78 research outputs found

    From ‘sugar daddies’ to ‘sugar babies’: exploring a pathway among age-disparate sexual relationships, condom use and adolescent pregnancy in South Africa

    Get PDF
    Background: Adolescent pregnancy has been linked to adverse outcomes. Most studies proposing risk pathways for adolescent pregnancy in South Africa are qualitative, hypothesising links among age-disparate relationships, reduced condom use and higher pregnancy rates. No known South African studies have quantitatively explored pathways to adolescent pregnancy. Objectives: This study aimed to: (i) identify the factors associated with adolescent pregnancy and (ii) explore a pathway of risk by assessing whether condom use mediated the relationship between age-disparate sexual relationships and adolescent pregnancy. Methods: A cross-sectional survey of 447 sexually active girls aged 10–19 years was undertaken in six health districts of South Africa. Multivariate logistic regressions controlled for confounders. Mediation tests used bootstrapping. Results: Consistent condom use (ß = –2.148, odds ratio (OR) = 8.566, P = 0.001) and school enrolment (ß = –1.600, OR = 0.202, P = 0.001) were associated with lower pregnancy rates. Age-disparate sex (ß = 1.093, OR = 2.982, P = 0.001) and long-term school absences (ß = 1.402, OR = 4.061, P = 0.001) were associated with higher pregnancy rates. The indirect effect of age-disparate sex on adolescent pregnancy through condom use was significant, irrespective of age, age at sexual initiation, poverty and residential environment (B = 0.4466, s.d. = 0.1303, confidence interval: 0.2323–0.7428). Conclusion: This survey supports hypotheses that inability to negotiate condom use in age-disparate sexual relationships may drive adolescent pregnancy. Interventions addressing these relationships, facilitating condom use and increasing access to sexual health services among adolescents might avert unwanted pregnancies

    Structural analysis of an eIF3 subcomplex reveals conserved interactions required for a stable and proper translation pre-initiation complex assembly

    Get PDF
    Translation initiation factor eIF3 acts as the key orchestrator of the canonical initiation pathway in eukaryotes, yet its structure is greatly unexplored. We report the 2.2 Å resolution crystal structure of the complex between the yeast seven-bladed β-propeller eIF3i/TIF34 and a C-terminal α-helix of eIF3b/PRT1, which reveals universally conserved interactions. Mutating these interactions displays severe growth defects and eliminates association of eIF3i/TIF34 and strikingly also eIF3g/TIF35 with eIF3 and 40S subunits in vivo. Unexpectedly, 40S-association of the remaining eIF3 subcomplex and eIF5 is likewise destabilized resulting in formation of aberrant pre-initiation complexes (PICs) containing eIF2 and eIF1, which critically compromises scanning arrest on mRNA at its AUG start codon suggesting that the contacts between mRNA and ribosomal decoding site are impaired. Remarkably, overexpression of eIF3g/TIF35 suppresses the leaky scanning and growth defects most probably by preventing these aberrant PICs to form. Leaky scanning is also partially suppressed by eIF1, one of the key regulators of AUG recognition, and its mutant sui1G107R but the mechanism differs. We conclude that the C-terminus of eIF3b/PRT1 orchestrates co-operative recruitment of eIF3i/TIF34 and eIF3g/TIF35 to the 40S subunit for a stable and proper assembly of 48S pre-initiation complexes necessary for stringent AUG recognition on mRNAs

    Inherited variation in immune genes and pathways and glioblastoma risk

    Get PDF
    To determine whether inherited variations in immune function single-nucleotide polymorphisms (SNPs), genes or pathways affect glioblastoma risk, we analyzed data from recent genome-wide association studies in conjunction with predefined immune function genes and pathways. Gene and pathway analyses were conducted on two independent data sets using 6629 SNPs in 911 genes on 17 immune pathways from 525 glioblastoma cases and 602 controls from the University of California, San Francisco (UCSF) and a subset of 6029 SNPs in 893 genes from 531 cases and 1782 controls from MD Anderson (MDA). To further assess consistency of SNP-level associations, we also compared data from the UK (266 cases and 2482 controls) and the Mayo Clinic (114 cases and 111 controls). Although three correlated epidermal growth factor receptor (EGFR) SNPs were consistently associated with glioblastoma in all four data sets (Mantel–Haenzel P values = 1 × 10−5 to 4 × 10−3), independent replication is required as genome-wide significance was not attained. In gene-level analyses, eight immune function genes were significantly (minP < 0.05) associated with glioblastoma; the IL-2RA (CD25) cytokine gene had the smallest minP values in both UCSF (minP = 0.01) and MDA (minP = 0.001) data sets. The IL-2RA receptor is found on the surface of regulatory T cells potentially contributing to immunosuppression characteristic of the glioblastoma microenvironment. In pathway correlation analyses, cytokine signaling and adhesion–extravasation–migration pathways showed similar associations with glioblastoma risk in both MDA and UCSF data sets. Our findings represent the first systematic description of immune genes and pathways that characterize glioblastoma risk

    Daily intake of antioxidants in relation to survival among adult patients diagnosed with malignant glioma

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Malignant glioma is a rare cancer with poor survival. The influence of diet and antioxidant intake on glioma survival is not well understood. The current study examines the association between antioxidant intake and survival after glioma diagnosis.</p> <p>Methods</p> <p>Adult patients diagnosed with malignant glioma during 1991-1994 and 1997-2001 were enrolled in a population-based study. Diagnosis was confirmed by review of pathology specimens. A modified food-frequency questionnaire interview was completed by each glioma patient or a designated proxy. Intake of each food item was converted to grams consumed/day. From this nutrient database, 16 antioxidants, calcium, a total antioxidant index and 3 macronutrients were available for survival analysis. Cox regression estimated mortality hazard ratios associated with each nutrient and the antioxidant index adjusting for potential confounders. Nutrient values were categorized into tertiles. Models were stratified by histology (Grades II, III, and IV) and conducted for all (including proxy) subjects and for a subset of self-reported subjects.</p> <p>Results</p> <p>Geometric mean values for 11 fat-soluble and 6 water-soluble individual antioxidants, antioxidant index and 3 macronutrients were virtually the same when comparing all cases (n = 748) to self-reported cases only (n = 450). For patients diagnosed with Grade II and Grade III histology, moderate (915.8-2118.3 mcg) intake of fat-soluble lycopene was associated with poorer survival when compared to low intake (0.0-914.8 mcg), for self-reported cases only. High intake of vitamin E and moderate/high intake of secoisolariciresinol among Grade III patients indicated greater survival for all cases. In Grade IV patients, moderate/high intake of cryptoxanthin and high intake of secoisolariciresinol were associated with poorer survival among all cases. Among Grade II patients, moderate intake of water-soluble folate was associated with greater survival for all cases; high intake of vitamin C and genistein and the highest level of the antioxidant index were associated with poorer survival for all cases.</p> <p>Conclusions</p> <p>The associations observed in our study suggest that the influence of some antioxidants on survival following a diagnosis of malignant glioma are inconsistent and vary by histology group. Further research in a large sample of glioma patients is needed to confirm/refute our results.</p

    Social protection:Potential for improving HIV outcomes among adolescents

    Get PDF
    Introduction Advances in biomedical technologies provide potential for adolescent HIV prevention and HIV‐positive survival. The UNAIDS 90–90–90 treatment targets provide a new roadmap for ending the HIV epidemic, principally through antiretroviral treatment, HIV testing and viral suppression among people with HIV. However, while imperative, HIV treatment and testing will not be sufficient to address the epidemic among adolescents in Southern and Eastern Africa. In particular, use of condoms and adherence to antiretroviral therapy (ART) remain haphazard, with evidence that social and structural deprivation is negatively impacting adolescents’ capacity to protect themselves and others. This paper examines the evidence for and potential of interventions addressing these structural deprivations. Discussion New evidence is emerging around social protection interventions, including cash transfers, parenting support and educational support (“cash, care and classroom”). These interventions have the potential to reduce the social and economic drivers of HIV risk, improve utilization of prevention technologies and improve adherence to ART for adolescent populations in the hyper‐endemic settings of Southern and Eastern Africa. Studies show that the integration of social and economic interventions has high acceptability and reach and that it holds powerful potential for improved HIV, health and development outcomes. Conclusions Social protection is a largely untapped means of reducing HIV‐risk behaviours and increasing uptake of and adherence to biomedical prevention and treatment technologies. There is now sufficient evidence to include social protection programming as a key strategy not only to mitigate the negative impacts of the HIV epidemic among families, but also to contribute to HIV prevention among adolescents and potentially to remove social and economic barriers to accessing treatment. We urge a further research and programming agenda: to actively combine programmes that increase availability of biomedical solutions with social protection policies that can boost their utilization.</p

    Increasing Prevalence of Gestational Diabetes and Pregnancy-Related Hypertension in Los Angeles County, California, 1991–2003

    No full text
    IntroductionGestational diabetes and pregnancy-related hypertension can lead to adverse health effects in mothers and infants. We assessed recent trends in the rates of these conditions in Los Angeles County, California.MethodsHospital discharge data were used to identify all women aged 15–54 years who resided in the county, had a singleton delivery from 1991 through 2003, and had gestational diabetes or pregnancy-related hypertension listed as a discharge diagnosis at the time of delivery. The prevalence of each condition was calculated by calendar year, race/ethnicity, and age group. Temporal trends in the rates were assessed by using negative binomial regression models, controlling for race/ethnicity and age. Separate models were run for each racial/ethnic and age group.ResultsThe age-adjusted prevalence of gestational diabetes increased more than threefold (from 14.5 cases per 1000 women in 1991 to 47.9 cases per 1000 in 2003). The age-adjusted prevalence of pregnancy-related hypertension also increased (from 40.5 cases per 1000 in 1991 to 54.4 cases per 1000 in 2003). In the multivariable regression analysis, the annual rate increase for gestational diabetes was 8.3% overall and was highest among Hispanics (9.9%). The annual rate increase for pregnancy-related hypertension was 2.8% overall and was highest among blacks (4.8%).ConclusionThe rates of gestational diabetes and pregnancy-related hypertension are increasing in Los Angeles County. Further research is needed to determine the causes of the observed increases and the growing racial/ethnic disparities in those rates
    corecore