Heparan sulfate proteoglycans are key regulators of complex molecular networks due to the interaction of their sugar chains with a large number of partner proteins, which in humans number more than 200 (Ori, A., Wilkinson, M. C., and Fernig, D. G. (2008) The heparanome and regulation of cell function: structures, functions and challenges. Front. Biosci. 13, 4309-4338). We developed a method to selectively label residues involved in heparin binding that matches the requirements for medium/high throughput applications called the "Protect and Label" strategy. This is based on the protection against chemical modification given by heparin/heparan sulfate to the residues located in the heparin-binding site. Thus, analysis of fibroblast growth factor-2 bound to heparin and incubated with N-hydroxysuccinimide acetate showed that lysines involved in the sugar binding are protected against chemical modification. Moreover following release from heparin, the protected lysine side chains may be specifically labeled with N-hydroxysuccinimide biotin. After protein digestion, the biotinylated peptides were readily isolated and identified by MALDI-Q-TOF mass spectrometry. The analysis of labeled peptides obtained from three well characterized heparin-binding proteins with very different heparin-binding sites, fibroblast growth factor-2, platelet factor-4, and pleiotrophin demonstrates the success of this new approach, which thus provides a rapid and reliable procedure to identify heparin-binding sites.
Also flagged:depressionmajor depressionserotoninageingneurological disordermental disorder
Journal Article2009-06-30✓ 1 SnippetRitchie K, Jaussent I, Stewart R, Dupuy AM, Courtet P, Ancelin ML, Malafosse A.
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…5-HTT…
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<h4>Objective</h4>Neurobiological and clinical studies suggest that childhood maltreatment may result in functional and structural nervous system changes that predispose the individual to depression. This vulnerability appears to be modulated by a polymorphism in the serotonin gene-linked promoter region (5-HTTLPR). Little is known, however, about the persistence of this vulnerability across the life span, although clinical studies of adult populations suggest that gene-environment interaction may diminish with aging.<h4>Method</h4>Depressive symptomatology and adverse and protective childhood events were examined in a population of 942 persons aged 65 years and older, taking into account sociodemographic characteristics and proximal competing causes of depression (widowhood, recent life events, vascular and neurologic disorder, and disability). Subjects were recruited between March 1999 and February 2001 and were diagnosed as depressed if they met 1 of 3 criteria: a diagnosis of major depression on the Mini-International Neuropsychiatric Interview, a score higher than 16 on the Center for Epidemiologic Studies-Depression Scale, or current treatment with an antidepressant.<h4>Results</h4>Exposure to traumatic events in childhood doubled the risk of late-life depression and increased the risk of repeated episodes. Not all events were found to be pathogenic; significant risk was associated with excessive sharing of parental problems, poverty or financial difficulties, mental disorder in parents, excessive physical punishment, verbal abuse from parents, humiliation, and mistreatment by an adult outside the family. Interactions were observed between the 5-HTTLPR long (L) allele, poverty, and excessive sharing of parental problems.<h4>Conclusions</h4>Certain types of childhood trauma continue to constitute risk factors for depression in old age, outweighing more proximal causes. Gene environment vulnerability interaction is linked in older age to the L-carrying genotype, modulating the effects of general environmental conditions rather than aggressive acts on the individual, perhaps due to increased cardiac reactivity.
Also flagged:Peroxiredoxin 6cystic fibrosisCFoxygenlipidsuperoxide dismutases
Journal Article2009-06-29✓ 5 SnippetsTrudel S, Kelly M, Fritsch J, Nguyen-Khoa T, Thérond P, Couturier M, Dadlez M, Debski J, Debski J, Touqui L, Vallée B, Ollero M, Edelman A, Brouillard F.
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…These data indicate that the PQ-induced population of Prdx6 observed only in Cftr+/+ mice does not contain the overoxidized cysteine, but only its reduced form.…
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…and peroxiredoxin 6 (Prdx6).…
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…gel analysis ofPrdx6revealed one main…
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…lung and presentPrdx6as a key…
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…Prdx6, Oxidative Stress in…
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Oxidative stress plays a prominent role in the pathophysiology of cystic fibrosis (CF). Despite the presence of oxidative stress markers and a decreased antioxidant capacity in CF airway lining fluid, few studies have focused on the oxidant/antioxidant balance in CF cells. The aim of the current study was to investigate the cellular levels of reactive oxygen species (ROS), oxidative damage and enzymatic antioxidant defenses in the lung of Cftr-knockout mice in basal conditions and as a response to oxidative insult.The results show that endogenous ROS and lipid peroxidation levels are higher in Cftr(-/-) lung when compared to wild-type (Cftr(+/+)) in basal conditions, despite a strong enzymatic antioxidant response involving superoxide dismutases, glutathione peroxidases and peroxiredoxin 6 (Prdx6). The latter has the unique capacity to directly reduce membrane phospholipid hydroperoxides (PL-OOH). A dramatic increase in PL-OOH levels in Cftr(-/-) lung consecutive to in vivo oxidative challenge by paraquat (PQ) unmasks a susceptibility to phospholipid peroxidation. PQ strongly decreases Prdx6 expression in Cftr(-/-) mice compared to Cftr(+/+). Similar results were obtained after P. aeruginosa LPS challenge. Two-dimensional gel analysis of Prdx6 revealed one main molecular form in basal conditions and a PQ-induced form only detected in Cftr(+/+) lung. Mass spectrometry experiments suggested that, as opposed to the main basal form, the one induced by PQ is devoid of overoxidized catalytic Cys47 and could correspond to a fully active form that is not induced in Cftr(-/-) lung. These results highlight a constitutive redox imbalance and a vulnerability to oxidative insult in Cftr(-/-) lung and present Prdx6 as a key component in CF antioxidant failure. This impaired PL-OOH detoxification mechanism may enhance oxidative damage and stress-related signaling, contributing to an exaggerated inflammatory response in CF lung.
Also flagged:TcrbcSresponse to droughtphotosynthesisreverse transcriptionwatergene expression
Journal Article2009-06-29No SnippetsBae H, Sicher RC, Kim MS, Kim SH, Strem MD, Melnick RL, Bailey BA.
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Theobroma cacao (cacao) is cultivated in tropical climates and is exposed to drought stress. The impact of the endophytic fungus Trichoderma hamatum isolate DIS 219b on cacao's response to drought was studied. Colonization by DIS 219b delayed drought-induced changes in stomatal conductance, net photosynthesis, and green fluorescence emissions. The altered expression of 19 expressed sequence tags (ESTs) (seven in leaves and 17 in roots with some overlap) by drought was detected using quantitative real-time reverse transcription PCR. Roots tended to respond earlier to drought than leaves, with the drought-induced changes in expression of seven ESTs being observed after 7 d of withholding water. Changes in gene expression in leaves were not observed until after 10 d of withholding water. DIS 219b colonization delayed the drought-altered expression of all seven ESTs responsive to drought in leaves by > or = 3 d, but had less influence on the expression pattern of the drought-responsive ESTs in roots. DIS 219b colonization had minimal direct influence on the expression of drought-responsive ESTs in 32-d-old seedlings. By contrast, DIS 219b colonization of 9-d-old seedlings altered expression of drought-responsive ESTs, sometimes in patterns opposite of that observed in response to drought. Drought induced an increase in the concentration of many amino acids in cacao leaves, while DIS 219b colonization caused a decrease in aspartic acid and glutamic acid concentrations and an increase in alanine and gamma-aminobutyric acid concentrations. With or without exposure to drought conditions, colonization by DIS 219b promoted seedling growth, the most consistent effects being an increase in root fresh weight, root dry weight, and root water content. Colonized seedlings were slower to wilt in response to drought as measured by a decrease in the leaf angle drop. The primary direct effect of DIS 219b colonization was promotion of root growth, regardless of water status, and an increase in water content which it is proposed caused a delay in many aspects of the drought response of cacao.
Also flagged:Hemojuvelinbone morphogenic protein-4HJVglycosylphosphatidylinositolbone morphogenic proteinsBMPs
Journal Article2009-06-29No SnippetsZhang AS, Yang F, Wang J, Tsukamoto H, Enns CA.
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Hemojuvelin (HJV) is a glycosylphosphatidylinositol-linked protein and binds both bone morphogenic proteins (BMPs) and neogenin. Cellular HJV acts as a BMP co-receptor to enhance the transcription of hepcidin, a key iron regulatory hormone secreted predominantly by liver hepatocytes. In this study we characterized the role of neogenin in HJV-regulated hepcidin expression. Both HJV and neogenin were expressed in liver hepatocytes. Knockdown of neogenin decreased BMP4-induced hepcidin mRNA levels by 16-fold in HJV-expressing HepG2 cells but only by about 2-fold in cells transfected with either empty vector or G99V mutant HJV that does not bind BMPs. Further studies indicated that disruption of the HJV-neogenin interaction is responsible for a marked suppression of hepcidin expression. Moreover, in vivo studies showed that hepatic hepcidin mRNA could be significantly suppressed by blocking the interaction of HJV with full-length neogenin with a soluble fragment of neogenin in mice. Together, these results suggest that the HJV-neogenin interaction is required for the BMP-mediated induction of hepcidin expression when HJV is expressed. Combined with our previous studies, our results support that hepatic neogenin possesses two functions, mediation of cellular HJV release, and stimulation of HJV-enhanced hepcidin expression.
Also flagged:PolyglutaminephospholipidsHuntingtinHuntington's diseasemembraneslipid
Journal Article2009-06-29✓ 1 SnippetKegel KB, Sapp E, Alexander J, Valencia A, Reeves P, Li X, Masso N, Sobin L, Aronin N, DiFiglia M.
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Abstract)
…Here we show that endogenous huntingtin from normal (Hdh(7Q/7Q)) mouse brain and mutant huntingtin from Huntington's disease (Hdh(140Q/140Q)) mouse brain bound to large unilamellar vesicles containing phosphoinositol (PI) PI 3,4-bisphosphate, PI 3,5-bisphosphate, and PI 3,4,5-triphosphate [PI(3,4,5)P3].…
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Huntingtin has an expanded polyglutamine tract in patients with Huntington's disease. Huntingtin localizes to intracellular and plasma membranes but the function of huntingtin at membranes is unknown. Previously we reported that exogenously expressed huntingtin bound pure phospholipids using protein-lipid overlays. Here we show that endogenous huntingtin from normal (Hdh(7Q/7Q)) mouse brain and mutant huntingtin from Huntington's disease (Hdh(140Q/140Q)) mouse brain bound to large unilamellar vesicles containing phosphoinositol (PI) PI 3,4-bisphosphate, PI 3,5-bisphosphate, and PI 3,4,5-triphosphate [PI(3,4,5)P3]. Huntingtin interactions with multivalent phospholipids were similar to those of dynamin. Mutant huntingtin associated more with phosphatidylethanolamine and PI(3,4,5)P3 than did wild-type huntingtin, and associated with other phospholipids not recognized by wild-type huntingtin. Wild-type and mutant huntingtin also bound to large unilamellar vesicles containing cardiolipin, a phospholipid specific to mitochondrial membranes. Maximal huntingtin-phospholipid association required inclusion of huntingtin amino acids 171-287. Endogenous huntingtin recruited to the plasma membrane in cells that incorporated exogenous PI 3,4-bisphosphate and PI(3,4,5)P3 or were stimulated by platelet-derived growth factor or insulin growth factor 1, which both activate PI 3-kinase. These data suggest that huntingtin interacts with membranes through specific phospholipid associations and that mutant huntingtin may disrupt membrane trafficking and signaling at membranes.
…Treatment of neonatalhemochromatosiswith exchange transfusion…
Abstract)
…survival in neontatalhemochromatosis(NH) diagnosed postnatally…
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<h4>Objective</h4>To determine if immunomodulatory treatment including intravenous immunoglobulin (IVIG) can favorably affect survival in neontatal hemochromatosis (NH) diagnosed postnatally because it can effectively prevent occurrence of NH when applied during gestations at risk.<h4>Study design</h4>We treated 16 newborn infants with liver failure due to NH with high-dose IVIG, in combination with exchange transfusion in 13 (ET/IVIG), and compared the outcome with 131 historical controls treated conventionally.<h4>Results</h4>The severity of liver disease as estimated by prothrombin time was similar in the subjects receiving ET/IVIG and the historical controls, and the medical therapy was equivalent with the exception of the ET/IVIG therapy. Twelve subjects (75%) had good outcome, defined as survival without liver transplantation, whereas good outcome was achieved in only 17% (23/131) of historical control patients (P < .001). Four subjects died, 2 without and 2 after liver transplant. Survivors were discharged 6 to 90 days after receiving ET/IVIG therapy, and those followed for more than 1 year are within normal measures for growth, development, and liver function.<h4>Conclusions</h4>Immune therapy with ET/IVIG appears to improve the outcome and reduce the need for liver transplantation in patients with NH.
Also flagged:reproductionpneumococcal diseasepolysaccharideinvasive pneumococcal diseaseinfectionDCC1
Journal Article2009-06-27No SnippetsHoti F, Erästö P, Leino T, Auranen K.
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<h4>Background</h4>Day care centre (DCC) attendees play a central role in maintaining the circulation of Streptococcus pneumoniae (pneumococcus) in the population. Exposure within families and within DCCs are the main risk factors for colonisation with pneumococcal serotypes in DCC attendees.<h4>Methods</h4>Transmission of serotype specific carriage was analysed with a continuous time event history model, based on longitudinal data from day care attendees and their family members. Rates of acquisition, conditional on exposure, were estimated in a Bayesian framework utilising latent processes of carriage. To ensure a correct level of exposure, non-participating day care attendees and their family members were included in the analysis. Posterior predictive simulations were used to quantify transmission patterns within day care cohorts, to estimate the basic reproduction number for pneumococcal carriage in a population of day care cohorts, and to assess the critical vaccine efficacy against carriage to eliminate pneumococcal transmission.<h4>Results</h4>The model, validated by posterior predictive sampling, was successful in capturing the strong temporal clustering of pneumococcal serotypes in the day care cohorts. In average 2.7 new outbreaks of pneumococcal carriage initiate in a day care cohort each month. While 39% of outbreaks were of size one, the mean outbreak size was 7.6 individuals and the mean length of an outbreak was 2.8 months. The role of families in creating and maintaining transmission was minimal, as only 10% of acquisitions in day care attendees were from family members. Considering a population of day care cohorts, a child-to-child basic reproduction number was estimated as 1.4 and the critical vaccine efficacy against acquisition of carriage as 0.3.<h4>Conclusion</h4>Pneumococcal transmission occurs in serotype specific outbreaks of carriage, driven by within-day-care transmission and between-serotype competition. An amplifying effect of the day care cohorts enhances the spread of pneumococcal serotypes within the population. The effect of vaccination, in addition to reducing susceptibility to pneumococcal carriage in the vaccinated, induces a herd effect, thus creating a counter-effect to the amplifying effect of the cohort. Consequently, the critical vaccine efficacy against carriage, required for elimination of transmission, is relatively low. Use of pneumococcal conjugate vaccines is expected to induce a notable herd protection against pneumococcal disease.
Also flagged:chemokinesPolymerChemokineInterleukin-10immune response-
Journal Article2009-06-27No SnippetsSingh A, Singh A, Suri S, Roy K.
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Polymer-based, injectable systems that can simultaneously deliver multiple bioactive agents in a controlled manner could significantly enhance the efficacy of next generation therapeutics. For immunotherapies to be effective, both prophylactically or therapeutically, it is not only critical to drive the antigen (Ag)-specific immune response strongly towards either T helper type 1 (Th1) or Th2 phenotype, but also to promote recruitment of a high number of antigen-presenting cells (APCs) at the site of immunization. We have recently reported a microparticle-based system capable of simultaneously delivering siRNA and DNA to APCs. Here we present an in-situ crosslinkable, injectable formulation containing dendritic cell (DC)-chemo-attractants and dual-mode DNA-siRNA loaded microparticles to attract immature DCs and simultaneously deliver, to the migrated cells, immunomodulatory siRNA and plasmid DNA antigens. These low crosslink density hydrogels were designed to degrade within 2-7 days in vitro and released chemokines in a sustained manner. Chemokine carrying gels attracted 4-6 folds more DCs over a sustained period in vitro, compared to an equivalent bolus dose. Interestingly, migrated DCs were able to infiltrate the hydrogels and efficiently phagocytose the siRNA-DNA carrying microparticles. Hydrogel embedded microparticles co-delivering Interleukin-10 siRNA and plasmid DNA antigens exhibited efficient Interleukin-10 gene knockdown in migrated primary DCs in vitro.
Also flagged:insulinEnterostatinpeptidesecretionhepatomaScamp2
Journal Article2009-06-27No SnippetsPark M, Farrell J, Lemmon K, York DA.
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Enterostatin is a peptide that regulates dietary fat intake in rodents and inhibits insulin secretion from pancreatic beta cells. Microarray studies of the genomic response of both a human hepatoma cell line (HepG2 cells) and a mouse hypothalamic cell line (GT1-7 cells) to enterostatin suggested that it might regulate protein trafficking. Using semi-quantitative real-time PCR and Western blot analysis, we confirmed that enterostatin upregulated Scamp2 and down regulated Dynamin2 in these cell lines. The receptor for enterostatin is the F1-ATPase beta subunit. We transfected HepG2 cells with either a green fluorescent protein (GFP) tagged F1-ATPase beta subunit or a red fluorescent protein (RFP) tagged F1-ATPase alpha subunit to study the effects of enterostatin on translocation of its own receptor protein. Enterostatin induced movement of GFP-beta subunit to the cell periphery area but did not have any effect on the localization of RFP-alpha subunit protein in HepG2. As Scamp2 is involved in glucose uptake in mouse Beta-TC6 insulinoma cells we tested enterostatin's effect in Beta-TC6 cells. Glucose stimulated insulin release was inhibited by enterostatin as reported previously. Using siRNA to Scamp2 did not change glucose stimulated insulin release but siRNA to Dynamin2 and dominant negative Dynamin2 (Dyn K44A) inhibited glucose stimulated insulin release and abolished the response to enterostatin. This suggests enterostatin inhibits glucose stimulated insulin release in pancreatic beta cells through down regulation of Dynamin2. This study also suggests that enterostatin might have a more generalized effect on protein trafficking in various cells.
The development of materials to support bone regeneration requires flexible fabrication technologies able to tailor chemistry and architecture for specific applications. In this work we describe the preparation of ceramic-based inks for robotic-assisted deposition (robocasting) using Pluronic F-127 solutions. This approach allows the preparation of pseudoplastic inks with solid contents ranging between 30 and 50 vol.%, enabling them to flow through a narrow printing nozzle while supporting the weight of the printed structure. Ink formulation does not require manipulation of the pH or the use of highly volatile organic components. Therefore, the approach can be used to prepare materials with a wide range of compositions, and here we use it to build hydroxyapatite (HA), beta-tricalcium phosphate (beta-TCP) and biphasic (HA/beta-TCP) structures. The flow of the inks is controlled by the Pluronic content and the particle size distribution of the ceramic powders. The use of wide size distributions favors flow through the narrow printing nozzles and we have been able to use printing nozzles as narrow as 100 microm in diameter, applying relatively low printing pressures. The microporosity of the printed lines increases with increasing Pluronic content and lower sintering temperatures. Microporosity can play a key role in determining the biological response to the materials, but it also affects the strength of the structure.
Also flagged:olfactomedin domain-containingolfactomedinglycoproteinsolfactomedin domain-containing proteinsneurogenesiscell-cell adhesion
Journal Article2009-06-26No SnippetsTomarev SI, Nakaya N.
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A family of olfactomedin domain-containing proteins consists of at least 13 members in mammals. Although the first protein belonging to this family, olfactomedin, was isolated and partially characterized from frog olfactory neuroepithelim almost 20 years ago, the functions of many family members remain elusive. Most of the olfactomedin domain-containing proteins, similar to frog olfactomedin, are secreted glycoproteins that demonstrate specific expression patterns. Other family members are membrane-bound proteins that may serve as receptors. More than half of the olfactomedin domain-containing genes are expressed in neural tissues. Data obtained over the last several years demonstrate that olfactomedin domain-containing proteins play important roles in neurogenesis, neural crest formation, dorsal ventral patterning, cell-cell adhesion, cell cycle regulation, and tumorigenesis and may serve as modulators of critical signaling pathways (Wnt, bone morphogenic protein). Mutations in two genes encoding myocilin and olfactomedin 2 were implicated in glaucoma, and a growing number of evidence indicate that other genes belonging to the family of olfactomedin domain-containing proteins may contribute to different human disorders including psychiatric disorders. In this review, we summarize recent advances in understanding the possible roles of these proteins with special emphasis on the proteins that are preferentially expressed and function in neural tissues.
Also flagged:lipidCrohn's diseaseschizophreniaGRAILsynapsespathogenesis
Journal Article2009-06-26No SnippetsRaychaudhuri S, Plenge RM, Rossin EJ, Ng AC, International Schizophrenia Consortium, Purcell SM, Sklar P, Scolnick EM, Xavier RJ, Altshuler D, Daly MJ.
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Translating a set of disease regions into insight about pathogenic mechanisms requires not only the ability to identify the key disease genes within them, but also the biological relationships among those key genes. Here we describe a statistical method, Gene Relationships Among Implicated Loci (GRAIL), that takes a list of disease regions and automatically assesses the degree of relatedness of implicated genes using 250,000 PubMed abstracts. We first evaluated GRAIL by assessing its ability to identify subsets of highly related genes in common pathways from validated lipid and height SNP associations from recent genome-wide studies. We then tested GRAIL, by assessing its ability to separate true disease regions from many false positive disease regions in two separate practical applications in human genetics. First, we took 74 nominally associated Crohn's disease SNPs and applied GRAIL to identify a subset of 13 SNPs with highly related genes. Of these, ten convincingly validated in follow-up genotyping; genotyping results for the remaining three were inconclusive. Next, we applied GRAIL to 165 rare deletion events seen in schizophrenia cases (less than one-third of which are contributing to disease risk). We demonstrate that GRAIL is able to identify a subset of 16 deletions containing highly related genes; many of these genes are expressed in the central nervous system and play a role in neuronal synapses. GRAIL offers a statistically robust approach to identifying functionally related genes from across multiple disease regions--that likely represent key disease pathways. An online version of this method is available for public use (http://www.broad.mit.edu/mpg/grail/).
Also flagged:behavioralcognitionage-related cognitive declineGFPAIDSmacular degeneration
Journal Article2009-06-26No SnippetsKUANG H, WANG PL, TSIEN JZ.
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Considering the great physiological and behavioral similarities with humans, monkeys represent the ideal models not only for the study of complex cognitive behavior but also for the preclinical research and development of novel therapeutics for treating human diseases. Various powerful genetic technologies initially developed for making mouse models are being explored for generating transgenic primate models. We review the latest genetic engineering technologies and discuss the potentials and limitations for systematic production of transgenic primates.
Also flagged:deathstress kinaseheat-aggregated proteinsproteasomechaperoneskinase
Journal Article2009-06-26✓ 1 SnippetBellmann K, Charette SJ, Nadeau PJ, Poirier DJ, Loranger A, Landry J.
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The cellular response to heat shock (HS) is a paradigm for many human diseases collectively known as "protein conformation diseases" in which the accumulation of misfolded proteins induces cell death. Here, we analyzed how cells having a different apoptotic threshold die subsequent to a treatment with HS. Cells with a low apoptotic threshold mainly induced apoptosis through activation of conventional stress kinase signaling pathways. By contrast, cells with a high apoptotic threshold also died by apoptosis but likely after the accumulation of heat-aggregated proteins as revealed by the formation of aggresomes in these cells, which were associated with the generation of atypical nuclear deformations. Inhibition of the proteasome or expression of an aggregation prone protein produced similar nuclear alterations. Furthermore, elevated levels of chaperones markedly suppressed both HS-induced nuclear deformations and apoptosis induced upon protein aggregation whereas they had little effect on stress kinase-mediated apoptosis. We conclude that the relative contribution of stress signaling pathways and the accumulation of protein aggregates to cell death by apoptosis is related to the innate sensitivity of cells to deadly insults.
Also flagged:Alzheimer's diseasepathogenesisbindingoxygenmembranepore
Journal Article2009-06-26✓ 2 SnippetsBredesen DE.
In-Text Gene Mentions
I A O 0000606)
…(d)ATP-binding: deoxyadenosine triphosphate binding; (D664A): aspartate residue 664 mutated to alanine; AD: Alzheimer's disease; AICD: amyloid precursor protein intracytoplasmic domain; APP: amyloid precursor protein; Aβ: amyloid-β peptide; Apaf-1: apoptosis activating factor-1; APLP1: APP-like protein 1; APLP2: APP-like protein 2; Arg341: arginine residue 341; Asp: aspartic acid; Asp664: aspartic acid at residue 664 (of APP, based on APP695 numbering); Bcl-2: B-cell lymphoma gene 2; C31: carboxyterminal 31 residues; CARD: caspase activation and recruitment domain; Ced-3: cell death gene 3; ced-4: cell death gene 4; ced-9: cell death gene 9; Dab: disabled protein; DCC: deleted in colorectal cancer; DED: death effector domain; DNA: deoxyribonucleic acid; E3 ligases: E3-ubiquitin protein ligases; ER: endoplasmic reticulum; EPSP: excitatory post-synaptic potential; FADD: Fas-associated death domain protein; FLIP(L): FLICE-like inhibitory protein, long form; Glu: glutamate; I/L/V-E-X-D: isoleucine/leucine/valine-glutamate-any amino acid-aspartate; IAP: inhibitor of apoptosis protein; Jcasp: juxtamembrane fragment of APP produced by caspase cleavage and gamma-secretase cleavage; KAI1: Kangai 1 (suppression of tumorigenicity 6, prostate; CD82 antigen (R2 leukocyte antigen, antigen detected by monoclonal and antibody IA4)); LTP: long-term potentiation; Lys: lysine; Neo-epitopes: newly-exposed proteolysis-dependent epitopes; Omi/HtrA2: mitochondrial serine protease that antagonizes IAP proteins; PAK: p21-activated kinase; p3: peptide of approximately three kilodaltons, derived from APP by cleavage at the alpha-secretase site and the gamma-secretase site; p35: protein of approximately 35 kilodaltons that inhibits caspases; derived from baculovirus; P4 position: fourth amino acid aminoterminal to the cleavage site of a given protease; p75NTR: common neurotrophin receptor; pcd: programmed cell death; Ptc: patched protein; RET: rearranged during transfection; S1 and S3 pockets: pockets of the protease that interact with the P1 and P3 residues of the substrate, respectively; sAPPα: soluble fragment of APP derived from the cleavage by alpha-secretase; sAPPβ: soluble fragment of APP derived from the cleavage by beta-secretase; Smac/DIABLO: second mitochondrial activator of apoptosis protein/DIABLO protein; Unc5H2: uncoordinated gene 5 homologue 2; WD-40 domain: protein binding motif that contains ~7 regions ~40 amino acids long containing a conserved tryptophan and aspartic acid; XIAP: inhibitor of apoptosis protein X.…
I A O 0000606)
…Dab: disabled protein;DCC: deleted in colorectal…
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Extensive genetic, biochemical, and histological evidence has implicated the amyloid-beta peptide (Abeta) in Alzheimer's disease pathogenesis, and several mechanisms have been suggested, such as metal binding, reactive oxygen species production, and membrane pore formation. However, recent evidence argues for an additional role for signaling mediated by the amyloid precursor protein, APP, in part via the caspase cleavage of APP at aspartate 664. Here we review the effects and implications of this cleavage event, and propose a model of Alzheimer's disease that focuses on the critical nature of this cleavage and its downstream effects.
Also flagged:glutamateneurodegenerative diseasesneuroblastomacalciumsecretioniron
Journal Article2009-06-26✓ 5 SnippetsMitchell RM, Lee SY, Simmons Z, Connor JR.
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Abstract)
…HFE-dependent effects on glutamate uptake were confirmed in astrocytoma cell lines with endogenous expression of HFE.…
Abstract)
…We developed neuroblastoma cell lines expressing different HFE polymorphisms to explore the mechanisms behind these associations.…
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…The H63D HFE genetic variant has been repeatedly associated with a number of neurodegenerative diseases.…
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…HFE-dependent effects on glutamate uptake were confirmed in astrocytoma…
Abstract)
…neuroblastoma cell lines expressing different HFE…
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HFE gene variants are relatively common genetic variants in Caucasians. The H63D HFE genetic variant has been repeatedly associated with a number of neurodegenerative diseases. We developed neuroblastoma cell lines expressing different HFE polymorphisms to explore the mechanisms behind these associations. Here we tested the hypothesis that cells with the H63D variant have a phenotype that promotes glutamate toxicity. In support of this hypothesis, expression of H63D HFE is associated with increased calcium-induced glutamate secretion and decreased cellular glutamate uptake. The polymorphism-associated changes in glutamate secretion were mimicked by altering cellular iron. Additionally, intracellular calcium is altered in a genotype-specific manner which could further impact glutamate secretion. HFE-dependent effects on glutamate uptake were confirmed in astrocytoma cell lines with endogenous expression of HFE. The ability of minocycline and the antioxidant Trolox to increase glutamate uptake differed by HFE genotype and implicate oxidative stress in glutamate regulation. This study demonstrates HFE cellular effects that extend beyond iron regulation, and suggests that H63D HFE may promote glutamate toxicity.
Also flagged:histone deacetylase 1HDAC1HDAC2gene expressionCOMPcarboxy
Journal Article2009-06-26✓ 1 SnippetHong S, Derfoul A, Pereira-Mouries L, Hall DJ.
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…Sox6…
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The role of histone deacetylase 1 and 2 (HDAC1 and HDAC2) in regulating cartilage-specific gene expression was explored in primary human chondrocytes. HDAC1 and HDAC2 protein levels were elevated in chondrocytes from osteoarthritic patients, consistent with a down-regulation of some cartilage marker genes. When expressed in these cells, HDAC1 and HDAC2 repressed aggrecan and collagen 2(alpha1) expression but differed in their repression of collagen 9(alpha1), collagen 11(alpha1), dermatopontin, and cartilage oligomeric matrix protein (COMP). To identify the basis of these differences between HDAC1 and HDAC2, their carboxy-terminal domains (CTDs) were deleted, which led to proteins that retained enzymatic activity but were unable to repress cartilage gene expression. Further, exchange of the CTDs between HDAC1 and HDAC2 led to proteins that were enzymatically active but displayed altered target gene specificity, indicating that these CTDs can function independently of HDAC enzymatic activity, to target the HDACs to specific genes. The Snail transcription factor was identified as a mediator of HDAC1 and HDAC2 repression of the collagen 2(alpha1) gene, via its interaction with the HDAC1 and 2 CTDs. The data indicate that the CTD serves a novel function within HDAC1 and HDAC2, to mediate repression of cartilage-specific gene expression in human chondrocytes.
Also flagged:immune responseschemokineschemokine receptorscytokine receptorsTLRsgene expression
Journal Article2009-06-25No SnippetsZhong W, Fei M, Zhu Y, Zhang X.
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Dendritic cells (DC) are professional antigen-presenting cells capable of initiating primary immune responses. They have been intensively studied and are used in both basic immunology research and clinical immunotherapy. However, the genetic pathways leading to DC differentiation and maturation remain poorly understood. Using focused microarrays with oligonucletotide probes for 120 genes encoding co-stimulatory molecules, chemokines, chemokine receptors, cytokines, cytokine receptors, TLRs, and several other related molecules, we analyzed the kinetics of gene expression for the overall differentiation process of monocytes into mature DC. In parallel, we compared the transcriptional profiles in DC maturation in the presence of LPS, TNF-alpha or trimeric CD40L. We found similar transcriptional profiles for early immature DC and immature DC, respectively generated by culturing monocytes with GM-CSF and IL-4 for three or six days. We identified sets of common and stimuli-specific genes, the expression of which changed following stimulation with LPS, TNF-alpha or CD40L. A dynamic analysis of the entire DC differentiation and maturation process showed that some important inflammatory and constitutive chemokines are transcribed in both immature and mature DC. The correlative expression kinetics of the gene pairs IL1R1/IL1R2, IL15/IL15RA, DC-SIGN/ICAM-2 and DC-SIGN/ICAM-3 imply that they all play crucial roles in mediating DC functions. Thus, our analysis with focused microarrays shed light on the transcriptional kinetics of DC differentiation and maturation, and this method may also prove useful for identifying novel marker genes involved in DC functions.
Also flagged:estrogen receptorestrogenslung adenocarcinomacytoplasmnon–small cell lung cancerestradiol
Journal Article2009-06-25No SnippetsIvanova MM, Mazhawidza W, Dougherty SM, Klinge CM.
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The role of estrogens in the increased risk of lung adenocarcinoma in women remains uncertain. We reported that lung adenocarcinoma cell lines from female, but not male, patients with non-small cell lung cancer respond proliferatively and transcriptionally to estradiol (E(2)), despite equal protein expression of estrogen receptors (ER) alpha and beta. To test the hypothesis that nuclear localization of ER alpha corresponds to genomic E(2) activity in lung adenocarcinoma cells from females, cell fractionation, immunoblot, and confocal immunohistochemical microscopy were performed. We report for the first time that E(2) increases phospho-serine-118-ER alpha (P-ser118-ER alpha) and cyclin D1 (CCND1) nuclear colocalization in H1793, but not A549 lung adenocarcinoma cells, derived from a female and male patient, respectively. ER beta was primarily in the cytoplasm and mitochondria, independent of E(2) treatment, and showed no difference between H1793 and A549 cells. E(2) induced higher transcription of endogenous ER alpha-regulated CCND1 in H1793 than in A549 cells. Likewise, higher rapid, non-genomic E(2)-induced extracellular signal-regulated kinase 1/2 activation was detected in H1793 compared with A549 cells, linking extracellular signal-regulated kinase activation to increased P-ser118-ER alpha. Furthermore, E(2) increased cyclin D1 and P-ser118-ER alpha nuclear localization in H1793, but not A549 cells. Together, our results indicate that nuclear localization of P-ser118-ER alpha provides one explanation for sex-dependent differences in E(2)-genomic responses in lung adenocarcinoma cell lines.
Also flagged:Raf Kinase Inhibitory ProteinRKIPPhosphatidylethanolamine Binding ProteinRafMAP kinasecell migration
Journal Article2009-06-24✓ 1 SnippetShemon AN, Eves EM, Clark MC, Heil G, Granovsky A, Zeng L, Imamoto A, Koide S, Rosner MR.
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Abstract)
…Protein (RKIP, alsoPEBP1), a member of…
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<h4>Background</h4>Raf Kinase Inhibitory Protein (RKIP, also PEBP1), a member of the Phosphatidylethanolamine Binding Protein family, negatively regulates growth factor signaling by the Raf/MAP kinase pathway. Since an organic compound, locostatin, was reported to bind RKIP and inhibit cell migration by a Raf-dependent mechanism, we addressed the role of RKIP in locostatin function.<h4>Methods/findings</h4>We analyzed locostatin interaction with RKIP and examined the biological consequences of locostatin binding on RKIP function. NMR studies show that a locostatin precursor binds to the conserved phosphatidylethanolamine binding pocket of RKIP. However, drug binding to the pocket does not prevent RKIP association with its inhibitory target, Raf-1, nor affect RKIP phosphorylation by Protein Kinase C at a regulatory site. Similarly, exposure of wild type, RKIP-depleted HeLa cells or RKIP-deficient (RKIP(-/-)) mouse embryonic fibroblasts (MEFs) to locostatin has no effect on MAP kinase activation. Locostatin treatment of wild type MEFs causes inhibition of cell migration following wounding. RKIP deficiency impairs migration further, indicating that RKIP protects cells against locostatin-mediated inhibition of migration. Locostatin treatment of depleted or RKIP(-/-) MEFs reveals cytoskeletal disruption and microtubule abnormalities in the spindle.<h4>Conclusions/significance</h4>These results suggest that locostatin's effects on cytoskeletal structure and migration are caused through mechanisms independent of its binding to RKIP and Raf/MAP kinase signaling. The protective effect of RKIP against drug inhibition of migration suggests a new role for RKIP in potentially sequestering toxic compounds that may have deleterious effects on cells.
Also flagged:probenecidHuntington's diseaseHDautosomal dominantly inherited disordermembranepathogenesis
Journal Article2009-06-24✓ 1 SnippetVamos E, Voros K, Zadori D, Vecsei L, Klivenyi P.
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Abstract)
…Huntington's disease (HD) is an autosomal dominantly inherited disorder, caused by an expanded polyglutamine region of a protein called huntingtin.…
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Huntington's disease (HD) is an autosomal dominantly inherited disorder, caused by an expanded polyglutamine region of a protein called huntingtin. The excitotoxicity, oxidative damage and altered membrane transport may have an important role in the pathogenesis of HD. Probenecid is a non-selective inhibitor of multidrug resistance-associated proteins, but it also inhibits organic anion transporters. In this study, we examined the effects of probenecid on the survival, behaviour and immunohistochemical changes in the N171-82Q transgenic mouse model of HD. After probenecid administration, the duration of survival improved by 35%. The motor activity was significantly ameliorated as compared with the control transgenic group. Probenecid treatment significantly reduced the neuronal loss and the number of neuronal intranuclear aggregates. These results suggest that probenecid may exert a neuroprotective effect by increasing the membrane transport of protective compounds, and/or inhibiting the toxic compounds.
To investigate the genetic architecture of severe obesity, we performed a genome-wide association study of 775 cases and 3197 unascertained controls at approximately 550,000 markers across the autosomal genome. We found convincing association to the previously described locus including the FTO gene. We also found evidence of association at a further six of 12 other loci previously reported to influence body mass index (BMI) in the general population and one of three associations to severe childhood and adult obesity and that cases have a higher proportion of risk-conferring alleles than controls. We found no evidence of homozygosity at any locus due to identity-by-descent associating with phenotype which would be indicative of rare, penetrant alleles, nor was there excess genome-wide homozygosity in cases relative to controls. Our results suggest that variants influencing BMI also contribute to severe obesity, a condition at the extreme of the phenotypic spectrum rather than a distinct condition.
…Therefore, we generatedPlcl1and Plcl2 double-knockout…
Abstract)
…Plcl2 double-knockout mice (Plcl1(tm1Mh); Plcl2(tm1Tta)) to gai…
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Phospholipase C-related but catalytically inactive protein (comprising PRIP-1 and PRIP-2 [officially designated PLCL1 and PLCL2]) was first identified in our laboratory, but the biological functions have remained elusive. Therefore, we generated Plcl1 and Plcl2 double-knockout mice (Plcl1(tm1Mh); Plcl2(tm1Tta)) to gain insight into the biological function. Double-knockout mice apparently grew normally and became fertile; however, during animal maintenance, we noticed that mutant couples exhibited decreased litter events and litter size, indicating dysfunction of the reproductive system. Cross-mating experiments to discriminate whether males or females were defective indicated that the cause appeared to be on the female side. Mutant female mice had an apparently smaller uterus by gross anatomical observation and had more estrous days during the cycles. Levels of serum luteinizing hormone (LH) and follicle-stimulating hormone were measured for 5-6 consecutive days and were significantly higher in the mutant, which was also confirmed by examining the secretion of LH from the explant culture of anterior pituitary glands of wild-type and double-knockout mice. These results suggest that through gonadotropin secretion, PRIP plays an important role in female reproduction.
In mammalian spermatocytes, cell division cycle protein 2 (CDC2)/cyclin B1 and the chaperone heat shock protein A2 (HSPA2) are required for the G2-->M transition in prophase I. Here, we demonstrate that in primary spermatocytes, linker histone chaperone testis/embryo form of nuclear autoantigenic sperm protein (tNASP) binds the heat shock protein HSPA2, which localizes on the synaptonemal complex of spermatocytes. Significantly, the tNASP-HSPA2 complex binds linker histones and CDC2, forming a larger complex. We demonstrate that increasing amounts of tNASP favor tNASP-HSPA2-CDC2 complex formation. Binding of linker histones to tNASP significantly increases HSPA2 ATPase activity and the capacity of tNASP to bind HSPA2 and CDC2, precluding CDC2/cyclin B1 complex formation and, consequently, decreasing CDC2/cyclin B1 kinase activity. Linker histone binding to NASP controls the ability of HSPA2 to activate CDC2 for CDC2/cyclin B1 complex formation; therefore, tNASP's role is to provide the functional link between linker histones and cell cycle progression during meiosis.
Also flagged:disulfideHepcidinpeptideironwatersepsis
Journal Article2009-06-24No SnippetsJordan JB, Poppe L, Haniu M, Arvedson T, Syed R, Li V, Kohno H, Kim H, Schnier PD, Harvey TS, Miranda LP, Cheetham J, Sasu BJ.
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Hepcidin is a tightly folded 25-residue peptide hormone containing four disulfide bonds, which has been shown to act as the principal regulator of iron homeostasis in vertebrates. We used multiple techniques to demonstrate a disulfide bonding pattern for hepcidin different from that previously published. All techniques confirmed the following disulfide bond connectivity: Cys(1)-Cys(8), Cys(3)-Cys(6), Cys(2)-Cys(4), and Cys(5)-Cys(7). NMR studies reveal a new model for hepcidin that, at ambient temperatures, interconverts between two different conformations, which could be individually resolved by temperature variation. Using these methods, the solution structure of hepcidin was determined at 325 and 253 K in supercooled water. X-ray analysis of a co-crystal with Fab appeared to stabilize a hepcidin conformation similar to the high temperature NMR structure.
Also flagged:ATF3Huntington's diseaseneurodegenerative disorderpolyglutaminegene expressiondeath
Journal Article2009-06-24✓ 5 SnippetsLiang Y, Jiang H, Ratovitski T, Jie C, Nakamura M, Hirschhorn RR, Wang X, Smith WW, Hai T, Poirier MA, Ross CA.
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Abstract)
…We have studied gene expression profiles by short oligo array using an inducible PC12 cell model expressing an N-terminal huntingtin fragment with expanded polyglutamine (Htt-N63-148Q).…
Abstract)
…with expanded polyglutamine (Htt-N63-148Q).…
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…Mutant huntingtinHtt-N63 induced cell death…
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…MutantHtt-N63 also significantly enhanc…
Abstract)
…protects against mutantHtt-N63 toxicity and knocking…
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Huntington's disease is a progressive neurodegenerative disorder caused by a polyglutamine expansion near the N-terminus of huntingtin. The mechanisms of polyglutamine neurotoxicity, and cellular responses are not fully understood. We have studied gene expression profiles by short oligo array using an inducible PC12 cell model expressing an N-terminal huntingtin fragment with expanded polyglutamine (Htt-N63-148Q). Mutant huntingtin Htt-N63 induced cell death and increased the mRNA and protein levels of activating transcription factor 3 (ATF3). Mutant Htt-N63 also significantly enhanced ATF3 transcriptional activity by a promoter-based reporter assay. Overexpression of ATF3 protects against mutant Htt-N63 toxicity and knocking down ATF3 expression reduced Htt-N63 toxicity in a stable PC12 cell line. These results indicated that ATF3 plays a critical role in toxicity induced by mutant Htt-N63 and may lead to a useful therapeutic target.
Also flagged:attention-deficit hyperactivity disorderAttention-deficit/hyperactivity disorderADHDautismschizophreniaIMMP2L
Journal Article2009-06-23✓ 4 SnippetsElia J, Gai X, Xie HM, Perin JC, Geiger E, Glessner JT, D'arcy M, deBerardinis R, Frackelton E, Kim C, Lantieri F, Muganga BM, Wang L, Takeda T, Rappaport EF, Grant SF, Berrettini W, Devoto M, Shaikh TH, Hakonarson H, White PS.
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Results)
…ADHD CNV genes associated with learning and cognition included ATM, CTNND2, GRM5, GRM7, PARK2, PTPRD and UNC13C. As an additional control to show the specificity and independence of the inclusion variables, the same CNV inclusion criteria and analysis strategies were reapplied using a large set of parent–child trios for congenital heart disease.…
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…, PTPRD andUNC13C.…
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…, PARK2 andUNC13C) with synapse…
Results)
…( CHN2 andUNC13C) with synaptosome…
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Attention-deficit/hyperactivity disorder (ADHD) is a common and highly heritable disorder, but specific genetic factors underlying risk remain elusive. To assess the role of structural variation in ADHD, we identified 222 inherited copy number variations (CNVs) within 335 ADHD patients and their parents that were not detected in 2026 unrelated healthy individuals. Although no excess CNVs, either deletions or duplications, were found in the ADHD cohort relative to controls, the inherited rare CNV-associated gene set was significantly enriched for genes reported as candidates in studies of autism, schizophrenia and Tourette syndrome, including A2BP1, AUTS2, CNTNAP2 and IMMP2L. The ADHD CNV gene set was also significantly enriched for genes known to be important for psychological and neurological functions, including learning, behavior, synaptic transmission and central nervous system development. Four independent deletions were located within the protein tyrosine phosphatase gene, PTPRD, recently implicated as a candidate gene for restless legs syndrome, which frequently presents with ADHD. A deletion within the glutamate receptor gene, GRM5, was found in an affected parent and all three affected offspring whose ADHD phenotypes closely resembled those of the GRM5 null mouse. Together, these results suggest that rare inherited structural variations play an important role in ADHD development and indicate a set of putative candidate genes for further study in the etiology of ADHD.
Also flagged:metabolismgastrointestinal diseaseGI) diseaseGI diseasepancreatitisCYP450
Journal Article2009-06-23No SnippetsSaito YA, Talley NJ.
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Pharmacogenetics is an evolving field that provides the link between an individual's genetic code and drug metabolism and drug response. This field offers the great promise of individualized medication selection and optimized dosage to maximize treatment response and to minimize adverse side effects. As our understanding of the role of the effects of genetic variants on drug metabolism and body drug processing grows, so does our ability to educate and inform our patients about expected treatment response to the medications being prescribed to them. This brief review will provide an overview of genetics, pharmacogenetics, and current and future examples of genetic variants predicting drug response in gastrointestinal disease, and the limitations and the promise of this exciting and developing field.
Also flagged:Bipolar disordermaniadepressionBipolar IhypomaniaBipolar II
Journal Article2009-06-23✓ 1 SnippetRapoport SI, Basselin M, Kim HW, Rao JS.
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Bipolar disorder (BD) is a major medical and social burden, whose cause, pathophysiology and treatment are not agreed on. It is characterized by recurrent periods of mania and depression (Bipolar I) or of hypomania and depression (Bipolar II). Its inheritance is polygenic, with evidence of a neurotransmission imbalance and disease progression. Patients often take multiple agents concurrently, with incomplete therapeutic success, particularly with regard to depression. Suicide is common. Of the hypotheses regarding the action of mood stabilizers in BD, the "arachidonic acid (AA) cascade" hypothesis is presented in detail in this review. It is based on evidence that chronic administration of lithium, carbamazepine, sodium valproate, or lamotrigine to rats downregulated AA turnover in brain phospholipids, formation of prostaglandin E(2), and/or expression of AA cascade enzymes, including cytosolic phospholipase A(2), cyclooxygenase-2 and/or acyl-CoA synthetase. The changes were selective for AA, since brain docosahexaenoic or palmitic acid metabolism, when measured, was unaffected, and topiramate, ineffective in BD, did not modify the rat brain AA cascade. Downregulation of the cascade by the mood stabilizers corresponded to inhibition of AA neurotransmission via dopaminergic D(2)-like and glutamatergic NMDA receptors. Unlike the mood stabilizers, antidepressants that increase switching of bipolar depression to mania upregulated the rat brain AA cascade. These observations suggest that the brain AA cascade is a common target of mood stabilizers, and that bipolar symptoms, particularly mania, are associated with an upregulated cascade and excess AA signaling via D(2)-like and NMDA receptors. This review presents ways to test these suggestions.
Also flagged:methylationoncogenestumor suppressor genesgene expressionmismatch repairhepatocellular carcinoma
Journal Article2009-06-23✓ 3 SnippetsBoland CR, Shin SK, Goel A.
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S I O 001029)
…These data clarified the importance of epigenetic silencing as an earlier event (UNC5C methylation), compared to genetic alterations (DCC loss) that happen at later stages in multistep colorectal carcinogenesis.57 Another interesting feature is that these hypermethylated genes are not only pathogenic events in the adenoma-to-cancer progression, but are neoplasm-specific molecular events that have the potential to be used as molecular biomarkers of pre-malignant tumors in the colon.…
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…When these data were compared with allelic losses at a second Netrin-1 receptor, DCC, we found that UNC5C methylation occurred predominantly in the earlier lesions (adenomas and early stage CRCs), whereas DCC losses occurred frequently in advanced CRCs.…
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…Normal tissues from patients who did not have HCC showed methylation at seven "group 1" loci, which included HIC-1, CASP8, GSTP1, SOCS1, RASSFIA, p16, and APC. Group 1 loci were more highly methylated than five markers in "group 2" (CDH1, RUNX3, RIZ1, SFRP2, and MINT31) or seven "group 3" (COX2, MINT1, CACNA1G, RASSF2, MINT2, Reprimo, and DCC).…
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Colorectal cancers (CRC)--and probably all cancers--are caused by alterations in genes. This includes activation of oncogenes and inactivation of tumor suppressor genes (TSGs). There are many ways to achieve these alterations. Oncogenes are frequently activated by point mutation, gene amplification, or changes in the promoter (typically caused by chromosomal rearrangements). TSGs are typically inactivated by mutation, deletion, or promoter methylation, which silences gene expression. About 15% of CRC is associated with loss of the DNA mismatch repair system, and the resulting CRCs have a unique phenotype that is called microsatellite instability, or MSI. This paper reviews the types of genetic alterations that can be found in CRCs and hepatocellular carcinoma (HCC), and focuses upon the epigenetic alterations that result in promoter methylation and the CpG island methylator phenotype (CIMP). The challenge facing CRC research and clinical care at this time is to deal with the heterogeneity and complexity of these genetic and epigenetic alterations, and to use this information to direct rational prevention and treatment strategies.
Also flagged:hormone receptorsERPRinvasive mammary carcinomaantibodiesestrogen
Journal Article2009-06-23✓ 1 SnippetPleşan DM, Georgescu CV, Ciobotea S, Pătrană N, Mitroi L, Pleşan C.
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Discussion)
…As we have seen in the present paper, the ER+/PR- fenotype cases have had low values on the Allred scale (below 6), the results being similar to those obtained through other methods (dextran coated charcoal-DCC), according to which the average level of estrogenic receptors in ER+/PR- tumors is only half of the one in ER+/PR+ tumors.…
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AIMS. Immunohistochemical evaluation of hormone receptors (ER, PR) and correlation of immunohistochemical and morpho-clinical data. METHOD. The study was performed on paraffin-embedded and HE stained tissues originating from 100 cases of invasive mammary carcinoma. Monoclonal antibodies anti-estrogen and anti progesterone receptors were used for the immunohistochemical study. The detection system was EnVision HRP and the visualization system was 3-3' diaminobenzidine tetrahydrochloride (DAB). The evaluation of the result was performed using the Allred score. REZULTS. The majority of the studied cases (57%) expressed both types of hormone receptors and in 32% of the cases the hormone receptors were completely absent. The rest of the cases presented a heterogeneous phenotype: 7% presented the ER-/PR+ type and 4%, the ER+/PR- type. Compared with the classical phenotype (ER+/PR-), ER+/PR- tumors were more frequent at patients over 50 years. The tumors with ER+/PR- were larger than the ER+/PR+ and they were of the invasive ductal carcinoma type with an Allred score for ER under 6. CONCLUSION. The predictive value is amplified when the ER status is correlated with the PR status because the heterogeneous phenotypes are identified, especially the ER+/PR- phenotype which have an aggressive behavior and the lowest response to tamoxifen therapy.
Also flagged:serotonin-transporterserotoninreuptakesertralineejaculationSLC6A4
Journal Article2009-06-22✓ 2 SnippetsSafarinejad MR.
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Abstract)
…The probability of patients responding sufficiently to sertraline with an L(A)/L(A) genotype was highest (odds ratio 4.66, 95% CI, 2.48-6.14).<h4>Conclusions</h4>These findings indicate that the genotype of 5-HTT contributes in unique ways to the variation in the outcome of PE treatment with SSRIs.…
Abstract)
…the genotype of5-HTTcontributes in unique…
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<h4>Objective</h4>To test the hypothesis that polymorphism within the gene-linked polymorphic region (5-HTTLPR) and second intron of SLC6A4 gene (STin2) is associated with selective serotonin-reuptake inhibitors (SSRIs) response in subjects with premature ejaculation (PE).<h4>Patients and methods</h4>In all, 246 men with PE were recruited in this study. They were asked to take sertraline 50 mg daily for 2 weeks, and thereafter 100 mg daily, for a 12-week treatment period. Pretreatment evaluation included history and physical examination, intravaginal ejaculatory latency time (IELT), and International Index of Erectile Function (IIEF). The efficacy of treatment was assessed using responses to IIEF, and geometric mean IELT evaluation. 5-HTTLPR was genotyped using polymerase chain reaction techniques. A repeated-measures analysis of variance of geometric mean IELT was done to test a genotype effect on treatment outcome with SSRI (sertraline).<h4>Results</h4>Of 227 participants who completed the study, 175 (77.1%) responded to sertraline (IELT >1 min). Overall the patients had a 3.7-fold (95% confidence interval, CI, 1.72-5.46) increase of the geometric mean IELT (P = 0.001). The results showed that responses were significantly better for the L(A)/L(A) genotype of the 5-HTTLPR polymorphism than for S-allele carriers (P = 0.001). The STin2 12/12 genotype was found more often in those responding to sertraline than in those not responding (P = 0.001). The probability of patients responding sufficiently to sertraline with an L(A)/L(A) genotype was highest (odds ratio 4.66, 95% CI, 2.48-6.14).<h4>Conclusions</h4>These findings indicate that the genotype of 5-HTT contributes in unique ways to the variation in the outcome of PE treatment with SSRIs.
Also flagged:hemostasisvenous thrombosiscoagulationfibrinolysisvenous thromboembolic diseasefactor V Leiden
Journal Article2009-06-22✓ 1 SnippetReiner AP, Lange LA, Smith NL, Zakai NA, Cushman M, Folsom AR.
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…SERPINC1…
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<h4>Background/objectives</h4>Age-related changes in blood coagulation and fibrinolysis are associated with increased risk of thrombotic events. Inherited deficiencies of coagulation proteins, such as factor V (FV) Leiden and prothrombin G20210A, explain a small fraction of venous thromboembolic disease (VTE). Additional genetic factors are likely to underlie the etiology of VTE, some of which may become manifest at older ages.<h4>Methods</h4>We tested 290 common SNPs within 51 thrombosis and inflammation genes for association with VTE in the Cardiovascular Health Study, a large, prospective cohort of older adults followed for up to 12 years.<h4>Results</h4>There were 184 VTE events that occurred at mean age of 78 years. TagSNPs within four genes encoding FXIII subunit A (F13A), FVII activating protease (HABP2), protease activated receptor-1 (F2R) and the urokinase receptor (PLAUR) showed the strongest evidence for association with VTE, with each gene having a global P-value < 0.05 and at least one tagSNP false discovery rate (FDR) q-value < 0.05. The rs3024409 variant allele of F13A1 was associated with 1.66-fold increased risk of VTE, while the minor alleles of HABP2 rs6585234 and rs3862019, F2R rs253061 and rs153311, and PLAUR rs344782 were each associated with lower risk of VTE (hazard ratios in the range of 0.49-0.66). Consistent with the observed protective association for VTE risk, the HABP2 rs3862019 variant allele was also associated with lower activity levels of coagulation factors FVIII, FIX, FX and plasminogen. We also confirm previously reported associations between common variants of the coagulation FII, FV, FVIII, FXI, alpha-fibrinogen and protein C genes and risk of VTE.<h4>Conclusions</h4>These findings suggest that several novel common coagulation gene variants may be related to risk of VTE in older adults. Further studies in older adults are needed to validate these findings and assess functional molecular mechanisms.
The organization of the embryonic neural plate requires coordination of multiple signal transduction pathways, including fibroblast growth factors (FGFs), bone morphogenetic proteins (BMPs), and WNTs. Many studies have suggested that a critical component of this process is the patterning of posterior neural tissues by an FGF-caudal signaling cascade. Here, we have identified a novel player, Dazap2, and show that it is required in vivo for posterior neural fate. Loss of Dazap2 in embryos resulted in diminished expression of hoxb9 with a concurrent increase in the anterior marker otx2. Furthermore, we found that Dazap2 is required for FGF dependent posterior patterning; surprisingly, this is independent of Cdx activity. Furthermore, in contrast to FGF activity, Dazap2 induction of hoxb9 is not blocked by loss of canonical Wnt signaling. Functionally, we found that increasing Dazap2 levels alters neural patterning and induces posterior neural markers. This activity overcomes the anteriorizing effects of noggin, and is downstream of FGF receptor activation. Our results strongly suggest that Dazap2 is a novel and essential branch of FGF-induced neural patterning.
Also flagged:5-Hydroxytryptamine Receptoramines5-HT receptormigraineanxietypsychosis
Journal Article2009-06-21✓ 1 SnippetPithadia AB, Jain SM.
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S I O 001029)
…Selective serotonin-reuptake inhibitors (SSRIs) antagonize the serotonin (5-hydroxytryptamine) transporter (5-HTT), and are frequently prescribed to children and adolescents to treat depression.…
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<h4>Unlabelled</h4>5-hydroxytryptamine (5-HT) has become one of the most investigated and complex biogenic amines. The main receptors and their subtypes, e.g., 5-HTI (5-HT1A, 5-HT1B, 5-HTID, 5-HTIE and 5-HT1F), 5-HT2 (5-HT2A, 5-HT2B and 5-HT2C), 5-HT3, 5-HT4, 5-HT5 (5-HT5A, 5-HT5B), 5-HT6 and 5-HT7 have been identified. Specific drugs which are capable of either selectively stimulating or inhibiting these receptor subtypes are being designed. This has generated therapeutic potentials of 5-HT receptor modulators in a variety of disease conditions. Conditions where 5-HT receptor modulators have established their use with distinct efficacy and advantages include migraine, anxiety, psychosis, obesity and cancer therapy-induced vomiting by cytotoxic drugs and radiation. Discovery of 5-HT, its biosynthesis, metabolism, physiological role and the potential of 5-HT receptor modulators in various nervous, cardiovascular and gastrointestinal tract disorders, bone growth and micturition have been discussed in this article.<h4>Keywords</h4>5-hydroxytryptamine (5-HT) receptors; Modulators; Biogenic amines.
Also flagged:TP53APCK-rasinflammatory bowel diseaseulcerative colitisCrohn's disease
Journal Article2009-06-20✓ 3 SnippetsRapozo DC, Grinmann AB, Carvalho AT, de Souza HS, Soares-Lima SC, de Almeida Simão T, de Paiva D, Abby F, Albano RM, Pinto LF.
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Abstract)
…To understand the molecular basis of colitis-associated CRC, we analyzed alterations in TP53, APC, K-ras, and DCC genes in the non-dysplastic UC and CD colon.<h4>Materials and methods</h4>Endoscopic biopsies were collected from six predefined colon sites of 35 UC and 12 CD patients for DNA extraction and genetic analysis.<h4>Results</h4>A mutation was found in codon 1141 of the APC gene of two CD patients, being somatic in one and germinative in the other.…
Title)
…Analysis of mutations in TP53, APC, K-ras, and DCC genes in the non-dysplastic mucosa of patients with inflammatory bowel disease.…
Title)
…APC, K-ras, andDCCgenes in the…
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<h4>Background and aims</h4>Patients with ulcerative colitis (UC) and Crohn's disease (CD) have a high risk for colorectal cancer (CRC). To understand the molecular basis of colitis-associated CRC, we analyzed alterations in TP53, APC, K-ras, and DCC genes in the non-dysplastic UC and CD colon.<h4>Materials and methods</h4>Endoscopic biopsies were collected from six predefined colon sites of 35 UC and 12 CD patients for DNA extraction and genetic analysis.<h4>Results</h4>A mutation was found in codon 1141 of the APC gene of two CD patients, being somatic in one and germinative in the other. The mutation seen in both patients was a base exchange of thymine for cytosine, resulting in an exchange of leucine for serine. We did not detect any mutations in the other samples analyzed.<h4>Conclusions</h4>Mutations in APC gene may occur in the non-dysplastic CD mucosa of patients with disease for more than 10 years. The follow-up of these patients will show the likelihood of mutant APC progressing to CRC in CD. Further analysis will be required for evaluating the impact of these findings in the context of cancer surveillance in inflammatory bowel disease.
Also flagged:organizationgene expressionlocalizationchromosomal regionstumorastrocytoma
Journal Article2009-06-19No SnippetsBicciato S, Spinelli R, Zampieri M, Mangano E, Ferrari F, Beltrame L, Cifola I, Peano C, Solari A, Battaglia C.
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The integration of high-throughput genomic data represents an opportunity for deciphering the interplay between structural and functional organization of genomes and for discovering novel biomarkers. However, the development of integrative approaches to complement gene expression (GE) data with other types of gene information, such as copy number (CN) and chromosomal localization, still represents a computational challenge in the genomic arena. This work presents a computational procedure that directly integrates CN and GE profiles at genome-wide level. When applied to DNA/RNA paired data, this approach leads to the identification of Significant Overlaps of Differentially Expressed and Genomic Imbalanced Regions (SODEGIR). This goal is accomplished in three steps. The first step extends to CN a method for detecting regional imbalances in GE. The second part provides the integration of CN and GE data and identifies chromosomal regions with concordantly altered genomic and transcriptional status in a tumor sample. The last step elevates the single-sample analysis to an entire dataset of tumor specimens. When applied to study chromosomal aberrations in a collection of astrocytoma and renal carcinoma samples, the procedure proved to be effective in identifying discrete chromosomal regions of coordinated CN alterations and changes in transcriptional levels.
Also flagged:mitochondrialneurodegenerative disordersmetabolismcoactivatorsSIRT1deacetylase
Journal Article2009-06-19✓ 1 SnippetWareski P, Vaarmann A, Choubey V, Safiulina D, Liiv J, Kuum M, Kaasik A.
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…Htt…
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Recent studies indicate that regulation of cellular oxidative capacity through enhancing mitochondrial biogenesis may be beneficial for neuronal recovery and survival in human neurodegenerative disorders. The peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1alpha) has been shown to be a master regulator of mitochondrial biogenesis and cellular energy metabolism in muscle and liver. The aim of our study was to establish whether PGC-1alpha and PGC-1beta control mitochondrial density also in neurons and if these coactivators could be up-regulated by deacetylation. The results demonstrate that PGC-1alpha and PGC-1beta control mitochondrial capacity in an additive and independent manner. This effect was observed in all studied subtypes of neurons, in cortical, midbrain, and cerebellar granule neurons. We also observed that endogenous neuronal PGC-1alpha but not PGC-1beta could be activated through its repressor domain by suppressing it. Results demonstrate also that overexpression of SIRT1 deacetylase or suppression of GCN5 acetyltransferase activates transcriptional activity of PGC-1alpha in neurons and increases mitochondrial density. These effects were mediated exclusively via PGC-1alpha, since overexpression of SIRT1 or suppression of GCN5 was ineffective where PGC-1alpha was suppressed by short hairpin RNA. Moreover, the results demonstrate that overexpression of PGC-1beta or PGC-1alpha or activation of the latter by SIRT1 protected neurons from mutant alpha-synuclein- or mutant huntingtin-induced mitochondrial loss. These evidences demonstrate that activation or overexpression of the PGC-1 family of coactivators could be used to compensate for neuronal mitochondrial loss and suggest that therapeutic agents activating PGC-1 would be valuable for treating neurodegenerative diseases in which mitochondrial dysfunction and oxidative damage play an important pathogenic role.
Also flagged:Gene expressioncancermultiple myelomaCTmyelomatumor
Journal Article2009-06-19✓ 1 SnippetCondomines M, Hose D, Rème T, Requirand G, Hundemer M, Schoenhals M, Goldschmidt H, Klein B.
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…ANKRD45…
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Cancer-testis (CT) Ags are attractive targets for immunotherapeutic strategies since they are aberrantly expressed in malignant cells and not, or in limited number, in somatic tissues, except germ cells. To identify novel CT genes in multiple myeloma, we used Affymetrix HG-U133 gene expression profiles of 5 testis, 64 primary multiple myeloma cells (MMC), and 24 normal tissue samples. A 5-filter method was developed to keep known CT genes while deleting non-CT genes. Starting from 44,928 probe sets, including probe sets for 18 previously described CT genes, we have obtained 82 genes expressed in MMC and testis and not detected in more than 6 normal tissue samples. This list includes 14 of the 18 known CT genes and 68 novel putative CT genes. Real-time RT-PCR was performed for 34 genes in 12 normal tissue samples, 5 MMC samples, and one sample of five pooled testes. It has validated the CT status of 23 of 34 genes (67%). We found one novel "testis-restricted" gene (TEX14, expression in testis and tumor only), eight "tissue-restricted" (mRNA detected in one or two nongametogenic tissues), and seven "differentially expressed" (mRNA detected in three to six nongametogenic tissues) CT genes. Further studies are warranted to determine the immunogenicity of these novel CT Ag candidates.
…This observation is of potential interest regarding future targeted therapy, as in such cases interfering with the ability of netrin-1 to inhibit DCC or UNC5H-induced cell death is associated with apoptosis of netrin-1-expressing tumor cells in vitro, and with inhibition of tumor growth or metastasis in different animal tumor models.…
Abstract)
…Taking advantage of this property, we utilized a recombinant specific domain of DCC that (i) interacts with netrin-1 and (ii) inhibits netrin-1-induced multimerization, to trigger apoptosis in netrin-dependent tumor cells.…
Abstract)
…the dependence receptorsDCC(Deleted in colorectal…
Abstract)
…netrin-1 to inhibitDCCor UNC5H-induced cell…
Abstract)
…multimerization of bothDCCand UNC5H2 receptors,…
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Netrin-1 was recently proposed to control tumorigenesis by inhibiting apoptosis induced by the dependence receptors DCC (Deleted in colorectal cancer) and UNC5H. Although the loss of these dependence receptors' expression has been described as a selective advantage for tumor growth and progression in numerous cancers, recent observations have shown that some tumors may use an alternative strategy to block dependence receptor-induced programmed cell death: the autocrine expression of netrin-1. This alternative strategy has been observed in a large fraction of aggressive breast cancers, neuroblastoma, pancreatic adenocarcinoma, and lung cancer. This observation is of potential interest regarding future targeted therapy, as in such cases interfering with the ability of netrin-1 to inhibit DCC or UNC5H-induced cell death is associated with apoptosis of netrin-1-expressing tumor cells in vitro, and with inhibition of tumor growth or metastasis in different animal tumor models. The understanding of the mechanism by which netrin-1 inhibits cell death is therefore of interest. Here, we show that netrin-1 triggers the multimerization of both DCC and UNC5H2 receptors, and that multimerization of the intracellular domain of DCC and UNC5H2 is the critical step to inhibit the proapoptotic effects of both of these receptors. Taking advantage of this property, we utilized a recombinant specific domain of DCC that (i) interacts with netrin-1 and (ii) inhibits netrin-1-induced multimerization, to trigger apoptosis in netrin-dependent tumor cells.
Also flagged:axonalLim-HDLhx2Lhx1axonsaxonal projections
Journal Article2009-06-19✓ 1 SnippetAvraham O, Hadas Y, Vald L, Zisman S, Schejter A, Visel A, Klar A.
In-Text Gene Mentions
Results)
…located between thePou3f2gene and the…
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<h4>Background</h4>Lim-HD proteins control crucial aspects of neuronal differentiation, including subtype identity and axonal guidance. The Lim-HD proteins Lhx2/9 and Lhx1/5 are expressed in the dorsal spinal interneuron populations dI1 and dI2, respectively. While they are not required for cell fate acquisition, their role in patterning the axonal trajectory of dI1 and dI2 neurons remains incompletely understood.<h4>Results</h4>Using newly identified dI1- and dI2-specific enhancers to trace axonal trajectories originating from these interneurons, we found that each population is subdivided into several distinct groups according to their axonal pathways. dI1 neurons project axons rostrally, either ipsi- or contra-laterally, while dI2 are mostly commissural neurons that project their axons rostrally and caudally. The longitudinal axonal tracks of each neuronal population self-fasciculate to form dI1- and dI2-specific bundles. The dI1 bundles are spatially located ventral relative to dI2 bundles. To examine the functional contribution of Lim-HD proteins to establishment of dI axonal projections, the Lim-HD code of dI neurons was altered by cell-specific ectopic expression. Expression of Lhx1 in dI1 neurons caused a repression of Lhx2/9 and imposed caudal projection to the caudal commissural dI1 neurons. Complementarily, when expressed in dI2 neurons, Lhx9 repressed Lhx1/5 and triggered a bias toward rostral projection in otherwise caudally projecting dI2 neurons, and ventral shift of the longitudinal axonal fascicule.<h4>Conclusion</h4>The Lim-HD proteins Lhx9 and Lhx1 serve as a binary switch in controlling the rostral versus caudal longitudinal turning of the caudal commissural axons. Lhx1 determines caudal turning and Lhx9 triggers rostral turning.
Also flagged:Histone H4Antimicrobial peptidespeptidespeptideSEBantibody
Journal Article2009-06-18✓ 1 SnippetLee DY, Huang CM, Nakatsuji T, Thiboutot D, Kang SA, Monestier M, Gallo RL.
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…linker histones…
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Antimicrobial peptides, such as cathelicidin and beta defensins, directly kill microbes and have been detected in human sebaceous glands and cell lines. Despite the presence of several such peptides, the apparent abundance of these is insufficient for direct killing of most skin pathogens. In this study, we sought to determine which molecules provide the majority of antimicrobial peptide activity in human sebocytes. Acid-soluble protein extracts of SEB-1 sebocytes were separated by reverse-phase high-performance liquid chromatography and were assayed for their capacity to inhibit the growth of Staphylococcus aureus. Antimicrobial activity was isolated in a single major fraction and identified to be histone H4 by mass spectrometry and western blot analysis. The importance of histone H4 in the antimicrobial activity of sebocytes was confirmed by a specific neutralizing antibody and by direct demonstration that recombinant histone H4 had antimicrobial activity against S. aureus and Propionibacterium acnes. In addition, histone H4 enhanced the antimicrobial action of free fatty acids in human sebum. Taken together, these results indicate that the release of histone H4 by holocrine secretion from the sebaceous gland may play an important role in innate immunity.
Also flagged:Octreotidehepatocellular carcinomacancerdeathcirrhosischronic infections
Journal Article2009-06-18✓ 1 SnippetGuo TK, Hao XY, Ma B, Yang KH, Li YP, Li HL, Gu YH, Cai H, Liu YL, Li Y, Zhan WP.
In-Text Gene Mentions
Text
…hemochromatosis…
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<h4>Purpose</h4>To evaluate the effectiveness of octreotide in advanced hepatocellular carcinoma participants on the basis of randomized controlled trials.<h4>Methods</h4>We searched the Cochrane Center Register of Controlled Trials in The Cochrane Library, PubMed, EMBASE, Chinese Biomedical Literature Database, China Journal Full-text Database, Chinese Scientific Journals Database up to June 2008 in any language. Randomized controlled trials of octreotide for advanced hepatocellular carcinoma were selected and evaluated by two investigators. Any disagreement was solved by discussion. Analyses were performed using Review Manager 4.2.<h4>Results</h4>Six randomized controlled trials totaling 352 participants were included. The median survival time was reported in four randomized controlled trials. The results between the octreotide group and the control group (the placebo or best supportive care group) were as follows: 13.0 versus 4.0 months, 1.93 versus 1.97 months, 4.7 versus 5.3 months, and 7.0 versus 2.5 months. Three randomized controlled trials reported 6-month survival rates and 12-month survival rates and meta-analysis results in these two outcomes [(RR 1.35, 95% CI 0.92-1.97); (RR 1.35, 95% CI 0.66-11.16) respectively] were not found to be statistically significant by random-effects model. When we analyzed 6-month survival rates by fixed-effect model (RR 1.30, 95% CI 1.02-1.66), meta-analysis result reached statistical significance.<h4>Conclusions</h4>As for the limitations of the included trials, the result may not demonstrate a significant superiority of octreotide administration in participants with advanced hepatocellular carcinoma from the available evidence.
…Afterwards, for the samples at 180 and 360 days of following, a medical safety monitor in the DCC will receive the report directly from the laboratory.…
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<h4>Background</h4>Highly active antiretroviral therapy produces a significant decrease in HIV-1 replication and allows an increase in the CD4 T-cell count, leading to a decrease in the incidence of opportunistic infections and mortality. However, the cost, side effects and complexity of antiretroviral regimens have underscored the immediate need for additional therapeutic approaches. Statins exert pleiotropic effects through a variety of mechanisms, among which there are several immunoregulatory effects, related and unrelated to their cholesterol-lowering activity that can be useful to control HIV-1 infection.<h4>Methods/design</h4>Randomized, double-blinded, placebo controlled, single-center, phase-II clinical trial. One hundred and ten chronically HIV-1-infected patients, older than 18 years and naïve for antiretroviral therapy (i.e., without prior or current management with antiretroviral drugs) will be enrolled at the outpatient services from the most important centres for health insurance care in Medellin-Colombia. The interventions will be lovastatin (40 mg/day, orally, for 12 months; 55 patients) or placebo (55 patients). Our primary aim will be to determine the effect of lovastatin on viral replication. The secondary aim will be to determine the effect of lovastatin on CD4+ T-cell count in peripheral blood. As tertiary aims we will explore differences in CD8+ T-cell count, expression of activation markers (CD38 and HLA-DR) on CD4 and CD8 T cells, cholesterol metabolism, LFA-1/ICAM-1 function, Rho GTPases function and clinical evolution between treated and not treated HIV-1-infected individuals.<h4>Discussion</h4>Preliminary descriptive studies have suggested that statins (lovastatin) may have anti HIV-1 activity and that their administration is safe, with the potential effect of controlling HIV-1 replication in chronically infected individuals who had not received antiretroviral medications. Considering that there is limited clinical data available on this topic, all these findings warrant further evaluation to determine if long-term administration of statins may benefit the virological and immunological evolution in HIV-1-infected individuals before the use of antiretroviral therapy is required.<h4>Trial registration</h4>Registration number NCT00721305.
We present a method for testing overrepresentation of biological pathways, indexed by gene-ontology terms, in lists of significant SNPs from genome-wide association studies. This method corrects for linkage disequilibrium between SNPs, variable gene size, and multiple testing of nonindependent pathways. The method was applied to the Wellcome Trust Case-Control Consortium Crohn disease (CD) data set. At a general level, the biological basis of CD is relatively well known for a complex genetic trait, and it thus acted as a test of the method. The method, known as ALIGATOR (Association LIst Go AnnoTatOR), successfully detected biological pathways implicated in CD. The method was also applied to a meta-analysis of bipolar disorder, and it implicated the modulation of transcription and cellular activity, including that which occurs via hormonal action, as an important player in pathogenesis.
Also flagged:chromatinhistone acetyltransferaseneurologic diseasesDNA methyltransferasetranscription factorCTCF
Journal Article2009-06-18No SnippetsDion V, Wilson JH.
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Trinucleotide repeat expansion underlies at least 17 neurological diseases. In affected individuals, the expanded locus is characterized by dramatic changes in chromatin structure and in repeat tract length. Interestingly, recent studies show that several chromatin modifiers, including a histone acetyltransferase, a DNA methyltransferase and the chromatin insulator CTCF can modulate repeat instability. Here, we propose that the unusual chromatin structure of expanded repeats directly impacts their instability. We discuss several potential models for how this might occur, including a role for DNA repair-dependent epigenetic reprogramming in increasing repeat instability, and the capacity of epigenetic marks to alter sense and antisense transcription, thereby affecting repeat instability.
Anxiety disorders are the most common psychiatric illnesses in the United States with approximately 30% of the population experiencing anxiety-related symptoms in their lifetime [Kessler RC, Berglund P, Demler O, Jin R, Merikangas KR, Walters EE (2005) Lifetime prevalence and age-of-onset distributions of Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) disorders in the National Comorbidity Survey Replication. Arch Gen Psychiatry 62:593-60]. Notably, a variety of studies have demonstrated that 30-40% of the variance contributing to these disorders is heritable. In the present review, we discuss the latest findings regarding the genetic and environmental influences on the development and symptomatology of anxiety disorders. Specific emphasis is placed on posttraumatic stress disorder (PTSD) due to its uniqueness as an anxiety disorder; its diagnosis is dependent on a precipitating traumatic event and its development appears to be mediated by both genetic and environmental contributions. The co-morbidity of anxiety disorders and the potential re-classification of anxiety disorders as part of DSM-V are reviewed given the potential impact on the interpretation and design of genetic investigations. Lastly, several keys to future genetic studies are highlighted. Thorough analyses of the gene by environment (GxE) interactions that govern one's vulnerability to anxiety disorder(s), the effectiveness of individual treatment strategies, and the severity of symptoms may lead to more effective prophylactic (e.g. social support) and treatment strategies.
Also flagged:ataxin-1histidineSpinocerebellar ataxia type 1SCA1polyglutaminenucleus
Journal Article2009-06-18✓ 1 SnippetJayaraman M, Kodali R, Wetzel R.
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…htt…
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Spinocerebellar ataxia type 1 (SCA1) is one of a group of nine expanded CAG repeat diseases, in which polyglutamine (polyQ) expansion above a threshold is associated with increased disease risk and aggregation. SCA1 is unique in which the polyQ in the disease protein, ataxin1, often contains a few His residues that appear to block toxicity. Here, we ask how His insertions affect aggregation by comparing a Q(30) peptide with and without a centrally inserted His-Gln-His sequence. We found that at pH 7.5-8.5, His interruptions decrease polyQ aggregation rates but do not change the spontaneous growth mechanism: nucleated growth polymerization with a critical nucleus of one without non-fibrillar intermediates. The decreased aggregation rates are because of reductions in nucleation equilibrium constants. At pH 6, however, the His-interrupted peptide aggregates by a different mechanism that involves a low ThT-binding intermediate and produces a polymorphic amyloid product. In aggregates grown at pH 7.5, the His residues are solvent-accessible. Aggregates of His-inserted polyQ are good seeds for Q(30) elongation, suggesting the potential to recruit polyQ proteins in the cell. Our data are therefore most consistent with His insertions blocking toxicity by suppressing rates and/or altering pathways of spontaneous aggregation.
Also flagged:ironmetabolismend-stage renal diseaseHepcidin-25C reactive proteinHepcidin
Journal Article2009-06-18✓ 5 SnippetsValenti L, Girelli D, Valenti GF, Castagna A, Como G, Campostrini N, Rametta R, Dongiovanni P, Messa P, Fargion S.
In-Text Gene Mentions
Abstract)
…HFE mutations modulate the effect of iron on serum hepcidin-25 in chronic hemodialysis patients.…
Abstract)
…inflammation, and relatively reduced in subjects carrying frequent HFE…
Title)
…HFEmutations modulate the…
Abstract)
…genetic factors, namelyHFEmutations, has not…
Abstract)
…hepcidin, iron indices,HFEgenotype, and erythropoietic…
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<h4>Background and objectives</h4>Increased serum hepcidin has been reported in patients receiving chronic hemodialysis, and hypothesized to contribute to the alterations of iron metabolism of end-stage renal disease. However, no quantitative assessment is available to date; the clinical determinants are still under definition; and the role of genetic factors, namely HFE mutations, has not yet been evaluated. The aim of this study was to quantitatively assess serum hepcidin-25 in hemodialysis patients versus controls, and analyze the relationship between hepcidin, iron indices, HFE genotype, and erythropoietic parameters.<h4>Design, setting, participants & measurements</h4>Sixty-five hemodialysis patients and 57 healthy controls were considered. Hepcidin-25 was evaluated by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry, HFE genotype by restriction analysis.<h4>Results</h4>Serum hepcidin-25 was higher in hemodialysis patients compared with controls. In patients, hepcidin-25 correlated positively with ferritin and C reactive protein, and negatively with serum iron after adjustment for confounders. Hepcidin/ferritin ratio was lower in patients with (n = 25) than in those without (n = 40) HFE mutations. At multivariate analysis, hepcidin-25 was independently associated with ferritin and HFE status. In a subgroup of 22 "stable" patients, i.e., with Hb levels on target, normal CRP levels, and absence of complications for at least 1 yr, hepcidin-25 was negatively correlated with Hb levels independently of confounders.<h4>Conclusions</h4>Serum hepcidin-25 is increased in hemodialysis patients, regulated by iron stores and inflammation, and relatively reduced in subjects carrying frequent HFE mutations. Hepcidin-25 may contribute to the pathogenesis of anemia by decreasing iron availability.
Alveolar enlargement, which is characteristic of bronchopulmonary dysplasia, congenital matrix disorders, and cigarette smoke-induced emphysema, is thought to result from enhanced inflammation and ensuing excessive matrix proteolysis. Although there is recent evidence that cell death and oxidative stress punctuate these diseases, the mechanistic link between abnormal lung extracellular matrix and alveolar enlargement is lacking. We hypothesized that the tight-skin (TSK) mouse, which harbors a spontaneous internal duplication in the microfibrillar glycoprotein fibrillin-1, might show whether matrix alterations are sufficient to promote oxidative stress and cell death, injury cascades central to the development of clinical emphysema. We observed no evidence of increased metalloprotease activation by histochemical and zymographic methods. We did find initial oxidative stress followed by increased apoptosis in the postnatal TSK lung. Both blunted antioxidant production and reduced extracellular superoxide dismutase activity were evident in the neonatal lung. High-dose antioxidant treatment with N-acetylcysteine improved airspace caliber and attenuated oxidative stress and apoptosis in neonatal and adult TSK mice. These data establish that an abnormal extracellular matrix without overt elastolysis is sufficient to confer susceptibility to postnatal normoxia, reminiscent of bronchopulmonary dysplasia. The resultant oxidative stress and apoptosis culminate in profound airspace enlargement. The TSK lung exemplifies the critical interplay between extracellular matrix, oxidative stress, and cell-death cascades that may contribute to genetic and acquired airspace enlargement.
Also flagged:Rho GTPasesmembraneDynaminGTPaseRhoGEFgrowth cones
Journal Article2009-06-17✓ 1 SnippetXin X, Rabiner CA, Mains RE, Eipper BA.
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Introduction)
…in Colorectal Cancer (DCC) receptor homolog, to…
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<h4>Background</h4>Guanine nucleotide exchange factors (GEFs) and their target Rho GTPases regulate cytoskeletal changes and membrane trafficking. Dynamin, a large force-generating GTPase, plays an essential role in membrane tubulation and fission in cells. Kalirin12, a neuronal RhoGEF, is found in growth cones early in development and in dendritic spines later in development.<h4>Results</h4>The IgFn domain of Kalirin12, not present in other Kalirin isoforms, binds dynamin1 and dynamin2. An inactivating mutation in the GTPase domain of dynamin diminishes this interaction and the isolated GTPase domain of dynamin retains the ability to bind Kalirin12. Co-immunoprecipitation demonstrates an interaction of Kalirin12 and dynamin2 in embryonic brain. Purified recombinant Kalirin-IgFn domain inhibits the ability of purified rat brain dynamin to oligomerize in response to the presence of liposomes containing phosphatidylinositol-4,5-bisphosphate. Consistent with this, expression of exogenous Kalirin12 or its IgFn domain in PC12 cells disrupts clathrin-mediated transferrin endocytosis. Similarly, expression of exogenous Kalirin12 disrupts transferrin endocytosis in cortical neurons. Expression of Kalirin7, a shorter isoform which lacks the IgFn domain, was previously shown to inhibit clathrin-mediated endocytosis; the GTPase domain of dynamin does not interact with Kalirin7.<h4>Conclusion</h4>Kalirin12 may play a role in coordinating Rho GTPase-mediated changes in the actin cytoskeleton with dynamin-mediated changes in membrane trafficking.
…This study investigated the effects of a functional polymorphism in the regulatory region (5-HTTLPR) of the human 5-HT transporter (5-HTT) gene on observational FC, risk taking and susceptibility to framing in decision making under uncertainty, as well as multidimensional anxiety and autonomic control of the heart in healthy volunteers.…
Abstract)
…human 5-HT transporter (5-HTT) gene on observational…
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…5-HTT…
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Serotonin (5-HT) modulates emotional and cognitive functions such as fear conditioning (FC) and decision making. This study investigated the effects of a functional polymorphism in the regulatory region (5-HTTLPR) of the human 5-HT transporter (5-HTT) gene on observational FC, risk taking and susceptibility to framing in decision making under uncertainty, as well as multidimensional anxiety and autonomic control of the heart in healthy volunteers. The present results indicate that in comparison to the homozygotes for the long (l) version of 5-HTTLPR, the carriers of the short (s) version display enhanced observational FC, reduced financial risk taking and increased susceptibility to framing in economic decision making. We also found that s-carriers have increased trait anxiety due to threat in social evaluation, and ambiguous threat perception. In addition, s-carriers also show reduced autonomic control over the heart, and a pattern of reduced vagal tone and increased sympathetic activity in comparison to l-homozygotes. This is the first genetic study that identifies the association of a functional polymorphism in a key neurotransmitter-related gene with complex social-emotional and cognitive processes. The present set of results suggests an endophenotype of anxiety disorders, characterized by enhanced social learning of fear, impaired decision making and dysfunctional autonomic activity.
Also flagged:inflammatory responseGlioblastomabrain tumorsGene expressionangiogenesisBIRC3
Journal Article2009-06-17No SnippetsMurat A, Migliavacca E, Hussain SF, Heimberger AB, Desbaillets I, Hamou MF, Rüegg C, Stupp R, Delorenzi M, Hegi ME.
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Glioblastoma are rapidly proliferating brain tumors in which hypoxia is readily recognizable, as indicated by focal or extensive necrosis and vascular proliferation, two independent diagnostic criteria for glioblastoma. Gene expression profiling of glioblastoma revealed a gene expression signature associated with hypoxia-regulated genes. The correlated gene set emerging from unsupervised analysis comprised known hypoxia-inducible genes involved in angiogenesis and inflammation such as VEGF and BIRC3, respectively. The relationship between hypoxia-modulated angiogenic genes and inflammatory genes was associated with outcome in our cohort of glioblastoma patients treated within prospective clinical trials of combined chemoradiotherapy. The hypoxia regulation of several new genes comprised in this cluster including ZNF395, TNFAIP3, and TREM1 was experimentally confirmed in glioma cell lines and primary monocytes exposed to hypoxia in vitro. Interestingly, the cluster seems to characterize differential response of tumor cells, stromal cells and the macrophage/microglia compartment to hypoxic conditions. Most genes classically associated with the inflammatory compartment are part of the NF-kappaB signaling pathway including TNFAIP3 and BIRC3 that have been shown to be involved in resistance to chemotherapy.Our results associate hypoxia-driven tumor response with inflammation in glioblastoma, hence underlining the importance of tumor-host interaction involving the inflammatory compartment.
…hemochromatosis have a mutation in one of the mentioned HFE…
I A O 0000615)
…HFE mutations, where iron and ferritin values in peripheral blood are relevant screening parameters for hemochromatosis…
I A O 0000613)
…hemochromatosis (HFE…
Abstract)
…Hemochromatosisand porphyria cutanea…
Introduction)
…mutations in thehemochromatosisgene (C282Y and…
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We present a 27-year-old female Caucasian patient, who initially presented with extensive fragility and blistering of mainly the dorsal side of both hands. Histology and urine porphyrin analysis confirmed the diagnosis of porphyria cutanea tarda. Internal screening for underlying disease revealed C282Y mutation-associated primary hemochromatosis, a hereditary iron-overload syndrome that may cause toxicity of a variety of organs. Hemochromatosis and porphyria cutanea tarda are pathogenetically linked as iron interferes with heme synthesis pathway. Patient was successfully treated with phlebotomy and low-dose hydroxychloroquine.
Journal Article2009-06-16✓ 5 SnippetsMuccioli GG, Sia A, Muchowski PJ, Stella N.
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Methods)
…Htt103Q is a galactose (GAL)-inducible, FLAG- and GFP-tagged construct encoding the first 17 amino acids of Htt fused to a polyQ tract of 103 glutamines, longer than the threshold for Huntington disease pathogenesis.…
Methods)
…amino acids ofHttfused to a…
Results)
…expressed mutant huntingtin (Htt) fragments and α-synuclein…
Results)
…Httfragments containing 25…
Results)
…Spo14, we expressedHttfragments and α-synuclein…
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<h4>Background</h4>Lipids can act as signaling molecules, activating intracellular and membrane-associated receptors to regulate physiological functions. To understand how a newly discovered signaling lipid functions, it is necessary to identify and characterize the enzymes involved in their production and inactivation. The signaling lipid N-palmitoylethanolamine (PEA) is known to activate intracellular and membrane-associated receptors and regulate physiological functions, but little is known about the enzymes involved in its production and inactivation.<h4>Principal findings</h4>Here we show that Saccharomyces cerevisiae produce and inactivate PEA, suggesting that genetic manipulations of this lower eukaryote may be used to identify the enzymes involved in PEA metabolism. Accordingly, using single gene deletion mutants, we identified yeast genes that control PEA metabolism, including SPO14 (a yeast homologue of the mammalian phospholipase D) that controls PEA production and YJU3 (a yeast homologue of the mammalian monoacylglycerol lipase) that controls PEA inactivation. We also found that PEA metabolism is affected by heterologous expression of two mammalian proteins involved in neurodegenerative diseases, namely huntingtin and alpha-synuclein.<h4>Significance</h4>Together these findings show that forward and reverse genetics in S. cerevisiae can be used to identify proteins involved in PEA production and inactivation, and suggest that mutated proteins causing neurodegenerative diseases might affect the metabolism of this important signaling lipid.
Also flagged:MybTRF2doctelomere-bindingchromatinsec
Journal Article2009-06-16✓ 1 SnippetBaker AM, Fu Q, Hayward W, Lindsay SM, Fletcher TM.
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Discussion)
…26 ) orlinker histoneshistones ( 29…
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Eukaryotic DNA is packaged into chromatin, which regulates genome activities such as telomere maintenance. This study focuses on the interactions of a myb/SANT DNA-binding domain from the telomere-binding protein, TRF2, with reconstituted telomeric nucleosomal array fibers. Biophysical characteristics of the factor-bound nucleosomal arrays were determined by analytical agarose gel electrophoresis (AAGE) and single molecules were visualized by atomic force microscopy (AFM). The TRF2 DNA-binding domain (TRF2 DBD) neutralized more negative charge on the surface of nucleosomal arrays than histone-free DNA. Binding of TRF2 DBD at lower concentrations increased the radius and conformational flexibility, suggesting a distortion of the fiber structure. Additional loading of TRF2 DBD onto the nucleosomal arrays reduced the flexibility and strongly blocked access of micrococcal nuclease as contour lengths shortened, consistent with formation of a unique, more compact higher-order structure. Mirroring the structural results, TRF2 DBD stimulated a strand invasion-like reaction, associated with telomeric t-loops, at lower concentrations while inhibiting the reaction at higher concentrations. Full-length TRF2 was even more effective at stimulating this reaction. The TRF2 DBD had less effect on histone-free DNA structure and did not stimulate the t-loop reaction with this substrate, highlighting the influence of chromatin structure on the activities of DNA-binding proteins.
Journal Article2009-06-16✓ 1 SnippetTuri A, Loglisci C, Salvemini E, Grillo G, Malerba D, D'Elia D.
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Results)
…dosage compensation complex (DCC) and the subsequent…
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<h4>Background</h4>Many studies report about detection and functional characterization of cis-regulatory motifs in untranslated regions (UTRs) of mRNAs but little is known about the nature and functional role of their distribution. To address this issue we have developed a computational approach based on the use of data mining techniques. The idea is that of mining frequent combinations of translation regulatory motifs, since their significant co-occurrences could reveal functional relationships important for the post-transcriptional control of gene expression. The experimentation has been focused on targeted mitochondrial transcripts to elucidate the role of translational control in mitochondrial biogenesis and function.<h4>Results</h4>The analysis is based on a two-stepped procedure using a sequential pattern mining algorithm. The first step searches for frequent patterns (FPs) of motifs without taking into account their spatial displacement. In the second step, frequent sequential patterns (FSPs) of spaced motifs are generated by taking into account the conservation of spacers between each ordered pair of co-occurring motifs. The algorithm makes no assumption on the relation among motifs and on the number of motifs involved in a pattern. Different FSPs can be found depending on different combinations of two parameters, i.e. the threshold of the minimum percentage of sequences supporting the pattern, and the granularity of spacer discretization. Results can be retrieved at the UTRminer web site: http://utrminer.ba.itb.cnr.it/. The discovered FPs of motifs amount to 216 in the overall dataset and to 140 in the human subset. For each FP, the system provides information on the discovered FSPs, if any. A variety of search options help users in browsing the web resource. The list of sequence IDs supporting each pattern can be used for the retrieval of information from the UTRminer database.<h4>Conclusion</h4>Computational prediction of structural properties of regulatory sequences is not trivial. The presented data mining approach is able to overcome some limits observed in other competitive tools. Preliminary results on UTR sequences from nuclear transcripts targeting mitochondria are promising and lead us to be confident on the effectiveness of the approach for future developments.
Also flagged:motility disorderscell cycleaxonneuronal differentiationtranscription factorsPhox2b
Journal Article2009-06-16No SnippetsHao MM, Young HM.
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The mature enteric nervous system (ENS) is composed of many different neuron subtypes and enteric glia, which all arise from the neural crest. How this diversity is generated from neural crest-derived cells is a central question in neurogastroenterology, as defects in these processes are likely to underlie some paediatric motility disorders. Here we review the developmental appearance (the earliest age at which expression of specific markers can be localized) and birthdates (the age at which precursors exit the cell cycle) of different enteric neuron subtypes, and their projections to some targets. We then focus on what is known about the mechanisms underlying the generation of enteric neuron diversity and axon pathfinding. Finally, we review the development of the ENS in humans and the etiologies of a number of paediatric motility disorders.
Also flagged:autismgenetic syndromesgene expressionsubstance abuseTourette syndromedementias
Journal Article2009-06-16✓ 2 SnippetsLewis M, Kim SJ.
In-Text Gene Mentions
S I O 001029)
…Although association studies involving the functional insertion/deletion polymorphism in the promoter (5-HTTLPR) and a polymorphism in intron 2 have been inconclusive (possibly due to phenotypic heterogeneity), several groups identified evidence for genetic linkage of autism to the chromosome 17q11.2 region that harbors the 5-HTT locus (SLC6A4) [88, 114–116].…
S I O 001029)
…The serotonin transporter (5-HTT) has been considered a strong candidate gene for autism based on reports of hyperserotonemia and the efficacy of selective 5-HT reuptake inhibitors (SSRIs) in treating repetitive behaviors.…
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Restricted, repetitive behaviors (RRBs) are heterogeneous ranging from stereotypic body movements to rituals to restricted interests. RRBs are most strongly associated with autism but occur in a number of other clinical disorders as well as in typical development. There does not seem to be a category of RRB that is unique or specific to autism and RRB does not seem to be robustly correlated with specific cognitive, sensory or motor abnormalities in autism. Despite its clinical significance, little is known about the pathophysiology of RRB. Both clinical and animal models studies link repetitive behaviors to genetic mutations and a number of specific genetic syndromes have RRBs as part of the clinical phenotype. Genetic risk factors may interact with experiential factors resulting in the extremes in repetitive behavior phenotypic expression that characterize autism. Few studies of individuals with autism have correlated MRI findings and RRBs and no attempt has been made to associate RRB and post-mortem tissue findings. Available clinical and animal models data indicate functional and structural alterations in cortical-basal ganglia circuitry in the expression of RRB, however. Our own studies point to reduced activity of the indirect basal ganglia pathway being associated with high levels of repetitive behavior in an animal model. These findings, if generalizable, suggest specific therapeutic targets. These, and perhaps other, perturbations to cortical basal ganglia circuitry are mediated by specific molecular mechanisms (e.g., altered gene expression) that result in long-term, experience-dependent neuroadaptations that initiate and maintain repetitive behavior. A great deal more research is needed to uncover such mechanisms. Work in areas such as substance abuse, OCD, Tourette syndrome, Parkinson's disease, and dementias promise to provide findings critical for identifying neurobiological mechanisms relevant to RRB in autism. Moreover, basic research in areas such as birdsong, habit formation, and procedural learning may provide additional, much needed clues. Understanding the pathophysioloy of repetitive behavior will be critical to identifying novel therapeutic targets and strategies for individuals with autism.
Butyrophilin 1A1 (BTN1A1) and xanthine oxidoreductase (XOR) are highly expressed in the lactating mammary gland and are secreted into milk associated with the milk fat globule membrane (MFGM). Ablation of the genes encoding either protein causes severe defects in the secretion of milk lipid droplets, suggesting that the two proteins may function in the same pathway. Therefore, we determined whether BTN1A1 and XOR directly interact using protein binding assays, surface plasmon resonance analysis, and gel filtration. Bovine XOR bound with high affinity in a pH- and salt-sensitive manner (KD=101+/-31 nM in 10 mM HEPES, 150 mM NaCl, pH 7.4) to the PRY/SPRY/B30.2 domain in the cytoplasmic region of bovine BTN1A1. Binding was stoichiometric, with one XOR dimer binding to either two BTN1A1 monomers or one dimer. XOR bound to BTN1A1 orthologs from mice, humans, or cows but not to the cytoplasmic domains of the closely related human paralogs, BTN2A1 or BTN3A1, or to the B30.2 domain of human RoRet (TRIM 38), a protein in the TRIM family. Analysis of the protein composition of the MFGM of wild type and BTN1A1 null mice showed that most of the XOR in mice lacking BTN1A1 was released from the MFGM in a soluble form when the milk lipid droplets were disrupted to prepare membrane, compared with wild-type mice, in which most of the XOR remained membrane-bound. Thus BTN1A1 functions in vivo to stabilize the association of XOR with the MFGM by direct interactions through the PRY/SPRY/B30.2 domain. The potential significance of BTN1A1/XOR interactions in the mammary gland and other tissues is discussed.
Also flagged:Gliomatosis cerebri typegliomatosis cerebri Type IIgliomatosis cerebri IIangiogenesisVCAM1VEGF
Journal Article2009-06-15✓ 5 SnippetsD'Urso PI, D'Urso OF, Marsigliante S, Storelli C, Distante A, Sanguedolce F, Cimmino A, Luzi G, Gianfreda CD, Montinaro A, Ciappetta P.
In-Text Gene Mentions
I A O 0000613)
…DCC was found methylated in both tumors, MGMT methylated only in Patient 1, in line with the chemotherapy response, and p16 methylated only in Patient 2 since this gene is under-expressed even if not mutated (Figure 4a).…
Discussion)
…The absence of DCC function, associated with several types of tumors, appeared to also affect our patients.…
Discussion)
…The absence ofDCCfunction, associated with…
I A O 0000613)
…in colorectal cancer (DCC) and death-associated protein…
I A O 0000613)
…, DAP3 andDCCin line with…
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<h4>Introduction</h4>TWO TYPES OF GLIOMATOSIS CEREBRI EXIST: Type I and Type II. We report the results of a histological and genetic study of two cases of gliomatosis cerebri Type II, correlating these results with therapy and prognosis.<h4>Case presentation</h4>Two patients, a 52-year-old man (Patient 1) and a 76-year-old man (Patient 2) with gliomatosis cerebri II were admitted to our institution; they underwent surgical treatment and received radiotherapy and chemotherapy. At the 24-month follow-up, Patient 1 was still alive, while Patient 2 had died. The poor prognosis of Patient 2 was underlined by molecular analysis which showed that the angiogenesis related genes VCAM1 and VEGF were overexpressed, reflecting the high degree of neovascularization.<h4>Conclusion</h4>Genes involved in drug resistance and metallothioneins were highly expressed in Patient 2 and this, associated with unmethylated O6-methylguanine methyltransferase, can explain the lack of response to chemotherapy.
Also flagged:axonalmicrotubulesJNK3FATHuntingtinKinesin
Journal Article2009-06-14✓ 5 SnippetsMorfini GA, You YM, Pollema SL, Kaminska A, Liu K, Yoshioka K, Björkblom B, Coffey ET, Bagnato C, Han D, Huang CF, Banker G, Pigino G, Brady ST.
In-Text Gene Mentions
Abstract)
…These data identify JNK3 as a critical mediator of polyQ-Htt toxicity and provide a molecular basis for polyQ-Htt-induced inhibition of FAT.…
Abstract)
…Additional experiments indicated that the effects of polyQ-Htt on FAT were mediated by neuron-specific JNK3 and not by ubiquitously expressed JNK1, providing a molecular basis for neuron-specific pathology in Huntington's disease.…
Discussion)
…Significantly, JNK3, and not JNK1, activity mediated polyQ-Htt effects on FAT, providing a partial explanation for selective neuronal vulnerability in HD.…
Abstract)
…Additional experiments indicate that polyQ-Htt effects on FAT are mediated by the neuron-specific JNK3, and not ubiquitously expressed JNK1, providing a molecular basis for neuron-specific pathology in HD.…
Selected vulnerability of neurons in Huntington's disease suggests that alterations occur in a cellular process that is particularly critical for neuronal function. Supporting this idea, pathogenic Htt (polyQ-Htt) inhibits fast axonal transport (FAT) in various cellular and animal models of Huntington's disease (mouse and squid), but the molecular basis of this effect remains unknown. We found that polyQ-Htt inhibited FAT through a mechanism involving activation of axonal cJun N-terminal kinase (JNK). Accordingly, we observed increased activation of JNK in vivo in cellular and mouse models of Huntington's disease. Additional experiments indicated that the effects of polyQ-Htt on FAT were mediated by neuron-specific JNK3 and not by ubiquitously expressed JNK1, providing a molecular basis for neuron-specific pathology in Huntington's disease. Mass spectrometry identified a residue in the kinesin-1 motor domain that was phosphorylated by JNK3 and this modification reduced kinesin-1 binding to microtubules. These data identify JNK3 as a critical mediator of polyQ-Htt toxicity and provide a molecular basis for polyQ-Htt-induced inhibition of FAT.
Also flagged:nerve growth factormorphogenesiscell differentiationPAIRBP1translationally controlled tumor proteinantibody
Journal Article2009-06-13No SnippetsKobayashi D, Kumagai J, Morikawa T, Wilson-Morifuji M, Wilson A, Irie A, Araki N.
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MS-based quantitative proteomics is widely used for large scale identification of proteins. However, an integrated approach that offers comprehensive proteome coverage, a tool for the quick categorization of the identified proteins, and a standardized biological study method is needed for helping the researcher focus on investigating the proteins with biologically important functions. In this study, we utilized isobaric tagging for relative and absolute quantification (iTRAQ)-based quantitative differential LC/MS/MS, functional annotation with a proprietary gene ontology tool (Molecular Annotation by Gene Ontology (MANGO)), and standard biochemical methods to identify proteins related to neuronal differentiation in nerve growth factor-treated rat pheochromocytoma (PC12) cells, which serve as a representative model system for studying neuronal biological processes. We performed MS analysis by using both nano-LC-MALDI-MS/MS and nano-LC-ESI-MS/MS for maximal proteome coverage. Of 1,482 non-redundant proteins semiquantitatively identified, 72 were differentially expressed with 39 up- and 33 down-regulated, including 64 novel nerve growth factor-responsive PC12 proteins. Gene ontology analysis of the differentially expressed proteins by MANGO indicated with statistical significance that the up-regulated proteins were mostly related to the biological processes of cell morphogenesis, apoptosis/survival, and cell differentiation. Some of the up-regulated proteins of unknown function, such as PAIRBP1, translationally controlled tumor protein, prothymosin alpha, and MAGED1, were further analyzed to validate their significant functions in neuronal differentiation by immunoblotting and immunocytochemistry using each antibody combined with a specific short interfering RNA technique. Knockdown of these proteins caused abnormal cell morphological changes, inhibition of neurite formation, and cell death during each course of the differentiation, confirming their important roles in neurite formation and survival of PC12 cells. These results show that our iTRAQ-MANGO-biological analysis framework, which integrates a number of standard proteomics strategies, is effective for targeting and elucidating the functions of proteins involved in the cellular biological process being studied.
Also flagged:type 2 diabetesobesityTCF7L2genetic diseasePPARGKCNJ11
Journal Article2009-06-13✓ 3 SnippetsSoutham L, Soranzo N, Montgomery SB, Frayling TM, McCarthy MI, Barroso I, Zeggini E.
In-Text Gene Mentions
Methods)
…This criterion yields 17 loci for type 2 diabetes (in or near the TCF7L2, PPARG, KCNJ11, CDKAL1, SLC30A8, IGF2BP2, NOTCH2, THADA, JAZF1, CDC123/CAMK1D, TSPAN8/LGR5, HHEX/IDE, CDKN2A/B, ADAMTS9, TCF2, WFS1 and KCNQ1 genes) [2] and 13 for obesity (associations with BMI) (in or near the FTO, TMEM18, MC4R, GNPDA2, SH2B1, KCTD15, MTCH2, NEGR1, PCSK1, LGR4/LIN7C/BDNF [two independent single nucleotide polymorphisms {SNPs}], ETV5/SFRS10/DGKG and MAF genes) [3–8] (Tables 1 and 2).…
Results)
…Similarly, we did not observe a significant overrepresentation of derived status for the obesity-risk alleles (seven [MC4R, GNPDA2, MTCH2, NEGR1, PCSK1, LGR4/LIN7C/BDNF and ETV5/SFRS10/DGKG], p = 0.50) (Table 2).…
Methods)
…, MTCH2 ,NEGR1, PCSK1 ,…
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<h4>Aims/hypothesis</h4>According to the thrifty genotype hypothesis, the high prevalence of type 2 diabetes and obesity is a consequence of genetic variants that have undergone positive selection during historical periods of erratic food supply. The recent expansion in the number of validated type 2 diabetes- and obesity-susceptibility loci, coupled with access to empirical data, enables us to look for evidence in support (or otherwise) of the thrifty genotype hypothesis using proven loci.<h4>Methods</h4>We employed a range of tests to obtain complementary views of the evidence for selection: we determined whether the risk allele at associated 'index' single-nucleotide polymorphisms is derived or ancestral, calculated the integrated haplotype score (iHS) and assessed the population differentiation statistic fixation index (F (ST)) for 17 type 2 diabetes and 13 obesity loci.<h4>Results</h4>We found no evidence for significant differences for the derived/ancestral allele test. None of the studied loci showed strong evidence for selection based on the iHS score. We find a high F (ST) for rs7901695 at TCF7L2, the largest type 2 diabetes effect size found to date.<h4>Conclusions/interpretation</h4>Our results provide some evidence for selection at specific loci, but there are no consistent patterns of selection that provide conclusive confirmation of the thrifty genotype hypothesis. Discovery of more signals and more causal variants for type 2 diabetes and obesity is likely to allow more detailed examination of these issues.
Also flagged:SOX5transcription factorcell fatechondrocyte differentiationextracellularcollagen
Journal Article2009-06-12✓ 4 SnippetsWright D, Boije H, Meadows JR, Bed'hom B, Gourichon D, Vieaud A, Tixier-Boichard M, Rubin CJ, Imsland F, Hallböök F, Andersson L.
In-Text Gene Mentions
Results)
…Mouse SOX5/SOX6 double knockouts die in utero with severe skeletal dysplasia, demonstrating that these two genes have critical, redundant roles during development [13],[14].…
Results)
…Mouse SOX5/SOX6double knockouts die…
Discussion)
…genes, along withSOX6and SOX13 .…
Discussion)
…formation SOX5 andSOX6assist SOX9 to…
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Pea-comb is a dominant mutation in chickens that drastically reduces the size of the comb and wattles. It is an adaptive trait in cold climates as it reduces heat loss and makes the chicken less susceptible to frost lesions. Here we report that Pea-comb is caused by a massive amplification of a duplicated sequence located near evolutionary conserved non-coding sequences in intron 1 of the gene encoding the SOX5 transcription factor. This must be the causative mutation since all other polymorphisms associated with the Pea-comb allele were excluded by genetic analysis. SOX5 controls cell fate and differentiation and is essential for skeletal development, chondrocyte differentiation, and extracellular matrix production. Immunostaining in early embryos demonstrated that Pea-comb is associated with ectopic expression of SOX5 in mesenchymal cells located just beneath the surface ectoderm where the comb and wattles will subsequently develop. The results imply that the duplication expansion interferes with the regulation of SOX5 expression during the differentiation of cells crucial for the development of comb and wattles. The study provides novel insight into the nature of mutations that contribute to phenotypic evolution and is the first description of a spontaneous and fully viable mutation in this developmentally important gene.
<h4>Background</h4>Protein covalent binding by reactive metabolites of drugs, chemicals and natural products can lead to acute cytotoxicity. Recent rapid progress in reactive metabolite target protein identification has shown that adduction is surprisingly selective and inspired the hope that analysis of target proteins might reveal protein factors that differentiate target- vs. non-target proteins and illuminate mechanisms connecting covalent binding to cytotoxicity.<h4>Results</h4>Sorting 171 known reactive metabolite target proteins revealed a number of GO categories and KEGG pathways to be significantly enriched in targets, but in most cases the classes were too large, and the "percent coverage" too small, to allow meaningful conclusions about mechanisms of toxicity. However, a similar analysis of the directlyinteracting partners of 28 common targets of multiple reactive metabolites revealed highly significant enrichments in terms likely to be highly relevant to cytotoxicity (e.g., MAP kinase pathways, apoptosis, response to unfolded protein). Machine learning was used to rank the contribution of 211 computed protein features to determining protein susceptibility to adduction. Protein lysine (but not cysteine) content and protein instability index (i.e., rate of turnover in vivo) were among the features most important to determining susceptibility.<h4>Conclusion</h4>As yet there is no good explanation for why some low-abundance proteins become heavily adducted while some abundant proteins become only lightly adducted in vivo. Analyzing the directly interacting partners of target proteins appears to yield greater insight into mechanisms of toxicity than analyzing target proteins per se. The insights provided can readily be formulated as hypotheses to test in future experimental studies.
Also flagged:response to oxidative stress8-oxoG DNA glycosylasemitochondrialaconitasecaspase-9mitochondrial aconitase
Journal Article2009-06-12✓ 1 SnippetPanduri V, Liu G, Surapureddi S, Kondapalli J, Soberanes S, de Souza-Pinto NC, Bohr VA, Budinger GR, Schumacker PT, Weitzman SA, Kamp DW.
In-Text Gene Mentions
Text
…hemochromatosis…
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8-Oxoguanine DNA glycosylase (Ogg1) repairs 8-oxo-7,8-dihydroxyguanine (8-oxoG), one of the most abundant DNA adducts caused by oxidative stress. In the mitochondria, Ogg1 is thought to prevent activation of the intrinsic apoptotic pathway in response to oxidative stress by augmenting DNA repair. However, the predominance of the beta-Ogg1 isoform, which lacks 8-oxoG DNA glycosylase activity, suggests that mitochondrial Ogg1 functions in a role independent of DNA repair. We report here that overexpression of mitochondria-targeted human alpha-hOgg1 (mt-hOgg1) in human lung adenocarcinoma cells with some alveolar epithelial cell characteristics (A549 cells) prevents oxidant-induced mitochondrial dysfunction and apoptosis by preserving mitochondrial aconitase. Importantly, mitochondrial alpha-hOgg1 mutants lacking 8-oxoG DNA repair activity were as effective as wild-type mt-hOgg1 in preventing oxidant-induced caspase-9 activation, reductions in mitochondrial aconitase, and apoptosis, suggesting that the protective effects of mt-hOgg1 occur independent of DNA repair. Notably, wild-type and mutant mt-hOgg1 coprecipitate with mitochondrial aconitase. Furthermore, overexpression of mitochondrial aconitase abolishes oxidant-induced apoptosis whereas hOgg1 silencing using shRNA reduces mitochondrial aconitase and augments apoptosis. These findings suggest a novel mechanism that mt-hOgg1 acts as a mitochondrial aconitase chaperone protein to prevent oxidant-mediated mitochondrial dysfunction and apoptosis that might be important in the molecular events underlying oxidant-induced toxicity.
Also flagged:DNA endonucleaserenal diseasespolymeraseSURVEYOR Nucleaseglomerulopathiessteroid
Journal Article2009-06-12No SnippetsVoskarides K, Deltas C.
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SURVEYOR is a new mismatch-specific plant DNA endonuclease that is very efficient for mutation scanning in heteroduplex DNA. It is much faster, cheaper, more sensitive, and easier to perform than other "traditional" mutation detection methods such as single-strand conformation polymorphism analysis, denaturing high-performance liquid chromatography, heteroduplex analysis, and phage resolvases. This is the first comprehensive report on the use of SURVEYOR for screening genes implicated in a spectrum of inherited renal diseases. Of the 48.2 kb screened, 44 variations were identified, accounting for one variation per 1.1 kb. The re-sequencing of multiple samples did not reveal any variation that had not been identified by SURVEYOR, attesting to its high fidelity. Additionally, we tested this enzyme against 15 known variants, 14 of which it identified, thus showing a sensitivity of 93%. We showed that the genetic heterogeneity of renal diseases can be easily overcome using this enzyme with a high degree of confidence and no bias for any specific variations. We also showed for the first time that SURVEYOR does not demonstrate any preference regarding mismatch cleavage at specific positions. Disadvantages of using SURVEYOR include enhanced exonucleolytic activity for some polymerase chain reaction products and less than 100% sensitivity. We report that SURVEYOR can be used as a mutation detection method with a high degree of confidence, offering an excellent alternative for low-budget laboratories and for the rapid manipulation of multiple genes.
…To date, genetic variation in voltage-dependent Ca2+ channels (CACNA1E) and KATP (KCNJ11) channels have been shown to influence insulin secretion and type 2 diabetes risk [8], [9], and genome-wide association studies (GWAS) for type 2 diabetes in Caucasians have proven the importance of genes coding for proteins involved in insulin secretion [10]–[14].…
Introduction)
…2+ channels (CACNA1E) and K…
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<h4>Background</h4>Polymorphisms in the potassium channel, voltage-gated, KQT-like subfamily, member 1 (KCNQ1) have recently been reported to associate with type 2 diabetes. The primary aim of the present study was to investigate the putative impact of these KCNQ1 polymorphisms (rs2283228, rs2237892, rs2237895, and rs2237897) on estimates of glucose stimulated insulin release.<h4>Methodology/principal findings</h4>Genotypes were examined for associations with serum insulin levels following an oral glucose tolerance test (OGTT) in a population-based sample of 6,039 middle-aged and treatment-naïve individuals. Insulin release indices estimated from the OGTT and the interplay between insulin sensitivity and insulin release were investigated using linear regression and Hotelling T2 analyses. Applying an additive genetic model the minor C-allele of rs2237895 was associated with reduced serum insulin levels 30 min (mean+/-SD: (CC) 277+/-160 vs. (AC) 280+/-164 vs. (AA) 299+/-200 pmol/l, p = 0.008) after an oral glucose load, insulinogenic index (29.6+/-17.4 vs. 30.2+/-18.7vs. 32.2+/-22.1, p = 0.007), incremental area under the insulin curve (20,477+/-12,491 vs. 20,503+/-12,386 vs. 21,810+/-14,685, p = 0.02) among the 4,568 individuals who were glucose tolerant. Adjustment for the degree of insulin sensitivity had no effect on the measures of reduced insulin release. The rs2237895 genotype had a similar impact in the total sample of treatment-naïve individuals. No association with measures of insulin release were identified for the less common diabetes risk alleles of rs2237892, rs2237897, or rs2283228.<h4>Conclusion</h4>The minor C-allele of rs2237895 of KCNQ1, which has a prevalence of about 42% among Caucasians was associated with reduced measures of insulin release following an oral glucose load suggesting that the increased risk of type 2 diabetes, previously reported for this variant, likely is mediated through an impaired beta cell function.
…Opposing Role ofCondensinand Radiation-sensitive Gene…
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…Condensin…
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Blocking target of rapamycin signaling by starvation or rapamycin inhibits ribosomal DNA (rDNA) transcription and causes condensin-mediated rDNA condensation and nucleolar contraction. In the absence of condensin, however, repression of rDNA transcription leads to rDNA instability and elevated level of extrachromosomal rDNA circles and nucleolar fragmentation. Here, we show that mutations in the Rad52 homologous recombination machinery block rDNA instability. Rad52 is normally excluded from the nucleolus. In the absence of condensin, however, repression of rDNA transcription results in Rad52 localization to the nucleolus, association with rDNA and subsequent formation of extrachromosomal rDNA circles, and reduced cell survival. In contrast, deletion of RAD52 restores cell viability under the same conditions. These results reveal an opposing role of condensin and Rad52 in the control of rDNA stability under nutrient starvation conditions.
Also flagged:Keap1chronic obstructive pulmonary diseaseCOPDNrf2detoxificationglutathione
Journal Article2009-06-11No SnippetsBlake DJ, Singh A, Kombairaju P, Malhotra D, Mariani TJ, Tuder RM, Gabrielson E, Biswal S.
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Exposure to cigarette smoke (CS) is the primary factor associated with the development of chronic obstructive pulmonary disease (COPD). CS increases the level of oxidants in the lungs, resulting in a depletion of antioxidants, which promotes oxidative stress and the destruction of alveolar tissue. In response to CS, pulmonary epithelial cells counteract increased levels of oxidants by activating Nrf2-dependent pathways to augment the expression of detoxification and antioxidant enzymes, thereby protecting the lung from injury. We hypothesize that increasing the pathways activated by Nrf2 will afford protection against CS-induced lung damage. To this end we have developed a novel mouse model in which the cytosolic inhibitor of Nrf2, Keap1, is genetically deleted in Clara cells, which predominate in the upper airways in mice. Deletion of Keap1 in Clara cells resulted in increased expression of Nrf2-dependent genes, such as Nqo1 and Gclm, as determined by microarray analysis and quantitative PCR. Deletion of Keap1 in airway epithelium decreased Keap1 protein levels and significantly increased the total level of glutathione in the lungs. Increased Nrf2 activation protected Clara cells against oxidative stress ex vivo and attenuated oxidative stress and CS-induced inflammation in vivo. Expression of KEAP1 was also decreased in human epithelial cells through siRNA transfection, which increased the expression of Nrf2-dependent genes and attenuated oxidative stress. In conclusion, activating Nrf2 pathways in tissue-specific Keap1 knockout mice represents an important genetic approach against oxidant-induced lung damage.
Also flagged:ubiquitinFBG2F-BOXgastric cancercell cyclecell cycles
Journal Article2009-06-10No SnippetsZhang L, Hou Y, Wang M, Wu B, Li N.
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<h4>Background</h4>FBG2 (F-BOX6) gene is an important member in ubiquitin metabolic system F-BOX family, and forms E3 complex with the other members in the family. But its role in gastric cancer is still not clear. In the present study, we intended to investigate the influence of FBG2 on the growth, proliferation, apoptosis, invasion and cell cycle of the gastric cancer line MKN45 and gastric cell line HFE145.<h4>Methods</h4>As a critical component of ubiquitin-protein ligase complex, FBG2 cDNA was subcloned into a constitutive vector PCDNA3.1 followed by transfection in MKN45 and HFE145 by using liposome. Then stable transfectants were selected and appraised. The apoptosis and cell cycles of these clones were analyzed by using flow cytometry. The growth and proliferation were analyzed by cell growth curves and colony-forming assay respectively. The invasion of these clones was tested by using cancer cell migration assay. The FBG2 stable expression clones(MKN-FBG2 and HFE-FBG2) and their control groups were detected and compared respectively.<h4>Results</h4>MKN-FBG2 grew faster than MKN45 and MKN-PC(MKN45 transfected with PCDNA3.1 vector). HFE-FBG2 grew faster than HFE145 and HFE-PC(HFE145 transfected with PCDNA3.1 vector). The cell counts of MKN-FBG2 in the forth, fifth, sixth and seventh days were significantly more than those of others (P < 0.05). Cell cycle analysis showed that MKN-FBG2 and HFE-FBG2 proliferated faster, proportions of cells in G2-M and S were different significantly with control groups (P < 0.05). Results of colony-forming assay showed that the colony formation rates of MKN-FBG2 and HFE-FBG2 were higher than those of control groups (P < 0.05). The results of cell migration assay were all negative.<h4>Conclusion</h4>FBG2 can promote the growth and proliferation of gastric cancer cells and normal gastric cells. It can help tumor cell maintain malignant phenotype too. But it can have a negative influence on the apoptosis or the ability of invasion of gastric cancer cells.
<h4>Background</h4>Placental mRNA was detected in maternal whole blood, raising the possibility of using maternal blood for noninvasive prenatal diagnosis. We investigated fetal mRNA detection in maternal whole blood and determined if it offered advantages over maternal plasma analysis.<h4>Methodology</h4>The concentrations of placental expressed genes, CSH1, KISS1, PLAC4 and PLAC1 in plasma and whole blood from healthy pregnant and non-pregnant individuals were compared by real-time quantitative reverse-transcriptase polymerase chain reaction analysis. Their fetal specificity was investigated by comparing the transcript concentrations in pre- and post-delivery samples and through SNP genotyping by matrix-assisted laser-desorption and ionization time-of-flight mass spectrometry. The gene expression profiles of pregnant and non-pregnant whole blood were investigated by microarray analysis. Upregulated genes in pregnant whole blood were selected for further quantitative analysis.<h4>Principal findings</h4>The concentrations of the four transcripts were significantly higher in third trimester maternal whole blood than corresponding plasma without significant correlations. KISS1, PLAC4 and PLAC1 were detected in non-pregnant whole blood but not plasma. The transcripts remained detectable in some postpartum whole blood samples. The PLAC4 mRNA in maternal plasma showed fetal genotype while that in corresponding whole blood indicated both fetal and maternal contributions. Microarray analysis revealed upregulation of genes involved in neutrophil functions in pregnant whole blood including DEFA4, CEACAM8, OLFM4, ORM1, MMP8 and MPO. Though possibly pregnancy-related, they were not pregnancy-specific as suggested by the lack of post-delivery reduction in concentrations.<h4>Conclusions</h4>Maternal plasma is preferred over maternal whole blood for placenta-derived fetal RNA detection. Most studied 'placental' mRNA molecules in maternal whole blood were of maternal origin and might be derived from processes such as 'illegitimate transcription'.
Also flagged:NAFLDhepatic fibrosisnonalcoholic fatty liver diseaseaspartatealanine aminotransferaseCirrhosis
Journal Article2009-06-10✓ 1 SnippetShah AG, Lydecker A, Murray K, Tetri BN, Contos MJ, Sanyal AJ, Nash Clinical Research Network.
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…hemochromatosis…
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<h4>Background & aims</h4>There is a need for a reliable and inexpensive noninvasive marker of hepatic fibrosis in patients with nonalcoholic fatty liver disease (NAFLD). We compared the performance of the FIB4 index (based on age, aspartate aminotransferase [AST] and alanine aminotransferase [ALT] levels, and platelet counts) with 6 other non-invasive markers of fibrosis in patients with NAFLD.<h4>Methods</h4>Using a nation-wide database of 541 adults with NAFLD, jackknife-validated areas under receiver operating characteristic curves (AUROC) of FIB4 and 7 other markers were compared. The sensitivity at 90% specificity, 80% positive predictive value, and 90% negative predictive values were determined along with cutoffs for advanced fibrosis.<h4>Results</h4>The median FIB4 score was 1.11 (interquartile range = 0.74-1.67). The jackknife-validated AUROC for FIB4 was 0.802 (95% confidence interval [CI], 0.758-0.847), which was higher than that of the NAFLD fibrosis score (0.768; 95% CI, 0.720-0.816; P = .09), Goteburg University Cirrhosis Index (0.743; 95% CI, 0.695-0.791; P < .01), AST:ALT ratio (0.742; 95% CI, 0.690-0.794; P < .015), AST:platelet ratio index (0.730; 95% CI, 0.681-0.779; P < .001), AST:platelet ratio (0.720; 95% CI, 0.669-0.770; P < .001), body mass index, AST:ALT, diabetes (BARD) score (0.70; P < .001), or cirrhosis discriminant score (0.666; 95% CI, 0.614-0.718; P < .001). For a fixed specificity of 90% (FIB4 = 1.93), the sensitivity in identifying advanced fibrosis was only 50% (95% CI, 46-55). A FIB4 > or = 2.67 had an 80% positive predictive value and a FIB4 index < or = 1.30 had a 90% negative predictive value.<h4>Conclusions</h4>The FIB4 index is superior to 7 other noninvasive markers of fibrosis in patients with NAFLD; however its performance characteristics highlight the need for even better noninvasive markers.
Journal Article2009-06-09✓ 1 SnippetGundacker C, Wittmann KJ, Kukuckova M, Komarnicki G, Hikkel I, Gencik M.
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Abstract)
…and polymorphisms inHFE, VDR, ALAD, and…
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<h4>Background</h4>Information on the impact of genetic predisposition on metal toxicokinetics in the human body is limited. There is increasing evidence that certain genetic polymorphisms modify lead and mercury toxicokinetics. This called for analysis of further candidate genes.<h4>Objectives</h4>Medical students (N=324) were examined in order to detect potential associations between lead exposure and polymorphisms in HFE, VDR, ALAD, and MT genes, as well as between mercury exposure and GSTT1, GSTM1, GSTA1, GSTP1, GCLC, and MT polymorphisms.<h4>Methods</h4>The levels of lead and mercury exposure of students were determined by blood, urine, and hair analyses (ICP-MS, CV-AAS). Genotyping of common polymorphisms was examined by MALDI-TOF MS and the TaqMan methodology. Associations between lead and mercury exposures and genetic background were examined by bivariate analysis, and by categorical regression analysis (CATREG) controlled by metal- and matrix-specific variables.<h4>Results</h4>Lead and mercury levels in urine, blood, and hair indicated low exposures. VDR polymorphism and joint presence of VDR/ALAD polymorphisms were significantly and independently associated with urine lead concentrations (CATREG P<0.05). Polymorphisms in GSTP1-114 and MT4 genes as well as dual gene combinations including GSTP1, GCLC, GSTT1, and GSTM1 polymorphisms were independent variables related to mercury body burdens (CATREG P<0.05). GSTP1-114/GSTT1 and GSTP1-105/GCLC combinations showed synergistic effects on hair mercury levels compared to single-gene variants.<h4>Conclusions</h4>We found evidence that certain genetic backgrounds were associated with lead and mercury metabolism, suggesting gene-environment and gene-gene-environment interactions. The modes of interaction remain to be evaluated.
The chemotherapeutic doxorubicin (DOX) induces DNA double-strand break (DSB) damage. In order to identify conserved genes that mediate DOX resistance, we screened the Saccharomyces cerevisiae diploid deletion collection and identified 376 deletion strains in which exposure to DOX was lethal or severely reduced growth fitness. This diploid screen identified 5-fold more DOX resistance genes than a comparable screen using the isogenic haploid derivative. Since DSB damage is repaired primarily by homologous recombination in yeast, and haploid cells lack an available DNA homolog in G1 and early S phase, this suggests that our diploid screen may have detected the loss of repair functions in G1 or early S phase prior to complete DNA replication. To test this, we compared the relative DOX sensitivity of 30 diploid deletion mutants identified under our screening conditions to their isogenic haploid counterpart, most of which (n = 26) were not detected in the haploid screen. For six mutants (bem1Delta, ctf4Delta, ctk1Delta, hfi1Delta,nup133Delta, tho2Delta) DOX-induced lethality was absent or greatly reduced in the haploid as compared to the isogenic diploid derivative. Moreover, unlike WT, all six diploid mutants displayed severe G1/S phase cell cycle progression defects when exposed to DOX and some were significantly enhanced (ctk1Delta and hfi1Delta) or deficient (tho2Delta) for recombination. Using these and other "THO2-like" hypo-recombinogenic, diploid-specific DOX sensitive mutants (mft1Delta, thp1Delta, thp2Delta) we utilized known genetic/proteomic interactions to construct an interactive functional genomic network which predicted additional DOX resistance genes not detected in the primary screen. Most (76%) of the DOX resistance genes detected in this diploid yeast screen are evolutionarily conserved suggesting the human orthologs are candidates for mediating DOX resistance by impacting on checkpoint and recombination functions in G1 and/or early S phases.
Also flagged:WatertaptubeDiarrhoeal Diseaseorganizationtin
Journal Article2009-06-08No SnippetsAngeles G, Lance P, Barden-O'Fallon J, Islam N, Mahbub AQ, Nazem NI.
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<h4>Background</h4>The concentration of poverty and adverse environmental circumstances within slums, particularly those in the cities of developing countries, are an increasingly important concern for both public health policy initiatives and related programs in other sectors. However, there is a dearth of information on the population-level implications of slum life for human health. This manuscript describes the 2005 Census and Mapping of Slums (CMS), which used geographic information systems (GIS) tools and digital satellite imagery combined with more traditional fieldwork methodologies, to obtain detailed, up-to-date and new information about slum life in all slums of six major cities in Bangladesh (including Dhaka).<h4>Results</h4>The CMS found that Bangladeshi slums are very diverse: there are wide intra- and inter-city variations in population size, density, the percent of urban populations living in slums, and sanitation conditions. Findings also show that common beliefs about slums may be outdated; of note, tenure insecurity was found to be an issue in only a small minority of slums.<h4>Conclusion</h4>The methodology used in the 2005 Bangladesh CMS provides a useful approach to mapping slums that could be applied to urban areas in other low income societies. This methodology may become an increasingly important analytic tool to inform policy, as cities in developing countries are forecasted to continue increasing their share of total global population in the coming years, with slum populations more than doubling in size during the same period.
Also flagged:ataxin 2 binding protein 1hand osteoarthritisOAAgingArthrosisA2BP1
Journal Article2009-06-08No SnippetsZhai G, van Meurs JB, Livshits G, Meulenbelt I, Valdes AM, Soranzo N, Hart D, Zhang F, Kato BS, Richards JB, Williams FM, Inouye M, Kloppenburg M, Deloukas P, Slagboom E, Uitterlinden A, Spector TD.
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To identify the susceptibility gene in hand osteoarthritis (OA) the authors used a two-stage approach genome-wide association study using two discovery samples (the TwinsUK cohort and the Rotterdam discovery subset; a total of 1804 subjects) and four replication samples (the Chingford Study, the Chuvasha Skeletal Aging Study, the Rotterdam replication subset and the Genetics, Arthrosis, and Progression (GARP) Study; a total of 3266 people). Five single-nucleotide polymorphisms (SNPs) had a likelihood of association with hand OA in the discovery stage and one of them (rs716508), was successfully confirmed in the replication stage (meta-analysis p = 1.81x10(-5)). The C allele conferred a reduced risk of 33% to 41% using a case-control definition. The SNP is located in intron 1 of the A2BP1 gene. This study also found that the same allele of the SNP significantly reduced bone density at both the hip and spine (p<0.01), suggesting the potential mechanism of the gene in hand OA might be via effects on subchondral bone. The authors' findings provide a potential new insight into genetic mechanisms in the development of hand OA.
Also flagged:gene expressionrheumatoid arthritisinfectionpolymeraseCXCL1HMOX1
Journal Article2009-06-07No SnippetsKarlovich C, Duchateau-Nguyen G, Johnson A, McLoughlin P, Navarro M, Fleurbaey C, Steiner L, Tessier M, Nguyen T, Wilhelm-Seiler M, Caulfield JP.
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<h4>Background</h4>The use of gene expression in venous blood either as a pharmacodynamic marker in clinical trials of drugs or as a diagnostic test requires knowledge of the variability in expression over time in healthy volunteers. Here we defined a normal range of gene expression over 6 months in the blood of four cohorts of healthy men and women who were stratified by age (22-55 years and > 55 years) and gender.<h4>Methods</h4>Eleven immunomodulatory genes likely to play important roles in inflammatory conditions such as rheumatoid arthritis and infection in addition to four genes typically used as reference genes were examined by quantitative reverse transcription-polymerase chain reaction (qRT-PCR), as well as the full genome as represented by Affymetrix HG U133 Plus 2.0 microarrays.<h4>Results</h4>Gene expression levels as assessed by qRT-PCR and microarray were relatively stable over time with approximately 2% of genes as measured by microarray showing intra-subject differences over time periods longer than one month. Fifteen genes varied by gender. The eleven genes examined by qRT-PCR remained within a limited dynamic range for all individuals. Specifically, for the seven most stably expressed genes (CXCL1, HMOX1, IL1RN, IL1B, IL6R, PTGS2, and TNF), 95% of all samples profiled fell within 1.5-2.5 Ct, the equivalent of a 4- to 6-fold dynamic range. Two subjects who experienced severe adverse events of cancer and anemia, had microarray gene expression profiles that were distinct from normal while subjects who experienced an infection had only slightly elevated levels of inflammatory markers.<h4>Conclusion</h4>This study defines the range and variability of gene expression in healthy men and women over a six-month period. These parameters can be used to estimate the number of subjects needed to observe significant differences from normal gene expression in clinical studies. A set of genes that varied by gender was also identified as were a set of genes with elevated expression in a subject with iron deficiency anemia and another subject being treated for lung cancer.
Intellectual disability (ID) is a common developmental disability observed in 1 to 3% of the human population. A possible role for the Angiotensin II type 2 receptor (AGTR2) in brain function, affecting learning, memory, and behavior, has been suggested in humans and rodents. Mice lacking the Agtr2 gene (Agtr2(-/y)) showed significant impairment in their spatial memory and exhibited abnormal dendritic spine morphology. To identify Agtr2 influenced genes and pathways, we performed whole genome microarray analysis on RNA isolated from brains of Agtr2(-/y) and control male mice at embryonic day 15 (E15) and postnatal day one (P1). The gene expression profiles of the Agtr2(-/y) brain samples were significantly different when compared to profiles of the age-matched control brains. We identified 62 differently expressed genes (p< or =0.005) at E15 and in P1 brains of the Agtr2(-/y) mice. We verified the differential expression of several of these genes in brain samples using quantitative RT-PCR. Differentially expressed genes encode molecules involved in multiple cellular processes including microtubule functions associated with dendritic spine morphology. This study provides insight into Agtr2 influenced candidate genes and suggests that expression dysregulation of these genes may modulate Agtr2 actions in the brain that influences learning and memory.
Also flagged:MORbindingfibromyalgiacarfentanilopioid receptorsopioid receptor
Journal Article2009-06-06No SnippetsHarris RE, Zubieta JK, Scott DJ, Napadow V, Gracely RH, Clauw DJ.
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Controversy remains regarding the mechanisms of acupuncture analgesia. A prevailing theory, largely unproven in humans, is that it involves the activation of endogenous opioid antinociceptive systems and mu-opioid receptors (MORs). This is also a neurotransmitter system that mediates the effects of placebo-induced analgesia. This overlap in potential mechanisms may explain the lack of differentiation between traditional acupuncture and either non-traditional or sham acupuncture in multiple controlled clinical trials. We compared both short- and long-term effects of traditional Chinese acupuncture (TA) versus sham acupuncture (SA) treatment on in vivo MOR binding availability in chronic pain patients diagnosed with fibromyalgia (FM). Patients were randomized to receive either TA or SA treatment over the course of 4 weeks. Positron emission tomography (PET) with (11)C-carfentanil was performed once during the first treatment session and then repeated a month later following the eighth treatment. Acupuncture therapy evoked short-term increases in MOR binding potential, in multiple pain and sensory processing regions including the cingulate (dorsal and subgenual), insula, caudate, thalamus, and amygdala. Acupuncture therapy also evoked long-term increases in MOR binding potential in some of the same structures including the cingulate (dorsal and perigenual), caudate, and amygdala. These short- and long-term effects were absent in the sham group where small reductions were observed, an effect more consistent with previous placebo PET studies. Long-term increases in MOR BP following TA were also associated with greater reductions in clinical pain. These findings suggest that divergent MOR processes may mediate clinically relevant analgesic effects for acupuncture and sham acupuncture.
<h4>Unlabelled</h4>The length polymorphism of the serotonin (5-HT) transporter gene promoter region has been implicated in altered 5-HT function and, in turn, neuropsychiatric illnesses, such as anxiety and depression. The nonhuman primate has been used as a model to study anxiety-related mechanisms in humans based upon similarities in behavior and the presence of a similar 5-HT transporter gene polymorphism. Stressful and threatening contexts in the nonhuman primate model have revealed 5-HT transporter genotype dependent differences in regional glucose metabolism. Using the rhesus monkey, we examined the extent to which serotonin transporter genotype is associated with 5-HT transporter binding in brain regions implicated in emotion-related pathology.<h4>Methods</h4>Genotype data and high resolution PET scans were acquired in 29 rhesus (Macaca mulatta) monkeys. [C-11]DASB dynamic PET scans were acquired for 90 min in the anesthetized animals and images of distribution volume ratio (DVR) were created to serve as a metric of 5-HT transporter binding for group comparison based on a reference region method of analysis. Regional and voxelwise statistical analysis were performed with corrections for anatomical differences in gray matter probability, sex, age and radioligand mass.<h4>Results</h4>There were no significant differences when comparing l/l homozygotes with s-carriers in the regions of the brain implicated in anxiety and mood related illnesses (amygdala, striatum, thalamus, raphe nuclei, temporal and prefrontal cortex). There was a significant sex difference in 5-HT transporter binding in all regions with females having 18%-28% higher DVR than males.<h4>Conclusions</h4>Because these findings are consistent with similar genotype findings in humans, this further strengthens the use of the rhesus model for studying anxiety-related neuropathologies.
Hydroxyapatite (HAP) is an important biomedical material that is used for grafting osseous defects. It has an excellent bioactivity and biocompatibility properties. To isolate hydroxyapatite, pieces of cleaned cattle's bone were heated at different temperature range from 400 degrees C up to 1,200 degrees C. A reasonable yield of 60.32% w/w HAP was obtained at temperature range from 1,000 degrees C to 1,200 degrees C. Fourier transform infrared spectra and the thermogravimetric measurement showed a clear removal of organic at 600 degrees C as well as an excellent isolation of HAP from the bones which was achieved at 1,000-1,200 degrees C. This was also confirmed from X-ray diffraction of bone sample heated at 1,200 degrees C. The concentration ions were found to be sodium, potassium, lithium, zinc, copper, iron, calcium, magnesium, and phosphate present in bones within the acceptable limits for its role in the bioactivity property of HAP. Glucose powder was used as a porosifier. Glucose was novel and excellent as porogen where it was completely removed by heating, giving an efficient porosity in the used scaffolds. The results exhibited that the ceftriaxone drug release was increased with increasing the porosity. It was found that a faster, higher, and more regular drug release was obtained from the scaffold with a porosity of 10%.
Also flagged:mitochondrialprotein degradationParkinson's diseasepathogenesisneurodegenerative diseasesdeath
Journal Article2009-06-05✓ 1 SnippetMalkus KA, Tsika E, Ischiropoulos H.
In-Text Gene Mentions
Introduction)
…eurodegenerative disease, APP,Htt, and α-synuclein, all…
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While numerous hypotheses have been proposed to explain the molecular mechanisms underlying the pathogenesis of neurodegenerative diseases, the theory of oxidative stress has received considerable support. Although many correlations have been established and encouraging evidence has been obtained, conclusive proof of causation for the oxidative stress hypothesis is lacking and potential cures have not emerged. Therefore it is likely that other factors, possibly in coordination with oxidative stress, contribute to neuron death. Using Parkinson's disease (PD) as the paradigm, this review explores the hypothesis that oxidative modifications, mitochondrial functional disruption, and impairment of protein degradation constitute three interrelated molecular pathways that execute neuron death. These intertwined events are the consequence of environmental exposure, genetic factors, and endogenous risks and constitute a "Bermuda triangle" that may be considered the underlying cause of neurodegenerative pathogenesis.
Also flagged:brain-derived neurotrophic factorserotonin transporterserotonin-1A receptorBDNFserotonin-1A (5-HT1A) receptor
Journal Article2009-06-05✓ 5 SnippetsHenningsson S, Borg J, Lundberg J, Bah J, Lindström M, Ryding E, Jovanovic H, Saijo T, Inoue M, Rosén I, Träskman-Bendz L, Farde L, Eriksson E.
In-Text Gene Mentions
Abstract)
…<h4>Background</h4>The serotonergic system, including the serotonin transporter (5-HTT), which is the target of many antidepressants, seems to be influenced by brain-derived neurotrophic factor (BDNF).<h4>Methods</h4>Positron emission tomography (PET) was used to address, in 25 and 53 healthy volunteers, respectively, the possible association between six polymorphisms in the gene encoding BDNF and the availability of two proteins expressed by serotonergic neurons: the 5-HTT, measured with the radioligand [(11)C]MADAM, and the serotonin-1A (5-HT1A) receptor, measured with [(11)C]WAY-100635.<h4>Results</h4>Several single nucleotide polymorphisms were associated with [(11)C]MADAM binding potential (BP) in most brain regions, male carriers of the valine/valine genotype of the Val66Met polymorphism displaying higher availability.…
Abstract)
…the serotonin transporter (5-HTT), which is the…
Abstract)
…serotonergic neurons: the5-HTT, measured with the…
Abstract)
…were associated with5-HTTavailability could be…
Abstract)
…in BDNF influences5-HTTbut not 5-HT1A…
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<h4>Background</h4>The serotonergic system, including the serotonin transporter (5-HTT), which is the target of many antidepressants, seems to be influenced by brain-derived neurotrophic factor (BDNF).<h4>Methods</h4>Positron emission tomography (PET) was used to address, in 25 and 53 healthy volunteers, respectively, the possible association between six polymorphisms in the gene encoding BDNF and the availability of two proteins expressed by serotonergic neurons: the 5-HTT, measured with the radioligand [(11)C]MADAM, and the serotonin-1A (5-HT1A) receptor, measured with [(11)C]WAY-100635.<h4>Results</h4>Several single nucleotide polymorphisms were associated with [(11)C]MADAM binding potential (BP) in most brain regions, male carriers of the valine/valine genotype of the Val66Met polymorphism displaying higher availability. Effect sizes ranged from a 50% to a threefold increase. In contrast, there was no association for [(11)C]WAY-100635 BP. The observation that BDNF polymorphisms were associated with 5-HTT availability could be partly replicated in an independent population comprising nine male suicide attempters and nine matched control subjects, in which transporter availability had been measured with single photon emission computed tomography with (123)I-beta-CIT as ligand.<h4>Conclusions</h4>Our results suggest that genetic variation in BDNF influences 5-HTT but not 5-HT1A receptor density in the human brain.
Also flagged:gene expressionsepsiscell cycletranscription factorinfectiondeath
Journal Article2009-06-05No SnippetsHussein S, Michael P, Brabant D, Omri A, Narain R, Passi K, Ramana CV, Parrillo JE, Kumar A, Parissenti A, Kumar A.
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To gain a better understanding of the gene expression changes that occurs during sepsis, we have performed a cDNA microarray study utilizing a tissue culture model that mimics human sepsis. This study utilized an in vitro model of cultured human fetal cardiac myocytes treated with 10% sera from septic patients or 10% sera from healthy volunteers. A 1700 cDNA expression microarray was used to compare the transcription profile from human cardiac myocytes treated with septic sera vs normal sera. Septic sera treatment of myocytes resulted in the down-regulation of 178 genes and the up-regulation of 4 genes. Our data indicate that septic sera induced cell cycle, metabolic, transcription factor and apoptotic gene expression changes in human myocytes. Identification and characterization of gene expression changes that occur during sepsis may lead to the development of novel therapeutics and diagnostics.
Also flagged:Cyclin-dependent kinase 5Cdk5proline-directed serine/threonine kinaseneurological disordersNMDARdegradation
Journal Article2009-06-04No SnippetsHawasli AH, Koovakkattu D, Hayashi K, Anderson AE, Powell CM, Sinton CM, Bibb JA, Cooper DC.
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Cyclin-dependent kinase 5 (Cdk5) is a proline-directed serine/threonine kinase that has been implicated in learning, synaptic plasticity, neurotransmission, and numerous neurological disorders. We previously showed that conditional loss of Cdk5 in adult mice enhanced hippocampal learning and plasticity via modulation of calpain-mediated N-methyl-D-aspartic acid receptor (NMDAR) degradation. In the present study, we characterize the enhanced synaptic plasticity and examine the effects of long-term Cdk5 loss on hippocampal excitability in adult mice. Field excitatory post-synaptic potentials (fEPSPs) from the Schaffer collateral CA1 subregion of the hippocampus (SC/CA1) reveal that loss of Cdk5 altered theta burst topography and enhanced post-tetanic potentiation. Since Cdk5 governs NMDAR NR2B subunit levels, we investigated the effects of long-term Cdk5 knockout on hippocampal neuronal excitability by measuring NMDAR-mediated fEPSP magnitudes and population-spike thresholds. Long-term loss of Cdk5 led to increased Mg(2+)-sensitive potentials and a lower threshold for epileptiform activity and seizures. Biochemical analyses were performed to better understand the role of Cdk5 in seizures. Induced-seizures in wild-type animals led to elevated amounts of p25, the Cdk5-activating cofactor. Long-term, but not acute, loss of Cdk5 led to decreased p25 levels, suggesting that Cdk5/p25 may be activated as a homeostatic mechanism to attenuate epileptiform activity. These findings indicate that Cdk5 regulates synaptic plasticity, controls neuronal and behavioral stimulus-induced excitability and may be a novel pharmacological target for cognitive and anticonvulsant therapies.
Also flagged:Nrf2detoxificationnuclear factor erythroid-2-related factor 2transcription factorsleucinesynthesis
Journal Article2009-06-03No SnippetsVargas MR, Johnson JA.
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The expression of phase-II detoxification and antioxidant enzymes is governed by a cis-acting regulatory element named the antioxidant response element (ARE). ARE-containing genes are regulated by the nuclear factor erythroid-2-related factor 2 (Nrf2), a member of the Cap'n'Collar basic-leucine-zipper family of transcription factors. ARE-regulated genes are preferentially activated in astrocytes, which consequently have more efficient detoxification and antioxidant defences than neurons. Astrocytes closely interact with neurons to provide structural, metabolic and trophic support, as well as actively participating in the modulation of neuronal excitability and neurotransmission. Therefore, functional alterations in astrocytes can shape the interaction with surrounding cells, such as neurons and microglia. Activation of Nrf2 in astrocytes protects neurons from a wide array of insults in different in vitro and in vivo paradigms, confirming the role of astrocytes in determining the vulnerability of neurons to noxious stimuli. Here, we review the current data supporting Nrf2 activation in astrocytes as a viable therapeutic approach, not only in acute neuronal damage, but also in chronic neurodegeneration related to oxidative stress.
Journal Article2009-06-03✓ 5 SnippetsMcRonald FE, Morris MR, Gentle D, Winchester L, Baban D, Ragoussis J, Clarke NW, Brown MD, Kishida T, Yao M, Latif F, Maher ER.
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I A O 0000326)
…DCC…
Results)
…However, although, on average, pRCC were smaller than wtVHL-cRCC, tumour-specific CpG methylation was generally higher in pRCC (see above) and 12 genes were more frequently methylated in pRCC than in wtVHL-cRCC (SERPINE1, HOXC6, HOXA11, JAK3, ITGB1, PDGFRB, RARB, GSTM2, MYOD1, SMARCA3(HTLF), GABRB3 and TGFB2), whereas only 5 genes were more frequently methylated in wtVHL-cRCC than pRCC (TWIST1, TIAM1, DCC, CDH1 and PTGS2) (all at p ≤ 0.025 (see Additional file 2)), There was a significantly positive correlation (Pearson product-moment correlation coefficient; p < 0.05) between tumour size and gene methylation in only three genes with differential methylation between tumour types (PDGFRB, TIAM1 and GSTM2), suggesting that in most cases the observed differential methylation is related to different tumour histologies rather than to tumour size.…
Results)
…For genes more methylated in wtVHL than VHL-RCC, RASSF1, PITX2, CDH13, HS3ST2, TAL1, TUSC3 and DCC were at least as frequently methylated in tumours < 5 cm as those ≥ 5 cm.…
Discussion)
…We found that a number of loci, including RASSF1, PITX2, CDH13, HS3ST2, TWIST1, TAL1, TUSC3 and DCC were significantly more frequently methylated in VHL-wt sporadic RCC than in VHL RCC.…
Results)
…Comparison of methylation patterns in VHL cRCC and sporadic wtVHL cRCC demonstrated that 11 frequently methylated genes (i.e. genes methylated in > 20% of at least one tumour type) were significantly (p < 0.025) more frequently methylated in wtVHL sporadic RCC than in VHL RCC (RASSF1, TWIST1 PITX2, CDH13, HS3ST2, TAL1, WT1, MMP2, DCC, ICA1 and TUSC3:(all p < 0.025; log-likelihood G-test; see Additional file 2).…
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<h4>Background</h4>Renal cell carcinoma (RCC) is histopathologically heterogeneous with clear cell and papillary the most common subtypes. The most frequent molecular abnormality in clear cell RCC is VHL inactivation but promoter methylation of tumour suppressor genes is common in both subtypes of RCC. To investigate whether RCC CpG methylation status was influenced by histopathology and VHL status we performed high-throughput epigenetic profiling using the Illumina Goldengate Methylation Array in 62 RCC (29 RCC from von Hippel-Lindau (VHL) disease patients, 20 sporadic clear cell RCC with wild type VHL and 13 sporadic papillary RCC).<h4>Results</h4>43 genes were methylated in >20% of primary RCC (range 20-45%) and most (37/43) of these had not been reported previously to be methylated in RCC. The distribution of the number of methylated CpGs in individual tumours differed from the expected Poisson distribution (p < 0.00001; log-likelihood G test) suggesting that a subset of RCC displayed a CpG Island Methylator Phenotype. Comparison of RCC subtypes revealed that, on average, tumour specific CpG methylation was most prevalent in papillary RCC and least in VHL RCC. Many of the genes preferentially methylated in pRCC were linked to TGFbeta or ERK/Akt signalling.<h4>Conclusion</h4>These findings demonstrate differing patterns of tumour-specific CpG methylation in VHL and non VHL clear cell RCC and papillary RCC, and identify multiple novel potential CpG methylation biomarkers for RCC.
Also flagged:hydroxyapatitecellminerallaminincalciumhydroxide
Journal Article2009-06-03No SnippetsLi X, Koller G, Huang J, Di Silvio L, Renton T, Esat M, Bonfield W, Edirisinghe M.
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Surface topography is well known to play a crucial role in influencing cellular responses to an implant material and is therefore important in bone tissue regeneration. A novel jet-based patterning technique, template-assisted electrohydrodynamic atomization spraying, was recently devised to control precisely the surface structure as well as its dimensions. In the present study, a detailed investigation of this patterning process was carried out. A range of nano-hydroxyapatite (nHA) line-shaped patterns <20 microm in width were successfully deposited on a commercially pure Ti surface by controlling the flow of an nHA suspension in an electric field. In vitro studies showed that the nHA patterns generated are capable of regulating the human osteoblast cell attachment and orientation.
Also flagged:peptide hormoneironmetabolismHepcidiniron deficiency
Journal Article2009-06-03✓ 1 SnippetGrebenchtchikov N, Geurts-Moespot AJ, Kroot JJ, den Heijer M, Tjalsma H, Swinkels DW, Sweep FG.
In-Text Gene Mentions
Abstract)
…individuals of differentHFE-genotypes (n = 60)…
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The hepatic peptide hormone hepcidin plays a central role in body iron metabolism. Despite its promise as a biomarker, the availability of high-sensitive hepcidin assays is still limited. We developed and validated a RadioImmunoAssay (RIA) to measure hepcidin quantitatively in human serum. This assay exhibited a very low detection limit (0.02 microg/l), low imprecision (coefficient of variation-range 4.4-6.2%) and good linearity and recovery (range: 81-105%). Hepcidin levels of samples of controls and patients with iron deficiency and inflammation showed an excellent correlation with our previously described quantitative time-of-flight mass spectrometry assay (range 2.5-266.8 microg/l, r = 0.92, P < 0.0001). The RIA detected: (i) differences in mean hepcidin levels between men (n = 29) and women (n = 35), (ii) differences between individuals of different HFE-genotypes (n = 60) and (iii) daily increases in hepcidin levels (n = 64). The assay (i) is easy to perform and many samples can be processed within one assay-run, (ii) shows accurate, reproducible and high-sensitive measurements and (iii) is anticipated to be particularly useful to study the effects of pathological and physiological stimuli on hepcidin levels in the lower range.
Also flagged:pathogenesisneurodegenerative disorderssynapsesAmyotrophic Lateral Sclerosisatrophy ofAD
Journal Article2009-06-03No SnippetsChoonara YE, Pillay V, Du Toit LC, Modi G, Naidoo D, Ndesendo VMK, Sibambo SR.
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The term neurodegenerative disorders, encompasses a variety of underlying conditions, sporadic and/or familial and are characterized by the persistent loss of neuronal subtypes. These disorders can disrupt molecular pathways, synapses, neuronal subpopulations and local circuits in specific brain regions, as well as higher-order neural networks. Abnormal network activities may result in a vicious cycle, further impairing the integrity and functions of neurons and synapses, for example, through aberrant excitation or inhibition. The most common neurodegenerative disorders are Alzheimer's disease, Parkinson's disease, Amyotrophic Lateral Sclerosis and Huntington's disease. The molecular features of these disorders have been extensively researched and various unique neurotherapeutic interventions have been developed. However, there is an enormous coercion to integrate the existing knowledge in order to intensify the reliability with which neurodegenerative disorders can be diagnosed and treated. The objective of this review article is therefore to assimilate these disorders' in terms of their neuropathology, neurogenetics, etiology, trends in pharmacological treatment, clinical management, and the use of innovative neurotherapeutic interventions.
Hepatic angiosarcoma is a rare malignant vascular tumor, which accounts for up to 2% of all primary liver tumors. The most frequent symptoms on presentation are weight loss, weakness and abdominal pain. Diagnosis of diffuse hepatic angiosarcoma can be challenging. We report an original case of diffuse liver angiosarcoma revealed by haematological abnormalities initially diagnosed as an Evans syndrome. Anaemia and thrombocytopenia are rarely the first manifestations of this pathology. They are explained by combination of several mechanisms. Diagnosis of diffuse liver angiosarcoma can be extremely difficult and physicians should be aware of these presentation.
Also flagged:pathogenesisHuntington's diseaseHDproteolysissodiumsalicylate
Journal Article2009-06-02✓ 5 SnippetsKhoshnan A, Ko J, Tescu S, Brundin P, Patterson PH.
In-Text Gene Mentions
S I O 001029)
…Inhibition of IKKβ prevents proteolysis of Htt induced by etoposide.…
S I O 001029)
…Etoposide induces proteolysis of endogenous mutant Htt in neurons striatal (HdhQ111/Q111) neurons.…
Discussion)
…Identification of the IKKs as regulators of Htt proteolysis offers novel targets to search for molecules that prevent one of the earliest events in HD pathogenesis.…
Results)
…Generation of N-terminal fragments of mutant Htt is thought to initiate neurotoxicity, culminating in HD [2]–[4].…
Results)
…The prosurvival protein Bcl-xL, which is abundant in the CNS, has recently been implicated in Htt proteolysis in a chemical model of HD [32]–[33].…
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<h4>Background</h4>Proteolysis of huntingtin (Htt) plays a key role in the pathogenesis of Huntington's disease (HD). However, the environmental cues and signaling pathways that regulate Htt proteolysis are poorly understood. One stimulus may be the DNA damage that accumulates in neurons over time, and the subsequent activation of signaling pathways such as those regulated by IkappaB kinase (IKK), which can influence neurodegeneration in HD.<h4>Methodology/principal findings</h4>We asked whether DNA damage induces the proteolysis of Htt and if activation of IKK plays a role. We report that treatment of neurons with the DNA damaging agent etoposide or gamma-irradiation promotes cleavage of wild type (WT) and mutant Htt, generating N-terminal fragments of 80-90 kDa. This event requires IKKbeta and is suppressed by IKKalpha. Elevated levels of IKKalpha, or inhibition of IKKbeta expression by a specific small hairpin RNA (shRNA) or its activity by sodium salicylate, prevents Htt proteolysis and increases neuronal resistance to DNA damage. Moreover, IKKbeta phosphorylates the anti-apoptotic protein Bcl-xL, a modification known to reduce Bcl-xL levels, and activates caspases that can cleave Htt. When IKKbeta expression is blocked, etoposide treatment does not decrease Bcl-xL and activation of caspases is diminished. Similar to silencing of IKKbeta, increasing the level of Bcl-xL in neurons prevents etoposide-induced caspase activation and Htt proteolysis.<h4>Conclusions/significance</h4>These results indicate that DNA damage triggers cleavage of Htt and identify IKKbeta as a prominent regulator. Moreover, IKKbeta-dependent reduction of Bcl-xL is important in this process. Thus, inhibition of IKKbeta may promote neuronal survival in HD as well as other DNA damage-induced neurodegenerative disorders.
Also flagged:Hypoxia Inducible Factor-1HIF-1transcription factorHypoxia-inducible factor 1response tooxygen
Journal Article2009-06-02No SnippetsBenita Y, Kikuchi H, Smith AD, Zhang MQ, Chung DC, Xavier RJ.
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The transcription factor Hypoxia-inducible factor 1 (HIF-1) plays a central role in the transcriptional response to oxygen flux. To gain insight into the molecular pathways regulated by HIF-1, it is essential to identify the downstream-target genes. We report here a strategy to identify HIF-1-target genes based on an integrative genomic approach combining computational strategies and experimental validation. To identify HIF-1-target genes microarrays data sets were used to rank genes based on their differential response to hypoxia. The proximal promoters of these genes were then analyzed for the presence of conserved HIF-1-binding sites. Genes were scored and ranked based on their response to hypoxia and their HIF-binding site score. Using this strategy we recovered 41% of the previously confirmed HIF-1-target genes that responded to hypoxia in the microarrays and provide a catalogue of predicted HIF-1 targets. We present experimental validation for ANKRD37 as a novel HIF-1-target gene. Together these analyses demonstrate the potential to recover novel HIF-1-target genes and the discovery of mammalian-regulatory elements operative in the context of microarray data sets.
Also flagged:polyglutamineHuntington diseaseHDneurodegenerative disorderinclusion bodiesantibodies
Journal Article2009-06-02✓ 5 SnippetsLegleiter J, Lotz GP, Miller J, Ko J, Ng C, Williams GL, Finkbeiner S, Patterson PH, Muchowski PJ.
In-Text Gene Mentions
Abstract)
…Huntington disease (HD) is a neurodegenerative disorder caused by an expansion of a polyglutamine (polyQ) domain in the N-terminal region of huntingtin (htt).…
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…region of huntingtin (htt).…
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…disease associated withhttaggregation into inclusion…
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…of a mutanthtt-exon1 fragment.…
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…a panel of anti-httantibodies (MW1–MW5, MW7,…
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Huntington disease (HD) is a neurodegenerative disorder caused by an expansion of a polyglutamine (polyQ) domain in the N-terminal region of huntingtin (htt). PolyQ expansion above 35-40 results in disease associated with htt aggregation into inclusion bodies. It has been hypothesized that expanded polyQ domains adopt multiple potentially toxic conformations that belong to different aggregation pathways. Here, we used atomic force microscopy to analyze the effect of a panel of anti-htt antibodies (MW1-MW5, MW7, MW8, and 3B5H10) on aggregate formation and the stability of a mutant htt-exon1 fragment. Two antibodies, MW7 (polyproline-specific) and 3B5H10 (polyQ-specific), completely inhibited fibril formation and disaggregated preformed fibrils, whereas other polyQ-specific antibodies had widely varying effects on aggregation. These results suggest that expanded polyQ domains adopt multiple conformations in solution that can be readily distinguished by monoclonal antibodies, which has important implications for understanding the structural basis for polyQ toxicity and the development of intrabody-based therapeutics for HD.
Also flagged:serotonin5-HTbulimia nervosa5-HT2a receptor5-HT transporter-
Journal Article2009-06-02✓ 3 SnippetsRacine SE, Culbert KM, Larson CL, Klump KL.
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Abstract)
…Although the T allele of the 5-HT2a receptor gene and the s allele of the 5-HTT gene were associated with higher levels of impulsivity, there were no main effects of 5-HT genotypes on any binge eating measure, and interactions between genotypes, impulsivity, and dietary restraint were non-significant.…
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…allele of the5-HTTgene were associated…
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Although serotonin (5-HT) genes are thought to be involved in the etiology of bulimia nervosa and binge eating, findings from molecular genetic studies are inconclusive. This may be due to limitations of past research, such as a failure to consider the influence of quantitative traits and gene-environment interactions. The current study investigated these issues by examining whether quantitative traits (i.e., impulsivity) and environmental exposure factors (i.e., dietary restraint) moderate 5-HT gene/binge eating associations in a sample of young women (N = 344). Binge eating was assessed using the Minnesota Eating Behavior Survey and the Dutch Eating Behavior Questionnaire (DEBQ). Impulsivity was assessed with the Barratt Impulsiveness Scale-Version 11. Dietary restraint was measured with a factor score derived from common restraint scales. Saliva samples were genotyped for the 5-HT2a receptor T102C polymorphism and 5-HT transporter promoter polymorphism. As expected, impulsivity and dietary restraint were associated with binge eating. Although the T allele of the 5-HT2a receptor gene and the s allele of the 5-HTT gene were associated with higher levels of impulsivity, there were no main effects of 5-HT genotypes on any binge eating measure, and interactions between genotypes, impulsivity, and dietary restraint were non-significant. In conclusion, we found no evidence to suggest that dietary restraint or impulsivity moderate associations between binge eating and these 5-HT genes. Future research should continue to explore interaction effects by examining larger samples, assessing dietary intake directly, and investigating other genes, traits, and environmental factors that may be related to binge eating and bulimia nervosa.
Also flagged:chromosomephosphoinositideinsulin receptorlipidfocal adhesionfatty acid
Journal Article2009-06-02✓ 2 SnippetsGu J, Orr N, Park SD, Katz LM, Sulimova G, MacHugh DE, Hill EW.
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…As well as IRS1, genes in the T2DM KEGG pathway in selected regions included CACNA1G (calcium channel, voltage-dependent, T type, alpha 1G subunit) and CACNA1E (calcium channel, voltage-dependent, R type, alpha 1E subunit) within which polymorphisms have been linked with T2DM [42].…
Thoroughbred horses have been selected for exceptional racing performance resulting in system-wide structural and functional adaptations contributing to elite athletic phenotypes. Because selection has been recent and intense in a closed population that stems from a small number of founder animals Thoroughbreds represent a unique population within which to identify genomic contributions to exercise-related traits. Employing a population genetics-based hitchhiking mapping approach we performed a genome scan using 394 autosomal and X chromosome microsatellite loci and identified positively selected loci in the extreme tail-ends of the empirical distributions for (1) deviations from expected heterozygosity (Ewens-Watterson test) in Thoroughbred (n = 112) and (2) global differentiation among four geographically diverse horse populations (F(ST)). We found positively selected genomic regions in Thoroughbred enriched for phosphoinositide-mediated signalling (3.2-fold enrichment; P<0.01), insulin receptor signalling (5.0-fold enrichment; P<0.01) and lipid transport (2.2-fold enrichment; P<0.05) genes. We found a significant overrepresentation of sarcoglycan complex (11.1-fold enrichment; P<0.05) and focal adhesion pathway (1.9-fold enrichment; P<0.01) genes highlighting the role for muscle strength and integrity in the Thoroughbred athletic phenotype. We report for the first time candidate athletic-performance genes within regions targeted by selection in Thoroughbred horses that are principally responsible for fatty acid oxidation, increased insulin sensitivity and muscle strength: ACSS1 (acyl-CoA synthetase short-chain family member 1), ACTA1 (actin, alpha 1, skeletal muscle), ACTN2 (actinin, alpha 2), ADHFE1 (alcohol dehydrogenase, iron containing, 1), MTFR1 (mitochondrial fission regulator 1), PDK4 (pyruvate dehydrogenase kinase, isozyme 4) and TNC (tenascin C). Understanding the genetic basis for exercise adaptation will be crucial for the identification of genes within the complex molecular networks underlying obesity and its consequential pathologies, such as type 2 diabetes. Therefore, we propose Thoroughbred as a novel in vivo large animal model for understanding molecular protection against metabolic disease.
…based on theantithrombin-IIIheparin-binding domain, hepari…
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This research evaluated the controlled release of glial-derived neurotrophic factor (GDNF) from an affinity-based delivery system (ABDS) as potential treatment for peripheral nerve injury. The ABDS consisted of a bidomain peptide containing a transglutaminase substrate, allowing crosslinking into fibrin matrices, and a heparin-binding domain based on the antithrombin-III heparin-binding domain, heparin, and GDNF, which was sequestered based on its heparin-binding affinity. The objective of this research was to determine the release rate and biological activity of GDNF released from the ABDS in vitro. The ratio of peptide to heparin was found to modulate the rate of GDNF release. The biological activity of GDNF released from the ABDS was assayed using chick dorsal root ganglia (DRGs) neurite extension. Neurite extension was equivalent for fibrin matrices containing the ABDS for all concentrations of GDNF tested versus DRGs grown with GDNF in the media. Furthermore, neurite extension was enhanced in fibrin matrices containing 100 ng/mL of GDNF with the ABDS versus matrices with GDNF at a simliar dose but no ABDS. These results suggest that GDNF can be retained and released in a biologically activity form from the ABDS, and thus this approach may prove useful for the treatment of peripheral nerve injury.
Also flagged:serotonin transporterSLC6A4bipolar disorderserotoninbindingtransporter
Journal Article2009-06-01✓ 3 SnippetsAlaerts M, Ceulemans S, Forero D, Moens LN, De Zutter S, Heyrman L, Lenaerts AS, Norrback KF, Goossens D, De Rijk P, Nilsson LG, Adolfsson R, Del-Favero J.
In-Text Gene Mentions
Abstract)
…Through active reuptake of serotonin into presynaptic neurons, the serotonin transporter (5-HTT) plays an important role in regulating serotonin concentrations in the brain, and it is the site of binding for tricyclic antidepressants and selective serotonin reuptake inhibitors (SSRIs).…
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…the serotonin transporter (5-HTT) plays an important…
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…SLC6A4 gene encoding5-HTTreported in literature…
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Through active reuptake of serotonin into presynaptic neurons, the serotonin transporter (5-HTT) plays an important role in regulating serotonin concentrations in the brain, and it is the site of binding for tricyclic antidepressants and selective serotonin reuptake inhibitors (SSRIs). Therefore it has been hypothesized that this transporter is involved in the etiology of bipolar (BP) disorder. Inconsistent association study results for the SLC6A4 gene encoding 5-HTT reported in literature emphasize the need for more systematic and detailed analyses of this candidate gene. We performed an extensive analysis of SLC6A4 on DNA of 254 BPI patients and 364 control individuals from a Northern Swedish isolated population. This analysis consisted of a HapMap LD-based association study including three widely investigated polymorphisms (5-HTTVNTR, 5-HTTLPR, and rs3813034), a copy-number variation (CNV) analysis and a mutation analysis of the complete coding sequence and the 3'-UTR of SLC6A4. No single marker showed statistically significant association with BPI, nor did any of the haplotypes. In the mutation analysis 13 novel variants were detected, including 2 amino acid substitutions M389V and I587L, but these are probably not implicated in risk for BP. No deletions or duplications were detected in the CNV analysis. We conclude that variation in the SLC6A4 gene or its regulatory regions does not contribute to the susceptibility for BP disorder in the Northern Swedish population.
Phytoestrogens (PEs) are non-steroidal ligands, which regulate the expression of number of estrogen receptor-dependent genes responsible for a variety of biological processes. Deciphering the molecular mechanism of action of these compounds is of great importance because it would increase our understanding of the role(s) these bioactive chemicals play in prevention and treatment of estrogen-based diseases. In this study, we applied suppression subtractive hybridization (SSH) to identify genes that are regulated by PEs through either the classic nuclear-based estrogen receptor or membrane-based estrogen receptor pathways. SSH, using mRNA from genistein (GE) treated MCF-7 cells as testers, resulted in a significant increase in GNB1 mRNA expression levels as compared with 10 nM 17beta estradiol or the no treatment control. GNB1 mRNA expression was up regulated two- to fivefold following exposure to 100.0 nM GE. Similarly, GNB1 protein expression was up regulated 12- to 14-fold. GE regulation of GNB1 was estrogen receptor-dependent, in the presence of the anti-estrogen ICI-182,780, both GNB1 mRNA and protein expression were inhibited. Analysis of the GNB1 promoter using ChIP assay showed a PE-dependent association of estrogen receptor alpha (ERalpha) and beta (ERbeta) to the GNB1 promoter. This association was specific for ERalpha since association was not observed when the cells were co-incubated with GE and the ERalpha antagonist, ICI. Our data demonstrate that the levels of G-protein, beta-1 subunit are regulated by PEs through an estrogen receptor pathway and further suggest that PEs may control the ratio of alpha-subunit to beta/gamma-subunits of the G-protein complex in cells. J. Cell. Physiol. 219: 584-594, 2009. (c) 2009 Wiley-Liss, Inc.
Also flagged:androgen receptorphosphorylationprostate cancerARERK kinaseMBP
Journal Article2009-06-01No SnippetsShigemura K, Isotani S, Wang R, Fujisawa M, Gotoh A, Marshall FF, Zhau HE, Chung LW.
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<h4>Background</h4>Accumulated evidence suggests stromal-epithelial interactions are critical to the progression of prostate cancer. In this study, we characterized AR phosphorylation in LNCaP cells co-cultured with the conditioned medium (CM) from human prostate stromal fibroblasts.<h4>Methods</h4>CM harvested from prostate stromal fibroblasts was added to LNCaP cells, and both anchorage-dependent and -independent growth was determined. Status of AR phosphorylation at Ser-81 and Ser-213 was assessed by immunoblot analysis. ERK kinase activity was measured using MBP-2 protein as the substrate.<h4>Results</h4>The growth of LNCaP cells on plastic dishes increased by 1.7-fold upon exposure to stromal CM or androgen, and their combination resulted in additive growth (2.4-fold). Anchorage-independent growth of LNCaP cells in soft agar, however, was induced synergistically at 80-fold by both stromal CM and androgen. Stromal CM or androgen alone induced LNCaP cell growth by 10- and 26-fold, respectively. We observed ERK kinase inhibitor, U0126, but not phosphatidylinositol 3-kinase (PI-3K), LY294002, or protein kinase A (PKA) inhibitor, H-89, inhibited stromal CM or androgen-induced PSA promoter luciferase activities, and anchorage-independent growth of LNCaP cells. Our results demonstrated for the first time how stromal CM acts in synergy with androgen by activation of ERK kinase and AR phosphorylation at Ser-81 but not Ser-213, for AR-regulated PSA promoter and anchorage-independent growth of human prostate cancer cells.<h4>Conclusions</h4>A stromal factor-activated ERK pathway mediated by AR phosphorylation at Ser-81 could be responsible for stimulating the growth of human prostate cancer cells.
Also flagged:chaperonesresponse to oxidative stressperoxiredoxinscysteineschaperonedisulfide
Journal Article2009-06-01No SnippetsKumsta C, Jakob U.
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Redox regulation of stress proteins, such as molecular chaperones, guarantees an immediate response to oxidative stress conditions. This review focuses on the two major classes of redox-regulated chaperones, Hsp33 in bacteria and typical 2-Cys peroxiredoxins in eukaryotes. Both proteins employ redox-sensitive cysteines, whose oxidation status directly controls their affinity for unfolding proteins and therefore their chaperone function. We will first discuss Hsp33, whose oxidative stress-induced disulfide bond formation triggers the partial unfolding of the chaperone, which, in turn, leads to the exposure of a high-affinity binding site for unfolded proteins. This rapid mode of activation makes Hsp33 essential for protecting bacteria against severe oxidative stress conditions, such as hypochlorite (i.e., bleach) treatment, which leads to widespread protein unfolding and aggregation. We will compare Hsp33 to the highly abundant eukaryotic typical 2-Cys peroxiredoxin, whose oxidative stress-induced sulfinic acid formation turns the peroxidase into a molecular chaperone in vitro and presumably in vivo. These examples illustrate how proteins use reversible cysteine modifications to rapidly adjust to oxidative stress conditions and demonstrate that redox regulation plays a vital role in protecting organisms against reactive oxygen species-mediated cell death.
Classical Ehlers-Danlos syndrome (EDS) is a heritable disorder characterized by joint hypermobility, skin hyperextensibility, and abnormal wound healing. The majority of affected individuals have alterations in 1 of the 2 type V collagen genes, COL5A1 and COL5A2. The most common mechanism is COL5A1 haploinsufficiency due to instability of the transcript of one allele. In dermal fibroblasts from our population of 76 individuals with clinical features of classical EDS, there were 21 (29.5%) with decreased expression of one COL5A1 allele, consistent with published estimates of the frequency of null alleles. We identified the causative mutation in nine of these cell strains (mutations for seven others had been previously described), and found two nonsense mutations, five splice mutations, and two insertion/deletions. The same type of genomic change at splice sites can have different effects at the RNA level and the outcome could not be predicted from the primary genomic DNA alteration.
Also flagged:BRAForganorutheniumserine/threonine kinasecancersV600Ekinase
Journal Article2009-06-01No SnippetsXie P, Streu C, Qin J, Bregman H, Pagano N, Meggers E, Marmorstein R.
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Substitution mutations in the BRAF serine/threonine kinase are found in a variety of human cancers. Such mutations occur in approximately 70% of human malignant melanomas, and a single hyperactivating V600E mutation is found in the activation segment of the kinase domain and accounts for more than 90% of these mutations. Given this correlation, the molecular mechanism for BRAF regulation as well as oncogenic activation has attracted considerable interest, and activated forms of BRAF, such as BRAF(V600E), have become attractive targets for small molecule inhibition. Here we report on the identification and subsequent optimization of a potent BRAF inhibitor, CS292, based on an organometallic kinase inhibitor scaffold. A cocrystal structure of CS292 in complex with the BRAF kinase domain reveals that CS292 binds to the ATP binding pocket of the kinase and is an ATP competitive inhibitor. The structure of the kinase-inhibitor complex also demonstrates that CS292 binds to BRAF in an active conformation and suggests a mechanism for regulation of BRAF by phosphorylation and BRAF(V600E) oncogene-induced activation. The structure of CS292 bound to the active form of the BRAF kinase also provides a novel scaffold for the design of BRAF(V600E) oncogene selective BRAF inhibitors for therapeutic application.
Also flagged:Chromosomenuclear hormone receptorsteroidogenesisgonadogenesisSry box
Journal Article2009-06-01✓ 5 SnippetsOhe K, Tamai KT, Parvinen M, Sassone-Corsi P.
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Abstract)
…We conclude that DAX-1 and SOX6 proteins interact, have overlapped expression in the testis, and act antagonistically during pre-mRNA splicing.…
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…DAX-1 andSOX6molecular interplay results…
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…was performed andSOX6, member of the…
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…and expression ofSOX6overlapped with that…
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…the addition ofSOX6.…
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DAX-1 (DSS-AHC Critical Region on the X Chromosome-1) is a member of the nuclear hormone receptor superfamily that has an important role in steroidogenesis and gonadogenesis. To investigate the role of DAX-1 in the testis, a yeast two-hybrid screen was performed and SOX6, member of the Sry box (SOX) protein family, was cloned as candidate. The interaction was confirmed biochemically and expression of SOX6 overlapped with that of DAX-1 in the developing gonad, as well as in Sertoli cells of the adult testis. We show here that DAX-1 is able to inhibit splicing in in vivo and in vitro splicing assays, and this inhibition is relieved by the addition of SOX6. SOX6 appears to inhibit the interaction between DAX-1 and the splicing machinery, thus providing a likely mechanism for functional interference. We conclude that DAX-1 and SOX6 proteins interact, have overlapped expression in the testis, and act antagonistically during pre-mRNA splicing. Developmental Dynamics 238:1595-1604, 2009. (c) 2009 Wiley-Liss, Inc.
Also flagged:Hepcidiniron-regulatory hormoneiron disorderscationpeptidescreatinine
Journal Article2009-06-01✓ 1 SnippetBansal SS, Halket JM, Fusova J, Bomford A, Simpson RJ, Vasavda N, Thein SL, Hider RC.
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Abstract)
…and suppressed inhemochromatosis.…
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Hepcidin is known to be a key systemic iron-regulatory hormone which has been demonstrated to be associated with a number of iron disorders. Hepcidin concentrations are increased in inflammation and suppressed in hemochromatosis. In view of the role of hepcidin in disease, its potential as a diagnostic tool in a clinical setting is evident. This study describes the development of a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) assay for the quantitative determination of hepcidin concentrations in clinical samples. A stable isotope labeled hepcidin was prepared as an internal standard and a standard quantity was added to urine samples. Extraction was performed with weak cation-exchange magnetic nanoparticles. The basic peptides were eluted from the magnetic nanoparticles using a matrix solution directly onto a target plate and analyzed by MALDI-TOF MS to determine the concentration of hepcidin. The assay was validated in charcoal stripped urine, and good recovery (70-80%) was obtained, as were limit of quantitation data (5 nmol/L), accuracy (RE <10%), precision (CV <21%), within -day repeatability (CV <13%) and between-day repeatability (CV <21%). Urine hepcidin levels were 10 nmol/mmol creatinine in healthy controls, with reduced levels in hereditary hemochromatosis (P < 0.000005) and elevated levels in inflammation (P < 0.0007). In summary a validated method has been developed for the determination of hepcidin concentrations in clinical samples.
Also flagged:dry eye syndromerheumatoid arthritisdry eyeRAandrogensystemic diseases
Journal Article2009-06-01✓ 1 SnippetAkpek EK, Klimava A, Thorne JE, Martin D, Lekhanont K, Ostrovsky A.
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…hemochromatosis…
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<h4>Purpose</h4>To evaluate the rate of Sjögren syndrome (SS) in a cohort of patients with dry eye syndrome.<h4>Methods</h4>Medical records of patients with a primary diagnosis of dry eye syndrome (International Classification of Diseases [ICD] code 375.15 or 370.33) were reviewed retrospectively. Patients who had 2 or more visits to a single dry eye center during a 2-year period (January 2004 to January 2006) were considered.<h4>Results</h4>Two hundred twenty patients with dry eye syndrome were identified. A total of 57 patients (25.9%) had an underlying rheumatic condition: 25 patients (11.4%) had rheumatoid arthritis and 24 (10.9%) had primary Sjögren syndrome (PSS). Majority of the patients with rheumatoid arthritis (96%) carried the diagnosis at the time of presentation. Of all patients with PSS, only 33.3% (8/24) carried the diagnosis at the time of presentation. Fifty percent (12/24) were diagnosed as a result of the initial evaluation. Among those, only 66.6% (8/12) tested SSA (anti-Ro antibodies) or SSB (anti-La antibodies) positive. One third of patients (4/12) tested only antinuclear antibody positive at a titer of <1/320 and required minor salivary gland biopsy for definitive diagnosis. Additional 16.7% (4/24), who were initially serologically negative, eventually underwent minor salivary gland biopsy and became diagnosed with SS.<h4>Conclusions</h4>PSS seems to be underdiagnosed in patients with dry eye syndrome and should be the focus of diagnostic evaluations. A minor salivary gland biopsy might be required for a definitive diagnosis in a significant proportion of the patients with SS.
Also flagged:ZEB2ETS1NF-kappaBEpithelial-to-mesenchymal transitionneurulationembryogenesis
Journal Article2009-06-01✓ 1 SnippetKatoh M, Katoh M.
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Abstract)
…was co-expressed withPOU3F2(BRN2) and POU3F3…
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Epithelial-to-mesenchymal transition (EMT) is defined as phenotypic change of epithelial cells into mesenchymal cells. EMT, allowing cellular dissociation from epithelial tissues, plays a key role in invasion and metastasis during carcinogenesis as well as in gastrulation and neurulation during embryogenesis. SNAI1/Snail, SNAI2/Slug, ZEB1/deltaEF1/ZFHX1A, ZEB2/SIP1/ZFHX1B, TWIST1/TWIST, and TWIST2/DERMO1 are representative EMT regulators. ZEB2 represses transcription of CDH1, CLDN4, CCND1, TERT, SFRP1, ALPL and miR-200b-200a-429 primary miRNA, and upregulates transcription of mesenchymal markers. ZEB2 is relatively highly expressed in brain corpus callosum and monocytes. ZEB2 is expressed in various types of human tumors, such as breast cancer, gastric cancer, and pancreatic cancer. TGFbeta, TNFalpha, IL1, AKT and hypoxia signals are involved in ZEB2 upregulation and EMT induction; however precise mechanisms of ZEB2 transcription remained unclear. Here, refined integrative genomic analyses of ZEB2 gene were carried out. ZEB2 was co-expressed with POU3F2 (BRN2) and POU3F3 (BRN1) in brain corpus callosum, spinal cord, and fetal brain, whereas ZEB2 was co-expressed with POU2F2 (OCT2) in monocytes. Ets-Smad-binding CGGAGAC motif, bHLH-binding site, and POU/OCT-binding site within proximal promoter region, and NF-kappaB-binding site within intron 2 were completely conserved in human ZEB2, chimpanzee ZEB2, cow ZEB2, mouse Zeb2, rat Zeb2, and chicken zeb2 genes. In addition, HIF1alpha-binding site within proximal promoter region was conserved in mammalian ZEB2 orthologs. Consensus binding site for Hedgehog effector GLI was not identified within or adjacent to the 7-kb regions of human ZEB2 gene. TGFbeta, TNFalpha, IL1, and hypoxia signals directly upregulate ZEB2 to induce EMT, growth arrest, and senescence, whereas Hedgehog signals indirectly upregulate ZEB2 via TGFbeta. Together these facts indicate that ZEB2, occupying the crossroads of inflammation, aging and carcinogenesis, is an important target for drug discovery.
Also flagged:head and neck squamous cell carcinomaHNSCCDNMT1PMAIP1PTPN1ERBB2
Journal Article2009-06-01✓ 3 SnippetsSethi S, Benninger MS, Lu M, Havard S, Worsham MJ.
In-Text Gene Mentions
Abstract)
…Saliva DNA was interrogated by a candidate gene panel comprising 82 genes using the multiplex ligation-dependent probe amplification assay.<h4>Results</h4>Eleven genes showed some predictive ability in identifying HNSCC cases from normal controls: PMAIP1, PTPN1, ERBB2, ABCC4, UTY, DNMT1, CDKN2B, CDKN2D, NFKB1, TP53, and DCC.…
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…NFKB1, TP53 andDCC.…
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…DCC…
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<h4>Background</h4>Head and neck squamous cell carcinoma (HNSCC) is a heterogeneous disease evolving through multistep carcinogenesis, one of the steps being genetic alterations. Noninvasive identification of HNSCC-specific genetic alterations using saliva would have immense potential in early diagnosis and screening, particularly among high-risk patients.<h4>Design</h4>In this exploratory study, a prospective cohort of 27 HNSCC and 10 healthy controls was examined to determine whether genetic alterations (losses and gains) in saliva DNA differentiated HNSCC patients from normal controls. Saliva DNA was interrogated by a candidate gene panel comprising 82 genes using the multiplex ligation-dependent probe amplification assay.<h4>Results</h4>Eleven genes showed some predictive ability in identifying HNSCC cases from normal controls: PMAIP1, PTPN1, ERBB2, ABCC4, UTY, DNMT1, CDKN2B, CDKN2D, NFKB1, TP53, and DCC. Statistical analysis using the Classification and Regression Tree (CART) identified 2 genes, PMAIP1 and PTPN1, which correctly discriminated all 27 HNSCC patients (100%) from normal controls. Results were validated using the leave-one-out validation approach.<h4>Conclusions</h4>Noninvasive high-throughput multiplex ligation-dependent probe amplification identified discrete gene signatures that differentiated HNSCC patients from normal controls providing proof-of-concept for noninvasive HNSCC detection.
Also flagged:chronicinterferonIFNAR1TYK2chronic hepatitis CInterferon-α
Journal Article2009-06-01No SnippetsWelzel TM, Morgan TR, Bonkovsky HL, Naishadham D, Pfeiffer RM, Wright EC, Hutchinson AA, Crenshaw AT, Bashirova A, Carrington M, Dotrang M, Sterling RK, Lindsay KL, Fontana RJ, Lee WM, Di Bisceglie AM, Ghany MG, Gretch DR, Chanock SJ, Chung RT, O'Brien TR, HALT-C Trial Group.
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<h4>Unlabelled</h4>Combination treatment with pegylated-interferon-alpha (PEG IFN-alpha) and ribavirin, the current recommended therapy for chronic hepatitis C virus (HCV) infection, results in a sustained virological response (SVR) in only about half of patients. Because genes involved in the interferon-alpha pathway may affect antiviral responses, we analyzed the relationship between variants in these genes and SVR among participants in the Hepatitis C Antiviral Long-Term treatment Against Cirrhosis (HALT-C) trial. Patients had advanced chronic hepatitis C that had previously failed to respond to interferon-based treatment. Participants were treated with peginterferon-alpha2a and ribavirin during the trial. Subjects with undetectable HCV RNA at week 72 were considered to have had an SVR. Subjects with detectable HCV RNA at week 20 were considered nonresponders. We used TaqMan assays to genotype 56 polymorphisms found in 13 genes in the interferon-alpha pathway. This analysis compares genotypes for participants with an SVR to nonresponders. The primary analysis was restricted to European American participants because a priori statistical power was low among the small number (n = 131) of African American patients. We used logistic regression to control the effect of other variables that are associated with treatment response. Among 581 European American patients, SVR was associated with IFNAR1 IVS1-22G (adjusted odds ratio, 0.57; P = 0.02); IFNAR2 Ex2-33C (adjusted odds ratio, 2.09; P = 0.02); JAK1 IVS22+112T (adjusted odds ratio, 1.66; P = 0.04); and ADAR Ex9+14A (adjusted odds ratio, 1.67; P = 0.03). For the TYK2-2256A promoter region variant, a borderline association was present among European American participants (OR, 1.51; P = 0.05) and a strong relationship among African American patients; all 10 with SVR who were genotyped for TYK2 -2256 carried the A variant compared with 68 of 120 (57%) nonresponders (P = 0.006).<h4>Conclusion</h4>Genetic polymorphisms in the interferon-alpha pathway may affect responses to antiviral therapy of chronic hepatitis C.
Also flagged:synthesistetrahydrofuranLewis acidacetic anhydridestyrenestatine
Journal Article2009-06-01No SnippetsGhosh AK, Shurrush K, Kulkarni S.
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An asymmetric synthesis of anti-aldol segments via a nonaldol route is described. The strategy involves a highly diastereoselective synthesis of functionalized tetrahydrofuran derivatives from optically active 4-phenylbutyrolactone. Treatment of the tetrahydrofuran derivatives with a Lewis acid and acetic anhydride provided the corresponding ring-opened styrene derivatives. Oxidative cleavage of the styrene derivatives provided access to the anti-aldol segments. The utility of this methodology was demonstrated by the synthesis of statine derivatives and pancreatic lipase inhibitor, (-)-tetrahydrolipstatin.
Also flagged:aniondigestionlumenbicarbonatecarbonatecarbonic anhydrases
Journal Article2009-06-01No SnippetsLinser PJ, Smith KE, Seron TJ, Neira Oviedo M.
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Mosquito larvae use a digestive strategy that is relatively rare in nature. The anterior half of the larval mosquito midgut has a luminal pH that ranges between 10.5 and 11.5. Most other organisms, both large and small, initiate digestion in an acid medium. The relative uniqueness of the highly alkaline digestive strategy has been a long-standing research focus in larval lepidopterans. More recently, the disease vector potential of mosquitoes has fueled specific interest in larval mosquito biology and the alkaline digestive environment in the midgut. The probable principle anion influencing the highly alkaline gut lumen is bicarbonate/carbonate. Bicarbonate/carbonate is regulated at least in part by the activity of carbonic anhydrases. Hence, we have focused attention on the carbonic anhydrases of the mosquito larva. Anopheles gambiae, the major malaria mosquito of Africa, is an organism with a published genome which has facilitated molecular analyses of the 12 carbonic anhydrase genes annotated for this mosquito. Microarray expression analyses, tissue-specific quantitative RT-PCR, and antibody localization have been used to generate a picture of carbonic anhydrase distribution in the larval mosquito. Cytoplasmic, GPI-linked extracellular membrane-bound and soluble extracellular carbonic anhydrases have been located in the midgut and hindgut. The distribution of the enzymes is consistent with an anion regulatory system in which carbonic anhydrases provide a continuous source of bicarbonate/carbonate from the intracellular compartments of certain epithelial cells to the ectoperitrophic space between the epithelial cells and the acellular membrane separating the food bolus from the gut cells and finally into the gut lumen. Carbonic anhydrase in specialized cells of the hindgut (rectum) probably plays a final role in excretion of bicarbonate/carbonate into the aquatic environment of the larva. Detection and characterization of classic anion exchangers of the SLC4A family in the midgut has been problematic. The distribution of carbonic anhydrases in the system may obviate the requirement for such transporters, making the system more dependent on simple carbon dioxide diffusion and ionization via the activity of the enzyme.
Also flagged:GJB2GJB6hearingHard-of-HearingdeafnessCongenital deafness
Journal Article2009-06-01✓ 1 SnippetPalmer CG, Martinez A, Fox M, Zhou J, Shapiro N, Sininger Y, Grody WW, Schimmenti LA.
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…hemochromatosis…
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There are limited data on the impact of incorporating genetic counseling and testing into the newborn hearing screening process. We report on results from a prospective, longitudinal study to determine the impact of genetic counseling and GJB2/GJB6 genetic testing on parental knowledge, attitudes, and beliefs about genetic testing. One hundred thirty culturally hearing parents of 93 deaf or hard-of-hearing children ages 0-3 years primarily identified through newborn hearing screening received pre- and post-test genetic counseling for GJB2 and GJB6. Parents completed questionnaires following pre-test counseling, and 1- and 6-month post-test result disclosure. Results indicate that following pre-test counseling all parents perceived benefits to genetic testing. While parents who received positive results continued to perceive benefits from testing, perceived benefit declined among parents who received inconclusive or negative results. Parents did not perceive genetic testing as harmful following pre-test counseling or receipt of test results. Parents who received positive test results performed better in understanding recurrence and causation of their child's deafness and indicated greater interest in prenatal genetic testing than those who received inconclusive or negative test results. Parents felt that pediatricians and audiologists should inform parents of genetic testing availability; however, there was no consensus on timing of this discussion. Thus culturally hearing parents do not perceive genetic testing of their deaf or hard-of-hearing infants/toddlers as harmful; they feel that primary care providers should discuss genetic testing with them; and positive genetic test results with genetic counseling give rise to better understanding and perceived benefit than negative or inconclusive results.
Also flagged:depressionanxietycancerfolatedihydropyrimidine dehydrogenaseDPYD
Journal Article2009-06-01No SnippetsSprangers MA, Sloan JA, Veenhoven R, Cleeland CS, Halyard MY, Abertnethy AP, Baas F, Barsevick AM, Bartels M, Boomsma DI, Chauhan C, Dueck AC, Frost MH, Hall P, Klepstad P, Martin NG, Miaskowski C, Mosing M, Movsas B, Van Noorden CJ, Patrick DL, Pedersen NL, Ropka ME, Shi Q, Shinozaki G, Singh JA, Yang P, Zwinderman AH.
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To our knowledge, no comprehensive, interdisciplinary initiatives have been taken to examine the role of genetic variants on patient-reported quality-of-life outcomes. The overall objective of this paper is to describe the establishment of an international and interdisciplinary consortium, the GENEQOL Consortium, which intends to investigate the genetic disposition of patient-reported quality-of-life outcomes. We have identified five primary patient-reported quality-of-life outcomes as initial targets: negative psychological affect, positive psychological affect, self-rated physical health, pain, and fatigue. The first tangible objective of the GENEQOL Consortium is to develop a list of potential biological pathways, genes and genetic variants involved in these quality-of-life outcomes, by reviewing current genetic knowledge. The second objective is to design a research agenda to investigate and validate those genes and genetic variants of patient-reported quality-of-life outcomes, by creating large datasets. During its first meeting, the Consortium has discussed draft summary documents addressing these questions for each patient-reported quality-of-life outcome. A summary of the primary pathways and robust findings of the genetic variants involved is presented here. The research agenda outlines possible research objectives and approaches to examine these and new quality-of-life domains. Intriguing questions arising from this endeavor are discussed. Insight into the genetic versus environmental components of patient-reported quality-of-life outcomes will ultimately allow us to explore new pathways for improving patient care. If we can identify patients who are susceptible to poor quality of life, we will be able to better target specific clinical interventions to enhance their quality of life and treatment outcomes.
<h4>Background</h4>Hypertension and associated disorders are major risk factors for cardiovascular disease. The Lyon hypertensive rat (LH) is a genetically hypertensive strain that exhibits spontaneous and salt-sensitive hypertension, exaggerated proteinuria, high body weight, hyperlipidemia, and elevated insulin-to-glucose ratio. Previous genetic mapping identified quantitative trait loci (QTLs) influencing blood pressure (BP) on rat chromosome 13 (RNO13) in several models of hypertension.<h4>Methods</h4>To study the effects of a single chromosome on the mapped traits, we generated consomic strains by substituting LH RNO13 with that of the normotensive Brown Norway (BN) strain (LH-13BN) and reciprocal consomics by substituting a BN RNO13 with that of LH (BN-13LH). These reciprocal consomic strains, as well as the two parental strains were characterized for BP, metabolic and morphological parameters.<h4>Results</h4>Compared with LH parents, LH-13BN rats showed decreased mean BP (up to -24 mmHg on 2% NaCl in the drinking water), urine proteins and lipids, and increased body weight. Differences between BN-13LH and BN rats were much smaller than those observed between LH-13BN and LH rats, demonstrating the effects of the highly resistant BN genome background. Plasma renin activity was not affected by the substitution of RNO13, despite the significant BP differences.<h4>Conclusion</h4>The present work demonstrates that RNO13 is a determinant of BP, proteinuria, and plasma lipids in the LH rat. The distinct phenotypic differences between the consomic LH-13BN and the LH make it a powerful model to determine genes and pathways leading to these risk factors for cardiovascular and renal disease.
A new strategy is described for functionalizing the omega-terminal end of polymers synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization that provides spatially controlled bioconjugation sites. Traditional methods for preparing omega-functional polymers require the reduction of the RAFT chain-transfer agent to yield secondary or tertiary thiols of low reactivity or the synthesis of novel chain-transfer agents that contain reactive groups. As an additional strategy, N-substituted maleimido monomers have been used in a modified block polymerization to add a single maleimido unit onto the RAFT polymer with nearly quantitative efficiency. Unique reactive groups contained in the N-substituent are thereby added to the omega-terminal end of the polymer and are subsequently available for conjugation reactions. This technique has been demonstrated using N-(2-aminoethyl)maleimide trifluoroacetate to introduce a single primary amine to the omega-terminus of poly(dimethylaminoethyl methacrylate) and poly(N-isopropyl acrylamide) and to a specialized block copolymer for siRNA delivery. Evidence for retention of functional RAFT endgroups is provided by synthesis results where chain-extended polyDMAEMA (M(n) = 10 600 g/mol, M(w)/M(n) = 1.14) was used as a macro chain transfer agent for the polymerization of styrene, yielding a diblock polymer of low polydispersity (M(n) = 20 300 g/mol, M(w)/M(n) = 1.11). It is thus also possible to construct diblock copolymers with a bioconjugation site precisely located at the junction between the two blocks. The chain-extended polymers are functionalized with an amine-reactive fluorescent dye or folic acid at conjugation efficiencies of 86 and 94%, respectively. The versatile chain-extension technique described here offers unique opportunities for the synthesis of well-defined polymeric conjugates to molecules of biological and targeting interest.
…The HD mutation is an expanded CAG trinucleotide repeat in the HD gene that is translated into a polyglutamine (polyQ) repeat in the huntingtin (Htt) protein [2].…
Huntington's disease (HD) is an inherited, progressive neurological disorder caused by a CAG/polyglutamine repeat expansion, for which there is no effective disease modifying therapy. In recent years, transcriptional dysregulation has emerged as a pathogenic process that appears early in disease progression. Administration of histone deacetylase (HDAC) inhibitors such as suberoylanilide hydroxamic acid (SAHA) have consistently shown therapeutic potential in models of HD, at least partly through increasing the association of acetylated histones with down-regulated genes and by correcting mRNA abnormalities. The HDAC enzyme through which SAHA mediates its beneficial effects in the R6/2 mouse model of HD is not known. Therefore, we have embarked on a series of genetic studies to uncover the HDAC target that is relevant to therapeutic development for HD. HDAC7 is of interest in this context because SAHA has been shown to decrease HDAC7 expression in cell culture systems in addition to inhibiting enzyme activity. After confirming that expression levels of Hdac7 are decreased in the brains of wild type and R6/2 mice after SAHA administration, we performed a genetic cross to determine whether genetic reduction of Hdac7 would alleviate phenotypes in the R6/2 mice. We found no improvement in a number of physiological or behavioral phenotypes. Similarly, the dysregulated expression levels of a number of genes of interest were not improved suggesting that reduction in Hdac7 does not alleviate the R6/2 HD-related transcriptional dysregulation. Therefore, we conclude that the beneficial effects of HDAC inhibitors are not predominantly mediated through the inhibition of HDAC7.
Individuals differ in the extent to which they emphasize feelings of pleasure or displeasure in their verbal reports of emotional experience, termed valence focus (VF). Two event-contingent, experience-sampling studies examined the relationship between VF and sensitivity to pleasant and unpleasant social cues. It was predicted, and found, that individuals with greater VF (i.e., who emphasized feelings of pleasure/displeasure in reports of emotional experience) demonstrated greater self-esteem lability (i.e., larger changes in self-esteem) to pleasant and unpleasant information contained in social interactions than did those lower in VF. These effects held even after statistically controlling for possible confounding variables (neuroticism, affect intensity). Implications for understanding the psychological impact of valenced interpersonal events are discussed.
Also flagged:squamous cell carcinomas of cervixpersistent infectionsquamous cell carcinomas of the uterine cervixSCCs of the head and neckcarcinomasand
Journal Article2009-06-01✓ 3 SnippetsWilting SM, Smeets SJ, Snijders PJ, van Wieringen WN, van de Wiel MA, Meijer GA, Ylstra B, Leemans CR, Meijer CJ, Brakenhoff RH, Braakhuis BJ, Steenbergen RD.
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…The SRO on chromosome 13 encompasses the PCDH17 gene and a cluster of five identical loci all of which are predicted to encode proline-rich proteins that contain several dopamine D4 receptor signatures.…
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…13 encompasses thePCDH17gene and a…
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…one known gene,PCDH17, a member of…
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<h4>Background</h4>It is well known that a persistent infection with high-risk human papillomavirus (hrHPV) is causally involved in the development of squamous cell carcinomas of the uterine cervix (CxSCCs) and a subset of SCCs of the head and neck (HNSCCs). The latter differ from hrHPV-negative HNSCCs at the clinical and molecular level.<h4>Methods</h4>To determine whether hrHPV-associated SCCs arising from different organs have specific chromosomal alterations in common, we compared genome-wide chromosomal profiles of 10 CxSCCs (all hrHPV-positive) with 12 hrHPV-positive HNSCCs and 30 hrHPV-negative HNSCCs. Potential organ-specific alterations and alterations shared by SCCs in general were investigated as well.<h4>Results</h4>Unsupervised hierarchical clustering resulted in one mainly hrHPV-positive and one mainly hrHPV-negative cluster. Interestingly, loss at 13q and gain at 20q were frequent in HPV-positive carcinomas of both origins, but uncommon in hrHPV-negative HNSCCs, indicating that these alterations are associated with hrHPV-mediated carcinogenesis. Within the group of hrHPV-positive carcinomas, HNSCCs more frequently showed gains of multiple regions at 8q whereas CxSCCs more often showed loss at 17p. Finally, gains at 3q24-29 and losses at 11q22.3-25 were frequent (>50%) in all sample groups.<h4>Conclusion</h4>In this study hrHPV-specific, organ-specific, and pan-SCC chromosomal alterations were identified. The existence of hrHPV-specific alterations in SCCs of different anatomical origin, suggests that these alterations are crucial for hrHPV-mediated carcinogenesis.
Also flagged:AVPACTHAVPR1Banxiety disordersbehavioralnucleotide
Journal Article2009-06-01✓ 1 SnippetCagliani R, Fumagalli M, Pozzoli U, Riva S, Cereda M, Comi GP, Pattini L, Bresolin N, Sironi M.
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…GLRX, CHRNA4, SULT1C2,PRDX6, H2AFX, ODC1, MT2A,…
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<h4>Background</h4>The vasopressin receptor type 1b (AVPR1B) is mainly expressed by pituitary corticotropes and it mediates the stimulatory effects of AVP on ACTH release; common AVPR1B haplotypes have been involved in mood and anxiety disorders in humans, while rodents lacking a functional receptor gene display behavioral defects and altered stress responses.<h4>Results</h4>Here we have analyzed the two exons of the gene and the data we present suggest that AVPR1B has been subjected to natural selection in humans. In particular, analysis of exon 2 strongly suggests the action of balancing selection in African populations and Europeans: the region displays high nucleotide diversity, an excess of intermediate-frequency alleles, a higher level of within-species diversity compared to interspecific divergence and a genealogy with common haplotypes separated by deep branches. This relatively unambiguous situation coexists with unusual features across exon 1, raising the possibility that a nonsynonymous variant (Gly191Arg) in this region has been subjected to directional selection.<h4>Conclusion</h4>Although the underlying selective pressure(s) remains to be identified, we consider this to be among the first documented examples of a gene involved in mood disorders and subjected to natural selection in humans; this observation might add support to the long-debated idea that depression/low mood might have played an adaptive role during human evolution.
Also flagged:selenocysteineamino acidtranslationalcysteineseleniumSe-deficiency diseases
Journal Article2009-06-01✓ 1 SnippetCastellano S, Andrés AM, Bosch E, Bayes M, Guigó R, Clark AG.
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Selenocysteine (Sec), the 21st amino acid, is incorporated into proteins through the recoding of a termination codon, an inefficient translational process mediated by a complex molecular machinery. Sec is a rare amino acid in extant proteins, chemically similar to cysteine (Cys), found in homologous position to Cys of nonselenoprotein families. Selenoproteins account for the dependence of vertebrates on environmental selenium (Se) and have an important role in several Se-deficiency diseases. Selenoproteins are poorly characterized enzymes and reports on the functional exchangeability of Sec with Cys are limited and controversial. Whether the unique role of Sec in some selenoenzymes illustrates the broader contribution of Se to protein function is unknown (Gromer S, Johansson L, Bauer H, Arscott LD, Rauch S, Ballou DP, Williams CH Jr, Schirmer RH, Arnér ES. 2003. Active sites of thioredoxin reductases: why selenoproteins? Proc Natl Acad Sci USA. 100:12618-12623). Here, we address this question from an evolutionary perspective by the simultaneous identification of the patterns of divergence in almost half a billion years of vertebrate evolution and diversity within the human lineage for the full complement of enzymatic Sec residues in these proteomes. We complete this analysis with data for the homologous Cys residues in the same genomes. Our results indicate concerted purifying selection across Sec and Cys sites in all selenoproteomes, consistent with a unique role of Sec in protein function, low exchangeability, and an unknown degree of functional divergence with Cys homologs. The distinct biochemical properties of Sec, rather than the geographical distribution of Se, global O(2) levels or Sec metabolic cost, appear to play a major role in driving adaptive changes in vertebrate selenoproteomes. A better understanding of the selenoproteomes and neutral evolutionary patterns in other taxa will be necessary to fully assess the generality of this conclusion.
Also flagged:GABRA2psychiatric disordersalcohol dependenceaggressionnucleotidebehavioral
Journal Article2009-06-01✓ 1 SnippetDick DM, Latendresse SJ, Lansford JE, Budde JP, Goate A, Dodge KA, Pettit GS, Bates JE.
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<h4>Context</h4>As we identify genes involved in psychiatric disorders, the next step will be to study how the risk associated with susceptibility genes manifests across development and in conjunction with the environment. We describe analyses aimed at characterizing the pathway of risk associated with GABRA2, a gene previously associated with adult alcohol dependence, in a community sample of children followed longitudinally from childhood through young adulthood.<h4>Objective</h4>To test for an association between GABRA2 and trajectories of externalizing behavior from adolescence to young adulthood and for moderation of genetic effects by parental monitoring.<h4>Design</h4>Data were analyzed from the Child Development Project, with yearly assessments conducted since that time. A saliva sample was collected for DNA at the 2006 follow-up, with a 93% response rate in the target sample. Growth mixture modeling was conducted using Mplus to identify trajectories of externalizing behavior and to test for effects of GABRA2 sequence variants and parental monitoring.<h4>Setting</h4>Nashville and Knoxville, Tennessee, and Bloomington, Indiana.<h4>Participants</h4>A community-based sample of families enrolled at 3 sites as children entered kindergarten in 1987 and 1988. Analyses for the white subset of the sample (n = 378) are reported here.<h4>Main outcome measures</h4>Parental monitoring measured at 11 years of age; Child Behavior Checklist youth reports of externalizing behavior at ages 12, 14, 15, 16, 17, 19, 20, 21, and 22 years.<h4>Results</h4>Two classes of externalizing behavior emerged: a stable high externalizing class and a moderate decreasing externalizing behavior class. The GABRA2 gene was associated with class membership, with subjects who showed persistent elevated trajectories of externalizing behavior more likely to carry the genotype previously associated with increased risk of adult alcohol dependence. A significant interaction with parental monitoring emerged; the association of GABRA2 with externalizing trajectories diminished with high levels of parental monitoring.<h4>Conclusions</h4>These analyses underscore the importance of studying genetic effects across development and of identifying environmental factors that moderate risk.
Also flagged:polyglutamine diseasesHuntington diseaseHDpolyglutaminepotassiumnitrogen
Journal Article2009-06-01✓ 1 SnippetNekooki-Machida Y, Kurosawa M, Nukina N, Ito K, Oda T, Tanaka M.
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A hallmark of polyglutamine diseases, including Huntington disease (HD), is the formation of beta-sheet-rich aggregates, called amyloid, of causative proteins with expanded polyglutamines. However, it has remained unclear whether the polyglutamine amyloid is a direct cause or simply a secondary manifestation of the pathology. Here we show that huntingtin-exon1 (thtt) with expanded polyglutamines remarkably misfolds into distinct amyloid conformations under different temperatures, such as 4 degrees C and 37 degrees C. The 4 degrees C amyloid has loop/turn structures together with mostly beta-sheets, including exposed polyglutamines, whereas the 37 degrees C amyloid has more extended and buried beta-sheets. By developing a method to efficiently introduce amyloid into mammalian cells, we found that the formation of the 4 degrees C amyloid led to substantial toxicity, whereas the toxic effects of the 37 degrees C amyloid were very small. Importantly, thtt amyloids in different brain regions of HD mice also had distinct conformations. The thermolabile thtt amyloid with loop/turn structures in the striatum showed higher toxicity, whereas the rigid thtt amyloid with more extended beta-sheets in the hippocampus and cerebellum had only mild toxic effects. These studies show that the thtt protein with expanded polyglutamines can misfold into distinct amyloid conformations and, depending on the conformations, the amyloids can be either toxic or nontoxic. Thus, the amyloid conformation of thtt may be a critical determinant of cytotoxicity in HD.
Also flagged:oxygenmetabolismgene expressioninfertilitygonadotrophincytoplasmic
Journal Article2009-06-01✓ 1 SnippetCombelles CM, Gupta S, Agarwal A.
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In the efforts aimed at improving the quality of in-vitro-matured human oocytes, the dynamic balance and roles of pro-/antioxidants merit further consideration. In-vitro maturation (IVM) is emerging as a popular technology at the forefront of fertility treatment and preservation. However, standard in-vitro culture conditions exert oxidative stress or an imbalance between oxidants and antioxidants. Reactive oxygen species (ROS) are oxygen-derived molecules formed as intermediary products of cellular metabolism. By acting as powerful oxidants, ROS can oxidatively modify any molecule, resulting in structural and functional alterations. ROS are neutralized by an elaborate defence system consisting of enzymatic and nonenzymatic antioxidants. This review captures the inherent and external factors that may modulate the oxidative stress status of oocytes. It discusses the suspected impacts of oxidative stress on the gamut of events associated with IVM, including prematuration arrest, meiotic progression, chromosomal segregation, cytoskeletal architecture and gene expression. In-vivo and in-vitro strategies that may overcome the potential influences of oxidative stress on oocyte IVM are presented. Future studies profiling the oxidative stress status of the oocyte may permit not only the formulation of a superior IVM medium that maintains an adequate pro-/antioxidant balance, but also the identification of predictors of oocyte quality.
Also flagged:pathogenesisasthmainnervationserotoninmast cell degranulationmast cell activation
Journal Article2009-06-01No SnippetsCyphert JM, Kovarova M, Allen IC, Hartney JM, Murphy DL, Wess J, Koller BH.
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Mast cells are important sentinels guarding the interface between the environment and the body: a breach in the integrity of this interface can lead to the release of a plethora of mediators that engage the foreign agent, recruit leukocytes, and initiate adaptive physiological changes in the organism. While these capabilities make mast cells critical players in immune defense, it also makes them important contributors to the pathogenesis of diseases such as asthma. Mast cell mediators induce dramatic changes in smooth muscle physiology, and the expression of receptors for these factors by smooth muscle suggests that they act directly to initiate constriction. Contrary to this view, we show herein that mast cell-mediated bronchoconstriction is observed only in animals with intact innervation of the lung and that serotonin release alone is required for this action. While ablation of sensory neurons does not limit bronchoconstriction, constriction after Ag challenge is absent in mice in which the cholinergic pathways are compromised. Linking mast cell function to the cholinergic system likely provides an important means of modulating the function of these resident immune cells to physiology of the lung, but may also provide a safeguard against life-threatening anaphylaxis during mast cell degranulation.
Also flagged:IL-2CTLsIFN-gammaTNF-alphaGranzyme Bsecretion
Journal Article2009-06-01No SnippetsWalch M, Rampini SK, Stoeckli I, Latinovic-Golic S, Dumrese C, Sundstrom H, Vogetseder A, Marino J, Glauser DL, van den Broek M, Sander P, Groscurth P, Ziegler U.
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Regulation of cytotoxic effector molecule expression in human CTLs after viral or bacterial activation is poorly understood. By using human autologous dendritic cells (DCs) to prime T lymphocytes, we found perforin only highly up-regulated in virus- (HSV-1, vaccinia virus) but not in intracellular bacteria- (Listeria innocua, Listeria monocytogenes, Mycobacterium tuberculosis, Chlamydophila pneumoniae) activated CTLs. In contrast, larger quantities of IFN-gamma and TNF-alpha were produced in Listeria-stimulated cultures. Granzyme B and granulysin were similarly up-regulated by all tested viruses and intracellular bacteria. DCs infected with HSV-1 showed enhanced surface expression of the costimulatory molecule CD252 (CD134L) compared with Listeria-infected DC and induced enhanced secretion of IL-2. Adding blocking CD134 or neutralizing IL-2 Abs during T cell activation reduced the HSV-dependent up-regulation of perforin. These data indicate a distinct CTL effector function in response to intracellular pathogens triggered via differing endogenous IL-2 production upon costimulation through CD252.
Also flagged:Toxic hepatitisacute liver failureceftriaxonecephalosporinchildhood infectionsaspartate aminotransferase
Journal Article2009-06-01✓ 1 SnippetPeker E, Cagan E, Dogan M.
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…hemochromatosis…
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Toxic hepatitis or drug-induced liver injury encompasses a spectrum of clinical disease ranging from mild biochemical abnormalities to acute liver failure. The advantages of a long half-life, wide spectrum, high tissue penetration rate, and a good safety profile, make ceftriaxone, a third-generation cephalosporin, a frequent choice in the treatment of childhood infections. Previous studies have reported a few cases of high aspartate aminotransferase and alanine aminotransferase levels, along with three cases of hepatitis caused by ceftriaxone. Here, we report a case of drug-induced toxic hepatitis in a patient who was treated with ceftriaxone for acute tonsillitis.
…Huntington's disease (HD) is caused by a polyglutamine repeat in the protein huntingtin (Htt) with mutant Htt (mHtt) expressed throughout the body and similarly in all brain regions.…
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…the protein huntingtin (Htt) with mutant Htt…
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…(Htt) with mutantHtt(mHtt) expressed throughout…
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…Htt…
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Huntington's disease (HD) is caused by a polyglutamine repeat in the protein huntingtin (Htt) with mutant Htt (mHtt) expressed throughout the body and similarly in all brain regions. Yet, HD neuropathology is largely restricted to the corpus striatum. We report that the small guanine nucleotide-binding protein Rhes, which is localized very selectively to the striatum, binds physiologically to mHtt. Using cultured cells, we found Rhes induces sumoylation of mHtt, which leads to cytotoxicity. Thus, Rhes-mHtt interactions can account for the localized neuropathology of HD.
<h4>Background</h4>Because of its nutrients and anabolic hormones, cow's milk may promote height growth, which in turn has been related to breast cancer risk. We prospectively investigated associations between dairy intakes and height growth.<h4>Methods</h4>A cohort of 5,101 girls from throughout the United States completed annual surveys (1996-2001, 2003), providing height, weight, and past-year diet. At baseline, all were premenarchal, ages 9 years and above, with no serious medical conditions. We studied three outcomes: annual height growth, peak growth velocity, and adult height. Multivariate models estimated the effects of milk, cheese, yogurt, and energy on subsequent growth, adjusted for race/ethnicity, age, prior height, and body mass index. Other models studied fats and proteins.<h4>Results</h4>Premenarchal girls who drank >3 servings per day of milk grew 0.11 in. (P = 0.02) more the following year than girls consuming <1 serving per day. Yogurt (+0.13 in./cup; P = 0.02), but not cheese or total calories, predicted height growth. In a separate model, dairy protein (+0.034 in./10 g; P < 0.001) predicted height growth. Larger peak velocities were seen among girls reporting, at baseline, more milk (>3 glasses per day versus <1; +0.14 in., P = 0.01), more yogurt (+0.17 in./cup, P = 0.02), and, in a separate model, more dairy protein (+0.039 in./10 g; P = 0.003). Baseline milk and dairy protein predicted taller adults. Dairy protein was more important than dairy fat, for all outcomes. Nondairy animal protein and vegetable protein were never significant, nor were nondairy animal fat and vegetable fat.<h4>Conclusion</h4>Of the foods/nutrients studied, dairy protein had the strongest association with height growth. These findings suggest that a factor in the nonlipid phase of milk, but not protein itself, has growth-promoting action in girls.
Extracellular gradients of secreted guidance factors are known to guide axon pathfinding and neuronal migration. These factors are likely to bind to cell surfaces or extracellular matrix, but whether and how they may act in bound gradients remains mostly unclear. In this study, we have developed a new technique for rapid production of stable microscopic gradients of substrate-bound proteins by covalent bonding of the proteins with an epoxy-coated glass substrate while they are diffusing in an agarose gel. Using this method, we found that bound gradients of netrin-1 and brain-derived neurotrophic factor (BDNF) can polarize the initiation and turning of axons in cultured hippocampal neurons. Furthermore, bound BDNF gradient caused attractive and repulsive polarizing response on gradients of low- and high-average density of BDNF, respectively. This novel bidirectional response to BDNF depended on the basal level of cAMP in the neuron. Finally, our data showed that the neuron's attractive response to bound BDNF gradient depended on the absolute difference rather than the relative difference in the BDNF density across the neuron, with a minimal effective difference of 1-2 BDNF molecule/mum(2) on the substrate surface. Thus, substrate-bound guidance factors are highly effective in polarizing axon initiation and growth, and the diffusive printing technique is useful for studying neuronal responses induced by bound protein gradients.
Also flagged:liver fibrosishepatitis C infectionsyphilisHIV infectionacute hepatitis Cinfections
Journal Article2009-06-01✓ 1 SnippetOsinusi A, Kleiner D, Wood B, Polis M, Masur H, Kottilil S.
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…hemochromatosis…
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We report the first reported case of a 61-year-old MSM who was diagnosed with syphilis, primary HIV infection, and acute hepatitis C (HCV) within the same time period who rapidly developed significant liver fibrosis within 6 months of acquisition of both infections. It has been well described that individuals with primary HIV infection have an increase in activated CD8+ T cells, which causes a state of immune activation as was evident in this patient. Acquisition of HCV during this time could have further skewed this response resulting in massive hepatocyte destruction, inflammation, and subsequent liver fibrosis. Recent literature suggest that MSM with primary HIV infection have higher rates of acquisition of HCV than other HIV-positive cohorts and HCV acquisition can occur very soon after acquiring HIV. This case of rapid hepatic fibrosis progression coupled with the increasing incidence of HCV in individuals with primary HIV infection demonstrates a need for this phenomenon to be studied more extensively.
Also flagged:Prion proteinPrPmetabolismubiquitin ligasecytosolNeurodegeneration
Journal Article2009-06-01✓ 1 SnippetChakrabarti O, Hegde RS.
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…Htt…
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The pathways leading from aberrant Prion protein (PrP) metabolism to neurodegeneration are poorly understood. Some familial PrP mutants generate increased (Ctm)PrP, a transmembrane isoform associated with disease. In other disease situations, a potentially toxic cytosolic form (termed cyPrP) might be produced. However, the mechanisms by which (Ctm)PrP or cyPrP cause selective neuronal dysfunction are unknown. Here, we show that both (Ctm)PrP and cyPrP can interact with and disrupt the function of Mahogunin (Mgrn), a cytosolic ubiquitin ligase whose loss causes spongiform neurodegeneration. Cultured cells and transgenic mice expressing either (Ctm)PrP-producing mutants or cyPrP partially phenocopy Mgrn depletion, displaying aberrant lysosomal morphology and loss of Mgrn in selected brain regions. These effects were rescued by either Mgrn overexpression, competition for PrP-binding sites, or prevention of cytosolic PrP exposure. Thus, transient or partial exposure of PrP to the cytosol leads to inappropriate Mgrn sequestration that contributes to neuronal dysfunction and disease.
Also flagged:chromatinHMGN1HMG14HMGN2HMG17nucleosome-
Journal Article2009-06-01✓ 1 SnippetRattner BP, Yusufzai T, Kadonaga JT.
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…HMGN4…
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The high-mobility group N (HMGN) proteins are abundant nonhistone chromosomal proteins that bind specifically to nucleosomes at two high-affinity sites. Here we report that purified recombinant human HMGN1 (HMG14) and HMGN2 (HMG17) potently repress ATP-dependent chromatin remodeling by four different molecular motor proteins. In contrast, mutant HMGN proteins with double Ser-to-Glu mutations in their nucleosome-binding domains are unable to inhibit chromatin remodeling. The HMGN-mediated repression of chromatin remodeling is reversible and dynamic. With the ACF chromatin remodeling factor, HMGN2 does not directly inhibit the ATPase activity but rather appears to reduce the affinity of the factor to chromatin. These findings suggest that HMGN proteins serve as a counterbalance to the action of the many ATP-dependent chromatin remodeling activities in the nucleus.
Also flagged:T-type calcium channelT-type voltage-gated Ca(2+) channelsepilepsysleepdisturbancescardiac arrhythmias
Journal Article2009-06-01No SnippetsBelardetti F, Tringham E, Eduljee C, Jiang X, Dong H, Hendricson A, Shimizu Y, Janke DL, Parker D, Mezeyova J, Khawaja A, Pajouhesh H, Fraser RA, Arneric SP, Snutch TP.
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T-type voltage-gated Ca(2+) channels have been implicated in contributing to a broad variety of human disorders, including pain, epilepsy, sleep disturbances, cardiac arrhythmias, and certain types of cancer. However, potent and selective T-type Ca(2+) channel modulators are not yet available for clinical use. This may in part be due to their unique biophysical properties that have delayed the development of high-throughput screening (HTS) assays for identifying blockers. One notable challenge is that at the normal resting membrane potential (V(m)) of cell lines commonly utilized for drug screening purposes, T-type Ca(2+) channels are largely inactivated and thus cannot be supported by typical formats of functional HTS assays to both evoke and quantify the Ca(2+) channel signal. Here we describe a simple method that can successfully support a fluorescence-based functional assay for compounds that modulate T-type Ca(2+)channels. The assay functions by exploiting the pore-forming properties of gramicidin to control the cellular V(m) in advance of T-type Ca(2+) channel activation. Using selected ionic conditions in the presence of gramicidin, T-type Ca(2+) channels are converted from the unavailable, inactivated state to the available, resting state, where they can be subsequently activated by application of extracellular K(+). The fidelity of the assay has been pharmacologically characterized with sample T-type Ca(2+) channel blockers whose potency has been determined by conventional manual patch-clamp techniques. This method has the potential for applications in high-throughput fluorometric imaging plate reader (FLIPR(R), Molecular Devices, Sunnyvale, CA) formats with cell lines expressing either recombinant or endogenous T-type Ca(2+) channels.
Also flagged:EphB receptorsDendritic spinessynapsesF-actinFAKdendritic spine
Journal Article2009-06-01✓ 1 SnippetShi Y, Pontrello CG, DeFea KA, Reichardt LF, Ethell IM.
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Text
…DCC receptor…
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Dendritic spines are the postsynaptic sites of most excitatory synapses in the brain and are highly enriched in polymerized F-actin, which drives the formation and maintenance of mature dendritic spines and synapses. We propose that suppressing the activity of the actin-severing protein cofilin plays an important role in the stabilization of mature dendritic spines, and is accomplished through an EphB receptor-focal adhesion kinase (FAK) pathway. Our studies revealed that Cre-mediated knock-out of loxP-flanked fak prompted the reversion of mature dendritic spines to an immature filopodial-like phenotype in primary hippocampal cultures. The effects of FAK depletion on dendritic spine number, length, and morphology were rescued by the overexpression of the constitutively active FAK(Y397E), but not FAK(Y397F), indicating the significance of FAK activation by phosphorylation on tyrosine 397. Our studies demonstrate that FAK acts downstream of EphB receptors in hippocampal neurons and EphB2-FAK signaling controls the stability of mature dendritic spines by promoting cofilin phosphorylation, thereby inhibiting cofilin activity. While constitutively active nonphosphorylatable cofilin(S3A) induced an immature spine profile, phosphomimetic cofilin(S3D) restored mature spine morphology in neurons with disrupted EphB activity or lacking FAK. Further, we found that EphB-mediated regulation of cofilin activity at least partially depends on the activation of Rho-associated kinase (ROCK) and LIMK-1. These findings indicate that EphB2-mediated dendritic spine stabilization relies, in part, on the ability of FAK to activate the RhoA-ROCK-LIMK-1 pathway, which functions to suppress cofilin activity and inhibit cofilin-mediated dendritic spine remodeling.
Also flagged:Pulmonary arterial hypertensionendothelial dysfunctionvasoconstrictionbone morphogenetic protein type II receptorextracellularglycoprotein
Pulmonary arterial hypertension (PAH) is caused by functional and structural changes in the pulmonary vasculature, leading to increased pulmonary vascular resistance. The process of pulmonary vascular remodeling is accompanied by endothelial dysfunction, activation of fibroblasts and smooth muscle cells, crosstalk between cells within the vascular wall, and recruitment of circulating progenitor cells. Recent findings have reestablished the role of chronic vasoconstriction in the remodeling process. Although the pathology of PAH in the lung is well known, this article is concerned with the cellular and molecular processes involved. In particular, we focus on the role of the Rho family guanosine triphosphatases in endothelial function and vasoconstriction. The crosstalk between endothelium and vascular smooth muscle is explored in the context of mutations in the bone morphogenetic protein type II receptor, alterations in angiopoietin-1/TIE2 signaling, and the serotonin pathway. We also review the role of voltage-gated K(+) channels and transient receptor potential channels in the regulation of cytosolic [Ca(2+)] and [K(+)], vasoconstriction, proliferation, and cell survival. We highlight the importance of the extracellular matrix as an active regulator of cell behavior and phenotype and evaluate the contribution of the glycoprotein tenascin-c as a key mediator of smooth muscle cell growth and survival. Finally, we discuss the origins of a cell type critical to the process of pulmonary vascular remodeling, the myofibroblast, and review the evidence supporting a contribution for the involvement of endothelial-mesenchymal transition and recruitment of circulating mesenchymal progenitor cells.
Also flagged:Pulmonary arterial hypertensionHPAHIPAHtransforming growth factor-betahereditary hemorrhagic telangiectasiaBMPR2
Journal Article2009-06-01No SnippetsMachado RD, Eickelberg O, Elliott CG, Geraci MW, Hanaoka M, Loyd JE, Newman JH, Phillips JA, Soubrier F, Trembath RC, Chung WK.
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Pulmonary arterial hypertension (PAH) is a rare disorder that may be hereditable (HPAH), idiopathic (IPAH), or associated with either drug-toxin exposures or other medical conditions. Familial cases have long been recognized and are usually due to mutations in the bone morphogenetic protein receptor type 2 gene (BMPR2), or, much less commonly, 2 other members of the transforming growth factor-beta superfamily, activin-like kinase-type 1 (ALK1) and endoglin (ENG), which are associated with hereditary hemorrhagic telangiectasia. In addition, approximately 20% of patients with IPAH carry mutations in BMPR2. We provide a summary of BMPR2 mutations associated with HPAH, most of which are unique to each family and are presumed to result in loss of function. We review the finding of missense variants and variants of unknown significance in BMPR2 in IPAH/HPAH, fenfluramine exposure, and PAH associated with congenital heart disease. Clinical testing for BMPR2 mutations is available and may be offered to HPAH and IPAH patients but should be preceded by genetic counseling, since lifetime penetrance is only 10% to 20%, and there are currently no known effective preventative measures. Identification of a familial mutation can be valuable in reproductive planning and identifying family members who are not mutation carriers and thus will not require lifelong surveillance. With advances in genomic technology and with international collaborative efforts, genome-wide association studies will be conducted to identify additional genes for HPAH, genetic modifiers for BMPR2 penetrance and genetic susceptibility to IPAH. In addition, collaborative studies of BMPR2 mutation carriers should enable identification of environmental modifiers, biomarkers for disease development and progression, and surrogate markers for efficacy end points in clinical drug development, thereby providing an invaluable resource for trials of PAH prevention.
Also flagged:5-hydroxytryptamine transporternicotineserotoninsecretionreuptakeSerotonin transporter
Journal Article2009-06-01✓ 3 SnippetsChu SL, Xiao D, Wang C, Jing H.
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Abstract)
…Serotonin transporter (5-HTT) is the most important protein, as it adjusts the serotonin concentration in the synaptic cleft.…
Abstract)
…Serotonin transporter (5-HTT) is the most…
Abstract)
…region of the5-HTTgene, named 5-hydroxytryptamin…
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<h4>Background</h4>Tobacco use is the major risk factor for numerous health problems. However, only 5% of smokers can successfully quit without therapy owing to the highly addictive properties of nicotine. The serotoninergic system may be involved in smoking behavior because nicotine increases brain serotonin secretion, nicotine withdrawal decreases serotonin levels, and a selective serotonin reuptake inhibitor antagonizes the response to nicotine withdrawal. Serotonin transporter (5-HTT) is the most important protein, as it adjusts the serotonin concentration in the synaptic cleft. There is a polymorphism in the upstream regulatory region of the 5-HTT gene, named 5-hydroxytryptamine transporter gene-linked polymorphic region (5-HTTLPR). Compared with the L allele, the S allele of the polymorphism is associated with decreased transcription efficiency of the 5-HTT gene. In this study, we investigated the relationship between this gene polymorphism and smoking behavior in Chinese males.<h4>Methods</h4>Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was performed to find 5-HTTLPR gene polymorphisms in 144 smokers and 135 age-matched healthy non-smokers. A questionnaire was completed in all recruited subjects.<h4>Results</h4>The proportion of L/L (15.3% vs 5.2%) and S/L (50.0% vs 33.3%) genotypes was significantly higher in the smokers than that in the non-smokers (chi(2) = 21.9; P < 0.01). The odds ratio (OR) adjusted by age, education, effects of family members and friends who smoke, and alcohol intake was 2.9 (95% CI 1.78 +/- 4.80). In smokers, the number of cigarettes/day (L/L vs S/L vs S/S: 28 +/- 12 vs 20 +/- 8 vs 16 +/- 6, chi(2) = 18.5, P < 0.01), smoking index (L/L vs S/L vs S/S: 561 +/- 446 vs 393 +/- 341 vs 237 +/- 201, chi(2) = 12.5, P < 0.01) and score on the Fagerström test for nicotine dependence (FTND) (L/L vs S/L vs S/S: 7.8 +/- 1.6 vs 6.2 +/- 2.5 vs 3.5 +/- 2.1, chi(2) = 48.3, P < 0.01) were significantly higher in smokers with an L/L or S/L genotype than that in the smokers with the S/S genotype. There were no significant differences in the proportion of starting smoking before 20 years old (P = 0.219) and those who succeeded in quitting smoking for more than 1 month (P = 0.456) between individuals with different 5-HTTLPR genotypes in smokers.<h4>Conclusions</h4>5-HTTLPR polymorphism may be associated with susceptibility to cigarette smoking in Chinese males. The proportion of the L/L and S/L genotype in smokers was higher than that in non-smokers. In smokers, the level of nicotine dependence and resultant cigarettes consumption may be much higher in individuals with an L/L or S/L genotype than those with the S/S genotype.
Also flagged:Breast cancerERPRHer2estrogen receptorprogesterone receptor
Journal Article2009-06-01No SnippetsOnitilo AA, Engel JM, Greenlee RT, Mukesh BN.
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<h4>Objective</h4>To compare the clinicopathologic features and survival in the four breast cancer subtypes defined by immunohistochemistry (IHC) expression of estrogen receptor (ER) or progesterone receptor (PR) and human epidermal growth factor receptor 2 (Her2): ER/PR+, Her2+; ER/PR+, Her2-; ER/PR-, Her2+; and ER/PR-, Her2-.<h4>Methods</h4>A 7-year retrospective study of 1134 invasive breast cancer subjects. Clinical and pathologic features and survival of the four subtypes were compared.<h4>Results</h4>Using ER/PR+ and Her2- as a reference, ER/PR-, Her2- had the worst overall survival (hazard ratio, 1.8; 95% confidence interval [CI], 1.06-3.2) and the worst disease-free survival (hazard ratio, 1.5; 95% CI, 0.8-3.0). In ER/PR+, Her2-, chemotherapy conferred significant overall and disease-free survival advantages. Subtype comparison revealed statistically significant differences in outcomes.<h4>Conclusion</h4>The triple negative subtype has the worst overall and disease free survival. Efforts should be directed at standardization of current testing methods and development of more reliable and reproducible testing.
…Although the serotonin neurotransmitter system is closely associated with depression and the effects of nicotine, the authors are not aware of any studies that have evaluated the possible role of individual differences in serotonin transporter (5-HTT) genotype and depressive symptoms as moderators of the effects of NRT on SWM.…
Abstract)
…in serotonin transporter (5-HTT) genotype and depressive…
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Smokers may use nicotine to self-medicate for situation-specific or person-specific cognitive or affective deficits. Although evidence suggests that nicotine replacement therapy (NRT), relative to placebo, enhances spatial working memory (SWM) in smoking-abstinent smokers with schizophrenia, the extent to which NRT may be helpful in attenuating abstinence-related SWM in other groups with deficits in SWM is unknown. Depressive symptoms are associated with both tobacco smoking and deficits in SWM. Previous studies have found that smoking abstinence increases depressive affect and depression-related hemispheric asymmetries in brain activation. Although the serotonin neurotransmitter system is closely associated with depression and the effects of nicotine, the authors are not aware of any studies that have evaluated the possible role of individual differences in serotonin transporter (5-HTT) genotype and depressive symptoms as moderators of the effects of NRT on SWM. Thus, the current study assessed the effects of NRT (nicotine patch) on SWM in relation to: (1) depressive traits and (2) 5-HTT genotype. Smoking-deprived habitual smokers (N = 64) completed the dot recall test of SWM during counterbalanced and double-blind nicotine and placebo testing sessions. There was a marginal overall effect of NRT on SWM. More importantly, NRT enhanced SWM in 5-HTT short allele carriers, relative to those with two long alleles, and this enhancement in short-allele carriers was greater for individuals with higher levels of depressive symptoms.
Also flagged:Hereditary hemochromatosisankle arthritisHHcysteinetyrosineamino acid
Journal Article2009-06-01✓ 5 SnippetsCarlsson A.
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Discussion)
…Lunn et al. (2005) found 2 out of 116 patients who had undergone primary hip replacement to be C282Y homozygotes—a figure that is similar to the prevalence in the general population of Ireland. Curiously enough, substantially more patients—10 of 101 patients—who underwent revision of their hip were C282Y homozygotes. In a large population study, Adams et al. (2005) only found self-reported arthritis to be more common in males who were homozygous for H63D than in participants without HFE mutations. Walker et al. (2006) demonstrated an association between genotype and interleukin 1 receptor antagonist (IL1RN) levels in patients with HH and joint pain. Axford et al. (1991) described an increased incidence of hip involvement, and Rollot et al. (2005) suggested that osteonecrosis of the femoral head may be one expression of HH.…
Introduction)
…Thehemochromatosisgene was identified…
Introduction)
…2,851 patients withhemochromatosisshowed that patients…
Also flagged:lysinetranslationalSUMOylationnucleuspsychiatric disordersneurodegenerative disorders
Journal Article2009-06-01No SnippetsAnderson DB, Wilkinson KA, Henley JM.
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Small ubiquitin-related modifier (SUMO) proteins are approximately 11 kDa proteins that can be covalently conjugated to lysine residues in defined target proteins. The resultant post-translational modification, SUMOylation, is vital for the viability of mammalian cells and regulates, among other things, a range of essential nuclear processes. It has become increasingly apparent in recent years that SUMOylation also serves multiple functions outside the nucleus and that it plays a critical role in the regulation of neuronal integrity and synaptic function. In particular, dysfunction of the SUMOylation pathway has been implicated in the molecular and cellular dysfunction associated with neurodegenerative and psychiatric disorders. Here, we outline current knowledge of the SUMO pathway and discuss the growing evidence for its involvement in multiple neurodegenerative disorders, with a view to highlighting the potential of the SUMO pathway as a putative drug target.
Also flagged:calciuminfectionhydroxyapatiteglutaraldehydeformaldehydeethanol
Journal Article2009-06-01No SnippetsWright GA, Faught JM, Olin JM.
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The objective of this work was to demonstrate that the New Zealand White (NZW) rabbit intramuscular model can be used for detecting calcification in bioprosthetic tissue and to compare the calcification in the rabbit to that of native human valves. The rabbit model was compared with the commonly used Sprague-Dawley rat subcutaneous model. Eighteen rabbits and 18 rats were used to assess calcification in bioprosthetic tissue over time (7, 14, 30, and 90 d). The explanted rabbit and rat tissue discs were measured for calcium by using atomic absorption and Raman spectroscopy. Calcium deposits on the human valve explants were assessed by using Raman spectroscopy. The results showed that the NZW rabbit model is robust for detecting calcification in a shorter duration (14 d), with less infection complications, more space to implant tissue groups (thereby reducing animal use numbers), and a more metabolically and mechanically dynamic environment than the rat subcutaneous model . The human explanted valves and rabbit explanted tissue both showed Raman peaks at 960 cm(-1) which is representative of hydroxyapatite. Hydroxyapatite is the final calcium and phosphate species in the calcification of bioprosthetic heart valves and rabbit intramuscular implants. The NZW rabbit intramuscular model is an effective model for assessing calcification in bioprosthetic tissue.
Also flagged:cardiovascular diseaseagingoxygenfibrinogenIGF1insulin
Journal Article2009-06-01✓ 1 SnippetVidean EN, Heward CB, Chowdhury K, Plummer J, Su Y, Cutler RG.
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…PRDX6…
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In the oxidative stress hypothesis of aging, the aging process is the result of cumulative damage by reactive oxygen species. Humans and chimpanzees are remarkably similar; but humans live twice as long as chimpanzees and therefore are believed to age at a slower rate. The purpose of this study was to compare biomarkers for cardiovascular disease, oxidative stress, and aging between male chimpanzees and humans. Compared with men, male chimpanzees were at increased risk for cardiovascular disease because of their significantly higher levels of fibrinogen, IGF1, insulin, lipoprotein a, and large high-density lipoproteins. Chimpanzees showed increased oxidative stress, measured as significantly higher levels of 5-hydroxymethyl-2-deoxyuridine and 8-iso-prostaglandin F(2alpha), a higher peroxidizability index, and higher levels of the prooxidants ceruloplasmin and copper. In addition, chimpanzees had decreased levels of antioxidants, including alpha- and beta-carotene, beta-cryptoxanthin, lycopene, and tocopherols, as well as decreased levels of the cardiovascular protection factors albumin and bilirubin. As predicted by the oxidative stress hypothesis of aging, male chimpanzees exhibit higher levels of oxidative stress and a much higher risk for cardiovascular disease, particularly cardiomyopathy, compared with men of equivalent age. Given these results, we hypothesize that the longer lifespan of humans is at least in part the result of greater antioxidant capacity and lower risk of cardiovascular disease associated with lower oxidative stress.
Also flagged:SiliconemembraneheparinclottingcoagulationQuadrox-D
Journal Article2009-06-01✓ 1 SnippetSievert AN, Shackelford AG, McCall MM.
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Text
…ATIII…
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Extracorporeal life support (ECLS) is a procedure used to support the failing heart and/or lungs via a heart lung machine. Over 145 institutions perform this practice in the United States with more than 24,000 ECLS cases recorded. While many articles are published each year on common perfusion practice, little information is shared on emerging technologies in ECLS and common practices among perfusionists and ECLS specialists. This article presents our 2006 ECLS survey results and discusses emerging technologies and management topics new to the ECLS arena. ECLS specialists were asked to participate in an online survey. Two hundred twenty-two ECLS specialists responded. This survey suggests positive displacement roller pumps are still the leading pump used for ECLS 122/188 (64.9%). Silicone membrane oxygenators are used by responders 75% of the time for long-term use, while hollow fiber membrane oxygenators are used 44%. Forty-five percent of responders are using heparin or biocoated circuits exclusively, while 14.6% restrict their use to specific subpopulations. The most common coating is heparin coating (67.9%). Activated clotting time (ACT) management is still standard of care for coagulation monitoring (98%), while partial thromboplastin time (PTT) follows at 71.7%. The interquartile range for ACTs is 160-220 seconds and 160-200 seconds with active bleeding. This article suggests ECLS specialists are beginning to incorporate different technology into their practice, such as centrifugal pumps with hollow fiber oxygenators and coated-circuits.
Also flagged:CA125cancerOCovarian cancertumorpost-translational modifications
Journal Article2009-06-01No SnippetsSasaroli D, Coukos G, Scholler N.
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Ovarian cancer (OC) is the fourth leading cause of cancer deaths among women in the United States, despite its relatively low incidence of 50 per 100,000. Even though advances in therapy have been made, the OC fatality-to-case ratio remains exceedingly high, due to the lack of accurate tools to diagnose early-stage disease when cure is still possible. The most studied marker for OC, CA125, is only expressed by 50-60% of patients with early stage disease. Large efforts have been deployed to identify novel serum markers, yet no single marker has emerged as a serious competitor for CA125. Various groups are investing in combination approaches to increase the diagnostic value of existing markers, but many markers may still lie in under-explored areas of ovarian cancer biology, such as tumor vasculature environment and post-translational modifications (glycomics).
Also flagged:Ubiquilin 1conformational disordersneurodegenerative diseasescancerchaperonesamino acids
Journal Article2009-06-01No SnippetsZhang C, Saunders AJ.
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The process of refolding or degrading misfolded proteins is the most important function of protein quality control (PQC) system. An imbalance between the capacity of PQC system and the quantity and severity of misfolded proteins may result in protein aggregate accumulation, which can ultimately contribute to a class of diseases referred to as conformational disorders. Numerous lines of evidence suggest that Ubiquilin 1 is an important component in PQC. Ubiquilin 1 has been indicated to be involved in the pathophysiology of neurodegenerative diseases and cancer. Here we review the evidence that Ubiquilin 1 is an important component of the PQC system and also review the role of Ubiquilin 1 in human diseases.
Also flagged:autismserotonin transporterserotonin5-hydroxytryptamine5-HT transporterautism-spectrum disorders
Journal Article2009-06-01✓ 2 SnippetsVeenstra-Vanderweele J, Jessen TN, Thompson BJ, Carter M, Prasad HC, Steiner JA, Sutcliffe JS, Blakely RD.
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Abstract)
…The 5-HT transporter gene (HTT, SERT, SLC6A4) has received considerable attention as a potential risk locus for autism-spectrum disorders, as well as disorders with overlapping symptoms, including obsessive-compulsive disorder (OCD).…
Abstract)
…5-HT transporter gene (HTT, SERT, SLC6A4 )…
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Alterations in peripheral and central indices of serotonin (5-hydroxytryptamine, 5-HT) production, storage and signaling have long been associated with autism. The 5-HT transporter gene (HTT, SERT, SLC6A4) has received considerable attention as a potential risk locus for autism-spectrum disorders, as well as disorders with overlapping symptoms, including obsessive-compulsive disorder (OCD). Here, we review our efforts to characterize rare, nonsynonymous polymorphisms in SERT derived from multiplex pedigrees carrying diagnoses of autism and OCD and present the initial stages of our effort to model one of these variants, Gly56Ala, in vivo. We generated a targeting vector to produce the Gly56Ala substitution in the Slc6a4 locus by homologous recombination. Following removal of a neomycin resistance selection cassette, animals exhibiting germline transmission of the Ala56 variant were bred to establish a breeding colony on a 129S6 background, suitable for initial evaluation of biochemical, physiological and behavioral alterations relative to SERT Gly56 (wild-type) animals. SERT Ala56 mice were achieved and exhibit a normal pattern of transmission. The initial growth and gross morphology of these animals is comparable to wildtype littermate controls. The SERT Ala56 variant can be propagated in 129S6 mice without apparent disruption of fertility and growth. We discuss both the opportunities and challenges that await the physiological/behavioral analysis of Gly56Ala transgenic mice, with particular reference to modeling autism-associated traits.
Also flagged:oxygenphosphorescencetetranaphthoporphyrinsmacrocycleMetalloporphyrinsdendrimers
Journal Article2009-06-01No SnippetsLebedev AY, Cheprakov AV, Sakadzić S, Boas DA, Wilson DF, Vinogradov SA.
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Oxygen levels in biological systems can be measured by the phosphorescence quenching method using probes with controllable quenching parameters and defined biodistributions. We describe a general approach to the construction of phosphorescent nanosensors with tunable spectral characteristics, variable degrees of quenching, and a high selectivity for oxygen. The probes are based on bright phosphorescent Pt and Pd complexes of porphyrins and symmetrically pi-extended porphyrins (tetrabenzoporphyrins and tetranaphthoporphyrins). pi-Extension of the core macrocycle allows tuning of the spectral parameters of the probes in order to meet the requirements of a particular imaging application (e.g., oxygen tomography versus planar microscopic imaging). Metalloporphyrins are encapsulated into poly(arylglycine) dendrimers, which fold in aqueous environments and create diffusion barriers for oxygen, making it possible to regulate the sensitivity and the dynamic range of the method. The periphery of the dendrimers is modified with poly(ethylene glycol) residues, which enhance the probe's solubility, diminish toxicity, and help prevent interactions of the probes with the biological environment. The probe's parameters were measured under physiological conditions and shown to be unaffected by the presence of biomacromolecules. The performance of the probes was demonstrated in applications, including in vivo microscopy of vascular pO(2) in the rat brain.
Journal Article2009-06-01No SnippetsMason SB, Lai X, Bacallao RL, Blazer-Yost BL, Gattone VH, Wang KC, Witzmann FA.
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Autosomal Dominant Polycystic Kidney Disease (ADPKD) is characterized by the development of numerous fluid-filled cysts in the kidneys of patients. We recently published our description of the proteome of renal cyst fluid in ADPKD. As a follow-up experiment, we hypothesized that the protein-bound subfraction consists of molecules of mechanistic or diagnostic interest in ADPKD. Using a manual biomarker enrichment kit, we have identified 44 distinct proteins in human cyst fluid.