Browsing by Author "Whitworth, James"

Now showing 1 - 4 of 4
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    Molecular Epidemiology of HIV Type 1 in a Rural Community in Southwest Uganda
    (AIDS Research and Human Retroviruses, 2000) Kaleebu, Pontiano; Whitworth, James; Hamilton, Laura; Rutebemberwa, Alleluiah; Lyagoba, Fred; Morgan, Dilys; Duffield, Melanie; Biryahwaho, Benon; Magambo, Brian; Oram, Jon
    The molecular epidemiology of a population-based cohort in a cluster of 15 villages in southwestern Uganda was investigated by sequencing part of the p24 gag gene and performing heteroduplex mobility assays (HMAs) of the V3 region of the env gene. Sequence and HM A data, obtained for 69 and 88 proviruses, respectively, showed that the clade A and D viruses were present at a ratio of about 0.67:1. No other clades were detected. Thirteen (22%) of 59 proviruses for which both gag and env data were obtained appeared to be recombinants. Although both clade A and D viruses were present in 13 of the villages, their distribution was unequal: for example, from env data 59% of clade A viruses were found in the eastern villages, compared with only 27% of clade D viruses. Phylogenetic (maximum likelihood) analysis of the p24 gag sequences showed a total of five clusters supported by bootstrap resampling values above or close to 75%. Four clusters were sexual partners, but there was no known sexual contact between the persons in the other cluster. The DNA sequences showed between 0.5 and 8.3% divergence from the cohort clade A or D consensus sequences. The sequences were not closely related to those published for other clade A or D proviruses.
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    Money, men and markets: Economic and sexual empowerment of market women in southwestern Uganda
    (An International Journal for Research, Intervention and Care, 2005) Nyanzi, Barbara; Nyanzi, Stella; Wolff, Brent; Whitworth, James
    Market trading requires access to cash, independent decision-making, mobility and social interaction. This study sought to explore whether market work empowers women with respect to spending decisions and negotiation over sex and condom-use. A semi-structured questionnaire was administered to 212 market women; and 12 focus group discussions and 52 in-depths interviews were conducted among market women in southwestern Uganda. Market women reported high levels of independence, mobility, assertiveness and social interaction. Access to cash was not synonymous with control over it, however. Spending decisions were limited by men’s ability to selectively withdraw finances for expenditures central to women’s concerns including household and children’s needs. Trading in markets earns women masculine labels such as kiwagi, characterized variously as independent, rebellious and insubordinate. Earning money does not change expectations of correct behaviour for wives, making it difficult for women to initiate, deny sex or ask for condoms. Independence and income from market work may make it easier for women to enter and exit new sexual relationships. However, unable to protect themselves within partnerships, HIV risk may increase as a result.
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    The Relationship between HIV Type 1 Disease Progression and V3 Serotype in a Rural Ugandan Cohort
    (AIDS Research & Human Retroviruses, 2004) Senkaali, David; Muwonge, Richard; Morgan, Dilys; Yirrell, David; Whitworth, James; Kaleebu, Pontiano
    Antigenic properties of the V3 region are reflected by HIV-1 serotypes. These may represent biological properties of the virus. We serotyped HIV-1 in 142 serum samples from participants in a rural Uganda cohort who seroconverted between August 1991 and December 2001. Clinical progression was assessed using Cox proportional hazards and Kaplan–Meier methods. Of 112 (79%) samples successfully serotyped, 36% were serotype A, 17% serotype B, 18% serotype C, and 29% serotype D. Median follow-up time, age at enrollment, and first CD4 count were similar in each serotype group. Clinical progression was faster for serotype D than other serotypes to AIDS or death, death, and CD4 count <200 cells/mm3 (all p < 0.05). HIV-1 V3 serotypes are associated with variations in the pathogenicity of HIV-1 and should be taken into account when studying the biological relevance of HIV-1 diversity.
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    Relationship between HIV-1 Env subtypes A and D and disease progression in a rural Ugandan cohort
    (AIDS, 2001) Kaleebu, Pontiano; Ross, Amanda; Morgan, Dilys; Yirrell, Davida; Oram, Jonb; Rutebemberwa, Alleluiah; Lyagoba, Fred; Hamilton, Laura; Biryahwaho, Benon; Whitworth, James
    To investigate the role of HIV-1 envelope subtypes on disease progression in a rural cohort of Ugandan adults where two major HIV-1 subtypes (A and D) exist. Participants of a clinical cohort seen between December 1995 and December 1998 had blood collected for HIV-1 subtyping. These included prevalent cases (people already infected with HIV at the start of the study in 1990) and incident cases (those who seroconverted between 1990 and December 1998). HIV-1 subtyping was carried out by heteroduplex mobility assay and DNA sequencing in the V3 env region. Disease progression was measured by the rate of CD4 lymphocyte count decline, clinical progression for the incident cases as time from seroconversion to AIDS or death, to ®rst CD4 lymphocyte count , 200 3 106/l and to the World Health Organization clinical stage 3. All analyses were adjusted for age and sex. One hundred and sixty-four individuals, including 47 prevalent and 117 incident cases, had V3 env subtype data of which 65 (40%) were subtyped as A and 99 as D. In the incident cases, 44 (38%) were subtyped as A and 73 as D. There was a suggestion that for most end-points A had a slower progression than D. The cumulative probability of remaining free from AIDS or death at 6 years post-seroconversion was 0.72 [95% con®dence interval (CI), 0.50 to 0.85] for A and 0.58 (95% CI, 0.42 to 0.71) for D, and the adjusted hazard ratio of subtype D compared to A was estimated to be 1.39 (95% CI, 0.66 to 2.94; P 0.39). The estimated difference in rates of decline in square root CD4 lymphocyte counts was ÿ0.41 per year (95% CI, ÿ0.98 to 0.15; P 0.15). This study suggests that although subtype A may have a slower progression than D, HIV-1 envelope subtype is not a major factor in determining the progression of HIV-1 disease in a rural population in Uganda.