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1.
Orphanet J Rare Dis ; 19(1): 153, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38605390

RESUMEN

BACKGROUND: Fabry disease (FD) is a rare X-linked lysosomal storage disorder with a heterogeneous clinical presentation. Patients with FD may exhibit early signs/symptoms including neuropathic pain, gastrointestinal complaints, and dermatologic manifestations. FD may ultimately progress to renal, neurologic, and cardiac dysfunction. Current treatments for FD have significantly improved the management and outcomes for patients with FD, but important clinical and convenience limitations still exist. METHODS: To illuminate the impact of FD on daily life from the patient's perspective, we asked adult patients (≥ 18 years old) with FD in the United States and Canada to complete a 33-question online survey to assess patient-reported disease severity, management, and treatment outcomes. RESULTS: A total of 280 respondents with FD completed the survey; they had a mean age of 47 years, and 68% (191/280) were women. Most were currently receiving FD treatment (84%, 234/280) with enzyme replacement therapy (ERT) (89%, 208/234) or chaperone therapy (11%, 26/234). Common symptoms included low energy/fatigue (72%, 201/280), tingling (62%, 174/280) or pain in the hands/feet (60%, 168/280), ringing in ears/hearing loss (54%, 151/280), general body pains/pain crises (51%, 143/280), and abdominal/stomach pain (50%, 140/280). More than half (51%, 144/280) of respondents reported their symptoms as bothersome (38%, 106/280) or difficult to control (14%, 38/280). Temporary symptom worsening between infusions was reported by about half of respondents: 51% (108/211) currently receiving ERT and 48% (14/29) previously receiving ERT. Only 48% (59/122) of respondents reported their symptom worsening to their physician. Of those who reported it, 41% (24/59) said that their physician prescribed medication to manage their symptoms or changed their treatment regimen. CONCLUSIONS: Our analysis highlights the gap between current standard-of-care in disease monitoring and patient perception of disease progression among patients with FD. This information may be helpful for healthcare providers and drug developers seeking to improve the care of patients with FD by addressing unmet needs of high relevance.


Asunto(s)
Enfermedad de Fabry , Femenino , Humanos , Masculino , Persona de Mediana Edad , alfa-Galactosidasa/uso terapéutico , Estudios Transversales , Terapia de Reemplazo Enzimático , Enfermedad de Fabry/tratamiento farmacológico , Enfermedad de Fabry/diagnóstico , Dolor , Medición de Resultados Informados por el Paciente , Encuestas y Cuestionarios , Brote de los Síntomas , Pueblos de América del Norte , Canadá , Estados Unidos
2.
Mult Scler J Exp Transl Clin ; 8(1): 20552173211069852, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35024161

RESUMEN

BACKGROUND: Prior studies suggest comparable effectiveness of dimethyl fumarate (DMF) and fingolimod (FTY) in multiple sclerosis (MS) using relapse, Expanded Disability Status Score (EDSS), and magnetic resonance imaging (MRI) lesion metrics. OBJECTIVE: Compare the real-world effectiveness of DMF versus FTY using quantitative, validated neuroperformance tests, MRI, and serum neurofilament light chain (sNfL) outcomes while controlling for between-group differences. METHODS: Patients were eligible if on DMF or FTY when first enrolled in the MS Partners Advancing Technology and Health Solutions (MS PATHS) network and had ≥1-year follow-up in MS PATHS. Sensitivity analysis included a subgroup who started DMF/FTY ≤2 years from enrolment. After propensity score weighting, differences in means and in mean 1-year change of neuroperformance and MRI outcomes were compared. sNfL levels were assessed. This was a non-randomized comparison. RESULTS: In the overall cohort, no significant differences were observed between DMF (n = 702) and FTY (n = 600) in neuroperformance or MRI outcomes including brain volume loss; mean time (SD) since treatment initiation was 1.98 (0.68) years for DMF and 2.02 (0.75) years for FTY. A sensitivity analysis controlling for DMF and FTY treatment duration yielded similar results. CONCLUSION: In this study, DMF and FTY demonstrated similar effects on physical and cognitive neuroperformance and MRI outcomes. Direct comparisons to other fumarates and S1P receptor modulators were not conducted.

3.
Ann Clin Transl Neurol ; 8(11): 2166-2173, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34704393

RESUMEN

OBJECTIVE: To assess the independent contributions of clinical measures (relapses, Expanded Disability Status Scale [EDSS] scores, and neuroperformance measures) and nonclinical measures (new brain magnetic resonance imaging [MRI] activity and serum neurofilament light chain [sNfL] levels) for distinguishing natalizumab-treated from placebo-treated patients. METHODS: We conducted post hoc analyses using data from the AFFIRM trial of natalizumab for multiple sclerosis. We used multivariable regression analyses with predictors (EDSS progression, no relapse, new or enlarging MRI activity, brain atrophy, sNfL levels, and neuroperformance worsening) to identify measures that independently discriminated between treatment groups. RESULTS: The multivariable model that best distinguished natalizumab from placebo was no new or enlarging T2 or gadolinium-enhancing activity on MRI (odds ratio; 95% confidence interval: 7.2; 4.7-10.9), year 2 sNfL levels <97.5th percentile (4.1; 2.6-6.2), and no relapses in years 0-2 (2.1; 1.5-3.0). The next best-fitting model was a two-component model that included no MRI activity and sNfL levels <97.5th percentile at year 2. There was little difference between the three- and two-component models. INTERPRETATION: Nonclinical measures (new MRI activity and sNfL levels) discriminate between treatment and placebo groups similarly to or better than clinical outcomes composites and have implications for patient monitoring.


Asunto(s)
Factores Inmunológicos/farmacocinética , Esclerosis Múltiple Recurrente-Remitente/sangre , Esclerosis Múltiple Recurrente-Remitente/diagnóstico por imagen , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Natalizumab/farmacología , Evaluación de Resultado en la Atención de Salud , Adulto , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Proteínas de Neurofilamentos/sangre , Medicina de Precisión
4.
Mult Scler J Exp Transl Clin ; 7(2): 20552173211004634, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33948221

RESUMEN

BACKGROUND: Optimizing multiple sclerosis treatment warrants understanding of changes in physical, mental, and social health. OBJECTIVE: To assess the impact of natalizumab on Quality of Life in Neurological Disorders (Neuro-QoL) scores. METHODS: Annualized change in T-scores and likelihood of ≥5-point improvement over baseline were calculated for each Neuro-QoL domain after natalizumab initiation. Comparisons with ocrelizumab-treated patients were conducted after propensity score weighting and adjustment for relevant co-medications, year, and drug-year interaction. RESULTS: Among 164 natalizumab patients analyzed, 8 of 12 Neuro-QoL domains improved significantly, with greater improvement in patients with abnormal baseline Neuro-QoL. In the subgroup comparison of natalizumab-treated (n = 145) and ocrelizumab-treated (n = 520) patients, significant improvement occurred in 9 of 12 and 4 of 12 domains, respectively. The difference between groups was statistically significant for positive affect and well-being (p = 0.02), sleep (p = 0.003), and satisfaction with social roles and activities (SRA) (p = 0.03) in the overall population and for emotional and behavioral dyscontrol (p = 0.01), participation in SRA (p = 0.0001), and satisfaction with SRA (p = 0.02) in patients with abnormal baseline Neuro-QoL. CONCLUSIONS: Natalizumab can produce clinically meaningful improvements in mental and social health. Such improvements are unlikely to be primarily driven by expectation bias, as their magnitude exceeded improvements with another high-efficacy therapy, ocrelizumab.

5.
Neurol Ther ; 10(1): 169-182, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33225410

RESUMEN

INTRODUCTION: This post hoc subset analysis of RESPOND evaluated the effectiveness of dimethyl fumarate (DMF) 240 mg twice daily in patients with relapsing multiple sclerosis (RMS) after suboptimal response to glatiramer acetate (GA; "first switch" patients), including patients with early MS ("early MS switch" patients). METHODS: Patients had discontinued GA due to suboptimal response and initiated DMF treatment within 60 days after enrollment. Relapse data were collected from medical records. First switch patients had had one prior approved MS therapy (GA) before initiating DMF treatment. Early MS switch patients were first switch patients with baseline Patient-Reported Expanded Disability Status Scale (PR-EDSS) score ≤ 3.5, ≤ 1 relapses in the past 1 year, or both. RESULTS: Among first switch patients (n = 231), the annualized relapse rate (ARR) was 0.48 (95% confidence interval [CI] 0.40-0.58) for 12 months before DMF initiation and 0.11 (95% CI 0.06-0.18) for 12 months after DMF initiation, a 78% decrease in ARR. Among early MS switch patients with baseline PR-EDSS score ≤ 3.5 (n = 120), ≤ 1 relapses in the prior year (n = 219), or both (n = 114), the ARRs (95% CIs) for 12 months before DMF initiation were 0.47 (0.37-0.59), 0.37 (0.32-0.44), and 0.39 (0.31-0.49), respectively; values for 12 months after DMF initiation were 0.06 (0.02-0.19), 0.09 (0.05-0.17), and 0.06 (0.02-0.20), respectively, an 87, 75, and 83% decrease in ARR. The proportion of patients relapse-free 12 months after DMF initiation versus 12 months before were 94 versus 59% in first switch patients, and 97 versus 58%, 94 versus 63%, and 97 versus 61% in early MS switch patients in the PR-EDSS score ≤ 3.5, ≤ 1 relapses in the prior year, or PR-EDSS score ≤ 3.5 and ≤ 1 relapses subgroups, respectively. After 12 months of DMF treatment, most patient-reported outcomes scores showed significant improvement. CONCLUSIONS: DMF may be an effective treatment option in first switch and early MS switch patients with RMS who experience a suboptimal response to GA. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01903291.

6.
Mult Scler J Exp Transl Clin ; 6(2): 2055217320918619, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32440353

RESUMEN

BACKGROUND: In patients treated with dimethyl fumarate, absolute lymphocyte count decline typically occurs during the first year and then plateaus; early drops have been associated with the development of severe prolonged lymphopenia. OBJECTIVE: We investigated the effect of dimethyl fumarate on absolute lymphocyte counts and CD4+/CD8+ T cells in patients with relapsing-remitting multiple sclerosis treated with dimethyl fumarate in routine practice. METHODS: Lymphocyte data were collected via medical chart abstraction. Primary endpoint: change from baseline in absolute lymphocyte count and CD4+/CD8+ counts at 6-month intervals following dimethyl fumarate initiation. RESULTS: Charts of 483 patients were abstracted and 476 patients included in the analysis. Mean baseline absolute lymphocyte count (2.23 × 109/l) decreased by ∼39% (95% confidence interval: -41.1 to -37.2) by month 6 and 44% (95% confidence interval: -46.6 to -42.1) by month 12. CD4+ and CD8+ T-cell subsets strongly correlated with absolute lymphocyte count, with greater decreases from baseline to 6 months vs 6-12 months, and in CD8+ vs CD4+ T cells. Prior natalizumab was not a risk factor for lymphopenia. CONCLUSION: Dimethyl fumarate-associated decline in absolute lymphocyte count in the first 12 months correlated with decline in CD4+ and CD8+ T cells and was independent of prior natalizumab. Absolute lymphocyte count monitoring continues to be an effective strategy to identify patients at risk of prolonged lymphopenia.

7.
Neurol Ther ; 8(1): 109-119, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30706431

RESUMEN

INTRODUCTION: Delayed-release dimethyl fumarate (DMF) is an effective treatment for multiple sclerosis (MS). Some patients experience gastrointestinal (GI) adverse events (AEs) that may lead to premature DMF discontinuation. This study characterized the impact of site-specific GI management strategies on the occurrence of GI events and discontinuation patterns. METHODS: Data on GI events and DMF persistence were retrospectively abstracted from medical records of patients treated with DMF in routine medical practice in the EFFECT study (NCT02776072). GI management strategies were assessed via a study site questionnaire. Discontinuation rates were analyzed according to counseling patterns. RESULTS: Of 826 DMF-treated patients at 66 sites, 809 from 65 sites were eligible for the GI analysis; of these, 27% experienced GI AEs. Within 1 year of treatment, 14% (118/826) of patients discontinued DMF, 5% (44/809) due to GI events. Most sites (92%) reported that patients were very likely (> 75% of the time) to be counseled about GI events at/before DMF treatment initiation and/or to be recommended that DMF be taken with food (86%); 48% of sites reported to be very likely to recommend using symptomatic therapies for GI AEs. Lower discontinuation rates were reported at sites very likely versus not very likely (≤ 75% of the time) to (1) provide counseling; (2) provide specific details regarding GI events; or (3) recommend taking DMF with food, and/or using symptomatic GI therapies. CONCLUSION: Counseling and other GI management strategies at initiation of DMF treatment appear to reduce the burden of GI events, and a variety of GI management strategies may improve DMF persistence. TRIAL REGISTRATION: NCT02776072. FUNDING: Biogen (Cambridge, MA, USA).

8.
Clin Ther ; 40(12): 2021-2030.e1, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30447891

RESUMEN

PURPOSE: Flushing and gastrointestinal (GI) events are commonly associated with the use of delayed-release dimethyl fumarate (DMF) treatment for relapsing multiple sclerosis. METHODS: PREVENT (A Multicenter, Double-Blind, Placebo-Controlled Study of Pepto-Bismol [Bismuth Subsalicylate] on Gastrointestinal Tolerability in Healthy Volunteers Receiving Oral TECFIDERA [Dimethyl Fumarate] Delayed-Release Capsules Twice Daily) is a double-blind, placebo-controlled, 8-week study that evaluated the effect of bismuth subsalicylate on DMF-related GI events. Bismuth subsalicylate 524 mg or placebo were administered 30 min before DMF (weeks 1-4). DMF was dosed twice-daily (BID) at 120 mg (week 1) and 240 mg (weeks 2-8). Using an e-diary device, participants recorded GI and flushing events on the Modified Overall Gastrointestinal Symptom Scale once daily for the preceding 24 h. The primary end point was time to first GI-related event. Secondary end points included frequency and severity of GI-related events. FINDINGS: A total of 175 participants were enrolled (placebo, n = 87; bismuth subsalicylate, n = 88), and 17 discontinued treatment (placebo, n = 8; bismuth subsalicylate n = 9). A total of 146 participants reported ≥1 GI event: placebo, n = 72 (82.8%); and bismuth subsalicylate, n = 74 (84.1%). There was no statistical difference in risk of a GI event between the groups (P = 0.8292). Mean (SD) time from DMF initiation to first GI event was similar: placebo, 5.4 (8.73) days; and bismuth subsalicylate, 5.6 (10.87) days. Incidence of flatulence (38.6% vs 50.6%) and diarrhea (36.4% vs 48.2%) during weeks 1-4 was numerically lower in the bismuth subsalicylate group compared with the placebo group. Mean worst severity scores for flatulence (1.1 vs 1.8; P = 0.0219) and diarrhea (1.0 vs 1.6; P = 0.0500) were lower with bismuth subsalicylate than with placebo. IMPLICATIONS: Although coadministration of bismuth subsalicylate did not affect the occurrence of DMF-related GI events overall, it reduced the severity and incidence of flatulence and diarrhea. ClinicalTrials.gov identifier: NCT01915901.


Asunto(s)
Antidiarreicos/uso terapéutico , Bismuto/uso terapéutico , Diarrea/tratamiento farmacológico , Dimetilfumarato/efectos adversos , Inmunosupresores/efectos adversos , Compuestos Organometálicos/uso terapéutico , Salicilatos/uso terapéutico , Adolescente , Adulto , Preparaciones de Acción Retardada/uso terapéutico , Método Doble Ciego , Quimioterapia Combinada , Femenino , Flatulencia/tratamiento farmacológico , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Adulto Joven
9.
Am J Clin Nutr ; 92(4): 881-6, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20739426

RESUMEN

BACKGROUND: Supplementation in lactating HIV-1-infected women with preformed vitamin A and ß-carotene (VA/BC) increases the risk of mother-to-child transmission of HIV through breastfeeding. Identifying a biological mechanism to explain this unexpected finding would lend support to a causal effect. OBJECTIVE: The aim of the study was to evaluate the effect of VA/BC or multivitamin (B complex, vitamin C, and vitamin E) supplementation of HIV-infected women on HIV shedding in breast milk during the first 2 y postpartum. DESIGN: We quantified viral (cell-free) and proviral (cell-associated) HIV loads in breast-milk samples collected ≤15 d after delivery and every 3 mo thereafter from 594 Tanzanian HIV-1-infected women who participated in a randomized trial. Women received 1 of the following 4 daily oral regimens in a 2 × 2 factorial fashion during pregnancy and throughout the first 2 y postpartum: multivitamin, VA/BC, multivitamin including VA/BC, or placebo. RESULTS: The proportion of breast-milk samples with detectable viral load was significantly higher in women who received VA/BC (51.3%) than in women who were not assigned to VA/BC (44.8%; P = 0.02). The effect was apparent ≥6 mo postpartum (relative risk: 1.34; 95% CI: 1.04, 1.73). No associations with proviral load were observed. The multivitamin had no effects. In observational analyses, ß-carotene but not retinol breast-milk concentrations were significantly associated with an increased viral load in milk. CONCLUSIONS: VA/BC supplementation in lactating women increases the HIV load in breast milk. This finding contributes to explaining the adverse effect of VA/BC on mother-to-child transmission. ß-Carotene appears to have an effect on breast-milk viral load, independent of preformed vitamin A. This trial was registered at clinicaltrials.gov as NCT00197756.


Asunto(s)
Suplementos Dietéticos , VIH/aislamiento & purificación , Leche Humana/virología , Esparcimiento de Virus/efectos de los fármacos , Vitamina A/farmacología , Vitaminas/farmacología , beta Caroteno/farmacología , Lactancia Materna/efectos adversos , Femenino , VIH/efectos de los fármacos , Infecciones por VIH/epidemiología , Infecciones por VIH/transmisión , Humanos , Embarazo , Factores de Riesgo , Tanzanía , Carga Viral , Vitamina A/efectos adversos , beta Caroteno/efectos adversos
10.
J Infect Dis ; 202(3): 370-3, 2010 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-20557236

RESUMEN

We examined the prospective associations between breast milk concentrations of erythropoietin, a factor with trophic effects on infant gut epithelia, and the risk of mother-to-child transmission (MTCT) of human immunodeficiency virus (HIV) through breast-feeding in a study of 59 MTCT cases and 116 controls nested within a cohort of antiretroviral-naive HIV-infected Tanzanian women. Controls were matched to cases on the basis of the time from birth when the breast milk sample was collected. The risk of MTCT was inversely related to breast milk erythropoietin concentration (adjusted odds ratio for highest vs lowest erythropoietin concentration tertile, 0.34 [95% confidence interval, 0.14-0.82]; P = .02). These results suggest a protective effect of breast milk erythropoietin against MTCT.


Asunto(s)
Eritropoyetina/análisis , Infecciones por VIH/transmisión , Transmisión Vertical de Enfermedad Infecciosa , Leche Humana/química , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Lactante , Recién Nacido , Embarazo , Estudios Prospectivos , Medición de Riesgo , Tanzanía
11.
J Acquir Immune Defic Syndr ; 46(5): 651-4, 2007 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-18043320

RESUMEN

BACKGROUND: Mastitis has been identified as a risk factor for mother-to-child transmission (MTCT) of HIV-1 through breast-feeding. It is unclear whether this association is mediated by increased cell-free virus (CFV) versus cell-associated virus (CAV) HIV shedding in breast milk. METHODS: We examined the risk of MTCT associated with subclinical mastitis and the relation between mastitis and CFV or CAV shedding in breast milk. Fifty-nine women who transmitted HIV through breast-feeding (cases) were individually matched to 59 nontransmitting controls nested in a cohort from Tanzania. For each case, we selected a milk specimen obtained before the infant's first positive test to quantify sodium (Na) and potassium (K) and measure CFV and CAV concentrations. Controls were matched on the child's age at the time of sample collection. RESULTS: Women with a breast milk Na/K ratio suggestive of mastitis (>1.0) had an 11-fold greater odds of transmission (95% confidence interval [CI]: 1.2 to 98.1), compared to women with a Na/K

Asunto(s)
Lactancia Materna , Infecciones por VIH/transmisión , Transmisión Vertical de Enfermedad Infecciosa , Leucocitos/virología , Mastitis , Leche Humana/virología , Esparcimiento de Virus , Estudios de Casos y Controles , Femenino , VIH-1/aislamiento & purificación , Humanos , Recién Nacido , Leche Humana/química , Leche Humana/citología , Potasio/análisis , Embarazo , Sodio/análisis , Tanzanía/epidemiología
12.
Am J Clin Nutr ; 86(3): 682-9, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17823433

RESUMEN

BACKGROUND: Breastfeeding accounts for a sizable proportion of infant HIV infections. Some fatty acids (FAs) are potent immunomodulators with virucidal activity, and their primary source in breastfed children is breast milk. OBJECTIVES: The aims of the study were to examine whether the percentage weight concentration of FAs in breast milk was associated with the risk of mother-to-child transmission (MTCT) of HIV by breastfeeding and with shedding of cell-free virus (CFV) or cell-associated virus (CAV) in breast milk. DESIGN: We conducted a case-control study nested within a cohort of HIV-infected Tanzanian women and children. We matched 59 incident breastfeeding MTCT cases to 59 nontransmitting controls based on the child's age at sample collection. We quantified FAs, CFV, and CAV in a breast milk sample collected before the infant's first positive HIV test. RESULTS: After adjustment for indicators of maternal HIV disease stage, the risk of MTCT was inversely related to 11c,14c-eicosadienoic acid [odds ratio (OR) for quartile 4 compared with quartile 1: 0.21; P for trend = 0.04], arachidonic acid (OR: 0.21; P for trend = 0.03), and dihomo-gamma-linolenic acid (OR: 0.24; P for trend = 0.03); the latter 2 were also linearly, inversely related to virus shedding in breast milk. Lauric acid and pentadecanoic acid were associated with increased MTCT, whereas trans FAs were related to higher CAV and CFV. CONCLUSION: Increasing concentrations of long-chain n-6 polyunsaturated FAs in breast milk might reduce the risk of MTCT.


Asunto(s)
Ácidos Grasos Omega-6/análisis , Infecciones por VIH/transmisión , VIH-1 , Leche Humana/química , Leche Humana/virología , Esparcimiento de Virus , Adulto , Ácidos Araquidónicos/análisis , Lactancia Materna/efectos adversos , Estudios de Casos y Controles , Sistema Libre de Células , Estudios de Cohortes , Ácido Eicosapentaenoico/análisis , Ácidos Grasos/análisis , Ácidos Grasos Omega-6/inmunología , Femenino , Infecciones por VIH/prevención & control , VIH-1/aislamiento & purificación , Humanos , Lactante , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Ácidos Láuricos/análisis , Tanzanía/epidemiología , Ácido gammalinolénico/análisis
13.
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
14.
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
15.
AIDS Res Hum Retroviruses ; 21(10): 897-900, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16225419

RESUMEN

We recently identified an HIV-1 subtype C and D circulating recombinant form (CRF10_CD) in infants in Dar es Salaam, Tanzania. So far, this is the only reported HIV-1 CRF in East Africa. However, evidence for its spread in the adult population is scarce. Here we describe the presence of CRF10_CD in two asymptomatic bar and hotel workers in Moshi, Northern Tanzania. Subgenomic sequences from gag (3'p24-5'p7), env (C2-C5), and the 5' LTR were used for phylogenetic analysis and identification of recombination. Genetic divergence between the CRF10_CD sequences from Moshi suggested that they were contracted from independent sources. A third bar worker was infected with an apparent CRF10_CD/subtype A recombinant virus. Our data indicate that CRF10_CD genomes can be transmitted both vertically and heterosexually.


Asunto(s)
VIH-1/aislamiento & purificación , Variación Genética , Genoma Viral , VIH-1/clasificación , VIH-1/genética , Humanos , Filogenia , Recombinación Genética , Tanzanía
16.
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
17.
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
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