21 research outputs found
School wellbeing among children in grades 1 - 10
<p>Abstract</p> <p>Background</p> <p>Determinants of children's school wellbeing have not been extensively studied. In this cross-sectional study of school children we assessed how factors assumed to promote wellbeing and factors assumed to adversely influence wellbeing were associated with self-reported wellbeing in school.</p> <p>Methods</p> <p>Children from five schools, 230 boys and 189 girls in grades 1-10, responded to the same set of questions. We used proportional odds logistic regression to assess the associations of promoting and restraining factors with school wellbeing.</p> <p>Results</p> <p>In a multivariable analysis, degree of school wellbeing in boys was strongly and positively related to enjoying school work (odds ratio, 3.84, 95% CI 2.38 to 6.22) and receiving necessary help (odds ratio, 3.55, 95% CI 2.17 to 5.80) from teachers. In girls, being bothered during lessons was strongly and negatively associated with school wellbeing (odds ratio, 0.43, 95% CI 0.22 to 0.85).</p> <p>Conclusions</p> <p>Different factors may determine school wellbeing in boys and girls, but for both genders, factors relevant for lessons may be more important than factors related to recess. Especially in boys, the student-teacher relationship may be of particular importance.</p
Identification of a novel proinsulin-associated SNP and demonstration that proinsulin is unlikely to be a causal factor in subclinical vascular remodelling using Mendelian randomisation
Background and aims
Increased proinsulin relative to insulin levels have been associated with subclinical atherosclerosis (measured by carotid intima-media thickness (cIMT)) and are predictive of future cardiovascular disease (CVD), independently of established risk factors. The mechanisms linking proinsulin to atherosclerosis and CVD are unclear. A genome-wide meta-analysis has identified nine loci associated with circulating proinsulin levels. Using proinsulin-associated SNPs, we set out to use a Mendelian randomisation approach to test the hypothesis that proinsulin plays a causal role in subclinical vascular remodelling.
Methods
We studied the high CVD-risk IMPROVE cohort (n = 3345), which has detailed biochemical phenotyping and repeated, state-of-the-art, high-resolution carotid ultrasound examinations. Genotyping was performed using Illumina Cardio-Metabo and Immuno arrays, which include reported proinsulin-associated loci. Participants with type 2 diabetes (n = 904) were omitted from the analysis. Linear regression was used to identify proinsulin-associated genetic variants.
Results
We identified a proinsulin locus on chromosome 15 (rs8029765) and replicated it in data from 20,003 additional individuals. An 11-SNP score, including the previously identified and the chromosome 15 proinsulin-associated loci, was significantly and negatively associated with baseline IMTmean and IMTmax (the primary cIMT phenotypes) but not with progression measures. However, MR-Eggers refuted any significant effect of the proinsulin-associated 11-SNP score, and a non-pleiotropic SNP score of three variants (including rs8029765) demonstrated no effect on baseline or progression cIMT measures.
Conclusions
We identified a novel proinsulin-associated locus and demonstrated that whilst proinsulin levels are associated with cIMT measures, proinsulin per se is unlikely to have a causative effect on cIMT
Meta-GWAS of PCSK9 levels detects two novel loci at <em>APOB</em> and <em>TM6SF2</em>.
BACKGROUND: Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a key player in lipid metabolism, as it degrades LDL receptors from hepatic cell membranes. So far, only variants of the PCSK9 gene locus were found to be associated with PCSK9 levels. Here we aimed to identify novel genetic loci that regulate PCSK9 levels and how they relate to other lipid traits. Additionally, we investigated to what extend the causal effect of PCSK9 on coronary artery disease (CAD) is mediated by LDL-C. METHODS & RESULTS: We performed a genome-wide association study meta-analysis of PCSK9 levels in up to 12,721 samples of European ancestry. The estimated heritability was 10.3%, which increased to 12.6% using only samples from patients without statin treatment. We successfully replicated the known PCSK9 hit consisting of three independent signals. Interestingly, in a study of 300 African Americans, we confirmed the locus with a different PCSK9 variant. Beyond PCSK9, our meta-analysis detected three novel loci with genome-wide significance. Co-localization analysis with cis-eQTLs and lipid traits revealed biologically plausible candidate genes at two of them: APOB and TM6SF2. In a bivariate Mendelian Randomization analysis, we detected a strong effect of PCSK9 on LDL-C, but not vice versa. LDL-C mediated 63% of the total causal effect of PCSK9 on CAD. CONCLUSION: Our study identified novel genetic loci with plausible candidate genes affecting PCSK9 levels. Ethnic heterogeneity was observed at the PCSK9 locus itself. While the causal effect of PCSK9 on CAD is mainly mediated by LDL-C, an independent direct effect also occurs
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Sex and statin-related genetic associations at the PCSK9 gene locus: results of genome-wide association meta-analysis.
BACKGROUND: Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a key player of lipid metabolism with higher plasma levels in women throughout their life. Statin treatment affects PCSK9 levels also showing evidence of sex-differential effects. It remains unclear whether these differences can be explained by genetics. METHODS: We performed genome-wide association meta-analyses (GWAS) of PCSK9 levels stratified for sex and statin treatment in six independent studies of Europeans (8936 women/11,080 men respectively 14,825 statin-free/5191 statin-treated individuals). Loci associated in one of the strata were tested for statin- and sex-interactions considering all independent signals per locus. Independent variants at the PCSK9 gene locus were then used in a stratified Mendelian Randomization analysis (cis-MR) of PCSK9 effects on low-density lipoprotein cholesterol (LDL-C) levels to detect differences of causal effects between the subgroups. RESULTS: We identified 11 loci associated with PCSK9 in at least one stratified subgroup (p < 1.0 × 10-6), including the PCSK9 gene locus and five other lipid loci: APOB, TM6SF2, FADS1/FADS2, JMJD1C, and HP/HPR. The interaction analysis revealed eight loci with sex- and/or statin-interactions. At the PCSK9 gene locus, there were four independent signals, one with a significant sex-interaction showing stronger effects in men (rs693668). Regarding statin treatment, there were two significant interactions in PCSK9 missense mutations: rs11591147 had stronger effects in statin-free individuals, and rs11583680 had stronger effects in statin-treated individuals. Besides replicating known loci, we detected two novel genome-wide significant associations: one for statin-treated individuals at 6q11.1 (within KHDRBS2) and one for males at 12q24.22 (near KSR2/NOS1), both with significant interactions. In the MR of PCSK9 on LDL-C, we observed significant causal estimates within all subgroups, but significantly stronger causal effects in statin-free subjects compared to statin-treated individuals. CONCLUSIONS: We performed the first double-stratified GWAS of PCSK9 levels and identified multiple biologically plausible loci with genetic interaction effects. Our results indicate that the observed sexual dimorphism of PCSK9 and its statin-related interactions have a genetic basis. Significant differences in the causal relationship between PCSK9 and LDL-C suggest sex-specific dosages of PCSK9 inhibitors
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Sex and statin-related genetic associations at the PCSK9 gene locus: results of genome-wide association meta-analysis
Acknowledgements: We thank Robert John Konrad and his team at Ely Lilly and Company for the PCSK9 measurements in serum samples from the TwinGene cohort. We thank Sylvia Henger for data QC of LIFE-Adult and LIFE-Heart, Kay Olischer and Annegret Unger for technical assistance regarding LIFE-Heart, and Kerstin Wirkner for running the LIFE-Adult study center. We thank all study participants of the LIFE-Adult study whose personal dedication and commitment have made this project possible. LIFE-Adult genotyping (round3) was done at the Cologne Center for Genomics (CCG, University of Cologne, Peter Nürnberg and Mohammad R. Toliat). For LIFE-Adult genotype imputation, compute infrastructure provided by ScaDS (Dresden/Leipzig Competence Center for Scalable Data Services and Solutions) at the Leipzig University Computing Centre was used. We thank the LURIC study team who were either temporarily or permanently involved in patient recruitment as well as sample and data handling, in addition to the laboratory staff at the Ludwigshafen General Hospital and the Universities of Freiburg and Ulm, Germany. We thank all participants of the GCKD and KORA studies for enabling our research through their participation. The vigorous effort of the study personnel of the regional centers of the GCKD study and the KORA study is highly appreciated.Funder: Universität Leipzig (1039)Abstract
Background
Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a key player of lipid metabolism with higher plasma levels in women throughout their life. Statin treatment affects PCSK9 levels also showing evidence of sex-differential effects. It remains unclear whether these differences can be explained by genetics.
Methods
We performed genome-wide association meta-analyses (GWAS) of PCSK9 levels stratified for sex and statin treatment in six independent studies of Europeans (8936 women/11,080 men respectively 14,825 statin-free/5191 statin-treated individuals). Loci associated in one of the strata were tested for statin- and sex-interactions considering all independent signals per locus. Independent variants at the PCSK9 gene locus were then used in a stratified Mendelian Randomization analysis (cis-MR) of PCSK9 effects on low-density lipoprotein cholesterol (LDL-C) levels to detect differences of causal effects between the subgroups.
Results
We identified 11 loci associated with PCSK9 in at least one stratified subgroup (p < 1.0 × 10–6), including the PCSK9 gene locus and five other lipid loci: APOB, TM6SF2, FADS1/FADS2, JMJD1C, and HP/HPR. The interaction analysis revealed eight loci with sex- and/or statin-interactions. At the PCSK9 gene locus, there were four independent signals, one with a significant sex-interaction showing stronger effects in men (rs693668). Regarding statin treatment, there were two significant interactions in PCSK9 missense mutations: rs11591147 had stronger effects in statin-free individuals, and rs11583680 had stronger effects in statin-treated individuals. Besides replicating known loci, we detected two novel genome-wide significant associations: one for statin-treated individuals at 6q11.1 (within KHDRBS2) and one for males at 12q24.22 (near KSR2/NOS1), both with significant interactions. In the MR of PCSK9 on LDL-C, we observed significant causal estimates within all subgroups, but significantly stronger causal effects in statin-free subjects compared to statin-treated individuals.
Conclusions
We performed the first double-stratified GWAS of PCSK9 levels and identified multiple biologically plausible loci with genetic interaction effects. Our results indicate that the observed sexual dimorphism of PCSK9 and its statin-related interactions have a genetic basis. Significant differences in the causal relationship between PCSK9 and LDL-C suggest sex-specific dosages of PCSK9 inhibitors.
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Identification of a novel proinsulin-associated SNP and demonstration that proinsulin is unlikely to be a causal factor in subclinical vascular remodelling using Mendelian randomisation
Background and aims: Increased proinsulin relative to insulin levels have been associated with subclinical atherosclerosis (measured by carotid intima-media thickness (cIMT)) and are predictive of future cardiovascular disease (CVD), independently of established risk factors. The mechanisms linking proinsulin to atherosclerosis and CVD are unclear. A genome-wide meta-analysis has identified nine loci associated with circulating proinsulin levels. Using proinsulin-associated SNPs, we set out to use a Mendelian randomisation approach to test the hypothesis that proinsulin plays a causal role in subclinical vascular remodelling. Methods: We studied the high CVD-risk IMPROVE cohort (n = 3345), which has detailed biochemical phenotyping and repeated, state-of-the-art, high-resolution carotid ultrasound examinations. Genotyping was performed using Illumina Cardio-Metabo and Immuno arrays, which include reported proinsulin-associated loci. Participants with type 2 diabetes (n = 904) were omitted from the analysis. Linear regression was used to identify proinsulin-associated genetic variants. Results: We identified a proinsulin locus on chromosome 15 (rs8029765) and replicated it in data from 20,003 additional individuals. An 11-SNP score, including the previously identified and the chromosome 15 proinsulin-associated loci, was significantly and negatively associated with baseline IMTmean and IMTmax (the primary cIMT phenotypes) but not with progression measures. However, MR-Eggers refuted any significant effect of the proinsulin-associated 11-SNP score, and a non-pleiotropic SNP score of three variants (including rs8029765) demonstrated no effect on baseline or progression cIMT measures. Conclusions: We identified a novel proinsulin-associated locus and demonstrated that whilst proinsulin levels are associated with cIMT measures, proinsulin per se is unlikely to have a causative effect on cIMT. (C) 2017 The Authors. Published by Elsevier Ireland Ltd.Peer reviewe
Taking Toll: The Impact of Sexual and Gender Harassment in the Lives of Middle and High School Students
Middle school and high school are difficult spaces traversed by adolescents. Caught up in the midst of one of the most challenging developmental stages of life, adolescents are simultaneously trying to individuate from others (parents and peers), while trying to fit in with peers and the larger social context. There are many adults who fondly reminisce about their high school days, recalling that time as happy and hope-filled. But, for many young people, those days are anything but care-free. Many students experience sexual and/or gender harassment during their middle and high school years
Perilipin 5 is protective in the ischemic heart
Background: Myocardial ischemia is associated with alterations in cardiac metabolism, resulting in decreased fatty acid oxidation and increased lipid accumulation. Here we investigate how myocardial lipid content and dynamics affect the function of the ischemic heart, and focus on the role of the lipid droplet protein perilipin 5 (Plin5) in the pathophysiology of myocardial ischemia. Methods and results: We generated Plin5(-/-) mice and found that Plin5 deficiency dramatically reduced the triglyceride content in the heart. Under normal conditions, Plin5(-/-) mice maintained a close to normal heart function by decreasing fatty acid uptake and increasing glucose uptake, thus preserving the energy balance. However, during stress or myocardial ischemia, Plin5 deficiency resulted in myocardial reduced substrate availability, severely reduced heart function and increased mortality. Importantly, analysis of a human cohort with suspected coronary artery disease showed that a common noncoding polymorphism, rs884164, decreases the cardiac expression of PLIN5 and is associated with reduced heart function following myocardial ischemia, indicating a role for Plin5 in cardiac dysfunction. Conclusion: Our findings indicate that Plin5 deficiency alters cardiac lipid metabolism and associates with reduced survival following myocardial ischemia, suggesting that Plin5 plays a beneficial role in the heart following ischemia. (C) 2016 The Authors. Published by Elsevier Ireland Ltd