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Find video protocols related to scientific articles indexed in Pubmed.
Whole genome sequencing to understand the genetic architecture of common gene expression and biomarker phenotypes.
Hum. Mol. Genet.
PUBLISHED: 11-06-2014
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Initial results from sequencing studies suggest that there are relatively few low frequency (<5%) variants associated with large effects on common phenotypes. We performed low pass whole genome sequencing in 680 individuals from the InCHIANTI study to test two primary hypotheses: i) that sequencing would detect single low frequency - large effect variants that explained similar amounts of phenotypic variance as single common variants, and ii) that some common variant associations could be explained by low frequency variants. We tested two sets of disease-related common phenotypes for which we had statistical power to detect large numbers of common variant - common phenotype associations - 11,132 cis-gene expression traits in 450 individuals and 93 circulating biomarkers in all 680 individuals. From a total of 11,657,229 high quality variants of which 6,129,221 and 5,528,008 were common and low frequency (<5%) respectively, low frequency - large effect associations comprised 7% of detectable cis-gene expression traits (89 of 1,314 cis-eQTLs at P<1x10(-06) (FDR ?5%)) and 1 of 8 biomarker associations at P<8x10(-10). Very few (30 of 1,232; 2%) common variant associations were fully explained by low frequency variants. Our data show that whole genome sequencing can identify low frequency variants undetected by genotyping based approaches when sample sizes are sufficiently large to detect substantial numbers of common variant associations, and that common variant associations are rarely explained by single low frequency variants of large effect.
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Precompetitive achievement goals, stress appraisals, emotions, and coping among athletes.
J Sport Exerc Psychol
PUBLISHED: 10-31-2014
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Grounded in Lazarus's (1991, 1999, 2000) cognitive-motivational-relational theory of emotions, we tested a model of achievement goals, stress appraisals, emotions, and coping. We predicted that precompetitive achievement goals would be associated with appraisals, appraisals with emotions, and emotions with coping in our model. The mediating effects of emotions among the overall sample of 827 athletes and two stratified random subsamples were also explored. The results of this study support our proposed model in the overall sample and the stratified subsamples. Further, emotion mediated the relationship between appraisal and coping. Mediation analyses revealed that there were indirect effects of pleasant and unpleasant emotions, which indicates the importance of examining multiple emotions to reveal a more accurate representation of the overall stress process. Our findings indicate that both appraisals and emotions are just as important in shaping coping.
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Guidelines for the diagnosis, prevention and management of implantable cardiac electronic device infection. Report of a joint Working Party project on behalf of the British Society for Antimicrobial Chemotherapy (BSAC, host organization), British Heart Rhythm Society (B
J. Antimicrob. Chemother.
PUBLISHED: 10-31-2014
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Infections related to implantable cardiac electronic devices (ICEDs), including pacemakers, implantable cardiac defibrillators and cardiac resynchronization therapy devices, are increasing in incidence in the USA and are likely to increase in the UK, because more devices are being implanted. These devices have both intravascular and extravascular components and infection can involve the generator, device leads and native cardiac structures or various combinations. ICED infections can be life-threatening, particularly when associated with endocardial infection, and all-cause mortality of up to 35% has been reported. Like infective endocarditis, ICED infections can be difficult to diagnose and manage. This guideline aims to (i) improve the quality of care provided to patients with ICEDs, (ii) provide an educational resource for all relevant healthcare professionals, (iii) encourage a multidisciplinary approach to ICED infection management, (iv) promote a standardized approach to the diagnosis, management, surveillance and prevention of ICED infection through pragmatic evidence-rated recommendations, and (v) advise on future research projects/audit. The guideline is intended to assist in the clinical care of patients with suspected or confirmed ICED infection in the UK, to inform local infection prevention and treatment policies and guidelines and to be used in the development of educational and training material by the relevant professional societies. The questions covered by the guideline are presented at the beginning of each section.
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Novel chromogenic aminopeptidase substrates for the detection and identification of clinically important microorganisms.
Bioorg. Med. Chem.
PUBLISHED: 08-12-2014
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A series of amino acid derivatives 8-10, 42 and 43 have been prepared as chromogenic enzyme substrates in order to detect aminopeptidase activity in clinically important Gram-negative and Gram-positive bacteria. Enzymatic hydrolysis liberates the amino acid moiety and either a 4-aminophenol or a 4-dialkylaminoaniline derivative which undergoes oxidative coupling with 1-naphthol or a substituted 1-naphthol giving an indophenol dye. Substrates and 1-naphthols were incorporated into an agar-based culture medium and this allowed growth of intensely coloured bacterial colonies based on hydrolysis by specific enzymes. Red/pink coloured colonies were produced by the substrates 8-10 and blue coloured colonies were formed by the substrates 42 and 43. The L-alanyl aminopeptidase substrates 8 targeted L-alanyl aminopeptidase activity and gave coloured colonies with a range of Gram-negative bacteria. Substrates 9 targeted ?-alanyl aminopeptidase activity and generated coloured colonies with selected Gram-negative species including Pseudomonas aeruginosa. Three substrates for L-pyroglutamyl acid aminopeptidase (10a, 10c and 43) were hydrolysed by enterococci and Streptococcus pyogenes to generate coloured colonies. Two yeasts were also included in the study, but they did not produce coloured colonies with any of the substrates examined.
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Genetic evidence for a normal-weight "metabolically obese" phenotype linking insulin resistance, hypertension, coronary artery disease, and type 2 diabetes.
Diabetes
PUBLISHED: 07-21-2014
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The mechanisms that predispose to hypertension, coronary artery disease (CAD), and type 2 diabetes (T2D) in individuals of normal weight are poorly understood. In contrast, in monogenic primary lipodystrophy-a reduction in subcutaneous adipose tissue-it is clear that it is adipose dysfunction that causes severe insulin resistance (IR), hypertension, CAD, and T2D. We aimed to test the hypothesis that common alleles associated with IR also influence the wider clinical and biochemical profile of monogenic IR. We selected 19 common genetic variants associated with fasting insulin-based measures of IR. We used hierarchical clustering and results from genome-wide association studies of eight nondisease outcomes of monogenic IR to group these variants. We analyzed genetic risk scores against disease outcomes, including 12,171 T2D cases, 40,365 CAD cases, and 69,828 individuals with blood pressure measurements. Hierarchical clustering identified 11 variants associated with a metabolic profile consistent with a common, subtle form of lipodystrophy. A genetic risk score consisting of these 11 IR risk alleles was associated with higher triglycerides (? = 0.018; P = 4 × 10(-29)), lower HDL cholesterol (? = -0.020; P = 7 × 10(-37)), greater hepatic steatosis (? = 0.021; P = 3 × 10(-4)), higher alanine transaminase (? = 0.002; P = 3 × 10(-5)), lower sex-hormone-binding globulin (? = -0.010; P = 9 × 10(-13)), and lower adiponectin (? = -0.015; P = 2 × 10(-26)). The same risk alleles were associated with lower BMI (per-allele ? = -0.008; P = 7 × 10(-8)) and increased visceral-to-subcutaneous adipose tissue ratio (? = -0.015; P = 6 × 10(-7)). Individuals carrying ?17 fasting insulin-raising alleles (5.5% population) were slimmer (0.30 kg/m(2)) but at increased risk of T2D (odds ratio [OR] 1.46; per-allele P = 5 × 10(-13)), CAD (OR 1.12; per-allele P = 1 × 10(-5)), and increased blood pressure (systolic and diastolic blood pressure of 1.21 mmHg [per-allele P = 2 × 10(-5)] and 0.67 mmHg [per-allele P = 2 × 10(-4)], respectively) compared with individuals carrying ?9 risk alleles (5.5% population). Our results provide genetic evidence for a link between the three diseases of the "metabolic syndrome" and point to reduced subcutaneous adiposity as a central mechanism.
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Molecular epidemiology of NDM-1-producing Enterobacteriaceae and Acinetobacter baumannii isolates from Pakistan.
Antimicrob. Agents Chemother.
PUBLISHED: 06-30-2014
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The molecular epidemiology of 66 NDM-producing isolates from 2 Pakistani hospitals was investigated, with their genetic relatedness determined using repetitive sequence-based PCR (Rep-PCR). PCR-based replicon typing and screening for antibiotic resistance genes encoding carbapenemases, other ?-lactamases, and 16S methylases were also performed. Rep-PCR suggested a clonal spread of Enterobacter cloacae and Escherichia coli. A number of plasmid replicon types were identified, with the incompatibility A/C group (IncA/C) being the most common (78%). 16S methylase-encoding genes were coharbored in 81% of NDM-producing Enterobacteriaceae.
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Non cystic fibrosis bronchiectasis: A longitudinal retrospective observational cohort study of Pseudomonas persistence and resistance.
Respir Med
PUBLISHED: 06-25-2014
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The hallmark of non-cystic fibrosis bronchiectasis is recurrent bronchial infection, yet there are significant gaps in our understanding of pathogen persistence, resistance and exacerbation frequencies. Pseudomonas aeruginosa is a key pathogen thought to be a marker of disease severity and progression, yet little is known if the infection risk is seen in those with milder disease or if there is any potential for eradication. These data are important in determining risk stratification and follow up.
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Parent-of-origin-specific allelic associations among 106 genomic loci for age at menarche.
John R B Perry, Felix Day, Cathy E Elks, Patrick Sulem, Deborah J Thompson, Teresa Ferreira, Chunyan He, Daniel I Chasman, Tonu Esko, Gudmar Thorleifsson, Eva Albrecht, Wei Q Ang, Tanguy Corre, Diana L Cousminer, Bjarke Feenstra, Nora Franceschini, Andrea Ganna, Andrew D Johnson, Sanela Kjellqvist, Kathryn L Lunetta, George McMahon, Ilja M Nolte, Lavinia Paternoster, Eleonora Porcu, Albert V Smith, Lisette Stolk, Alexander Teumer, Natalia Tšernikova, Emmi Tikkanen, Sheila Ulivi, Erin K Wagner, Najaf Amin, Laura J Bierut, Enda M Byrne, Jouke-Jan Hottenga, Daniel L Koller, Massimo Mangino, Tune H Pers, Laura M Yerges-Armstrong, Jing Hua Zhao, Irene L Andrulis, Hoda Anton-Culver, Femke Atsma, Stefania Bandinelli, Matthias W Beckmann, Javier Benitez, Carl Blomqvist, Stig E Bojesen, Manjeet K Bolla, Bernardo Bonanni, Hiltrud Brauch, Hermann Brenner, Julie E Buring, Jenny Chang-Claude, Stephen Chanock, Jinhui Chen, Georgia Chenevix-Trench, J Margriet Collée, Fergus J Couch, David Couper, Andrea D Coviello, Angela Cox, Kamila Czene, Adamo Pio D'adamo, George Davey Smith, Immaculata De Vivo, Ellen W Demerath, Joe Dennis, Peter Devilee, Aida K Dieffenbach, Alison M Dunning, Gudny Eiriksdottir, Johan G Eriksson, Peter A Fasching, Luigi Ferrucci, Dieter Flesch-Janys, Henrik Flyger, Tatiana Foroud, Lude Franke, Melissa E Garcia, Montserrat Garcia-Closas, Frank Geller, Eco E J de Geus, Graham G Giles, Daniel F Gudbjartsson, Vilmundur Gudnason, Pascal Guénel, Suiqun Guo, Per Hall, Ute Hamann, Robin Haring, Catharina A Hartman, Andrew C Heath, Albert Hofman, Maartje J Hooning, John L Hopper, Frank B Hu, David J Hunter, David Karasik, Douglas P Kiel, Julia A Knight, Veli-Matti Kosma, Zoltan Kutalik, Sandra Lai, Diether Lambrechts, Annika Lindblom, Reedik Mägi, Patrik K Magnusson, Arto Mannermaa, Nicholas G Martin, Gisli Masson, Patrick F McArdle, Wendy L McArdle, Mads Melbye, Kyriaki Michailidou, Evelin Mihailov, Lili Milani, Roger L Milne, Heli Nevanlinna, Patrick Neven, Ellen A Nohr, Albertine J Oldehinkel, Ben A Oostra, Aarno Palotie, Munro Peacock, Nancy L Pedersen, Paolo Peterlongo, Julian Peto, Paul D P Pharoah, Dirkje S Postma, Anneli Pouta, Katri Pylkäs, Paolo Radice, Susan Ring, Fernando Rivadeneira, Antonietta Robino, Lynda M Rose, Anja Rudolph, Veikko Salomaa, Serena Sanna, David Schlessinger, Marjanka K Schmidt, Mellissa C Southey, Ulla Sovio, Meir J Stampfer, Doris Stöckl, Anna M Storniolo, Nicholas J Timpson, Jonathan Tyrer, Jenny A Visser, Peter Vollenweider, Henry Völzke, Gérard Waeber, Melanie Waldenberger, Henri Wallaschofski, Qin Wang, Gonneke Willemsen, Robert Winqvist, Bruce H R Wolffenbuttel, Margaret J Wright, , Dorret I Boomsma, Michael J Econs, Kay-Tee Khaw, Ruth J F Loos, Mark I McCarthy, Grant W Montgomery, John P Rice, Elizabeth A Streeten, Unnur Thorsteinsdottir, Cornelia M van Duijn, Behrooz Z Alizadeh, Sven Bergmann, Eric Boerwinkle, Heather A Boyd, Laura Crisponi, Paolo Gasparini, Christian Gieger, Tamara B Harris, Erik Ingelsson, Marjo-Riitta Järvelin, Peter Kraft, Debbie Lawlor, Andres Metspalu, Craig E Pennell, Paul M Ridker, Harold Snieder, Thorkild I A Sørensen, Tim D Spector, David P Strachan, André G Uitterlinden, Nicholas J Wareham, Elisabeth Widén, Marek Zygmunt, Anna Murray, Douglas F Easton, Kari Stefansson, Joanne M Murabito, Ken K Ong.
Nature
PUBLISHED: 05-30-2014
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Age at menarche is a marker of timing of puberty in females. It varies widely between individuals, is a heritable trait and is associated with risks for obesity, type 2 diabetes, cardiovascular disease, breast cancer and all-cause mortality. Studies of rare human disorders of puberty and animal models point to a complex hypothalamic-pituitary-hormonal regulation, but the mechanisms that determine pubertal timing and underlie its links to disease risk remain unclear. Here, using genome-wide and custom-genotyping arrays in up to 182,416 women of European descent from 57 studies, we found robust evidence (P?
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Bacteria detection based on the evolution of enzyme-generated volatile organic compounds: determination of Listeria monocytogenes in milk samples.
Anal. Chim. Acta
PUBLISHED: 05-28-2014
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The rapid detection of Listeria monocytogenes contamination in food is essential to prevent food-borne illness in humans. The aim of this study was to differentiate non-contaminated milk from milk contaminated with L. monocytogenes using enzyme substrates coupled with the analysis of volatile organic compounds (VOCs). The method is based on the activity of ?-glucosidase and hippuricase enzymes and the detection of a specific VOC i.e. 2-nitrophenol and 3-fluoroaniline, respectively. VOCs were extracted, separated and detected by headspace-solid phase microextraction coupled to gas chromatography-mass spectrometry (HS-SPME GC-MS). This approach required the inclusion of the selective agent's cycloheximide, nalidixic acid and acriflavine HCl in the growth medium to inhibit interfering bacteria. The VOCs were liberated by L. monocytogenes provided that samples contained at least 1-1.5×10(2) CFU ml(-1) of milk prior to overnight incubation. This approach shows potential for future development as a rapid method for the detection of L. monocytogenes contaminated milk.
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Megakaryocytes maintain homeostatic quiescence and promote post-injury regeneration of hematopoietic stem cells.
Nat. Med.
PUBLISHED: 05-27-2014
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Multiple bone marrow stromal cell types have been identified as hematopoietic stem cell (HSC)-regulating niche cells. However, whether HSC progeny can serve directly as HSC niche cells has not previously been shown. Here we report a dichotomous role of megakaryocytes (MKs) in both maintaining HSC quiescence during homeostasis and promoting HSC regeneration after chemotherapeutic stress. We show that MKs are physically associated with HSCs in the bone marrow of mice and that MK ablation led to activation of quiescent HSCs and increased HSC proliferation. RNA sequencing (RNA-seq) analysis revealed that transforming growth factor ?1 (encoded by Tgfb1) is expressed at higher levels in MKs as compared to other stromal niche cells. MK ablation led to reduced levels of biologically active TGF-?1 protein in the bone marrow and nuclear-localized phosphorylated SMAD2/3 (pSMAD2/3) in HSCs, suggesting that MKs maintain HSC quiescence through TGF-?-SMAD signaling. Indeed, TGF-?1 injection into mice in which MKs had been ablated restored HSC quiescence, and conditional deletion of Tgfb1 in MKs increased HSC activation and proliferation. These data demonstrate that TGF-?1 is a dominant signal emanating from MKs that maintains HSC quiescence. However, under conditions of chemotherapeutic challenge, MK ablation resulted in a severe defect in HSC expansion. In response to stress, fibroblast growth factor 1 (FGF1) signaling from MKs transiently dominates over TGF-? inhibitory signaling to stimulate HSC expansion. Overall, these observations demonstrate that MKs serve as HSC-derived niche cells to dynamically regulate HSC function.
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Polymicrobial airway bacterial communities in adult bronchiectasis patients.
BMC Microbiol.
PUBLISHED: 05-12-2014
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Chronic airway infection contributes to the underlying pathogenesis of non-cystic fibrosis bronchiectasis (NCFBr). In contrast to other chronic airway infections, associated with COPD and CF bronchiectasis, where polymicrobial communities have been implicated in lung damage due to the vicious circle of recurrent bacterial infections and inflammation, there is sparse information on the composition of bacterial communities in NCFBr. Seventy consecutive patients were recruited from an outpatient adult NCFBr clinic. Bacterial communities in sputum samples were analysed by culture and pyrosequencing approaches. Bacterial sequences were analysed using partial least square discrimination analyses to investigate trends in community composition and identify those taxa that contribute most to community variation.
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Genome-wide association study of sexual maturation in males and females highlights a role for body mass and menarche loci in male puberty.
Hum. Mol. Genet.
PUBLISHED: 04-25-2014
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Little is known about genes regulating male puberty. Further, while many identified pubertal timing variants associate with age at menarche, a late manifestation of puberty, and body mass, little is known about these variants' relationship to pubertal initiation or tempo. To address these questions, we performed genome-wide association meta-analysis in over 11 000 European samples with data on early pubertal traits, male genital and female breast development, measured by the Tanner scale. We report the first genome-wide significant locus for male sexual development upstream of myocardin-like 2 (MKL2) (P = 8.9 × 10(-9)), a menarche locus tagging a developmental pathway linking earlier puberty with reduced pubertal growth (P = 4.6 × 10(-5)) and short adult stature (p = 7.5 × 10(-6)) in both males and females. Furthermore, our results indicate that a proportion of menarche loci are important for pubertal initiation in both sexes. Consistent with epidemiological correlations between increased prepubertal body mass and earlier pubertal timing in girls, body mass index (BMI)-increasing alleles correlated with earlier breast development. In boys, some BMI-increasing alleles associated with earlier, and others with delayed, sexual development; these genetic results mimic the controversy in epidemiological studies, some of which show opposing correlations between prepubertal BMI and male puberty. Our results contribute to our understanding of the pubertal initiation program in both sexes and indicate that although mechanisms regulating pubertal onset in males and females may largely be shared, the relationship between body mass and pubertal timing in boys may be complex and requires further genetic studies.
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Long-term effects of analysis of the patient-therapist relationship in the context of patients' personality pathology and therapists' parental feelings.
J Consult Clin Psychol
PUBLISHED: 03-24-2014
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Analysis of the patient-therapist relationship (relationship work) is considered a core active ingredient in dynamic psychotherapy. However, there are contradictory findings as for whom and under what circumstances these interventions are beneficial. This study investigates long-term effects of relationship work in the context of patients' level of personality pathology and therapists' self-reported parental feelings.
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A rare variant in APOC3 is associated with plasma triglyceride and VLDL levels in Europeans.
Nat Commun
PUBLISHED: 03-07-2014
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The analysis of rich catalogues of genetic variation from population-based sequencing provides an opportunity to screen for functional effects. Here we report a rare variant in APOC3 (rs138326449-A, minor allele frequency ~0.25% (UK)) associated with plasma triglyceride (TG) levels (-1.43 s.d. (s.e.=0.27 per minor allele (P-value=8.0 × 10(-8))) discovered in 3,202 individuals with low read-depth, whole-genome sequence. We replicate this in 12,831 participants from five additional samples of Northern and Southern European origin (-1.0 s.d. (s.e.=0.173), P-value=7.32 × 10(-9)). This is consistent with an effect between 0.5 and 1.5 mmol l(-1) dependent on population. We show that a single predicted splice donor variant is responsible for association signals and is independent of known common variants. Analyses suggest an independent relationship between rs138326449 and high-density lipoprotein (HDL) levels. This represents one of the first examples of a rare, large effect variant identified from whole-genome sequencing at a population scale.
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Multisite Image Data Collection and Management Using the RSNA Image Sharing Network.
Transl Oncol
PUBLISHED: 02-01-2014
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The execution of a multisite trial frequently includes image collection. The Clinical Trials Processor (CTP) makes removal of protected health information highly reliable. It also provides reliable transfer of images to a central review site. Trials using central review of imaging should consider using CTP for handling image data when a multisite trial is being designed.
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Genome-wide trans-ancestry meta-analysis provides insight into the genetic architecture of type 2 diabetes susceptibility.
, Anubha Mahajan, Min Jin Go, Weihua Zhang, Jennifer E Below, Kyle J Gaulton, Teresa Ferreira, Momoko Horikoshi, Andrew D Johnson, Maggie C Y Ng, Inga Prokopenko, Danish Saleheen, Xu Wang, Eleftheria Zeggini, Gonçalo R Abecasis, Linda S Adair, Peter Almgren, Mustafa Atalay, Tin Aung, Damiano Baldassarre, Beverley Balkau, Yuqian Bao, Anthony H Barnett, Inês Barroso, Abdul Basit, Latonya F Been, John Beilby, Graeme I Bell, Rafn Benediktsson, Richard N Bergman, Bernhard O Boehm, Eric Boerwinkle, Lori L Bonnycastle, Noel Burtt, Qiuyin Cai, Harry Campbell, Jason Carey, Stéphane Cauchi, Mark Caulfield, Juliana C N Chan, Li-Ching Chang, Tien-Jyun Chang, Yi-Cheng Chang, Guillaume Charpentier, Chien-Hsiun Chen, Han Chen, Yuan-Tsong Chen, Kee-Seng Chia, Manickam Chidambaram, Peter S Chines, Nam H Cho, Young Min Cho, Lee-Ming Chuang, Francis S Collins, Marylin C Cornelis, David J Couper, Andrew T Crenshaw, Rob M Van Dam, John Danesh, Debashish Das, Ulf de Faire, George Dedoussis, Panos Deloukas, Antigone S Dimas, Christian Dina, Alex S Doney, Peter J Donnelly, Mozhgan Dorkhan, Cornelia van Duijn, Josée Dupuis, Sarah Edkins, Paul Elliott, Valur Emilsson, Raimund Erbel, Johan G Eriksson, Jorge Escobedo, Tonu Esko, Elodie Eury, Jose C Florez, Pierre Fontanillas, Nita G Forouhi, Tom Forsén, Caroline Fox, Ross M Fraser, Timothy M Frayling, Philippe Froguel, Philippe Frossard, Yutang Gao, Karl Gertow, Christian Gieger, Bruna Gigante, Harald Grallert, George B Grant, Leif C Grrop, Chrisropher J Groves, Elin Grundberg, Candace Guiducci, Anders Hamsten, Bok-Ghee Han, Kazuo Hara, Neelam Hassanali, Andrew T Hattersley, Caroline Hayward, Asa K Hedman, Christian Herder, Albert Hofman, Oddgeir L Holmen, Kees Hovingh, Astradur B Hreidarsson, Cheng Hu, Frank B Hu, Jennie Hui, Steve E Humphries, Sarah E Hunt, David J Hunter, Kristian Hveem, Zafar I Hydrie, Hiroshi Ikegami, Thomas Illig, Erik Ingelsson, Muhammed Islam, Bo Isomaa, Anne U Jackson, Tazeen Jafar, Alan James, Weiping Jia, Karl-Heinz Jöckel, Anna Jonsson, Jeremy B M Jowett, Takashi Kadowaki, Hyun Min Kang, Stavroula Kanoni, Wen Hong L Kao, Sekar Kathiresan, Norihiro Kato, Prasad Katulanda, Kirkka M Keinanen-Kiukaanniemi, Ann M Kelly, Hassan Khan, Kay-Tee Khaw, Chiea-Chuen Khor, Hyung-Lae Kim, Sangsoo Kim, Young Jin Kim, Leena Kinnunen, Norman Klopp, Augustine Kong, Eeva Korpi-Hyövälti, Sudhir Kowlessur, Peter Kraft, Jasmina Kravic, Malene M Kristensen, S Krithika, Ashish Kumar, Jesus Kumate, Johanna Kuusisto, Soo Heon Kwak, Markku Laakso, Vasiliki Lagou, Timo A Lakka, Claudia Langenberg, Cordelia Langford, Robert Lawrence, Karin Leander, Jen-Mai Lee, Nanette R Lee, Man Li, Xinzhong Li, Yun Li, Junbin Liang, Samuel Liju, Wei-Yen Lim, Lars Lind, Cecilia M Lindgren, Eero Lindholm, Ching-Ti Liu, Jian Jun Liu, Stéphane Lobbens, Jirong Long, Ruth J F Loos, Wei Lu, Jian'an Luan, Valeriya Lyssenko, Ronald C W Ma, Shiro Maeda, Reedik Mägi, Satu Mannisto, David R Matthews, James B Meigs, Olle Melander, Andres Metspalu, Julia Meyer, Ghazala Mirza, Evelin Mihailov, Susanne Moebus, Viswanathan Mohan, Karen L Mohlke, Andrew D Morris, Thomas W Mühleisen, Martina Müller-Nurasyid, Bill Musk, Jiro Nakamura, Eitaro Nakashima, Pau Navarro, Peng-Keat Ng, Alexandra C Nica, Peter M Nilsson, Inger Njølstad, Markus M Nöthen, Keizo Ohnaka, Twee Hee Ong, Katharine R Owen, Colin N A Palmer, James S Pankow, Kyong Soo Park, Melissa Parkin, Sonali Pechlivanis, Nancy L Pedersen, Leena Peltonen, John R B Perry, Annette Peters, Janini M Pinidiyapathirage, Carl G Platou, Simon Potter, Jackie F Price, Lu Qi, Venkatesan Radha, Loukianos Rallidis, Asif Rasheed, Wolfgang Rathman, Rainer Rauramaa, Soumya Raychaudhuri, N William Rayner, Simon D Rees, Emil Rehnberg, Samuli Ripatti, Neil Robertson, Michael Roden, Elizabeth J Rossin, Igor Rudan, Denis Rybin, Timo E Saaristo, Veikko Salomaa, Juha Saltevo, Maria Samuel, Dharambir K Sanghera, Jouko Saramies, James Scott, Laura J Scott, Robert A Scott, Ayellet V Segrè, Joban Sehmi, Bengt Sennblad, Nabi Shah, Sonia Shah, A Samad Shera, Xiao Ou Shu, Alan R Shuldiner, Gunnar Sigurđsson, Eric Sijbrands, Angela Silveira, Xueling Sim, Suthesh Sivapalaratnam, Kerrin S Small, Wing Yee So, Alena Stančáková, Kari Stefansson, Gerald Steinbach, Valgerdur Steinthorsdottir, Kathleen Stirrups, Rona J Strawbridge, Heather M Stringham, Qi Sun, Chen Suo, Ann-Christine Syvänen, Ryoichi Takayanagi, Fumihiko Takeuchi, Wan Ting Tay, Tanya M Teslovich, Barbara Thorand, Gudmar Thorleifsson, Unnur Thorsteinsdottir, Emmi Tikkanen, Joseph Trakalo, Elena Tremoli, Mieke D Trip, Fuu Jen Tsai, Tiinamaija Tuomi, Jaakko Tuomilehto, André G Uitterlinden, Adán Valladares-Salgado, Sailaja Vedantam, Fabrizio Veglia, Benjamin F Voight, Congrong Wang, Nicholas J Wareham, Roman Wennauer, Ananda R Wickremasinghe, Tom Wilsgaard, James F Wilson, Steven Wiltshire, Wendy Winckler, Tien Yin Wong, Andrew R Wood, Jer-Yuarn Wu, Ying Wu, Ken Yamamoto, Toshimasa Yamauchi, Mingyu Yang, Loïc Yengo, Mitsuhiro Yokota, Robin Young, Delilah Zabaneh, Fan Zhang, Rong Zhang, Wei Zheng, Paul Z Zimmet, David Altshuler, Donald W Bowden, Yoon Shin Cho, Nancy J Cox, Miguel Cruz, Craig L Hanis, Jaspal Kooner, Jong-Young Lee, Mark Seielstad, Yik Ying Teo, Michael Boehnke, Esteban J Parra, Jonh C Chambers, E Shyong Tai, Mark I McCarthy, Andrew P Morris.
Nat. Genet.
PUBLISHED: 01-17-2014
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To further understanding of the genetic basis of type 2 diabetes (T2D) susceptibility, we aggregated published meta-analyses of genome-wide association studies (GWAS), including 26,488 cases and 83,964 controls of European, east Asian, south Asian and Mexican and Mexican American ancestry. We observed a significant excess in the directional consistency of T2D risk alleles across ancestry groups, even at SNPs demonstrating only weak evidence of association. By following up the strongest signals of association from the trans-ethnic meta-analysis in an additional 21,491 cases and 55,647 controls of European ancestry, we identified seven new T2D susceptibility loci. Furthermore, we observed considerable improvements in the fine-mapping resolution of common variant association signals at several T2D susceptibility loci. These observations highlight the benefits of trans-ethnic GWAS for the discovery and characterization of complex trait loci and emphasize an exciting opportunity to extend insight into the genetic architecture and pathogenesis of human diseases across populations of diverse ancestry.
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The effect of ex vivo lung perfusion on microbial load in human donor lungs.
J. Heart Lung Transplant.
PUBLISHED: 01-09-2014
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Ex vivo lung perfusion (EVLP) has emerged as a technique to potentially recondition unusable donor lungs for transplantation. Beneficial effects of EVLP on physiologic function have been reported, but little is known about the effect of normothermic perfusion on the infectious burden of the donor lung. In this study, we investigated the effect of EVLP on the microbial load of human donor lungs.
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Synthesis of 2-arylbenzothiazole derivatives and their application in bacterial detection.
Bioorg. Med. Chem.
PUBLISHED: 01-06-2014
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A series of 2-arylbenzothiazole derivatives have been prepared as fluorogenic enzyme substrates in order to detect aminopeptidase, esterase, phosphatase and ?-galactosidase activity in clinically important Gram-negative and Gram-positive bacteria. Substrates were incorporated into an agar-based culture medium and this allowed growth of intensely fluorescent bacterial colonies based on hydrolysis by specific enzymes. Substrate 20 targeted L-alanine aminopeptidase activity and was hydrolysed exclusively by a range of Gram-negative bacteria and inhibited the growth of a range of Gram-positive bacteria. Substrate 19a targeted ?-alanyl aminopeptidase activity and generated fluorescent colonies of selected Gram-negative species including Pseudomonas aeruginosa. Substrate 21b targeted C8-esterase activity and resulted in strongly fluorescent colonies of selected species known to harbour such enzyme activity (e.g., Salmonella and Pseudomonas). Most Gram-negative species produced colonies with an intense blue fluorescence due to hydrolysis of phosphatase substrates 24a-c and substrate 24c was also hydrolysed by strains of Staphylococcus aureus. Compounds 26b and 26c targeted ?-galactosidase activity and generated strongly fluorescent colonies with coliform bacteria that produced this enzyme (e.g., Escherichia coli).
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DNA mismatch repair gene MSH6 implicated in determining age at natural menopause.
Hum. Mol. Genet.
PUBLISHED: 12-19-2013
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Length of female reproductive lifespan is associated with multiple adverse outcomes, including breast cancer, cardiovascular disease and infertility. The biological processes that govern the timing of the beginning and end of reproductive life are not well understood. Genetic variants are known to contribute to about 50% of the variation in both age at menarche and menopause, but to date the known genes explain <15% of the genetic component. We have used genome-wide association in a bivariate meta-analysis of both traits, to identify genes involved in determining reproductive lifespan. We observed significant genetic correlation between the two traits using Genome-wide Complex Trait Analysis (GCTA). However, we found no robust statistical evidence for individual variants with an effect on both traits. A novel association with age at menopause was detected for a variant rs1800932 in the mismatch repair gene MSH6 (P=1.9x10(-9)), which was also associated with altered expression levels of MSH6 mRNA in multiple tissues. This study contributes to the growing evidence that DNA repair processes play a key role in ovarian ageing and could be an important therapeutic target for infertility.
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Nocardia kroppenstedtii sp. nov., a novel actinomycete isolated from a lung transplant patient with a pulmonary infection.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 11-06-2013
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An actinomycete, strain N1286T, isolated from a lung transplant patient with a pulmonary infection, was provisionally assigned to the genus Nocardia. The strain had chemotaxonomic and morphological properties typical of members of the genus Nocardia and formed a distinct phyletic line in the Nocardia 16S rRNA gene tree. It was most closely related to Nocardia farcinica DSM 43665T (99.8% gene similarity) but was distinguished from the latter by a low level of DNA:DNA relatedness. These strains were also distinguished by a broad range of phenotypic properties. On the basis of these data, it is proposed that isolate N1286T (=DSM 45810T = NCTC 13617T) should be classified as the type strain of a new Nocardia species for which the name Nocardia kroppenstedtii is proposed.
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Biomarkers for type 2 diabetes and impaired fasting glucose using a nontargeted metabolomics approach.
Diabetes
PUBLISHED: 07-24-2013
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Using a nontargeted metabolomics approach of 447 fasting plasma metabolites, we searched for novel molecular markers that arise before and after hyperglycemia in a large population-based cohort of 2,204 females (115 type 2 diabetic [T2D] case subjects, 192 individuals with impaired fasting glucose [IFG], and 1,897 control subjects) from TwinsUK. Forty-two metabolites from three major fuel sources (carbohydrates, lipids, and proteins) were found to significantly correlate with T2D after adjusting for multiple testing; of these, 22 were previously reported as associated with T2D or insulin resistance. Fourteen metabolites were found to be associated with IFG. Among the metabolites identified, the branched-chain keto-acid metabolite 3-methyl-2-oxovalerate was the strongest predictive biomarker for IFG after glucose (odds ratio [OR] 1.65 [95% CI 1.39-1.95], P = 8.46 × 10(-9)) and was moderately heritable (h(2) = 0.20). The association was replicated in an independent population (n = 720, OR 1.68 [ 1.34-2.11], P = 6.52 × 10(-6)) and validated in 189 twins with urine metabolomics taken at the same time as plasma (OR 1.87 [1.27-2.75], P = 1 × 10(-3)). Results confirm an important role for catabolism of branched-chain amino acids in T2D and IFG. In conclusion, this T2D-IFG biomarker study has surveyed the broadest panel of nontargeted metabolites to date, revealing both novel and known associated metabolites and providing potential novel targets for clinical prediction and a deeper understanding of causal mechanisms.
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Dispositional coping, coping effectiveness, and cognitive social maturity among adolescent athletes.
J Sport Exerc Psychol
PUBLISHED: 06-27-2013
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It is accepted among scholars that coping changes as people mature during adolescence, but little is known about the relationship between maturity and coping. The purpose of this paper was to assess a model, which included dispositional coping, coping effectiveness, and cognitive social maturity. We predicted that cognitive social maturity would have a direct effect on coping effectiveness, and also an indirect impact via dispositional coping. Two hundred forty-five adolescent athletes completed measures of dispositional coping, coping effectiveness, and cognitive social maturity, which has three dimensions: conscientiousness, peer influence on behavior, and rule following. Using structural equation modeling, we found support for our model, suggesting that coping is related to cognitive social maturity. This information can be used to influence the content of coping interventions for adolescents of different maturational levels.
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Pseudocitrobacter gen. nov., a novel genus of the Enterobacteriaceae with two new species Pseudocitrobacter faecalis sp. nov., and Pseudocitrobacter anthropi sp. nov, isolated from fecal samples from hospitalized patients in Pakistan.
Syst. Appl. Microbiol.
PUBLISHED: 05-25-2013
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Four isolates of Gram-negative facultatively anaerobic bacteria, three of them producing NDM-1 carbapenemase, were isolated from hospitalized patients and outpatients attending two military hospitals in Rawalpindi, Pakistan, and studied for their taxonomic position. Initially the strains were phenotypically identified as Citrobacter species. Comparative analysis of 16S rRNA gene sequences then showed that the four strains shared >97%, but in no case >98.3%, 16S rRNA gene sequence similarities to members of the genera Citrobacter, Kluyvera, Pantoea, Enterobacter and Raoultella, but always formed a separate cluster in respective phylogenetic trees. Based on multilocus sequence analysis (MLSA) including partial recN, rpoA, thdF and rpoB gene sequence and respective amino acid sequence analysis it turned out that the strains also here always formed separate clusters. Based on further comparative analyses including DNA-DNA hybridizations, genomic fingerprint analysis using rep- and RAPD-PCRs and physiological tests, it is proposed to classify these four strains into the novel genus Pseudocitrobacter gen. nov. with a new species Pseudocitrobacter faecalis sp. nov. with strain 25 CIT(T) (=CCM 8479(T)=LMG 27751(T)) and Pseudocitrobacter anthropi sp. nov. with strain C138(T) (=CCM 8478(T)=LMG 27750(T)), as the type strains, respectively.
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Maternal imprinting at the H19-Igf2 locus maintains adult haematopoietic stem cell quiescence.
Nature
PUBLISHED: 05-15-2013
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The epigenetic regulation of imprinted genes by monoallelic DNA methylation of either maternal or paternal alleles is critical for embryonic growth and development. Imprinted genes were recently shown to be expressed in mammalian adult stem cells to support self-renewal of neural and lung stem cells; however, a role for imprinting per se in adult stem cells remains elusive. Here we show upregulation of growth-restricting imprinted genes, including in the H19-Igf2 locus, in long-term haematopoietic stem cells and their downregulation upon haematopoietic stem cell activation and proliferation. A differentially methylated region upstream of H19 (H19-DMR), serving as the imprinting control region, determines the reciprocal expression of H19 from the maternal allele and Igf2 from the paternal allele. In addition, H19 serves as a source of miR-675, which restricts Igf1r expression. We demonstrate that conditional deletion of the maternal but not the paternal H19-DMR reduces adult haematopoietic stem cell quiescence, a state required for long-term maintenance of haematopoietic stem cells, and compromises haematopoietic stem cell function. Maternal-specific H19-DMR deletion results in activation of the Igf2-Igfr1 pathway, as shown by the translocation of phosphorylated FoxO3 (an inactive form) from nucleus to cytoplasm and the release of FoxO3-mediated cell cycle arrest, thus leading to increased activation, proliferation and eventual exhaustion of haematopoietic stem cells. Mechanistically, maternal-specific H19-DMR deletion leads to Igf2 upregulation and increased translation of Igf1r, which is normally suppressed by H19-derived miR-675. Similarly, genetic inactivation of Igf1r partly rescues the H19-DMR deletion phenotype. Our work establishes a new role for this unique form of epigenetic control at the H19-Igf2 locus in maintaining adult stem cells.
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Identification of Volatile Organic Compounds Produced by Bacteria Using HS-SPME-GC-MS.
J Chromatogr Sci
PUBLISHED: 05-09-2013
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The analysis of volatile organic compounds (VOCs) as a tool for bacterial identification is reported. Headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS) was applied to the analysis of bacterial VOCs with the aim of determining the impact of experimental parameters on the generated VOC profiles. The effect of culture medium, SPME fiber type and GC column were fully evaluated with the Gram-negative bacteria Escherichia coli and Klebsiella pneumoniae and the Gram-positive species Staphylococcus aureus. Multivariate analysis, including cluster analysis and principal component analysis, was applied to VOC data to determine whether the parameters under investigation significantly affected bacterial VOC profiles. Culture medium, and to a lesser extent, SPME fiber type, were found to significantly alter detected bacterial VOC profiles. The detected VOCs varied little with the polarity of the GC column. The results indicate that the generated bacterial VOC profiles need careful evaluation if they are to be used for clinical diagnostics. The whole process is limited by the need to grow the bacteria in broth (18 h) before extraction and analysis (63 min).
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Screening metal-organic frameworks for selective noble gas adsorption in air: effect of pore size and framework topology.
Phys Chem Chem Phys
PUBLISHED: 05-03-2013
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The adsorption of noble gases and nitrogen by sixteen metal-organic frameworks (MOFs) was investigated using grand canonical Monte Carlo simulation. The MOFs were chosen to represent a variety of net topologies, pore dimensions, and metal centers. Three commercially available MOFs (HKUST-1, AlMIL-53, and ZIF-8) and PCN-14 were also included for comparison. Experimental adsorption isotherms, obtained from volumetric and gravimetric methods, were used to compare krypton, argon, and nitrogen uptake with the simulation results. Simulated trends in gas adsorption and predicted selectivities among the commercially available MOFs are in good agreement with experiment. In the low pressure regime, the expected trend of increasing adsorption with increasing noble gas polarizabilty is seen. For each noble gas, low pressure adsorption correlates with several MOF properties, including free volume, topology, and metal center. Additionally, a strong correlation exists between the Henrys constant and the isosteric heat of adsorption for all gases and MOFs considered. Finally, we note that the simulated and experimental gas selectivities demonstrated by this small set of MOFs show improved performance compared to similar values reported for zeolites.
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Aetiology of paediatric pneumonia after the introduction of pneumococcal conjugate vaccine.
Eur. Respir. J.
PUBLISHED: 04-18-2013
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We describe the aetiology of community-acquired pneumonia in children before and after the introduction of the pneumococcal conjugate vaccination (PCV) programme in 2006. Prospective studies were conducted in 2001-2002 (pre-vaccine) and 2009-2011 (post-vaccine) of children aged 0-16 years with radiologically confirmed pneumonia seen in hospital. Investigations included culture, serology, immunofluorescence antibody and urine antigen testing, with an increased use of PCR assays and expanded panels of pathogens in the post-vaccine study. 241 and 160 children were enrolled in the pre- and post-vaccine studies, respectively (73% aged <5 years). Identification of a causative pathogen was higher post-vaccination (61%) than pre-vaccination (48.5%) (p=0.019). Rates of bacterial infections were not different between post- and pre-vaccine studies (17.5% versus 24%, p=0.258). Viral (31%) and mixed (12.5%) infections were found more often post-vaccination (19.5%, p=0.021) than pre-vaccination (5%, p=0.015). Rates of identified pneumococcal infections were comparable between pre- and post-vaccine studies (14.7% versus 17.4%, p=0.557). Diagnosis of pneumococcal infection post-vaccination improved when PCR was used compared to culture (21.6% versus 6%, p=0.0004). Serotypes included in PCV13 but not PCV7 were identified in 75% (18 out of 24) post-vaccination. Infection with nonvaccine pneumococcal serotypes continues to be a significant cause of pneumonia in children in the UK.
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Shared genetic factors for age at natural menopause in Iranian and European women.
Hum. Reprod.
PUBLISHED: 04-16-2013
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Do differences in heritable genetic factors explain some of the difference in age at natural menopause (ANM) among populations?
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Isolation and characterization of intestinal stem cells based on surface marker combinations and colony-formation assay.
Gastroenterology
PUBLISHED: 04-10-2013
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Identification of intestinal stem cells (ISCs) has relied heavily on the use of transgenic reporters in mice, but this approach is limited by mosaic expression patterns and difficult to directly apply to human tissues. We sought to identify reliable surface markers of ISCs and establish a robust functional assay to characterize ISCs from mouse and human tissues.
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Use of faropenem as an indicator of carbapenemase activity in the Enterobacteriaceae.
J. Clin. Microbiol.
PUBLISHED: 04-10-2013
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The aim of this study was to determine the ability of a disc susceptibility test using faropenem (10 ?g) to predict carbapenemase activity in Enterobacteriaceae. A collection of 166 isolates of carbapenemase-producing Enterobacteriaceae (CPE) and 82 isolates of Enterobacteriaceae that produced other ?-lactamases was compiled from diverse sources. Disc susceptibility testing was performed using the CLSI/EUCAST methodology with discs of faropenem (10 ?g), temocillin (30 ?g), and four carbapenems (each 10 ?g). A further prospective evaluation of the faropenem disc susceptibility test was performed using 205 consecutive isolates referred to a United Kingdom reference laboratory in parallel with molecular methods for carbapenemase detection. Of 166 isolates of CPE, 99% showed growth up to the edge of a 10-?g faropenem disc compared with only 6% of other ?-lactamase producers (sensitivity, 99%; specificity, 94%). A "double zone" around 10-?g faropenem discs was frequently associated with OXA-48 producers. Of the carbapenems, the most useful agent was imipenem, where a zone diameter of ? 23 mm as a predictor of carbapenemase activity had a sensitivity of 99% and a specificity of 85%. The presence of no zone of inhibition around a 30-?g temocillin disc was a consistent feature of strains producing OXA-48 carbapenemase. For 205 isolates of Enterobacteriaceae referred to a United Kingdom reference laboratory, growth up to a 10-?g faropenem disc correctly identified 84 of 86 carbapenemase producers (98% sensitivity), with a specificity of 87%. Disc susceptibility testing using faropenem (10 ?g) is a simple, convenient, and highly predictive screening test for carbapenemase-producing Enterobacteriaceae.
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Association of adiposity genetic variants with menarche timing in 92,105 women of European descent.
Am. J. Epidemiol.
PUBLISHED: 04-04-2013
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Obesity is of global health concern. There are well-described inverse relationships between female pubertal timing and obesity. Recent genome-wide association studies of age at menarche identified several obesity-related variants. Using data from the ReproGen Consortium, we employed meta-analytical techniques to estimate the associations of 95 a priori and recently identified obesity-related (body mass index (weight (kg)/height (m)(2)), waist circumference, and waist:hip ratio) single-nucleotide polymorphisms (SNPs) with age at menarche in 92,116 women of European descent from 38 studies (1970-2010), in order to estimate associations between genetic variants associated with central or overall adiposity and pubertal timing in girls. Investigators in each study performed a separate analysis of associations between the selected SNPs and age at menarche (ages 9-17 years) using linear regression models and adjusting for birth year, site (as appropriate), and population stratification. Heterogeneity of effect-measure estimates was investigated using meta-regression. Six novel associations of body mass index loci with age at menarche were identified, and 11 adiposity loci previously reported to be associated with age at menarche were confirmed, but none of the central adiposity variants individually showed significant associations. These findings suggest complex genetic relationships between menarche and overall obesity, and to a lesser extent central obesity, in normal processes of growth and development.
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Genome-wide association and longitudinal analyses reveal genetic loci linking pubertal height growth, pubertal timing and childhood adiposity.
Hum. Mol. Genet.
PUBLISHED: 02-27-2013
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The pubertal height growth spurt is a distinctive feature of childhood growth reflecting both the central onset of puberty and local growth factors. Although little is known about the underlying genetics, growth variability during puberty correlates with adult risks for hormone-dependent cancer and adverse cardiometabolic health. The only gene so far associated with pubertal height growth, LIN28B, pleiotropically influences childhood growth, puberty and cancer progression, pointing to shared underlying mechanisms. To discover genetic loci influencing pubertal height and growth and to place them in context of overall growth and maturation, we performed genome-wide association meta-analyses in 18 737 European samples utilizing longitudinally collected height measurements. We found significant associations (P < 1.67 × 10(-8)) at 10 loci, including LIN28B. Five loci associated with pubertal timing, all impacting multiple aspects of growth. In particular, a novel variant correlated with expression of MAPK3, and associated both with increased prepubertal growth and earlier menarche. Another variant near ADCY3-POMC associated with increased body mass index, reduced pubertal growth and earlier puberty. Whereas epidemiological correlations suggest that early puberty marks a pathway from rapid prepubertal growth to reduced final height and adult obesity, our study shows that individual loci associating with pubertal growth have variable longitudinal growth patterns that may differ from epidemiological observations. Overall, this study uncovers part of the complex genetic architecture linking pubertal height growth, the timing of puberty and childhood obesity and provides new information to pinpoint processes linking these traits.
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Bacterial and fungal viability in the preterm gut: NEC and sepsis.
Arch. Dis. Child. Fetal Neonatal Ed.
PUBLISHED: 02-20-2013
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Evidence suggests that microbial communities in the preterm gut may influence the development of necrotising enterocolitis (NEC) and sepsis. Existing data often neglect fungi and whether bacteria were metabolically active or not. We sought to characterise the bacterial and fungal stool flora of preterm neonates and organism viability and evaluate any associations with NEC and sepsis.
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Pneumococcal diagnosis and serotypes in childhood community-acquired pneumonia.
Diagn. Microbiol. Infect. Dis.
PUBLISHED: 02-12-2013
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The 7-valent pneumococcal conjugate vaccine (PCV7) was introduced routinely in the UK from September 2006 and replaced by PCV13 in 2010. In a prospective study from 2009 to 2011 of 160 children aged ?16 years with radiologically confirmed pneumonia, likely pneumococcal infections were identified in 26%. Detection of pneumococci was improved with polymerase chain reaction compared to culture (21.6% versus 6% of children tested, P = 0.0004). Where serotyping was possible, all (n = 23) were non-PCV7 but PCV13 serotypes; 1 (43.5%), 3 (21.7%), 7A/F, and 19A (17.4% each).
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A genome-wide association study of early menopause and the combined impact of identified variants.
Hum. Mol. Genet.
PUBLISHED: 01-09-2013
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Early menopause (EM) affects up to 10% of the female population, reducing reproductive lifespan considerably. Currently, it constitutes the leading cause of infertility in the western world, affecting mainly those women who postpone their first pregnancy beyond the age of 30 years. The genetic aetiology of EM is largely unknown in the majority of cases. We have undertaken a meta-analysis of genome-wide association studies (GWASs) in 3493 EM cases and 13 598 controls from 10 independent studies. No novel genetic variants were discovered, but the 17 variants previously associated with normal age at natural menopause as a quantitative trait (QT) were also associated with EM and primary ovarian insufficiency (POI). Thus, EM has a genetic aetiology which overlaps variation in normal age at menopause and is at least partly explained by the additive effects of the same polygenic variants. The combined effect of the common variants captured by the single nucleotide polymorphism arrays was estimated to account for ?30% of the variance in EM. The association between the combined 17 variants and the risk of EM was greater than the best validated non-genetic risk factor, smoking.
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Development of the preterm gut microbiome in twins at risk of necrotising enterocolitis and sepsis.
PLoS ONE
PUBLISHED: 01-01-2013
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The preterm gut microbiome is a complex dynamic community influenced by genetic and environmental factors and is implicated in the pathogenesis of necrotising enterocolitis (NEC) and sepsis. We aimed to explore the longitudinal development of the gut microbiome in preterm twins to determine how shared environmental and genetic factors may influence temporal changes and compared this to the expressed breast milk (EBM) microbiome. Stool samples (n = 173) from 27 infants (12 twin pairs and 1 triplet set) and EBM (n = 18) from 4 mothers were collected longitudinally. All samples underwent PCR-DGGE (denaturing gradient gel electrophoresis) analysis and a selected subset underwent 454 pyrosequencing. Stool and EBM shared a core microbiome dominated by Enterobacteriaceae, Enterococcaceae, and Staphylococcaceae. The gut microbiome showed greater similarity between siblings compared to unrelated individuals. Pyrosequencing revealed a reduction in diversity and increasing dominance of Escherichia sp. preceding NEC that was not observed in the healthy twin. Antibiotic treatment had a substantial effect on the gut microbiome, reducing Escherichia sp. and increasing other Enterobacteriaceae. This study demonstrates related preterm twins share similar gut microbiome development, even within the complex environment of neonatal intensive care. This is likely a result of shared genetic and immunomodulatory factors as well as exposure to the same maternal microbiome during birth, skin contact and exposure to EBM. Environmental factors including antibiotic exposure and feeding are additional significant determinants of community structure, regardless of host genetics.
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Imputation of variants from the 1000 Genomes Project modestly improves known associations and can identify low-frequency variant-phenotype associations undetected by HapMap based imputation.
PLoS ONE
PUBLISHED: 01-01-2013
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Genome-wide association (GWA) studies have been limited by the reliance on common variants present on microarrays or imputable from the HapMap Project data. More recently, the completion of the 1000 Genomes Project has provided variant and haplotype information for several million variants derived from sequencing over 1,000 individuals. To help understand the extent to which more variants (including low frequency (1% ? MAF <5%) and rare variants (<1%)) can enhance previously identified associations and identify novel loci, we selected 93 quantitative circulating factors where data was available from the InCHIANTI population study. These phenotypes included cytokines, binding proteins, hormones, vitamins and ions. We selected these phenotypes because many have known strong genetic associations and are potentially important to help understand disease processes. We performed a genome-wide scan for these 93 phenotypes in InCHIANTI. We identified 21 signals and 33 signals that reached P<5×10(-8) based on HapMap and 1000 Genomes imputation, respectively, and 9 and 11 that reached a stricter, likely conservative, threshold of P<5×10(-11) respectively. Imputation of 1000 Genomes genotype data modestly improved the strength of known associations. Of 20 associations detected at P<5×10(-8) in both analyses (17 of which represent well replicated signals in the NHGRI catalogue), six were captured by the same index SNP, five were nominally more strongly associated in 1000 Genomes imputed data and one was nominally more strongly associated in HapMap imputed data. We also detected an association between a low frequency variant and phenotype that was previously missed by HapMap based imputation approaches. An association between rs112635299 and alpha-1 globulin near the SERPINA gene represented the known association between rs28929474 (MAF?=?0.007) and alpha1-antitrypsin that predisposes to emphysema (P?=?2.5×10(-12)). Our data provide important proof of principle that 1000 Genomes imputation will detect novel, low frequency-large effect associations.
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Low-frequency variants in HMGA1 are not associated with type 2 diabetes risk.
Diabetes
PUBLISHED: 12-30-2011
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It has recently been suggested that the low-frequency c.136-14_136-13insC variant in high-mobility group A1 (HMGA1) may strongly contribute to insulin resistance and type 2 diabetes risk. In our study, we attempted to confirm that HMGA1 is a novel type 2 diabetes locus in French Caucasians. The gene was sequenced in 368 type 2 diabetic case subjects with a family history of type 2 diabetes and 372 normoglycemic control subjects without a family history of type 2 diabetes. None of the 41 genetic variations identified were associated with type 2 diabetes. The lack of association between the c.136-14_136-13insC variant and type 2 diabetes was confirmed in an independent French group of 4,538 case subjects and 4,015 control subjects and in a large meta-analysis of 16,605 case subjects and 46,179 control subjects. Finally, this variant had no effects on metabolic traits and was not involved in variations of HMGA1 and insulin receptor (INSR) expressions. The c.136-14_136-13insC variant was not associated with type 2 diabetes in individuals of European descent. Our study emphasizes the need to analyze a large number of subjects to reliably assess the association of low-frequency variants with the disease.
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Propagating concentration polarization and ionic current rectification in a nanochannel-nanofunnel device.
Anal. Chem.
PUBLISHED: 12-13-2011
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We study ionic current rectification observed in a nanofluidic device with a nanofunnel positioned between two straight nanochannels. Ion transport is simulated by resolving the coupled three-dimensional Nernst-Planck, Poisson, and Navier-Stokes equations. In the modeled system, the electric double layer extends into the channel, and consequently, the funnel tip exhibits charge-selective properties, which results in the formation of enriched and depleted concentration polarization (CP) zones within the nanofunnel in the high- and low-conductance states, respectively. This scenario is similar to the one observed for ion transport through a charged conical nanopore connecting two macroscopic reservoirs. However, the presence of the adjacent straight nanochannels allows the CP zones to propagate out of the funnel into the adjoining channels. The condition for propagation of the CP zones is determined by several parameters, including the electroosmotic flow velocity. We demonstrate that in the high-conductance regime the modeled system is characterized by increased ionic concentrations in the entire cathodic nanochannel, whereas in the low-conductance state the depleted CP zone does not propagate out of the funnel and remains localized. The required three-dimensional modeling scheme is implemented on a parallel computational platform, is general as well as numerically efficient, and will be useful in the study of more advanced nanofluidic device designs for tailoring ionic current rectification.
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Guidelines for the diagnosis and antibiotic treatment of endocarditis in adults: a report of the Working Party of the British Society for Antimicrobial Chemotherapy.
J. Antimicrob. Chemother.
PUBLISHED: 11-14-2011
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The BSAC guidelines on treatment of infectious endocarditis (IE) were last published in 2004. The guidelines presented here have been updated and extended to reflect developments in diagnostics, new trial data and the availability of new antibiotics. The aim of these guidelines, which cover both native valve and prosthetic valve endocarditis, is to standardize the initial investigation and treatment of IE. An extensive review of the literature using a number of different search criteria has been carried out and cited publications used to support any changes we have made to the existing guidelines. Publications referring to in vitro or animal models have only been cited if appropriate clinical data are not available. Randomized, controlled trials suitable for the development of evidenced-based guidelines in this area are still lacking and therefore a consensus approach has again been adopted for most recommendations; however, we have attempted to grade the evidence, where possible. The guidelines have also been extended by the inclusion of sections on clinical diagnosis, echocardiography and surgery.
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A preliminary investigation into the effect of the use of the Short Message Service (SMS) on patient attendance at an NHS Dental Access Centre in Scotland.
Prim Dent Care
PUBLISHED: 10-05-2011
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This study´s aim was to assess whether the use of Short Message Service (SMS) text reminders sent to patients prior to their dental appointments improved attendance rates for two dentists at a dental access centre in Kirkcaldy, Fife, Scotland.
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Towards improved organisational support for nurses working in research roles in the clinical setting: a mixed method investigation.
Collegian
PUBLISHED: 10-01-2011
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The clinical research workforce within nursing is growing including those employed to lead studies, coordinate research and many hybrid roles. Several studies have reported high job satisfaction among research nurses. However, there have also been reports of limited options for career development and professional integration, likely reflecting typical informal, departmentally based management models. Institution-wide studies of issues related to research nurses are lacking, thus hampering the design and implementation of effective organisational frameworks to support and develop these positions.
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SmaI restriction site-based multiplex PCR for typing of hospital- and community-acquired Staphylococcus aureus.
J. Clin. Microbiol.
PUBLISHED: 09-21-2011
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Methicillin-resistant Staphylococcus aureus (MRSA) is an important nosocomial pathogen, and morbidity and mortality rates associated with this pathogen have increased markedly in recent years. MRSA strains are generally resistant to several classes of antibiotics and are therefore difficult and costly to treat. A major issue is to identify the sources of MRSA infections and to monitor their epidemic spread. In this study, we report the development of a typing technique for S. aureus, based on single-nucleotide polymorphism (SNP) variations in and around SmaI-restriction sites (CCCGGG). An assessment of the SmaI restriction site-based multiplex PCR (SmaI-multiplex PCR) typing (SMT) with respect to pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) revealed a high level of concordance in the clustering of the test strains. The SmaI-multiplex PCR was found to be more discriminatory than MLST/staphylococcal cassette chromosome mec (SCCmec) typing but less discriminatory than PFGE. SMT can provide real-time information for the investigation of ongoing S. aureus hospital outbreaks. SMT meets the criteria of a practical typing method: it is simple, reproducible, and highly discriminatory and does not require expensive equipment or specialist expertise. Consequently, SmaI-multiplex PCR has the potential to be used in routine clinical microbiology laboratories.
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Cooperation between both Wnt/{beta}-catenin and PTEN/PI3K/Akt signaling promotes primitive hematopoietic stem cell self-renewal and expansion.
Genes Dev.
PUBLISHED: 09-02-2011
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Although self-renewal is the central property of stem cells, the underlying mechanism remains inadequately defined. Using a hematopoietic stem and progenitor cell (HSPC)-specific conditional induction line, we generated a compound genetic model bearing both Pten deletion and ?-catenin activation. These double mutant mice exhibit a novel phenotype, including expansion of phenotypic long-term hematopoietic stem cells (LT-HSCs) without extensive differentiation. Unexpectedly, constitutive activation of ?-catenin alone results in apoptosis of HSCs. However, together, the Wnt/?-catenin and PTEN/PI3k/Akt pathways interact to drive phenotypic LT-HSC expansion by inducing proliferation while simultaneously inhibiting apoptosis and blocking differentiation, demonstrating the necessity of complementary cooperation between the two pathways in promoting self-renewal. Mechanistically, ?-catenin activation reduces multiple differentiation-inducing transcription factors, blocking differentiation partially through up-regulation of Inhibitor of differentiation 2 (Id2). In double mutants, loss of Pten enhances the HSC anti-apoptotic factor Mcl-1. All of these contribute in a complementary way to HSC self-renewal and expansion. While permanent, genetic alteration of both pathways in double mutant mice leads to expansion of phenotypic HSCs, these HSCs cannot function due to blocked differentiation. We developed a pharmacological approach to expand normal, functional HSCs in culture using factors that reversibly activate both Wnt/?-catenin and PI3K/Akt signaling simultaneously. We show for the first time that activation of either single pathway is insufficient to expand primitive HSCs, but in combination, both pathways drive self-renewal and expansion of HSCs with long-term functional capacity.
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Prevalence of faecal carriage of Enterobacteriaceae with NDM-1 carbapenemase at military hospitals in Pakistan, and evaluation of two chromogenic media.
J. Antimicrob. Chemother.
PUBLISHED: 07-25-2011
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To determine the prevalence and antimicrobial susceptibility of carbapenemase-producing Enterobacteriaceae among hospitalized patients and outpatients attending two military hospitals in Rawalpindi, Pakistan, and to compare the performance of two chromogenic culture media for the isolation of these organisms.
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In vitro activity of S-(3,4-dichlorobenzyl)isothiourea hydrochloride and novel structurally related compounds against multidrug-resistant bacteria, including Pseudomonas aeruginosa and Burkholderia cepacia complex.
Int. J. Antimicrob. Agents
PUBLISHED: 05-31-2011
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The aim of this study was to establish the antimicrobial activities of S-(3,4-dichlorobenzyl)isothiourea hydrochloride (A22) and a series of structurally related compounds against multidrug-resistant (MDR) bacteria. The minimum inhibitory concentrations (MICs) of 21 compounds were determined against 18 strains of pathogenic bacteria in addition to Pseudomonas aeruginosa (n=19) and Burkholderia cepacia complex (BCC) (n=20) isolated from the sputa of cystic fibrosis patients. Selected compounds were tested against further isolates, including P. aeruginosa (n=100), BCC (n=12) and Stenotrophomonas maltophilia (n=19). The interaction of S-(4-chlorobenzyl)isothiourea hydrochloride (C2) in combination with conventional antimicrobials was examined against 10 P. aeruginosa strains. Selected compounds were also tested against Enterobacteriaceae producing NDM-1 carbapenemase (n=64) and meticillin-resistant Staphylococcus aureus (MRSA) (n=37). Of the 21 compounds, 14 showed antimicrobial activity that was generally more pronounced against Gram-negative bacteria. Against P. aeruginosa, the most active compound was C2 [MIC for 50% of the organisms (MIC(50))=32?g/mL]. This compound was also the most active against BCC, with all isolates inhibited by 64?g/mL. For all ten strains of P. aeruginosa subjected to combination testing with C2 and conventional antimicrobials, a bactericidal effect was achieved with at least one combination. C2 and A22 both showed strong activity [MIC for 90% of the organisms (MIC(90))=4?g/mL] against Enterobacteriaceae that produced NDM-1 carbapenemase. Finally, S-(4-chlorobenzyl)-N-(2,4-dichlorophenyl)isothiourea hydrochloride showed good activity (MIC(90)=8?g/mL) against MRSA. This work establishes the activity of isothiourea derivatives against a broad range of clinically important MDR bacteria.
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Transport and sensing in nanofluidic devices.
Annu Rev Anal Chem (Palo Alto Calif)
PUBLISHED: 04-05-2011
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Ion transport and sensing in nanofluidic devices are receiving a great deal of attention because of their unique transport properties and potential analytical applications. Some aspects of microscale transport transfer directly to the nanoscale, but nanofluidic systems can be significantly influenced by phenomena such as double-layer overlap, surface charge, ion-current rectification, diffusion, and entropic forces, which are either insignificant or absent in larger microchannels. Micro- and nanofabrication techniques create features with a wide range of well-defined geometries and dimensions in synthetic and solid-state substrates. Moreover, these techniques permit coupling of multiple nano- and microscale elements, which can execute various functions. We discuss basic nanofluidic architectures, material transport properties through single and multiple nanochannels, and characterization of single particles by resistive-pulse sensing.
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Genetic determinants of serum testosterone concentrations in men.
PLoS Genet.
PUBLISHED: 04-04-2011
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Testosterone concentrations in men are associated with cardiovascular morbidity, osteoporosis, and mortality and are affected by age, smoking, and obesity. Because of serum testosterones high heritability, we performed a meta-analysis of genome-wide association data in 8,938 men from seven cohorts and followed up the genome-wide significant findings in one in silico (n?=?871) and two de novo replication cohorts (n?=?4,620) to identify genetic loci significantly associated with serum testosterone concentration in men. All these loci were also associated with low serum testosterone concentration defined as <300 ng/dl. Two single-nucleotide polymorphisms at the sex hormone-binding globulin (SHBG) locus (17p13-p12) were identified as independently associated with serum testosterone concentration (rs12150660, p?=?1.2×10(-41) and rs6258, p?=?2.3×10(-22)). Subjects with ? 3 risk alleles of these variants had 6.5-fold higher risk of having low serum testosterone than subjects with no risk allele. The rs5934505 polymorphism near FAM9B on the X chromosome was also associated with testosterone concentrations (p?=?5.6×10(-16)). The rs6258 polymorphism in exon 4 of SHBG affected SHBGs affinity for binding testosterone and the measured free testosterone fraction (p<0.01). Genetic variants in the SHBG locus and on the X chromosome are associated with a substantial variation in testosterone concentrations and increased risk of low testosterone. rs6258 is the first reported SHBG polymorphism, which affects testosterone binding to SHBG and the free testosterone fraction and could therefore influence the calculation of free testosterone using law-of-mass-action equation.
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MicroRNA programs in normal and aberrant stem and progenitor cells.
Genome Res.
PUBLISHED: 03-30-2011
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Emerging evidence suggests that microRNAs (miRNAs), an abundant class of ?22-nucleotide small regulatory RNAs, play key roles in controlling the post-transcriptional genetic programs in stem and progenitor cells. Here we systematically examined miRNA expression profiles in various adult tissue-specific stem cells and their differentiated counterparts. These analyses revealed miRNA programs that are common or unique to blood, muscle, and neural stem cell populations and miRNA signatures that mark the transitions from self-renewing and quiescent stem cells to proliferative and differentiating progenitor cells. Moreover, we identified a stem/progenitor transition miRNA (SPT-miRNA) signature that predicts the effects of genetic perturbations, such as loss of PTEN and the Rb family, AML1-ETO9a expression, and MLL-AF10 transformation, on self-renewal and proliferation potentials of mutant stem/progenitor cells. We showed that some of the SPT-miRNAs control the self-renewal of embryonic stem cells and the reconstitution potential of hematopoietic stem cells (HSCs). Finally, we demonstrated that SPT-miRNAs coordinately regulate genes that are known to play roles in controlling HSC self-renewal, such as Hoxb6 and Hoxa4. Together, these analyses reveal the miRNA programs that may control key processes in normal and aberrant stem and progenitor cells, setting the foundations for dissecting post-transcriptional regulatory networks in stem cells.
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2-Arylbenzothiazole, benzoxazole and benzimidazole derivatives as fluorogenic substrates for the detection of nitroreductase and aminopeptidase activity in clinically important bacteria.
Bioorg. Med. Chem.
PUBLISHED: 03-11-2011
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A series of 2-(2-nitrophenyl)benzothiazole 7, 2-(2-nitrophenyl)benzoxazole 10 and 2-(2-nitrophenyl)benzimidazole 13 derivatives have been synthesised and assessed as indicators of nitroreductase activity across a range of clinically important Gram negative and Gram positive bacteria. The majority of Gram negative bacteria produced strongly fluorescent colonies with substrates 7 and 10 whereas fluorescence production in Gram positive bacteria was less widespread. The l-alanine 16 and 19 and ?-alanine 21 and 23 derivatives have been prepared from 2-(2-aminophenyl)benzothiazole 14 and 2-(2-aminophenyl)benzoxazole 17. These four compounds have been evaluated as indicators of aminopeptidase activity. The growth of Gram positive bacteria was generally inhibited by these substrates but fluorescent colonies were produced with the majority of Gram negative bacteria tested.
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Nanoparticles by decomposition of long chain iron carboxylates: from spheres to stars and cubes.
Langmuir
PUBLISHED: 02-04-2011
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In this paper, we report the influence of reaction conditions and the chain length on the nanoparticle (NP) size and morphology for thermal decomposition of long-chain iron carboxylates such as Fe(III) oleate, palmitate, and myristate. In the majority of cases, spherical NPs are obtained; however, nonspherical morphologies were observed in some "extreme" conditions. For example, iron oxide nanostars are formed in eicosane at the Fe oleate/oleic acid ratio of 0.49 g/mL: the highest oleic acid content when NPs still form. The cubic NPs with flat facets are obtained by decomposition of iron palmitate at the lowest palmitic acid fractions, but the most monodisperse cubes are formed at the Fe palmitate/palmitic acid ratio of 1.19 g/mL. Elliptical NPs are formed from Fe myristate with the most well-defined structure. Easy transformation of these NPs from wüstite to maghemite without aggregation and loss of solubility makes them excellent candidates for biomedical applications after proper functionalization described in our preceding papers.
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Eight common genetic variants associated with serum DHEAS levels suggest a key role in ageing mechanisms.
PLoS Genet.
PUBLISHED: 01-27-2011
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Dehydroepiandrosterone sulphate (DHEAS) is the most abundant circulating steroid secreted by adrenal glands--yet its function is unknown. Its serum concentration declines significantly with increasing age, which has led to speculation that a relative DHEAS deficiency may contribute to the development of common age-related diseases or diminished longevity. We conducted a meta-analysis of genome-wide association data with 14,846 individuals and identified eight independent common SNPs associated with serum DHEAS concentrations. Genes at or near the identified loci include ZKSCAN5 (rs11761528; p = 3.15 × 10(-36)), SULT2A1 (rs2637125; p =? 2.61 × 10(-19)), ARPC1A (rs740160; p =? 1.56 × 10(-16)), TRIM4 (rs17277546; p =? 4.50 × 10(-11)), BMF (rs7181230; p = 5.44 × 10(-11)), HHEX (rs2497306; p =? 4.64 × 10(-9)), BCL2L11 (rs6738028; p = 1.72 × 10(-8)), and CYP2C9 (rs2185570; p = 2.29 × 10(-8)). These genes are associated with type 2 diabetes, lymphoma, actin filament assembly, drug and xenobiotic metabolism, and zinc finger proteins. Several SNPs were associated with changes in gene expression levels, and the related genes are connected to biological pathways linking DHEAS with ageing. This study provides much needed insight into the function of DHEAS.
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Study of polymeric interactions of copolymers: 2-hydroxyethyl methacrylate (HEMA) and 2,3-dihydroxypropyl methacrylate (DHPMA) with copper hydroxylated nanoballs.
J Nanosci Nanotechnol
PUBLISHED: 12-08-2010
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2-hydroxyethyl methacrylate (HEMA) and 2,3-dihydroxypropyl methacrylate (DHPMA) were used to synthesize novel nanocomposites containing 0.5% by weight of copper hydroxylated nanoballs. Glass transition temperatures of the copolymers and their respective nanocomposites were determined by using differential scanning calorimetry (DSC). Thermogravimetric analysis (TGA) was employed to measure the degradation temperatures of the samples and to determine if the degradation is a single step process or multiple step process. The dielectric permittivity (epsilon) and loss factor (epsilon") were measured via Dielectric Analysis (DEA) in the frequency range 0.1 Hz to 100 kHz and between the temperature -150 to 190 degrees C. gamma, beta, and alphabeta conductivity relaxations were revealed using the electric modulus formalism. The activation energies for the relaxations were calculated. Argand plots of M" versus M were used to study the viscoelastic effects of both copolymer and the composites. Herein we show that it is possible to tune solubility and relaxation properties which are important to the design of new biomaterials.
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Regulatory compliance requirements for an open source electronic image trial management system.
Conf Proc IEEE Eng Med Biol Soc
PUBLISHED: 11-25-2010
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There is a global need for software to manage imaging based clinical trials to speed basic research and drug development. Such a system must comply with regulatory requirements. The U.S. Food and Drug Administration (FDA) has regulations regarding software development process controls and data provenance tracking. A key unanswered problem is the identification of which data changes are significant given a workflow model for image trial management. We report on the results of our study of provenance tracking requirements and define an architecture and software development process that meets U.S. regulatory requirements using open source software components.
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Assessing the purity of metal-organic frameworks using photoluminescence: MOF-5, ZnO quantum dots, and framework decomposition.
J. Am. Chem. Soc.
PUBLISHED: 10-22-2010
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Photoluminescence (PL) spectroscopy was used to characterize nanoscale ZnO impurities, amine-donor charge-transfer exciplexes, and framework decomposition in samples of MOF-5 prepared by various methods. The combined results cast doubt on previous reports describing MOF-5 as a semiconductor and demonstrate that PL as a tool for characterizing MOF purity possesses advantages such as simplicity, speed, and sensitivity over currently employed powder XRD MOF characterization methods.
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Common genetic variants are significant risk factors for early menopause: results from the Breakthrough Generations Study.
Hum. Mol. Genet.
PUBLISHED: 10-17-2010
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Women become infertile approximately 10 years before menopause, and as more women delay childbirth into their 30s, the number of women who experience infertility is likely to increase. Tests that predict the timing of menopause would allow women to make informed reproductive decisions. Current predictors are only effective just prior to menopause, and there are no long-range indicators. Age at menopause and early menopause (EM) are highly heritable, suggesting a genetic aetiology. Recent genome-wide scans have identified four loci associated with variation in the age of normal menopause (40-60 years). We aimed to determine whether theses loci are also risk factors for EM. We tested the four menopause-associated genetic variants in a cohort of approximately 2000 women with menopause?45 years from the Breakthrough Generations Study (BGS). All four variants significantly increased the odds of having EM. Comparing the 4.5% of individuals with the lowest number of risk alleles (two or three) with the 3.0% with the highest number (eight risk alleles), the odds ratio was 4.1 (95% CI 2.4-7.1, P=4.0×10(-7)). In combination, the four variants discriminated EM cases with a receiver operator characteristic area under the curve of 0.6. Four common genetic variants identified by genome-wide association studies, had a significant impact on the odds of having EM in an independent cohort from the BGS. The discriminative power is still limited, but as more variants are discovered they may be useful for predicting reproductive lifespan.
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Point-of-care diagnostic tests for childhood urinary-tract infection: phase-contrast microscopy for bacteria, stick testing, and counting white blood cells.
J. Clin. Pathol.
PUBLISHED: 09-08-2010
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To evaluate point-of-care testing for childhood urinary-tract infections (UTI).
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Evaluation of a chromogenic culture medium for isolation of Clostridium difficile within 24 hours.
J. Clin. Microbiol.
PUBLISHED: 08-25-2010
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Rapid and effective methods for the isolation of Clostridium difficile from stool samples are desirable to obtain isolates for typing or to facilitate accurate diagnosis of C. difficile-associated diarrhea. We report on the evaluation of a prototype chromogenic medium (ID C. difficile prototype [IDCd]) for isolation of C. difficile. The chromogenic medium was compared using (i) 368 untreated stool samples that were also inoculated onto CLO medium, (ii) 339 stool samples that were subjected to alcohol shock and also inoculated onto five distinct selective agars, and (iii) standardized suspensions of 10 C. difficile ribotypes (untreated and alcohol treated) that were also inoculated onto five distinct selective agars. Two hundred thirty-six isolates of C. difficile were recovered from 368 untreated stool samples, and all but 1 of these strains (99.6%) were recovered on IDCd within 24 h, whereas 74.6% of isolates were recovered on CLO medium after 48 h. Of 339 alcohol-treated stool samples cultured onto IDCd and five other selective agars, C. difficile was recovered from 218 samples using a combination of all media. The use of IDCd allowed recovery of 96.3% of isolates within 24 h, whereas 51 to 83% of isolates were recovered within 24 h using the five other media. Finally, when they were challenged with pure cultures, all 10 ribotypes of C. difficile generated higher colony counts on IDCd irrespective of alcohol pretreatment or duration of incubation. We conclude that IDCd is an effective medium for isolation of C. difficile from stool samples within 24 h.
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Locoregional therapies for hepatocellular carcinoma: which patients are most likely to gain a survival advantage?
J. Gastroenterol. Hepatol.
PUBLISHED: 07-03-2010
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Locoregional therapies for hepatocellular carcinoma (HCC) are considered to confer a survival advantage, however, the patient group that should be targeted is not clearly defined. This study aimed to determine the impact on survival of locoregional therapies compared with supportive care, within prognostic categories as stratified by the Cancer of the Liver Italian Program (CLIP) scoring system.
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Ion transport in nanofluidic funnels.
ACS Nano
PUBLISHED: 07-02-2010
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We report fabrication of nanofluidic channels with asymmetric features (e.g., funnels) that were cast in high modulus poly(dimethylsiloxane) and had well-defined geometries and dimensions. Masters used to cast the funnels were written in the negative tone resist SU-8 by electron beam lithography. Replicated funnels had taper angles of 5, 10, and 20 degrees and were 80 nm wide at the tip, 1 microm wide at the base, and 120 nm deep. The planar format permitted easy coupling of the funnels to microfluidic channels and simultaneous electrical and optical characterization of ion transport. All three designs rectified ion current, and the 5 degrees funnel exhibited the highest rectification ratio. Fluorescence measurements at the funnel base showed that an anionic probe was enriched and depleted in the high and low conductance states, respectively.
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Association analyses of 249,796 individuals reveal 18 new loci associated with body mass index.
Elizabeth K Speliotes, Cristen J Willer, Sonja I Berndt, Keri L Monda, Gudmar Thorleifsson, Anne U Jackson, Hana Lango Allen, Cecilia M Lindgren, Jian'an Luan, Reedik Mägi, Joshua C Randall, Sailaja Vedantam, Thomas W Winkler, Lu Qi, Tsegaselassie Workalemahu, Iris M Heid, Valgerdur Steinthorsdottir, Heather M Stringham, Michael N Weedon, Eleanor Wheeler, Andrew R Wood, Teresa Ferreira, Robert J Weyant, Ayellet V Segrè, Karol Estrada, Liming Liang, James Nemesh, Ju-Hyun Park, Stefan Gustafsson, Tuomas O Kilpeläinen, Jian Yang, Nabila Bouatia-Naji, Tonu Esko, Mary F Feitosa, Zoltan Kutalik, Massimo Mangino, Soumya Raychaudhuri, André Scherag, Albert Vernon Smith, Ryan Welch, Jing Hua Zhao, Katja K Aben, Devin M Absher, Najaf Amin, Anna L Dixon, Eva Fisher, Nicole L Glazer, Michael E Goddard, Nancy L Heard-Costa, Volker Hoesel, Jouke-Jan Hottenga, Asa Johansson, Toby Johnson, Shamika Ketkar, Claudia Lamina, Shengxu Li, Miriam F Moffatt, Richard H Myers, Narisu Narisu, John R B Perry, Marjolein J Peters, Michael Preuss, Samuli Ripatti, Fernando Rivadeneira, Camilla Sandholt, Laura J Scott, Nicholas J Timpson, Jonathan P Tyrer, Sophie van Wingerden, Richard M Watanabe, Charles C White, Fredrik Wiklund, Christina Barlassina, Daniel I Chasman, Matthew N Cooper, John-Olov Jansson, Robert W Lawrence, Niina Pellikka, Inga Prokopenko, Jianxin Shi, Elisabeth Thiering, Helene Alavere, Maria T S Alibrandi, Peter Almgren, Alice M Arnold, Thor Aspelund, Larry D Atwood, Beverley Balkau, Anthony J Balmforth, Amanda J Bennett, Yoav Ben-Shlomo, Richard N Bergman, Sven Bergmann, Heike Biebermann, Alexandra I F Blakemore, Tanja Boes, Lori L Bonnycastle, Stefan R Bornstein, Morris J Brown, Thomas A Buchanan, Fabio Busonero, Harry Campbell, Francesco P Cappuccio, Christine Cavalcanti-Proença, Yii-Der Ida Chen, Chih-Mei Chen, Peter S Chines, Robert Clarke, Lachlan Coin, John Connell, Ian N M Day, Martin den Heijer, Jubao Duan, Shah Ebrahim, Paul Elliott, Roberto Elosua, Gudny Eiriksdottir, Michael R Erdos, Johan G Eriksson, Maurizio F Facheris, Stephan B Felix, Pamela Fischer-Posovszky, Aaron R Folsom, Nele Friedrich, Nelson B Freimer, Mao Fu, Stefan Gaget, Pablo V Gejman, Eco J C Geus, Christian Gieger, Anette P Gjesing, Anuj Goel, Philippe Goyette, Harald Grallert, Jürgen Gräßler, Danielle M Greenawalt, Christopher J Groves, Vilmundur Gudnason, Candace Guiducci, Anna-Liisa Hartikainen, Neelam Hassanali, Alistair S Hall, Aki S Havulinna, Caroline Hayward, Andrew C Heath, Christian Hengstenberg, Andrew A Hicks, Anke Hinney, Albert Hofman, Georg Homuth, Jennie Hui, Wilmar Igl, Carlos Iribarren, Bo Isomaa, Kevin B Jacobs, Ivonne Jarick, Elizabeth Jewell, Ulrich John, Torben Jørgensen, Pekka Jousilahti, Antti Jula, Marika Kaakinen, Eero Kajantie, Lee M Kaplan, Sekar Kathiresan, Johannes Kettunen, Leena Kinnunen, Joshua W Knowles, Ivana Kolčić, Inke R König, Seppo Koskinen, Peter Kovacs, Johanna Kuusisto, Peter Kraft, Kirsti Kvaløy, Jaana Laitinen, Olivier Lantieri, Chiara Lanzani, Lenore J Launer, Cécile Lecoeur, Terho Lehtimäki, Guillaume Lettre, Jianjun Liu, Marja-Liisa Lokki, Mattias Lorentzon, Robert N Luben, Barbara Ludwig, , Paolo Manunta, Diana Marek, Michel Marre, Nicholas G Martin, Wendy L McArdle, Anne McCarthy, Barbara McKnight, Thomas Meitinger, Olle Melander, David Meyre, Kristian Midthjell, Grant W Montgomery, Mario A Morken, Andrew P Morris, Rosanda Mulić, Julius S Ngwa, Mari Nelis, Matt J Neville, Dale R Nyholt, Christopher J O'Donnell, Stephen O'Rahilly, Ken K Ong, Ben Oostra, Guillaume Paré, Alex N Parker, Markus Perola, Irene Pichler, Kirsi H Pietiläinen, Carl G P Platou, Ozren Polašek, Anneli Pouta, Suzanne Rafelt, Olli Raitakari, Nigel W Rayner, Martin Ridderstråle, Winfried Rief, Aimo Ruokonen, Neil R Robertson, Peter Rzehak, Veikko Salomaa, Alan R Sanders, Manjinder S Sandhu, Serena Sanna, Jouko Saramies, Markku J Savolainen, Susann Scherag, Sabine Schipf, Stefan Schreiber, Heribert Schunkert, Kaisa Silander, Juha Sinisalo, David S Siscovick, Jan H Smit, Nicole Soranzo, Ulla Sovio, Jonathan Stephens, Ida Surakka, Amy J Swift, Mari-Liis Tammesoo, Jean-Claude Tardif, Maris Teder-Laving, Tanya M Teslovich, John R Thompson, Brian Thomson, Anke Tönjes, Tiinamaija Tuomi, Joyce B J van Meurs, Gert-Jan van Ommen, Vincent Vatin, Jorma Viikari, Sophie Visvikis-Siest, Veronique Vitart, Carla I G Vogel, Benjamin F Voight, Lindsay L Waite, Henri Wallaschofski, G Bragi Walters, Elisabeth Widén, Susanna Wiegand, Sarah H Wild, Gonneke Willemsen, Daniel R Witte, Jacqueline C Witteman, Jianfeng Xu, Qunyuan Zhang, Lina Zgaga, Andreas Ziegler, Paavo Zitting, John P Beilby, I Sadaf Farooqi, Johannes Hebebrand, Heikki V Huikuri, Alan L James, Mika Kähönen, Douglas F Levinson, Fabio Macciardi, Markku S Nieminen, Claes Ohlsson, Lyle J Palmer, Paul M Ridker, Michael Stumvoll, Jacques S Beckmann, Heiner Boeing, Eric Boerwinkle, Dorret I Boomsma, Mark J Caulfield, Stephen J Chanock, Francis S Collins, L Adrienne Cupples, George Davey Smith, Jeanette Erdmann, Philippe Froguel, Henrik Grönberg, Ulf Gyllensten, Per Hall, Torben Hansen, Tamara B Harris, Andrew T Hattersley, Richard B Hayes, Joachim Heinrich, Frank B Hu, Kristian Hveem, Thomas Illig, Marjo-Riitta Järvelin, Jaakko Kaprio, Fredrik Karpe, Kay-Tee Khaw, Lambertus A Kiemeney, Heiko Krude, Markku Laakso, Debbie A Lawlor, Andres Metspalu, Patricia B Munroe, Willem H Ouwehand, Oluf Pedersen, Brenda W Penninx, Annette Peters, Peter P Pramstaller, Thomas Quertermous, Thomas Reinehr, Aila Rissanen, Igor Rudan, Nilesh J Samani, Peter E H Schwarz, Alan R Shuldiner, Timothy D Spector, Jaakko Tuomilehto, Manuela Uda, André Uitterlinden, Timo T Valle, Martin Wabitsch, Gérard Waeber, Nicholas J Wareham, Hugh Watkins, James F Wilson, Alan F Wright, M Carola Zillikens, Nilanjan Chatterjee, Steven A McCarroll, Shaun Purcell, Eric E Schadt, Peter M Visscher, Themistocles L Assimes, Ingrid B Borecki, Panos Deloukas, Caroline S Fox, Leif C Groop, Talin Haritunians, David J Hunter, Robert C Kaplan, Karen L Mohlke, Jeffrey R O'Connell, Leena Peltonen, David Schlessinger, David P Strachan, Cornelia M van Duijn, H-Erich Wichmann, Timothy M Frayling, Unnur Thorsteinsdottir, Gonçalo R Abecasis, Inês Barroso, Michael Boehnke, Kari Stefansson, Kari E North, Mark I McCarthy, Joel N Hirschhorn, Erik Ingelsson, Ruth J F Loos.
Nat. Genet.
PUBLISHED: 05-13-2010
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Obesity is globally prevalent and highly heritable, but its underlying genetic factors remain largely elusive. To identify genetic loci for obesity susceptibility, we examined associations between body mass index and ? 2.8 million SNPs in up to 123,865 individuals with targeted follow up of 42 SNPs in up to 125,931 additional individuals. We confirmed 14 known obesity susceptibility loci and identified 18 new loci associated with body mass index (P < 5 × 10??), one of which includes a copy number variant near GPRC5B. Some loci (at MC4R, POMC, SH2B1 and BDNF) map near key hypothalamic regulators of energy balance, and one of these loci is near GIPR, an incretin receptor. Furthermore, genes in other newly associated loci may provide new insights into human body weight regulation.
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Thirty new loci for age at menarche identified by a meta-analysis of genome-wide association studies.
Cathy E Elks, John R B Perry, Patrick Sulem, Daniel I Chasman, Nora Franceschini, Chunyan He, Kathryn L Lunetta, Jenny A Visser, Enda M Byrne, Diana L Cousminer, Daniel F Gudbjartsson, Tonu Esko, Bjarke Feenstra, Jouke-Jan Hottenga, Daniel L Koller, Zoltan Kutalik, Peng Lin, Massimo Mangino, Mara Marongiu, Patrick F McArdle, Albert V Smith, Lisette Stolk, Sophie H van Wingerden, Jing Hua Zhao, Eva Albrecht, Tanguy Corre, Erik Ingelsson, Caroline Hayward, Patrik K E Magnusson, Erin N Smith, Shelia Ulivi, Nicole M Warrington, Lina Zgaga, Helen Alavere, Najaf Amin, Thor Aspelund, Stefania Bandinelli, Inês Barroso, Gerald S Berenson, Sven Bergmann, Hannah Blackburn, Eric Boerwinkle, Julie E Buring, Fabio Busonero, Harry Campbell, Stephen J Chanock, Wei Chen, Marilyn C Cornelis, David Couper, Andrea D Coviello, Pio D'Adamo, Ulf de Faire, Eco J C de Geus, Panos Deloukas, Angela Döring, George Davey Smith, Douglas F Easton, Gudny Eiriksdottir, Valur Emilsson, Johan Eriksson, Luigi Ferrucci, Aaron R Folsom, Tatiana Foroud, Melissa Garcia, Paolo Gasparini, Frank Geller, Christian Gieger, , Vilmundur Gudnason, Per Hall, Susan E Hankinson, Liana Ferreli, Andrew C Heath, Dena G Hernandez, Albert Hofman, Frank B Hu, Thomas Illig, Marjo-Riitta Järvelin, Andrew D Johnson, David Karasik, Kay-Tee Khaw, Douglas P Kiel, Tuomas O Kilpeläinen, Ivana Kolčić, Peter Kraft, Lenore J Launer, Joop S E Laven, Shengxu Li, Jianjun Liu, Daniel Levy, Nicholas G Martin, Wendy L McArdle, Mads Melbye, Vincent Mooser, Jeffrey C Murray, Sarah S Murray, Michael A Nalls, Pau Navarro, Mari Nelis, Andrew R Ness, Kate Northstone, Ben A Oostra, Munro Peacock, Lyle J Palmer, Aarno Palotie, Guillaume Paré, Alex N Parker, Nancy L Pedersen, Leena Peltonen, Craig E Pennell, Paul Pharoah, Ozren Polašek, Andrew S Plump, Anneli Pouta, Eleonora Porcu, Thorunn Rafnar, John P Rice, Susan M Ring, Fernando Rivadeneira, Igor Rudan, Cinzia Sala, Veikko Salomaa, Serena Sanna, David Schlessinger, Nicholas J Schork, Angelo Scuteri, Ayellet V Segrè, Alan R Shuldiner, Nicole Soranzo, Ulla Sovio, Sathanur R Srinivasan, David P Strachan, Mar-Liis Tammesoo, Emmi Tikkanen, Daniela Toniolo, Kim Tsui, Laufey Tryggvadóttir, Jonathon Tyrer, Manuela Uda, Rob M Van Dam, Joyce B J van Meurs, Peter Vollenweider, Gérard Waeber, Nicholas J Wareham, Dawn M Waterworth, Michael N Weedon, H Erich Wichmann, Gonneke Willemsen, James F Wilson, Alan F Wright, Lauren Young, Guangju Zhai, Wei Vivian Zhuang, Laura J Bierut, Dorret I Boomsma, Heather A Boyd, Laura Crisponi, Ellen W Demerath, Cornelia M van Duijn, Michael J Econs, Tamara B Harris, David J Hunter, Ruth J F Loos, Andres Metspalu, Grant W Montgomery, Paul M Ridker, Tim D Spector, Elizabeth A Streeten, Kari Stefansson, Unnur Thorsteinsdottir, André G Uitterlinden, Elisabeth Widén, Joanne M Murabito, Ken K Ong, Anna Murray.
Nat. Genet.
PUBLISHED: 05-10-2010
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To identify loci for age at menarche, we performed a meta-analysis of 32 genome-wide association studies in 87,802 women of European descent, with replication in up to 14,731 women. In addition to the known loci at LIN28B (P = 5.4 × 10???) and 9q31.2 (P = 2.2 × 10?³³), we identified 30 new menarche loci (all P < 5 × 10??) and found suggestive evidence for a further 10 loci (P < 1.9 × 10??). The new loci included four previously associated with body mass index (in or near FTO, SEC16B, TRA2B and TMEM18), three in or near other genes implicated in energy homeostasis (BSX, CRTC1 and MCHR2) and three in or near genes implicated in hormonal regulation (INHBA, PCSK2 and RXRG). Ingenuity and gene-set enrichment pathway analyses identified coenzyme A and fatty acid biosynthesis as biological processes related to menarche timing.
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Meta-analysis identifies 13 new loci associated with waist-hip ratio and reveals sexual dimorphism in the genetic basis of fat distribution.
Iris M Heid, Anne U Jackson, Joshua C Randall, Thomas W Winkler, Lu Qi, Valgerdur Steinthorsdottir, Gudmar Thorleifsson, M Carola Zillikens, Elizabeth K Speliotes, Reedik Mägi, Tsegaselassie Workalemahu, Charles C White, Nabila Bouatia-Naji, Tamara B Harris, Sonja I Berndt, Erik Ingelsson, Cristen J Willer, Michael N Weedon, Jian'an Luan, Sailaja Vedantam, Tonu Esko, Tuomas O Kilpeläinen, Zoltan Kutalik, Shengxu Li, Keri L Monda, Anna L Dixon, Christopher C Holmes, Lee M Kaplan, Liming Liang, Josine L Min, Miriam F Moffatt, Cliona Molony, George Nicholson, Eric E Schadt, Krina T Zondervan, Mary F Feitosa, Teresa Ferreira, Hana Lango Allen, Robert J Weyant, Eleanor Wheeler, Andrew R Wood, , Karol Estrada, Michael E Goddard, Guillaume Lettre, Massimo Mangino, Dale R Nyholt, Shaun Purcell, Albert Vernon Smith, Peter M Visscher, Jian Yang, Steven A McCarroll, James Nemesh, Benjamin F Voight, Devin Absher, Najaf Amin, Thor Aspelund, Lachlan Coin, Nicole L Glazer, Caroline Hayward, Nancy L Heard-Costa, Jouke-Jan Hottenga, Asa Johansson, Toby Johnson, Marika Kaakinen, Karen Kapur, Shamika Ketkar, Joshua W Knowles, Peter Kraft, Aldi T Kraja, Claudia Lamina, Michael F Leitzmann, Barbara McKnight, Andrew P Morris, Ken K Ong, John R B Perry, Marjolein J Peters, Ozren Polašek, Inga Prokopenko, Nigel W Rayner, Samuli Ripatti, Fernando Rivadeneira, Neil R Robertson, Serena Sanna, Ulla Sovio, Ida Surakka, Alexander Teumer, Sophie van Wingerden, Veronique Vitart, Jing Hua Zhao, Christine Cavalcanti-Proença, Peter S Chines, Eva Fisher, Jennifer R Kulzer, Cécile Lecoeur, Narisu Narisu, Camilla Sandholt, Laura J Scott, Kaisa Silander, Klaus Stark, Mari-Liis Tammesoo, Tanya M Teslovich, Nicholas John Timpson, Richard M Watanabe, Ryan Welch, Daniel I Chasman, Matthew N Cooper, John-Olov Jansson, Johannes Kettunen, Robert W Lawrence, Niina Pellikka, Markus Perola, Liesbeth Vandenput, Helene Alavere, Peter Almgren, Larry D Atwood, Amanda J Bennett, Reiner Biffar, Lori L Bonnycastle, Stefan R Bornstein, Thomas A Buchanan, Harry Campbell, Ian N M Day, Mariano Dei, Marcus Dörr, Paul Elliott, Michael R Erdos, Johan G Eriksson, Nelson B Freimer, Mao Fu, Stefan Gaget, Eco J C Geus, Anette P Gjesing, Harald Grallert, Jürgen Gräßler, Christopher J Groves, Candace Guiducci, Anna-Liisa Hartikainen, Neelam Hassanali, Aki S Havulinna, Karl-Heinz Herzig, Andrew A Hicks, Jennie Hui, Wilmar Igl, Pekka Jousilahti, Antti Jula, Eero Kajantie, Leena Kinnunen, Ivana Kolčić, Seppo Koskinen, Peter Kovacs, Heyo K Kroemer, Vjekoslav Krželj, Johanna Kuusisto, Kirsti Kvaloy, Jaana Laitinen, Olivier Lantieri, G Mark Lathrop, Marja-Liisa Lokki, Robert N Luben, Barbara Ludwig, Wendy L McArdle, Anne McCarthy, Mario A Morken, Mari Nelis, Matt J Neville, Guillaume Paré, Alex N Parker, John F Peden, Irene Pichler, Kirsi H Pietiläinen, Carl G P Platou, Anneli Pouta, Martin Ridderstråle, Nilesh J Samani, Jouko Saramies, Juha Sinisalo, Jan H Smit, Rona J Strawbridge, Heather M Stringham, Amy J Swift, Maris Teder-Laving, Brian Thomson, Gianluca Usala, Joyce B J van Meurs, Gert-Jan van Ommen, Vincent Vatin, Claudia B Volpato, Henri Wallaschofski, G Bragi Walters, Elisabeth Widén, Sarah H Wild, Gonneke Willemsen, Daniel R Witte, Lina Zgaga, Paavo Zitting, John P Beilby, Alan L James, Mika Kähönen, Terho Lehtimäki, Markku S Nieminen, Claes Ohlsson, Lyle J Palmer, Olli Raitakari, Paul M Ridker, Michael Stumvoll, Anke Tönjes, Jorma Viikari, Beverley Balkau, Yoav Ben-Shlomo, Richard N Bergman, Heiner Boeing, George Davey Smith, Shah Ebrahim, Philippe Froguel, Torben Hansen, Christian Hengstenberg, Kristian Hveem, Bo Isomaa, Torben Jørgensen, Fredrik Karpe, Kay-Tee Khaw, Markku Laakso, Debbie A Lawlor, Michel Marre, Thomas Meitinger, Andres Metspalu, Kristian Midthjell, Oluf Pedersen, Veikko Salomaa, Peter E H Schwarz, Tiinamaija Tuomi, Jaakko Tuomilehto, Timo T Valle, Nicholas J Wareham, Alice M Arnold, Jacques S Beckmann, Sven Bergmann, Eric Boerwinkle, Dorret I Boomsma, Mark J Caulfield, Francis S Collins, Gudny Eiriksdottir, Vilmundur Gudnason, Ulf Gyllensten, Anders Hamsten, Andrew T Hattersley, Albert Hofman, Frank B Hu, Thomas Illig, Carlos Iribarren, Marjo-Riitta Järvelin, W H Linda Kao, Jaakko Kaprio, Lenore J Launer, Patricia B Munroe, Ben Oostra, Brenda W Penninx, Peter P Pramstaller, Bruce M Psaty, Thomas Quertermous, Aila Rissanen, Igor Rudan, Alan R Shuldiner, Nicole Soranzo, Timothy D Spector, Ann-Christine Syvänen, Manuela Uda, André Uitterlinden, Henry Völzke, Peter Vollenweider, James F Wilson, Jacqueline C Witteman, Alan F Wright, Gonçalo R Abecasis, Michael Boehnke, Ingrid B Borecki, Panos Deloukas, Timothy M Frayling, Leif C Groop, Talin Haritunians, David J Hunter, Robert C Kaplan, Kari E North, Jeffrey R O'Connell, Leena Peltonen, David Schlessinger, David P Strachan, Joel N Hirschhorn, Themistocles L Assimes, H-Erich Wichmann, Unnur Thorsteinsdottir, Cornelia M van Duijn, Kari Stefansson, L Adrienne Cupples, Ruth J F Loos, Inês Barroso, Mark I McCarthy, Caroline S Fox, Karen L Mohlke, Cecilia M Lindgren.
Nat. Genet.
PUBLISHED: 05-06-2010
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Waist-hip ratio (WHR) is a measure of body fat distribution and a predictor of metabolic consequences independent of overall adiposity. WHR is heritable, but few genetic variants influencing this trait have been identified. We conducted a meta-analysis of 32 genome-wide association studies for WHR adjusted for body mass index (comprising up to 77,167 participants), following up 16 loci in an additional 29 studies (comprising up to 113,636 subjects). We identified 13 new loci in or near RSPO3, VEGFA, TBX15-WARS2, NFE2L3, GRB14, DNM3-PIGC, ITPR2-SSPN, LY86, HOXC13, ADAMTS9, ZNRF3-KREMEN1, NISCH-STAB1 and CPEB4 (P = 1.9 × 10?? to P = 1.8 × 10???) and the known signal at LYPLAL1. Seven of these loci exhibited marked sexual dimorphism, all with a stronger effect on WHR in women than men (P for sex difference = 1.9 × 10?³ to P = 1.2 × 10?¹³). These findings provide evidence for multiple loci that modulate body fat distribution independent of overall adiposity and reveal strong gene-by-sex interactions.
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Hundreds of variants clustered in genomic loci and biological pathways affect human height.
Hana Lango Allen, Karol Estrada, Guillaume Lettre, Sonja I Berndt, Michael N Weedon, Fernando Rivadeneira, Cristen J Willer, Anne U Jackson, Sailaja Vedantam, Soumya Raychaudhuri, Teresa Ferreira, Andrew R Wood, Robert J Weyant, Ayellet V Segrè, Elizabeth K Speliotes, Eleanor Wheeler, Nicole Soranzo, Ju-Hyun Park, Jian Yang, Daniel Gudbjartsson, Nancy L Heard-Costa, Joshua C Randall, Lu Qi, Albert Vernon Smith, Reedik Mägi, Tomi Pastinen, Liming Liang, Iris M Heid, Jian'an Luan, Gudmar Thorleifsson, Thomas W Winkler, Michael E Goddard, Ken Sin Lo, Cameron Palmer, Tsegaselassie Workalemahu, Yurii S Aulchenko, Asa Johansson, M Carola Zillikens, Mary F Feitosa, Tonu Esko, Toby Johnson, Shamika Ketkar, Peter Kraft, Massimo Mangino, Inga Prokopenko, Devin Absher, Eva Albrecht, Florian Ernst, Nicole L Glazer, Caroline Hayward, Jouke-Jan Hottenga, Kevin B Jacobs, Joshua W Knowles, Zoltan Kutalik, Keri L Monda, Ozren Polašek, Michael Preuss, Nigel W Rayner, Neil R Robertson, Valgerdur Steinthorsdottir, Jonathan P Tyrer, Benjamin F Voight, Fredrik Wiklund, Jianfeng Xu, Jing Hua Zhao, Dale R Nyholt, Niina Pellikka, Markus Perola, John R B Perry, Ida Surakka, Mari-Liis Tammesoo, Elizabeth L Altmaier, Najaf Amin, Thor Aspelund, Tushar Bhangale, Gabrielle Boucher, Daniel I Chasman, Constance Chen, Lachlan Coin, Matthew N Cooper, Anna L Dixon, Quince Gibson, Elin Grundberg, Ke Hao, M Juhani Junttila, Lee M Kaplan, Johannes Kettunen, Inke R König, Tony Kwan, Robert W Lawrence, Douglas F Levinson, Mattias Lorentzon, Barbara McKnight, Andrew P Morris, Martina Müller, Julius Suh Ngwa, Shaun Purcell, Suzanne Rafelt, Rany M Salem, Erika Salvi, Serena Sanna, Jianxin Shi, Ulla Sovio, John R Thompson, Michael C Turchin, Liesbeth Vandenput, Dominique J Verlaan, Veronique Vitart, Charles C White, Andreas Ziegler, Peter Almgren, Anthony J Balmforth, Harry Campbell, Lorena Citterio, Alessandro De Grandi, Anna Dominiczak, Jubao Duan, Paul Elliott, Roberto Elosua, Johan G Eriksson, Nelson B Freimer, Eco J C Geus, Nicola Glorioso, Shen Haiqing, Anna-Liisa Hartikainen, Aki S Havulinna, Andrew A Hicks, Jennie Hui, Wilmar Igl, Thomas Illig, Antti Jula, Eero Kajantie, Tuomas O Kilpeläinen, Markku Koiranen, Ivana Kolčić, Seppo Koskinen, Peter Kovacs, Jaana Laitinen, Jianjun Liu, Marja-Liisa Lokki, Ana Marušić, Andrea Maschio, Thomas Meitinger, Antonella Mulas, Guillaume Paré, Alex N Parker, John F Peden, Astrid Petersmann, Irene Pichler, Kirsi H Pietiläinen, Anneli Pouta, Martin Ridderstråle, Jerome I Rotter, Jennifer G Sambrook, Alan R Sanders, Carsten Oliver Schmidt, Juha Sinisalo, Jan H Smit, Heather M Stringham, G Bragi Walters, Elisabeth Widén, Sarah H Wild, Gonneke Willemsen, Laura Zagato, Lina Zgaga, Paavo Zitting, Helene Alavere, Martin Farrall, Wendy L McArdle, Mari Nelis, Marjolein J Peters, Samuli Ripatti, Joyce B J van Meurs, Katja K Aben, Kristin G Ardlie, Jacques S Beckmann, John P Beilby, Richard N Bergman, Sven Bergmann, Francis S Collins, Daniele Cusi, Martin den Heijer, Gudny Eiriksdottir, Pablo V Gejman, Alistair S Hall, Anders Hamsten, Heikki V Huikuri, Carlos Iribarren, Mika Kähönen, Jaakko Kaprio, Sekar Kathiresan, Lambertus Kiemeney, Thomas Kocher, Lenore J Launer, Terho Lehtimäki, Olle Melander, Tom H Mosley, Arthur W Musk, Markku S Nieminen, Christopher J O'Donnell, Claes Ohlsson, Ben Oostra, Lyle J Palmer, Olli Raitakari, Paul M Ridker, John D Rioux, Aila Rissanen, Carlo Rivolta, Heribert Schunkert, Alan R Shuldiner, David S Siscovick, Michael Stumvoll, Anke Tönjes, Jaakko Tuomilehto, Gert-Jan van Ommen, Jorma Viikari, Andrew C Heath, Nicholas G Martin, Grant W Montgomery, Michael A Province, Manfred Kayser, Alice M Arnold, Larry D Atwood, Eric Boerwinkle, Stephen J Chanock, Panos Deloukas, Christian Gieger, Henrik Grönberg, Per Hall, Andrew T Hattersley, Christian Hengstenberg, Wolfgang Hoffman, G Mark Lathrop, Veikko Salomaa, Stefan Schreiber, Manuela Uda, Dawn Waterworth, Alan F Wright, Themistocles L Assimes, Inês Barroso, Albert Hofman, Karen L Mohlke, Dorret I Boomsma, Mark J Caulfield, L Adrienne Cupples, Jeanette Erdmann, Caroline S Fox, Vilmundur Gudnason, Ulf Gyllensten, Tamara B Harris, Richard B Hayes, Marjo-Riitta Järvelin, Vincent Mooser, Patricia B Munroe, Willem H Ouwehand, Brenda W Penninx, Peter P Pramstaller, Thomas Quertermous, Igor Rudan, Nilesh J Samani, Timothy D Spector, Henry Völzke, Hugh Watkins, James F Wilson, Leif C Groop, Talin Haritunians, Frank B Hu, Robert C Kaplan, Andres Metspalu, Kari E North, David Schlessinger, Nicholas J Wareham, David J Hunter, Jeffrey R O'Connell, David P Strachan, H-Erich Wichmann, Ingrid B Borecki, Cornelia M van Duijn, Eric E Schadt, Unnur Thorsteinsdottir, Leena Peltonen, André G Uitterlinden, Peter M Visscher, Nilanjan Chatterjee, Ruth J F Loos, Michael Boehnke, Mark I McCarthy, Erik Ingelsson, Cecilia M Lindgren, Gonçalo R Abecasis, Kari Stefansson, Timothy M Frayling, Joel N Hirschhorn.
Nature
PUBLISHED: 04-23-2010
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Most common human traits and diseases have a polygenic pattern of inheritance: DNA sequence variants at many genetic loci influence the phenotype. Genome-wide association (GWA) studies have identified more than 600 variants associated with human traits, but these typically explain small fractions of phenotypic variation, raising questions about the use of further studies. Here, using 183,727 individuals, we show that hundreds of genetic variants, in at least 180 loci, influence adult height, a highly heritable and classic polygenic trait. The large number of loci reveals patterns with important implications for genetic studies of common human diseases and traits. First, the 180 loci are not random, but instead are enriched for genes that are connected in biological pathways (P = 0.016) and that underlie skeletal growth defects (P?
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Functional assays for hematopoietic stem cell self-renewal.
Methods Mol. Biol.
PUBLISHED: 03-26-2010
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Stem cells are defined by the ability to self-renew. Specific functional assays have been developed for the rigorous identification and quantification of hematopoietic stem cells (HSCs), making these cells the benchmark in studies of self-renewal. Here, we review the theory behind these functional stem cell tests and discuss important considerations in choosing and designing these assays. Finally, we provide a basic protocol for the serial-dilution assay, a quantitative assay for HSCs, from which individual researchers can construct their own customized protocols utilizing the guidelines discussed.
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Primary bronchial epithelial cell culture from explanted cystic fibrosis lungs.
Exp. Lung Res.
PUBLISHED: 03-09-2010
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Lung disease is responsible for more than 95% of morbidity and mortality in cystic fibrosis. The exact pathogenesis of cystic fibrosis lung disease remains poorly understood. Experimental models are therefore vital for use in research. Animal models and immortalized cell lines both have inherent limitations. Explanted lungs removed from people with cystic fibrosis at the time of transplantation represent a potentially valuable but technically and logistically challenging source of primary cystic fibrosis bronchial epithelial cells. In this study, pieces of segmental bronchus from explanted lungs were treated with patient-specific antimicrobials prior to isolation of bronchial epithelial cells. Cultured cells were characterized by their morphology under light microscopy, cytokeratin and hematoxylin-eosin staining, and electrophysiological profile. Primary bronchial epithelial cells were successfully cultured from 15 of 22 patients attempted. The cells exhibited typical epithelial morphology, staining for cytokeratin, lack of responsiveness to forskolin treatment, and remained viable after storage in liquid nitrogen. Seven unsuccessful cultures failed due to early infection with bacteria known to colonize the airways pretransplant. The results show that primary bronchial epithelial cell culture is possible from explanted cystic fibrosis lungs. This provides an important cellular model to elucidate the pathogenic mechanisms in cystic fibrosis lung disease and to investigate potential therapeutic targets.
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Genome-wide association study of CNVs in 16,000 cases of eight common diseases and 3,000 shared controls.
, Nick Craddock, Matthew E Hurles, Niall Cardin, Richard D Pearson, Vincent Plagnol, Samuel Robson, Damjan Vukcevic, Chris Barnes, Donald F Conrad, Eleni Giannoulatou, Chris Holmes, Jonathan L Marchini, Kathy Stirrups, Martin D Tobin, Louise V Wain, Chris Yau, Jan Aerts, Tariq Ahmad, T Daniel Andrews, Hazel Arbury, Anthony Attwood, Adam Auton, Stephen G Ball, Anthony J Balmforth, Jeffrey C Barrett, Inês Barroso, Anne Barton, Amanda J Bennett, Sanjeev Bhaskar, Katarzyna Blaszczyk, John Bowes, Oliver J Brand, Peter S Braund, Francesca Bredin, Gerome Breen, Morris J Brown, Ian N Bruce, Jaswinder Bull, Oliver S Burren, John Burton, Jake Byrnes, Sian Caesar, Chris M Clee, Alison J Coffey, John M C Connell, Jason D Cooper, Anna F Dominiczak, Kate Downes, Hazel E Drummond, Darshna Dudakia, Andrew Dunham, Bernadette Ebbs, Diana Eccles, Sarah Edkins, Cathryn Edwards, Anna Elliot, Paul Emery, David M Evans, Gareth Evans, Steve Eyre, Anne Farmer, I Nicol Ferrier, Lars Feuk, Tomas Fitzgerald, Edward Flynn, Alistair Forbes, Liz Forty, Jayne A Franklyn, Rachel M Freathy, Polly Gibbs, Paul Gilbert, Omer Gokumen, Katherine Gordon-Smith, Emma Gray, Elaine Green, Chris J Groves, Detelina Grozeva, Rhian Gwilliam, Anita Hall, Naomi Hammond, Matt Hardy, Pile Harrison, Neelam Hassanali, Husam Hebaishi, Sarah Hines, Anne Hinks, Graham A Hitman, Lynne Hocking, Eleanor Howard, Philip Howard, Joanna M M Howson, Debbie Hughes, Sarah Hunt, John D Isaacs, Mahim Jain, Derek P Jewell, Toby Johnson, Jennifer D Jolley, Ian R Jones, Lisa A Jones, George Kirov, Cordelia F Langford, Hana Lango-Allen, G Mark Lathrop, James Lee, Kate L Lee, Charlie Lees, Kevin Lewis, Cecilia M Lindgren, Meeta Maisuria-Armer, Julian Maller, John Mansfield, Paul Martin, Dunecan C O Massey, Wendy L McArdle, Peter McGuffin, Kirsten E McLay, Alex Mentzer, Michael L Mimmack, Ann E Morgan, Andrew P Morris, Craig Mowat, Simon Myers, William Newman, Elaine R Nimmo, Michael C O'Donovan, Abiodun Onipinla, Ifejinelo Onyiah, Nigel R Ovington, Michael J Owen, Kimmo Palin, Kirstie Parnell, David Pernet, John R B Perry, Anne Phillips, Dalila Pinto, Natalie J Prescott, Inga Prokopenko, Michael A Quail, Suzanne Rafelt, Nigel W Rayner, Richard Redon, David M Reid, Renwick, Susan M Ring, Neil Robertson, Ellie Russell, David St Clair, Jennifer G Sambrook, Jeremy D Sanderson, Helen Schuilenburg, Carol E Scott, Richard Scott, Sheila Seal, Sue Shaw-Hawkins, Beverley M Shields, Matthew J Simmonds, Debbie J Smyth, Elilan Somaskantharajah, Katarina Spanova, Sophia Steer, Jonathan Stephens, Helen E Stevens, Millicent A Stone, Zhan Su, Deborah P M Symmons, John R Thompson, Wendy Thomson, Mary E Travers, Clare Turnbull, Armand Valsesia, Mark Walker, Neil M Walker, Chris Wallace, Margaret Warren-Perry, Nicholas A Watkins, John Webster, Michael N Weedon, Anthony G Wilson, Matthew Woodburn, B Paul Wordsworth, Allan H Young, Eleftheria Zeggini, Nigel P Carter, Timothy M Frayling, Charles Lee, Gil McVean, Patricia B Munroe, Aarno Palotie, Stephen J Sawcer, Stephen W Scherer, David P Strachan, Chris Tyler-Smith, Matthew A Brown, Paul R Burton, Mark J Caulfield, Alastair Compston, Martin Farrall, Stephen C L Gough, Alistair S Hall, Andrew T Hattersley, Adrian V S Hill, Christopher G Mathew, Marcus Pembrey, Jack Satsangi, Michael R Stratton, Jane Worthington, Panos Deloukas, Audrey Duncanson, Dominic P Kwiatkowski, Mark I McCarthy, Willem Ouwehand, Miles Parkes, Nazneen Rahman, John A Todd, Nilesh J Samani, Peter Donnelly.
Nature
PUBLISHED: 03-05-2010
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Copy number variants (CNVs) account for a major proportion of human genetic polymorphism and have been predicted to have an important role in genetic susceptibility to common disease. To address this we undertook a large, direct genome-wide study of association between CNVs and eight common human diseases. Using a purpose-designed array we typed approximately 19,000 individuals into distinct copy-number classes at 3,432 polymorphic CNVs, including an estimated approximately 50% of all common CNVs larger than 500 base pairs. We identified several biological artefacts that lead to false-positive associations, including systematic CNV differences between DNAs derived from blood and cell lines. Association testing and follow-up replication analyses confirmed three loci where CNVs were associated with disease-IRGM for Crohns disease, HLA for Crohns disease, rheumatoid arthritis and type 1 diabetes, and TSPAN8 for type 2 diabetes-although in each case the locus had previously been identified in single nucleotide polymorphism (SNP)-based studies, reflecting our observation that most common CNVs that are well-typed on our array are well tagged by SNPs and so have been indirectly explored through SNP studies. We conclude that common CNVs that can be typed on existing platforms are unlikely to contribute greatly to the genetic basis of common human diseases.
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Alterations in LMTK2, MSMB and HNF1B gene expression are associated with the development of prostate cancer.
BMC Cancer
PUBLISHED: 03-04-2010
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Genome wide association studies (GWAS) have identified several genetic variants that are associated with prostate cancer. Most of these variants, like other GWAS association signals, are located in non-coding regions of potential candidate genes, and thus could act at the level of the mRNA transcript.
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Redefining urinary tract infections by bacterial colony counts.
Pediatrics
PUBLISHED: 01-25-2010
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To determine the best urinary bacterial concentration to diagnose urine infections.
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