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101.
Chopera DR Mlotshwa M Woodman Z Mlisana K de Assis Rosa D Martin DP Abdool Karim S Gray CM Williamson C;CAPRISA Study Team 《Journal of virology》2011,85(14):7070-7080
Molecular epidemiology studies have identified HLA-B 58:01 as a protective HIV allele. However, not all B 58:01-expressing persons exhibit slow HIV disease progression. We followed six HLA-B 58:01-positive, HIV subtype C-infected individuals for up to 31 months from the onset of infection and observed substantial variability in their clinical progression despite comparable total breadths of T cell responses. We therefore investigated additional immunological and virological factors that could explain their different disease trajectories. Cytotoxic T-lymphocyte (CTL) responses during acute infection predominantly targeted the TW10 and KF9 epitopes in p24(Gag) and Nef, respectively. Failure to target the TW10 epitope in one B 58:01-positive individual was associated with low CD4(+) counts and rapid disease progression. Among those targeting TW10, escape mutations arose within 2 to 15 weeks of infection. Rapid escape was associated with preexisting compensatory mutations in the transmitted viruses, which were present at a high frequency (69%) in the study population. At 1 year postinfection, B 58:01-positive individuals who targeted and developed escape mutations in the TW10 epitope (n = 5) retained significantly higher CD4(+) counts (P = 0.04), but not lower viral loads, than non-B 58:01-positive individuals (n = 17). The high population-level frequency of these compensatory mutations may be limiting the protective effect of the B 58:01 allele. 相似文献
102.
Sumiyo Okawa Evelyn Korkor Ansah Keiko Nanishi Yeetey Enuameh Akira Shibanuma Kimiyo Kikuchi Junko Yasuoka Margaret Gyapong Seth Owusu-Agyei Abraham Rexford Oduro Gloria Quansah Asare Abraham Hodgson Masamine Jimba Ghana EMBRACE Implementation Research Project Team 《PloS one》2015,10(6)
Background
Reducing neonatal mortality is a major public health priority in sub-Saharan Africa. Numerous studies have examined the determinants of neonatal mortality, but few have explored neonatal danger signs which potentially cause morbidity. This study assessed danger signs observed in neonates at birth, determined the correlations of multiple danger signs and complications between neonates and their mothers, and identified factors associated with neonatal danger signs.Methods
A cross-sectional study was conducted in three sites across Ghana between July and September in 2013. Using two-stage random sampling, we recruited 1,500 pairs of neonates and their mothers who had given birth within the preceding two years. We collected data on their socio-demographic characteristics, utilization of maternal and neonatal health services, and experiences with neonatal danger signs and maternal complications. We calculated the correlations of multiple danger signs and complications between neonates and their mothers, and performed multiple logistic regression analysis to identify factors associated with neonatal danger signs.Results
More than 25% of the neonates were born with danger signs. At-birth danger signs in neonates were correlated with maternal delivery complications (r = 0.20, p < 0.001), and neonatal complications within the first six weeks of life (r = 0.19, p < 0.001). However, only 29.1% of neonates with danger signs received postnatal care in the first two days, and 52.4% at two weeks of life. In addition to maternal complications during delivery, maternal age less than 20 years, maternal education level lower than secondary school, and fewer than four antenatal care visits significantly predicted neonatal danger signs.Conclusions
Over a quarter of neonates are born with danger signs. Maternal factors can be used to predict neonatal health condition at birth. Management of maternal health and close medical attention to high-risk neonates are crucial to reduce neonatal morbidity in Ghana. 相似文献103.
Kenneth H. Mayer Lei Wang Beryl Koblin Sharon Mannheimer Manya Magnus Carlos del Rio Susan Buchbinder Leo Wilton Vanessa Cummings Christopher C. Watson Estelle Piwowar-Manning Charlotte Gaydos Susan H. Eshleman William Clarke Ting-Yuan Liu Cherry Mao Samuel Griffith Darrell Wheeler for the HPTN Protocol Team 《PloS one》2014,9(1)
Background
American Black men who have sex with men (MSM) are disproportionately affected by HIV, but the factors associated with this concentrated epidemic are not fully understood.Methods
Black MSM were enrolled in 6 US cities to evaluate a multi-component prevention intervention, with the current analysis focusing on the correlates of being newly diagnosed with HIV compared to being HIV-uninfected or previously diagnosed with HIV.Results
HPTN 061 enrolled 1553 Black MSM whose median age was 40; 30% self-identified exclusively as gay or homosexual, 29% exclusively as bisexual, and 3% as transgender. About 1/6th (16.2%) were previously diagnosed with HIV (PD); of 1263 participants without a prior HIV diagnosis 7.6% were newly diagnosed (ND). Compared to PD, ND Black MSM were younger (p<0.001); less likely to be living with a primary partner (p<0.001); more likely to be diagnosed with syphilis (p<0.001), rectal gonorrhea (p = 0.011) or chlamydia (p = 0.020). Compared to HIV-uninfected Black MSM, ND were more likely to report unprotected receptive anal intercourse (URAI) with a male partner in the last 6 months (p<0.001); and to be diagnosed with syphilis (p<0.001), rectal gonorrhea (p = 0.004), and urethral (p = 0.025) or rectal chlamydia (p<0.001). They were less likely to report female (p = 0.002) or transgender partners (p = 0.018). Multivariate logistic regression analyses found that ND Black MSM were significantly more likely than HIV-uninfected peers to be unemployed; have STIs, and engage in URAI. Almost half the men in each group were poor, had depressive symptoms, and expressed internalized homophobia.Conclusions
ND HIV-infected Black MSM were more likely to be unemployed, have bacterial STIs and engage in URAI than other Black MSM. Culturally-tailored programs that address economic disenfranchisement, increase engagement in care, screen for STIs, in conjunction with safer sex prevention interventions, may help to decrease further transmission in this heavily affected community. 相似文献104.
Alfred T Ben-Shlomo Y Cooper R Hardy R Cooper C Deary IJ Elliott J Gunnell D Harris SE Kivimaki M Kumari M Martin RM Power C Sayer AA Starr JM Kuh D Day IN;HALCyon Study Team 《Aging cell》2011,10(3):520-532
Several age-related traits are associated with shorter telomeres, the structures that cap the end of linear chromosomes. A common polymorphism near the telomere maintenance gene TERT has been associated with several cancers, but relationships with other aging traits such as physical capability have not been reported. As part of the Healthy Ageing across the Life Course (HALCyon) collaborative research programme, men and women aged between 44 and 90 years from nine UK cohorts were genotyped for the single-nucleotide polymorphism (SNP) rs401681. We then investigated relationships between the SNP and 30 age-related phenotypes, including cognitive and physical capability, blood lipid levels and lung function, pooling within-study genotypic effects in meta-analyses. No significant associations were found between the SNP and any of the cognitive performance tests (e.g. pooled beta per T allele for word recall z-score = 0.02, 95% CI: -0.01 to 0.04, P-value = 0.12, n = 18,737), physical performance tests (e.g. pooled beta for grip strength = -0.02, 95% CI: -0.045 to 0.006, P-value = 0.14, n = 11,711), blood pressure, lung function or blood test measures. Similarly, no differences in observations were found when considering follow-up measures of cognitive or physical performance after adjusting for its measure at an earlier assessment. The lack of associations between SNP rs401681 and a wide range of age-related phenotypes investigated in this large multicohort study suggests that while this SNP may be associated with cancer, it is not an important contributor to other markers of aging. 相似文献
105.
Randhawa AK Shey MS Keyser A Peixoto B Wells RD de Kock M Lerumo L Hughes J Hussey G Hawkridge A Kaplan G Hanekom WA Hawn TR;South African Tuberculosis Vaccine Initiative Team 《PLoS pathogens》2011,7(8):e1002174
The development of effective immunoprophylaxis against tuberculosis (TB) remains a global priority, but is hampered by a partially protective Bacillus Calmette-Guérin (BCG) vaccine and an incomplete understanding of the mechanisms of immunity to Mycobacterium tuberculosis. Although host genetic factors may be a primary reason for BCG''s variable and inadequate efficacy, this possibility has not been intensively examined. We hypothesized that Toll-like receptor (TLR) variation is associated with altered in vivo immune responses to BCG. We examined whether functionally defined TLR pathway polymorphisms were associated with T cell cytokine responses in whole blood stimulated ex vivo with BCG 10 weeks after newborn BCG vaccination of South African infants. In the primary analysis, polymorphism TLR6_C745T (P249S) was associated with increased BCG-induced IFN-γ in both discovery (n = 240) and validation (n = 240) cohorts. In secondary analyses of the combined cohort, TLR1_T1805G (I602S) and TLR6_G1083C (synonymous) were associated with increased IFN-γ, TLR6_G1083C and TLR6_C745T were associated with increased IL-2, and TLR1_A1188T was associated with increased IFN-γ and IL-2. For each of these polymorphisms, the hypo-responsive allele, as defined by innate immunity signaling assays, was associated with increased production of TH1-type T cell cytokines (IFN-γ or IL-2). After stimulation with TLR1/6 lipopeptide ligands, PBMCs from TLR1/6-deficient individuals (stratified by TLR1_T1805G and TLR6_C745T hyporesponsive genotypes) secreted lower amounts of IL-6 and IL-10 compared to those with responsive TLR1/6 genotypes. In contrast, no IL-12p70 was secreted by PBMCs or monocytes. These data support a mechanism where TLR1/6 polymorphisms modulate TH1 T-cell polarization through genetic regulation of monocyte IL-10 secretion in the absence of IL-12. These studies provide evidence that functionally defined innate immune gene variants are associated with the development of adaptive immune responses after in vivo vaccination against a bacterial pathogen in humans. These findings could potentially guide novel adjuvant vaccine strategies as well as have implications for IFN-γ-based diagnostic testing for TB. 相似文献
106.
Mujugira A Baeten JM Donnell D Ndase P Mugo NR Barnes L Campbell JD Wangisi J Tappero JW Bukusi E Cohen CR Katabira E Ronald A Tumwesigye E Were E Fife KH Kiarie J Farquhar C John-Stewart G Kidoguchi L Panteleeff D Krows M Shah H Revall J Morrison S Ondrejcek L Ingram C Coombs RW Lingappa JR Celum C;Partners PrEP Study Team 《PloS one》2011,6(10):e25828
Introduction
Stable heterosexual HIV-1 serodiscordant couples in Africa have high HIV-1 transmission rates and are a critical population for evaluation of new HIV-1 prevention strategies. The Partners PrEP Study is a randomized, double-blind, placebo-controlled trial of tenofovir and emtricitabine-tenofovir pre-exposure prophylaxis to decrease HIV-1 acquisition within heterosexual HIV-1 serodiscordant couples. We describe the trial design and characteristics of the study cohort.Methods
HIV-1 serodiscordant couples, in which the HIV-1 infected partner did not meet national guidelines for initiation of antiretroviral therapy, were enrolled at 9 research sites in Kenya and Uganda. The HIV-1 susceptible partner was randomized to daily oral tenofovir, emtricitabine-tenofovir, or matching placebo with monthly follow-up for 24–36 months.Results
From July 2008 to November 2010, 7920 HIV-1 serodiscordant couples were screened and 4758 enrolled. For 62% (2966/4758) of enrolled couples, the HIV-1 susceptible partner was male. Median age was 33 years for HIV-1 susceptible and HIV-1 infected partners [IQR (28–40) and (26–39) respectively]. Most couples (98%) were married, with a median duration of partnership of 7.0 years (IQR 3.0–14.0) and recent knowledge of their serodiscordant status [median 0.4 years (IQR 0.1–2.0)]. During the month prior to enrollment, couples reported a median of 4 sex acts (IQR 2–8); 27% reported unprotected sex and 14% of male and 1% of female HIV-1 susceptible partners reported sex with outside partners. Among HIV-1 infected partners, the median plasma HIV-1 level was 3.94 log10 copies/mL (IQR 3.31–4.53) and median CD4 count was 496 cells/µL (IQR 375–662); the majority (64%) had WHO stage 1 HIV-1 disease.Conclusions
Couples at high risk of HIV-1 transmission were rapidly recruited into the Partners PrEP Study, the largest efficacy trial of oral PrEP. (ClinicalTrials.gov ) NCT00557245相似文献107.
Sacchi CT Fukasawa LO Gonçalves MG Salgado MM Shutt KA Carvalhanas TR Ribeiro AF Kemp B Gorla MC Albernaz RK Marques EG Cruciano A Waldman EA Brandileone MC Harrison LH;São Paulo RT-PCR Surveillance Project Team 《PloS one》2011,6(6):e20675
Real-time (RT)-PCR increases diagnostic yield for bacterial meningitis and is ideal for incorporation into routine surveillance in a developing country. We validated a multiplex RT-PCR assay for Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae in Brazil. Risk factors for being culture-negative, RT-PCR positive were determined. The sensitivity of RT-PCR in cerebrospinal fluid (CSF) was 100% (95% confidence limits, 96.0%-100%) for N. meningitidis, 97.8% (85.5%-99.9%) for S. pneumoniae, and 66.7% (9.4%-99.2%) for H. influenzae. Specificity ranged from 98.9% to 100%. Addition of RT-PCR to routine microbiologic methods increased the yield for detection of S. pneumoniae, N. meningitidis, and H. influenzae cases by 52%, 85%, and 20%, respectively. The main risk factor for being culture negative and RT-PCR positive was presence of antibiotic in CSF (odds ratio 12.2, 95% CI 5.9-25.0). RT-PCR using CSF was highly sensitive and specific and substantially added to measures of meningitis disease burden when incorporated into routine public health surveillance in Brazil. 相似文献
108.
Womack JA Goulet JL Gibert C Brandt C Chang CC Gulanski B Fraenkel L Mattocks K Rimland D Rodriguez-Barradas MC Tate J Yin MT Justice AC;Veterans Aging Cohort Study Project Team 《PloS one》2011,6(2):e17217
Background
HIV infection has been associated with an increased risk of fragility fracture. We explored whether or not this increased risk persisted in HIV infected and uninfected men when controlling for traditional fragility fracture risk factors.Methodology/Principal Findings
Cox regression models were used to assess the association of HIV infection with the risk for incident hip, vertebral, or upper arm fracture in male Veterans enrolled in the Veterans Aging Cohort Study Virtual Cohort (VACS-VC). We calculated adjusted hazard ratios comparing HIV status and controlling for demographics and other established risk factors. The sample consisted of 119,318 men, 33% of whom were HIV infected (34% aged 50 years or older at baseline, and 55% black or Hispanic). Median body mass index (BMI) was lower in HIV infected compared with uninfected men (25 vs. 28 kg/m2; p<0.0001). Unadjusted risk for fracture was higher among HIV infected compared with uninfected men [HR: 1.32 (95% CI: 1.20, 1.47)]. After adjusting for demographics, comorbid disease, smoking and alcohol abuse, HIV infection remained associated with an increased fracture risk [HR: 1.24 (95% CI: 1.11, 1.39)]. However, adjusting for BMI attenuated this association [HR: 1.10 (95% CI: 0.97, 1.25)]. The only HIV-specific factor associated with fragility fracture was current protease inhibitor use [HR: 1.41 (95% CI: 1.16, 1.70)].Conclusions/Significance
HIV infection is associated with fragility fracture risk. This risk is attenuated by BMI. 相似文献109.
Medina Lara A Kigozi J Amurwon J Muchabaiwa L Nyanzi Wakaholi B Mujica Mota RE Walker AS Kasirye R Ssali F Reid A Grosskurth H Babiker AG Kityo C Katabira E Munderi P Mugyenyi P Hakim J Darbyshire J Gibb DM Gilks CF;DART Trial Team 《PloS one》2012,7(4):e33672