capture [4C]) to explore the spatial organization of tRNA genes and their locus-specific interactions with the ribosomal DNA. Directed replacement of one lysine and two leucine tRNA loci shows that tRNA spatial organization depends on both tRNA coding sequence identity and the surrounding chromosomal loci. These observations support a model whereby the three-dimensional, spatial organization of tRNA loci within the nucleus utilizes tRNA gene-specific signals to affect local interactions, though broader organization of chromosomal regions are determined by factors outside the tRNA genes themselves.
The intestinal messenger RNA expression signature is affected by the presence and composition of the endogenous microbiota, with effects on host physiology. The intestine is also characterized by a distinctive micronome. However, it is not known if microbes also impact intestinal gene expression epigenetically. We investigated if the murine caecal microRNA expression signature depends on the presence of the microbiota, and the potential implications of this interaction on intestinal barrier function. Three hundred and thirty four microRNAs were detectable in the caecum of germ-free and conventional male mice and 16 were differentially expressed, with samples from the two groups clustering separately based on their expression patterns. Through a combination of computational and gene expression analyses, including the use of our curated list of 527 genes involved in intestinal barrier regulation, 2,755 putative targets of modulated microRNAs were identified, including 34 intestinal barrier-related genes encoding for junctional and mucus layer proteins and involved in immune regulation. This study shows that the endogenous microbiota influences the caecal microRNA expression signature, suggesting that microRNA modulation is another mechanism through which commensal bacteria impact the regulation of the barrier function and intestinal homeostasis. Through microRNAs, the gut microbiota may impinge a much larger number of genes than expected, particularly in diseases where its composition is altered. In this perspective, abnormally expressed microRNAs could be considered as novel therapeutic targets.
Also flagged:estrogen receptorbreast cancercancerdeathEstrogenER
Journal Article2011-12-19No SnippetsSaha Roy S, Vadlamudi RK.
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Metastatic breast cancer is a life-threatening stage of cancer and is the leading cause of death in advanced breast cancer patients. Estrogen signaling and the estrogen receptor (ER) are implicated in breast cancer progression, and the majority of the human breast cancers start out as estrogen dependent. Accumulating evidence suggests that ER signaling is complex, involving coregulatory proteins and extranuclear actions. ER-coregualtory proteins are tightly regulated under normal conditions with miss expression primarily reported in cancer. Deregulation of ER coregualtors or ER extranuclear signaling has potential to promote metastasis in ER-positive breast cancer cells. This review summarizes the emerging role of ER signaling in promoting metastasis of breast cancer cells, discusses the molecular mechanisms by which ER signaling contributes to metastasis, and explores possible therapeutic targets to block ER-driven metastasis.
Also flagged:Sirt1glutaminedeacetylaseTORC1CREBNAD-dependent protein deacetylase
Journal Article2011-12-18✓ 5 SnippetsJeong H, Cohen DE, Cui L, Supinski A, Savas JN, Mazzulli JR, Yates JR, Bordone L, Guarente L, Krainc D.
In-Text Gene Mentions
Abstract)
…Mutant HTT interferes with the TORC1-CREB interaction to repress BDNF transcription, and Sirt1 rescues this defect in vitro and in vivo.…
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…Since TORC1 promotes interaction of CREB with TAF4 3, and the fact that TAF4 has been previously implicated in CREB transcription in HD20, it is also possible that interference of mutant HTT with TAF4 function contributes to transcriptional repression of BDNF gene in HD.…
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…Since mutant HTT partially inhibits Sirt1 deacetylase activity (Jiang et al.), it is not surprising that multiple substrates of Sirt1 exhibited increased acetylation in HD models.…
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…For example, in worms overexpressing Sir2 (ortholog of human Sirt1), HTT-induced neurodegeneration is suppressed, whereas overexpression in fly model of HD confers no significant protection 4,5.…
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…Previous studies demonstrated that wild-type HTT upregulates transcription of the BDNF gene by sequestrating the neuron-restrictive silencing factor (NRSF) in the cytoplasm, suggesting that wild-type HTT function plays an important protective role in the pathogenesis of HD 14,21.…
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Sirt1, a NAD-dependent protein deacetylase, has emerged as a key regulator of mammalian transcription in response to cellular metabolic status and stress. Here we show that Sirt1 has a neuroprotective role in models of Huntington's disease, an inherited neurodegenerative disorder caused by a glutamine repeat expansion in huntingtin protein (HTT). Brain-specific knockout of Sirt1 results in exacerbation of brain pathology in a mouse model of Huntington's disease, whereas overexpression of Sirt1 improves survival, neuropathology and the expression of brain-derived neurotrophic factor (BDNF) in Huntington's disease mice. We show that Sirt1 deacetylase activity directly targets neurons to mediate neuroprotection from mutant HTT. The neuroprotective effect of Sirt1 requires the presence of CREB-regulated transcription coactivator 1 (TORC1), a brain-specific modulator of CREB activity. We show that under normal conditions, Sirt1 deacetylates and activates TORC1 by promoting its dephosphorylation and its interaction with CREB. We identified BDNF as a key target of Sirt1 and TORC1 transcriptional activity in both normal and Huntington's disease neurons. Mutant HTT interferes with the TORC1-CREB interaction to repress BDNF transcription, and Sirt1 rescues this defect in vitro and in vivo. These studies suggest a key role for Sirt1 in transcriptional networks in both the normal and Huntington's disease brain and offer an opportunity for therapeutic development.
Also flagged:Sirt1neurodegenerative disorderdeacetylaseHDpolyglutaminepathogenesis
Journal Article2011-12-18✓ 5 SnippetsJiang M, Wang J, Fu J, Du L, Jeong H, West T, Xiang L, Peng Q, Hou Z, Cai H, Seredenina T, Arbez N, Zhu S, Sommers K, Qian J, Zhang J, Zhang J, Mori S, Yang XW, Tamashiro KL, Aja S, Moran TH, Luthi-Carter R, Martin B, Maudsley S, Mattson MP, Cichewicz RH, Ross CA, Holtzman DM, Krainc D, Duan W.
In-Text Gene Mentions
Abstract)
…Overexpression of Sirt1 improves motor function, reduces brain atrophy and attenuates mutant-HTT-mediated metabolic abnormalities in Huntington's disease mice.…
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…Further mechanistic studies suggested that Sirt1 prevents the mutant-HTT-induced decline in brain-derived neurotrophic factor (BDNF) concentrations and the signaling of its receptor, TrkB, and restores dopamine- and cAMP-regulated phosphoprotein, 32 kDa (DARPP32) concentrations in the striatum.…
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…Huntington's disease is a fatal neurodegenerative disorder caused by an expanded polyglutamine repeat in huntingtin (HTT) protein.…
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…repeat in huntingtin (HTT) protein.…
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…neurons against mutantHtttoxicity, whereas reduction…
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Huntington's disease is a fatal neurodegenerative disorder caused by an expanded polyglutamine repeat in huntingtin (HTT) protein. We previously showed that calorie restriction ameliorated Huntington's disease pathogenesis and slowed disease progression in mice that model Huntington's disease (Huntington's disease mice). We now report that overexpression of sirtuin 1 (Sirt1), a mediator of the beneficial metabolic effects of calorie restriction, protects neurons against mutant HTT toxicity, whereas reduction of Sirt1 exacerbates mutant HTT toxicity. Overexpression of Sirt1 improves motor function, reduces brain atrophy and attenuates mutant-HTT-mediated metabolic abnormalities in Huntington's disease mice. Further mechanistic studies suggested that Sirt1 prevents the mutant-HTT-induced decline in brain-derived neurotrophic factor (BDNF) concentrations and the signaling of its receptor, TrkB, and restores dopamine- and cAMP-regulated phosphoprotein, 32 kDa (DARPP32) concentrations in the striatum. Sirt1 deacetylase activity is required for Sirt1-mediated neuroprotection in Huntington's disease cell models. Notably, we show that mutant HTT interacts with Sirt1 and inhibits Sirt1 deacetylase activity, which results in hyperacetylation of Sirt1 substrates such as forkhead box O3A (Foxo3a), thereby inhibiting its pro-survival function. Overexpression of Sirt1 counteracts the mutant-HTT-induced deacetylase deficit, enhances the deacetylation of Foxo3a and facilitates cell survival. These findings show a neuroprotective role for Sirt1 in mammalian Huntington's disease models and open new avenues for the development of neuroprotective strategies in Huntington's disease.
Also flagged:anaphasechromosomemitosistumorchromosomescancers
Journal Article2011-12-17✓ 2 SnippetsSamoshkin A, Dulev S, Loukinov D, Rosenfeld JA, Strunnikov AV.
In-Text Gene Mentions
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…Condensindysfunction in human…
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…Condensincomplexes are essential…
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Condensin complexes are essential for chromosome condensation and segregation in mitosis, while condensin dysfunction, among other pathways leading to chromosomal bridging in mitosis, may play a role in tumor genomic instability, including recently discovered chromotripsis. To characterize potential double-strand breaks specifically occurring in late anaphase, human chromosomes depleted of condensin were analyzed by γ-H2AX ChIP followed by high-throughput sequencing (ChIP-seq). In condensin-depleted cells, the nonrepeated parts of the genome were shown to contain distinct γ-H2AX enrichment zones 75% of which overlapped with known hemizygous deletions in cancers. Furthermore, some tandemly repeated DNA sequences, analyzed separately from the rest of the genome, showed significant γ-H2AX enrichment in condensin-depleted anaphases. The most commonly occurring targets of such enrichment included simple repeats, centromeric satellites, and rDNA. The two latter categories indicate that acrocentric human chromosomes are especially susceptible to breaks upon condensin deficiency. The genomic regions that are specifically destabilized upon condensin dysfunction may constitute a condensin-specific chromosome destabilization pattern.
Transglutaminase 2 (TG2) is a Ca(2+)-dependent enzyme able to catalyze the formation of ε(γ-glutamyl)-lysine crosslinks between polypeptides, resulting in high molecular mass multimers. We have developed a bioorthogonal chemical method for the labeling of TG2 glutamine-donor proteins. As amine-donor substrates we used a set of azide- and alkyne-containing primary alkylamines that allow, after being crosslinked to glutamine-donor proteins, specific labeling of these proteins via the azide-alkyne cycloaddition. We demonstrate that these azide- and alkyne-functionalized TG2 substrates are cell permeable and suitable for specific labeling of TG2 glutamine-donor substrates in HeLa and Movas cells. Both the Cu(I)-catalyzed and strain promoted azide-alkyne cycloaddition proved applicable for subsequent derivatization of the TG2 substrate proteins with the desired probe. This new method for labeling TG2 substrate proteins introduces flexibility in the detection and/or purification of crosslinked proteins, allowing differential labeling of cellular proteins.
Also flagged:gene expressionacute lymphoblastic leukemiaALLTP53interferonleukemias
Journal Article2011-12-16No SnippetsNordlund J, Kiialainen A, Karlberg O, Berglund EC, Göransson-Kultima H, Sønderkær M, Nielsen KL, Gustafsson MG, Behrendtz M, Forestier E, Perkkiö M, Söderhäll S, Lönnerholm G, Syvänen AC.
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We determined the genome-wide digital gene expression (DGE) profiles of primary acute lymphoblastic leukemia (ALL) cells from 21 patients taking advantage of 'second-generation' sequencing technology. Patients included in this study represent four cytogenetically distinct subtypes of B-cell precursor (BCP) ALL and T-cell lineage ALL (T-ALL). The robustness of DGE combined with supervised classification by nearest shrunken centroids (NSC) was validated experimentally and by comparison with published expression data for large sets of ALL samples. Genes that were differentially expressed between BCP ALL subtypes were enriched to distinct signaling pathways with dic(9;20) enriched to TP53 signaling, t(9;22) to interferon signaling, as well as high hyperdiploidy and t(12;21) to apoptosis signaling. We also observed antisense tags expressed from the non-coding strand of ~50% of annotated genes, many of which were expressed in a subtype-specific pattern. Antisense tags from 17 gene regions unambiguously discriminated between the BCP ALL and T-ALL subtypes, and antisense tags from 76 gene regions discriminated between the 4 BCP subtypes. We observed a significant overlap of gene regions with alternative polyadenylation and antisense transcription (P<1 × 10(-15)). Our study using DGE profiling provided new insights into the RNA expression patterns in ALL cells.
Also flagged:Netrin-4lamininangiogenesiskinasesprotein kinaseprotein kinases
Journal Article2011-12-16✓ 1 SnippetLambert E, Coissieux MM, Laudet V, Mehlen P.
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Netrins form a heterogeneous family of laminin-related molecules with multifunctional activities. Netrin-4, the most distant member of this family, is related to the laminin β chain and has recently been proposed to play an important role in embryonic and pathological angiogenesis. However, the data reported so far lead to the apparently contradictory conclusions supporting Netrin-4 as either a pro- or an anti-angiogenic factor. To elucidate this controversy, Netrin-4 was analyzed for a vascular activity in both cell-based models (human umbilical vein endothelial cells and human umbilical artery endothelial cells) and two zebrafish models: the wild-type AB/Tü strain and the transgenic Tg(fli1a:EGFP)(y1) strain. We show that Netrin-4 is expressed in endothelial cells and in the zebrafish vascular system. We also show evidence that Netrin-4 activates various kinases and induces various biological effects directly linked to angiogenesis in vitro. Using a morpholinos strategy, we demonstrate that Netrin-4 expression is crucial for zebrafish vessel formation and that a blood vessel formation defect induced by netrin-4 morpholinos can be partially rescued through drug delivery leading to protein kinase activation. Together these data underscore the crucial role of Netrin-4 in blood vessel formation and the involvement of protein kinases activation in Netrin-4-induced biological effects related to vascular development.
Also flagged:metforminDiabetesPPARGTMEM18obesityLYPLAL1
Journal Article2011-12-16✓ 5 SnippetsDelahanty LM, Pan Q, Jablonski KA, Watson KE, McCaffery JM, Shuldiner A, Kahn SE, Knowler WC, Florez JC, Franks PW, Diabetes Prevention Program Research Group.
<h4>Objective</h4>We tested genetic associations with weight loss and weight regain in the Diabetes Prevention Program, a randomized controlled trial of weight loss-inducing interventions (lifestyle and metformin) versus placebo.<h4>Research design and methods</h4>Sixteen obesity-predisposing single nucleotide polymorphisms (SNPs) were tested for association with short-term (baseline to 6 months) and long-term (baseline to 2 years) weight loss and weight regain (6 months to study end).<h4>Results</h4>Irrespective of treatment, the Ala12 allele at PPARG associated with short- and long-term weight loss (-0.63 and -0.93 kg/allele, P ≤ 0.005, respectively). Gene-treatment interactions were observed for short-term (LYPLAL1 rs2605100, P(lifestyle*SNP) = 0.032; GNPDA2 rs10938397, P(lifestyle*SNP) = 0.016; MTCH2 rs10838738, P(lifestyle*SNP) = 0.022) and long-term (NEGR1 rs2815752, P(metformin*SNP) = 0.028; FTO rs9939609, P(lifestyle*SNP) = 0.044) weight loss. Three of 16 SNPs were associated with weight regain (NEGR1 rs2815752, BDNF rs6265, PPARG rs1801282), irrespective of treatment. TMEM18 rs6548238 and KTCD15 rs29941 showed treatment-specific effects (P(lifestyle*SNP) < 0.05).<h4>Conclusions</h4>Genetic information may help identify people who require additional support to maintain reduced weight after clinical intervention.
<h4>Background</h4>Iron metabolism during pregnancy maintains fetal iron levels at the expense of the mother. The mechanism behind this regulation is still not clear despite recent advances. Here we examine the role of maternal and fetal Hfe, its downstream signaling molecule, hepcidin and dietary iron in the regulation of placental iron transfer.<h4>Design and methods</h4>Hfe wild-type, knockout and heterozygote dams were fed iron deficient (12.5 ppm), adequate (50 ppm) and replete (150 ppm) iron diets and mated with heterozygote males to produce pups of all genotypes. Dams and pups were sacrificed at Day 18 of gestation; serum, placenta, body and liver iron parameters were measured. Protein and mRNA levels of various iron transporter genes were determined in duodenum, liver and placenta by Western blotting and real time PCR.<h4>Results</h4>Maternal liver iron levels were dependent on both dietary iron intake and Hfe genotype. Increasing iron levels in the maternal diet resulted in increased total iron in the fetus, primarily in the liver. However, fetuses of Hfe-knockout mothers showed further elevation of liver iron levels, concomitant with elevated expression of Tfr1, Dmt1 and Fpn in the placenta. Hfe-knockout fetuses that express low levels of liver hepcidin accumulated more iron in their liver than wild-type fetuses due to increased ferroportin levels in the placenta.<h4>Conclusions</h4>Maternal and fetal status, as well as dietary iron, is important in regulating iron transfer across placenta. Maternal Hfe regulates iron transfer by altering gene expression in the placenta. Fetal Hfe is important in regulating placental iron transfer by modulating fetal liver hepcidin expression.
<h4>Background</h4>In transfusional siderosis, the iron binding capacity of plasma transferrin is often surpassed, with concomitant generation of non-transferrin-bound iron. Although implicated in tissue siderosis, non-transferrin-bound iron modes of cell ingress remain undefined, largely because of its variable composition and association with macromolecules. Using fluorescent tracing of labile iron in endosomal vesicles and cytosol, we examined the hypothesis that non-transferrin-bound iron fractions detected in iron overloaded patients enter cells via bulk endocytosis.<h4>Design and methods</h4>Fluorescence microscopy and flow cytometry served as analytical tools for tracing non-transferrin-bound iron entry into endosomes with the redox-reactive macromolecular probe Oxyburst-Green and into the cytosol with cell-laden calcein green and calcein blue. Non-transferrin-bound iron-containing media were from sera of polytransfused thalassemia major patients and model iron substances detected in thalassemia major sera; cell models were cultured macrophages, and cardiac myoblasts and myocytes.<h4>Results</h4>Exposure of cells to ferric citrate together with albumin, or to non-transferrin-bound iron-containing sera from thalassemia major patients caused an increase in labile iron content of endosomes and cytosol in macrophages and cardiac cells. This increase was more striking in macrophages, but in both cell types was largely reduced by co-exposure to non-transferrin-bound iron-containing media with non-penetrating iron chelators or apo-transferrin, or by treatment with inhibitors of endocytosis. Endosomal iron accumulation traced with calcein-green was proportional to input non-transferrin-bound iron levels (r(2) = 0.61) and also preventable by pre-chelation.<h4>Conclusions</h4>Our studies indicate that macromolecule-associated non-transferrin-bound iron can initially gain access into various cells via endocytic pathways, followed by iron translocation to the cytosol. Endocytic uptake of plasma non-transferrin-bound iron is a possible mechanism that can contribute to iron loading of cell types engaged in bulk/adsorptive endocytosis, highlighting the importance of its prevention by iron chelation.
In rats and mice, ascending and descending axons from neurons producing melanin-concentrating hormone (MCH) reach the cerebral cortex and spinal cord. However, these ascending and descending projections originate from distinct sub-populations expressing or not "Cocaine-and-Amphetamine-Regulated-Transcript" (CART) peptide. Using a BrdU approach, MCH cell bodies are among the very first generated in the hypothalamus, within a longitudinal cell cord made of earliest delaminating neuroblasts in the diencephalon and extending from the chiasmatic region to the ventral midbrain. This region also specifically expresses the regulatory genes Sonic hedgehog (Shh) and Nkx2.2. First MCH axons run through the tractus postopticus (tpoc) which gathers pioneer axons from the cell cord and courses parallel to the Shh/Nkx2.2 expression domain. Subsequently generated MCH neurons and ascending MCH axons differentiate while neurogenesis and mantle layer differentiation are generalized in the prosencephalon, including telencephalon. Ascending MCH axons follow dopaminergic axons of the mesotelencephalic tract, both being an initial component of the medial forebrain bundle (mfb). Netrin1 and Slit2 proteins that are involved in the establishment of the tpoc and mfb, respectively attract or repulse MCH axons.We conclude that first generated MCH neurons develop in a diencephalic segment of a longitudinal Shh/Nkx2.2 domain. This region can be seen as a prosencephalic segment of a medial neurogenic column extending from the chiasmatic region through the ventral neural tube. However, as the telencephalon expends, it exerts a trophic action and the mfb expands, inducing a switch in the longitudinal axial organization of the prosencephalon.
Also flagged:tPAedaravonetransient cerebral ischemiatissue plasminogen activatorchondroitinsulfate
Journal Article2011-12-16✓ 3 SnippetsDeguchi K, Miyazaki K, Tian F, Liu N, Liu W, Kawai H, Omote Y, Kono S, Yunoki T, Deguchi S, Abe K.
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…Immunohistochemistry and western blot analyses indicated that protein expression of neurocan, Sema3A, Nogo-R, GAP43, and DCC was decreased with tPA, but recovered with edaravone.…
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…in colorectal cancer,DCC).…
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…Nogo-R, GAP43, andDCCwas decreased with…
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Changes in expression of neurorepair and neuroregenerative factors were examined after transient cerebral ischemia in relation to the effects of tissue plasminogen activator (tPA) and the free radical scavenger edaravone. Physiological saline or edaravone was injected twice during 90 min of transient middle cerebral artery occlusion (tMCAO) in rats, followed by the same saline or tPA at reperfusion. Sizes of the infarct and protein factors relating to neurorepair and neuroregeneration were examined at 4d after tMCAO. The protein factors examined were: a chondroitin sulfate proteoglycan neurocan, semaphorin type 3A (Sema3A), a myelin-associated glycoprotein receptor (Nogo receptor, Nogo-R), a synaptic regenerative factor (growth associated protein-43, GAP43), and a chemotropic factor netrin receptor (deleted in colorectal cancer, DCC). Two groups treated by edaravone only or edaravone plus tPA showed a reduction in infarct volume compared to the two groups treated by vehicle only or vehicle plus tPA. Immunohistochemistry and western blot analyses indicated that protein expression of neurocan, Sema3A, Nogo-R, GAP43, and DCC was decreased with tPA, but recovered with edaravone. Additive edaravone prevented the reductions of these five proteins induced by tPA. The present study demonstrates for the first time that exogenous tPA reduced protein factors involved in inhibiting and promoting axonal growth, but that edaravone ameliorated such damage in brain repair after acute ischemia.
Also flagged:epithelial-mesenchymal-transitionp53tumortranscription factor-epithelial-transitionSLUG
Journal Article2011-12-15✓ 1 SnippetSiemens H, Jackstadt R, Hünten S, Kaller M, Menssen A, Götz U, Hermeking H.
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…BMI1, CD44, CD133,OLFM4and c-MYC.…
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Recently, the inhibition of epithelial-mesenchymal-transition (EMT) by p53 has been described as a new mode of tumor suppression which presumably prevents metastasis. Here we report that activation of p53 down-regulates the EMT-inducing transcription factor SNAIL via induction of the miR-34a/b/c genes. Suppression of miR-34a/b/c caused up-regulation of SNAIL and cells displayed EMT markers and related features, as enhanced migration and invasion. Ectopic miR-34a induced mesenchymal-epithelial-transition (MET) and down-regulation of SNAIL, which was mediated by a conserved miR-34a/b/c seed-matching sequence in the SNAIL 3'-UTR. miR-34a also down-regulated SLUG and ZEB1, as well as the stemness factors BMI1, CD44, CD133, OLFM4 and c-MYC. Conversely, the transcription factors SNAIL and ZEB1 bound to E-boxes in the miR-34a/b/c promoters, thereby repressing miR-34a and miR-34b/c expression. Since ectopic miR-34a prevented TGF-β-induced EMT, the repression of miR-34 genes by SNAIL and related factors is part of the EMT program. In conclusion, the frequent inactivation of p53 and/or miR-34a/b/c found in cancer may shift the equilibrium of these reciprocal regulations towards the mesenchymal state and thereby lock cells in a metastatic state.
Also flagged:OX40LpathogenesisPulmonary arterial hypertensionPHimmunological disordersOX40
Journal Article2011-12-15✓ 1 SnippetRabieyousefi M, Soroosh P, Satoh K, Date F, Ishii N, Yamashita M, Oka M, McMurtry IF, Shimokawa H, Nose M, Sugamura K, Ono M.
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…of OX40 (OX40L:TNFSF4, CD134L) is mainly…
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<h4>Background</h4>Pulmonary hypertension (PH) refers to a spectrum of diseases with elevated pulmonary artery pressure. Pulmonary arterial hypertension (PAH) is a disease category that clinically presents with severe PH and that is histopathologically characterized by the occlusion of pulmonary arterioles, medial muscular hypertrophy, and/or intimal fibrosis. PAH occurs with a secondary as well as a primary onset. Secondary PAH is known to be complicated with immunological disorders. The aim of the present study is to histopathologically and genetically characterize a new animal model of PAH and clarify the role of OX40 ligand in the pathogenesis of PAH.<h4>Results</h4>Spontaneous onset of PAH was stably identified in mice with immune abnormality because of overexpression of the tumor necrosis factor (TNF) family molecule OX40 ligand (OX40L). Histopathological and physical examinations revealed the onset of PAH-like disorders in the C57BL/6 (B6) strain of OX40L transgenic mice (B6.TgL). Comparative analysis performed using different strains of transgenic mice showed that this onset depends on the presence of OX40L in the B6 genetic background. Genetic analyses demonstrated a susceptibility locus of a B6 allele to this onset on chromosome 5. Immunological analyses revealed that the excessive OX40 signals in TgL mice attenuates expansion of regulatory T cells the B6 genetic background, suggesting an impact of the B6 genetic background on the differentiation of regulatory T cells.<h4>Conclusion</h4>Present findings suggest a role for the OX40L-derived immune response and epistatic genetic effect in immune-mediated pathogenesis of PAH.
Also flagged:telomerenitric oxideoxygenOAmitochondriamitochondrial
Journal Article2011-12-15No SnippetsFernández-Moreno M, Tamayo M, Soto-Hermida A, Mosquera A, Oreiro N, Fernández-López C, Fernández JL, Rego-Pérez I, Blanco FJ.
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<h4>Background</h4>Oxidative stress due to the overproduction of nitric oxide (NO) and other oxygen reactive species (ROS), play a main role in the initiation and progression of the OA disease and leads to the degeneration of mitochondria. Therefore, the goal of this work is to describe the difference in telomere length of peripheral blood leukocytes (PBLs) and Nitric Oxide (NO) production between mitochondrial DNA (mtDNA) haplogroup J and non-J carriers, as indirect approaches of oxidative stress.<h4>Methods</h4>The telomere length of PBL was analyzed in DNA samples from 166 healthy controls (114 J and 52 non-J) and 79 OA patients (41 J and 38 non-J) by means of a validated qPCR method. The NO production was assessed in 7 carriers of the haplogroup J and 27 non-J carriers, by means of the colorimetric reaction of the Griess reagent in supernatants of cultured chondrocytes. Inducible nitric oxide synthase (iNOS) mRNA from these samples was analyzed by qPCR. Appropiated statistical analyses were performed<h4>Results</h4>Carriers of the haplogroup J showed a significantly longer telomere length of PBLs than non-J carriers, regardless of age, gender and diagnosis (p = 0.025). Cultured chondrocytes carrying the mtDNA haplogroup J also showed a lower NO production than non-J carriers (p = 0.043). No significant correlations between age and telomore length of PBLs were detected neither for carriers of the haplogroup J nor for non-J carriers. A strong positive correlation between NO production and iNOS expression was also observed (correlation coefficient = 0.791, p < 0.001).<h4>Conclusion</h4>The protective effect of the mtDNA haplogroup J in the OA disease arise from a lower oxidative stress in carriers of this haplogroup, since this haplogroup is related to lower NO production and hence longer telomere length of PBLs too.
Also flagged:pancreatic ductal adenocarcinomascancersmethylationmethylation-specifichypermethylationMucinous Neoplasms
Journal Article2011-12-15✓ 2 SnippetsHong SM, Omura N, Vincent A, Li A, Knight S, Yu J, Hruban RH, Goggins M.
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<h4>Purpose</h4>Intraductal papillary mucinous neoplasms (IPMN) are precursors to infiltrating pancreatic ductal adenocarcinomas. Widespread epigenetic alterations are characteristic of many cancers, yet few studies have systematically analyzed epigenetic alterations of neoplastic precursors. Our goal was to conduct genome-wide CpG island methylation profiling to identify aberrantly methylated loci in IPMNs.<h4>Experimental design</h4>We compared the CpG island methylation profiles of six IPMNs to normal primary pancreatic duct samples using methylation CpG island amplification (MCA) and Agilent CpG island microarray (MCAM) analysis. When selected 13 genes identified as differentially methylated by MCAM for methylation-specific PCR (MSP) analysis in an independent set of IPMNs and normal pancreas samples and conducted expression analysis of selected genes.<h4>Results</h4>We identified 2,259 loci as differentially methylated in at least one of six IPMNs including 245 genes hypermethylated in IPMNs with high-grade dysplasia compared with normal pancreatic duct samples. Eleven of 13 genes evaluated by MSP were more commonly methylated in 61 IPMNs than in 43 normal pancreas samples. Several genes (BNIP3, PTCHD2, SOX17, NXPH1, EBF3) were significantly more likely to be methylated in IPMNs with high-grade than with low-grade dysplasia. One gene, SOX17, showed loss of protein expression by immunohistochemistry in 22% (19 of 88) of IPMNs. The most specific marker, BNIP3, was not methylated in any IPMNs with low-grade dysplasia or in normal pancreas samples.<h4>Conclusions</h4>IPMNs undergo extensive aberrant CpG island hypermethylation. The detection of genes selectively methylated in high-grade IPMNs such as BNIP3 may have use in the clinical evaluation of IPMNs.
…Didymin induces apoptosis by inhibiting N-Myc and upregulating RKIP in neuroblastoma.…
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Neuroblastomas arise from the neural crest cells and represent the most common solid tumors outside the nervous system in children. The amplification of N-Myc plays a primary role in the pathogenesis of neuroblastomas, whereas acquired mutations of p53 lead to refractory and relapsed cases of neuroblastomas. In this regard, dietary compounds which can target N-Myc and exert anticancer effects independent of p53 status acquire significance in the management of neuroblastomas. Hence, we investigated the anticancer properties of the flavonoid didymin in neuroblastomas. Didymin effectively inhibited proliferation and induced apoptosis irrespective of p53 status in neuroblastomas. Didymin downregulated phosphoinositide 3-kinase, pAkt, Akt, vimentin, and upregulated RKIP levels. Didymin induced G(2)/M arrest along with decreasing the levels of cyclin D1, CDK4, and cyclin B1. Importantly, didymin inhibited N-Myc as confirmed at protein, mRNA, and transcriptional level by promoter-reporter assays. High-performance liquid chromatography analysis of didymin-treated (2 mg/kg b.w.) mice serum revealed effective oral absorption with free didymin concentration of 2.1 μmol/L. Further in vivo mice xenograft studies revealed that didymin-treated (2 mg/kg b.w.) animals had significant reductions in tumors size compared with controls. Didymin strongly inhibited the proliferation (Ki67) and angiogenesis (CD31) markers, as well as N-Myc expression, as revealed by the histopathologic examination of paraffin-embedded section of resected tumors. Collectively, our in vitro and in vivo studies elucidated the anticancer properties and mechanisms of action of a novel, orally active, and palatable flavonoid didymin, which makes it a potential new approach for neuroblastoma therapy (NANT) to target pediatric neuroblastomas.
Also flagged:hemophiliaDengueperfluorocarbonsoxygenHemoglobinmyocardial infarction
Journal Article2011-12-15No SnippetsMigliaccio AR, Masselli E, Varricchio L, Whitsett C.
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Blood transfusion is indispensable for modern medicine. In developed countries, the blood supply is adequate and safe but blood for alloimmunized patients is often unavailable. Concerns are increasing that donations may become inadequate in the future as the population ages prompting a search for alternative transfusion products. Improvements in culture conditions and proof-of-principle studies in animal models have suggested that ex-vivo expanded red cells may represent such a product. Compared to other cell therapies transfusion poses the unique challenge of requiring great cell doses (2.5×10(12) cells vs 10(7) cells). Although production of such cell numbers is theoretically possible, current technologies generate red cells in numbers sufficient only for safety studies. It is conceived that by the time these studies will be completed, technical barriers to mass cell production will have been eliminated making transfusion with ex-vivo generated red cells a reality.
Also flagged:γ-secretasepolycystin-1TCFCHOPADPKDcarboxy
Journal Article2011-12-15✓ 1 SnippetMerrick D, Chapin H, Baggs JE, Yu Z, Somlo S, Sun Z, Hogenesch JB, Caplan MJ.
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Mutations in Pkd1, encoding polycystin-1 (PC1), cause autosomal-dominant polycystic kidney disease (ADPKD). We show that the carboxy-terminal tail (CTT) of PC1 is released by γ-secretase-mediated cleavage and regulates the Wnt and CHOP pathways by binding the transcription factors TCF and CHOP, disrupting their interaction with the common transcriptional coactivator p300. Loss of PC1 causes increased proliferation and apoptosis, while reintroducing PC1-CTT into cultured Pkd1 null cells reestablishes normal growth rate, suppresses apoptosis, and prevents cyst formation. Inhibition of γ-secretase activity impairs the ability of PC1 to suppress growth and apoptosis and leads to cyst formation in cultured renal epithelial cells. Expression of the PC1-CTT is sufficient to rescue the dorsal body curvature phenotype in zebrafish embryos resulting from either γ-secretase inhibition or suppression of Pkd1 expression. Thus, γ-secretase-dependent release of the PC1-CTT creates a protein fragment whose expression is sufficient to suppress ADPKD-related phenotypes in vitro and in vivo.
The microRNA miR-451 is downregulated in gliomas, this has been suggested by several different research groups and is consistent with our data. Our previous study also confirmed that miR-451 has a repressive role in glioma by inhibiting cell growth, proliferation and by inducing cell apoptosis. In the present study, we identified a target gene of miR-451 in human glioma and investigated the mechanism for the glioma suppressive effect of miR-451 functions. Expression of miR-451 in gliomas was identified by quantitative real-time PCR and fluorescence in situ hybridization. Human glioma cell lines (U251, U87, LN229 and A172) were transfected with miR-451 mimics to restore miR-451 expression. The tumor suppressive effects of miR-451 were further verified by subcutaneous assays in nude mice, in addition to our previous in vitro data. A candidate target gene was tested by Western blotting and luciferase reporter assays. Some PI3K/AKT pathway factors were tested by Western blotting. We found that miR-451 expression was downregulated in glioma samples and was inversely correlated with WHO grades of gliomas. In vivo assays confirmed that miR-451 had tumor suppressive traits. CAB39-3'UTR luciferase reporter assay confirmed CAB39 as a direct target gene of miR-451. Significant alterations in the expression of PI3K/AKT pathway factors were observed by Western blot assays. We conclude that miR-451 represses glioma in vitro and in vivo, likely through targeting CAB39 directly and inhibiting the PI3K/AKT pathway indirectly.
Also flagged:glioblastomasglioblastomaGBMcyclin ETGF-βCDC25B
Journal Article2011-12-15✓ 2 SnippetsJung Y, Joo KM, Seong DH, Choi YL, Kong DS, Kim Y, Kim MH, Jin J, Suh YL, Seol HJ, Shin CS, Lee JI, Kim JH, Song SY, Nam DH.
A set of proteins reflecting the prognosis of patients have clinical significance since they could be utilized as predictive biomarkers and/or potential therapeutic targets. With the aim of finding novel diagnostic and prognostic markers for glioblastoma (GBM), a tissue microarray (TMA) library consisting of 62 GBMs and 28 GBM-associated normal spots was constructed. Immunohistochemistry against 78 GBM-associated proteins was performed. Expression levels of each protein for each patient were analyzed using an image analysis program and converted to H-score [summation of the intensity grade of staining (0-3) multiplied by the percentage of positive cells corresponding to each grade]. Based on H-score and hierarchical clustering methods, we divided the GBMs into two groups (n=19 and 37) that had significantly different survival lengths (p<0.05). In the two groups, expression of nine proteins (survivin, cyclin E, DCC, TGF-β, CDC25B, histone H1, p-EGFR, p-VEGFR2/3, p16) was significantly changed (q<0.05). Prognosis-predicting potential of these proteins were validated with another independent library of 82 GBM TMAs and a public GBM DNA microarray dataset. In addition, we determined 32 aberrant or mislocalized subcellular protein expression patterns in GBMs compared with relatively normal brain tissues, which could be useful for diagnostic biomarkers of GBM. We therefore suggest that these proteins can be used as predictive biomarkers and/or potential therapeutic targets for GBM.
Also flagged:memantinePDNMDA receptorsglomerular filtrationrenal impairmentHD
Journal Article2011-12-15✓ 2 SnippetsBeconi MG, Howland D, Park L, Lyons K, Giuliano J, Dominguez C, Munoz-Sanjuan I, Pacifici R.
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…In addition, low- (but not high-) dose memantine resulted in decreased striatal levels of Rhes protein, which would be predicted to have beneficial effects by regulating mutant HTT aggregation and clearance.…
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…While low-dose memantine preserved the TRiC dependent pathway, high-dose memantine was found to decrease HTT aggregate formation and TCP-1 expression levels [9].…
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To evaluate the potential of memantine as a therapeutic agent for Huntington's disease (HD) we have undertaken a series of in vitro, ex vivo and whole animal studies to characterize its pharmacokinetics (PK) and pharmacodynamics (PD) in rats and mice. Results from these studies will enable determination of memantine exposures needed to engage the related functional PD marker and help predict the dose regimen for clinical trials to test its proposed mechanism of action; the selective blockade of extrasynaptic, but not synaptic, NMDA receptors. The studies reported here describe the PK of memantine in rats and mice at low (1 mg/kg) and high (10 mg/kg) doses. Our studies indicate that the clearance mechanisms of memantine in rats and mice are different from those in human, and that clearance needs to be taken into account when extrapolating to the human. In rats only, there is a significant metabolic contribution to memantine clearance at lower dose levels. While memantine is primarily cleared renally in all three species, the proportion of total systemic clearance above the glomerular filtration rate (GFR) is much higher in rats and mice (~13, 4.5, and 1.4 times higher than GFR in rats, mice, and humans, respectively), suggesting that the contribution of active transport to memantine elimination in rats and mice is more significant than in the human. In rats and mice, memantine had a short half-life (<4 h) and steep Cmax/Cmin ratios (>100). In the human, the half-life of memantine was reported to be very long (60-80 h) with a Cmax/Cmin ratio at steady state concentrations of ~1.5. A small change in the clearance of memantine - for example due to renal impairment or competition for the elimination pathway with a co-administered drug - will likely affect exposure and, therefore, the selectivity of memantine on NMDA receptors . The PK differences observed between these species demonstrate that the PK in mice and rats cannot be directly extrapolated to the human. Further, the relationship between the plasma concentration (and therefore dose) needed to elicit a mechanism-related in vivo functional effect (PD readout) while maintaining the selectivity of the extrasynaptic blockade of the NMDA receptors needs to be established before clinical trials can be appropriately planned.
Also flagged:gene expressionsepsispolymicrobial sepsisinflammatory responseinfectionsynthesis
Journal Article2011-12-15✓ 2 SnippetsYang Q, Mattick JS, Mattick JS, Orman MA, Nguyen TT, Ierapetritou MG, Berthiaume F, Androulakis IP.
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<h4>Background</h4>Sepsis remains a major clinical challenge in intensive care units. The difficulty in developing new and more effective treatments for sepsis exemplifies our incomplete understanding of the underlying pathophysiology of it. One of the more widely used rodent models for studying polymicrobial sepsis is cecal ligation and puncture (CLP). While a number of CLP studies investigated the ensuing systemic inflammatory response, they usually focus on a single time point post-CLP and therefore fail to describe the dynamics of the response. Furthermore, previous studies mostly use surgery without infection (herein referred to as sham CLP, SCLP) as a control for the CLP model, however, SCLP represents an aseptic injurious event that also stimulates a systemic inflammatory response. Thus, there is a need to better understand the dynamics and expression patterns of both injury- and sepsis-induced gene expression alterations to identify potential regulatory targets. In this direction, we characterized the response of the liver within the first 24 h in a rat model of SCLP and CLP using a time series of microarray gene expression data.<h4>Methods</h4>Rats were randomly divided into three groups: sham, SCLP, and CLP. Rats in SCLP group are subjected to laparotomy, cecal ligation, and puncture while those in CLP group are subjected to the similar procedures without cecal ligation and puncture. Animals were saline resuscitated and sacrificed at defined time points (0, 2, 4, 8, 16, and 24 h). Liver tissues were explanted and analyzed for their gene expression profiles using microarray technology. Unoperated animals (Sham) serve as negative controls. After identifying differentially expressed probesets between sham and SCLP or CLP conditions over time, the concatenated data sets corresponding to these differentially expressed probesets in sham and SCLP or CLP groups were combined and analyzed using a "consensus clustering" approach. Promoters of genes that share common characteristics were extracted and compared with gene batteries comprised of co-expressed genes to identify putatative transcription factors, which could be responsible for the co-regulation of those genes.<h4>Results</h4>The SCLP/CLP genes whose expression patterns significantly changed compared with sham over time were identified, clustered, and finally analyzed for pathway enrichment. Our results indicate that both CLP and SCLP triggered the activation of a proinflammatory response, enhanced synthesis of acute-phase proteins, increased metabolism, and tissue damage markers. Genes triggered by CLP, which can be directly linked to bacteria removal functions, were absent in SCLP injury. In addition, genes relevant to oxidative stress induced damage were unique to CLP injury, which may be due to the increased severity of CLP injury versus SCLP injury. Pathway enrichment identified pathways with similar functionality but different dynamics in the two injury models, indicating that the functions controlled by those pathways are under the influence of different transcription factors and regulatory mechanisms. Putatively identified transcription factors, notably including cAMP response element-binding (CREB), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and signal transducer and activator of transcription (STAT), were obtained through analysis of the promoter regions in the SCLP/CLP genes. Our results show that while transcription factors such as NF-κB, homeodomain transcription factor (HOMF), and GATA transcription factor (GATA) were common in both injuries for the IL-6 signaling pathway, there were many other transcription factors associated with that pathway which were unique to CLP, including forkhead (FKHD), hairy/enhancer of split family (HESF), and interferon regulatory factor family (IRFF). There were 17 transcription factors that were identified as important in at least two pathways in the CLP injury, but only seven transcription factors with that property in the SCLP injury. This also supports the hypothesis of unique regulatory modules that govern the pathways present in both the CLP and SCLP response.<h4>Conclusions</h4>By using microarrays to assess multiple genes in a high throughput manner, we demonstrate that an inflammatory response involving different dynamics and different genes is triggered by SCLP and CLP. From our analysis of the CLP data, the key characteristics of sepsis are a proinflammatory response, which drives hypermetabolism, immune cell activation, and damage from oxidative stress. This contrasts with SCLP, which triggers a modified inflammatory response leading to no immune cell activation, decreased detoxification potential, and hyper metabolism. Many of the identified transcription factors that drive the CLP-induced response are not found in the SCLP group, suggesting that SCLP and CLP induce different types of inflammatory responses via different regulatory pathways.
Journal Article2011-12-14✓ 1 SnippetRatziu V, Sheikh MY, Sanyal AJ, Lim JK, Conjeevaram H, Chalasani N, Abdelmalek M, Bakken A, Renou C, Palmer M, Levine RA, Bhandari BR, Cornpropst M, Liang W, King B, Mondou E, Rousseau FS, McHutchison J, Chojkier M.
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<h4>Unlabelled</h4>In nonalcoholic steatohepatitis (NASH), the extent of hepatocyte apoptosis correlates with disease severity. Reducing hepatocyte apoptosis with the selective caspase inhibitor GS-9450 has a potential for altering the course of the liver disease. In this phase 2, double-blind study, 124 subjects with biopsy-proven NASH were randomized to once-daily placebo or 1, 5, 10, or 40 mg GS-9450 for 4 weeks. Absolute and percent changes from baseline in ALT levels, AST levels, and caspase-3-cleaved cytokeratin (CK)-18 fragments at week 4 were assessed by an analysis of covariance model with adjustment for baseline values. In the 40-mg group, mean (SD) ALT decreased by 47 (43) U/L from baseline to week 4 (P < 0.0001 versus placebo), and the proportion of subjects with normal ALT increased from 0% to 35% at week 4. In the 40-mg group, mean AST decreased by 13 U/L from baseline (not significant), and the proportion with normal AST increased from 20% at baseline to 48% at week 4. By week 4, mean CK-18 fragment levels had decreased to 393 (723) U/L in the GS-9450 10-mg group and 125 (212) U/L in the 40-mg group, but these reductions were not statistically significant. No serious adverse events were reported during treatment, and the percentage of subjects with at least one treatment-emergent grade 3 or 4 laboratory abnormality ranged from 11.5% to 17% across the GS-9450 treatment groups versus 35% in the placebo group.<h4>Conclusion</h4>GS-9450 treatment induced significant reductions in ALT levels in NASH patients. Reductions in CK-18 fragment levels also occurred, although they were not statistically significant. At appropriate therapeutic indices, selective caspase inhibitors may be a promising treatment option in patients with NASH.
Also flagged:gene expressionischemic strokeISstrokeintegrin-liked kinasejunction
Journal Article2011-12-14No SnippetsTian Y, Stamova B, Jickling GC, Liu D, Ander BP, Bushnell C, Zhan X, Davis RR, Verro P, Pevec WC, Hedayati N, Dawson DL, Khoury J, Jauch EC, Pancioli A, Broderick JP, Sharp FR.
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This study examined the effects of gender on RNA expression after ischemic stroke (IS). RNA obtained from blood of IS patients (n=51; 153 samples at < or =3, 5, and 24 hours) and from matched controls (n=52) were processed on Affymetrix microarrays. Analyses of covariance for stroke versus control samples were performed separately for both genders and the regulated genes for females compared with males. In all, 242, 227, and 338 male-specific genes were regulated at < or =3, 5, and 24 hours after IS, respectively, of which 59 were regulated at all time points. Overall, 774, 3,437, and 571 female-specific stroke genes were regulated at < or =3, 5, and 24 hours, respectively, of which 152 were regulated at all time points. Male-specific stroke genes were associated with integrin, integrin-liked kinase, actin, tight junction, Wnt/β-catenin, RhoA, fibroblast growth factors (FGF), granzyme, and tumor necrosis factor receptor (TNFR)2 signaling. Female-specific stroke genes were associated with p53, high-mobility group box-1, hypoxia inducible factor (HIF)1α, interleukin (IL)1, IL6, IL12, IL18, acute-phase response, T-helper, macrophage, and estrogen signaling. Cell death signaling was overrepresented in both genders, although the molecules and pathways differed. Gender affects gene expression in the blood of IS patients, which likely implies gender differences in immune, inflammatory, and cell death responses to stroke.
Also flagged:tourette syndromeTSschizophreniaAutismneuropsychiatric syndromeshistamine receptor
Journal Article2011-12-14No SnippetsFernandez TV, Sanders SJ, Yurkiewicz IR, Ercan-Sencicek AG, Kim YS, Fishman DO, Raubeson MJ, Song Y, Yasuno K, Ho WS, Bilguvar K, Glessner J, Chu SH, Leckman JF, King RA, Gilbert DL, Heiman GA, Tischfield JA, Hoekstra PJ, Devlin B, Hakonarson H, Mane SM, Günel M, State MW.
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<h4>Background</h4>Studies of copy number variation (CNV) have characterized loci and molecular pathways in a range of neuropsychiatric conditions. We analyzed rare CNVs in Tourette syndrome (TS) to identify novel risk regions and relevant pathways, to evaluate burden of structural variation in cases versus controls, and to assess overlap of identified variations with those in other neuropsychiatric syndromes.<h4>Methods</h4>We conducted a case-control study of 460 individuals with TS, including 148 parent-child trios and 1131 controls. CNV analysis was undertaken using 370 K to 1 M probe arrays, and genotyping data were used to match cases and controls for ancestry. CNVs present in < 1% of the population were evaluated.<h4>Results</h4>While there was no significant increase in the number of de novo or transmitted rare CNVs in cases versus controls, pathway analysis using multiple algorithms showed enrichment of genes within histamine receptor (subtypes 1 and 2) signaling pathways (p = 5.8 × 10(-4) - 1.6 × 10(-2)), as well as axon guidance, cell adhesion, nervous system development, and synaptic structure and function processes. Genes mapping within rare CNVs in TS showed significant overlap with those previously identified in autism spectrum disorders but not intellectual disability or schizophrenia. Three large, likely pathogenic, de novo events were identified, including one disrupting multiple gamma-aminobutyric acid receptor genes.<h4>Conclusions</h4>We identify further evidence supporting recent findings regarding the involvement of histaminergic and gamma-aminobutyric acidergic mechanisms in the etiology of TS and show an overlap of rare CNVs in TS and autism spectrum disorders.
Also flagged:APLP1voltage-gated Ca-channelCa(v)2.Voltage gated calcium channelsresponse tomembrane
Journal Article2011-12-14No SnippetsRadhakrishnan K, Krieger A, Dibué M, Hescheler J, Schneider T.
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<h4>Background</h4>Voltage gated calcium channels (VGCCs) regulate cellular activity in response to membrane depolarization by altering calcium homeostasis. Because calcium is the most versatile second messenger, regulation of the amount of VGCCs at the plasma membrane is highly critical for several essential cellular processes. Among the different types of VGCCs, the Ca(v)2.3 calcium channel and its regulation mechanisms are least understood due to Ca(v)2.3's resistance to most pharmacological agents.<h4>Methods</h4>In order to study regulation and surface expression of Ca(v)2.3, a yeast two hybrid (Y2H) screen with the II-III loop of human Ca(v)2.3 as bait, was performed. APLP1, a member of the APP gene family and Rab5A, an endocytotic catalyst were identified as putative interaction partners. The interaction were confirmed by immunoprecipitation. To study the functional importance of the interaction, patch-clamp recordings in Ca(v)2.3 stably transfected HEK-293 cells (2C6) and surface biotin endocytosis assays were performed.<h4>Results</h4>We are able to show that the II-III loop of the Ca(v)2.3 calcium channel binds APLP1 and that this binding promotes internalization of the channel. In addition, Rab5A also binds to the same loop of the channel and exerts an inhibitory effect on APLP1 mediated channel internalization.<h4>Conclusions</h4>This study identifies a regulation mechanism of Ca(v)2.3's surface expression, which implicates APLP1 as a regulator of calcium homeostasis. Thus APLP1 may play a crucial role in neuropathological mechanisms, which involve modulation of surface expression of voltage-gated Ca(2+) channels.
Also flagged:GAPDHUbiquitin-conjugating enzyme E2Hsp40STOML2PPIApolypeptide
Journal Article2011-12-14No SnippetsKaakoush NO, Deshpande NP, Wilkins MR, Tan CG, Burgos-Portugal JA, Raftery MJ, Day AS, Lemberg DA, Mitchell H.
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Campylobacter concisus has garnered increasing attention due to its association with intestinal disease, thus, the pathogenic potential of strains isolated from different intestinal diseases was investigated. A method to isolate C. concisus was developed and the ability of eight strains from chronic and acute intestinal diseases to adhere to and invade intestinal epithelial cells was determined. Features associated with bacterial invasion were investigated using comparative genomic analyses and the effect of C. concisus on host protein expression was examined using proteomics. Our isolation method from intestinal biopsies resulted in the isolation of three C. concisus strains from children with Crohn's disease or chronic gastroenteritis. Four C. concisus strains from patients with chronic intestinal diseases can attach to and invade host cells using mechanisms such as chemoattraction to mucin, aggregation, flagellum-mediated attachment, "membrane ruffling", cell penetration and damage. C. concisus strains isolated from patients with chronic intestinal diseases have significantly higher invasive potential than those from acute intestinal diseases. Investigation of the cause of this increased pathogenic potential revealed a plasmid to be responsible. 78 and 47 proteins were upregulated and downregulated in cells infected with C. concisus, respectively. Functional analysis of these proteins showed that C. concisus infection regulated processes related to interleukin-12 production, proteasome activation and NF-κB activation. Infection with all eight C. concisus strains resulted in host cells producing high levels of interleukin-12, however, only strains capable of invading host cells resulted in interferon-γ production as confirmed by ELISA. These findings considerably support the emergence of C. concisus as an intestinal pathogen, but more significantly, provide novel insights into the host immune response and an explanation for the heterogeneity observed in the outcome of C. concisus infection. Moreover, response to infection with invasive strains has substantial similarities to that observed in the inflamed mucosa of Crohn's disease patients.
Also flagged:P38 MAPKNMDA receptorHuntington diseaseHDneurodegenerative diseaseN-methyl-d-aspartate
Journal Article2011-12-14✓ 4 SnippetsFan J, Gladding CM, Wang L, Zhang LY, Kaufman AM, Milnerwood AJ, Raymond LA.
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…Huntington disease (HD) is a dominantly inherited neurodegenerative disease caused by a polyglutamine (polyQ) expansion in the protein huntingtin (htt).…
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…the protein huntingtin (htt).…
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…(MSNs) from mutanthtt(mhtt)-enhanced NMDAR toxicity…
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…(YAC) mice expressinghttwith 128 polyQ…
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Huntington disease (HD) is a dominantly inherited neurodegenerative disease caused by a polyglutamine (polyQ) expansion in the protein huntingtin (htt). Previous studies have shown enhanced N-methyl-d-aspartate (NMDA)-induced excitotoxicity in neuronal models of HD, mediated in part by increased NMDA receptor (NMDAR) GluN2B subunit binding with the postsynaptic density protein-95 (PSD-95). In cultured hippocampal neurons, the NMDAR-activated p38 Mitogen-activated Protein Kinase (MAPK) death pathway is disrupted by a peptide (Tat-NR2B9c) that uncouples GluN2B from PSD-95, whereas NMDAR-mediated activation of c-Jun N-terminal Kinase (JNK) MAPK is PSD-95-independent. To investigate the mechanism by which Tat-NR2B9c protects striatal medium spiny neurons (MSNs) from mutant htt (mhtt)-enhanced NMDAR toxicity, we compared striatal tissue and cultured MSNs from presymptomatic yeast artificial chromosome (YAC) mice expressing htt with 128 polyQ (YAC128) to those from YAC18 and/or WT mice as controls. Similar to the previously published shift of GluN2B-containing NMDARs to extrasynaptic sites, we found increased PSD-95 localization as well as elevated PSD-95-GluN2B interactions in the striatal non-PSD (extrasynaptic) fraction from YAC128 mice. Notably, basal levels of both activated p38 and JNK MAPKs were elevated in the YAC128 striatum. NMDA stimulation of acute slices increased activation of p38 and JNK in WT and YAC128 striatum, but Tat-NR2B9c pretreatment reduced only the p38 activation in YAC128. In cultured MSNs, p38 MAPK inhibition reduced YAC128 NMDAR-mediated cell death to WT levels, and occluded the Tat-NR2B9c peptide protective effect; in contrast, inhibition of JNK had a similar protective effect in cultured MSNs from both WT and YAC128 mice. Our results suggest that altered activation of p38 MAPK contributes to mhtt enhancement of GluN2B/PSD-95 toxic signaling.
Also flagged:bindingpolyprenyl synthetaseXenazinepotassium channelK+serotonin receptor 2A
Journal Article2011-12-14No SnippetsPark K, Kim D.
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<h4>Background</h4>Drugs that bind to common targets likely exert similar activities. In this target-centric view, the inclusion of richer target information may better represent the relationships between drugs and their activities. Under this assumption, we expanded the "common binding rule" assumption of QSAR to create a new drug-drug relationship score (DRS).<h4>Method</h4>Our method uses various chemical features to encode drug target information into the drug-drug relationship information. Specifically, drug pairs were transformed into numerical vectors containing the basal drug properties and their differences. After that, machine learning techniques such as data cleaning, dimension reduction, and ensemble classifier were used to prioritize drug pairs bound to a common target. In other words, the estimation of the drug-drug relationship is restated as a large-scale classification problem, which provides the framework for using state-of-the-art machine learning techniques with thousands of chemical features for newly defining drug-drug relationships.<h4>Conclusions</h4>Various aspects of the presented score were examined to determine its reliability and usefulness: the abundance of common domains for the predicted drug pairs, c.a. 80% coverage for known targets, successful identifications of unknown targets, and a meaningful correlation with another cutting-edge method for analyzing drug similarities. The most significant strength of our method is that the DRS can be used to describe phenotypic similarities, such as pharmacological effects.
Also flagged:Osteoporosissystemic skeletal disordermineralcalciumphosphorusBone
Journal Article2011-12-14No SnippetsKourkoumelis N, Balatsoukas I, Tzaphlidou M.
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Osteoporosis is a systemic skeletal disorder associated with reduced bone mineral density and the consequent high risk of bone fractures. Current practice relates osteoporosis largely with absolute mass loss. The assessment of variations in chemical composition in terms of the main elements comprising the bone mineral and its effect on the bone's quality is usually neglected. In this study, we evaluate the ratio of the main elements of bone mineral, calcium (Ca), and phosphorus (P), as a suitable in vitro biomarker for induced osteoporosis. The Ca/P concentration ratio was measured at different sites of normal and osteoporotic rabbit bones using two spectroscopic techniques: Auger electron spectroscopy (AES) and energy-dispersive X-ray spectroscopy (EDX). Results showed that there is no significant difference between samples from different genders or among cortical bone sites. On the contrary, we found that the Ca/P ratio of trabecular bone sections is comparable to cortical sections with induced osteoporosis. Ca/P ratio values are positively related to induced bone loss; furthermore, a different degree of correlation between Ca and P in cortical and trabecular bone is evident. This study also discusses the applicability of AES and EDX to the semiquantitative measurements of bone mineral's main elements along with the critical experimental parameters.
Axon regeneration is a fundamental problem facing neuroscientists and clinicians. Failure of axon regeneration is caused by both extrinsic and intrinsic mechanisms. New techniques to examine gene expression such as Next Generation Sequencing of the Transcriptome (RNA-Seq) drastically increase our knowledge of both gene expression complexity (RNA isoforms) and gene expression regulation. By utilizing RNA-Seq, gene expression can now be defined at the level of isoforms, an essential step for understanding the mechanisms governing cell identity, growth and ultimately cellular responses to injury and disease.
Also flagged:obesitydyslipidemianonalcoholic fatty liver diseasecancerliver steatosislipid droplets
Journal Article2011-12-13No SnippetsTainaka T, Shimada Y, Kuroyanagi J, Zang L, Oka T, Nishimura Y, Nishimura N, Tanaka T.
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<h4>Background</h4>High dietary intake of vegetable products is beneficial against obesity and its related diseases such as dyslipidemia, nonalcoholic fatty liver disease, and cancer. We previously developed a diet-induced obesity model of zebrafish (DIO-zebrafish) that develops visceral adiposity, dyslipidemia, and liver steatosis. Zebrafish is a polyphagous animal; thus we hypothesized that DIO-zebrafish could be used for transcriptome analysis of anti-obesity effects of vegetables.<h4>Results</h4>Each vegetable exhibited different effects against obesity. We focused on "Campari" tomato, which suppressed increase of body weight, plasma TG, and lipid droplets in livers of DIO-zebrafish. Campari tomato decreased srebf1 mRNA by increase of foxo1 gene expression, which may depend on high contents of β-carotene in this strain.<h4>Conclusions</h4>Campari tomato ameliorates diet-induced obesity, especially dyslipidemia and liver steatosis via downregulation of gene expression related to lipogenesis. DIO-zebrafish can discriminate the anti-obesity effects of different strains of vegetables, and will become a powerful tool to assess outcomes and find novel mechanisms of anti-obesity effects of natural products.
Juvenile hormone (JH) is a sesquiterpenoid of vital importance for insect development, yet the molecular basis of JH signaling remains obscure, mainly because a bona fide JH receptor has not been identified. Mounting evidence points to the basic helix-loop-helix (bHLH)/Per-Arnt-Sim (PAS) domain protein Methoprene-tolerant (Met) as the best JH receptor candidate. However, details of how Met transduces the hormonal signal are missing. Here, we demonstrate that Met specifically binds JH III and its biologically active mimics, methoprene and pyriproxyfen, through its C-terminal PAS domain. Substitution of individual amino acids, predicted to form a ligand-binding pocket, with residues possessing bulkier side chains reduces JH III binding likely because of steric hindrance. Although a mutation that abolishes JH III binding does not affect a Met-Met complex that forms in the absence of methoprene, it prevents both the ligand-dependent dissociation of the Met-Met dimer and the ligand-dependent interaction of Met with its partner bHLH-PAS protein Taiman. These results show that Met can sense the JH signal through direct, specific binding, thus establishing a unique class of intracellular hormone receptors.
Also flagged:TNFinflammatory diseasetumor necrosis factorTNF receptorTNFSFTNFRSF
Journal Article2011-12-13No SnippetsCroft M, Duan W, Choi H, Eun SY, Madireddi S, Mehta A.
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The tumor necrosis factor (TNF) and TNF receptor superfamilies (TNFSF and TNFRSF) consist of approximately 50 membrane and soluble proteins that can modulate cellular function. Most of these molecules are expressed by or can target cells of the immune system, and they have a wide range of actions including promoting cellular differentiation, survival, and production of inflammatory cytokines and chemokines. Emerging data show that TNFSF ligand-receptor signaling pathways are active in inflammatory and autoimmune disease. Furthermore, several genetic polymorphisms in TNFSF and TNFRSF associate with susceptibility to developing disease. Here, we examine recent data regarding the potential of these molecules as targets for therapy of autoimmune and inflammatory disease.
Single large doses of methamphetamine (METH) cause endoplasmic reticulum (ER) stress and mitochondrial dysfunctions in rodent striata. The dopamine D(1) receptor appears to be involved in these METH-mediated stresses. The purpose of this study was to investigate if dopamine D(1) and D(2) receptors are involved in ER and mitochondrial stresses caused by single-day METH binges in the rat striatum. Male Sprague-Dawley rats received 4 injections of 10 mg/kg of METH alone or in combination with a putative D(1) or D(2) receptor antagonist, SCH23390 or raclopride, respectively, given 30 min prior to each METH injection. Rats were euthanized at various timepoints afterwards. Striatal tissues were used in quantitative RT-PCR and western blot analyses. We found that binge METH injections caused increased expression of the pro-survival genes, BiP/GRP-78 and P58(IPK), in a SCH23390-sensitive manner. METH also caused up-regulation of ER-stress genes, Atf2, Atf3, Atf4, CHOP/Gadd153 and Gadd34. The expression of heat shock proteins (HSPs) was increased after METH injections. SCH23390 completely blocked induction in all analyzed ER stress-related proteins that included ATF3, ATF4, CHOP/Gadd153, HSPs and caspase-12. The dopamine D(2)-like antagonist, raclopride, exerted small to moderate inhibitory influence on some METH-induced changes in ER stress proteins. Importantly, METH caused decreases in the mitochondrial anti-apoptotic protein, Bcl-2, but increases in the pro-apoptotic proteins, Bax, Bad and cytochrome c, in a SCH23390-sensitive fashion. In contrast, raclopride provided only small inhibition of METH-induced changes in mitochondrial proteins. These findings indicate that METH-induced activation of striatal ER and mitochondrial stress pathways might be more related to activation of SCH23390-sensitive receptors.
Also flagged:Endometriosisgene expressionpathogenesisovarian endometriosiscell proliferationsteroidogenesis
Journal Article2011-12-13No SnippetsAbu-Asab M, Zhang M, Amini D, Abu-Asab N, Amri H.
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Endometriosis is a multifactorial disease with poorly understood etiology, and reflecting an evolutionary nature where genetic alterations accumulate throughout pathogenesis. Our objective was to characterize the heterogeneous pathological process using parsimony phylogenetics. Gene expression microarray data of ovarian endometriosis obtained from NCBI database were polarized and coded into derived (abnormal) and ancestral (normal) states. Such alterations are referred to as synapomorphies in a phylogenetic sense (or biomarkers). Subsequent gene linkage was modeled by Genomatix BiblioSphere Pathway software. A list of clonally shared derived (abnormal) expressions revealed the pattern of heterogeneity among specimens. In addition, it has identified disruptions within the major regulatory pathways including those involved in cell proliferation, steroidogenesis, angiogenesis, cytoskeletal organization and integrity, and tumorigenesis, as well as cell adhesion and migration. Furthermore, the analysis supported the potential central involvement of ESR2 in the initiation of endometriosis. The pathogenesis mapping showed that eutopic and ectopic lesions have different molecular biosignatures.
Also flagged:oncoproteinBcr-AblautophosphorylationCMLbindingchronic myelogenous leukemia
Journal Article2011-12-12✓ 1 SnippetDixon AS, Miller GD, Bruno BJ, Constance JE, Woessner DW, Fidler TP, Robertson JC, Cheatham TE, Lim CS.
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The oncoprotein Bcr-Abl drives aberrant downstream activity through trans-autophosphorylation of homo-oligomers in chronic myelogenous leukemia (CML).(1, 2) The formation of Bcr-Abl oligomers is achieved through the coiled-coil domain at the N-terminus of Bcr.(3, 4) We have previously reported a modified version of this coiled-coil domain, CCmut2, which exhibits disruption of Bcr-Abl oligomeric complexes and results in decreased proliferation of CML cells and induction of apoptosis.(5) A major contributing factor to these enhanced capabilities is the destabilization of the CCmut2 homodimers, increasing the availability to interact with and inhibit Bcr-Abl. Here, we included an additional mutation (K39E) that could in turn further destabilize the mutant homodimer. Incorporation of this modification into CCmut2 (C38A, S41R, L45D, E48R, Q60E) generated what we termed CCmut3, and resulted in further improvements in the binding properties with the wild-type coiled-coil domain representative of Bcr-Abl [corrected]. A separate construct containing one revert mutation, CCmut4, did not demonstrate improved oligomeric properties and indicated the importance of the L45D mutation. CCmut3 demonstrated improved oligomerization via a two-hybrid assay as well as through colocalization studies, in addition to showing similar biologic activity as CCmut2. The improved binding between CCmut3 and the Bcr-Abl coiled-coil may be used to redirect Bcr-Abl to alternative subcellular locations with interesting therapeutic implications.
…Onset of Huntington's disease is attributed to the presence of a high number of CAG trinucleotide repeat lengths within the Huntingtin (HTT) gene [12,13]; in particular, when the number of CAG repeats exceeds 37, onset of Huntington's disease symptoms was much more likely to occur [14].…
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…Hemochromatosis, a well-known blood disease, has a very clear genetic basis in its manifestation and progression [59] and is often the result of many different potential mutations to different genes with the most common mutation being the C282Y mutation of the HFE gene.…
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…Evidence suggests that individuals heterozygous for the C282Y mutation in the HFE gene may experience benefit due to more efficient dietary iron absorption and via increased resistance to typhoid fever and tuberculosis, diseases that became more prevalent with the rise of urbanization [59].…
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…within the Huntingtin (HTT) gene [ 12…
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…length within theHTTgene therefore seems…
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<h4>Background</h4>Many serious diseases have a genetic basis which, from an evolutionary point of view, should have been selected against, resulting in very low frequencies. The remarkable sustained prevalence of a number of disease-associated alleles is therefore surprising. We believe that antagonistic pleiotropy, when multiple effects of a gene have opposing effects on fitness (e.g., sickle cell disease), may be more widespread than typically considered. We hypothesize that, rather than being an exception to the rule of genetic disorders, antagonistic pleiotropy may be common.<h4>Methods</h4>We surveyed the medical literature in order to determine whether sufficient evidence exists to reassess the nature of antagonistic pleiotropy; from being considered an unusual scenario to one that is anticipated. We also used a simple population genetic model to examine the feasibility of antagonistic pleiotropy to act as a mechanism to maintain polymorphism for serious genetic disorders even if the benefits are subtle.<h4>Results</h4>We identified a number of examples of antagonistic pleiotropy where the deleterious effect, the beneficial effect, and the exact molecular cause have been demonstrated. We also identified putative cases in which there is circumstantial evidence or a strong reason to expect antagonistic pleiotropy in a genetic disorder. The population genetic model demonstrates that alleles with severe deleterious health effects can be maintained at medically relevant frequencies with only minor beneficial pleiotropic effects.<h4>Conclusion</h4>We believe that our identification of several cases of antagonistic pleiotropy, despite the lack of research on this question and the varied natures of the types of these disorders, speaks to both the underappreciated nature of this phenomenon and its potentially fundamental importance. If antagonistic pleiotropy is as common as our research suggests, this may explain why so many serious diseases, even apparently environmentally caused ones, have a genetic component. Furthermore, acceptance of a genome full of antagonistically pleiotropic genetic interactions poses important implications for clinical treatment and disease prevention research, especially genetically based therapies.
Also flagged:irongene expressionmetabolismimmune responsespathogenesisnitrogen
Journal Article2011-12-12✓ 2 SnippetsBohne F, Martínez-Llordella M, Lozano JJ, Miquel R, Benítez C, Londoño MC, Manzia TM, Angelico R, Swinkels DW, Tjalsma H, López M, Abraldes JG, Bonaccorsi-Riani E, Jaeckel E, Taubert R, Pirenne J, Rimola A, Tisone G, Sánchez-Fueyo A.
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Following organ transplantation, lifelong immunosuppressive therapy is required to prevent the host immune system from destroying the allograft. This can cause severe side effects and increased recipient morbidity and mortality. Complete cessation of immunosuppressive drugs has been successfully accomplished in selected transplant recipients, providing proof of principle that operational allograft tolerance is attainable in clinical transplantation. The intra-graft molecular pathways associated with successful drug withdrawal, however, are not well defined. In this study, we analyzed sequential blood and liver tissue samples collected from liver transplant recipients enrolled in a prospective multicenter immunosuppressive drug withdrawal clinical trial. Before initiation of drug withdrawal, operationally tolerant and non-tolerant recipients differed in the intra-graft expression of genes involved in the regulation of iron homeostasis. Furthermore, as compared with non-tolerant recipients, operationally tolerant patients exhibited higher serum levels of hepcidin and ferritin and increased hepatocyte iron deposition. Finally, liver tissue gene expression measurements accurately predicted the outcome of immunosuppressive withdrawal in an independent set of patients. These results point to a critical role for iron metabolism in the regulation of intra-graft alloimmune responses in humans and provide a set of biomarkers to conduct drug-weaning trials in liver transplantation.
…To determine whether key genetic determinants of the adenoma-to-carcinoma sequence are differentially expressed by CD133+ versus CD133− colon cancer cells, we compared the gene expression levels of oncogenes (Src, Raf-1, Met, K-ras), tumor suppressor genes (APC,DCC, TP53, PTEN), DNA mismatch repair genes (MLH1, MSH2, MSH, MGMT) and other genes specific for colon carcinogenesis (CHK2, TGFBR2).…
Experimental data indicate that colorectal cancer cells with CD133 expression exhibit enhanced tumorigenicity over CD133-negative (CD133-) cells. We hypothesized that CD133-positive (CD133+) cells, compared with CD133-, are more tumorigenic because they are more interactive with and responsive to their stromal microenvironment. Freshly dissected and dissociated cells from a primary colon cancer were separated into carcinoma-associated fibroblasts (CAF) and the epithelial cells; the latter were further separated into CD133+ and CD133- cells using fluorescence-activated cell sorter. The CD133+ cells formed large tumors in non-obese diabetic-severe combined immunodeficient (NOD-SCID) mice, demonstrating the phenotypic cellular diversity of the original tumor, whereas CD133- cells were unable to sustain significant growth. Affymetrix gene array analyses using t-test, fold-change and multiple test correction identified candidate genes that were differentially expressed between the CD133+ vs CD133- cells. RT-PCR verified differences in expression for 30 of the 46 genes selected. Genes upregulated (+ vs - cells) included CD133 (9.3-fold) and CXCR4 (4-fold), integrin β8 and fibroblast growth factor receptor 2. The CAF highly express the respective ligands: stromal-derived factor-1 (SDF-1), vitronectin and FGF family members, suggesting a reciprocal relationship between the CD133+ and CAF cells. SDF-1 caused an increase in intracellular calcium in cells expressing both CD133 and CXCR4, confirming functional CXCR4. The CD133+/CXCR4+ phenotype is increased to 32% when the cells are grown in suspension compared with only 9% when the cells were allowed to attach. In Matrigel 3-D culture, the CD133+/CXCR4+ group treated with SDF-1 grew more colonies compared with vehicle, as well as significantly larger colony sizes of tumor spheres. These data demonstrate proof of principle that the enhanced tumorigenic potential of CD133+, compared with CD133-, cells is due to their increased ability to interact with their neighboring CAF.
Mini-chromosome maintenance (Mcm) proteins are part of the replication-licensing complex that is loaded onto chromatin during the G1-phase of the cell cycle and required for initiation of DNA replication in the subsequent S-phase. Mcm proteins are typically loaded in excess of the number of locations that are used during S-phase. Nonetheless, partial depletion of Mcm proteins leads to cancers and stem cell deficiencies. Mcm2 deficient mice, on a 129Sv genetic background, display a high rate of thymic lymphoblastic lymphoma. Here array comparative genomic hybridization is used to characterize the genetic damage accruing in these tumors. The predominant events are deletions averaging less than 0.5 Mbp, considerably shorter than observed in prior studies using alternative mouse lymphoma models or human tumors. Such deletions facilitate identification of specific genes and pathways responsible for the tumors. Mutations in many genes that have been implicated in human lymphomas are recapitulated in this mouse model. These features, and the fact that the mutation underlying the accelerated genetic damage does not target a specific gene or pathway a priori, are valuable features of this mouse model for identification of tumor suppressor genes. Genes affected in all tumors include Pten, Tcfe2a, Mbd3 and Setd1b. Notch1 and additional genes are affected in subsets of tumors. The high frequency of relatively short deletions is consistent with elevated recombination between nearby stalled replication forks in Mcm2-deficient mice.
Also flagged:Farnesolbiofilm formationsynthesisplagiochin Fisoriccardin CDpp3
Journal Article2011-12-12No SnippetsZhang L, Chang W, Sun B, Groh M, Speicher A, Lou H.
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The yeast-to-hypha transition plays a crucial role in the pathogenesis of C. albicans. Farnesol, a quorum sensing molecule (QSM) secreted by the fungal itself, could prevent the formation of hyphae and subsequently lead to the defect of biofilm formation. The DPP3, encoding phosphatase, is a key gene in regulating farnesol synthesis. In this study, we screened 24 bisbibenzyls and 2 bibenzyls that were isolated from bryophytes or chemically synthesized by using CLSI method for antifungal effect. Seven bisbibenzyls were found to have antifungal effects with IC(80) less than 32 µg/ml, and among them, plagiochin F, isoriccardin C and BS-34 were found to inhibit the hyphae and biofilm formation of C. albicans in a dose-dependent manner. To uncover the underlying relationship between morphogenesis switch and QSM formation, we measured the farnesol production by HPLC-MS and quantified Dpp3 expression by detecting the fluorescent intensity of green fluorescent protein tagged strain using Confocal Laser Scanning microscopy and Multifunction Microplate Reader. The DPP3 transcripts were determined by real-time PCR. The data indicated that the bisbibenzyls exerted antifungal effects through stimulating the synthesis of farnesol via upregulation of Dpp3, suggesting a potential antifungal application of bisbibenzyls. In addition, our assay provides a novel, visual and convenient method to measure active compounds against morphogenesis switch.
Also flagged:injurygene expressionnerve injurytranscription factorsaxonaltranscriptional factors
Journal Article2011-12-12✓ 1 SnippetKiryu-Seo S, Kiyama H.
In-Text Gene Mentions
S I O 001029)
…In HD pathology, mutant huntingtin (Htt) interacts with Sp1 and core components of the transcriptional machinery, leading to disruption of transcriptional activation of neuronal genes such as the dopamine D2 receptor (Dunah et al., 2002; Freiman and Tjian, 2002; Zhai et al., 2005 ).…
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Peripheral nervous system (PNS) neurons survive and regenerate after nerve injury, whereas central nervous system (CNS) neurons lack the capacity to do so. The inability of the CNS to regenerate presumably results from a lack of intrinsic growth activity and a permissive environment. To achieve CNS regeneration, we can learn from successful nerve regeneration in the PNS. Neurons in the PNS elicit dynamic changes in gene expression in response to permissive environmental cues following nerve injury. To switch gene expression on and off in injured neurons, transcription factors and their networks should be carefully orchestrated according to the regeneration program. This is the so-called "intrinsic power of axonal growth." There is an increasing repertoire of candidate transcription factors induced by nerve injury. Some of them potentiate the survival and axonal regeneration of damaged neurons in vivo; however, our knowledge of transcriptional events in injured neurons is still limited. How do these transcription factors communicate with each other? How does the transcriptional machinery regulate the wide variety of regeneration-associated genes (RAGs) in the properly coordinated manner? In this review, we describe our current understanding of the injury-inducible transcriptional factors that enhance the intrinsic growth capacity, and propose a potential role for specificity protein 1 (Sp1), which provides a platform to recruit injury-inducible transcription factors, in simultaneous gene regulation. Finally, we discuss an additional mechanism that is involved in epigenetic modifications in damaged neurons. A comprehensive understanding of the nuclear events in injured neurons will provide clues to clinical interventions for successful nerve regeneration.
Also flagged:tumourcolorectal carcinomagene expressioncolorectal cancersnetrin-1cancer
Journal Article2011-12-11✓ 5 SnippetsCastets M, Broutier L, Molin Y, Brevet M, Chazot G, Gadot N, Paquet A, Mazelin L, Jarrosson-Wuilleme L, Scoazec JY, Bernet A, Mehlen P.
In-Text Gene Mentions
Abstract)
…These results demonstrate that DCC functions as a tumour suppressor via its ability to trigger tumour cell apoptosis.…
Abstract)
…Loss of DCC-induced apoptosis is also associated with an increase in the number and aggressiveness of intestinal tumours in a predisposing APC mutant context, resulting in the development of highly invasive adenocarcinomas.…
Abstract)
…DCC gene expression is lost or markedly reduced in the majority of advanced colorectal cancers and, by functioning as a dependence receptor, DCC has been shown to induce apoptosis unless engaged by its ligand, netrin-1 (ref.2).…
Abstract)
…However, so far no animal model has supported the view that the DCC loss-of-function is causally implicated as predisposing to aggressive cancer development.…
Abstract)
…To investigate the role of DCC-induced apoptosis in the control of tumour progression, here we created a mouse model in which the pro-apoptotic activity of DCC is genetically silenced.…
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The role of deleted in colorectal carcinoma (DCC) as a tumour suppressor has been a matter of debate for the past 15 years. DCC gene expression is lost or markedly reduced in the majority of advanced colorectal cancers and, by functioning as a dependence receptor, DCC has been shown to induce apoptosis unless engaged by its ligand, netrin-1 (ref. 2). However, so far no animal model has supported the view that the DCC loss-of-function is causally implicated as predisposing to aggressive cancer development. To investigate the role of DCC-induced apoptosis in the control of tumour progression, here we created a mouse model in which the pro-apoptotic activity of DCC is genetically silenced. Although the loss of DCC-induced apoptosis in this mouse model is not associated with a major disorganization of the intestines, it leads to spontaneous intestinal neoplasia at a relatively low frequency. Loss of DCC-induced apoptosis is also associated with an increase in the number and aggressiveness of intestinal tumours in a predisposing APC mutant context, resulting in the development of highly invasive adenocarcinomas. These results demonstrate that DCC functions as a tumour suppressor via its ability to trigger tumour cell apoptosis.
Also flagged:Huntington's diseaseHDneurological diseasecognitive impairmentopsintransducin
Journal Article2011-12-11No SnippetsBatcha AH, Greferath U, Jobling AI, Vessey KA, Ward MM, Nithianantharajah J, Hannan AJ, Kalloniatis M, Fletcher EL.
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Huntington's disease (HD) is a progressive neurological disease characterised by motor dysfunction, cognitive impairment and personality changes. Previous work in HD patients and animal models of the disease has also highlighted retinal involvement. This study characterised the changes in retinal structure and function early within the progression of disease using the R6/1 mouse model of HD. The retinal phenotype was observed to occur at the same time in the disease process as other neurological deficits such as motor dysfunction (by 13 weeks of age). There was a specific functional deficit in cone response to the electroretinogram and using immunocytochemical techniques, this dysfunction was found to be likely due to a progressive and complete loss of cone opsin and transducin protein expression by 20 weeks of age. In addition, there was an increase in Müller cell gliosis and the presence of ectopic rod photoreceptor terminals. This retinal remodelling is also observed in downstream neurons, namely the rod and cone bipolar cells. While R6/1 mice exhibit significant retinal pathology simultaneously with other more classical HD alterations, this doesn't lead to extensive cell loss. These findings suggest that in HD, cone photoreceptors are initially targeted, possibly via dysregulation of protein expression or trafficking and that this process is subsequently accompanied by increased retinal stress and neuronal remodelling also involving the rod pathway. As retinal structure and connectivity are well characterised, the retina may provide a useful model tissue in which to characterise the mechanisms important in the development of neuronal pathology in HD.
Also flagged:Asthmaairway hyperresponsivenessASMAHRcell surfacemembrane
Journal Article2011-12-11✓ 1 SnippetOzier A, Allard B, Bara I, Girodet PO, Trian T, Marthan R, Berger P.
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Introduction)
…and OX40 ligand (TNFSF4) [ 119 ,…
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Asthma is characterized by the association of airway hyperresponsiveness (AHR), inflammation, and remodelling. The aim of the present article is to review the pivotal role of airway smooth muscle (ASM) in the pathophysiology of asthma. ASM is the main effector of AHR. The mechanisms of AHR in asthma may involve a larger release of contractile mediators and/or a lower release of relaxant mediators, an improved ASM cell excitation/contraction coupling, and/or an alteration in the contraction/load coupling. Beyond its contractile function, ASM is also involved in bronchial inflammation and remodelling. Whereas ASM is a target of the inflammatory process, it can also display proinflammatory and immunomodulatory functions, through its synthetic properties and the expression of a wide range of cell surface molecules. ASM remodelling represents a key feature of asthmatic bronchial remodelling. ASM also plays a role in promoting complementary airway structural alterations, in particular by its synthetic function.
Plasma proteome is widely used in studying changes occurring in human body during disease or other disturbances. Immunological methods are commonly used in such studies. In recent years, mass spectrometry has gained popularity in high-throughput analysis of plasma proteins. In this study, we tested whether mass spectrometry and iTRAQ-based protein quantification might be used in proteomic analysis of human plasma during liver transplantation surgery to characterize changes in protein abundances occurring during early graft reperfusion. We sampled blood from systemic circulation as well as blood entering and exiting the liver. After immunodepletion of six high-abundant plasma proteins, trypsin digestion, iTRAQ labeling, and cation-exchange fractionation, the peptides were analyzed by reverse phase nano-LC-MS/MS. In total, 72 proteins were identified of which 31 could be quantified in all patient specimens collected. Of these 31 proteins, ten, mostly medium-to-high abundance plasma proteins with a concentration range of 50-2000 mg/L, displayed relative abundance change of more than 10%. The changes in protein abundance observed in this study allow further research on the role of several proteins in ischemia-reperfusion injury during liver transplantation and possibly in other surgery.
Also flagged:hyperglycemiaintracerebral hemorrhagecollagenaseheparinalbuminsugar
Journal Article2011-12-09No SnippetsChiu CD, Chen TY, Chin LT, Shen CC, Huo J, Ma SY, Chen HM, Chu CH.
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Intracerebral hemorrhage (ICH) is associated with high mortality and disability, and hyperglycemia worsens the clinical and neurological outcomes of patients with ICH. In this study, we utilized proteomic approaches to investigate the role of hyperglycemia in ICH. Hyperglycemia was induced by intraperitoneal injection of streptozotocin (STZ) in adult Sprague-Dawley male rats; ICH was induced by stereotaxic infusion of collagenase/heparin into the right striatum. It was observed that the size of induced hemorrhage was significantly larger in the hyperglycemic group (n=6 in each group). On the first day after ICH, an apparent decrease in the bilateral grasp was also observed for the lesioned hyperglycemic rats compared with normoglycemic ones. When employing 2-DE and MS to examine the proteomes of perihematomal and control regions in individual hyperglycemic and normoglycemic rats, eight differentially expressed protein targets were identified. Most noteworthy, in response to ICH significant increase of albumin was ubiquitously observed in the brains of normoglycemic rats but not in the brains of hyperglycemic rats. Coincidentally, more significant neuronal apoptosis were found in the perihematomal regions of hyperglycemic rats. These observations described suggest the protection role of albumin in acute stage of ICH, which may be dependent on different blood sugar levels.
The reduction of hepatic microsomal transfer protein (MTP) activity results in fatty liver, worsening hepatic steatosis and fibrosis in chronic hepatitis C (CHC). The G allele of the MTP gene promoter, -493G/T, has been associated with lower transcriptional activity than the T allele. We investigated this association with metabolic and histological variables in patients with CHC. A total of 174 untreated patients with CHC were genotyped for MTP -493G/T by direct sequencing using PCR. All patients were negative for markers of Wilson's disease, hemochromatosis and autoimmune diseases and had current and past daily alcohol intake lower than 100 g/week. The sample distribution was in Hardy-Weinberg equilibrium. Among subjects with genotype 1, 56.8% of the patients with fibrosis grade 3+4 presented at least one G allele versus 34.3% of the patients with fibrosis grade 1+2 (OR = 1.8; 95%CI = 1.3-2.3). Logistic regression analysis with steatosis as the dependent variable identified genotypes GG+GT as independent protective factors against steatosis (OR = 0.4, 95%CI = 0.2-0.8; P = 0.01). The results suggest that the presence of the G allele of MTP -493G/T associated with lower hepatic MTP expression protects against steatosis in our CHC patients.
Fe deficiency and Fe-deficiency anaemia are common in patients with inflammatory bowel disease (IBD). Traditional clinical markers of Fe status can be skewed in the presence of inflammation, meaning that a patient's Fe status can be misinterpreted. Additionally, Fe absorption is known to be down-regulated in patients with active IBD. However, whether this is the case for quiescent or mildly active disease has not been formally assessed. The present study aimed to investigate the relationship between Fe absorption, Fe requirements and standard haematological indices in IBD patients without active disease. A group of twenty-nine patients with quiescent or mildly active IBD and twenty-eight control subjects undertook an Fe absorption test that measured sequential rises in serum Fe over 4 h following ingestion of 200 mg ferrous sulphate. At baseline, serum Fe, transferrin saturation, non-transferrin-bound Fe (NTBI), ferritin and soluble transferrin receptor were all measured. Thereafter (30-240 min), only serum Fe and NTBI were measured. Fe absorption did not differ between the two groups (P = 0·9; repeated-measures ANOVA). In control subjects, baseline haematological parameters predicted Fe absorption (i.e. Fe requirements), but this was not the case for patients with IBD. Fe absorption is normal in quiescent or mildly active IBD patients but standard haematological parameters do not accurately predict Fe requirements.
Also flagged:maltoseglucosefructoseamino acidsfermentationwater
Journal Article2011-12-09No SnippetsMinervini F, Di Cagno R, Lattanzi A, De Angelis M, Antonielli L, Cardinali G, Cappelle S, Gobbetti M.
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The study of the microbiotas of 19 Italian sourdoughs used for the manufacture of traditional/typical breads allowed the identification, through a culture-dependent approach, of 20 and 4 species of lactic acid bacteria (LAB) and yeasts, respectively. Numerically, the most frequent LAB isolates were Lactobacillus sanfranciscensis (ca. 28% of the total LAB isolates), Lactobacillus plantarum (ca. 16%), and Lactobacillus paralimentarius (ca. 14%). Saccharomyces cerevisiae was identified in 16 sourdoughs. Candida humilis, Kazachstania barnettii, and Kazachstania exigua were also identified. As shown by principal component analysis (PCA), a correlation was found between the ingredients, especially the type of flour, the microbial community, and the biochemical features of sourdoughs. Triticum durum flours were characterized by the high level of maltose, glucose, fructose, and free amino acids (FAA) correlated with the sole or main presence of obligately heterofermentative LAB, the lowest number of facultatively heterofermentative strains, and the low cell density of yeasts in the mature sourdoughs. This study highlighted, through a comprehensive and comparative approach, the dominant microbiotas of 19 Italian sourdoughs, which determined some of the peculiarities of the resulting traditional/typical Italian breads.
…The best hope for halting HD progression is to reduce or eliminate the mutant Htt protein in the affected cells [64, 65].…
S I O 001029)
…The pathology of HD is caused by a variable sized polyglutamine expansion of the protein product of the huntingtin (HTT) gene.…
Introduction)
…of the huntingtin (HTT) gene.…
Introduction)
…eliminate the mutantHttprotein in the…
Introduction)
…effective at reducingHttlevels and ameliorating…
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There is much interest in the use of mesenchymal stem cells/marrow stromal cells (MSC) to treat neurodegenerative disorders, in particular those that are fatal and difficult to treat, such as Huntington's disease. MSC present a promising tool for cell therapy and are currently being tested in FDA-approved phase I-III clinical trials for many disorders. In preclinical studies of neurodegenerative disorders, MSC have demonstrated efficacy, when used as delivery vehicles for neural growth factors. A number of investigators have examined the potential benefits of innate MSC-secreted trophic support and augmented growth factors to support injured neurons. These include overexpression of brain-derived neurotrophic factor and glial-derived neurotrophic factor, using genetically engineered MSC as a vehicle to deliver the cytokines directly into the microenvironment. Proposed regenerative approaches to neurological diseases using MSC include cell therapies in which cells are delivered via intracerebral or intrathecal injection. Upon transplantation, MSC in the brain promote endogenous neuronal growth, encourage synaptic connection from damaged neurons, decrease apoptosis, reduce levels of free radicals, and regulate inflammation. These abilities are primarily modulated through paracrine actions. Clinical trials for MSC injection into the central nervous system to treat amyotrophic lateral sclerosis, traumatic brain injury, and stroke are currently ongoing. The current data in support of applying MSC-based cellular therapies to the treatment of Huntington's disease is discussed.
Direct cellular reprogramming is a powerful new tool for regenerative medicine. In efforts to understand and treat Parkinson's Disease (PD), which is marked by the degeneration of dopaminergic neurons in the midbrain, direct reprogramming provides a valuable new source of these cells. Astrocytes, the most plentiful cells in the central nervous system, are an ideal starting population for the direct generation of dopaminergic neurons. In addition to their potential utility in cell replacement therapies for PD or in modeling the disease in vitro, astrocyte-derived dopaminergic neurons offer the prospect of direct in vivo reprogramming within the brain. As a first step toward this goal, we report the reprogramming of astrocytes to dopaminergic neurons using three transcription factors - ASCL1, LMX1B, and NURR1 - delivered in a single polycistronic lentiviral vector. The process is efficient, with 18.2±1.5% of cells expressing markers of dopaminergic neurons after two weeks. The neurons exhibit expression profiles and electrophysiological characteristics consistent with midbrain dopaminergic neurons, notably including spontaneous pacemaking activity, stimulated release of dopamine, and calcium oscillations. The present study is the first demonstration that a single vector can mediate reprogramming to dopaminergic neurons, and indicates that astrocytes are an ideal starting population for the direct generation of dopaminergic neurons.
<h4>Background</h4>Retinal detachment often leads to a severe and permanent loss of vision and its therapeutic management remains to this day exclusively surgical. We have used surgical specimens to perform a differential analysis of the transcriptome of human retinal tissues following detachment in order to identify new potential pharmacological targets that could be used in combination with surgery to further improve final outcome.<h4>Methodology/principal findings</h4>Statistical analysis reveals major involvement of the immune response in the disease. Interestingly, using a novel approach relying on coordinated expression, the interindividual variation was monitored to unravel a second crucial aspect of the pathological process: the death of photoreceptor cells. Within the genes identified, the expression of the major histocompatibility complex I gene HLA-C enables diagnosis of the disease, while PKD2L1 and SLCO4A1 -which are both down-regulated- act synergistically to provide an estimate of the duration of the retinal detachment process. Our analysis thus reveals the two complementary cellular and molecular aspects linked to retinal detachment: an immune response and the degeneration of photoreceptor cells. We also reveal that the human specimens have a higher clinical value as compared to artificial models that point to IL6 and oxidative stress, not implicated in the surgical specimens studied here.<h4>Conclusions/significance</h4>This systematic analysis confirmed the occurrence of both neurodegeneration and inflammation during retinal detachment, and further identifies precisely the modification of expression of the different genes implicated in these two phenomena. Our data henceforth give a new insight into the disease process and provide a rationale for therapeutic strategies aimed at limiting inflammation and photoreceptor damage associated with retinal detachment and, in turn, improving visual prognosis after retinal surgery.
Also flagged:polyglutamineHuntington's diseasepeptidepeptidesglutamine
Journal Article2011-12-09✓ 5 SnippetsJayaraman M, Kodali R, Sahoo B, Thakur AK, Mayasundari A, Mishra R, Peterson CB, Wetzel R.
In-Text Gene Mentions
Abstract)
…However, only htt(NT)Q(N) peptides with N=8 or more undergo conversion into polyQ β-sheet aggregates.…
Abstract)
…disease protein huntingtin (htt) dramatically increases aggre…
Abstract)
…37, aggregation ofhttN-terminal fragments is…
Abstract)
…repeat lengths inhttN-terminal fragments to…
Abstract)
…mino-acid N-terminal segment (httNT ) that…
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The 17-amino-acid N-terminal segment (htt(NT)) that leads into the polyglutamine (polyQ) segment in the Huntington's disease protein huntingtin (htt) dramatically increases aggregation rates and changes the aggregation mechanism, compared to a simple polyQ peptide of similar length. With polyQ segments near or above the pathological repeat length threshold of about 37, aggregation of htt N-terminal fragments is so rapid that it is difficult to tease out mechanistic details. We describe here the use of very short polyQ repeat lengths in htt N-terminal fragments to slow this disease-associated aggregation. Although all of these peptides, in addition to htt(NT) itself, form α-helix-rich oligomeric intermediates, only peptides with Q(N) of eight or longer mature into amyloid-like aggregates, doing so by a slow increase in β-structure. Concentration-dependent circular dichroism and analytical ultracentrifugation suggest that the htt(NT) sequence, with or without added glutamine residues, exists in solution as an equilibrium between disordered monomer and α-helical tetramer. Higher order, α-helix rich oligomers appear to be built up via these tetramers. However, only htt(NT)Q(N) peptides with N=8 or more undergo conversion into polyQ β-sheet aggregates. These final amyloid-like aggregates not only feature the expected high β-sheet content but also retain an element of solvent-exposed α-helix. The α-helix-rich oligomeric intermediates appear to be both on- and off-pathway, with some oligomers serving as the pool from within which nuclei emerge, while those that fail to undergo amyloid nucleation serve as a reservoir for release of monomers to support fibril elongation. Based on a regular pattern of multimers observed in analytical ultracentrifugation, and a concentration dependence of α-helix formation in CD spectroscopy, it is likely that these oligomers assemble via a four-helix assembly unit. PolyQ expansion in these peptides appears to enhance the rates of both oligomer formation and nucleation from within the oligomer population, by structural mechanisms that remain unclear.
Also flagged:prolineD-amino acidpeptidesproteased-amino acidsamino acid
Journal Article2011-12-09✓ 5 SnippetsMishra R, Jayaraman M, Roland BP, Landrum E, Fullam T, Kodali R, Thakur AK, Arduini I, Wetzel R.
In-Text Gene Mentions
Abstract)
…Here we demonstrate the kinetic importance of htt(NT) self-assembly by describing inhibitory htt(NT)-containing peptides that appear to work by targeting nucleation within the oligomer fraction.…
Abstract)
…huntingtin (htt) in the oligomer-mediated amyloid…
Abstract)
…amyloid assembly ofhttN-terminal fragments.…
Abstract)
…domains of polyQ-containinghttN-terminal fragments.…
Abstract)
…acid N-terminal segment (httNT ) of…
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Although oligomeric intermediates are transiently formed in almost all known amyloid assembly reactions, their mechanistic roles are poorly understood. Recently, we demonstrated a critical role for the 17-amino-acid N-terminus (htt(NT) segment) of huntingtin (htt) in the oligomer-mediated amyloid assembly of htt N-terminal fragments. In this mechanism, the htt(NT) segment forms the α-helix-rich core of the oligomers, leaving much of the polyglutamine (polyQ) segment disordered and solvent-exposed. Nucleation of amyloid structure occurs within this local high concentration of disordered polyQ. Here we demonstrate the kinetic importance of htt(NT) self-assembly by describing inhibitory htt(NT)-containing peptides that appear to work by targeting nucleation within the oligomer fraction. These molecules inhibit amyloid nucleation by forming mixed oligomers with the htt(NT) domains of polyQ-containing htt N-terminal fragments. In one class of inhibitors, nucleation is passively suppressed due to the reduced local concentration of polyQ within the mixed oligomer. In the other class, nucleation is actively suppressed by a proline-rich polyQ segment covalently attached to htt(NT). Studies with D-amino acid and scrambled sequence versions of htt(NT) suggest that inhibition activity is strongly linked to the propensity of inhibitory peptides to make amphipathic α-helices. Htt(NT) derivatives with C-terminal cell-penetrating peptide segments also exhibit excellent inhibitory activity. The htt(NT)-based peptides described here, especially those with protease-resistant d-amino acids and/or with cell-penetrating sequences, may prove useful as lead therapeutics for inhibiting the nucleation of amyloid formation in Huntington's disease.
Also flagged:polyunsaturated fatty acidsarachidonic aciddocosahexaenoic acidmembranephospholipidmetabolism
Journal Article2011-12-09✓ 2 SnippetsBasselin M, Ramadan E, Rapoport SI.
In-Text Gene Mentions
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…5-HTT…
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…5-HTT reuptake transporter…
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The polyunsaturated fatty acids (PUFAs), arachidonic acid (AA, 20:4n-6) and docosahexaenoic acid (DHA, 22:6n-3), important second messengers in brain, are released from membrane phospholipid following receptor-mediated activation of specific phospholipase A(2) (PLA(2)) enzymes. We developed an in vivo method in rodents using quantitative autoradiography to image PUFA incorporation into brain from plasma, and showed that their incorporation rates equal their rates of metabolic consumption by brain. Thus, quantitative imaging of unesterified plasma AA or DHA incorporation into brain can be used as a biomarker of brain PUFA metabolism and neurotransmission. We have employed our method to image and quantify effects of mood stabilizers on brain AA/DHA incorporation during neurotransmission by muscarinic M(1,3,5), serotonergic 5-HT(2A/2C), dopaminergic D(2)-like (D(2), D(3), D(4)) or glutamatergic N-methyl-d-aspartic acid (NMDA) receptors, and effects of inhibition of acetylcholinesterase, of selective serotonin and dopamine reuptake transporter inhibitors, of neuroinflammation (HIV-1 and lipopolysaccharide) and excitotoxicity, and in genetically modified rodents. The method has been extended for the use with positron emission tomography (PET), and can be employed to determine how human brain AA/DHA signaling and consumption are influenced by diet, aging, disease and genetics.
We report the fourth case of transthyretin amyloidosis (ATTR) Ser23Asn in a 41-year-old Ecuadorian male. He has a pedigree that spans seven generations and involves 24 family members who suffered early cardiac death. Salient presenting symptoms were fatigue, shortness of breath, and peripheral neuropathy. The diagnosis of cardiac amyloid was confirmed by immunohistochemical staining of an endomyocardial biopsy, genotyping and by technetium pyrophosphate ((99m)Tc-PYP) scintigraphy, which remains to be established as a reliable tool to visualize myocardial amyloid involvement in patients with the Ser23Asn transthyretin (TTR) variant. The patient underwent successful combined heart and liver transplant. We add to the current ATTR literature that in patients with the rare Ser23Asn mutation, peripheral nerve in addition to cardiac involvement can occur and (99m)Tc-PYP scintigraphy can be used as an imaging modality to visualize myocardial amyloid.
A 46-year-old woman with a vitelliform macular lesion secondary to desferrioxamine retinal toxicity in the right eye was treated with brinzolamide 1% ophthalmic drops three times a day. A spectral-domain optical coherence tomography (SD-OCT) unit was used to monitor any changes in the macular lesion. Two months after starting the eye drops, the SD-OCT showed a notable improvement in the vitelliform macular lesion's thickness. Six months later, further improvement was noted in the macular lesion thickness on SD-OCT testing in the right eye. Best-corrected visual acuity was initially 1.00 logarithm of the minimum angle of resolution (20/200 on a Snellen acuity chart) in the right eye and 0.14 logarithm of the minimum angle of resolution (20/25(-2)) in the left eye. After 6 months of treatment, visual acuity was 0.92 (20/200(+1)) in the right eye and 0.08 (20/25(+1)) in the left eye. The use of brinzolamide 1% was associated with a marked reduction in a vitelliform macular lesion on SD-OCT testing secondary to desferrioxamine retinal toxicity.
Also flagged:systemic lupus erythematosusSLEautoimmune diseasesautoimmune disordersMHCVTCN1
Journal Article2011-12-08✓ 5 SnippetsRamos PS, Criswell LA, Moser KL, Comeau ME, Williams AH, Pajewski NM, Chung SA, Graham RR, Zidovetzki R, Kelly JA, Kaufman KM, Jacob CO, Vyse TJ, Tsao BP, Kimberly RP, Gaffney PM, Alarcón-Riquelme ME, Harley JB, Langefeld CD, International Consortium on the Genetics of Systemic Erythematosus.
In-Text Gene Mentions
Discussion)
…Also, several established SLE loci are apparently not associated with other ADs, including the ITGAM-ITGAX region, TNFSF4, PTTG1, PHRF1, WDFY4 and BANK1 regions.…
Abstract)
…For many of the shared GWAS autoimmune loci, we found no evidence for association with SLE, including IL23R. Also, several established SLE loci are apparently not associated with other ADs, including the ITGAM-ITGAX and TNFSF4 regions.…
In spite of the well-known clustering of multiple autoimmune disorders in families, analyses of specific shared genes and polymorphisms between systemic lupus erythematosus (SLE) and other autoimmune diseases (ADs) have been limited. Therefore, we comprehensively tested autoimmune variants for association with SLE, aiming to identify pleiotropic genetic associations between these diseases. We compiled a list of 446 non-Major Histocompatibility Complex (MHC) variants identified in genome-wide association studies (GWAS) of populations of European ancestry across 17 ADs. We then tested these variants in our combined Caucasian SLE cohorts of 1,500 cases and 5,706 controls. We tested a subset of these polymorphisms in an independent Caucasian replication cohort of 2,085 SLE cases and 2,854 controls, allowing the computation of a meta-analysis between all cohorts. We have uncovered novel shared SLE loci that passed multiple comparisons adjustment, including the VTCN1 (rs12046117, P = 2.02×10(-06)) region. We observed that the loci shared among the most ADs include IL23R, OLIG3/TNFAIP3, and IL2RA. Given the lack of a universal autoimmune risk locus outside of the MHC and variable specificities for different diseases, our data suggests partial pleiotropy among ADs. Hierarchical clustering of ADs suggested that the most genetically related ADs appear to be type 1 diabetes with rheumatoid arthritis and Crohn's disease with ulcerative colitis. These findings support a relatively distinct genetic susceptibility for SLE. For many of the shared GWAS autoimmune loci, we found no evidence for association with SLE, including IL23R. Also, several established SLE loci are apparently not associated with other ADs, including the ITGAM-ITGAX and TNFSF4 regions. This study represents the most comprehensive evaluation of shared autoimmune loci to date, supports a relatively distinct non-MHC genetic susceptibility for SLE, provides further evidence for previously and newly identified shared genes in SLE, and highlights the value of studies of potentially pleiotropic genes in autoimmune diseases.
Also flagged:Satb2transcription factoraxonsTAG1NPYamino acids
Journal Article2011-12-08✓ 2 SnippetsTashiro K, Teissier A, Kobayashi N, Nakanishi A, Sasaki T, Yan K, Tarabykin V, Vigier L, Sumiyama K, Hirakawa M, Nishihara H, Pierani A, Okada N.
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Discussion)
…Oct-1, FoxD3, HLF,POU3F2, E4BP4, FoxJ2, CREBP1,…
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…For example, Brn-2 (POU3F2or Oct-7), a…
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Short interspersed repetitive elements (SINEs) are highly repeated sequences that account for a significant proportion of many eukaryotic genomes and are usually considered "junk DNA". However, we previously discovered that many AmnSINE1 loci are evolutionarily conserved across mammalian genomes, suggesting that they may have acquired significant functions involved in controlling mammalian-specific traits. Notably, we identified the AS021 SINE locus, located 390 kbp upstream of Satb2. Using transgenic mice, we showed that this SINE displays specific enhancer activity in the developing cerebral cortex. The transcription factor Satb2 is expressed by cortical neurons extending axons through the corpus callosum and is a determinant of callosal versus subcortical projection. Mouse mutants reveal a crucial function for Sabt2 in corpus callosum formation. In this study, we compared the enhancer activity of the AS021 locus with Satb2 expression during telencephalic development in the mouse. First, we showed that the AS021 enhancer is specifically activated in early-born Satb2(+) neurons. Second, we demonstrated that the activity of the AS021 enhancer recapitulates the expression of Satb2 at later embryonic and postnatal stages in deep-layer but not superficial-layer neurons, suggesting the possibility that the expression of Satb2 in these two subpopulations of cortical neurons is under genetically distinct transcriptional control. Third, we showed that the AS021 enhancer is activated in neurons projecting through the corpus callosum, as described for Satb2(+) neurons. Notably, AS021 drives specific expression in axons crossing through the ventral (TAG1(-)/NPY(+)) portion of the corpus callosum, confirming that it is active in a subpopulation of callosal neurons. These data suggest that exaptation of the AS021 SINE locus might be involved in enhancement of Satb2 expression, leading to the establishment of interhemispheric communication via the corpus callosum, a eutherian-specific brain structure.
…majority of Huntingtin (Htt) S-acylation activity in…
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…the efficiency ofHttS-acylation by over…
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…proteins, such asHtt, is minimal or…
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…capable of S-acylatingHtteven in the…
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…direct binding ofHttby the ankyrin…
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Signal transduction from G-protein coupled receptors to MAPK cascades through heterotrimeric G-proteins has been described for many eukaryotic systems. One of the best-characterised examples is the yeast pheromone response pathway, which is negatively regulated by AKR1. AKR1-like proteins are present in all eukaryotes and contain a DHHC domain and six ankyrin repeats. Whilst the DHHC domain dependant S-acyl transferase (palmitoyl transferase) function of AKR1 is well documented it is not known whether the ankyrin repeats are also required for this activity. Here we show that the ankyrin repeats of AKR1 are required for full suppression of the yeast pheromone response pathway, by sequestration of the Gβγ dimer, and act independently of AKR1 S-acylation function. Importantly, the functions provided by the AKR1 ankyrin repeats and DHHC domain are not required on the same molecule to fully restore WT phenotypes and function. We also show that AKR1 molecules are S-acylated at locations other than the DHHC cysteine, increasing the abundance of AKR1 in the cell. Our results have important consequences for studies of AKR1 function, including recent attempts to characterise S-acylation enzymology and kinetics. Proteins similar to AKR1 are found in all eukaryotes and our results have broad implications for future work on these proteins and the control of switching between Gβγ regulated pathways.
…Prdx6 supports retention of the active oxidase complex in stimulated plasma membrane, and results with mutant proteins imply that Prdx6 serves an additional biochemical or structural role in supporting optimal NADPH oxidase activity.…
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…neutrophils, peroxiredoxin 6 (Prdx6), which has both…
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…The function ofPrdx6in phox activity…
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…siRNA-mediated suppression ofPrdx6resulted in decreased…
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…stimulated with PMA,Prdx6translocated to plasma…
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Neutrophils provide the first line of defense against microbial invasion in part through production of reactive oxygen species (ROS) which is mediated through activation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase generating superoxide anion (O2-). The phagocyte oxidase (phox) has multiple protein components that assemble on the plasma membrane in stimulated neutrophils. We recently described a protein in neutrophils, peroxiredoxin 6 (Prdx6), which has both peroxidase and phospholipase A2 (PLA2) activities and enhances oxidase activity in an SDS-activated, cell-free system. The function of Prdx6 in phox activity is further investigated. In reconstituted phox-competent K562 cells, siRNA-mediated suppression of Prdx6 resulted in decreased NADPH oxidase activity in response to formyl-methionyl-leucyl-phenylalanine (fMLP) or phorbol myristate acetate (PMA). In neutrophils stimulated with PMA, Prdx6 translocated to plasma membrane as demonstrated by Western blot and confocal microscopy. Translocation of Prdx6 in phox competent K562 cells required both p67phox and p47phox. In addition, plasma membrane from PMA-stimulated, oxidase competent K562 cells with siRNA-mediated Prdx6 suppression contained less p47phox and p67phox compared to cells in which Prdx6 was not decreased. Cell-free oxidase assays showed that recombinant Prdx6 did not alter the Km for NADPH, but increased the Vmax for O2- production in a saturable, Prdx6 concentration-dependent manner. Recombinant proteins with mutations in Prdx (C47S) and phospholipase (S32A) activity both enhanced cell-free phox activity to the same extent as wild type protein. Prdx6 supports retention of the active oxidase complex in stimulated plasma membrane, and results with mutant proteins imply that Prdx6 serves an additional biochemical or structural role in supporting optimal NADPH oxidase activity.
Also flagged:iron transporterironexporterFPN1SLC40A1manganese
Journal Article2011-12-08✓ 1 SnippetMadejczyk MS, Ballatori N.
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…hemochromatosis…
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The present study examined the hypothesis that the iron exporter ferroportin (FPN1/SLC40A1) can also mediate cellular export of the essential trace element manganese, using Xenopus laevis oocytes expressing human FPN1. When compared to oocytes expressing only the divalent metal transporter-1 (DMT1/NRAMP2), (54)Mn accumulation was lower in oocytes also expressing FPN1. FPN1-expressing oocytes exported more (54)Mn than control oocytes (26.6±0.6% versus 7.1±0.5%, respectively, over 4h at pH 7.4 when preloaded with approximately 16μM (54)Mn); however, there was no difference in (54)Mn uptake between control and FPN1-expressing oocytes. FPN1-mediated Mn export was concentration dependent and could be partially cis-inhibited by 100μM Fe, Co, and Ni, but not by Rb. In addition, Mn export ability was significantly reduced when the extracellular pH was reduced from 7.4 to 5.5, and when Na(+) was substituted with K(+) in the incubation media. These results indicate that Mn is a substrate for FPN1, and that this export process is inhibited by a low extracellular pH and by incubation in a high K(+) medium, indicating the involvement of transmembrane ion gradients in FPN1-mediated transport.
Also flagged:hemoglobin Ssickle cell diseaseHb SironlipidHb
Journal Article2011-12-08✓ 4 SnippetsViana-Baracioli LM, Tukamoto Junior NC, Ricci Junior O, Mattos LC, Ângulo IL, Bonini-Domingos CR.
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Abstract)
…We evaluated the frequency of polymorphisms in the HFE gene in Hb AS blood donors and how these polymorphisms influenced lipid peroxidation and antioxidant capacity.…
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…Serum malondialdehyde values, indicative of lipid peroxidation, were highest in sickle cell patients, independent of the polymorphisms in the HFE gene, with significant differences, showing the influence of Hb S allele in the levels of lipid peroxidation.…
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…polymorphisms in theHFEgene in Hb…
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…polymorphisms in theHFEgene, with significant…
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It is well documented that Hb S and iron affect blood cells, and trigger oxidative processes and generation of free radicals with potential for lipid peroxidation. We evaluated the frequency of polymorphisms in the HFE gene in Hb AS blood donors and how these polymorphisms influenced lipid peroxidation and antioxidant capacity. Blood samples were collected from 211 Hb AS blood donors, 119 Hb AA blood donors as a control group, and 28 sickle cell disease patients (Hb SS). The H63D allele was found at a frequency of 10.5% in the Hb AS samples, and the C282Y allele frequency was 0.7%. In the control group, the frequencies of the H63D and C282Y alleles were 13.4 and 2.1%, respectively. In the sickle-cell disease patients, the H63D and the C282Y allele frequencies were 10.7 and 3.5%, respectively. The frequencies of the C282Y and H63D polymorphisms in Hb AS blood donors are similar to those reported for the Brazilian population. Serum malondialdehyde values, indicative of lipid peroxidation, were highest in sickle cell patients, independent of the polymorphisms in the HFE gene, with significant differences, showing the influence of Hb S allele in the levels of lipid peroxidation. However, the trolox equivalent antioxidant capacity average levels, indicative of the antioxidant capacity, were reduced with significant differences, indicating that in spite of a lipid peroxidation raise, this is not followed by the increased of the antioxidant capacity, leading to oxidative stress.
…Examination of mesenchymal stem cell-mediated RNAi transfer to Huntington's disease affected neuronal cells for reduction of huntingtin.…
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…expressing shRNA antisense to HTT were able to…
Abstract)
…Huntington's disease (HD) is a fatal, autosomal dominant neurodegenerative disorder caused by an expanded trinucleotide (CAG) repeat in exon 1 of the huntingtin gene (Htt).…
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…the huntingtin gene (Htt).…
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…the huntingtin protein (HTT).…
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Huntington's disease (HD) is a fatal, autosomal dominant neurodegenerative disorder caused by an expanded trinucleotide (CAG) repeat in exon 1 of the huntingtin gene (Htt). This expansion creates a toxic polyglutamine tract in the huntingtin protein (HTT). Currently, there is no treatment for either the progression or prevention of the disease. RNA interference (RNAi) technology has shown promise in transgenic mouse models of HD by reducing expression of mutant HTT and slowing disease progression. The advancement of RNAi therapies to human clinical trials is hampered by problems delivering RNAi to affected neurons in a robust and sustainable manner. Mesenchymal stem cells (MSC) have demonstrated a strong safety profile in both completed and numerous ongoing clinical trials. MSC exhibit a number of innate therapeutic effects, such as immune system modulation, homing to injury, and cytokine release into damaged microenvironments. The ability of MSC to transfer larger molecules and even organelles suggested their potential usefulness as delivery vehicles for therapeutic RNA inhibition. In a series of model systems we have found evidence that MSC can transfer RNAi targeting both reporter genes and mutant huntingtin in neural cell lines. MSC expressing shRNA antisense to GFP were found to decrease expression of GFP in SH-SY5Y cells after co-culture when assayed by flow cytometry. Additionally MSC expressing shRNA antisense to HTT were able to decrease levels of mutant HTT expressed in both U87 and SH-SY5Y target cells when assayed by Western blot and densitometry. These results are encouraging for expanding the therapeutic abilities of both RNAi and MSC for future treatments of Huntington's disease.
The chemical composition of persistent organic pollutants (POPs) in the environment is not uniform throughout the world, and these contaminants contain many structurally different lipophilic compounds. In a well-defined study cohort in the Slovak Republic, the POP chemicals present in the peripheral blood of exposed children were chemically analyzed. The chemical analysis data revealed that the relative concentration and profile of structurally different organic pollutants, including polychlorinated biphenyls (PCBs), 2,2'-bis(4-chlorophenyl)-1,1-dichloroethylene (p,p'-DDE), 2,2'-bis(4-chlorophenyl)-1,1,1-trichloro-ethane (p,p'-DDT), hexachlorobenzene (HCB) and β-hexachlorocyclohexane (β-HCH), may vary from individual to individual, even within the same exposure area. These chemicals can be broadly classified into two groups. The first group, the PCB congeners, primarily originated from industrial compounds and their byproducts. The second group of compounds originated from or was commonly used in the agricultural sector (e.g., DDT, HCB). The objective of this study was to examine the effects of the two POP exposure profiles on gene expression. For the study population, we selected pre-pubertal girls (mean age of 46.2±1.4 months) with high POP concentrations in their blood (>75% tile of total POP) and classified them in the high 'PCB' group when the total PCB concentration was significantly higher than the total concentration of other POP components and in the 'Other Than PCB' (OTP) group, when the total PCB concentration was significantly lower than the concentration of the other major POP constituents. A matched control group of girls (<25% tile of total POP) was selected for comparison purpose (n=5 per group). Our aims were to determine whether there were any common effects of high POP exposure at a toxicogenomic level and to investigate how exposure may affect physiological functions of the children in two different exposure scenarios. Global gene expression analysis using a microarray (Affymetrix Gene Chip Human genome U133 Plus 2.0 Array) platform was conducted on the total RNA of peripheral blood mononuclear cells from the girls. The results were analyzed by Partek GS, Louis, MI, which identified twelve genes (ATAD2B, BIVM, CD96, CXorf39, CYTH1 ETNK1, FAM13A, HIRA, INO80B, ODG1, RAD23B, and TSGA14) and two unidentified probe sets, as regulated differentially in both the PCB and OTP groups against the control group. The qRT-PCR method was used to validate the microarray results. The Ingenuity Pathway Analysis (IPA) software package identified the possible molecular impairments and disease risks associated with each gene set. Connective tissue disorders, genetic disorders, skeletal muscular disorders and neurological diseases were associated with the 12 common genes. The data therefore identified the potential molecular effects of POP exposure on a genomic level. This report underscores the importance of further study to validate the results in a random population and to evaluate the use of the identified genes as biomarkers for POP exposure.
Myostatin (MSTN) is a negative regulator of skeletal muscle growth and development. There are two types of MSTNs in fish, but little is known about their gene regulation. Here, the 5' flanking fragments of 1029 bp from MSTN-1 and 643 bp from MSTN-2 were cloned, sequenced, and analyzed in Larimichthys crocea. Both fragments contained CAAT box and several putative cis-regulatory elements. However, putative TATA box, MyoD, MEF3, SP1, USF, and GH-CSE sites were identified only in the L. crocea MSTN-1 (lcMSTN-1) promoter. Transcriptional activities of four fragments (1013, 841, 514, and 261 bp) truncated from lcMSTN-1 upstream region and two fragments (643 and 296 bp) from lcMSTN-2 upstream region were examined in vitro, using transient transfection in CIK and L6 cells. In CIK cells, the promoter activity correlated positively with the length of truncated fragments in both MSTN-1 and 2. The lcMSTN-2 promoter showed a higher activity than lcMSTN-1 in the corresponding region, which was consistent with MSTN gene expression in vivo. In L6 cells, lcMSTN-2 upstream showed an extremely high luciferase activity. These data indicated that both cloned 5' flanking sequences contained functional promoters, and that transcription regulation of lcMSTN-1 and 2 promoters was significantly different between mammalian and fish cells.
<h4>Background</h4>The liver is the primary site of alcohol metabolism and is highly vulnerable to injuries due to chronic alcohol abuse. Several molecular mechanisms, including oxidative stress and altered cellular metabolism, have been implicated in the development and progression of alcoholic liver disease. We sought to gain further insight into the molecular pathogenesis by studying the effects of ethanol exposure on the global gene expression in HepG2 cells.<h4>Methods</h4>HepG2 cells were cultured in the presence or absence of 75 mM ethanol for 9 days, with fresh media daily. Global gene expression changes were studied using Affymetrix GeneChip(®) Human Exon 1.0 ST Arrays. Gene expression differences were validated for 13 genes by quantitative real-time RT-PCR. To identify biological pathways affected by ethanol treatment, differentially expressed genes were analyzed by Ingenuity Pathway Analysis software.<h4>Results</h4>Long-term ethanol exposure altered the expression of 1,093 genes (false discovery rate ≤ 3%); many of these changes were modest. Long-term ethanol exposure affected several pathways, including acute phase response, amino acid metabolism, carbohydrate metabolism, and lipid metabolism.<h4>Conclusions</h4>Global measurements of gene expression show that a large number of genes are affected by chronic ethanol, although most show modest effect. These data provide insight into the molecular pathology resulting from extended alcohol exposure.
Also flagged:nephrogenic systemic fibrosisgadoliniumchronic renal diseasehypothyroidismalbuminNephrogenic sclerosing fibrosis
Journal Article2011-12-07✓ 1 SnippetAggarwal A, Froehlich AA, Essah P, Brinster N, High WA, Downs RW.
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…heart failure, andhemochromatosis.…
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<h4>Introduction</h4>Nephrogenic systemic fibrosis is a condition that has recently been recognized in patients with chronic renal disease and is associated with use of gadolinium-based contrast agents of ubiquitous use in magnetic resonance imaging scans. The condition is believed to arise through inadequate renal clearance of the gadolinium-based contrast agents, resulting in bodily deposition of the gadolinium; this is most widely recognized in the skin, but also occurs in other tissues.<h4>Case presentation</h4>We report the case of a 52-year-old Caucasian man with hypothyroidism and chronic renal disease who developed nephrogenic systemic fibrosis upon repeated exposure to gadolinium, and who presented with a subsequent malabsorption of levothyroxine. This malabsorption resolved only partially upon amelioration of other conditions that might contribute to malabsorption, including edema and infectious diarrhea. The presence of gadolinium was quantified in specimens from his gastrointestinal tract. Our patient otherwise demonstrated adequate gastrointestinal nutritive absorption, objectively shown by normal albumin levels, resolution of diarrhea, and maintenance of his bodily weight.<h4>Conclusions</h4>Our observations suggest that nephrogenic systemic fibrosis can also affect tissue of the gastrointestinal tract, potentially contributing to partial malabsorption of levothyroxine in patients with hypothyroidism.
Also flagged:cartilage oligomeric matrix proteinPSACHCOMPdeathchondrosarcomaChop
Journal Article2011-12-07No SnippetsCoustry F, Posey KL, Liu P, Alcorn JL, Hecht JT.
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Mutations in the cartilage oligomeric matrix protein gene (COMP) cause pseudoachondroplasia (PSACH). This dysplasia results from the intracellular retention of mutant COMP protein and premature death of growth-plate chondrocytes. Toward better understanding of these underlying mechanisms, we examined D469del-COMP activation of the unfolded protein response and cell death pathways in rat chondrosarcoma cells. Using an inducible expression system, we examined the effects of D469del-COMP retention after 4 days of mRNA expression and then 5 days without inducing agent. Retention of D469del-COMP stimulated Chop (Ddit3) and Gadd34 (Ppp1r15a) and triggered reactivation of protein translation that exacerbated intracellular retention. High levels of Nox4 and endoplasmic reticulum receptor stress-inducible Ero1β generated reactive oxygen species, causing oxidative stress. Increased expression of Gadd genes and presence of γH2AX indicated that DNA damage was occurring. The presence of cleaved apoptosis inducing factor (tAIF) and the absence of activated caspases indicated that retention of D469del-COMP triggers cell death in chondrocytes by necroptosis, a caspase-independent programmed necrosis. Loss of growth-plate chondrocytes by necroptosis was also found in our pseudoachondroplasia mouse model. These results suggest a model in which D469del-COMP expression induces persistent endoplasmic reticulum stress, oxidative stress, and DNA damage, thus priming chondrocytes for necroptosis. We define for the first time the precise mechanisms underlying D469del-COMP pathology in pseudoachondroplasia and suggest that oxidative stress and AIF may be promising therapeutic targets.
…Wildtype huntingtin (the protein mutated in HD) enhances the PAT activity of HIP14 and mutant HTT interacts less with HIP14.…
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Post-translational modification of proteins by the lipid palmitate is critical for protein localization and function. Palmitoylation is regulated by the opposing enzymes palmitoyl acyltransferases (PATs) and acyl protein thioesterases, which add and remove palmitate from proteins, respectively. Palmitoylation is particularly important for a number of processes including neuronal development and synaptic activity in the central nervous system. Dysregulated palmitoylation contributes to neuropsychiatric disease. In total six PATs (HIP14, HIP14L, ZDHHC8, ZDHHC9, ZDHHC12, and ZDHHC15) and one thioesterase (PPT1) have been implicated in Huntington disease (HD), Alzheimer disease, schizophrenia, mental retardation, and infantile and adult onset forms of neuronal ceroid lipofuscinosis. Currently there is no genetic link between PATs and Alzheimer disease pathogenesis but palmitoylation of amyloid precursor protein-processing enzyme, γ-secretase, influences β-amyloid generation. Several lines of evidence point to a role for palmitoylation by HIP14 in the pathogenesis of HD; HIP14 is dysfunctional in the presence of the HD mutation and Hip14-deficient mice develop features of HD. Wildtype huntingtin (the protein mutated in HD) enhances the PAT activity of HIP14 and mutant HTT interacts less with HIP14. Therefore, it may be that loss of the positive modulation of HIP14 activity due to reduced interaction with huntingtin is important in the disease mechanism. Preliminary evidence suggests a closely related PAT to HIP14, HIP14L, may also play a role in the pathogenesis of HD. In order to design rational therapeutic approaches to restore palmitoylation in neuropsychiatric disease, it will be critical to better understand the relationships between PATs and thioesterases with their regulators and substrates.
Also flagged:hypomethylationchromatingene silencingcancercancershypermethylation
Journal Article2011-12-07✓ 2 SnippetsHon GC, Hawkins RD, Caballero OL, Lo C, Lister R, Pelizzola M, Valsesia A, Ye Z, Kuan S, Edsall LE, Camargo AA, Stevenson BJ, Ecker JR, Bafna V, Strausberg RL, Simpson AJ, Ren B.
In-Text Gene Mentions
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…NEGR1…
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…DCC…
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While genetic mutation is a hallmark of cancer, many cancers also acquire epigenetic alterations during tumorigenesis including aberrant DNA hypermethylation of tumor suppressors, as well as changes in chromatin modifications as caused by genetic mutations of the chromatin-modifying machinery. However, the extent of epigenetic alterations in cancer cells has not been fully characterized. Here, we describe complete methylome maps at single nucleotide resolution of a low-passage breast cancer cell line and primary human mammary epithelial cells. We find widespread DNA hypomethylation in the cancer cell, primarily at partially methylated domains (PMDs) in normal breast cells. Unexpectedly, genes within these regions are largely silenced in cancer cells. The loss of DNA methylation in these regions is accompanied by formation of repressive chromatin, with a significant fraction displaying allelic DNA methylation where one allele is DNA methylated while the other allele is occupied by histone modifications H3K9me3 or H3K27me3. Our results show a mutually exclusive relationship between DNA methylation and H3K9me3 or H3K27me3. These results suggest that global DNA hypomethylation in breast cancer is tightly linked to the formation of repressive chromatin domains and gene silencing, thus identifying a potential epigenetic pathway for gene regulation in cancer cells.
Type I IFNs are important for direct control of viral infection and generation of adaptive immune responses. Recently, direct stimulation of CD4(+) T cells via type I IFNR has been shown to be necessary for the formation of functional CD4(+) T cell responses. In contrast, we find that CD4(+) T cells do not require intrinsic type I IFN signals in response to combined TLR/anti-CD40 vaccination. Rather, the CD4 response is dependent on the expression of type I IFNR (IFNαR) on innate cells. Further, we find that dendritic cell (DC) expression of the TNF superfamily member OX40 ligand was dependent on type I IFN signaling in the DC, resulting in a reduced CD4(+) T cell response that could be substantially rescued by an agonistic Ab to the receptor OX40. Taken together, we show that the IFNαR dependence of the CD4(+) T cell response is accounted for exclusively by defects in DC activation.
Also flagged:Thy1nephritisAntimesangial proliferative nephritiscell proliferationmetabolism
Journal Article2011-12-07✓ 2 SnippetsLu Y, Liu X, Shi S, Su H, Bai X, Cai G, Yang F, Xie Z, Zhu Y, Zhang Y, Zhang S, Li X, Wang S, Wu D, Zhang L, Wu J, Xie Y, Chen X.
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Abstract)
…MDH1, MPST, NIT2,PRDX6, PSMB7, and TPI1,…
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…PRDX6…
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Anti-Thy1 nephritis is a well-established experimental mesangial proliferative nephritis model. Exploring the molecular mechanisms of pathophysiology in anti-Thy1 nephritis may elucidate the pathogeneses of mesangial proliferation. We examined the roles and acting mechanisms of differentially expressed proteins (DEPs) by bioinformatics analysis of glomeruli proteomic profiles during the course of anti-Thy1 nephritis. In total, 108 DEPs were found by two-dimensional fluorescence difference gel electrophoresis (2D-DIGE), and 40 DEPs were identified by matrix-assisted laser desorption ionization/time of flight and liquid chromatography-MS. DEPs were classified into five clusters (Clusters 1-5), according to their expression trends using Cluster 3.0 software, involved in regulating biological processes such as the stress response, cell proliferation, apoptosis, energy metabolism, transport, and the actin cytoskeleton. The expression patterns of ten DEPs, distributed across five clusters, including AKR1A1, AGAT, ATP6V1B2, HIBADH, MDH1, MPST, NIT2, PRDX6, PSMB7, and TPI1, were validated by Western blotting. Based on Western blotting and immunohistochemistry, we also found that the DEP FHL2, which was primarily expressed in the mesangial region, was down-regulated on days 3 and 5, and up-regulated on day 10. In vitro, we found that FHL2 overexpression induced mesangial cell proliferation by increasing the number of S-phase cells and decreasing G2/M-phase cells, whereas inhibiting FHL2 had the opposite effect. This study explored novel DEPs and their expression patterns during anti-Thy1 nephritis, and elucidated FHL2's effect on mesangial cell proliferation. These results will contribute to our understanding of the pathogenesis of mesangial proliferation.
Also flagged:ischemia-reperfusion injurychemokinesCC motif chemokine receptor 5CCR5kidneyischemia
Journal Article2011-12-07No SnippetsKo GJ, Linfert D, Jang HR, Higbee E, Watkins T, Cheadle C, Liu M, Racusen L, Grigoryev DN, Rabb H.
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Although T cells have been shown to play a direct role in kidney ischemia-reperfusion injury (IRI), little is known about the underlying mechanisms. We hypothesized that studying the transcriptional responses in kidney-infiltrating T cells would help elucidate novel therapeutic targets for kidney IRI. Unilateral renal pedicle clamping for 45 min was performed in male C57BL/6 mice, and CD3(+) T cells were isolated from the kidney and purified. Transcriptional activities of T cell were measured by array-based PCR compared between ischemic kidneys and contralateral nonischemic kidneys. Among total of 89 genes analyzed, 24, 22, 24, and 37 genes were significantly changed at 6 h, day 3, day 10, and day 28 after IRI. Genes associated with cytokines, chemokines, and costimulatory molecules were upregulated. Pathway analysis identified CC motif chemokine receptor 5 (CCR5) as a candidate pathophysiological pathway. CCR5 upregulation was validated at the protein level, and CCR5 blockade improved renal function after kidney IRI. Using discovery techniques to identify transcriptional responses in purified kidney-infiltrating cells enabled the elucidation of novel mechanisms and therapeutic targets for IRI.
Also flagged:urge incontinenceoveractive bladderidiopathic overactive bladderstress incontinenceidiopathicresiniferatoxin
Journal Article2011-12-07No SnippetsDuthie JB, Vincent M, Herbison GP, Wilson DI, Wilson D.
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<h4>Background</h4>Overactive bladder syndrome (OAB) is a common condition with a significant negative impact on quality of life characterised by urgency with or without urge incontinence, frequency and nocturia. Intravesical botulinum toxin is being increasingly used to treat severe overactive bladder refractory to standard management. An increasing body of literature is forming that supports this technique as effective, well tolerated, and safe. This review is a substantial update of the 2007 review of the same title.<h4>Objectives</h4>The objective was to compare intravesical botulinum toxin with other treatments for neurogenic and idiopathic overactive bladder in adults. The hypothesis to be addressed were whether intravesical injection of botulinum toxin was better than placebo or no treatment; pharmacological and other non-pharmacological interventions; whether higher doses of botulinum toxin were better than lower doses; whether botulinum toxin in combination with other treatments was better than other treatments alone; whether one formulation of botulinum toxin is better than another; and whether one injection technique was better than another.<h4>Search methods</h4>We searched the Cochrane Incontinence Group Specialised Trials Register (searched 23 February 2010). The Register contains trials identified from MEDLINE, CINAHL, the Cochrane Central Register of Controlled Trials (CENTRAL), and handsearching of journals and conference proceedings. Additionally, all reference lists of selected trials and relevant review papers were searched. No limitations were placed on the searches.<h4>Selection criteria</h4>All randomised or quasi-randomised controlled trials of treatment for OAB in adults in which at least one management arm involved intravesical injection of botulinum toxin were included. Participants had either neurogenic OAB or idiopathic OAB with or without stress incontinence. Comparison interventions could include no intervention, placebo, lifestyle modification, bladder retraining, pharmacological treatments, surgery, bladder instillation techniques, neuromodulation, and different types, doses, and injection techniques of botulinum toxin.<h4>Data collection and analysis</h4>Binary outcomes were presented as relative risk and continuous outcomes by mean differences. Little data could be synthesised across studies due to differing study designs and outcome measures. Where applicable standard deviations were calculated from P values according to the formula described in section 7.7.3.3 of the Cochrane Handbook of Systematic Reviews of Interventions. Data were tabulated where possible with results taken from trial reports where this was not possible. Where multiple publications were found, the reports were treated as a single source of data.<h4>Main results</h4>Nineteen studies were identified that met the inclusion criteria. Most patients in the studies had neurogenic OAB, but some included patients with idiopathic OAB. All studies demonstrated superiority of botulinum toxin to placebo. Lower doses of botulinum toxin (100 to 150 U) appeared to have beneficial effects, but larger doses (300 U) may have been more effective and longer lasting, but with more side effects. Suburothelial injection had comparable efficacy to intradetrusor injection. The effect of botulinum toxin may last for a number of months and is dependent upon dose and type of toxin used. Patients receiving repeated doses do not seem to become refractory to botulinum toxin. Botulinum toxin appeared to have beneficial effects in OAB that quantitatively exceeded the effects of intravesical resiniferatoxin. Intravesical botulinum toxin appeared to be reasonably safe; however, one study was halted due to a perceived unacceptable rate of urinary retention. <h4>Authors' conclusions</h4>Intravesical botulinum toxin appears to be an effective therapy for refractory OAB symptoms, but as yet little controlled trial data exist on benefits and safety compared with other interventions, or with placebo. Further robust data are required on long term outcomes, safety, and optimal dose of botulinum toxin for OAB.
Also flagged:HDbehavioralHuntington's diseaseneurodegenerative disorderchromosomepolyglutamine
Journal Article2011-12-07✓ 3 SnippetsCowin RM, Bui N, Graham D, Green JR, Grueninger S, Yuva-Paylor LA, Syed AU, Weiss A, Paylor R.
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In the present study we report on the use of speed congenics to generate a C57BL/6J congenic line of HD-model R6/2 mice carrying 110 CAG repeats, which uniquely exhibits minimal intergenerational instability. We also report the first identification of the R6/2 transgene insertion site. The relatively stable line of 110 CAG R6/2 mice was characterized for the onset of behavioral impairments in motor, cognitive and psychiatric-related phenotypes as well as the progression of disease-related impairments from 4 to 10 weeks of age. 110Q mice exhibited many of the phenotypes commonly associated with the R6/2 model including reduced activity and impairments in rotarod performance. The onset of many of the phenotypes occurred around 6 weeks and was progressive across age. In addition, some phenotypes were observed in mice as early as 4 weeks of age. The present study also reports the onset and progression of changes in several molecular phenotypes in the novel R6/2 mice and the association of these changes with behavioral symptom onset and progression. Data from TR-FRET suggest an association of mutant protein state changes (soluble versus aggregated) in disease onset and progression.
Post-transcriptional regulation of gene expression by RNA-binding proteins has pivotal roles in many biological processes. We have shown that Stau1, a conserved RNA-binding protein, negatively regulates myogenesis in C2C12 myoblasts. However, its target mRNAs in regulation of myogenesis remain unknown. Here we describe that Stau1 positively regulates expression of Dvl2 gene encoding a central mediator of Wnt pathway in undifferentiated C2C12 myoblasts. Stau1 binds to 3' untranslated region (UTR) of Dvl2 mRNA and Stau1 knockdown shortened a half-life of the mRNA containing Dvl2 3' UTR. After induction of myogenic differentiation, association of Stau1 with 3' UTR of Dvl2 mRNA was decreased. Correlated with the decrease in the association, the Dvl2 mRNA level was reduced during myogenesis. A forced expression of Dvl2 markedly inhibited progression of myogenic differentiation. Our results suggest that Dvl2 has an inhibitory role in myogenesis and Stau1 coordinates myogenesis through the regulation of Dvl2 mRNA.
Also flagged:pathogenesistranslationalcreatinineureanitrogenAcute Kidney Injury
Journal Article2011-12-07No SnippetsZarjou A, Sanders PW, Mehta RL, Agarwal A.
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Acute kidney injury (AKI) is a common, heterogeneous, and detrimental clinical condition that has significant attributable morbidity and mortality. Despite major advances in understanding the epidemiology, pathogenesis, and outcomes of AKI, preventive measures remain inadequate and therapeutic approaches (except for renal replacement therapy) have largely proven futile so far. Critical to the process of designing rational therapies is translational research, which involves the transition between the basic research discoveries and everyday clinical applications to prevent, diagnose, and treat human diseases. Progress in innovative approaches has been hampered due in part to the reliance on functional markers (serum creatinine and blood urea nitrogen) that are neither sensitive nor specific to diagnose AKI. This limitation has created a great deal of interest and intense investigation to identify a "troponin-like marker" that would facilitate recognition of AKI and allow for timely implementation of the precise therapeutic agent. The other major obstacle in this field is the diverse and complex nature of AKI that involves multiple independent and overlapping pathways, making it difficult to cure AKI with a single approach. In this review, we will summarize the advances, ongoing studies, and future perspectives in the field of translational research of AKI.
Also flagged:nonalcoholic fatty liver diseaseNAFLDironNASHhepatic fibrosisALT
Journal Article2011-12-06✓ 2 SnippetsKowdley KV, Belt P, Wilson LA, Yeh MM, Neuschwander-Tetri BA, Chalasani N, Sanyal AJ, Nelson JE, NASH Clinical Research Network.
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<h4>Unlabelled</h4>Serum ferritin (SF) levels are commonly elevated in patients with nonalcoholic fatty liver disease (NAFLD) because of systemic inflammation, increased iron stores, or both. The aim of this study was to examine the relationship between elevated SF and NAFLD severity. Demographic, clinical, histologic, laboratory, and anthropometric data were analyzed in 628 adult patients with NAFLD (age, ≥ 18 years) with biopsy-proven NAFLD and an SF measurement within 6 months of their liver biopsy. A threshold SF >1.5 × upper limit of normal (ULN) (i.e., >300 ng/mL in women and >450 ng/mL in men) was significantly associated with male sex, elevated serum alanine aminotransferase, aspartate aminotransferase, iron, transferrin-iron saturation, iron stain grade, and decreased platelets (P < 0.01). Histologic features of NAFLD were more severe among patients with SF >1.5 × ULN, including steatosis, fibrosis, hepatocellular ballooning, and diagnosis of NASH (P < 0.026). On multiple regression analysis, SF >1.5 × ULN was independently associated with advanced hepatic fibrosis (odds ratio [OR], 1.66; 95% confidence interval [CI], 1.05-2.62; P = 0.028) and increased NAFLD Activity Score (NAS) (OR, 1.99; 95% CI, 1.06-3.75; P = 0.033).<h4>Conclusions</h4>A SF >1.5 × ULN is associated with hepatic iron deposition, a diagnosis of NASH, and worsened histologic activity and is an independent predictor of advanced hepatic fibrosis among patients with NAFLD. Furthermore, elevated SF is independently associated with higher NAS, even among patients without hepatic iron deposition. We conclude that SF is useful to identify NAFLD patients at risk for NASH and advanced fibrosis.
Also flagged:anxietydepressionmajor depressionSerotoninmajor depressive disordersertraline
Journal Article2011-12-06No SnippetsGollan JK, Fava M, Kurian B, Wisniewski SR, Rush AJ, Daly E, Miyahara S, Trivedi MH.
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<h4>Objective</h4>To evaluate the prevalence of new onset or worsening of anxiety symptoms, as well as their clinical implications, during the first 2 weeks of Selective Serotonin Reuptake Inhibitor (SSRI) pharmacotherapy for depression.<h4>Method</h4>Adult outpatients with nonpsychotic major depressive disorder were enrolled in an 8-week acute phase SSRI treatment trial at 15 clinical sites across the United States. Worsening anxiety was defined as a greater than 2-point increase on the Beck Anxiety Inventory (BAI) between baseline and Week 2. New onset of anxiety symptoms was ascribed when the BAI baseline rating was 0 and the Week 2 value was greater or equal to 2 points on the BAI.<h4>Results</h4>Overall, after 2 weeks of treatment, 48.8% (98 of 201 participants) reported improvement in anxiety symptoms, 36.3% (73 of 201) reported minimal symptom change, and 14.9% (30 of 201) reported worsening of anxiety symptoms. No association was found between change in anxiety symptoms within the first 2 weeks and change in depressive symptoms or remission at the end of 8 weeks of treatment. For participants with clinically meaningful anxiety symptoms at baseline, however, worsening of anxiety during the first 2 weeks of treatment was associated with worsening depressive symptoms by 8 weeks (P = .054).<h4>Conclusions</h4>The trajectory of anxiety symptom change early in SSRI treatment is an important indicator of eventual outcome for outpatients with major depression and baseline anxiety symptoms.
Also flagged:TDP-438-Hydroxyquinolinesα-SynucleinBEM38-hydroxyquinolineBCK2
Journal Article2011-12-06✓ 5 SnippetsTardiff DF, Tucci ML, Caldwell KA, Caldwell GA, Lindquist S.
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No current therapies target the underlying cellular pathologies of age-related neurodegenerative diseases. Model organisms provide a platform for discovering compounds that protect against the toxic, misfolded proteins that initiate these diseases. One such protein, TDP-43, is implicated in multiple neurodegenerative diseases, including amyotrophic lateral sclerosis and frontotemporal lobar degeneration. In yeast, TDP-43 expression is toxic, and genetic modifiers first discovered in yeast have proven to modulate TDP-43 toxicity in both neurons and humans. Here, we describe a phenotypic screen for small molecules that reverse TDP-43 toxicity in yeast. One group of hit compounds was 8-hydroxyquinolines (8-OHQ), a class of clinically relevant bioactive metal chelators related to clioquinol. Surprisingly, in otherwise wild-type yeast cells, different 8-OHQs had selectivity for rescuing the distinct toxicities caused by the expression of TDP-43, α-synuclein, or polyglutamine proteins. In fact, each 8-OHQ synergized with the other, clearly establishing that they function in different ways. Comparative growth and molecular analyses also revealed that 8-OHQs have distinct metal chelation and ionophore activities. The diverse bioactivity of 8-OHQs indicates that altering different aspects of metal homeostasis and/or metalloprotein activity elicits distinct protective mechanisms against several neurotoxic proteins. Indeed, phase II clinical trials of an 8-OHQ has produced encouraging results in modifying Alzheimer disease. Our unbiased identification of 8-OHQs in a yeast TDP-43 toxicity model suggests that tailoring 8-OHQ activity to a particular neurodegenerative disease may be a viable therapeutic strategy.
Also flagged:growth coneaxonsdendritesguidance moleculesadhesion proteinsneurotrophic factors
Journal Article2011-12-06✓ 1 SnippetDeinhardt K, Kim T, Spellman DS, Mains RE, Eipper BA, Neubert TA, Chao MV, Hempstead BL.
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Growth of axons and dendrites is a dynamic process that involves guidance molecules, adhesion proteins, and neurotrophic factors. Although neurite extension is stimulated by the neurotrophin nerve growth factor (NGF), we found that the precursor of NGF, proNGF, induced acute collapse of growth cones of cultured hippocampal neurons. This retraction was initiated by an interaction between the p75 neurotrophin receptor (p75NTR) and the sortilin family member SorCS2 (sortilin-related VPS10 domain-containing receptor 2). Binding of proNGF to the p75NTR-SorCS2 complex induced growth cone retraction by initiating the dissociation of the guanine nucleotide exchange factor Trio from the p75NTR-SorCS2 complex, resulting in decreased Rac activity and, consequently, growth cone collapse. The actin-bundling protein fascin was also inactivated, contributing to the destabilization and collapse of actin filaments. These results identify a bifunctional signaling mechanism by which proNGF regulates actin dynamics to acutely modulate neuronal morphology.
Dynamic expansions of toxic polyglutamine (polyQ)-encoding CAG repeats in ubiquitously expressed, but otherwise unrelated, genes cause a number of late-onset progressive neurodegenerative disorders, including Huntington disease and the spinocerebellar ataxias. As polyQ toxicity in these disorders increases with repeat length, the intergenerational expansion of unstable CAG repeats leads to anticipation, an earlier age-at-onset in successive generations. Crucially, disease associated alleles are also somatically unstable and continue to expand throughout the lifetime of the individual. Interestingly, the inherited polyQ length mediating a specific age-at-onset of symptoms varies markedly between disorders. It is widely assumed that these inter-locus differences in polyQ toxicity are mediated by protein context effects. Previously, we demonstrated that the tendency of expanded CAG•CTG repeats to undergo further intergenerational expansion (their 'expandability') also differs between disorders and these effects are strongly correlated with the GC content of the genomic flanking DNA. Here we show that the inter-locus toxicity of the expanded polyQ tracts of these disorders also correlates with both the expandability of the underlying CAG repeat and the GC content of the genomic DNA flanking sequences. Inter-locus polyQ toxicity does not correlate with properties of the mRNA or protein sequences, with polyQ location within the gene or protein, or steady state transcript levels in the brain. These data suggest that the observed inter-locus differences in polyQ toxicity are not mediated solely by protein context effects, but that genomic context is also important, an effect that may be mediated by modifying the rate at which somatic expansion of the DNA delivers proteins to their cytotoxic state.
Also flagged:bisphosphonatesSkeletal diseasesbone diseasesosteoporosiswound healinghydrazine
Journal Article2011-12-05No SnippetsYewle JN, Puleo DA, Bachas LG.
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Skeletal diseases have a major impact on the worldwide population and economy. Although several therapeutic agents and treatments are available for addressing bone diseases, they are not being fully utilized because of their uptake in nontargeted sites and related side effects. Active targeting with controlled delivery is an ideal approach for treatment of such diseases. Because bisphosphonates are known to have high affinity to bone and are being widely used in treatment of osteoporosis, they are well-suited for drug targeting to bone. In this study, a targeted delivery of therapeutic agent to resorption sites and wound healing sites of bone was explored. Toward this goal, bifunctional hydrazine-bisphosphonates (HBPs), with spacers of various lengths, were synthesized and studied for their enhanced affinity to bone. Crystal growth inhibition studies showed that these HBPs have high affinity to hydroxyapatite, and HBPs with shorter spacers bind more strongly than alendronate to hydroxyapatite. The HBPs did not affect proliferation of MC3T3-E1 preosteoblasts, did not induce apoptosis, and were not cytotoxic at the concentration range tested (10(-6)-10(-4) M). Furthermore, drugs can be linked to the HBPs through a hydrazone linkage that is cleavable at the low pH of bone resorption and wound healing sites, leading to release of the drug. This was demonstrated using hydroxyapatite as a model material of bone and 4-nitrobenzaldehyde as a model drug. This study suggests that these HBPs could be used for targeted delivery of therapeutic agents to bone.
Also flagged:spermatogenesismale infertilitychromosomeInfertilityazoospermiaoligozoospermia
Journal Article2011-12-05No SnippetsMassart A, Lissens W, Tournaye H, Stouffs K.
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Approximately 10%-15% of couples are infertile, and a male factor is involved in almost half of these cases. This observation is due in part to defects in spermatogenesis, and the underlying causes, including genetic abnormalities, remain largely unknown. Until recently, the only genetic tests used in the diagnosis of male infertility were aimed at detecting the presence of microdeletions of the long arm of the Y chromosome and/or chromosomal abnormalities. Various other single-gene or polygenic defects have been proposed to be involved in male fertility. However, their causative effects often remain unproven. The recent evolution in the development of whole-genome-based techniques and the large-scale analysis of mouse models might help in this process. Through knockout mouse models, at least 388 genes have been shown to be associated with spermatogenesis in mice. However, problems often arise when translating this information from mice to humans.
Also flagged:AcetyltransferaseING tumor suppressor proteinshistone H3lysinemethylationING4
Journal Article2011-12-05No SnippetsAvvakumov N, Lalonde ME, Saksouk N, Paquet E, Glass KC, Landry AJ, Doyon Y, Cayrou C, Robitaille GA, Richard DE, Yang XJ, Kutateladze TG, Côté J.
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Acetyltransferase complexes of the MYST family with distinct substrate specificities and functions maintain a conserved association with different ING tumor suppressor proteins. ING complexes containing the HBO1 acetylase are a major source of histone H3 and H4 acetylation in vivo and play critical roles in gene regulation and DNA replication. Here, our molecular dissection of HBO1/ING complexes unravels the protein domains required for their assembly and function. Multiple PHD finger domains present in different subunits bind the histone H3 N-terminal tail with a distinct specificity toward lysine 4 methylation status. We show that natively regulated association of the ING4/5 PHD domain with HBO1-JADE determines the growth inhibitory function of the complex, linked to its tumor suppressor activity. Functional genomic analyses indicate that the p53 pathway is a main target of the complex, at least in part through direct transcription regulation at the initiation site of p21/CDKN1A. These results demonstrate the importance of ING association with MYST acetyltransferases in controlling cell proliferation, a regulated link that accounts for the reported tumor suppressor activities of these complexes.
Also flagged:nucleosomeMethyl-CpG-binding protein 2chromatin-binding proteinbindingchromatinmethylation
Journal Article2011-12-05✓ 1 SnippetThambirajah AA, Ng MK, Frehlick LJ, Li A, Serpa JJ, Petrotchenko EV, Silva-Moreno B, Missiaen KK, Borchers CH, Adam Hall J, Mackie R, Lutz F, Gowen BE, Hendzel M, Georgel PT, Ausió J.
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Methyl-CpG-binding protein 2 (MeCP2) is a chromatin-binding protein that mediates transcriptional regulation, and is highly abundant in brain. The nature of its binding to reconstituted templates has been well characterized in vitro. However, its interactions with native chromatin are less understood. Here we show that MeCP2 displays a distinct distribution within fractionated chromatin from various tissues and cell types. Artificially induced global changes in DNA methylation by 3-aminobenzamide or 5-aza-2'-deoxycytidine, do not significantly affect the distribution or amount of MeCP2 in HeLa S3 or 3T3 cells. Most MeCP2 in brain is chromatin-bound and localized within highly nuclease-accessible regions. We also show that, while in most tissues and cell lines, MeCP2 forms stable complexes with nucleosome, in brain, a fraction of it is loosely bound to chromatin, likely to nucleosome-depleted regions. Finally, we provide evidence for novel associations of MeCP2 with mononucleosomes containing histone H2A.X, H3K9me(2) and H3K27me(3) in different chromatin fractions from brain cortex and in vitro. We postulate that the functional compartmentalization and tissue-specific distribution of MeCP2 within different chromatin types may be directed by its association with nucleosomes containing specific histone variants, and post-translational modifications.
Journal Article2011-12-05No SnippetsXiao X, Gong W, Demirci G, Liu W, Spoerl S, Chu X, Bishop DK, Turka LA, Li XC.
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OX40 is a T cell costimulatory molecule that belongs to the TNFR superfamily. In the absence of immune activation, OX40 is selectively expressed by Foxp3(+) regulatory T cells (Tregs), but not by resting conventional T cells. The exact role of OX40 in Treg homeostasis and function remains incompletely defined. In this study, we demonstrate that OX40 engagement in vivo in naive mice induces initial expansion of Foxp3(+) Tregs, but the expanded Tregs have poor suppressive function and exhibit features of exhaustion. We also show that OX40 enables the activation of the Akt and Stat5 pathways in Tregs, resulting in transient proliferation of Tregs and reduced levels of Foxp3 expression. This creates a state of relative IL-2 deficiency in naive mice that further impacts Tregs. This exhausted Treg phenotype can be prevented by exogenous IL-2, as both OX40 and IL-2 agonists drive further expansion of Tregs in vivo. Importantly, Tregs expanded by both OX40 and IL-2 agonists are potent suppressor cells, and in a heart transplant model, they promote long-term allograft survival. Our data reveal a novel role for OX40 in promoting immune tolerance and may have important clinical implications.
Also flagged:canceresterasemembraneCalcein-AMnucleusdeath
Journal Article2011-12-05✓ 5 SnippetsGilbert DF, Erdmann G, Zhang X, Fritzsche A, Demir K, Jaedicke A, Muehlenberg K, Wanker EE, Boutros M.
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…We have generated stably transfected human HEK293 T-Rex cell lines that upon tetracycline-induction conditionally express Huntingtin poly Q tract of 23 (HTT-Q23, wild type) and poly Q tract of 79 (HTT-Q79, mutant), respectively [14].…
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…For generation of stable, tetracycline-inducible HEK-293 cell lines (Invitrogen), Huntingtin poly Q tract of 23 (HTT-Q23, wild type) and poly Q tract of 79 (HTT-Q79, mutant) proteins were subcloned into a gateway compatible pcDNA5/FRT/TO vector, according to the manual of the Flp-In system (Invitrogen) and as reported in [14].…
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…To identify genes relevant to HD from the proof-of-principle study we identified siRNAs which showed strong cell fitness effects in the Huntingtin mutant cell line (HTT-Q79) but not in wild type cells (HTT-Q23).…
Cell-based high-throughput RNAi screening has become a powerful research tool in addressing a variety of biological questions. In RNAi screening, one of the most commonly applied assay system is measuring the fitness of cells that is usually quantified using fluorescence, luminescence and absorption-based readouts. These methods, typically implemented and scaled to large-scale screening format, however often only yield limited information on the cell fitness phenotype due to evaluation of a single and indirect physiological indicator. To address this problem, we have established a cell fitness multiplexing assay which combines a biochemical approach and two fluorescence-based assaying methods. We applied this assay in a large-scale RNAi screening experiment with siRNA pools targeting the human kinome in different modified HEK293 cell lines. Subsequent analysis of ranked fitness phenotypes assessed by the different assaying methods revealed average phenotype intersections of 50.7±2.3%-58.7±14.4% when two indicators were combined and 40-48% when a third indicator was taken into account. From these observations we conclude that combination of multiple fitness measures may decrease false-positive rates and increases confidence for hit selection. Our robust experimental and analytical method improves the classical approach in terms of time, data comprehensiveness and cost.
Journal Article2011-12-04No SnippetsElia J, Glessner JT, Wang K, Takahashi N, Shtir CJ, Hadley D, Sleiman PM, Zhang H, Kim CE, Robison R, Lyon GJ, Flory JH, Bradfield JP, Imielinski M, Hou C, Frackelton EC, Chiavacci RM, Sakurai T, Rabin C, Middleton FA, Thomas KA, Garris M, Mentch F, Freitag CM, Steinhausen HC, Todorov AA, Reif A, Rothenberger A, Franke B, Mick EO, Roeyers H, Buitelaar J, Lesch KP, Banaschewski T, Ebstein RP, Mulas F, Oades RD, Sergeant J, Sonuga-Barke E, Renner TJ, Romanos M, Romanos J, Warnke A, Walitza S, Meyer J, Pálmason H, Seitz C, Loo SK, Smalley SL, Biederman J, Kent L, Asherson P, Anney RJ, Gaynor JW, Shaw P, Devoto M, White PS, Grant SF, Buxbaum JD, Rapoport JL, Williams NM, Nelson SF, Faraone SV, Hakonarson H.
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Attention deficit hyperactivity disorder (ADHD) is a common, heritable neuropsychiatric disorder of unknown etiology. We performed a whole-genome copy number variation (CNV) study on 1,013 cases with ADHD and 4,105 healthy children of European ancestry using 550,000 SNPs. We evaluated statistically significant findings in multiple independent cohorts, with a total of 2,493 cases with ADHD and 9,222 controls of European ancestry, using matched platforms. CNVs affecting metabotropic glutamate receptor genes were enriched across all cohorts (P = 2.1 × 10(-9)). We saw GRM5 (encoding glutamate receptor, metabotropic 5) deletions in ten cases and one control (P = 1.36 × 10(-6)). We saw GRM7 deletions in six cases, and we saw GRM8 deletions in eight cases and no controls. GRM1 was duplicated in eight cases. We experimentally validated the observed variants using quantitative RT-PCR. A gene network analysis showed that genes interacting with the genes in the GRM family are enriched for CNVs in ∼10% of the cases (P = 4.38 × 10(-10)) after correction for occurrence in the controls. We identified rare recurrent CNVs affecting glutamatergic neurotransmission genes that were overrepresented in multiple ADHD cohorts.
Huntington's disease (HD) is a genetic, degenerative, and progressive central nervous system disease. It is characterized by motor abnormalities and cognitive and psychiatric symptoms. Objective. To describe the precise degree of clinical severity of patients with HD through a new neurocognitive assessment. Methods. Unprecedented battery of computerized tests, CNSVS (Central Nervous System Vital Signs), was applied at three different moments in 2008, 2009, and 2010. The accurate and reliable CNSVS objectively provided the cognitive state of patients and allowed for the evaluation of disease progression. Case Report. P., 26, female, without any medication, with normal psychomotor development is a parent carrier of HD. In 2008, she was diagnosed with HD in accordance with the Medical Genetics Laboratories. Conclusion. The tests may be useful to reveal the exact measure of the current evolutionary stage of HD patients, allowing for more efficient planning of treatment and future procedures, such as the medication, therapy, and physical activity to be administered.
Progenitor and pluripotent cell types offer promise as regenerative therapies but transfecting these sensitive cells has proven difficult. Herein, a series of linear trehalose-oligoethyleneamine "click" copolymers were synthesized and examined for their ability to deliver plasmid DNA (pDNA) to two progenitor cell types, human dermal fibroblasts (HDFn) and rat mesenchymal stem cells (RMSC). Seven polymer vehicle analogs were synthesized in which three parameters were systematically varied: the number of secondary amines (4-6) within the polymer repeat unit (Tr4(33), Tr5(30), and Tr6(32)), the end group functionalities [PEG (Tr4(128)PEG-a, Tr4(118)PEG-b), triphenyl (Tr4(107)-c), or azido (Tr4(99)-d)], and the molecular weight (degree of polymerization of about 30 or about 100) and the biological efficacy of these vehicles was compared to three controls: Lipofectamine 2000, JetPEI, and Glycofect. The trehalose polymers were all able to bind and compact pDNA polyplexes, and promote pDNA uptake and gene expression [luciferase and enhanced green fluorescent protein (EGFP)] with these primary cell types and the results varied significantly depending on the polymer structure. Interestingly, in both cell types, Tr4(33) and Tr5(30) yielded the highest luciferase gene expression. However, when comparing the number of cells transfected with a reporter plasmid encoding enhanced green fluorescent protein, Tr4(33) and Tr4(107)-c yielded the highest number of HDFn cells positive for EGFP. Interestingly, with RMSCs, all of the higher molecular weight analogs (Tr4(128)PEG-a, Tr4(118)PEG-b, Tr4(107)-c, Tr4(99)-d) yielded high percentages of cells positive for EGFP (30-40%).
Also flagged:hydroxyapatitedegenerative lumbar spinal disorderhematomainfectioninfectious diseasedegenerative spinal disease
Journal Article2011-12-03No SnippetsKim H, Lee CK, Yeom JS, Lee JH, Lee KH, Chang BS.
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<h4>Objective</h4>To evaluate whether a synthetic bone chip made of porous hydroxyapatite can effectively extend local decompressed bone graft in instrumented posterior lumbar interbody fusion (PLIF).<h4>Methods</h4>130 patients, 165 segments, who had undergone PLIF with cages and instrumentation for single or double level due to degenerative conditions, were investigated retrospectively by independent blinded observer. According to the material of graft, patients were divided into three groups. HA group (19 patients, 25 segments): with hydroxyapatite bone chip in addition to autologous local decompressed bone, IBG group (25 patients, 28 segments): with autologous iliac crest bone graft in addition to local decompressed bone and LB group (86 patients, 112 segments): with local decompressed bone only. Radiologic and clinical outcome were compared among groups and postoperative complications, transfusion, time and cost of operation and duration of hospitalization were also investigated.<h4>Results</h4>Radiologic fusion rate and clinical outcome were not different. Economic cost, transfusion and hospital stay were also similar. But operation time was significantly longer in IBG group than in other groups. There were no lasting complications associated with HA and LB group with contrast to five cases with persisting donor site pain in IBG group.<h4>Conclusion</h4>Porous hydroxyapatite bone chip is a useful bone graft extender in PLIF when used in conjunction with local decompressed bone.
Also flagged:depressionbreast cancerserotonin transporter
Journal Article2011-12-02✓ 2 SnippetsKim KR, Chung HC, Lee E, Kim SJ, Namkoong K.
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…Body image, sexual function and depression in Korean patients with breast cancer: modification by 5-HTT polymorphism.…
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…cancer: modification by5-HTTpolymorphism.…
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<h4>Background</h4>Nearly 50% of women with breast cancer show depressive symptoms after diagnosis and treatment. The purpose of this study was to clarify how psychosocial factors (body image, sexuality, and social relationships) and genetic factors (functional polymorphism of the serotonin transporter-linked promoter region) influence depression.<h4>Methods</h4>The participants were categorized by DSM-IV diagnoses; scored according to their depressive symptoms, body image and social and sexual function (BIRS), self-esteem, and quality of life; and genotyped by functional polymorphism of the serotonin transporter promoter.<h4>Results</h4>Patients with depressive symptoms showed low self-esteem, poor body image, relationship problems, and low quality of life. Genotype frequencies did not differ between two groups categorized by the presence or absence of depressive symptoms. However, the patients with the short allele of the 5-HTTLPR had significantly higher HAM-D scores (F = 7.59, p = 0.047).<h4>Conclusion</h4>The results suggest that psychosocial factors related to breast cancer treatment such as body image, self-esteem, and interpersonal relationship influence the development of depressive symptoms. The 5-HTTLPR may be associated with the severity of depressive symptoms rather than susceptibility to the development of depressive symptoms.
<h4>Background</h4>Sodium channel NaV1.7 is preferentially expressed within dorsal root ganglia (DRG), trigeminal ganglia and sympathetic ganglion neurons and their fine-diamter axons, where it acts as a threshold channel, amplifying stimuli such as generator potentials in nociceptors. Gain-of-function mutations and variants (single amino acid substitutions) of NaV1.7 have been linked to three pain syndromes: Inherited Erythromelalgia (IEM), Paroxysmal Extreme Pain Disorder (PEPD), and Small Fiber Neuropathy (SFN). IEM is characterized clinically by burning pain and redness that is usually focused on the distal extremities, precipitated by mild warmth and relieved by cooling, and is caused by mutations that hyperpolarize activation, slow deactivation, and enhance the channel ramp response. PEPD is characterized by perirectal, periocular or perimandibular pain, often triggered by defecation or lower body stimulation, and is caused by mutations that severely impair fast-inactivation. SFN presents a clinical picture dominated by neuropathic pain and autonomic symptoms; gain-of-function variants have been reported to be present in approximately 30% of patients with biopsy-confirmed idiopathic SFN, and functional testing has shown altered fast-inactivation, slow-inactivation or resurgent current. In this paper we describe three patients who house the NaV1.7/I228M variant.<h4>Methods</h4>We have used clinical assessment of patients, quantitative sensory testing and skin biopsy to study these patients, including two siblings in one family, in whom genomic screening demonstrated the I228M NaV1.7 variant. Electrophysiology (voltage-clamp and current-clamp) was used to test functional effects of the variant channel.<h4>Results</h4>We report three different clinical presentations of the I228M NaV1.7 variant: presentation with severe facial pain, presentation with distal (feet, hands) pain, and presentation with scalp discomfort in three patients housing this NaV1.7 variant, two of which are from a single family. We also demonstrate that the NaV1.7/I228M variant impairs slow-inactivation, and produces hyperexcitability in both trigeminal ganglion and DRG neurons.<h4>Conclusion</h4>Our results demonstrate intra- and interfamily phenotypic diversity in pain syndromes produced by a gain-of-function variant of NaV1.7.
…Participants were individuals without HD but carrying the mutant HTT gene (ie, premanifest HD), patients with early HD, and healthy control individuals matched by age and sex to the combined HD groups.…
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…carrying the mutantHTTgene (ie, premanifest…
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<h4>Background</h4>TRACK-HD is a prospective observational biomarker study in premanifest and early Huntington's disease (HD). In this report we define a battery of potential outcome measures for therapeutic trials.<h4>Methods</h4>We assessed longitudinal data collected at baseline, 12 months, and 24 months at sites in Leiden (Netherlands), London (UK), Paris (France), and Vancouver (Canada). Participants were individuals without HD but carrying the mutant HTT gene (ie, premanifest HD), patients with early HD, and healthy control individuals matched by age and sex to the combined HD groups. Data were collected with 3T MRI, clinical, cognitive, quantitative motor, oculomotor, and neuropsychiatric assessments. We estimated adjusted, between-group differences in rates of change in these measures and concomitant longitudinal effect sizes.<h4>Findings</h4>Longitudinal data were available for 116 control individuals, 117 premanifest gene carriers, and 116 participants with early HD. Significantly greater progressive grey-matter, white-matter, whole-brain, and regional atrophy was recorded in the premanifest and early HD groups than in the control group. Effect sizes for atrophy rates between participants with early HD and controls were largest in the caudate (2·04, 95% CI 1·68 to 2·48) and white matter (1·70, 1·40 to 2·08). Functional, quantitative motor, and cognitive measures deteriorated to a greater extent in the early HD group than in controls, with the largest effect size in the symbol digit modality test (1·00, 0·67 to 1·27). In the early HD group, changes in structural imaging and various cognitive and quantitative motor scores were associated with worsening total motor score (TMS) and total functional capacity (TFC). In the premanifest group, despite significant declines in regional and overall brain volumes, few functional variables showed significant 24 month change compared with controls; TMS, emotion recognition, and speeded tapping were exceptions. Premanifest individuals with progression, predefined as an increase in TMS score of 5 points or more, any TFC decline, or a new diagnostic confidence score of 4, exhibited higher rates of brain atrophy and deterioration on some quantitative motor tasks compared with other premanifest participants.<h4>Interpretation</h4>On the basis of longitudinal effect size, we recommend several objective outcome measures for clinical trials in participants with early HD. Hypothetical treatment effects defined by slower longitudinal changes in these measures would be detectable over a realistic timescale with practical sample sizes. The restricted 24 month cognitive or motor decline in the premanifest sample illustrates the greater challenge in trial design for this group.<h4>Funding</h4>CHDI/HighQ Foundation Inc.
Also flagged:β-amyloidpeptideneurodegenerative disordersAlzheimer diseaseADDNA-PK
Journal Article2011-12-02✓ 1 SnippetCardinale A, Racaniello M, Saladini S, De Chiara G, Mollinari C, de Stefano MC, Pocchiari M, Garaci E, Merlo D.
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Accumulation of DNA damage and deficiency in DNA repair potentially contribute to the progressive neuronal loss in neurodegenerative disorders, including Alzheimer disease (AD). In multicellular eukaryotes, double strand breaks (DSBs), the most lethal form of DNA damage, are mainly repaired by the nonhomologous end joining pathway, which relies on DNA-PK complex activity. Both the presence of DSBs and a decreased end joining activity have been reported in AD brains, but the molecular player causing DNA repair dysfunction is still undetermined. β-Amyloid (Aβ), a potential proximate effector of neurotoxicity in AD, might exert cytotoxic effects by reactive oxygen species generation and oxidative stress induction, which may then cause DNA damage. Here, we show that in PC12 cells sublethal concentrations of aggregated Aβ(25-35) inhibit DNA-PK kinase activity, compromising DSB repair and sensitizing cells to nonlethal oxidative injury. The inhibition of DNA-PK activity is associated with down-regulation of the catalytic subunit DNA-PK (DNA-PKcs) protein levels, caused by oxidative stress and reversed by antioxidant treatment. Moreover, we show that sublethal doses of Aβ(1-42) oligomers enter the nucleus of PC12 cells, accumulate as insoluble oligomeric species, and reduce DNA-PK kinase activity, although in the absence of oxidative stress. Overall, these findings suggest that Aβ mediates inhibition of the DNA-PK-dependent nonhomologous end joining pathway contributing to the accumulation of DSBs that, if not efficiently repaired, may lead to the neuronal loss observed in AD.
…Huntington's disease (HD) is a neurodegenerative genetic disorder caused by an expansion of CAG repeats in the HD gene encoding for huntingtin (Htt), resulting in progressive death of striatal neurons, with clinical symptoms of chorea, dementia and dramatic weight loss.…
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…encoding for huntingtin (Htt), resulting in progressive…
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Huntington's disease (HD) is a neurodegenerative genetic disorder caused by an expansion of CAG repeats in the HD gene encoding for huntingtin (Htt), resulting in progressive death of striatal neurons, with clinical symptoms of chorea, dementia and dramatic weight loss. Metabolic and mitochondrial dysfunction caused by the expanded polyglutamine sequence have been described along with other mechanisms of neurodegeneration previously described in human tissues and animal models of HD. In this review, we focus on mitochondrial and metabolic disturbances affecting both the central nervous system and peripheral cells, including mitochondrial DNA damage, mitochondrial complexes defects, loss of calcium homeostasis and transcriptional deregulation. Glucose abnormalities have also been described in peripheral tissues of HD patients and in HD animal and cellular models. Moreover, there are no effective neuroprotective treatments available in HD. Thus, we briefly discuss the role of creatine and coenzyme Q10 that target mitochondrial dysfunction and impaired bioenergetics and have been previously used in HD clinical trials.
<h4>Introduction</h4>Hepatocellular carcinoma (HCC) is a major cause of cancer worldwide. The vast majority of cases occur in individuals with a chronic HBV or HCV infection. In addition, a number of metabolic diseases of the liver are associated with the development of HCC.<h4>Pathophysiologic mechanisms</h4>The mechanisms responsible for the progression of the metabolic liver disease and HCC differ from those associated with viral liver disease.<h4>Conclusions</h4>The purpose of this report is to describe the mechanisms responsible for the disease progression and HCC in case of metabolic liver disease. A secondary goal is to identify the frequency of HCC development in the disorders described.
Also flagged:PGorganizationaddictionDopamineTestosteroneSerotonin
Journal Article2011-12-01✓ 1 SnippetNussbaum D, Honarmand K, Govoni R, Kalahani-Bargis M, Bass S, Ni X, Laforge K, Burden A, Romero K, Basarke S, Courbasson C, Deamond W.
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Introduction)
…transporter gene (5-HTTLPR) was found…
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Problem Gambling (PG) represents a serious problem for affected individuals, their families and society in general. Previous approaches to understanding PG have been confined to only a subset of the psychobiological factors influencing PG. We present a model that attempts to integrate potential causal factors across levels of organization, providing empirical evidence from the vast literature on PG and complimentary literatures in decision-making and addiction. The model posits that components are arranged systematically to bias decisions in favor of either immediately approaching or avoiding targets affording the opportunity for immediate reward. Dopamine, Testosterone and Endogenous Opioids favor immediate approach, while Serotonin and Cortisol favor inhibition. Glutamate is involved in associative learning between stimuli and promotes the approach response through its link to the DA reward system. GABA functions to monitor performance and curb impulsive decision-making. Finally, while very high levels of Norepinephrine can induce arousal to an extent that is detrimental to sound decision-making, the reactivity of the Norepinephrine system and its effects of Cortisol levels can shift the focus towards long-term consequences, thereby inhibiting impulsive decisions. Empirical evidence is provided showing the effects of each component on PG and decision-making across behavioural, neuropsychological, functional neuroimaging and genetic levels. Last, an effect size analysis of the growing pharmacotherapy literature is presented. It is hoped that this model will stimulate multi-level research to solidify our comprehension of biased decision-making in PG and suggest pharmacological and psychological approaches to treatment.
Also flagged:Estrogengene expression17β-estradiolGABA A receptor subunit α6Gabra6glycine receptor α2
Journal Article2011-12-01✓ 1 SnippetPuri J, Bellinger LL, Kramer PR.
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Females report temporomandibular joint (TMJ) pain more than men and studies suggest estrogen modulates this pain response. Our goal in this study was to determine genes that are modulated by physiological levels of 17β-estradiol that could have a role in TMJ pain. To complete this goal, saline or complete Freund's adjuvant was injected in the TMJ when plasma 17β-estradiol was low or when it was at a high proestrus level. TMJ, trigeminal ganglion, and trigeminal subnucleus caudalis/upper cervical cord junction (Vc/C(1-2) ) tissues were isolated from the treated rats and expression of 184 genes was quantitated in each tissue using real-time PCR. Significant changes in the amount of specific transcripts were observed in the TMJ tissues, trigeminal ganglia, and Vc/C(1-2) region when comparing rats with high and low estrogen. GABA A receptor subunit α6 (Gabra6) and the glycine receptor α2 (Glra2) were two genes of interest because of their direct function in neuronal activity and a >29-fold increase in the trigeminal ganglia was observed in proestrus rats with TMJ inflammation. Immunohistochemical studies showed that Gabrα6 and Glrα2 neuronal and not glial expression increased when comparing rats with high and low estrogen. Estrogen receptors α and β are present in neurons of the trigeminal ganglia, whereby 17β-estradiol can alter expression of Gabrα6 and Glrα2. Also, estrogen receptor α (ERα) but not ERβ was observed in satellite glial cells of the trigeminal ganglia. These results demonstrate that genes associated with neurogenic inflammation or neuronal excitability were altered by changes in the concentration of 17β-estradiol.
Also flagged:Propranololgene expressionβ-adrenoceptorcell cycleβ-adrenoceptorscell cycle-related
Journal Article2011-12-01No SnippetsMusumeci M, Maccari S, Sestili P, Signore M, Molinari P, Ambrosio C, Stati T, Colledge WH, Grace AA, Catalano L, Marano G.
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<h4>Background and purpose</h4>Cell cycle regulators are regarded as essential for cardiomyocyte hypertrophic growth. Given that the β-adrenoceptor antagonist propranolol blunts cardiomyocyte hypertrophic growth, we determined whether propranolol alters the expression of cell cycle-related genes in mouse hearts subjected to pressure overload.<h4>Experimental approach</h4>Pressure overload was induced by transverse aortic constriction (TAC), whereas the expression levels of 84 cell cycle-related genes were assayed by real-time PCR. Propranolol (80 mg·kg(-1) ·day(-1) ) was administered in drinking water for 14 days.<h4>Key results</h4>Two weeks after surgery, TAC caused a 46% increase in the left ventricular weight-to-body weight (LVW/BW) ratio but no significant changes in cell cycle gene expression. Propranolol, at plasma concentrations ranging from 10 to 140 ng·mL(-1) , blunted the LVW/BW ratio increase in TAC mice, while significantly increasing expression of 10 cell cycle genes including mitotic cyclins and proliferative markers such as Ki67. This increase in cell cycle gene expression was paralleled by a significant increase in the number of Ki67-positive non-cardiomyocyte cells as revealed by immunohistochemistry and confocal microscopy. β-Adrenoceptor signalling was critical for cell cycle gene expression changes, as genetic deletion of β-adrenoceptors also caused a significant increase in cyclins and Ki67 in pressure overloaded hearts. Finally, we found that metoprolol, a β(1) -adrenoceptor antagonist, failed to enhance cell cycle gene expression in TAC mice.<h4>Conclusions and implications</h4>Propranolol treatment enhances cell cycle-related gene expression in pressure overloaded hearts by increasing the number of cycling non-cardiomyocyte cells. These changes seem to occur via β(2) -adrenoceptor-mediated mechanisms.
Also flagged:Familial colorectal cancer type X syndromehereditary non-polyposis colorectal cancercolorectal cancersfamilial colorectal cancer type XFCCTXtumours
Journal Article2011-12-01✓ 1 SnippetFrancisco I, Albuquerque C, Lage P, Belo H, Vitoriano I, Filipe B, Claro I, Ferreira S, Rodrigues P, Chaves P, Leitão CN, Pereira AD.
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Abstract)
…TP53, SMAD4 andDCC), MGMT and MMR…
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In a fraction of families fulfilling the Amsterdam criteria for hereditary non-polyposis colorectal cancer, colorectal cancers are microsatellite stable and DNA mismatch repair gene (MMR) mutations are not found. These families were designated as familial colorectal cancer type X (FCCTX). We aimed to characterise a group of FCCTX families defined by the Amsterdam criteria and MSS tumours at clinical and molecular level. Twenty-four tumours from 15 FCCTX families were analysed for loss of known tumour suppressor gene (TSG) loci (APC, TP53, SMAD4 and DCC), MGMT and MMR genes promoter methylation, and also APC and KRAS somatic mutations. FCCTX families presented specific clinical features: absence of endometrial tumours, high adenoma/carcinoma ratio (1.91) and prevalence of rectal cancers (13/27, 48%). New molecular features were found: the majority of FCCTX tumours (13/18; 72%) presented TSG loss. TSG loss positive tumours presented frequent APC and KRAS somatic mutations and MGMT methylation [10/13 (77%), 7/13 (54%) and 6/11 (54%), respectively]. In TSG loss negative tumours (5/18; 28%), the same molecular events were found in 2/5 (40%), 2/5 (40%) and 1/3 (33%) tumours, respectively. Transition mutations in KRAS were more frequent among MGMT methylated tumours than in unmethylated [5/8 (63%) vs. 1/10 (10%), P = 0.03]. Although sharing similar clinical features, at least two different molecular entities should exist among FCCTX families, one whose tumours present frequent TSG loss, APC and KRAS somatic mutations, and MGMT promoter methylation, and a second, lesser predominant, with no evidence of TSG loss and rarely presenting promoter methylation.
Also flagged:serotonin transporterposttraumatic stress disorderPTSDbindinganxietydepression
Journal Article2011-12-01✓ 5 SnippetsMurrough JW, Huang Y, Hu J, Henry S, Williams W, Gallezot JD, Bailey CR, Krystal JH, Carson RE, Neumeister A.
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Abstract)
…PTSD would exhibit reduced amygdala 5-HTT expression as measured with positron emission tomography and the recently developed 5-HTT-selective radiotracer [(11)C]AFM…
Abstract)
…the serotonin transporter (5-HTT) may alter stress…
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…Deficient5-HTTfunction and abnormal…
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…has evaluated the5-HTTin humans with…
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…exhibit reduced amygdala5-HTTexpression as measured…
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<h4>Background</h4>The amygdala is a key site where alterations in the regulation of the serotonin transporter (5-HTT) may alter stress response. Deficient 5-HTT function and abnormal amygdala activity have been hypothesized to contribute to the pathophysiology of posttraumatic stress disorder (PTSD), but no study has evaluated the 5-HTT in humans with PTSD. On the basis of translational models, we hypothesized that patients diagnosed with PTSD would exhibit reduced amygdala 5-HTT expression as measured with positron emission tomography and the recently developed 5-HTT-selective radiotracer [(11)C]AFM.<h4>Methods</h4>Fifteen participants with PTSD and 15 healthy control (HC) subjects without trauma history underwent a resting-state positron emission tomography scan.<h4>Results</h4>[(11)C]AFM binding potential (BP(ND)) within the combined bilateral amygdala region of interest was significantly reduced in the PTSD group compared with the HC group (p = .027; 16.3% reduction), which was largely driven by the between-group difference in the left amygdala (p = .008; 20.5% reduction). Furthermore, amygdala [(11)C]AFM BP(ND) was inversely correlated with both Hamilton Rating Scale for Anxiety scores (r = -.55, p = .035) and Montgomery-Åsberg Depression Rating Scale scores (r = -.56, p = .029).<h4>Conclusions</h4>Our findings of abnormally reduced amygdala 5-HTT binding in PTSD and its association with higher anxiety and depression symptoms in PTSD patients support a translational neurobiological model of PTSD directly implicating dysregulated 5-HTT signaling within neural systems underlying threat detection and fear learning.
Also flagged:antithrombin deficiencyInherited(AT) deficiencyvenous thromboembolismAT deficiencydeep vein thrombosis
Journal Article2011-12-01✓ 5 SnippetsJang MJ, Lee JG, Chong SY, Huh JY, Jang MA, Kim HJ, Oh D.
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…A novel splice-site mutation c.42-2A>T (IVS1-2A>T) of SERPINC1 in a Korean family with inherited antithrombin deficiency.…
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…c.42-2A>T (IVS1-2A>T) ofSERPINC1in a Korean…
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…mutation in theSERPINC1gene in a…
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…DNA sequencing ofSERPINC1revealed the novel…
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…splice-site mutation ofSERPINC1in a Korean…
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Inherited antithrombin (AT) deficiency (OMIM 107300) is an autosomal dominant disorder and causes a 20-fold increase in the risk of venous thromboembolism. Herein, we describe a case of a novel splice-site mutation in the SERPINC1 gene in a Korean patient with inherited AT deficiency. The patient was a 35-year-old woman who presented with deep vein thrombosis (DVT) and pulmonary embolism and was without a recent history of any precipitating factors. The obtaining of her family history revealed that her mother had an ischemic stroke and a pulmonary embolism and her two sisters both had an episode of DVT during pregnancy. DNA sequencing of SERPINC1 revealed the novel variant IVS1-2A>T (c.42-2A>T), a substitution in intron 1, in the proband and her daughter. The mutation IVS1-2A>T eliminates the acceptor splice-site of intron 1. The present case is the first novel splice-site mutation of SERPINC1 in a Korean family with inherited AT deficiency.
Also flagged:hepatic nuclear receptoralcoholnuclear receptorchronic hepatitis CHCV infectionnuclear
Journal Article2011-12-01✓ 1 SnippetWu C, Gilroy R, Taylor R, Olyaee M, Abdulkarim B, Forster J, O'Neil M, Damjanov I, Wan YJ.
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…hemochromatosis…
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<h4>Unlabelled</h4>The current study tests a hypothesis that nuclear receptor signaling is altered in chronic hepatitis C patients and that the altered pattern is specific to alcohol drinking history. The expression of a panel of more than 100 genes encoding nuclear receptors, coregulators, and their direct/indirect targets was studied in human livers. Gene expression pattern was compared between 15 normal donor livers and 23 hepatitis C virus (HCV) genotype 1-positive livers from patients without a drinking history (matched for age, sex, and body mass index). HCV infection increased the expression of nuclear receptors small heterodimer partner and constitutive androstane receptor (CAR) as well as genes involved in fatty acid trafficking, bile acid synthesis and uptake, and inflammatory response. However, the expression of retinoid X receptor (RXR) α, peroxisomal proliferator-activated receptor (PPAR) α and β as well as steroid regulatory element-binding protein (SREBP)-1c was decreased in HCV-infected livers. Gene expression pattern was compared in chronic hepatitis C patients with and without a drinking history. Alcohol drinking increased the expression of genes involved in fatty acid uptake, trafficking, and oxidation, but decreased the expression of genes responsible for gluconeogenesis. These changes were consistent with reduced fasting plasma glucose levels and altered expression of upstream regulators that include RXRα, PPARα, and CAR. The messenger RNA levels of fibroblast growth factor 21, interleukin-10, and fatty acid synthase, which are all regulated by nuclear receptors, showed independent correlation with hepatic HCV RNA levels.<h4>Conclusion</h4>Our findings suggest that those genes and pathways that showed altered expression could potentially be therapeutic targets for HCV infection and/or alcohol drinking-induced liver injury.
Also flagged:glucosediabeteshemoglobin AType 2 diabetesmetabolic disorderinsulin
Journal Article2011-12-01✓ 3 SnippetsSoranzo N.
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…AtHFEthe A allele…
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…of the increasedHFEmutation prevalence in…
Discussion)
…hematologic parameters forHFE, TMPRSS6, and…
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Glycated hemoglobin A(1c) (HbA(1c)) indicates the percentage of total hemoglobin that is bound by glucose, produced from the nonenzymatic chemical modification by glucose of hemoglobin molecules carried in erythrocytes. HbA(1c) represents a surrogate marker of average blood glucose concentration over the previous 8 to 12 weeks, or the average lifespan of the erythrocyte, and thus represents a more stable indicator of glycemic status compared with fasting glucose. HbA(1c) levels are genetically determined, with heritability of 47% to 59%. Over the past few years, inroads into understanding genetic predisposition by glycemic and nonglycemic factors have been achieved through genomewide analyses. Here I review current research aimed at discovering genetic determinants of HbA(1c) levels, discussing insights into biologic factors influencing variability in the general and diabetic population, and across different ethnicities. Furthermore, I discuss briefly the relevance of findings for diabetes monitoring and diagnosis.
Rapid advances have been made in the understanding of how the highly proliferative gastrointestinal tract epithelium is regulated under homeostasis and disease. The identification of putative intestinal stem cell (ISC) genes and the ability to culture ISC capable of generating all four lineages plus the architecture of small intestinal (SI) crypts has been transformative. Here, we show that transcription factor Myb governs ISC gene expression, particularly Lgr5. Lgr5 is associated with cells that have the capacity to generate all cell lineages in SI organoid cultures and colorectal cancer cells, which overexpress Myb. Furthermore, Wnt signaling and Myb cooperate in maximal Lgr5 promoter activation while hypomorphic Myb (plt4/plt4) mice have decreased Lgr5 expression. After ionizing radiation (IR), ISC genes are elevated; but in plt4/plt4 mice, this response is substantially subdued. ISC genes bmi-1 and olfm4 are expressed at subnormal levels in plt4/plt4 mice, and bmi-1 is induced with IR to half the level in mutant mice. dcamkl-1 and olfm4 failed to recover after IR in both wild-type (wt) and mutant mice. Although not considered as an ISC gene, cyclinE1 is nevertheless used to assist cells in the emergence from a quiescent state (an expectation of ISC following IR) and is overexpressed after IR in wt mice but does not change from a very low base in plt4/plt4 mice. Self-renewal assays using organoid cultures and inducible Myb knockout studies further highlighted the dependence of ISC on Myb consistent with role in other stem cell-containing tissues.
Also flagged:chronic viral hepatitis Bchronic viral hepatitisliver diseasepolymerasechronic hepatitis Bchronic hepatitis C
Journal Article2011-12-01✓ 5 SnippetsEzzikouri S, Rebbani K, Mostafa A, El Feydi AE, Afifi R, Brahim I, Kitab B, Benazzouz M, Kandil M, Nadifi S, Pineau P, Benjelloun S.
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Title)
…HFE gene on the progression of chronic viral hepatitis B…
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…HFE gene mutations in Moroccan subjects with chronic viral hepatitis B…
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…HFE) gene mutations in chronic viral hepatitis…
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…HFE C282Y allele is very low and H63D mutation carriage occurs in almost 14% of the patients, a rate similar in chronic hepatitis…
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…hemochromatosis (HFE…
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The implication of hemochromatosis (HFE) gene mutations in chronic viral hepatitis remains controversial. The aim of the present study was to measure the frequencies of the common HFE gene mutations in Moroccan subjects with chronic viral hepatitis B and C and to assess their influence on the progression of liver disease. H63D and C282Y mutations were screened by the polymerase chain reaction followed by restriction fragment length polymorphism analysis in 170 chronic hepatitis B patients, 168 chronic hepatitis C patients, and 200 healthy controls. A very small proportion of patients infected with hepatitis B virus (HBV) or hepatitis C virus (HCV; 1.8% and none, respectively) were heterozygous for the C282Y mutation, that is, rates not statistically different from those observed in healthy control (2%, P > 0.05). Similarly, the frequency of the H63D allele was not significantly different between HBV (13.8%) or HCV (14.3%) patients and controls (13.5%, P > 0.05). Multivariate analysis showed that carriers of the H63D mutation infected with HBV are at higher risk to progress towards an advanced liver disease when compared with patients infected with HBV with wild-type (OR = 2.45, 95% CI = 1.07-5.58). In contrast, no association between HFE mutated HCV-infected patients and an increased risk of disease progression was found (OR = 1.24, 95% CI = 0.61-2.50, P = 0.547). In conclusion, in Morocco the frequency of the HFE C282Y allele is very low and H63D mutation carriage occurs in almost 14% of the patients, a rate similar in chronic hepatitis patients and healthy controls. In the case of chronic hepatitis B, the carriage of the H63D variant represents a risk factor of evolution towards a more active disease.
Polyunsaturated fatty acids (PUFA) play important roles in the normal physiology and in pathological states including inflammation and cancer. While much is known about the biosynthesis and biological activities of eicosanoids derived from ω6 PUFA, our understanding of the corresponding ω3 series lipid mediators is still rudimentary. The purpose of this review is not to offer a comprehensive summary of the literature on fatty acids in prostate cancer but rather to highlight some of the areas where key questions remain to be addressed. These include substrate preference and polymorphic variants of enzymes involved in the metabolism of PUFA, the relationship between de novo lipid synthesis and dietary lipid metabolism pathways, the contribution of cyclooxygenases and lipoxygenases as well as terminal synthases and prostanoid receptors in prostate cancer, and the potential role of PUFA in angiogenesis and cell surface receptor signaling.
Also flagged:serotonin transporterdepressiongestation-abuse5-HTTLPR
Journal Article2011-12-01✓ 1 SnippetScheid JM, Holzman CB, Jones N, Friderici KH, Jernigan KA, Symonds LL, Sikorskii A, Fisher R.
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<h4>Objective</h4>In earlier analyses of nonHispanic White women we found a stronger relation between abuse history and midpregnancy elevated depressive symptoms in women with the serotonin transporter (5-HTTLPR) S/S genotype. Here, we focus on African-American women (N=698). Our inquiry is motivated by racial differences in depression diagnosis/treatment, stressors, and frequency of major 5-HTTLPR alleles (S, LA, LG).<h4>Materials and methods</h4>Stressful life events (lifetime) and depressive symptoms (current) were ascertained at 15-27 weeks gestation. A Center for Epidemiological Studies Depression Score of more than or equal to 18 was considered 'elevated'. Life events were scored together and separated into six subconstructs. 5-HTTLPR genotypes were grouped as follows: (i) L and S alleles, (ii) S-LG equivalence ('triallelic to biallelic'), and (iii) LA/LA, all others, S/S ('high/intermediate/low'). Odds ratios (OR) for 'elevated' depressive symptoms-life events (total and subconstructs) relations were calculated for each genotype grouping.<h4>Results</h4>The prevalence of 'elevated' depressive symptoms did not vary by genotype. The relation between stressful life events and 'elevated' depressive symptoms was stronger in S/S compared with LA/LA genotype (interaction P=0.11). Of the six subconstructs, only abuse showed a statistically significant gene-environment interaction. The OR for the abuse-'elevated' depressive symptoms association was greater for S/S vs. LA/LA genotype (interaction P=0.03) and in the 'triallelic to biallelic' grouping (interaction P=0.04). In the 'high/intermediate/low' grouping, 'low' (S/S) had a higher OR (5.5) than both 'intermediate' and 'high' (ORs≤2.3) (interaction P=0.10).<h4>Conclusions</h4>These results show the importance of examining racial groups, specific stressful events, and different 5-HTTLPR genotype groupings when exploring gene-environment interactions in depression.
Thromboxane A(2) (TXA(2)) is a biologically active metabolite of arachidonic acid formed by the action of the terminal synthase, thromboxane A(2) synthase (TXA(2)S), on prostaglandin endoperoxide (PGH(2)). TXA(2) is responsible for multiple biological processes through its cell surface receptor, the T-prostanoid (TP) receptor. Thromboxane A(2) synthase and TP are the two necessary components for the functioning of this potent bioactive lipid. Thromboxane A(2) is widely implicated in a range of cardiovascular diseases, owing to its acute and chronic effects in promoting platelet aggregation, vasoconstriction, and proliferation. In recent years, additional functional roles for both TXA(2)S and TP in cancer progression have been indicated. Increased cyclooxygenase (COX)-2 expression has been described in a variety of human cancers, which has focused attention on TXA(2) as a downstream metabolite of the COX-2-derived PGH(2). Several studies suggest potential involvement of TXA(2)S and TP in tumor progression, especially tumor cell proliferation, migration, and invasion that are key steps in cancer progression. In addition, the regulation of neovascularization by TP has been identified as a potent source of control during oncogenesis. There have been several recent reviews of TXA(2)S and TP but thus far none have discussed its role in cancer progression and metastasis in depth. This review will focus on some of the more recent findings and advances with a significant emphasis on understanding the functional role of TXA(2)S and TP in cancer progression and metastasis.
Also flagged:peptidesIronhereditary hemochromatosisiron-loadinganemiasβ-thalassemia
Journal Article2011-12-01✓ 3 SnippetsPreza GC, Ruchala P, Pinon R, Ramos E, Qiao B, Peralta MA, Sharma S, Waring A, Ganz T, Nemeth E.
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Iron overload is the hallmark of hereditary hemochromatosis and a complication of iron-loading anemias such as β-thalassemia. Treatment can be burdensome and have significant side effects, and new therapeutic options are needed. Iron overload in hereditary hemochromatosis and β-thalassemia intermedia is caused by hepcidin deficiency. Although transgenic hepcidin replacement in mouse models of these diseases prevents iron overload or decreases its potential toxicity, natural hepcidin is prohibitively expensive for human application and has unfavorable pharmacologic properties. Here, we report the rational design of hepcidin agonists based on the mutagenesis of hepcidin and the hepcidin-binding region of ferroportin and computer modeling of their docking. We identified specific hydrophobic/aromatic residues required for hepcidin-ferroportin binding and obtained evidence in vitro that a thiol-disulfide interaction between ferroportin C326 and the hepcidin disulfide cage may stabilize binding. Guided by this model, we showed that 7–9 N-terminal amino acids of hepcidin, including a single thiol cysteine, comprised the minimal structure that retained hepcidin activity, as shown by the induction of ferroportin degradation in reporter cells. Further modifications to increase resistance to proteolysis and oral bioavailability yielded minihepcidins that, after parenteral or oral administration to mice, lowered serum iron levels comparably to those after parenteral native hepcidin. Moreover, liver iron concentrations were lower in mice chronically treated with minihepcidins than those in mice treated with solvent alone. Minihepcidins may be useful for the treatment of iron overload disorders.
Also flagged:nomegestrolacetateoestradiollevonorgestrelethinylestradiolhaemostasis
Journal Article2011-12-01✓ 4 SnippetsÅgren UM, Anttila M, Mäenpää-Liukko K, Rantala ML, Rautiainen H, Sommer WF, Mommers E.
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…of antithrombin III (ATIII) was measured by…
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…colorimetric STA STAchromATIIIassay using bovine…
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…1+2, D-dimer andATIII.…
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…the anticoagulatory factorsATIII, protein C, and…
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<h4>Objectives</h4>To compare the effects of a combined oral contraceptive (COC) containing nomegestrol acetate and 17β-oestradiol (NOMAC/E2) on haemostasis, lipids, carbohydrate metabolism, C-reactive protein (CRP) and sex hormone-binding globulin (SHBG) with those of a COC containing levonorgestrel and ethinylestradiol (LNG/EE).<h4>Methods</h4>In a randomised, open-label study, 121 healthy women, 18-50 years of age, were randomly assigned to receive NOMAC/E2 (2.5 mg/1.5 mg) in a 24/4-day regimen (n=60) or LNG/EE (150 μg/30 μg) in a 21/7-day regimen (n=61) for six cycles. The primary outcome was the change from baseline to cycle 6 for all indices.<h4>Results</h4>All parameters were similar at baseline between the two groups. Over six cycles, NOMAC/E2 had less effect on most haemostatic indices than LNG/EE. Lipids were essentially unchanged with NOMAC/E2, whereas with LNG/EE high-density lipoprotein cholesterol decreased and low-density lipoprotein cholesterol and triglycerides slightly increased. NOMAC/E2 induced negligible changes in glucose and insulin parameters, in contrast to LNG/EE. A much smaller increase in CRP was observed with NOMAC/E2 than with LNG/EE. NOMAC/E2 was associated with a greater increase in SHBG.<h4>Conclusions</h4>The monophasic COC NOMAC/E2 had less influence on haemostasis, lipids and carbohydrate metabolism than the COC LNG/EE.
Journal Article2011-12-01No SnippetsLandau DA, Slack FJ.
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MicroRNAs (miRNAs) are aiding our understanding of cancer biology, and are now coming close to therapeutic use as well. Here, we focus specifically on the interaction between miRNAs and genomic instability. MiRNA regulation is essential to many cellular processes, and escape from this regulatory network seems to be a common characteristic of malignant transformation. Genomic instability may preferentially target miRNAs either because of selective pressure or because of inherent vulnerability related to their location near fragile sites. Furthermore, disruption of miRNA processing elements affords a more global release from miRNA regulation. Finally, we review how miRNAs function as both effectors and modulators of the DNA damage response, intricately weaved with traditional elements such as ATM, P53, and MMR. Thus, miRNAs are important substrates for genomic instability and play a crucial role in cellular DNA sensing and repair mechanisms.
Also flagged:alkyneporphyrincarbazoleethynylenefullerenestoluene
Journal Article2011-12-01No SnippetsZhang C, Wang Q, Long H, Zhang W.
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Dynamic covalent chemistry (DCC) provides an intriguing and highly efficient approach for building molecules that are usually thermodynamically favored. However, the DCC methods that are efficient enough to construct large, complex molecules, particularly those with three-dimensional (3-D) architectures, are still very limited. Here, for the first time, we have successfully utilized alkyne metathesis, a highly efficient DCC approach, to construct the novel 3-D rectangular prismatic molecular cage COP-5 in one step from a readily accessible porphyrin-based precursor. COP-5 consists of rigid, aromatic porphyrin and carbazole moieties as well as linear ethynylene linkers, rendering its shape-persistent nature. Interestingly, COP-5 serves as an excellent receptor for fullerenes. It forms 1:1 complexes with C(60) and C(70) with association constants of 1.4 × 10(5) M(-1) (C(60)) and 1.5 × 10(8) M(-1) (C(70)) in toluene. This represents one of the highest binding affinities reported so far for purely organic fullerene receptors. COP-5 shows an unprecedented high selectivity in binding C(70) over C(60) (K(C70)/K(C60) > 1000). Moreover, the binding between the cage and fullerene is fully reversible under the acid-base stimuli, thus allowing successful separation of C(70) from a C(60)-enriched fullerene mixture (C(60)/C(70), 10/1 mol/mol) through the "selective complexation-decomplexation" strategy.
Also flagged:IronHereditary hemochromatosis type 1ashereditary hemochromatosis classicaliron overload disorder
Journal Article2011-12-01✓ 4 SnippetsHulihan MM, Sayers CA, Grosse SD, Garrison C, Grant AM.
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Abstract)
…Hereditary hemochromatosis type 1, also known as hereditary hemochromatosis classical (HHC), is an iron overload disorder associated, in most cases, with mutations of the hemochromatosis (HFE) gene.…
Hereditary hemochromatosis type 1, also known as hereditary hemochromatosis classical (HHC), is an iron overload disorder associated, in most cases, with mutations of the hemochromatosis (HFE) gene. Although suggested algorithms for diagnosing iron overload are available, there are still questions about options for genetic and biochemical screening for hemochromatosis and duration of treatment. This article provides a summary of an expert workgroup meeting convened on September 24-25, 2009, entitled "Iron Overload: What is the Role of Public Health?" The purpose of the meeting was to enable subject matter experts to share their most recent clinical and scientific iron overload information and to facilitate the discussion of future endeavors, with special emphasis on the role of public health in this field. The two main topics were the research priorities of the field, including clinical, genetic, and public health issues, and the concerns about the validity of current screening recommendations for the condition.
Also flagged:nicotine dependencenicotinemetabolismdopamineCYP2A6nicotine receptor
Journal Article2011-12-01No SnippetsSchnoll RA, Leone FT.
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The application of genomic medicine to the treatment of nicotine dependence holds great promise for revitalizing the steady decline in smoking rates witnessed in the USA over the past several decades. This paper examines the current knowledge base concerning the use of biomarkers to guide the selection of nicotine dependence treatments. First, we review the neurobiology of nicotine dependence and present evidence that supports its heritability. We then discuss the various studies of pharmacokinetic and pharmacodynamic genes related to therapeutic response. Current evidence suggests that biomarkers of genetic variability in both nicotine metabolism, referred to as the nicotine metabolite ratio, and dopamine genotypes may be useful for guiding treatment selection for nicotine dependence. Barriers to the translation of this research to clinical practice are discussed, as are directions for future research.
Also flagged:pathogenesisdiabetespeptidesglucosetype 2 diabetesimpaired
Journal Article2011-12-01✓ 1 SnippetMcKillop AM, Flatt PR.
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…indicative of clinicalhemochromatosis) and development of…
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Clinical and epidemiological metabolomics provides a unique opportunity to look at genotype-phenotype relationships as well as the body\x{2019}s responses to environmental and lifestyle factors. Fundamentally, it provides information on the universal outcome of influencing factors on disease states and has great potential in the early diagnosis, therapy monitoring, and understanding of the pathogenesis of disease. Diseases, such as diabetes, with a complex set of interactions between genetic and environmental factors, produce changes in the body\x{2019}s biochemical profile, thereby providing potential markers for diagnosis and initiation of therapies. There is clearly a need to discover new ways to aid diagnosis and assessment of glycemic status to help reduce diabetes complications and improve the quality of life. Many factors, including peptides, proteins, metabolites, nucleic acids, and polymorphisms, have been proposed as putative biomarkers for diabetes. Metabolomics is an approach used to identify and assess metabolic characteristics, changes, and phenotypes in response to influencing factors, such as environment, diet, lifestyle, and pathophysiological states. The specificity and sensitivity using metabolomics to identify biomarkers of disease have become increasingly feasible because of advances in analytical and information technologies. Likewise, the emergence of high-throughput genotyping technologies and genome-wide association studies has prompted the search for genetic markers of diabetes predisposition or susceptibility. In this review, we consider the application of key metabolomic and genomic methodologies in diabetes and summarize the established, new, and emerging metabolomic and genomic biomarkers for the disease. We conclude by summarizing future insights into the search for improved biomarkers for diabetes research and human diagnostics.
Infantile spasms constitute an age-dependent epilepsy, highly associated with cognitive impairment, autism, and movement disorders. Previous classification systems focused on a distinction between symptomatic and cryptogenic etiologies, and have not kept pace with recent discoveries of mutations in genes in key pathways of central nervous system development in patients with infantile spasms. Children with certain genetic syndromes are much likelier to manifest infantile spasms, and we review the literature to propose a genetic classification of these disorders. Children demonstrating genetic associations with infantile spasms also manifest phenotypes beyond epilepsy that may be explained by recent advances in the understanding of underlying biological mechanisms. Therefore we propose a biologic classification of genes highly associated with infantile spasms, and articulate models for infantile spasms pathogenesis based on those data. The two best described pathways of pathogenesis involve abnormalities in the gene regulatory network of gamma-aminobutyric acidergic forebrain development and abnormalities in molecules expressed at the synapse. These genetic and biologic classifications are flexible, and they should encourage much needed progress in syndrome recognition, clinical genetic testing, and the development of new therapies targeting specific pathways of pathogenesis.
Also flagged:ironuric acidpathogenesischronic venous insufficiencymalonyldialdehydelumen
Journal Article2011-12-01✓ 2 SnippetsBudzyń M, Iskra M, Krasiński Z, Dzieciuchowicz Ł, Kasprzak M, Gryszczyńska B.
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…mutation of theHFEgene encoding the…
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…conditions, such ashemochromatosis, diabetes and cardiovascular…
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<h4>Background</h4>The aim of this study was to evaluate serum iron concentration and influence of this element on biomarkers of oxidative stress in patients affected by chronic venous insufficiency (CVI).<h4>Material/methods</h4>Serum iron (SI) concentration and plasma parameters of oxidant-antioxidant balance (i.e., malonyldialdehyde [MDA], uric acid [UA] concentration, and total antioxidant capacity [TAC]) were compared between 35 patients divided into appropriate groups and 23 healthy individuals.<h4>Results</h4>The subgroups analysis showed that SI concentration was significantly higher only in patients with shorter duration of CVI in comparison with the control group (P = 0.013). Significant, negative correlation was found between SI concentration and duration of the disease (r = -0.422, P = 0.014), age of the patients (r = -0.542, P = 0.001) and BMI (r = -0.408, P = 0.018). Mean value of MDA concentration and TAC capacity were higher in patients with CVI in comparison with healthy individuals (P < 0.05). UA concentration was decreased, especially in CVI patients with mild clinical stage of disease and shorter CVI duration (P = 0.047; P = 0.034). There was no significant correlation found between SI concentration and the parameters of oxidant-antioxidant balance.<h4>Conclusions</h4>High concentration of MDA and low UA level in blood of CVI patients suggests that oxidative stress plays an important role in the pathogenesis of the disease. The increase in SI concentration observed in the early stage of CVI can enhance free radicals formation; however, direct evidence has not been provided by the present study.
Also flagged:infertilemale infertilityinseminationvaricocelectomyinfertilitymale-factor infertility
Journal Article2011-12-01No SnippetsTrussell JC, Christman GM, Ohl DA, Legro RS, Krawetz SA, Snyder PJ, Patrizio P, Polotsky AJ, Diamond MP, Casson PR, Coutifaris C, Barnhart K, Brzyski RG, Schlaff WD, Meacham R, Shin D, Thomas T, Zhang M, Santoro N, Eisenberg E, Zhang H, Reproductive Medicine Network.
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<h4>Objective</h4>To review reasons for suboptimal recruitment for a randomized controlled trial (RCT) of varicocelectomy versus intrauterine insemination (IUI) for treatment of male infertility and to suggest means for improving future study recruitment.<h4>Design</h4>Survey of Reproductive Medicine Network (RMN) participating sites.<h4>Setting</h4>Reproductive Medicine Network.<h4>Patient(s)</h4>None.<h4>Intervention(s)</h4>None.<h4>Main outcome measure(s)</h4>Ascertain reasons for inadequate recruitment and suggest improvements for future varicocelectomy trails.<h4>Result(s)</h4>This study screened seven and enrolled three couples, with the first couple randomized on June 30, 2010. The study was subsequently stopped on March 30, 2011. The following themes were cited most frequently by sites and therefore determined to be most likely to have played a role in suboptimal recruitment: [1] men must be screened at the beginning of a couple's infertility evaluation, [2] inclusion of infertile women who had failed previous fertility interventions appeared to be associated with the couple's intolerance of a placebo arm, and [3] an apparent bias against the use of unstimulated IUI cycles indicated a prejudicial preference for surgical intervention in the male partner.<h4>Conclusion(s)</h4>Improved recruitment may be realized through screening infertile men as early as possible while minimizing study-related time commitments. Focused patient education may promote improved equipoise and acceptance of a placebo arm in male infertility studies. Creative approaches to implementing varicocelectomy trials must be considered in addition to having a network of motivated researchers who carry a high volume of possible study participants because very large numbers may need to be screened to complete the clinical trial enrollment.
Also flagged:soft tissue infectionsbacteremiasepsispathogenesisironcoagulation
Journal Article2011-12-01✓ 1 SnippetDeDent A, Kim HK, Missiakas D, Schneewind O.
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Staphylococcus aureus is a commensal of the human skin or nares and a pathogen that frequently causes skin and soft tissue infections as well as bacteremia and sepsis. Recent efforts in understanding the molecular mechanisms of pathogenesis revealed key virulence strategies of S. aureus in host tissues: bacterial scavenging of iron, induction of coagulation pathways to promote staphylococcal agglutination in the vasculature, and suppression of innate and adaptive immune responses. Advances in all three areas have been explored for opportunities in vaccine design in an effort to identify the critical protective antigens of S. aureus. Human clinical trials with specific subunit vaccines have failed, yet provide important insights for the design of future trials that must address the current epidemic of S. aureus infections with drug-resistant isolates (MRSA, methicillin-resistant S. aureus).
Also flagged:ironmetabolismHepcidincreatininealbumintransferrin receptor
Journal Article2011-12-01✓ 1 SnippetMalyszko J, Malyszko JS, Levin-Iaina N, Koc-Zorawska E, Kozminski P, Mysliwiec M.
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…trigger diabetes inHFEpatient [ 17…
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<h4>Introduction</h4>Hemojuvelin (HJV) is highly expressed in the liver, skeletal muscles, and heart, seems to play a role in iron absorption and release from cells, and has anti-inflammatory properties. Moreover, HJV plays an essential role in the regulation of hepcidin expression, specifically in the iron-sensing pathway. Hepcidin has emerged as a key regulator of iron homeostasis. In this study we tested for the first time the hypothesis that HJV is related to iron metabolism in hemodialysis (HD) patients.<h4>Methods</h4>Iron status, complete blood count, and serum creatinine, albumin, and lipids were assessed, using standard laboratory methods. Serum levels of soluble transferrin receptor (sTFR), high-sensitivity CRP, IL-6, hepcidin, and HJV were measured using commercially available kits.<h4>Results</h4>Serum HJV, hepcidin, ferritin, IL-6, hsCRP, and serum creatinine were significantly higher (all P<0.001), whereas serum iron, sTFR, transferrin, hemoglobin, and erythrocyte count were significantly lower in HD patients, compared to healthy volunteers (all P<0.001). In univariate analysis, HJV was strongly correlated (P<0.001) with ferritin, transferrin saturation, and TIBC, as well as with hsCRP, hepcidin, Kt/V (P<0.01) and residual renal function, the presence of diabetes, APKD, and coronary heart disease. Predictors of HJV level in multiple regression analysis were ferritin (beta value was 0.50, P=0.00004) and transferrin saturation (beta value was 0.47, P=0.0002), explaining 81% of the HJV variations.<h4>Conclusions</h4>Serum HJV is elevated in HD patients and related predominantly to kidney function and iron metabolism. However, HJV is probably not correlated to inflammation. HJV appears to be a new player in iron metabolism in these patients.
Also flagged:noncardioembolic strokeCSMD1DDR1NEU3UMODL1NCR3
Journal Article2011-12-01✓ 1 SnippetLuke MM, Berger K, Rowland CM, Catanese JJ, Tong CH, Ross DA, Garcia V, Kuhlenbaeumer G, Ringelstein EB, Pullinger CR, Malloy MJ, Deedwania P, Ellis SG, Kane JP, Devlin JJ, Lalouschek W, Mannhalter C.
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Abstract)
…Study: rs362277 inHTT(OR 1.39, 90%…
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<h4>Background</h4>Gene variants associated with disease could reveal novel mechanisms. We searched for single nucleotide polymorphisms (SNPs) associated with noncardioembolic stroke (nonCES).<h4>Methods</h4>We tested 24,926 SNPs in or near genes for association with nonCES in the Vienna Study (551 cases, 815 controls) and then evaluated the associated SNPs in the UCSF-CC Study (570 cases, 1,604 controls) first in pooled DNA samples and then in individual DNA samples. We then asked whether the risk alleles of the SNPs associated with increased risk in both studies were also associated with increased risk of nonCES in the German Study (728 cases, 1,041 controls).<h4>Results</h4>Six of the 46 SNPs that were associated with nonCES in both the Vienna and the UCSF-CC Studies were also associated with nonCES in the German Study: rs362277 in HTT (OR 1.39, 90% CI 1.12-1.71), rs2924914 near CSMD1 (OR 1.22, 90% CI 1.04-1.43), rs1264352 near DDR1 (OR 1.20, 90% CI 1.02-1.41), rs544115 in NEU3 (OR 1.63, 90% CI 1.02-2.62), rs12481805 in UMODL1 (OR 1.31, 90% CI 1.01-1.81), and rs2857595 near NCR3 (OR 1.15, 90% CI 1.00-1.32). Accounting for multiple testing of 46 SNPs, these 6 SNPs had a false discovery rate of 0.69.<h4>Conclusions</h4>Some of the 6 SNPs may be associated with nonCES but most may be false positives. These 6 SNPs merit investigation in additional nonCES study populations.
Preferential accumulation of mutant proteins in the nucleus has been suggested to be the molecular culprit that confers cellular toxicity in the neurodegenerative disorders caused by polyglutamine (polyQ) expansion. Here, we use dynamic imaging approaches, orthogonal cross-seeding, and composition analysis to examine the dynamics and structure of nuclear and cytoplasmic inclusions of atrophin-1, implicated in dentatorubropallidoluysian atrophy, a polyQ-based disease with complex clinical features. Our results reveal a large heterogeneity in the dynamics of the nuclear inclusions compared with the compact and immobile cytoplasmic aggregates. At least two types of inclusions of expanded atrophin-1 with different mobility of the molecular species and ability to exchange with the surrounding monomer pool coexist in the nucleus. Intriguingly, the enrichment of nuclear inclusions with slow dynamics parallels changes in the aggregate core architecture that are dominated by the polyQ stretch. We propose that the observed complexity in the dynamics of the nuclear inclusions provides a molecular explanation for the enhanced cellular toxicity of the nuclear aggregates in polyQ-based neurodegeneration.
Borderline personality disorder (BPD) is a complex psychiatric disease of increasing importance. Epigenetic alterations are hallmarks for altered gene expression and could be involved in the etiology of BPD. In our study we analyzed DNA methylation patterns of 14 neuropsychiatric genes (COMT, DAT1, GABRA1, GNB3, GRIN2B, HTR1B, HTR2A, 5-HTT, MAOA, MAOB, NOS1, NR3C1, TPH1 and TH). DNA methylation was analyzed by bisulfite restriction analysis and pyrosequencing in whole blood samples of patients diagnosed with DSM-IV BPD and in controls. Aberrant methylation was not detectable using bisulfite restriction analysis, but a significantly increased methylation of HTR2A, NR3C1, MAOA, MAOB and soluble COMT (S-COMT) was revealed for BPD patients using pyrosequencing. For HTR2A the average methylation of four CpG sites was 0.8% higher in BPD patients compared to controls (p = 0.002). The average methylation of NR3C1 was 1.8% increased in BPD patients compared to controls (p = 0.0003) and was higher at 2 out of 8 CpGs (p ≤ 0.04). In females, an increased average methylation (1.5%) of MAOA was observed in BPD patients compared to controls (p = 0.046). A similar trend (1.4% higher methylation) was observed for MAOB in female BPD patients and increased methylation was significant for 1 out of 6 CpG sites. For S-COMT, a higher methylation of 2 out of 4 CpG sites was revealed in BPD patients (p ≤ 0.02). In summary, methylation signatures of several promoter regions were established and a significant increased average methylation (1.7%) occurred in blood samples of BPD patients (p < 0.0001). Our data suggest that aberrant epigenetic regulation of neuropsychiatric genes may contribute to the pathogenesis of BPD.
Also flagged:SREBPironergosterolSterol regulatory element binding proteinstranscription factorstriazole
Journal Article2011-12-01No SnippetsBlatzer M, Barker BM, Willger SD, Beckmann N, Blosser SJ, Cornish EJ, Mazurie A, Grahl N, Haas H, Cramer RA.
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Sterol regulatory element binding proteins (SREBPs) are a class of basic helix-loop-helix transcription factors that regulate diverse cellular responses in eukaryotes. Adding to the recognized importance of SREBPs in human health, SREBPs in the human fungal pathogens Cryptococcus neoformans and Aspergillus fumigatus are required for fungal virulence and susceptibility to triazole antifungal drugs. To date, the exact mechanism(s) behind the role of SREBP in these observed phenotypes is not clear. Here, we report that A. fumigatus SREBP, SrbA, mediates regulation of iron acquisition in response to hypoxia and low iron conditions. To further define SrbA's role in iron acquisition in relation to previously studied fungal regulators of iron metabolism, SreA and HapX, a series of mutants were generated in the ΔsrbA background. These data suggest that SrbA is activated independently of SreA and HapX in response to iron limitation, but that HapX mRNA induction is partially dependent on SrbA. Intriguingly, exogenous addition of high iron or genetic deletion of sreA in the ΔsrbA background was able to partially rescue the hypoxia growth, triazole drug susceptibility, and decrease in ergosterol content phenotypes of ΔsrbA. Thus, we conclude that the fungal SREBP, SrbA, is critical for coordinating genes involved in iron acquisition and ergosterol biosynthesis under hypoxia and low iron conditions found at sites of human fungal infections. These results support a role for SREBP-mediated iron regulation in fungal virulence, and they lay a foundation for further exploration of SREBP's role in iron homeostasis in other eukaryotes.
Homeostasis of most adult tissues is maintained by balancing stem cell self-renewal and differentiation, but whether post-transcriptional mechanisms can regulate this process is unknown. Here, we identify that an RNA methyltransferase (Misu/Nsun2) is required to balance stem cell self-renewal and differentiation in skin. In the epidermis, this methyltransferase is found in a defined sub-population of hair follicle stem cells poised to undergo lineage commitment, and its depletion results in enhanced quiescence and aberrant stem cell differentiation. Our results reveal that post-transcriptional RNA methylation can play a previously unappreciated role in controlling stem cell fate.
Also flagged:heme oxygenase-1lipopolysaccharidegingivitisHO-1Gomisins Gpro-inflammatory cytokines
Journal Article2011-12-01No SnippetsRyu EY, Park SY, Kim SG, Park DJ, Kang JS, Kim YH, Seetharaman R, Choi YW, Lee SJ.
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Periodontitis, a chronic inflammatory periodontal disease that develops from gingivitis, is caused by periodontal pathogenic bacteria such as Porphyromonas gingivalis. Recent studies have focused on the antioxidant, anti-human immunodeficiency virus, anticarcinogenic, and anti-inflammatory properties of gomisins. However, the anti-inflammatory activities of gomisin plants through heme oxygenase-1 (HO-1) signals remain poorly defined. We found that gomisins' anti-inflammatory activity occurs via the induction of HO-1 expression. Gomisins G and J inhibit the production of the pro-inflammatory cytokines tumor necrosis factor-α, interleukin-1β, and interleukin-6 and also block nuclear factor-κB activation in Raw264.7 cells stimulated with P. gingivalis lipopolysaccharide. Furthermore, pro-inflammatory cytokine production is inhibited through the induction of HO-1 expression. HO-1 expression is induced by all gomisins, but their anti-inflammatory activity via HO-1 signaling is observed with gomisins G and J, and not A. We found that gomisins G and J extracted from Schisandria chinensis can inhibit the P. gingivalis lipopolysaccharide induced-inflammatory responses in Raw264.7 cells.
Also flagged:Huntington's choreachoreacognitive declineHuntington's diseaseHDadult-onset neurodegenerative disorder
Journal Article2011-12-01✓ 1 SnippetKlein C.
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…repeat in theHTTgene in the…
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Wilson's Queen Square Case 9 with Huntington's chorea shows a 68-year-old man with mild to moderate generalized chorea, impaired fixation, and probable cognitive decline in keeping with a diagnosis of Huntington's disease (HD). An age of onset in the late sixties and a negative family history suggest a relatively small expanded trinucleotide repeat in the HTT gene in the patient and reduced penetrance of an even shorter repeat allele in one of his parents. A highly sensitive and specific gene test has been offered worldwide for diagnostic testing of HD for almost two decades. This test, obviously unavailable at Wilson's times, became the historic frontrunner for guidelines of symptomatic, presymptomatic, and prenatal testing for an adult-onset neurodegenerative disorder. Regarding treatment of HD, however, we are still awaiting the successful translation of research results into the development of effective cause-directed, neuropreventive and neurorestaurative therapies.
Also flagged:gene expressiontotranscription factorsCREBSRFEGR1
Journal Article2011-12-01No SnippetsBenito E, Valor LM, Jimenez-Minchan M, Huber W, Barco A.
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Long-lasting forms of neuronal plasticity require de novo gene expression, but relatively little is known about the events that occur genome-wide in response to activity in a neuronal network. Here, we unveil the gene expression programs initiated in mouse hippocampal neurons in response to different stimuli and explore the contribution of four prominent plasticity-related transcription factors (CREB, SRF, EGR1, and FOS) to these programs. Our study provides a comprehensive view of the intricate genetic networks and interactions elicited by neuronal stimulation identifying hundreds of novel downstream targets, including novel stimulus-associated miRNAs and candidate genes that may be differentially regulated at the exon/promoter level. Our analyses indicate that these four transcription factors impinge on similar biological processes through primarily non-overlapping gene-expression programs. Meta-analysis of the datasets generated in our study and comparison with publicly available transcriptomics data revealed the individual and collective contribution of these transcription factors to different activity-driven genetic programs. In addition, both gain- and loss-of-function experiments support a pivotal role for CREB in membrane-to-nucleus signal transduction in neurons. Our data provide a novel resource for researchers wanting to explore the genetic pathways associated with activity-regulated neuronal functions.
Also flagged:chaperoneAutophagyHuntington's diseaseHDneurodegenerative disorderautophagic vacuoles
Journal Article2011-12-01✓ 1 SnippetKoga H, Martinez-Vicente M, Arias E, Kaushik S, Sulzer D, Cuervo AM.
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Autophagy contributes to the removal of prone-to-aggregate proteins, but in several instances these pathogenic proteins have been shown to interfere with autophagic activity. In the case of Huntington's disease (HD), a congenital neurodegenerative disorder resulting from mutation in the huntingtin protein, we have previously described that the mutant protein interferes with the ability of autophagic vacuoles to recognize cytosolic cargo. Growing evidence supports the existence of cross talk among autophagic pathways, suggesting the possibility of functional compensation when one of them is compromised. In this study, we have identified a compensatory upregulation of chaperone-mediated autophagy (CMA) in different cellular and mouse models of HD. Components of CMA, namely the lysosome-associated membrane protein type 2A (LAMP-2A) and lysosomal-hsc70, are markedly increased in HD models. The increase in LAMP-2A is achieved through both an increase in the stability of this protein at the lysosomal membrane and transcriptional upregulation of this splice variant of the lamp-2 gene. We propose that CMA activity increases in response to macroautophagic dysfunction in the early stages of HD, but that the efficiency of this compensatory mechanism may decrease with age and so contribute to cellular failure and the onset of pathological manifestations.
Also flagged:Lamivudinechronicchronic hepatitis Bhepatitis B surface antigenpolymerasetyrosine
Journal Article2011-12-01✓ 1 SnippetYıldız O, Aygen B, Demirtürk N, Demirdal T, Inan D, Yıldırmak T, Kantürk A, Tütüncü E, Hepatitis B Study Group.
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…hemochromatosis…
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<h4>Aim</h4>To determine the distribution of viral genotypes for primary or acquired lamivudine resistance.<h4>Methods</h4>A total of 283 patients with chronic hepatitis B virus (HBV) infection (245 patients with chronic hepatitis B and 38 inactive hepatitis B surface antigen carriers) were included in the study. The HBV genotype was determined by using quantitative real-time polymerase chain reaction and sequence analysis, and tyrosine-methionine-aspartate-aspartate (YMDD) motif mutations were determined using the reverse transcriptase hybridization method.<h4>Results</h4>Lamivudine resistance was determined in a total of 25 (10.7%) chronic hepatitis B patients. Eight subjects (4%) had primary resistance to lamivudine, and 17 (53.1%) had secondary resistance to lamivudine. Genotype D, which was isolated from 267 of the patients with chronic HBV infection, was the dominant genotype in Turkey.<h4>Conclusion</h4>Identification of YMDD motif mutations should have a positive impact on the selection of proper antiviral medication for patients, even for those who are nucleoside naïve.
Also flagged:hepatocellular carcinomasorafenibmultikinasealpha-fetoproteinalbuminLiver Cancer
Journal Article2011-12-01✓ 1 SnippetSundaralingam T, Gill S.
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…hemochromatosis…
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<h4>Background</h4>Systemic treatment options in hepatocellular carcinoma (hcc) are limited. Sorafenib, a multikinase inhibitor, has been shown to improve survival in patients with advanced hcc and adequate hepatic reserve. Currently, the proportion of referred patients with hcc that would be eligible for sorafenib therapy is unclear. We reviewed patterns in the presentation and management of referred patients with hcc at the BC Cancer Agency (bcca) before the availability of sorafenib.<h4>Methods</h4>Records of patients with hcc referred to the bcca from January 1, 2003, to December 31, 2007, were reviewed. Distributions were analyzed using frequency statistics.<h4>Results</h4>Of 518 patients reviewed, 77% were men and 45% were of Asian ethnicity; median age was 64 years. Histology confirmation was available in only 34% of the patients; 64% had an elevated level of alpha-fetoprotein at diagnosis. The Child-Pugh score at presentation could not be determined in 56%; the most common missing variable was albumin (44%). Among the 226 evaluable patients, the Child-Pugh classification was A in 140 (62%), B in 64 (28%), and C in 22 (10%). Eastern Cooperative Oncology Group performance status was not documented in 40% of patients. The TNM staging was recorded per agency protocol; however, it was incompletely documented in most patients. Distant metastases were recorded in 12% of patients, and 75 patients (15%) underwent hepatic resection before referral. After bcca referral, no further therapy was offered to 287 patients (54%), regional therapy was offered to 170 (33%), and chemotherapy was offered to 67 (13%).<h4>Conclusions</h4>In this era of targeted therapies, characterizing the proportion of patients with hcc that would be eligible for such therapies is important. In our experience, referred patients are commonly Asian men with an acceptable hepatic reserve by Child-Pugh score, who have been diagnosed by clinical criteria alone. Most patients were offered no further therapy. Moving forward, accurate and systematic documentation of staging, performance status, and Child-Pugh score per the Barcelona Clinic Liver Cancer staging protocol will be imperative to best identify patients who may benefit most from sorafenib or available clinical trials, and to subsequently evaluate the population-based impact of the introduction of such therapies in patients with advanced hcc.
The synthesis, photophysical and biological characterization of a small library of fluorescent 5-HT(3) receptor ligands is described. Several of these novel granisetron conjugates have high quantum yields and show high affinity for the human 5-HT(3)AR.
Also flagged:Tryptophanyl-tRNA SynthetasePhosphorylationTrpRScervicalCCcancers
Journal Article2011-12-01✓ 1 SnippetPaley EL.
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Tryptophanyl-tRNA synthetase (TrpRS) expression alters in colorectal (CRC), pancreatic (PC), and cervical (CC) cancers. Here, phosphorylation of unfolded TrpRS and its fragments is stimulated by human cancer sera (CS; n = 13) and serum of rabbit tumor induced by Rous sarcoma virus, unaffected by donor sera (NS; 11/15) and abolished by alkaline phosphatase. At 20 years of follow-up, serum-inducible TrpRS phosphorylation found years before healthy donors (3/15) diagnosed with PC, CRC, or leukemia. I have examined a specificity of serum-inducible TrpRS phosphorylation and found, surprisingly, that serine phosphorylation of unfolded TrpRS is stimulated by anti-TrpRS rabbit antisera but is unaffected by rabbit nonimmune sera and antisera to other antigens. Anti-TrpRS immunoglobulin G (IgG) inhibits phosphorylation of full-length TrpRS and stimulates phosphorylation of its 20-kDa fragment. Phosphorylation of this fragment is stimulated also by CS but not NS. 2-Mercaptoethanol and cyclic AMP exerted synergistic inhibitory effect on TrpRS phosphorylation. Anti-TrpRS sera and casein act as chaperones increasing TrpRS phosphorylation through refolding. Histone-specific protein kinase activity in CS (n = 44) and anti-TrpRS sera was lower than that in NS (n = 11), rabbit nonimmune sera and antisera to other antigens. TrpRS inhibitors, tryptamine, and tryptophanol stimulate in vivo accumulation of enzymatically inactive, nonphosphorylated, aggregated and anti-TrpRS IgG refoldable TrpRS. Phosphorylation of postsurgical tissues (n = 18) reveals TrpRS in ovarian cancer (OVC) and CC but not in normal placenta and liver. In OVC, TrpRS phosphorylation increase correlates with elevated tryptophan-dependent ATP-inorganic pyrophosphate exchange. Although not inducing cancer, TrpRS triggers signaling concomitant with cancer.
Journal Article2011-12-01✓ 1 SnippetSiu A, Virtanen C, Jongstra J.
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I A O 0000326)
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The PIM family of oncogenic serine/threonine kinases regulates tumour cell proliferation. To identify proliferative signaling pathways that are regulated by PIM kinases we analyzed gene expression differences in DU-145 and PC3 prostate cancer derived cells induced by treatment with the recently developed highly selective PIM kinase inhibitor M-110. This identified 97 genes the expression of which is affected by M-110 in both cell lines. We then focused on the M-110 induced up regulation of the MIG6 gene that encodes a negative regulator of EGFR signaling. Here we show that M-110 and the structurally unrelated PIM kinase inhibitor SGI-1776 up regulate MIG6 in DU-145 and PC3 cells. Knockdown of PIM-1 but not of PIM-2 or PIM-3 also up regulates MIG6 expression, which identifies MIG6 as a PIM-1 regulated gene. In agreement with the role of MIG6 protein as a negative regulator of EGFR signaling we found that M-110 treatment inhibits EGF induced EGFR activation and the activation of the downstream ERK MAPkinase pathway. The biological significance of these findings are demonstrated by the fact that co-treatment of DU-145 or PC3 cells with the EGFR tyrosine kinase inhibitor Gefitinib and M-110 or SGI-1776 has synergistic inhibitory effects on cell proliferation. These experiments define a novel biological function of PIM-1 as a co-regulator of EGFR signaling and suggest that PIM inhibitors may be used in combination therapies to increase the efficacy of EGFR tyrosine kinase inhibitors.
Also flagged:neuropsychiatric disordersbipolar disordermood disordersneuropsychiatric diseasesSchizophreniamanic-depressive illness
Journal Article2011-12-01No SnippetsMalhotra D, McCarthy S, Michaelson JJ, Vacic V, Burdick KE, Yoon S, Cichon S, Corvin A, Gary S, Gershon ES, Gill M, Karayiorgou M, Kelsoe JR, Krastoshevsky O, Krause V, Leibenluft E, Levy DL, Makarov V, Bhandari A, Malhotra AK, McMahon FJ, Nöthen MM, Potash JB, Rietschel M, Schulze TG, Sebat J.
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While it is known that rare copy-number variants (CNVs) contribute to risk for some neuropsychiatric disorders, the role of CNVs in bipolar disorder is unclear. Here, we reasoned that a contribution of CNVs to mood disorders might be most evident for de novo mutations. We performed a genome-wide analysis of de novo CNVs in a cohort of 788 trios. Diagnoses of offspring included bipolar disorder (n = 185), schizophrenia (n = 177), and healthy controls (n = 426). Frequencies of de novo CNVs were significantly higher in bipolar disorder as compared with controls (OR = 4.8 [1.4,16.0], p = 0.009). De novo CNVs were particularly enriched among cases with an age at onset younger than 18 (OR = 6.3 [1.7,22.6], p = 0.006). We also confirmed a significant enrichment of de novo CNVs in schizophrenia (OR = 5.0 [1.5,16.8], p = 0.007). Our results suggest that rare spontaneous mutations are an important contributor to risk for bipolar disorder and other major neuropsychiatric diseases.
Although G×E studies are typically based on the assumption that some individuals possess genetic variants that enhance their vulnerability to environmental adversity, the differential susceptibility perspective posits that these individuals are simply more susceptible to environmental influence than others. An important implication of this model is that those persons most vulnerable to adverse social environments are the same ones who reap the most benefit from environmental support. The present study tested several implications of this proposition. Using longitudinal data from a sample of several hundred African Americans, we found that relatively common variants of the dopamine receptor gene and the serotonin transporter gene interact with social environmental conditions to predict aggression in a manner consonant with differential susceptibility. When the social environment was adverse, individuals with these genetic variants manifested more aggression than other genotypes, whereas when the environment was supportive they demonstrated less aggression than other genotypes. Further, we found that these genetic variants interact with environmental conditions to foster various cognitive schemas and emotions in a manner consistent with differential susceptibility and that a latent construct formed by these schemas and emotions mediated the effect of gene by environment interaction on aggression.
Also flagged:cancerzincTelADROncogenesisgene expression
Journal Article2011-12-01No SnippetsSheffer M, Simon AJ, Jacob-Hirsch J, Rechavi G, Domany E, Givol D, D'Orazi G.
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Hypoxia-inducible factor 1 (HIF-1), the major transcription factor specifically activated during hypoxia, regulates genes involved in critical aspects of cancer biology, including angiogenesis, cell proliferation, glycolysis and invasion. The HIF-1a subunit is stabilized by low oxygen, genetic alteration and cobaltous ions, and its over-expression correlates with drug resistance and increased cancer mortality in various cancer types, therefore representing an important anticancer target. Zinc supplementation has been shown to counteract the hypoxic phenotype in cancer cells, in vitro and in vivo, hence, understanding the molecular pathways modulated by zinc under hypoxia may provide the basis for reprogramming signalling pathways for anticancer therapy. Here we performed genome-wide analyses of colon cancer cells treated with combinations of cobalt, zinc and anticancer drug and evaluated the effect of zinc on gene expression patterns. Using Principal Component Analysis we found that zinc markedly reverted the cobalt-induced changes of gene expression, with reactivation of the drug-induced transcription of pro-apoptotic genes. We conclude that the hypoxia pathway is a potential therapeutic target addressed by zinc that also influences tumor cell response to anticancer drug.
Also flagged:p53p63chaperonegene expressionTP53cancer
Journal Article2011-12-01No SnippetsNeilsen PM, Noll JE, Suetani RJ, Schulz RB, Al-Ejeh F, Evdokiou A, Lane DP, Callen DF.
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Mutations in the TP53 gene commonly result in the expression of a full-length protein that drives cancer cell invasion and metastasis. Herein, we have deciphered the global landscape of transcriptional regulation by mutant p53 through the application of a panel of isogenic H1299 derivatives with inducible expression of several common cancer-associated p53 mutants. We found that the ability of mutant p53 to alter the transcriptional profile of cancer cells is remarkably conserved across different p53 mutants. The mutant p53 transcriptional landscape was nested within a small subset of wild-type p53 responsive genes, suggesting that the oncogenic properties of mutant p53 are conferred by retaining its ability to regulate a defined set of p53 target genes. These mutant p53 target genes were shown to converge upon a p63 signalling axis. Both mutant p53 and wild-type p63 were co-recruited to the promoters of these target genes, thus providing a molecular basis for their selective regulation by mutant p53. We demonstrate that mutant p53 manipulates the gene expression pattern of cancer cells to facilitate invasion through the release of a pro-invasive secretome into the tumor microenvironment. Collectively, this study provides mechanistic insight into the complex nature of transcriptional regulation by mutant p53 and implicates a role for tumor-derived p53 mutations in the manipulation of the cancer cell secretome.
Hepatic osteodystrophy (HO) is the generic term defining the group of alterations in bone mineral metabolism found in patients with chronic liver disease. This paper is a global review of HO and its main pathophysiological, epidemiological and therapeutic aspects. Studies examining the most relevant information concerning the prevalence, etiological factors, diagnostic and therapeutic aspects involved in HO were identified by a systematic literature search of the PubMed database. HO generically defines overall alterations in bone mineral density (BMD) (osteoporosis or osteopenia) which appear as a possible complication of chronic liver disease. The origin of HO is multifactorial and its etiology and severity vary in accordance with the underlying liver disease. Its exact prevalence is unknown, but different studies estimate that it could affect from 20% to 50% of patients. The reported mean prevalence of osteoporosis ranges from 13%-60% in chronic cholestasis to 20% in chronic viral hepatitis and 55% in viral cirrhosis. Alcoholic liver disease is not always related to osteopenia. HO has been commonly studied in chronic cholestatic disease (primary biliary cirrhosis and primary sclerosing cholangitis). Several risk factors and pathogenic mechanisms have been associated with the loss of BMD in patients with chronic liver disease. However, little information has been discovered in relationship to most of these mechanisms. Screening for osteopenia and osteoporosis is recommended in advanced chronic liver disease. There is a lack of randomized studies assessing specific management for HO.
The prevalence of type 2 diabetes mellitus (T2DM) is higher in patients who have liver diseases such as nonalcoholic fatty liver disease, chronic viral hepatitis, hemochromatosis, alcoholic liver disease and cirrhosis. It is suggested that there is a pathogenic link between the presence of T2DM and the severity of liver injury. However, evidence related to the impact of hepatic inflammation on the development of T2DM has not yet emerged. This article provides an overview of the evidence for an increased prevalence of diabetes in a range of liver diseases, the impact of liver diseases on insulin resistance and β cell dysfunction, and the potential mechanisms whereby coexistent liver diseases exacerbate the development of T2DM.
Also flagged:Bcl-2non-alcoholic fatty liver diseasefatty liverγ-glutamyl-transpeptidasechronic liver diseaseFL
Journal Article2011-12-01✓ 1 SnippetTarantino G, Scopacasa F, Colao A, Capone D, Tarantino M, Grimaldi E, Savastano S.
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<h4>Aim</h4>To shed some light on the relationship between anti-apoptotic serum Bcl-2 concentrations and metabolic status, anthropometric parameters, inflammation indices, and non-alcoholic fatty liver disease severity were investigated in 43 young individuals with fatty liver (FL) and 41 with nonalcoholic steatohepatitis (NASH).<h4>Methods</h4>Circulating levels of Bcl-2 were detected in 84 patients with ultrasonographic findings of "bright liver" and/or hyper-transaminasemia of unknown origin and/or increase in γ-glutamyl-transpeptidase (γ-GT) strictly in the absence of other acute or chronic liver disease, whose age was not advanced, who gave consent to liver biopsy and were then divided on the basis of the histological results into two groups (43 with FL and 41 with NASH). Twenty lean subjects, apparently healthy and young, were chosen as controls.<h4>Results</h4>Serum Bcl-2 concentrations were significantly higher in the FL group than in the NASH group. Insulin resistance and γ-GT activity were significantly higher in NASH subjects. Apoptotic hepatocytes were significantly more numerous in NASH patients. NASH patients presented with larger spleens and augmented C-reactive protein (CRP) concentrations than healthy subjects. Steatosis grade at histology was similar in both NASH and FL populations. The number of apoptotic cells was significantly related to anti-apoptotic Bcl-2 protein values in FL patients. Bcl-2 serum levels positively correlated to body mass index (BMI) values (P ≤ 0.0001) but not to age of the population. Triglycerides/HDL ratio correlated well to waist circumference in males (P = 0.0008). γ-GT activity was associated with homeostatic metabolic assessment (HOMA) (P = 0.0003) and with serum ferritin (P = 0.02). Bcl-2 concentrations were not related to either spleen size or CRP values. NASH patients presented a weak negative correlation between lobular inflammation and Bcl-2 levels. A prediction by low values of serum Bcl-2 towards a greater presence of metabolically unhealthy overweight/obese patients (MUOs) was evidenced. HOMA, BMI and uric acid, in that sequence, best predicted serum Bcl-2 concentrations.<h4>Conclusion</h4>MUOs could be detected by Bcl-2 levels. By favoring the life span of hepatocytes, and enhancing triglyceride formation, the anti-apoptotic process inhibits free fatty acids toxicity in FL.
<h4>Objective</h4>To assess the potential for genetic influences on sertraline treatment efficacy for depression of Alzheimer disease (dAD). Four functional genetic variants were studied: 2 serotonin receptors (HTR2A-T102C and HTR2C-Cys23Ser), the serotonin transporter (5HTT-LPR), and brain-derived neurotrophic factor (BDNF-Val66Met). Treatment response by genotype was measured by (1) the modified Alzheimer's Disease Cooperative Study Clinical Global Impression of Change, (2) the Cornell scale for Depression in Dementia, and (3) remission of depression.<h4>Methods</h4>We utilized data from the Depression in Alzheimer's Disease Study 2 (DIADS-2), a 24-week, randomized, multicenter trial showing no significant treatment effect of sertraline on dAD. Proportional odds logistic regression and mixed effects models were used to examine the above mentioned outcome measures.<h4>Results</h4>No significant interactions were seen between any of the genetic polymorphisms and the selected outcomes above at 12 or 24 weeks.<h4>Discussion</h4>Treatment outcomes in the DIADS-2 trial were not significantly influenced by genetic variation at the loci that were assessed. Future studies should continue to examine the interaction of depression-related genetic variants with antidepressant treatment in Alzheimer disease patients with depression.
Also flagged:OX40IRF1IL-10CD40Ltumorimmune response
Journal Article2011-12-01No SnippetsBurocchi A, Pittoni P, Gorzanelli A, Colombo MP, Piconese S.
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Treg cells maintain the tumor microenvironment in an immunosuppressive state preventing an effective anti-tumor immune response. A possible strategy to overcome Treg-cell suppression focuses on OX40, a costimulatory molecule expressed constitutively by Treg cells while being induced in activated effector T cells. OX40 stimulation, by the agonist mAb OX86, inhibits Treg-cell suppression and boosts effector T-cell activation. Here we uncover the mechanisms underlying the therapeutic activity of OX86 treatment dissecting its distinct effects on Treg and on effector memory T (Tem) cells, the most abundant CD4+ populations strongly expressing OX40 at the tumor site. In response to OX86, tumor-infiltrating Treg cells produced significantly less interleukin 10 (IL-10), possibly in relation to a decrease in the transcription factor interferon regulatory factor 1 (IRF1). Tem cells responded to OX86 by upregulating surface CD40L expression, providing a licensing signal to DCs. The CD40L/CD40 axis was required for Tem-cell-mediated in vitro DC maturation and in vivo DC migration. Accordingly, OX86 treatment was no longer therapeutic in CD40 KO mice. In conclusion, following OX40 stimulation, blockade of Treg-cell suppression and enhancement of the Tem-cell adjuvant effect both concurred to free DCs from immunosuppression and activate the immune response against the tumor.
Also flagged:Dentin sialophosphoproteinDSPPdentin dysplasia type IIdentinogenesis imperfectatypes IIoligonucleotides
Journal Article2011-12-01✓ 1 SnippetWang SK, Chan HC, Rajderkar S, Milkovich RN, Uston KA, Kim JW, Simmer JP, Hu JC.
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Dentin sialophosphoprotein (DSPP) mutations cause dentin dysplasia type II (DD-II) and dentinogenesis imperfecta types II and III (DGI-II and DGI-III, respectively). We identified two kindreds with DGI-II who exhibited vertical bands of hypoplastic enamel. Both families had a previously reported DSPP mutation that segregated with the disease phenotype. Oral photographs and dental radiographs of four affected and one unaffected participant in one family and of the proband in the second family were used to document the dental phenotypes. We aligned the 33 unique allelic DSPP sequences showing variable patterns of insertions and deletions (indels), generated a merged dentin phosphoprotein (DPP) sequence that includes sequences from all DSPP length haplotypes, and mapped the known DSPP mutations in this context. Analyses of the DSPP sequence changes and their probable effects on protein expression, as well as published findings of the dental phenotype in Dspp null mice, support the hypothesis that all DSPP mutations cause pathology through dominant-negative effects. Noting that Dspp is transiently expressed by mouse pre-ameloblasts during formation of the dentino-enamel junction, we hypothesize that DSPP dominant-negative effects potentially cause cellular pathology in pre-ameloblasts that, in turn, causes enamel defects. We conclude that enamel defects can be part of the dental phenotype caused by DSPP mutations, although DSPP is not critical for dental enamel formation.
Also flagged:polo-like kinasePLK1cancerlung cancerreceptor tyrosine kinasesnuclear hormone receptors
Journal Article2011-12-01No SnippetsLiu-Sullivan N, Zhang J, Bakleh A, Marchica J, Li J, Siolas D, Laquerre S, Degenhardt YY, Wooster R, Chang K, Hannon GF, Powers S.
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RNAi screening holds the promise of systemizing the search for combination therapeutic strategies. Here we performed a pooled shRNA library screen to look for promising targets to inhibit in combination with inhibition of the mitotic regulator polo-like kinase (PLK1). The library contained ~4,500 shRNAs targeting various signaling and cancer-related genes and was screened in four lung cancer cell lines using both high (IC80) and low (IC20) amounts of the PLK1 inhibitor GSK461364. The relative abundance of cells containing individual shRNAs following drug treatment was determined by microarray analysis, using the mock treatment replicates as the normalizing reference. Overall, the inferred influences of individual shRNAs in both high and low drug treatment were remarkably similar in all four cell lines and involved a large percentage of the library. To investigate which functional categories of shRNAs were most prominent in influencing drug response, we used statistical analysis of microarrays (SAM) in combination with a filter for genes that had two or more concordant shRNAs. The most significant functional categories that came out of this analysis included receptor tyrosine kinases and nuclear hormone receptors. Through individual validation experiments, we determined that the two shRNAs from the library targeting the nuclear retinoic acid receptor gene RARA did indeed silence RARA expression and as predicted conferred resistance to GSK461364. This led us to test whether activation of RARA receptor with retinoids could sensitize cells to GSK461364. We found that retinoids did increase the drug sensitivity and enhanced the ability of PLK1 inhibition to induce mitotic arrest and apoptosis. These results suggest that retinoids could be used to enhance the effectiveness of GSK461364 and provide further evidence that RNAi screens can be effective tools to identify combination target strategies.
Also flagged:GlypicanGPC5EthanolAlcohol use disordersataxiabehavioral
Journal Article2011-12-01No SnippetsJoslyn G, Wolf FW, Brush G, Wu L, Schuckit M, White RL.
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Alcohol use disorders are influenced by many interacting genetic and environmental factors. Highlighting this complexity is the observation that large genome-wide association experiments have implicated many genes with weak statistical support. Experimental model systems, cell culture and animal, have identified many genes and pathways involved in ethanol response, but their applicability to the development of alcohol use disorders in humans is undetermined. To overcome the limitations of any single experimental system, the analytical strategy used here was to identify genes that exert common phenotypic effects across multiple experimental systems. Specifically, we (1) performed a mouse linkage analysis to identify quantitative trait loci that influence ethanol-induced ataxia; (2) performed a human genetic association analysis of the mouse-identified loci against ethanol-induced body sway, a phenotype that is not only comparable to the mouse ethanol-ataxia phenotype but is also a genetically influenced endophenotype of alcohol use disorders; (3) performed behavioral genetic experiments in Drosophila showing that fly homologs of GPC5, the member of the glypican gene family implicated by both the human and mouse genetic analyses, influence the fly's response to ethanol; and (4) discovered data from the literature demonstrating that the genetically implicated gene's expression is not only temporally and spatially consistent with involvement in ethanol-induced behaviors but is also modulated by ethanol. The convergence of these data provides strong support to the hypothesis that GPC5 is involved in cellular and organismal ethanol response and the etiology of alcohol use disorders in humans.
Also flagged:replication protein Amitosischromosomemetabolismstructuralmaintenance of chromosomes
Journal Article2011-12-01✓ 5 SnippetsAkai Y, Kurokawa Y, Nakazawa N, Tonami-Murakami Y, Suzuki Y, Yoshimura SH, Iwasaki H, Shiroiwa Y, Nakamura T, Shibata E, Yanagida M.
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…Condensinis required for…
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…Condensincontains two structural…
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…Condensinis a hetero-pentameric…
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…Condensinand the SMC2/4…
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Condensin is required for chromosome dynamics and diverse DNA metabolism. How condensin works, however, is not well understood. Condensin contains two structural maintenance of chromosomes (SMC) subunits with the terminal globular domains connected to coiled-coil that is interrupted by the central hinge. Heterotrimeric non-SMC subunits regulate SMC. We identified a novel fission yeast SMC hinge mutant, cut14-Y1, which displayed defects in DNA damage repair and chromosome segregation. It contains an amino acid substitution at a conserved hinge residue of Cut14/SMC2, resulting in diminished DNA binding and annealing. A replication protein A mutant, ssb1-418, greatly alleviated the repair and mitotic defects of cut14-Y1. Ssb1 protein formed nucleolar foci in cut14-Y1 cells, but the number of foci was diminished in cut14-Y1 ssb1-418 double mutants. Consistent with the above results, Ssb1 protein bound to single-strand DNA was removed by condensin or the SMC dimer through DNA reannealing in vitro. Similarly, RNA hybridized to DNA may be removed by the SMC dimer. Thus, condensin may wind up DNA strands to unload chromosomal components after DNA repair and prior to mitosis. We show that 16 suppressor mutations of cut14-Y1 were all mapped within the hinge domain, which surrounded the original L543 mutation site.
…It is crucial then to not overlook the genetic impact of carrying serotonin transporter (5-HTT) gene polymorphisms on development of depression, nor the possible interrelation with a BDNF polymorphism.…
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…In their case-only design study of ethnically homogenous patients diagnosed with first episode depression, Bukh and partners [239] independently associated the existence of both low activity variants of the 5-HTT-linked polymorphic region in the serotonin transporter gene and the Val66Met BDNF polymorphism with the presence of stressful life events prior to onset of depression.…
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Depression is a neuropsychiatric disorder affecting a huge percentage of the active population especially in developed countries. Research has devoted much of its attention to this problematic and many drugs have been developed and are currently prescribed to treat this pathology. Yet, many patients are refractory to the available therapeutic drugs, which mainly act by increasing the levels of the monoamines serotonin and noradrenaline in the synaptic cleft. Even in the cases antidepressants are effective, it is usually observed a delay of a few weeks between the onset of treatment and remission of the clinical symptoms. Additionally, many of these patients who show remission with antidepressant therapy present a relapse of depression upon treatment cessation. Thus research has focused on other possible molecular targets, besides monoamines, underlying depression. Both basic and clinical evidence indicates that depression is associated with several structural and neurochemical changes where the levels of neurotrophins, particularly of brain-derived neurotrophic factor (BDNF), are altered. Antidepressants, as well as other therapeutic strategies, seem to restore these levels. Neuronal atrophy, mostly detected in limbic structures that regulate mood and cognition, like the hippocampus, is observed in depressed patients and in animal behavioural paradigms for depression. Moreover, chronic antidepressant treatment enhances adult hippocampal neurogenesis, supporting the notion that this event underlies antidepressants effects. Here we review some of the preclinical and clinical studies, aimed at disclosing the role of neurotrophins in the pathophysiological mechanisms of depression and the mode of action of antidepressants, which favour the neurotrophic/neurogenic hypothesis.
Also flagged:beta thalassemiadeferoxamineinfectionscongestive heart failurediabetes mellitusiron
Journal Article2011-12-01✓ 3 SnippetsKarimi M, Emadmarvasti V, Hoseini J, Shoja L.
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…grade of liverhemochromatosisor pre bone…
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…iron overload andhemochromatosis[ 10 ].…
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…and IV liverhemochromatosis.…
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<h4>Objective</h4>Beta thalassemia major is a prevalent hereditary disease in Mediterranean region especially Iran. Early blood transfusion is necessary for most of the patients and frequent transfusion can cause various medical problems for the patients. The aim of this study was to find major causes of hospital admission in beta thalassemia major patients to reach the accurate preventive and therapeutic plans for these patients.<h4>Methods</h4>Four hundred twenty six patients were admitted to the Nemazee Hospital (the main University referral Hospital Center affiliated to Shiraz University of Medical Sciences in Fars Province, southern Iran) during 3 years period (January 2007 to January 2010). A questionnaire was filled containing age, gender, hemoglobin level, frequency of blood transfusions, deferoxamine injection, cause of hospital admission and hospital course.<h4>Findings</h4>The mean age of patients was 11.28 years. The mean serum ferritin level was 1820±749 µg/lit. Two hundred fifty five (59.75%) patients were male and 171 (40.25%) patients were female. The top five most prevalent causes of hospital admission were splenectomy (21.8%), infections (19.9%), congestive heart failure (19.0%), diabetes mellitus (13.4%), and Liver biopsy (11.5%). (P=0.0002)<h4>Conclusion</h4>Results of this study revealed that infections and complications due to iron overload are major causes of hospital admission in beta thalassemia major patients.
Also flagged:fluorinebromineiodinehalogenfluorobehavioral
Journal Article2011-12-01No SnippetsFitzsimmons JM, Lever JR, Lever SZ.
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Eight halogenated <i>N,N</i>'-diphenethylethylenediamines were synthesized, characterized and evaluated for σ<sub>1</sub> receptor binding affinity in vitro. Measurements of lipophilicity also were obtained. The substitution pattern on one of the aromatic rings remained constant as 3,4-dichloro, while the substituents on the other aromatic ring were varied to include fluorine, bromine or iodine in either the 2-, 3- or 4- positions. Two main structure activity relationships were observed. First, halogen substitution on the 3- or 4-positions of the aromatic ring conferred higher binding affinities (<i>K</i><sub>i</sub> values 6.35 - 15.82 nM) than the corresponding substitutions at the 2-position (<i>K</i><sub>i</sub> values 12.08 - 43.15 nM). Second, derivatives containing either a bromo or fluoro substituent at a given position showed higher σ<sub>1</sub> receptor binding affinities than derivatives with a corresponding iodo substituent. The data indicate that σ<sub>1</sub> receptor affinity for this structural series is sensitive to steric bulk at the 2-position. Log <i>k</i>'<sub>w</sub> measurements for the halogenated <i>N,N</i>'-diphenethylethylenediamines were determined by high performance liquid chromatography, and varied from 2.54 - 3.71. In particular, the 3-fluoro analog exhibited a log <i>k</i>'<sub>w</sub> = 2.54 accompanied by a σ<sub>1</sub> receptor <i>K</i><sub>i</sub> = 7.8 nM. These novel N,N'-diphenethylethylenediamines warrant further investigation in behavioral assays, and radiolabeled versions may prove suitable for in vivo studies of σ<sub>1</sub> receptors.
Also flagged:Collagenmineralhydroxyapatiteapatitebone formationmineralization
Journal Article2011-12-01No SnippetsSheikh FA, Kanjwal MA, Kanjwal MA, Macossay J, Muhammad MA, Cantu T, Barakat NA, Kim HY.
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In the present study, we aimed to produce mineralized-collagen by hydrothermal process. A simple method not depending on additional foreign chemicals has been employed to isolate the mineralized-collagen fibers from bovine waste. The process of extraction involves the use of hydrothermal method from available bovine bones. The structural and morphological properties of the collagen fibers were characterized by using scanning electron microscopy and transmission electron microscopy. These results indicated well received collagen fibers, having a diameter less than 1 <i>μ</i>m and with established mineral content in the individual fibers. The X-ray diffraction showed the crystalline feature of the obtained nano-compounds. The thermo gravimetric analysis was used to differentiate between the collagen and mineral parts of obtained product. Overall, the results generously indicated production of well received collagen fibers from bovine bones.
Also flagged:organizationmineralbone diseaseosteoporosisdegradationosteopetrosis
Journal Article2011-12-01No SnippetsTadano S, Giri B.
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To understand the characteristics of bone at the tissue level, the structure, organization and mechanical properties of the underlying levels down to the nanoscale as well as their mutual interactions need to be investigated. Such information would help understand changes in the bone properties including stiffness, strength and toughness and provide ways to assess the aged and diseased bones and the development of next generation of bio-inspired materials. X-ray diffraction techniques have gained increased interest in recent years as useful non-destructive tools for investigating the nanostructure of bone. This review provides an overview on the recent progress in this field and briefly introduces the related experimental approach. The application of x-ray diffraction to elucidating the structural and mechanical properties of mineral crystals in bone is reviewed in terms of characterization of <i>in situ</i> strain, residual stress-strain and crystal orientation.