Factors associated with inconsistent condom use in adolescents with negative or unknown HIV status in Northwest Cameroon

The purpose of this study is to evaluate the association between utilization of HIV testing and condom use amongst Cameroonian youths/adolescents who are not known to be HIV-infected. Worldwide, HIV is spreading most quickly amongst youths/adolescents. Between 44% and 82% of sexually active youths in Cameroon report inconsistent condom use. Data regarding utilization of HIV testing and condom use are lacking. A cross-sectional survey was administered to 431 youths ages 12-26 years in Cameroon from September 2011 to December 2011. Data on sociodemographics, sexual risk behaviors, self-reported HIV status, and condom use were collected. We compared rates of inconsistent condom use between those with known HIV negative status who utilized testing (HIV-N) and those with unknown status due to unutilized testing (HIV-U). Inconsistent condom use was defined as responding never, sometimes, or usually, while consistent condom use was defined as responding always to questions regarding frequency of condom use. Generalized estimating equations were applied to assess the association between HIV testing and inconsistent condom use, adjusting for other confounders. Of 414 eligible respondents, 205 were HIV-U and 209 were HIV-N. HIV-U subjects were younger (mean age - 16.4 vs. 17.9, p \u3c 0.001) and more likely to report living in an urban area (p - 0.002) than HIV-N subjects. Seventy-two percent (137/191) of sexually active youths reported inconsistent condom use. After adjusting for potential confounders, HIV-U status (odds ratio [OR] = 3.97, 95% confidence interval [CI] = 1.68-6.01) was associated with inconsistent condom use. Similarly, female gender (OR = 3.2, 95% CI = 1.29-7.89) was associated with inconsistent condom use, while older age at sexual debut was associated with a decreased risk for inconsistent condom use (OR = 0.67, 95% CI = 0.56-0.81). Cameroonian adolescents report high rates of inconsistent condom use which we found to be associated with self-reported unknown HIV status due to unutilized HIV testing. Successful HIV prevention programs among African youths/adolescents may benefit from expanded HIV testing programs

Socioeconomic position, lifestyle habits and biomarkers of epigenetic aging: A multi-cohort analysis

Differences in health status by socioeconomic position (SEP) tend to be more evident at older ages, suggesting the involvement of a biological mechanism responsive to the accumulation of deleterious exposures across the lifespan. DNA methylation (DNAm) has been proposed as a biomarker of biological aging that conserves memory of endogenous and exogenous stress during life. We examined the association of education level, as an indicator of SEP, and lifestyle-related variables with four biomarkers of age-dependent DNAm dysregulation: the total number of stochastic epigenetic mutations (SEMs) and three epigenetic clocks (Horvath, Hannum and Levine), in 18 cohorts spanning 12 countries. The four biological aging biomarkers were associated with education and different sets of risk factors independently, and the magnitude of the effects differed depending on the biomarker and the predictor. On average, the effect of low education on epigenetic aging was comparable with those of other lifestyle-related risk factors (obesity, alcohol intake), with the exception of smoking, which had a significantly stronger effect. Our study shows that low education is an independent predictor of accelerated biological (epigenetic) aging and that epigenetic clocks appear to be good candidates for disentangling the biological pathways underlying social inequalities in healthy aging and longevity

Socioeconomic position, lifestyle habits and biomarkers of epigenetic aging: A multi-cohort analysis

Differences in health status by socioeconomic position (SEP) tend to be more evident at older ages, suggesting the involvement of a biological mechanism responsive to the accumulation of deleterious exposures across the lifespan. DNA methylation (DNAm) has been proposed as a biomarker of biological aging that conserves memory of endogenous and exogenous stress during life.We examined the association of education level, as an indicator of SEP, and lifestyle-related variables with four biomarkers of age-dependent DNAm dysregulation: the total number of stochastic epigenetic mutations (SEMs) and three epigenetic clocks (Horvath, Hannum and Levine), in 18 cohorts spanning 12 countries.The four biological aging biomarkers were associated with education and different sets of risk factors independently, and the magnitude of the effects differed depending on the biomarker and the predictor. On average, the effect of low education on epigenetic aging was comparable with those of other lifestyle-related risk factors (obesity, alcohol intake), with the exception of smoking, which had a significantly stronger effect.Our study shows that low education is an independent predictor of accelerated biological (epigenetic) aging and that epigenetic clocks appear to be good candidates for disentangling the biological pathways underlying social inequalities in healthy aging and longevity

Socioeconomic position, lifestyle habits and biomarkers of epigenetic aging: A multi-cohort analysis

Differences in health status by socioeconomic position (SEP) tend to be more evident at older ages, suggesting the involvement of a biological mechanism responsive to the accumulation of deleterious exposures across the lifespan. DNA methylation (DNAm) has been proposed as a biomarker of biological aging that conserves memory of endogenous and exogenous stress during life. We examined the association of education level, as an indicator of SEP, and lifestyle-related variables with four biomarkers of age-dependent DNAm dysregulation: the total number of stochastic epigenetic mutations (SEMs) and three epigenetic clocks (Horvath, Hannum and Levine), in 18 cohorts spanning 12 countries. The four biological aging biomarkers were associated with education and different sets of risk factors independently, and the magnitude of the effects differed depending on the biomarker and the predictor. On average, the effect of low education on epigenetic aging was comparable with those of other lifestyle-related risk factors (obesity, alcohol intake), with the exception of smoking, which had a significantly stronger effect. Our study shows that low education is an independent predictor of accelerated biological (epigenetic) aging and that epigenetic clocks appear to be good candidates for disentangling the biological pathways underlying social inequalities in healthy aging and longevity

CD45 alternative exon expression in murine and human CD4+ T cell subsets

Leukocytes express a family of high m.w. glycoproteins called leukocyte common Ag (CD45), which are involved in phosphotyrosine signal transduction. Antibodies to different CD45 isoforms distinguish functionally different CD4+ T cell subsets in humans, rats, and mice. Selected protein isoforms are expressed through a process of exon splicing that is cell-type and differentiation-state specific. Splicing of the three variable exons, A, B, and C, which encode amino acids located near the extracellular amino terminus of the protein, potentially results in generation of eight different mRNA transcripts. The purpose of the present study was to determine the relative levels of all eight different CD45 transcripts present in a panel of murine CD4+ T cell lines and normal murine and human CD4+ T cell subsets separated with antibodies to CD45 variable exons. We show, as expected, that the broad features of CD45 surface isoform expression in these cells can be accounted for by the relative amounts of the eight differentially spliced transcripts. Unexpectedly, all the differences in CD45 isoform expression among the CD4+ T cell subpopulations that we measured could be accounted for by differences in the overall level of variable exon expression. We did not see differences among T cell populations in the relative expression of particular variable exons. Exon B was always found in greater abundance than exons C or A. Of the dual exon species, only AB and BC were found in CD4+ T cells. The AC species was undetectable. Human CD4+ T cells, especially those in the naive subset, express higher levels of CD45 variable exons than murine CD4+ T cells