ABSTRACT
BACKGROUND: Although risk factors for HIV infection are known, it is important for blood centres to understand local epidemiology and disease transmission patterns. Current risk factors for HIV infection in blood donors in Brazil were assessed. METHODS: A case-control study was conducted at large public blood centres located in four major cities between April 2009 and March 2011. Cases were persons whose donations were confirmed positive by enzyme immunoassays followed by Western blot confirmation. Audio computer-assisted structured interviews (ACASI) were completed by all cases and controls. Multivariable logistic regression was used to estimate adjusted odds ratios (AORs) and associated 95% confidence intervals (CIs). RESULTS: There were 341 cases, including 47 with recently acquired infection, and 791 controls. Disclosed risk factors for both females and males were sex with an HIV-positive person AOR 11.3, 95% CI (4.1, 31.7) and being an IVDU or sexual partner of an IVDU [AOR 4.65 (1.8, 11.7)]. For female blood donors, additional risk factors were having male sex partners who also are MSM [AOR 13.5 (3.1, 59.8)] and having unprotected sex with multiple sexual partners [AOR 5.19 (2.1, 12.9)]. The primary risk factor for male blood donors was MSM activity [AOR 21.6 (8.8, 52.9)]. Behaviours associated with recently acquired HIV were being a MSM or sex partner of MSM [13.82, (4.7, 40.3)] and IVDU [11.47, (3.0, 43.2)]. CONCLUSION: Risk factors in blood donors parallel those in the general population in Brazil. Identified risk factors suggest that donor compliance with selection procedures at the participating blood centres is inadequate.
Subject(s)
Blood Donors , HIV Infections/blood , HIV Infections/epidemiology , HIV-1 , Medical Audit , Adolescent , Brazil/epidemiology , Case-Control Studies , Female , HIV Infections/prevention & control , Humans , Male , Risk Factors , Risk-Taking , Unsafe SexABSTRACT
BACKGROUND AND OBJECTIVES: Higher risk of HIV infection could be associated with test seeking, which is one motivation for donating blood. Cognitive social capital is defined as the social support, trust and co-operation that guide community behaviour. Structural social capital refers to an individual's participation in institutions and organizations. The association between social capital and test seeking was assessed. MATERIALS AND METHODS: A survey of over 7500 donors in three Brazilian blood centres was conducted. Test seeking was classified into four non-overlapping categories (non-test seeker, possible, presumed and self-disclosed test seekers) using one direct and two indirect questions. Social capital was summarized into cognitive and structural categorizations. Multivariable logistic regression analysis was performed. RESULTS: Compared with non-test seekers (62% of survey respondents), cognitive social capital was higher for each category of test seeking (OR=1.1, 7.4, 7.1, P<0.05 respectively). Male gender, lower education and lower income were also significantly associated with test seeking. CONCLUSION: As test seekers appear to have strong social networks, blood banks may leverage this to convince them to seek testing at other locations.
Subject(s)
Blood Donors/psychology , Serologic Tests/psychology , Social Support , Adolescent , Adult , Aged , Brazil , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Serologic Tests/methods , Serologic Tests/statistics & numerical data , Social Class , Socioeconomic Factors , Young AdultABSTRACT
GMP-PNP, a non-hydrolyzable analog of GTP binds tightly to G-protein in the presence of Mg2+, so that the binding is stable even after exhaustive washings. This property was exploited to prepare membrane samples of rat brain where G-protein GTP-binding sites were saturated with GMP-PNP. Experiments carried out with these membranes showed that GTP, GMP-PNP, GDP-S and GMP (1 mM) inhibit the sodium-independent [3H]glutamate binding by 30-40% [F(4,40) = 5.9; p < .001], whereas only GMP-PNP activates adenylate cyclase activity [F(6,42) = 3.56; p < .01]. The inhibition of sodium-independent [3H]glutamate binding occurred in the absence of Mg2+. These findings suggest that guanine nucleotides may inhibit glutamate binding and activate adenylate cyclase through distinct mechanisms by acting on different sites.
