Publications by authors named "Clyde E Hart"

Background: While prior epidemiologic studies have suggested that injectable progestin-based contraceptive depot medroxyprogesterone acetate (DMPA) use may increase a woman's risk of acquiring HIV, recent data have suggested that DMPA users may be at a similar risk for HIV acquisition as users of the copper intrauterine device and levonorgestrel implant. Use of the etonogestrel Implant (Eng-Implant) is increasing but there are currently no studies evaluating its effect on HIV acquisition risk.

Objective: Evaluate the potential effect of the Eng-Implant use on HIV acquisition risk by analyzing HIV target cells and cytokine profiles in the lower genital tract and blood of adult premenopausal HIV-negative women using the Eng-Implant.

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Introduction: Oral pre-exposure prophylaxis (PrEP) with tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) is highly effective in preventing HIV infection among men who have sex with men (MSM). The effects of consistent personal lubricant use in the rectum on tissue PrEP drug concentrations and the rectal microbiota are unknown. We investigated rectal PrEP drug concentrations and the microbiota in MSM before and after repeated rectal application of a hyperosmolar lubricant.

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The female genital tract (FGT) provides a means of entry to pathogens, including HIV, yet immune cell populations at this barrier between host and environment are not well defined. We initiated a study of healthy women to characterize resident T cell populations in the lower FGT from lavage and patient-matched peripheral blood to investigate potential mechanisms of HIV sexual transmission. Surprisingly, we observed FGT CD4 T cell populations were primarily CCR7(hi), consistent with a central memory or recirculating memory T cell phenotype.

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The potent nonnucleoside reverse transcriptase inhibitor UC781 has been safety tested as a vaginal microbicide gel formulation for prevention of HIV-1 sexual transmission. To investigate whether UC781 retained anti-infective activity following exposure to the female genital tract, we conducted an ex vivo analysis of the UC781 levels and antiviral activity in cervicovaginal lavage (CVL) fluids from 25 Thai women enrolled in a 14-day safety trial of twice-daily vaginal application of two concentrations of the UC781 microbicide gel. CVL samples were collected from women in the 0.

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This study compared HIV-1 genotypes shed over time (≤3.5 years) in the vaginal secretions (VS) and blood plasma (BP) of 15 chronically infected women. Analysis of predicted coreceptor tropism (CCR5=R5, CXCR4=X4) for quasispecies shedding revealed three patterns: (1) viral quasispecies shed in both VS and BP were restricted to R5-tropism at all time points, (2) quasispecies shed in VS were restricted to R5-tropism at all time points but X4 quasispecies were identified in the BP at one or more time points, and (3) quasispecies shed in matched VS and BP both contained X4-tropic viruses.

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The predominant mode of HIV-1 infection is heterosexual transmission, where a genetic bottleneck is imposed on the virus quasispecies. To probe whether limited genetic diversity in the genital tract (GT) of the transmitting partner drives this bottleneck, viral envelope sequences from the blood and genital fluids of eight transmission pairs from Rwanda and Zambia were analyzed. The chronically infected transmitting partner's virus population was heterogeneous with distinct genital subpopulations, and the virus populations within the GT of two of four women sampled longitudinally exhibited evidence of stability over time intervals on the order of weeks to months.

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Background: Among human immunodeficiency virus (HIV)-infected men who have sex with men (MSM) taking combination antiretroviral therapy (cART), the impact of rectal sexually transmitted infections (STIs) on rectal HIV-1 shedding is unknown.

Methods: Human immunodeficiency virus type 1 (HIV-1) RNA was quantified from rectal swabs collected for Neisseria gonorrhoeae (GC) and Chlamydia trachomatis (CT) screening of HIV-1-infected MSM. Correlations of STIs with rectal viral load were explored using multinomial regression modeling.

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Quality medical laboratory services are an integral part of routine health care, medical research, and public health systems. Despite this vital role, quality laboratory services in Africa are scarce. The crucial need for expanding quality laboratory services throughout sub-Saharan Africa is especially critical because of the region's burden of disease.

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Objective: To examine the persistence of compartmentalized HIV drug resistance mutations (DRM) over time in the female genital tract and its effect on pol gene divergence compared to that in blood.

Design: Longitudinal cohort of 22 antiretroviral-experienced women in the Emory Vaginal Ecology study.

Methods: Blood and vaginal secretions were collected at serial clinic visits.

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Objective: To assess the safety of the candidate microbicide Carraguard gel in HIV-positive women and men.

Design: A randomized, placebo-controlled, triple-blinded clinical trial of Carraguard gel when applied vaginally once per day for 14 intermenstrual days by sexually abstinent and sexually active HIV-positive women; and when applied directly to the penis once per day for 7 days by sexually abstinent HIV-positive men.

Methods: In each cohort (n = 20 per cohort), participants were randomized to Carraguard, methylcellulose placebo, or no product (1:1:1).

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Recent studies indicate that mucosal innate immune factors modulate HIV-1 infection in vitro. Our interest was to examine the levels of innate mucosal factors for their potential association with HIV-1 shedding in the female genital tract. Vaginal lavages were collected from HIV-1-infected women who had vaginal viral loads (VVL) that were below, within, or above the 90% confidence interval (CI) predicted by their matched plasma viral loads.

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Most human immunodeficiency virus type 1 (HIV-1) infections are believed to be the result of exposure to the virus in genital secretions. However, prevention and therapeutic strategies are usually based on characterizations of HIV-1 in blood. To understand better the dynamics between HIV-1 quasispecies in the genital tract and blood, we performed heteroduplex assays on amplified env products from cell-free viral RNA in paired vaginal secretion (VS) and blood plasma (BP) samples of 14 women followed for 1.

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A standardized protocol was used to compare cellular toxicities and anti-human immunodeficiency virus type 1 (HIV-1) activities of candidate microbicides formulated for human use. The microbicides evaluated were cellulose acetate phthalate (CAP), Carraguard, K-Y plus nonoxynol-9 (KY-N9), PRO 2000 (0.5 and 4%), SPL7013 (5%), UC781 (0.

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Infectious human immunodeficiency virus type 1 (HIV-1) is difficult to detect in female genital secretions by standard virus culture techniques. To improve detection of cell-free HIV-1 in female genital secretions, we adapted a short-term assay that uses the multinuclear-activation galactosidase indicator (MAGI) assay. When vaginal lavages from HIV-1-infected women were tested with the adapted MAGI assay, 25 (64%) of 39 lavages with detectable, cell-free HIV-1 RNA were shown to have infectious virus.

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To determine whether the menstrual cycle affects human immunodeficiency virus (HIV) type 1 levels in vaginal secretions, vaginal lavage samples were collected at 7, 14, and 21 days after initiation of menses, to compare virus levels during the follicular, ovulatory, and luteal phases. During 33 menstrual cycles in 25 women, HIV-1 RNA levels in vaginal secretions ranged from <1000 to 5.3x10(7) copies per lavage, and weekly changes ranged from <0.

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