Search results for "Meta-"

Sex differences in the prevalence of Helicobacter pylori infection: an individual participant data pooled analysis (StoP Project)

2019

Background Helicobacter pylori (H. pylori) infection is more frequent among men, though the magnitude of the association might be inaccurate due to potential misclassification of lifetime infection and publication bias. Moreover, infection is common, and most studies are cross-sectional. Thus, prevalence ratios (PRs) may be easier to interpret than odds ratios (ORs). Aim The aim of this study was to quantify the association between sex and H. pylori infection using controls from 14 studies from the Stomach Cancer Pooling (StoP) Project. Participants and methods H. pylori infection was defined based on IgG serum antibody titers or multiplex serology. Participants were also classified as infe…

Biaix de publicació en meta-anàlisi: revisió dels mètodes de detecció i avaluació

2018

espanolLos estudios de meta-analisis se consideran actualmente como las mejores herramientas para sintetizar las pruebas cientificas respecto a que tratamientos, intervenciones o programas de prevencion deberian aplicar para un determinado problema psicologico. Sin embargo, los estudios de meta-analisis tambien estan sometidos a limitaciones, como el sesgo de publicacion. Asi pues, los psicologos deben saber como pueden hacer valoraciones criticas. El objetivo de este articulo es presentar los metodos de deteccion del sesgo de publicacion mas utilizados, asi como alguna guia orientativa sobre como hacer una lectura critica. Los procedimientos mas utilizados para la valoracion del sesgo de p…

CD45 and multiple sclerosis: the exon 4 C77G polymorphism (additional studies and meta-analysis) and new markers

2003

We re-evaluated the association with multiple sclerosis (MS) of the C77G splicing regulatory variation in the CD45 gene and screened for new mutations the three alternatively spliced exons (#4, 5 and 6). No association with C77G was detected in two groups of patients (total=448) and controls (total=559) from Northern and Southern Italy. When excluding the first published study indicating a positive association, a meta-analysis of the five further studies conducted to date (including the present one) led to a non-significant combined odds ratio (OR) of 1.11. None of the four newly identified nucleotide substitutions, namely C77T (Pro59Pro) in exon 4, G69C (Asp121His) in exon 5, T127A (Ile187…

Pro-Inflammatory Genetic Markers of Atherosclerosis

2013

Atherosclerosis (AS) is a chronic, progressive, multifactorial disease mostly affecting large and medium-sized elastic and muscular arteries. It has formerly been considered a bland lipid storage disease. Currently, multiple independent pathways of evidence suggest this pathological condition is a peculiar form of inflammation, triggered by cholesterol-rich lipoproteins and influenced both by environmental and genetic factors. The Human Genome Project opened up the opportunity to dissect complex human traits and to understand basic pathways of multifactorial diseases such as AS. Population-based association studies have emerged as powerful tools for examining genes with a role in common mul…

Low vitamin D levels increase the risk of type 2 diabetes in older adults: A systematic review and meta-analysis

2017

Low serum levels of 25 hydroxyvitamin D (25OHD) (hypovitaminosis D) is common in older adults and associated with several negative outcomes. The association between hypovitaminosis D and diabetes in older adults is equivocal, however. We conducted a meta-analysis investigating if hypovitaminosis D is associated with diabetes in prospective studies among older participants. Two investigators systematically searched major electronic databases, from inception until 10/07/2016. The cumulative incidence of diabetes among groups was estimated according to baseline serum 25OHD levels. Random effect models were used to assess the association between hypovitaminosis D and diabetes at follow-up. From…

Internal limiting membrane peeling versus no peeling during primary vitrectomy for rhegmatogenous retinal detachment: A systematic review and meta-an…

2018

Background Internal limiting membrane (ILM) peeling during primary vitrectomy for rhegmatogenous retinal detachment (RRD) prevents the formation of postoperative macular epiretinal membrane (ERM). However, studies that compared vitrectomy with and without ILM peeling for RRD, have reported controversial outcomes. Objective To assess the efficacy of ILM peeling versus non-ILM peeling during vitrectomy for RRD by a systematic review and meta-analysis of published studies. Methods PubMed, Medline, Web of Science, Embase databases, and the Cochrane Library were searched up to April 2018 to identify studies that compared primary vitrectomy with and without ILM peeling for RRD with at least six m…

Meta-analysis of genome-wide linkage scans of attention deficit hyperactivity disorder

2008

Contains fulltext : 69243.pdf (Publisher’s version ) (Closed access) Genetic contribution to the development of attention deficit hyperactivity disorder (ADHD) is well established. Seven independent genome-wide linkage scans have been performed to map loci that increase the risk for ADHD. Although significant linkage signals were identified in some of the studies, there has been limited replications between the various independent datasets. The current study gathered the results from all seven of the ADHD linkage scans and performed a Genome Scan Meta Analysis (GSMA) to identify the genomic region with most consistent linkage evidence across the studies. Genome-wide significant linkage (P(S…

2012

More than 800 published genetic association studies have implicated dozens of potential risk loci in Parkinson’s disease (PD). To facilitate the interpretation of these findings, we have created a dedicated online resource, PDGene, that comprehensively collects and meta-analyzes all published studies in the field. A systematic literature screen of ,27,000 articles yielded 828 eligible articles from which relevant data were extracted. In addition, individual-level data from three publicly available genome-wide association studies (GWAS) were obtained and subjected to genotype imputation and analysis. Overall, we performed meta-analyses on more than seven million polymorphisms originating eit…

A large cross-ancestry meta-analysis of genome-wide association studies identifies 69 novel risk loci for primary open-angle glaucoma and includes a …

2020

AbstractWe conducted a large multi-ethnic meta-analysis of genome-wide association studies for primary open-angle glaucoma (POAG) on a total of 34,179 cases vs 349,321 controls, and identified 127 independent risk loci, almost doubling the number of known loci for POAG. The majority of loci have broadly consistent effect across European, Asian and African ancestries. We identify a link, both genome-wide and at specific loci, between POAG and Alzheimer’s disease. Gene expression data and bioinformatic functional analyses provide further support for the functional relevance of the POAG risk genes. Several drug compounds target these risk genes and may be potential candidates for developing no…

Closing the case ofAPOEin multiple sclerosis: no association with disease risk in over 29 000 subjects: Figure 1

2012

Background Single nucleotide polymorphisms (SNPs) rs429358 (e4) and rs7412 (e2), both invoking changes in the amino-acid sequence of the apolipoprotein E (APOE) gene, have previously been tested for association with multiple sclerosis (MS) risk. However, none of these studies was sufficiently powered to detect modest effect sizes at acceptable type-I error rates. As both SNPs are only imperfectly captured on commonly used microarray genotyping platforms, their evaluation in the context of genome-wide association studies has been hindered until recently. Methods We genotyped 12 740 subjects hitherto not studied for their APOE status, imputed raw genotype data from 8739 subjects from five ind…