2,913 research outputs found

    Condom Use Self-Efficacy Score and Risky Sexual Behavior among High School Students in Southern Ethiopia

    Get PDF
    There is emerging evidence of a rise in new human immunodeficiency virus (HIV) infections in Ethiopia. This may partly be explained by an increase in risky sexual behaviors among high school adolescents. The current study was conducted to explore the association between a set of predictor variables (comprehensive HIV knowledge and condom use self-efficacy score) and an outcome variable of risky sexual behavior among high school adolescents in the Angacha District of Southern Ethiopia. The study employed a quantitative cross-sectional design to answer the research question. Primary data were collected using a self-administered questionnaire from 374 participants using a stratified random sampling technique. Descriptive statistics and bivariate and multivariate logistic regressions were computed using SPSS Version 25. The prevalence of risky sexual behavior among school adolescents was 30.04/per 1000. The Cronbach’s Alpha for condom use self-efficacy score (CUSES) was 0.79. The association between HIV comprehensive knowledge and risky sexual behavior was not statistically significant. A statistically significant association was found between CUSES and the risky sexual behavior of the student, P = 0.048, OR =2.23, 95% CI [1.007, 4.925] when the covariates were held constant. The mean CUSES for males (M = 3.44) was significantly higher than females (M = 3.22), U = 14523.5, P = 0.025, η2 = 0.016). Policy decisions to revitalize school-based adolescent sexual health promotion to empower adolescents with life skills are needed to sustain the gains of HIV/AIDS control and enhance social change in the country

    HIV+ caregivers and HIV+ non-caregivers: differences in sociodemographics, immune functioning, and quality-of-life

    Get PDF
    OBJECTIVE: To examine a cohort of HIV+ study participants, who are caregivers (CGs) and non-caregivers (NCGs), to determine whether differences exist across their sociodemographic backgrounds, immune functioning, and quality-of-life (i.e., symptom distress, physical, and mental quality-of-life). METHODS: A secondary analysis of the cross-sectional subset of the population-based Collaborations HIV Outcomes Research US Cohort (CHORUS). Sample consists of 5521 HIV+ adults; median age 43 years (SD 8.7); 88.6% male; 70.7% non-Hispanic White, 17.6% African-American, and 7.8% Hispanic. Measures include the HIV Symptom Distress Scale and the SF-12. Analytical models included t-tests and multivariate linear regression. RESULTS: HIV+ CGs have lower educational attainment than HIV+ NCGs (p=0.02). Seropositive CGs also experience greater HIV symptom distress (adjusted p<0.006) and poorer physical quality-of-life (adjusted p<0.001) than their seropostive NCG counterparts. CONCLUSION: HIV+ CGs may require different supportive services than HIV+ NCGs, suggesting a need to develop tailored interventions to address modifiable factors, such as lower education and poor physical health. Both of these factors have been associated with suboptimal antiretroviral adherence, suggesting a role for the routine screening of adherence predictors amongst HIV+ CGs. These findings may have more relevance in resource-poor settings where the prevalence of HIV is higher, with a likely growing population of informal and family CGs infected with HIV

    Влияние механической активации гидрида титана на его взаимодействие с азотом и кислородом

    Get PDF
    Показано, что размол гидрида титана в планетарной мельнице приводит к повышению удельной поверхности порошка, росту микроискажений кристаллической решетки, уменьшению содержания в нем водорода и повышению химической активности, что позволяет получать нитрид титана из него в среде азота уже при температуре 500 °С. За счет кислорода, адсорбирован ного механически активированным порошком при нагревании в атмосфере азота, происходят реакции окисления атомов титана, в результате чего образуется низший оксид Tі2О.Показано, що подрібнення гідриду титану в планетарному млині приводить до підвищення питомої поверхні порошку, зростанню дефектів кристалічної ґратки, зменшенню вмісту в ній водню і підвищенню хімічної активності. Це дає змогу досягти повного перетворення механічно активованого гідриду в нітрид титану вже за температури 500 °С і витримці упродовж однієї години в середовищі азоту. За рахунок кисню, адсорбованого механічно активованим порошком при нагрівання в атмосфері азоту, проходять реакції окиснення, в результаті чого утворюється нижчий оксид Ti2O.Milling of titanium hydride in planetary mill is shoun to increase the speci surface area of powder, to decrease the hydrogen content in it and to intensity chemical activity. This makesit possible to obtain titanium nitride from the titanium hydride in a nitrogen atmosphere at as low temperature as 500 °C . Thanks to the presence of oxygen adsorbed by mechanically activated powder under heating in a nitrogen atmosphere? Reaction of intramolecular oxidation -reduction, of titanium takes place, which results in forming the lower oxide Ti2O

    Recommendations for change in infection prevention programs and practice

    Get PDF
    Fifty years of evolution in infection prevention and control programs have involved significant accomplishments related to clinical practices, methodologies, and technology. However, regulatory mandates, and resource and research limitations, coupled with emerging infection threats such as the COVID-19 pandemic, present considerable challenges for infection preventionists. This article provides guidance and recommendations in 14 key areas. These interventions should be considered for implementation by United States health care facilities in the near future

    Structure of a putative NTP pyrophosphohydrolase: YP_001813558.1 from Exiguobacterium sibiricum 255-15.

    Get PDF
    The crystal structure of a putative NTPase, YP_001813558.1 from Exiguobacterium sibiricum 255-15 (PF09934, DUF2166) was determined to 1.78 Å resolution. YP_001813558.1 and its homologs (dimeric dUTPases, MazG proteins and HisE-encoded phosphoribosyl ATP pyrophosphohydrolases) form a superfamily of all-α-helical NTP pyrophosphatases. In dimeric dUTPase-like proteins, a central four-helix bundle forms the active site. However, in YP_001813558.1, an unexpected intertwined swapping of two of the helices that compose the conserved helix bundle results in a `linked dimer' that has not previously been observed for this family. Interestingly, despite this novel mode of dimerization, the metal-binding site for divalent cations, such as magnesium, that are essential for NTPase activity is still conserved. Furthermore, the active-site residues that are involved in sugar binding of the NTPs are also conserved when compared with other α-helical NTPases, but those that recognize the nucleotide bases are not conserved, suggesting a different substrate specificity

    Specificity of T cells in synovial fluid: high frequencies of CD8(+) T cells that are specific for certain viral epitopes

    Get PDF
    INTRODUCTION: Epstein-Barr virus (EBV) is transmitted orally, replicates in the oropharynx and establishes life-long latency in human B lymphocytes. T-cell responses to latent and lytic/replicative cycle proteins are readily detectable in peripheral blood from healthy EBV-seropositive individuals. EBV has also been detected within synovial tissue, and T-cell responses to EBV lytic proteins have been reported in synovial fluid from a patient with rheumatoid arthritis (RA). This raises the question regarding whether T cells specific for certain viruses might be present at high frequencies within synovial fluid and whether such T cells might be activated or able to secrete cytokines. If so, they might play a 'bystander' role in the pathogenesis of inflammatory joint disease. OBJECTIVES: To quantify and characterize T cells that are specific for epitopes from EBV, cytomegalovirus (CMV) and influenza in peripheral blood and synovial fluid from patients with arthritis. METHODS: Peripheral blood mononuclear cells (PBMCs) and synovial fluid mononuclear cells (SFMCs) were obtained from patients with inflammatory arthritis (including those with RA, osteoarthritis, psoriatic arthritis and reactive arthritis). Samples from human leucocyte antigen (HLA)-A2-positive donors were stained with fluorescent-labelled tetramers of HLA-A2 complexed with the GLCTLVAML peptide epitope from the EBV lytic cycle protein BMLF1, the GILGFVFTL peptide epitope from the influenza A matrix protein, or the NLVPMVATV epitope from the CMV pp65 protein. Samples from HLA-B8-positive donors were stained with fluorescent-labelled tetramers of HLA-B8 complexed with the RAKFKQLL peptide epitope from the EBV lytic protein BZLF1 or the FLRGRAYGL peptide epitope from the EBV latent protein EBNA3A. All samples were costained with an antibody specific for CD8. CD4(+) T cells were not analyzed. Selected samples were costained with antibodies specific for cell-surface glycoproteins, in order to determine the phenotype of the T cells within the joint and the periphery. Functional assays to detect release of IFN-γ or tumour necrosis factor (TNF)-α were also performed on some samples. RESULTS: The first group of 15 patients included 10 patients with RA, one patient with reactive arthritis, one patient with psoriatic arthritis and three patients with osteoarthritis. Of these, 11 were HLA-A2 positive and five were HLA-B8 positive. We used HLA-peptide tetrameric complexes to analyze the frequency of EBV-specific T cells in PBMCs and SFMCs (Figs 1 and 2). Clear enrichment of CD8(+) T cells specific for epitopes from the EBV lytic cycle proteins was seen within synovial fluid from almost all donors studied, including patients with psoriatic arthritis and osteoarthritis and those with RA. In donor RhA6, 9.5% of CD8(+ ) SFMCs were specific for the HLA-A2 restricted GLCTLVAML epitope, compared with 0.5% of CD8(+) PBMCs. Likewise in a donor with osteoarthritis (NR4), 15.5% of CD8(+) SFMCs were specific for the HLA-B8-restricted RAKFKQLL epitope, compared with 0.4% of CD8(+) PBMCs. In contrast, we did not find enrichment of T cells specific for the HLA-B8-restricted FLRGRAYGL epitope (from the latent protein EBNA3A) within SFMCs compared with PBMCs in any donors. In selected individuals we performed ELISpot assays to detect IFN-γ secreted by SFMCs and PBMCs after a short incubation in vitro with peptide epitopes from EBV lytic proteins. These assays confirmed enrichment of T cells specific for epitopes from EBV lytic proteins within synovial fluid and showed that subpopulations of these cells were able to secrete proinflammatory cytokines after short-term stimulation. We used a HLA-A2/GILGFVFTL tetramer to stain PBMCs and SFMCs from six HLA-A2-positive patients. The proportion of T cells specific for this influenza epitope was low (<0.2%) in all donors studied, and we did not find any enrichment within SFMCs. We had access to SFMCs only from a second group of four HLA-A2-positive patients with RA. A tetramer of HLA-A2 complexed to the NLVPMVATV epitope from the CMV pp65 protein reacted with subpopulations of CD8(+) SFMCs in all four donors, with frequencies of 0.2, 0.5, 2.3 and 13.9%. SFMCs from all four donors secreted TNF after short-term incubation with COS cells transfected with HLA-A2 and pp65 complementary DNA. We analyzed the phenotype of virus-specific cells within PBMCs and SFMCs in three donors. The SFMC virus-specific T cells were more highly activated than those in PBMCs, as evidenced by expression of high levels of CD69 and HLA-DR. A greater proportion of SFMCs were CD38(+), CD62L low, CD45RO bright, CD45RA dim, CD57(+) and CD28(-) when compared with PBMCs. DISCUSSION: This work shows that T cells specific for certain epitopes from viral proteins are present at very high frequencies (up to 15.5% of CD8(+) T cells) within SFMCs taken from patients with inflammatory joint disease. This enrichment does not reflect a generalized enrichment for the 'memory pool' of T cells; we did not find enrichment of T cells specific for the GILGFVFTL epitope from influenza A or for the FLRGRAYGL epitope from the EBV latent protein EBNA3A, whereas we found clear enrichment of T cells specific for the GLCTLVAML epitope from the EBV lytic protein BMLF1 and for the RAKFKQLL epitope from the EBV lytic protein BZLF1. The enrichment might reflect preferential recruitment of subpopulations of virus-specific T cells, perhaps based on expression of selectins, chemokine receptors or integrins. Alternatively, T cells specific for certain viral epitopes may be stimulated to proliferate within the joint, by viral antigens themselves or by cross-reactive self-antigens. Finally, it is theoretically possible that subpopulations of T cells within the joint are preferentially protected from apoptotic cell death. Whatever the explanation, the virus-specific T cells are present at high frequency, are activated and are able to secrete proinflammatory cytokines. They could potentially interact with synoviocytes and contribute to the maintenance of inflammation within joints in many different forms of inflammatory arthritis

    Genome analysis of the necrotrophic fungal pathogens Sclerotinia sclerotiorum and Botrytis cinerea

    Get PDF
    Sclerotinia sclerotiorum and Botrytis cinerea are closely related necrotrophic plant pathogenic fungi notable for their wide host ranges and environmental persistence. These attributes have made these species models for understanding the complexity of necrotrophic, broad host-range pathogenicity. Despite their similarities, the two species differ in mating behaviour and the ability to produce asexual spores. We have sequenced the genomes of one strain of S. sclerotiorum and two strains of B. cinerea. The comparative analysis of these genomes relative to one another and to other sequenced fungal genomes is provided here. Their 38–39 Mb genomes include 11,860–14,270 predicted genes, which share 83% amino acid identity on average between the two species. We have mapped the S. sclerotiorum assembly to 16 chromosomes and found large-scale co-linearity with the B. cinerea genomes. Seven percent of the S. sclerotiorum genome comprises transposable elements compared t

    Enhanced Rewarding Properties of Morphine, but not Cocaine, in βarrestin-2 Knock-Out Mice

    Get PDF
    The reinforcing and psychomotor effects of morphine involve opiate stimulation of the dopaminergic system via activation of mu-opioid receptors (muOR). Both mu-opioid and dopamine receptors are members of the G-protein-coupled receptor (GPCR) family of proteins. GPCRs are known to undergo desensitization involving phosphorylation of the receptor and the subsequent binding of beta(arrestins), which prevents further receptor-G-protein coupling. Mice lacking beta(arrestin)-2 (beta(arr2)) display enhanced sensitivity to morphine in tests of pain perception attributable to impaired desensitization of muOR. However, whether abrogating muOR desensitization affects the reinforcing and psychomotor properties of morphine has remained unexplored. In the present study, we examined this question by assessing the effects of morphine and cocaine on locomotor activity, behavioral sensitization, conditioned place preference, and striatal dopamine release in beta(arr2) knock-out (beta(arr2)-KO) mice and their wild-type (WT) controls. Cocaine treatment resulted in very similar neurochemical and behavioral responses between the genotypes. However, in the beta(arr2)-KO mice, morphine induced more pronounced increases in striatal extracellular dopamine than in WT mice. Moreover, the rewarding properties of morphine in the conditioned place preference test were greater in the beta(arr2)-KO mice when compared with the WT mice. Thus, beta(arr2) appears to play a more important role in the dopaminergic effects mediated by morphine than those induced by cocaine
    corecore