Project description:<p>The overall aim of this study is to investigate the role of impulsivity as an endophenotype for drug addiction. Although impulsivity is considered one of the strongest candidate endophenotypes for addiction, progress in the field is hampered by the heterogeneity of impulsivity, characterized by multiple personality, psychiatric, and neurocognitive dimensions, rarely examined concurrently in the same population; and the heterogeneity of addiction phenotypes, due in part to the high rates of polysubstance dependence among substance users. To address these challenges, we have developed a program of addiction research in Bulgaria, a key transit country for heroin trafficking due to its strategic geographical location on the "Balkan Drug Route" and a major European center for production of synthetic amphetamine-type stimulants. This has allowed us to access rare populations of predominantly mono-substance dependent heroin and amphetamine users, many in protracted abstinence. Our preliminary results reveal a complex relationship between trait and neurocognitive (state) dimensions of impulsivity, often manifested in opposite directions in heroin and amphetamine dependent individuals. Pilot computational modeling analyses of decision-making, a central neurocognitive aspect of impulsivity, have proved particularly informative by indicating that different mechanisms may underlie the impaired decision-making of opiate and stimulant users. A different modeling approach, i.e. phenotypic modeling, holds significant promise to address the pervasive "missing heritability" problem in genetic studies. While genetic heterogeneity is often invoked as an explanation, the manner in which complex phenotypic traits are measured and modeled is equally important contributor to the missing heritability problem but has received much less attention in the literature. Despite the multidimensionality of traits measured by psychometric, diagnostic, and neurocognitive instruments, most GWAS studies typically use aggregate sum scores that do not reflect the underlying phenotypic multidimensionality. Therefore, at least part of the missing heritability problem may originate in misspecification of the phenotypic models. Consequently, sample sizes requirements may increase from ~800 subjects in correctly specified models to 6,000-16,000 subjects in incorrectly specified models. The current study aims to increase our understanding of the complex relationship between multiple putative impulsivity endophenotypes to help redefine endophenotypes as multi-level combination of measures that could inform multivariate multilevel models of complex phenotypes. The specific aims of the study are to: (1) Assess the utility of various personality, psychiatric, and neurocognitive indices of impulsivity (either individually or in combination) as candidate endophenotype(s) for drug addiction in general and for opiate and stimulant addictions in particular; (2) Evaluate the viability of computational model parameters modeling various neurocognitive dimensions of impulsivity as novel endophenotype(s) for addiction; and (3) Test the external validity of the optimal endophenotype(s) by evaluating their associations with HIV and other risk behaviors in opiate and stimulant users in protracted abstinence, a question of critical importance for prevention and intervention efforts in this much less-well understood stage of the addiction cycle. </p>
Project description:Modification of Gene Expression of Skeletal Muscle in Response to postmenopause with or without Hormone Replacement Therapy. Test samples randomly selected from a larger study in order to verify the validity of microarray experiment. Keywords: time course analysis from HRT users and non-users
Project description:Exposure to electronic cigarette (e-cigarette) aerosol has been linked to a number of health concerns, including DNA damage, elevated oxidative stress, release of inflammatory cytokine, and dysfunctions in epithelial barriers. However, little is known about the effect of exclusive e-cigarette use on expression profiles of exosomal miRNAs, which play critical regulatory roles in many inflammatory responses and disease process including cancer. We aim to compare the exosomal microRNAs expression profile between exclusive e-cigarette users and normal controls without any tobacco product use (non-users). Using blood and urine samples from exclusive e-cigarette users and non-users in the Population Assessment of Tobacco and Health (PATH) Wave 1 study (2013-2014), we examined exosomal microRNAs expression levels through Illumina NextSeq 500/550 sequencing. We identified microRNAs that have significantly higher expression levels in exclusive e-cigarette users than non-users. Gene enrichment analysis of these significant exosomal microRNAs showed their involvement in cancer related pathways, which might indicate a potential elevated risk of cancer among exclusive e-cigarette users.
Project description:Modification of Gene Expression of Skeletal Muscle in Response to postmenopause with or without Hormone Replacement Therapy. Even though menopause is often accompanied with first signs of age-associated changes in muscle structure and function, the effects of hormone replacement therapy (HRT) or menopause-related decline in estrogen production in the muscles of postmenopausal women is not well understood. We have used a randomized double-blinded study design together with an explorative microarray experiment to characterize possible effects of continuous, combined HRT and estrogen deprivation on the skeletal muscle of fifteen early postmenopausal women from which 10 used HRT and 5 used placebo for 12-months in a douple-blinded design. Keywords: time course analysis from HRT users and non-users
Project description:Modification of Gene Expression of Skeletal Muscle in Response to postmenopause with or without Hormone Replacement Therapy. Even though menopause is often accompanied with first signs of age-associated changes in muscle structure and function, the effects of hormone replacement therapy (HRT) or menopause-related decline in estrogen production in the muscles of postmenopausal women is not well understood. We have used a randomized double-blinded study design together with an explorative microarray experiment to characterize possible effects of continuous, combined HRT and estrogen deprivation on the skeletal muscle of fifteen early postmenopausal women from which 10 used HRT and 5 used placebo for 12-months in a douple-blinded design. Keywords: time course analysis from HRT users and non-users comparison of gene expression in skeletal muscle of healthy postmenopausel women using HRT (n=10) vs not-using HRT (n=5)
Project description:HIV and Methamphetamine study - Translational Methamphetamine AIDS Research Center - Dopamine-regulated inflammatory biomarkers A digital transcript panel was custom-made based on Hs_NeuroPath_v1 (Nanostring) to accommodate dopamine-regulated inflammatory genes that were previously identified in vitro, and hypothesized to cluster HIV+ Methamphetamine users.
Project description:Methcathinone (ephedrone) is relatively easily accessible for abuse. Its users develop an extrapyramidal syndrome and it is not known if this is caused by methcathinone itself, by side-ingredients (manganese), or both. In the present study we aimed to clarify molecular mechanisms underlying this condition. We used microarrays to analyze whole genome gene expression patterns of peripheral blood from 20 methcathinone users and 20 matched controls. Gene expression profile data were analyzed by Bayesian modelling and functional annotation. Of 28,869 genes on the microarrays, 326 showed statistically significant differential expression with FDR adjusted p-values below 0.05. Quantitative RT-PCR confirmed differential expression for the most of the genes selected for validation. Functional annotation and network analysis indicated activation of a gene network that included immunological disease, cellular movement and cardiovascular disease functions (enrichment score 42). As HIV and HCV infections were confounding factors, we performed additional stratification of patients. A similar functional activation of the “immunological disease” category was evident when we compared patients according to injection status (past versus current users, balanced for HIV and HCV infection). However, this difference was not large therefore the major effect was related to the HIV status of the patients. Mn-methcathinone abusers have blood RNA expression patterns that mostly reflect their HIV and HCV infections. However, despite the strong confounding effect from infection, some modest drug abuse effects on gene expression were detected. 40 samples, 20 healthy volunteers and 20 illicit methcathinone users