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1.
Kidney Int Rep ; 4(2): 245-256, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30775621

RESUMEN

INTRODUCTION: Patients with hepatitis C virus (HCV) infection and chronic kidney disease (CKD) are a high-priority population for treatment. METHODS: We performed a post hoc pooled efficacy and safety analysis that included HCV genotype 1-infected patients with compensated liver disease and CKD stages 1 to 3 who received the all-oral 3-direct-acting antiviral regimen of ombitasvir, paritaprevir, ritonavir, and dasabuvir ± ribavirin (OBV/PTV/r + DSV ± RBV) in 11 phase 3 clinical trials. Sustained virologic response rates at posttreatment week 12 (SVR12) and treatment-related adverse events (AEs), serious AEs, and renal-associated AEs are reported. Mean changes from baseline in serum creatinine and estimated glomerular filtration rate (eGFR) were calculated to assess changes in renal function. Factors associated with improved eGFR were assessed by stepwise logistic regression analysis of data from 7 trials in which baseline urinalysis was collected. RESULTS: SVR12 rates in patients with stage 1, 2, and 3 CKD were 97% (439/453), 98% (536/547), and 97% (32/33), respectively, with OBV/PTV/r + DSV; and, 96% (1172/1221), 96% (1208/1254), and 93% (55/59), respectively, with OBV/PTV/r + DSV + RBV. Overall rates of serious AEs and renal AEs were 3% (95/3567) and 2% (56/3567), respectively. Factors associated with an eGFR increase of ≥10 ml/min per 1.73 m2 were baseline proteinuria, body mass index, nonblack race, and history of diabetes. CONCLUSION: OBV/PTV/r + DSV ± RBV achieved high SVR rates and was generally well tolerated irrespective of CKD stage.

2.
Lancet HIV ; 2(2): e42-51, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26424460

RESUMEN

BACKGROUND: WHO-recommended second-line antiretroviral therapy (ART) of a pharmacologically enhanced (boosted) protease inhibitor plus nucleoside or nucleotide reverse transcriptase inhibitors (NtRTIs) might be compromised by resistance. Results of the 96 week SECOND-LINE randomised trial showed that NtRTI-sparing ART with ritonavir-boosted lopinavir and raltegravir (raltegravir-group) provided non-inferior efficacy to ritonavir-boosted lopinavir and two or three NtRTIs (NtRTI-group) in participants with virological failure composed of a first-line regimen of a non-nucleoside reverse transcriptase inhibitor plus two NtRTIs. We report the relation of baseline virological resistance with virological failure and emergent resistance on study. METHODS: As part of the randomised open-label SECOND-LINE trial, second-line ART NtRTI selection was made by either genotype (local laboratory) or algorithm. Genotypic resistance for the entire cohort at baseline was assessed on stored samples at a central laboratory. Virological failure was defined as plasma viral load greater than 200 copies per mL. Baseline viral isolates were assigned genotypic sensitivity scores (GSSs) by use of the Stanford HIV Database version 6.3.1: a global GSS (gGSS), defined as the combined GSS for lamivudine or emtricitabine, abacavir, zidovudine, stavudine, didanosine, and tenofovir and a specific GSS (sGSS) defined as the GSS for the ART regimen initiated by a specific participant. Emergent resistance was reported on samples with a viral load greater than 500 copies per mL. We used multivariate logistic regression with backward elimination to assess predictors of virological failure and emergent resistance. FINDINGS: From April 19, 2010, to July 22, 2013, 271 patients were included in the NtRTI group and and 270 in the raltegravir group. In the NtRTI group 215 had available baseline sequence data, and 240 had viral load measurements at 96 weeks; in the raltegravir group 236 had baseline sequence data and 255 had viral load measurements at 96 weeks. Median (IQR) gGSS was 3.0 (1.3-4.3) in the NtRTI group and 3.0 (1.0-4.3) in the raltegravir group. The median sGSS in the NtRTI group was 1.0 (0.5-1.8). Multivariate analysis showed significant associations between virological failure and less than complete adherence at week 4 (odds ratio [OR] 2.18, 95%CI 1.07-4.47; p=0·03) and week 48 (2.49, 1.09-5.69; p=0.03), baseline plasma viral load greater than 100,000 copies per mL (3.43, 1.70-6.94; p=0.0006), baseline gGSS >4.25 (4.73, 1.94-11.6; p=0.0007), and being Hispanic (3.13, 1.21-8.13; p=0.02) or African (3.49, 1.68-7.28; p=0.0008) rather than Asian. We observed emergent major mutations in one (1%) of 129 participants for protease (both groups), eight (13%) of 64 for reverse transcriptase (NtRTI group) and 16 (20%) of 79 for integrase. Emergent resistance was associated with the raltegravir group (OR 2.47, 95% CI 1.02-5.99; p=0.05), baseline log10 viral load (1.83, 1.12-2.97; p=0.02), and absence of the Lys65Arg (K65R) or Lys70Glu (K70E) mutation at baseline (3.18, 1.12-9.02; p=0.03). INTERPRETATION: Poor adherence was a major determinant of virological failure in people on second-line ART. In settings with limited resources, investment in optimisation of adherence rather than implementation of drug resistance testing might be advisable. FUNDING: University of New South Wales Australia, Merck, AbbVie, and the Foundation for AIDS Research.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Farmacorresistencia Viral , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Adulto , Didesoxinucleósidos/uso terapéutico , Quimioterapia Combinada , Femenino , Infecciones por VIH/psicología , Infecciones por VIH/virología , VIH-1/genética , VIH-1/aislamiento & purificación , VIH-1/fisiología , Humanos , Lamivudine/uso terapéutico , Lopinavir/uso terapéutico , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Ritonavir/uso terapéutico , Australia del Sur , Tenofovir/uso terapéutico , Resultado del Tratamiento , Carga Viral/efectos de los fármacos , Adulto Joven
4.
PLoS One ; 10(2): e0118228, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25723472

RESUMEN

OBJECTIVE: To determine the durability over 96 weeks of safety and efficacy of lopinavir/ritonavir (LPV/r) and raltegravir (RAL) which was demonstrated to have non-inferior efficacy relative to a regimen of LPV/r with nucleoside/nucleotide reverse transcriptase inhibitors (N(t)RTIs) (Control) in primary analysis at 48 weeks. DESIGN: Open label, centrally randomised trial. SETTING: Recruitment was from 37 primary and secondary care sites from Africa, Asia, Australia, Europe and Latin America. SUBJECTS: 541 HIV-1 infected adults virologically failing first-line non-NRTI + 2N(t)RTI, with no previous exposure to protease inhibitors or integrase strand transfer inhibitors were analysed, 425 completed 96 weeks follow up on randomised therapy. INTERVENTION: Randomisation was 1:1 to Control or RAL. MAIN OUTCOME MEASURES: Differences between the proportion of participants with plasma HIV-1 RNA (VL) <200 copies/mL by intention to treat were compared with a non-inferiority margin of -12%. Differences in biochemical, haematological and metabolic changes were assessed using T-tests. RESULTS: VL <200 copies/mL at 96 weeks was: RAL 80.4%, Control 76.0% (difference: 4.4 [95%CI -2.6, 11.3]) and met non-inferiority criteria. The RAL arm had a significantly higher mean change (difference Control-RAL; 95%CI) in haemoglobin (-2.9; -5.7, -1.1), total lymphocytes (-0.2; -0.3, -0.0), total cholesterol (-0.5; -0.8, -0.3), HDL cholesterol (-0.1; -0.1, -0.0) and LDL cholesterol (-0.3; -0.5, -0.2). CONCLUSION: At 96 weeks, both RAL and Control maintained efficacy greater than 75% and continued to demonstrate similar safety profiles. These results support the use of a combination LPV/r and RAL regimen as an option following failure of 1st line NNRTI + 2N(t)RTIs. TRIAL REGISTRATION: ClinicalTrials.gov NCT00931463.


Asunto(s)
Infecciones por VIH/tratamiento farmacológico , Inhibidores de Integrasa VIH/uso terapéutico , Inhibidores de la Proteasa del VIH/uso terapéutico , Lopinavir/uso terapéutico , Raltegravir Potásico/uso terapéutico , Ritonavir/uso terapéutico , Adulto , Quimioterapia Combinada , Inhibidores de Integrasa VIH/administración & dosificación , Inhibidores de Integrasa VIH/efectos adversos , Inhibidores de la Proteasa del VIH/administración & dosificación , Inhibidores de la Proteasa del VIH/efectos adversos , VIH-1 , Humanos , Lopinavir/administración & dosificación , Lopinavir/efectos adversos , Masculino , Raltegravir Potásico/administración & dosificación , Raltegravir Potásico/efectos adversos , Ritonavir/administración & dosificación , Ritonavir/efectos adversos , Atención Secundaria de Salud
5.
Clin Infect Dis ; 60(8): 1242-51, 2015 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-25609682

RESUMEN

Thirty-four human immunodeficiency virus (HIV) specialists from 16 countries contributed to this project, whose primary aim was to provide guidance on the screening, diagnosis, and monitoring of bone disease in HIV-infected patients. Four clinically important questions in bone disease management were identified, and recommendations, based on literature review and expert opinion, were agreed upon. Risk of fragility fracture should be assessed primarily using the Fracture Risk Assessment Tool (FRAX), without dual-energy X-ray absorptiometry (DXA), in all HIV-infected men aged 40-49 years and HIV-infected premenopausal women aged ≥40 years. DXA should be performed in men aged ≥50 years, postmenopausal women, patients with a history of fragility fracture, patients receiving chronic glucocorticoid treatment, and patients at high risk of falls. In resource-limited settings, FRAX without bone mineral density can be substituted for DXA. Guidelines for antiretroviral therapy should be followed; adjustment should avoid tenofovir disoproxil fumarate or boosted protease inhibitors in at-risk patients. Dietary and lifestyle management strategies for high-risk patients should be employed and antiosteoporosis treatment initiated.


Asunto(s)
Fracturas Óseas/prevención & control , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Absorciometría de Fotón , Adulto , Anciano , Anciano de 80 o más Años , Antirretrovirales/uso terapéutico , Técnicas de Apoyo para la Decisión , Femenino , Humanos , Masculino , Persona de Mediana Edad
6.
AIDS Rev ; 17(1): 37-46, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25586481

RESUMEN

Inhibition of the cytochrome p450 3A4 enzyme system leads to increases in plasma concentrations of coadministered antiretroviral agents - a concept known as pharmacokinetic boosting. Ritonavir and cobicistat are potent inhibitors of cytochrome p450 3A4. Ritonavir was initially developed as an HIV protease inhibitor, but is currently used primarily as a pharmacokinetic boosting agent for other HIV and hepatitis C protease inhibitors. Cobicistat is a boosting agent for the integrase inhibitor elvitegravir and the protease inhibitors atazanavir and darunavir. Phase III data showed that atazanavir + cobicistat + tenofovir/emtricitabine had non-inferior efficacy and resulted in similar CD4 T-cell count increases to atazanavir + ritonavir + tenofovir/emtricitabine. The tolerability, gastrointestinal, and lipid profile of the cobicistat-containing regimen was comparable with the ritonavir-containing regimen. Primary HIV protease resistance mutations were not selected in either ritonavir or cobicistat arm virologic failures. Cobicistat-containing regimens have consistently shown higher serum creatinine increases and creatinine clearance decreases compared with ritonavir, and accurate assessment of glomerular filtration in the presence of cobicistat could only be made by using exogenous markers such as iohexol. Drugs contraindicated with cobicistat are consistent with those contraindicated with ritonavir-containing protease inhibitor regimens with respect to cytochrome p450 3A interactions. Information in this review may help clinicians assess the benefits and limitations of currently available pharmacokinetic enhancers when selecting the most appropriate treatment for their patients.


Asunto(s)
Linfocitos T CD4-Positivos/efectos de los fármacos , Carbamatos/farmacocinética , Infecciones por VIH/tratamiento farmacológico , Inhibidores de la Proteasa del VIH/farmacocinética , Ritonavir/farmacocinética , Tiazoles/farmacocinética , Cobicistat , Esquema de Medicación , Interacciones Farmacológicas , VIH-1/efectos de los fármacos , Humanos
7.
Virus Res ; 120(1-2): 191-8, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16621098

RESUMEN

BACKGROUND: Viral genotype and intersubtype recombination may influence the rate and/or timing of mother-to-child HIV-1 transmission. METHODS: We determined the HIV-1 subtype of the C2-C5 env and 5'LTR regions from milk and blood samples of 61 Tanzanian mothers who transmitted the virus through breastfeeding and their HIV-1 positive non-transmitting controls. Cases and controls were matched on infant's age at sample collection. All mothers resided in Dar es Salaam, Tanzania. RESULTS: Most infections among cases were due to recombinant viruses (41.0%), followed by HIV-1 subtype A (26.2%), subtype D (19.7%), and subtype C (13.1%). In multivariate analysis including maternal CD4+ cell counts, HIV disease stage, and proviral load in breast milk, the odds of breast milk transmission were 7.2 times higher if the mother carried an intersubtype recombinant genome in comparison to a subtype C virus (p=0.02). Viruses with recombinant LTRs were 4.9 times more likely to be transmitted through breastfeeding than viruses with non-recombinant LTRs of subtype A, C or D combined (p=0.01). CONCLUSIONS: This suggested that intersubtype recombinant genomes, and especially recombination within the LTR, might render HIV-1 more fit for transmission via breast milk in comparison with non-recombinant subtypes A, C, and D.


Asunto(s)
Lactancia Materna/epidemiología , Seropositividad para VIH/epidemiología , Seropositividad para VIH/transmisión , VIH-1/genética , Transmisión Vertical de Enfermedad Infecciosa , Epidemiología Molecular , Complicaciones Infecciosas del Embarazo/epidemiología , Adulto , Lactancia Materna/efectos adversos , Recuento de Linfocito CD4 , Progresión de la Enfermedad , Femenino , Duplicado del Terminal Largo de VIH/genética , Seropositividad para VIH/diagnóstico , Seropositividad para VIH/inmunología , VIH-1/clasificación , Humanos , Recién Nacido , Leche Humana/virología , Datos de Secuencia Molecular , Análisis Multivariante , Embarazo , Recombinación Genética , Factores de Riesgo , Especificidad de la Especie , Tanzanía/epidemiología , Carga Viral
8.
Clin Infect Dis ; 42(6): 843-52, 2006 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-16477563

RESUMEN

BACKGROUND: Many different subtypes of human immunodeficiency virus (HIV) type 1 have been identified, particularly in sub-Saharan Africa. However, much remains unknown regarding the relative pathogenicity of these subtypes and their influence on the clinical progression of HIV infection. We examined prospectively the associations between HIV-1 subtypes A, C, and D and recombinant viruses, as well as the rates of disease progression in a cohort of seropositive women from Dar es Salaam, Tanzania. METHODS: A total of 428 pregnant mothers participating in a larger controlled trial of the effect of vitamin supplements were selected for DNA sequencing of their HIV-1 subtype. Plasma viral load was measured at baseline, and CD4+ cell counts was assessed at baseline and at regular intervals throughout the follow-up period. Proportional hazards regression (hazards ratio [HR]) analysis was used to measure the association between viral subtype and the rate of disease progression. RESULTS: Relative to patients with subtype A, patients with subtype D experienced the most rapid progression to death (HR, 2.27; 95% confidence interval [CI], 1.46-3.52) or to the World Health Organization stage 4 of illness (HR, 1.94; 95% CI, 1.20-3.14) and to a CD4+ cell count of <200 cells/mm3 (HR, 2.12; 95% CI, 1.42-3.17). After adjustment for viral load, CD4+ cell count, and other baseline covariates, the associations remained similar. CONCLUSIONS: We observed heterogeneity in the rates of disease progression of HIV-1 disease in infected persons, on the basis of the infecting subtype. Subtype D was associated with the most rapid progression of the disease, relative to the other 3 categories of viruses in our cohort.


Asunto(s)
Infecciones por VIH/virología , VIH-1/clasificación , VIH-1/patogenicidad , Adulto , Recuento de Linfocito CD4 , Estudios de Cohortes , ADN Viral/análisis , Progresión de la Enfermedad , Femenino , Infecciones por VIH/mortalidad , VIH-1/genética , Humanos , Datos de Secuencia Molecular , Embarazo , Análisis de Secuencia de ADN , Tanzanía/epidemiología
9.
J Acquir Immune Defic Syndr ; 41(1): 93-9, 2006 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-16340480

RESUMEN

BACKGROUND: Transmission through breast-feeding is an important cause of infant HIV-1 infections in developing countries; however, its mechanism remains largely unknown. We have explored the association between cell-free virus (CFV) and cell-associated virus (CAV) levels in breast milk (BM), as reflected by viral RNA and proviral DNA, respectively, and the risk of infant HIV-1 infection after 6 weeks postpartum. METHODS: Sixty-one HIV-positive mothers who transmitted HIV-1 by BM were matched to 61 HIV-positive nontransmitting mothers based on their infant's age at sample collection. CFV and CAV were quantified in a single milk specimen per mother preceding the infant's first HIV-positive result. RESULTS: After adjusting for maternal CD4 cell counts and disease stage, each 10-fold increase in CFV or CAV load was associated with an almost 3-fold increase in BM transmission. Whereas CAV load was predictive of transmission before and after 9 months postpartum, CFV was a significant predictor of transmission occurring only after 9 months. Phylogenetic analyses of the C2 to C5 env region showed that 85% of infants (11 of 13 infants) harboring viruses that clustered with CFV in their mother's milk were infected after 9 months postpartum. CONCLUSION: A reduction in milk CAV and CFV loads might significantly decrease HIV-1 transmission by breast-feeding.


Asunto(s)
Lactancia Materna/efectos adversos , Seropositividad para VIH/transmisión , VIH-1/aislamiento & purificación , Leche Humana/virología , Vitaminas/uso terapéutico , Adulto , Recuento de Linfocito CD4 , Estudios de Casos y Controles , Sistema Libre de Células , Suplementos Dietéticos , Método Doble Ciego , Femenino , Productos del Gen env/genética , Seropositividad para VIH/inmunología , VIH-1/genética , Humanos , Lactante , Recién Nacido , Leche Humana/citología , Datos de Secuencia Molecular , Placebos , Análisis de Regresión , Tanzanía , Vitaminas/administración & dosificación
10.
AIDS ; 18(12): 1629-36, 2004 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-15280773

RESUMEN

OBJECTIVE: To determine whether different HIV-1 genotypes present in a single cohort, in Dar es Salaam, Tanzania, showed differences in timing for transmission from mothers to their infants. METHODS: We determined the maternal viral load, transmission time, and the HIV-1 envelope (env) subtype of 253 HIV-1-infected infants enrolled in a randomized double-blind placebo-controlled trial to examine the efficacy of vitamins in decreasing mother-to-child transmission in Tanzania. Classification of HIV-1 positivity in utero was based on PCR results at birth. Infants were classified as intrapartum infected if they scored negative for the sample collected at birth and positive for the sample collected at 6 weeks of age. RESULTS: We found significant differences in the distribution of transmission time according to subtype. A higher proportion of HIV-1 with subtype C env (C-env) was transmitted in utero than HIV-1 with subtype A env (A-env), subtype D env (D-env), or both combined. CONCLUSIONS: The identification of patterns of mother-to-child transmission times among HIV-1 genotypes may be useful in the selection of drug regimens for chemoprophylaxis. Based on our results, the efficacy of regimens administered only at labor may not protect as large a fraction of infants born in geographical regions with subtype C-env epidemics as compared to epidemics in regions where subtypes A-env and D-env predominate in the population.


Asunto(s)
Infecciones por VIH/transmisión , VIH-1/genética , Transmisión Vertical de Enfermedad Infecciosa , Adolescente , Adulto , Lactancia Materna , Método Doble Ciego , Femenino , Genes env/genética , Genotipo , Infecciones por VIH/sangre , Humanos , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Embarazo , Factores de Riesgo , Factores de Tiempo , Carga Viral , Vitaminas/administración & dosificación
11.
Virology ; 307(2): 278-82, 2003 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-12667797

RESUMEN

Samples from infants infected in-utero by the human immunodeficiency virus type 1 (HIV-1) subtypes A, C, D, and recombinants from Dar es Salaam, Tanzania, were examined for the presence of viral genetic quasispecies. HIV-1 envelope diversity was measured on peripheral blood mononuclear cells collected within the first 48 h of life from 53 infants. Phylogenetic analysis of C2-C5 envelope nucleotide sequences was used for HIV-1 subtype classification. Forty-two of 53 samples (79%) showed a heteroduplex mobility assay (HMA) suggestive of transmission of a single quasispecies, while 21% showed infection with multiple quasispecies. No differences among HIV-1 subtypes were found in the proportion of single to multiple quasispecies transmitted in-utero (Likelihood ratio test, P = 0.83), nor were differences found among single to multiple quasispecies transmitted and maternal viral load (Mann-Whitney test, P = 0.44). This suggests that differences in perinatal transmission between subtypes we previously observed in this cohort could not be associated with the likelihood for multiple independent infections during in-utero infections.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/transmisión , VIH-1/genética , Transmisión Vertical de Enfermedad Infecciosa , Recuento de Linfocito CD4 , Femenino , Genotipo , Humanos , Lactante , Embarazo
12.
Sex Transm Dis ; 30(3): 187-92, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12616132

RESUMEN

BACKGROUND: Type-specific serological tests have allowed for a better understanding of the epidemiology of herpes simplex virus type 2 (HSV-2) infection in Africa. GOAL: The goal was to determine risk factors for HSV-2 among bar and hotel workers in Moshi, Tanzania. STUDY DESIGN: A cross-sectional study was conducted involving 515 workers in randomly selected bars and hotels in Moshi. RESULTS: The seroprevalence of HSV-2 was 43.5%. Women were more likely to be HSV-2-seropositive than men (age-adjusted OR = 3.8; 95% CI = 2.5-5.8). In multivariate analyses, age was positively associated with HSV-2 in both women and men. HIV-1-seropositive women had a significantly increased risk of HSV-2 infection (adjusted OR = 2.8; 95% CI = 1.5-5.1). Other predictors of HSV-2 were religion and sexual behavior for women and level of education, frequency of alcohol use, and concurrent partners for men. CONCLUSION: The most common genital infection was that with HSV-2. Control of HSV-2 might be an important strategy for HIV-1 infection prevention in this population.


Asunto(s)
Herpes Genital/epidemiología , Herpesvirus Humano 1/aislamiento & purificación , Herpesvirus Humano 2/aislamiento & purificación , Lugar de Trabajo , Adolescente , Adulto , Factores de Edad , Alcoholismo , Estudios Transversales , Femenino , Herpes Genital/etiología , Humanos , Modelos Logísticos , Masculino , Prevalencia , Factores de Riesgo , Asunción de Riesgos , Factores Sexuales , Enfermedades de Transmisión Sexual/epidemiología , Enfermedades de Transmisión Sexual/etiología , Tanzanía/epidemiología
13.
AIDS Res Hum Retroviruses ; 19(1): 57-64, 2003 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-12596722

RESUMEN

The HIV-1 prevalence among bar and hotel workers in Tanzania suggests they are a high-risk group for HIV-1 infection. We determined the HIV-1 subtype of 3'-p24/5'-p7 gag and C2-C5 env sequences from 40 individuals representing this population in Moshi. Genetic patterns composed of A(gag)-A(env), C(gag)-C(env), and D(gag)-D(env) were found in 19 (48.0%), 8 (20.0%), and 3 (8.0%) samples, respectively. The remaining 10 samples (25%) had different subtypes in gag and env, indicative of intersubtype recombinants. Among these recombinants, two contained sequences from HIV-1 subsubtype A2, a new genetic variant in Tanzania. Five bar and hotel workers may have been infected with viruses from a common source, based on phylogenetic analysis. The information obtained by surveillance of HIV-1 subtypes in a high-risk population should be useful in the design and evaluation of behavioral, therapeutic, and vaccine trial interventions aimed at reducing HIV-1 transmission.


Asunto(s)
Infecciones por VIH/virología , VIH-1/clasificación , Actividades Recreativas , Enfermedades Profesionales/virología , Restaurantes , Genes env , Genes gag , Proteína gp120 de Envoltorio del VIH/genética , Infecciones por VIH/epidemiología , VIH-1/genética , Humanos , Datos de Secuencia Molecular , Fragmentos de Péptidos/genética , Filogenia , Recombinación Genética , Análisis de Secuencia de ADN , Tanzanía/epidemiología , Viaje
14.
AIDS Res Hum Retroviruses ; 19(12): 1115-23, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14709248

RESUMEN

Hypermutation involving excessive G-to-A substitutions in the dinucleotide context GA or GG is common among the lentiviruses and results in multiple stop codons across the genome. Hypermutated viruses have been associated with slower disease progression and might reflect an antiviral cell-defense mechanism. However, it is unclear how soon G-to-A substitutions are generated after infection and whether they occur randomly along the genome. In this report we describe for the first time hypermutated sequences detected at delivery and in the first weeks of life, which suggests that they could be either generated in utero and soon after birth and/or vertically transmitted. Hypermutated C2-C5 env clones were harbored in 13.2% of 243 infants and 18.6% of 199 mothers. A lower extent of hypermutation was found in infants than in mothers (Fisher's exact p = 0.034), but there was no relationship between the percent hypermutated Gs and viral subtype or transmission status of the mother. Analyses of six hypermutated full-length HIV-1 clones showed that although all genes could be affected by G-to-A substitutions, there was a significant drop in the extent of hypermutation between the central polypurine tract and the beginning of env, indicating that hypermutation across the HIV-1 genome might occur in a specific pattern. The genomic regions most affected by hypermutation were pol and env while both polypurine tracts remained unaffected. A better understanding of the mechanism of hypermutation may reveal novel virus-host interactions that could be targeted in drug development.


Asunto(s)
Genoma Viral , Infecciones por VIH/virología , VIH-1/genética , Transmisión Vertical de Enfermedad Infecciosa , Mutación , Femenino , Productos del Gen env/química , Variación Genética , VIH-1/aislamiento & purificación , VIH-1/fisiología , Humanos , Lactante , Recién Nacido , Datos de Secuencia Molecular , Ensayos Clínicos Controlados Aleatorios como Asunto , Análisis de Secuencia de ADN
15.
J Acquir Immune Defic Syndr ; 31(3): 331-8, 2002 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-12439210

RESUMEN

BACKGROUND: Transmission of HIV-1 through breastfeeding is a major problem, although its timing is not well characterized. METHODS: The authors examined the timing and correlates of HIV-1 transmission through breastfeeding among 1078 HIV-infected pregnant women from Dar es Salaam, Tanzania enrolled in a trial to examine the effect of vitamin A and other vitamin supplements on mother-to-child transmission of HIV-1 and other health outcomes. Cumulative incidence was measured among children of women not randomized to vitamin A (n = 312), given the higher risk of infection observed among those in the vitamin A arm. For analyses of correlates, data from all children not infected by age 6 weeks were used (p = 659). RESULTS: Mean duration of breastfeeding was 20.3 months (SD = 4.4 months; median = 20.5 months). Thirty-seven infections were observed during 4372 child-months of follow-up evaluation, or 10.2 cases per 100 child-years. Infection risk by age 4 months was 3.8% (95% confidence interval [CI], 1.6%-6.1%) and increased to 17.9% (95% CI, 11.2%-24.5%) by age 24 months. In a multivariate proportional hazards model, high maternal viral load (p =.0001), low CD4 cell count (p =.004), and high maternal erythrocyte sedimentation rate (ESR; p=.004) were significant predictors of transmission of HIV-1 through breastfeeding. Mothers who had breast lesions during pregnancy were 2.00 times more likely to transmit the virus during breastfeeding than mothers without these lesions (95% CI, 1.29-3.08; p=.002). CONCLUSIONS: The rate of breastfeeding transmission of HIV-1 is high, and early weaning is likely to be associated with reduced transmission. Antiretroviral drugs given to HIV-infected mothers are likely to reduce the risk of breastfeeding transmission. In their absence, interventions that enhance immune reconstitution, such as micronutrient supplements, may be beneficial against transmission. Methods to prevent and treat nipple cracks and mastitis may also be important.


Asunto(s)
Lactancia Materna/efectos adversos , Infecciones por VIH/transmisión , VIH-1 , Transmisión Vertical de Enfermedad Infecciosa , Preescolar , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Humanos , Lactante , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Embarazo , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Factores de Riesgo , Tanzanía , Vitaminas/administración & dosificación
16.
AIDS Res Hum Retroviruses ; 18(13): 947-56, 2002 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-12230937

RESUMEN

Human immunodeficiency virus type 1 (HIV-1) subtypes A, C, and D are cocirculating in Tanzania, and large numbers of recombinant genomes have been reported from this region. Here we describe full-length sequences of six unlinked HIV-1 subtype A and D recombinants. The samples came from newborns, indicating that the recombination patterns were vertically transmitted and were functionally competent. All six genomes had different recombination patterns with one to eight cross-over points frequently located at the beginning or end of functionally defined regions. In five of the six viruses most of gag, pol, tat, and rev and the intracytoplasmic domain of gp41 were classified as subtype D. In all but one genome, the external domain of gp41 and the majority of gp120 belonged to subtype A. A recombination site common to four of the six genomes was located at the transmembrane domain of gp41, at the end of the rev response element. The identification of subtype patterns among intersubtype recombinant genomes from recently infected individuals may reveal genetic determinants of improved viral fitness or advantage for transmission.


Asunto(s)
Genoma Viral , Infecciones por VIH/virología , VIH-1/clasificación , VIH-1/genética , Transmisión Vertical de Enfermedad Infecciosa , Recombinación Genética , ADN Viral/análisis , Humanos , Lactante , Recién Nacido , Datos de Secuencia Molecular , Filogenia , Análisis de Secuencia de ADN , Tanzanía
17.
AIDS ; 16(14): 1935-44, 2002 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-12351954

RESUMEN

BACKGROUND: HIV-1 transmission through breastfeeding is a global problem and has been associated with poor maternal micronutrient status. METHODS: A total of 1078 HIV-infected pregnant women from Tanzania were randomly assigned to vitamin A or multivitamins excluding A from approximately 20 weeks' gestation and throughout lactation. RESULTS: Multivitamins excluding A had no effect on the total risk of HIV-1 transmission (RR 1.04, 95% CI 0.82-1.32, P= 0.76). Vitamin A increased the risk of transmission (RR 1.38, 95% CI 1.09-1.76, P = 0.009). Multivitamins were associated with non-statistically significant reductions in transmission through breastfeeding, and mortality by 24 months among those alive and not infected at 6 weeks. Multivitamins significantly reduced breastfeeding transmission in infants of mothers with low baseline lymphocyte counts (RR 0.37; 95% CI 0.16-0.85, P = 0.02) compared with infants of mothers with higher counts (RR 0.99, 95% CI 0.68-1.45, P = 0.97; -for-interaction 0.03). Multivitamins also protected against transmission among mothers with a high erythrocyte sedimentation rate (P-for-interaction 0.06), low hemoglobin (P-for-interaction 0.06), and low birthweight babies (P-for-interaction 0.04). Multivitamins reduced death and prolonged HIV-free survival significantly among children born to women with low maternal immunological or nutritional status. Vitamin A alone increased breastfeeding transmission but had no effect on mortality by 24 months. CONCLUSION: Vitamin A increased the risk of HIV-1 transmission. Multivitamin (B, C, and E) supplementation of breastfeeding mothers reduced child mortality and HIV-1 transmission through breastfeeding among immunologically and nutritionally compromised women. The provision of these supplements to HIV-infected lactating women should be considered.


Asunto(s)
Lactancia Materna , Infecciones por VIH/transmisión , VIH-1 , Enfermedades del Recién Nacido/prevención & control , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Vitaminas/uso terapéutico , Adulto , Niño , Suplementos Dietéticos , Método Doble Ciego , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Lactante , Recién Nacido , Enfermedades del Recién Nacido/mortalidad , Transmisión Vertical de Enfermedad Infecciosa/estadística & datos numéricos , Mortalidad , Estado Nutricional , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Tanzanía/epidemiología , Vitamina A/administración & dosificación , Vitamina A/uso terapéutico , Vitaminas/administración & dosificación
18.
J Acquir Immune Defic Syndr ; 29(4): 409-17, 2002 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-11917247

RESUMEN

We conducted this study to determine the prevalence and risk factors for HIV-1 infection among women (N = 312) who were working in the bars and hotels in Moshi, a town in northern Tanzania. Study subjects were interviewed to obtain information about HIV-1 risk factors and examined to collect samples for the diagnosis of sexually transmitted diseases (STDs). The prevalence of HIV-1 was 26.3% (95% confidence interval [CI], 21.4%-31.2%). In multivariate analyses, the risk of HIV-1 increased with increasing age (p value, test for linear trend <.001) and the number of sexual partners during the last 5 years (p value, test for linear trend <.03). Other significant predictors were having a male partner with other sexual partners (Adjusted odds ratio [AOR], 1.92; 95% CI, 1.03-3.60), and consuming alcohol >2 days per week (AOR, 2.56; 95% CI, 1.12-5.88). The risk of HIV-1 was also significantly increased in women with bacterial vaginosis (AOR, 2.37; 95% CI, 1.09-5.13) and in study subjects with herpes simplex virus (HSV)-2 antibodies (AOR, 2.48; 95% CI, 1.24-4.98). These results indicate that women working in these settings were at increased risk of HIV-1. Programs aiming at promoting safer sexual practices and control of other STDs are urgently needed in this population. Such programs should address the underlying conditions that facilitate risk behaviors and create obstacles for these women who wish to protect themselves against HIV-1.


Asunto(s)
Brotes de Enfermedades , Infecciones por VIH/epidemiología , VIH-1 , Trabajo Sexual , Adolescente , Adulto , Femenino , Humanos , Actividades Recreativas , Masculino , Prevalencia , Factores de Riesgo , Enfermedades de Transmisión Sexual/epidemiología , Tanzanía/epidemiología , Viaje
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