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1.
Cell ; 150(3): 533-48, 2012 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-22863007

RESUMEN

Nephronophthisis-related ciliopathies (NPHP-RC) are degenerative recessive diseases that affect kidney, retina, and brain. Genetic defects in NPHP gene products that localize to cilia and centrosomes defined them as "ciliopathies." However, disease mechanisms remain poorly understood. Here, we identify by whole-exome resequencing, mutations of MRE11, ZNF423, and CEP164 as causing NPHP-RC. All three genes function within the DNA damage response (DDR) pathway. We demonstrate that, upon induced DNA damage, the NPHP-RC proteins ZNF423, CEP164, and NPHP10 colocalize to nuclear foci positive for TIP60, known to activate ATM at sites of DNA damage. We show that knockdown of CEP164 or ZNF423 causes sensitivity to DNA damaging agents and that cep164 knockdown in zebrafish results in dysregulated DDR and an NPHP-RC phenotype. Our findings link degenerative diseases of the kidney and retina, disorders of increasing prevalence, to mechanisms of DDR.


Asunto(s)
Daño del ADN , Proteínas de Unión al ADN/metabolismo , Exoma , Enfermedades Renales Quísticas/genética , Proteínas de Microtúbulos/metabolismo , Animales , Cilios/metabolismo , Técnicas de Silenciamiento del Gen , Genes Recesivos , Humanos , Proteína Homóloga de MRE11 , Ratones , Proteínas , Transducción de Señal , Pez Cebra/embriología , Pez Cebra/metabolismo
2.
J Infect Dis ; 227(2): 268-277, 2023 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-35776140

RESUMEN

BACKGROUND: From 2019 to 2021, Rwandan residents of the border with the Democratic Republic of the Congo were offered the Ad26.ZEBOV (adenovirus type 26 vector vaccine encoding Ebola virus glycoprotein) and MVA-BN-Filo (modified vaccinia virus Ankara vector vaccine, encoding glycoproteins from Ebola, Sudan, Marburg, and nucleoprotein from Tai Forest viruses) Ebola vaccine regimen. METHODS: Nonpregnant persons aged ≥2 years were eligible. Unsolicited adverse events (UAEs) were reported through phone calls or visits, and serious adverse events (SAEs) were recorded per International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines. RESULTS: Following Ad26.ZEBOV, UAEs were reported by 0.68% of 216 113 vaccinees and were more common in younger children (aged 2-8 years, 1.2%) compared with older children (aged 9-17 years, 0.4%) and adults (aged ≥18 years, 0.7%). Fever and headache were the most reported symptoms. All 17 SAEs related to vaccine were in children aged 2-8 years (10 postvaccination febrile convulsions ± gastroenteritis and 7 fever and/or gastroenteritis). The incidence of febrile seizures was 8 of 26 062 (0.031%) prior to initiation of routine acetaminophen in December 2020 and 2 of 15 897 (0.013%) thereafter. Nonobstetric SAEs were similar in males and females. All 20 deaths were unrelated to vaccination. Young girls and adult women with UAEs were less likely to receive the second dose than those without UAEs. Seven unrelated SAEs occurred in 203 267 MVA-BN-Filo recipients. CONCLUSIONS: Postvaccination febrile convulsions in young children were rare but not previously described after Ad26.ZEBOV and were reduced with routine acetaminophen. The regimen was otherwise safe and well-tolerated.


Asunto(s)
Vacunas contra el Virus del Ébola , Ebolavirus , Fiebre Hemorrágica Ebola , Convulsiones Febriles , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Masculino , Acetaminofén , Anticuerpos Antivirales , Vacunas contra el Virus del Ébola/efectos adversos , Glicoproteínas , Fiebre Hemorrágica Ebola/prevención & control , Convulsiones Febriles/inducido químicamente , Vacunación/efectos adversos , Virus Vaccinia
3.
Arch Sex Behav ; 52(6): 2649-2667, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37024634

RESUMEN

Negotiating sexual agreements in combination with couples' voluntary HIV counseling and testing (CVCT) may help further reduce HIV transmission in Zambian concordant HIV-negative couples (CNC). Though CVCT has been shown to reduce HIV transmission in CNC by 47%, approximately half of residual infections occur in this group. We developed a "Strengthening Our Vows" video session to foster communication and negotiation of explicit sexual agreements to reduce concurrent sexual exposures and prevent HIV transmission to the spouse due to unprotected, extramarital sex. CNC were recruited through CVCT services at five clinics in Lusaka and Ndola in 2016. Enrolled CNC attending the facilitated group video sessions were encouraged to discuss sexual agreements at home and return 1-2 weeks later for follow-up assessment. One-fourth of the 580 CNC returning reported a history of extramarital partners and/or a sexually transmitted infection (STI) prior to enrollment. More than 95% reported a friendly, supportive 15-60 min negotiation culminating in an agreement to remain monogamous or disclose sexual contacts and use condoms together until a repeat HIV test 30 days after an outside sexual exposure. Two-thirds of participants identified at least one threat to adherence of their agreements including alcohol use, financial pressures, travel, discord in the home, and post-partum or menstrual abstinence. CNC negotiated explicit sexual agreements to avoid exposure to HIV through concurrent partnerships and protect the spouse in the event of an outside sexual contact. Open communication was a consistent theme to facilitate mutual protective efforts. Long-term follow-up of HIV/STI incidence is ongoing to assess the impact of these agreements.Trial registration This sub-study is part of a trial retrospectively registered on ClinicalTrials.gov (Identifier: NCT02744586) on April 20, 2016.


Asunto(s)
Infecciones por VIH , Enfermedades de Transmisión Sexual , Femenino , Humanos , Heterosexualidad , Infecciones por VIH/prevención & control , Negociación , Conducta Sexual/psicología , Parejas Sexuales/psicología , Enfermedades de Transmisión Sexual/prevención & control , Zambia , Masculino
4.
PLoS Pathog ; 16(6): e1008378, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32492044

RESUMEN

The HIV-1 reservoir consists of latently infected cells that persist despite antiretroviral therapy (ART). Elucidating the proviral genetic composition of the reservoir, particularly in the context of pre-therapy viral diversity, is therefore important to understanding reservoir formation and the persistence of latently infected cells. Here we investigate reservoir proviral variants from 13 Zambian acutely-infected individuals with additional pre-therapy sampling for a unique comparison to the ART-naïve quasispecies. We identified complete transmitted/founder (TF) viruses from seroconversion plasma samples, and additionally amplified and sequenced HIV-1 from plasma obtained one year post-infection and just prior to ART initiation. While the majority of proviral variants in the reservoir were most closely related to viral variants from the latest pre-therapy time point, we also identified reservoir proviral variants dating to or near the time of infection, and to intermediate time points between infection and treatment initiation. Reservoir proviral variants differing by five or fewer nucleotide changes from the TF virus persisted during treatment in five individuals, including proviral variants that exactly matched the TF in two individuals, one of whom had remained ART-naïve for more than six years. Proviral variants during treatment were significantly less divergent from the TF virus than plasma variants present at the last ART-naïve time point. These findings indicate that reservoir proviral variants are archived throughout infection, recapitulating much of the viral diversity that arises throughout untreated HIV-1 infection, and strategies to target and reduce the reservoir must therefore permit for the clearance of proviruses encompassing this extensive diversity.


Asunto(s)
Variación Genética , Infecciones por VIH/genética , VIH-1/genética , Filogenia , Enfermedad Aguda , Adulto , Antirretrovirales , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/metabolismo , VIH-1/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Zambia
5.
Sex Transm Infect ; 98(3): 178-187, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-33958492

RESUMEN

BACKGROUND: STIs among men who have sex with men (MSM) and transgender women (TGW) continue to increase. In Rwanda, STI management relies on syndromic management with limited empirical data characterising the burden of specific STIs among MSM/TGW. This study evaluated the prevalence of syphilis, Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) and associated factors among MSM/TGW in Kigali. METHODS: From March to August 2018, 737 MSM/TGW >18 years were enrolled using respondent-driven sampling (RDS). Structured interviews and HIV/STI screening were conducted. Syphilis was screened with rapid plasma reagin confirmed by Treponema pallidum hemagglutination assay. CT/NG were tested by Cepheid GeneXpert. RDS-adjusted multivariable Poisson regression models with robust variance estimation were used to evaluate factors associated with any STI, and determinants of urethral and rectal STIs separately. RESULTS: Prevalence of any STI was 20% (RDS adjusted: 16.7% (95% CI: 13.2% to 20.2%)). Syphilis was 5.7% (RDS adjusted: 6.8% (95% CI: 4.3% to 9.4%)). CT was 9.1% (RDS adjusted: 6.1% (95% CI: 3.9% to 8.4%)) and NG was 8.8% (RDS adjusted: 7.1% (95% CI: 4.9% to 9.2%)). STIs were more common among older MSM and those with HIV (p<0.05). Of CT infections, 67% were urethral, 27% rectal and 6% were dual site. For NG infections, 52% were rectal, 29% urethral and 19% were dual site. Overall, 25.8% (23 of 89) of those with confirmed STI and returned for their results were symptomatic at time of testing.STI symptoms in the previous year (adjusted prevalence ratio (aPR): 1.94 (95% CI: 1.26 to 2.98)) were positively associated with any STI. Being circumcised was negatively associated with any STI (aPR: 0.47 (95% CI: 0.31 to 0.73)). HIV was positively associated with rectal STIs (aPR: 3.50 (95% CI: 1.09 to 11.21)) but negatively associated with urethral STIs. CONCLUSION: MSM/TGW, especially those living with HIV, are at high risk of STIs in Rwanda with the vast majority being asymptomatic. These data suggest the potential utility of active STI surveillance strategies using highly sensitive laboratory methods among those at high risk given the anatomical distribution and limited symptomatology of STIs observed among Rwandan MSM/TGW.


Asunto(s)
Infecciones por Chlamydia , Gonorrea , Infecciones por VIH , Minorías Sexuales y de Género , Enfermedades de Transmisión Sexual , Sífilis , Personas Transgénero , Infecciones por Chlamydia/epidemiología , Chlamydia trachomatis , Estudios Transversales , Femenino , Gonorrea/diagnóstico , Gonorrea/epidemiología , Infecciones por VIH/prevención & control , Homosexualidad Masculina , Humanos , Masculino , Neisseria gonorrhoeae , Prevalencia , Rwanda/epidemiología , Enfermedades de Transmisión Sexual/diagnóstico , Enfermedades de Transmisión Sexual/epidemiología , Sífilis/diagnóstico , Sífilis/epidemiología
6.
AIDS Behav ; 26(2): 470-477, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34333718

RESUMEN

Observing sexual behaviour change over time could help develop behavioural HIV prevention interventions for female sex workers in Zambia, where these interventions are lacking. We investigated the evolution of consistent condom use among female sex workers and their clients and steady partners. Participants were recruited into an HIV incidence cohort from 2012 to 2017. At each visit, women received HIV counselling and testing, screening for sexually transmitted infections (STIs) and free condoms. Our outcome was reported consistent (100%) condom use in the previous month with steady partners, repeat clients, and non-repeat clients. Consistent condom use at baseline was highest with non-repeat clients (36%) followed by repeat clients (27%) and steady partners (17%). Consistent condom use between baseline and Month 42 increased by 35% with steady partners, 39% with repeat clients and 41% with non-repeat clients. Access to condoms, HIV/STI counselling and testing promoted positive sexual behaviour change.


Asunto(s)
Infecciones por VIH , Trabajadores Sexuales , Enfermedades de Transmisión Sexual , Condones , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Humanos , Conducta Sexual , Enfermedades de Transmisión Sexual/epidemiología , Enfermedades de Transmisión Sexual/prevención & control , Zambia/epidemiología
7.
J Aging Soc Policy ; 34(5): 690-706, 2022 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-35959862

RESUMEN

The Veterans Health Administration (VHA) long-term care rebalancing initiative encouraged VA Community Living Centers (CLCs) to shift from long-stay custodial-focused care to short-stay skilled and rehabilitative care. Using all VA CLC admissions during 2007-2010 categorized as needing short-stay rehabilitation or skilled nursing care, we assessed the patient and facility rates of successful discharge to the community (SDC) of these short-stay Veterans. We found large variation in inter- as well as intra- facility SDC rates across the rehabilitation and skilled nursing short-stay cohorts. We discuss how our results can help guide VHA policy directed at delivering high-quality short-stay CLC care for Veterans.


Asunto(s)
Veteranos , Humanos , Cuidados a Largo Plazo , Alta del Paciente , Estados Unidos , United States Department of Veterans Affairs
8.
J Infect Dis ; 224(1): 81-91, 2021 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-33560366

RESUMEN

BACKGROUND: We explored the role of genital abnormalities and hormonal contraception in human immunodeficiency virus (HIV) transmission among heterosexual serodifferent couples in Rwanda. METHODS: From 2002 to 2011, HIV-serodifferent couples who were not using antiretroviral treatment were followed up, and sociodemographic and clinical data were collected, family planning provided, and HIV-negative partners retested. Couples were assessed for genital ulcers; nonulcerative genital sexually transmitted infection (STIs), including gonorrhea, chlamydia, and trichomoniasis; and non-STI vaginal infections, including bacterial vaginosis and candida. Multivariable models evaluated associations between covariates and HIV transmission genetically linked to the index partner. RESULTS: Among 877 couples in which the man was HIV positive, 37 linked transmissions occurred. Factors associated with women's HIV acquisition included genital ulceration in the female partner (adjusted hazard ratio, 14.1) and nonulcerative STI in the male partner (8.6). Among 955 couples in which the woman was HIV positive, 46 linked transmissions occurred. Factors associated with HIV acquisition in men included nonulcerative STI in the female partner (adjusted hazard ratio, 4.4), non-STI vaginal dysbiosis (7.1), and genital ulceration in the male partner (2.6). Hormonal contraception use was not associated with HIV transmission or acquisition. CONCLUSIONS: Our findings underscore the need for integrating HIV services with care for genital abnormalities. Barriers (eg, cost of training, demand creation, advocacy, and client education; provider time; and clinic space) to joint HIV/STI testing need to be considered and addressed.


Asunto(s)
Enfermedades de los Genitales Femeninos/complicaciones , Infecciones por VIH/transmisión , Anticoncepción Hormonal/métodos , Enfermedades de Transmisión Sexual/complicaciones , Adulto , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/etiología , Humanos , Masculino , Factores de Riesgo , Estudios Seroepidemiológicos
9.
J Neurosci ; 40(49): 9455-9466, 2020 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-33158965

RESUMEN

Gonadal steroids modulate growth hormone (GH) secretion and the pubertal growth spurt via undefined central pathways. GH-releasing hormone (GHRH) neurons express estrogen receptor α (ERα) and androgen receptor (AR), suggesting changing levels of gonadal steroids during puberty directly modulate the somatotropic axis. We generated mice with deletion of ERα in GHRH cells (GHRHΔERα), which displayed reduced body length in both sexes. Timing of puberty onset was similar in both groups, but puberty completion was delayed in GHRHΔERα females. Lack of AR in GHRH cells (GHRHΔAR mice) induced no changes in body length, but puberty completion was also delayed in females. Using a mouse model with two reporter genes, we observed that, while GHRHtdTom neurons minimally colocalize with Kiss1hrGFP in prepubertal mice, ∼30% of GHRH neurons coexpressed both reporter genes in adult females, but not in males. Developmental analysis of Ghrh and Kiss1 expression suggested that a subpopulation of ERα neurons in the arcuate nucleus of female mice undergoes a shift in phenotype, from GHRH to Kiss1, during pubertal transition. Our findings demonstrate that direct actions of gonadal steroids in GHRH neurons modulate growth and puberty and indicate that GHRH/Kiss1 dual-phenotype neurons play a sex-specific role in the crosstalk between the somatotropic and gonadotropic axes during pubertal transition.SIGNIFICANCE STATEMENT Late maturing adolescents usually show delayed growth and bone age. At puberty, gonadal steroids have stimulatory effects on the activation of growth and reproductive axes, but the existence of gonadal steroid-sensitive neuronal crosstalk remains undefined. Moreover, the neural basis for the sex differences observed in the clinical arena is unknown. Lack of ERα in GHRH neurons disrupts growth in both sexes and causes pubertal delay in females. Deletion of androgen receptor in GHRH neurons only delayed female puberty. In adult females, not males, a subset of GHRH neurons shift phenotype to start producing Kiss1. Thus, direct estrogen action in GHRH/Kiss1 dual-phenotype neurons modulates growth and puberty and may orchestrate the sex differences in endocrine function observed during pubertal transition.


Asunto(s)
Receptor alfa de Estrógeno/fisiología , Hormona Liberadora de Hormona del Crecimiento/fisiología , Crecimiento/fisiología , Kisspeptinas/fisiología , Maduración Sexual/fisiología , Transducción de Señal/fisiología , Animales , Receptor alfa de Estrógeno/genética , Femenino , Hormonas Esteroides Gonadales/sangre , Hormonas Esteroides Gonadales/fisiología , Crecimiento/genética , Hormona Liberadora de Hormona del Crecimiento/genética , Hipotálamo/metabolismo , Kisspeptinas/genética , Masculino , Ratones , Ratones Noqueados , Receptores Androgénicos/fisiología , Caracteres Sexuales , Maduración Sexual/genética , Transducción de Señal/genética
10.
Clin Infect Dis ; 73(5): 832-841, 2021 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-33588436

RESUMEN

BACKGROUND: Acute retroviral syndrome (ARS) is associated with human immunodeficiency virus type 1 (HIV-1) subtype and disease progression, but the underlying immunopathological pathways are poorly understood. We aimed to elucidate associations between innate immune responses during hyperacute HIV-1 infection (hAHI) and ARS. METHODS: Plasma samples obtained from volunteers (≥18.0 years) before and during hAHI, defined as HIV-1 antibody negative and RNA or p24 antigen positive, from Kenya, Rwanda, Uganda, Zambia, and Sweden were analyzed. Forty soluble innate immune markers were measured using multiplexed assays. Immune responses were differentiated into volunteers with stronger and comparatively weaker responses using principal component analysis. Presence or absence of ARS was defined based on 11 symptoms using latent class analysis. Logistic regression was used to determine associations between immune responses and ARS. RESULTS: Of 55 volunteers, 31 (56%) had ARS. Volunteers with stronger immune responses (n = 36 [65%]) had increased odds of ARS which was independent of HIV-1 subtype, age, and risk group (adjusted odds ratio, 7.1 [95% confidence interval {CI}: 1.7-28.8], P = .003). Interferon gamma-induced protein (IP)-10 was 14-fold higher during hAHI, elevated in 7 of the 11 symptoms and independently associated with ARS. IP-10 threshold >466.0 pg/mL differentiated stronger immune responses with a sensitivity of 84.2% (95% CI: 60.4-96.6) and specificity of 100.0% (95% CI]: 90.3-100.0). CONCLUSIONS: A stronger innate immune response during hAHI was associated with ARS. Plasma IP-10 may be a candidate biomarker of stronger innate immunity. Our findings provide further insights on innate immune responses in regulating ARS and may inform the design of vaccine candidates harnessing innate immunity.


Asunto(s)
Síndrome Retroviral Agudo , Infecciones por VIH , VIH-1 , Quimiocina CXCL10 , Humanos , Inmunidad Innata
11.
Retrovirology ; 18(1): 8, 2021 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-33731158

RESUMEN

BACKGROUND: To determine if individuals, from HIV-1 serodiscordant couple cohorts from Rwanda and Zambia, who become HIV-positive have a distinct inflammatory biomarker profile compared to individuals who remain HIV-negative, we compared levels of biomarkers in plasma of HIV-negative individuals who either seroconverted (pre-infection) and became HIV-positive or remained HIV-negative (uninfected). RESULTS: We observed that individuals in the combined cohort, as well as those in the individual country cohorts, who later became HIV-1 infected had significantly higher baseline levels of multiple inflammatory cytokines/chemokines compared to individuals who remained HIV-negative. Genital inflammation/ulceration or schistosome infections were not associated with this elevated profile. Defined levels of ITAC and IL-7 were significant predictors of later HIV acquisition in ROC predictive analyses, whereas the classical Th1 and Th2 inflammatory cytokines such as IL-12 and interferon-γ or IL-4, IL-5 and Il-13 were not. CONCLUSIONS: Overall, the data show a significant association between increased plasma biomarkers linked to inflammation and immune activation and HIV acquisition and suggests that pre-existing conditions that increase systemic biomarkers represent a factor for increased risk of HIV infection.


Asunto(s)
Citocinas/sangre , Infecciones por VIH/sangre , Infecciones por VIH/diagnóstico , VIH-1/inmunología , Inflamación/sangre , Biomarcadores/sangre , Estudios de Cohortes , Femenino , Humanos , Inflamación/virología , Masculino , Factores de Riesgo , Rwanda , Zambia
12.
J Virol ; 94(16)2020 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-32461316

RESUMEN

The influence of biological sex on disease progression in HIV-1-infected individuals has been focused on the chronic stage of infection, but little is known about how sex differences influence acute HIV-1 infection. We observed profound differences in viral load and CD4+ T cell activation from the earliest time points in men and women in a Zambian heterosexual acute infection cohort. Women exhibited a >2-fold higher rate of CD4+ T cell loss despite significantly lower viral loads (VL) than men. The importance of studying acute infection was highlighted by the observation that very early in infection, women exhibited significantly higher levels of CD4+ T cell activation, a difference that was lost over the first 3 years of infection as activation in men increased. In women, activation of CD4+ T cells in the acute phase was significantly correlated with plasma levels of 17ß-estradiol (E2). However, unlike in men, higher CD4+ T cell activation in women was not associated with higher VL. In contrast, a higher E2 level in early infection was associated with lower early and set-point VL in women. We attribute this to an inhibitory effect of estradiol on virus replication, which we were able to observe with relevant transmitted/founder viruses in vitro Thus, estradiol plays a key role in defining major differences between men and women during early HIV-1 infection by contributing to both viral control and CD4+ T cell loss, an effect that extends into the chronic phase of the disease.IMPORTANCE Previous studies have identified sex-specific differences during chronic HIV-1 infection, but little is known about sex differences in the acute phase, or how disparities in the initial response to the virus may affect disease. We demonstrate that restriction of viral load in women begins during acute infection and is maintained into chronic infection. Despite this, women exhibit more rapid CD4+ T cell loss than men. These profound differences are influenced by 17ß-estradiol, which contributes both to T cell activation and to reduced viral replication. Thus, we conclude that estradiol plays a key role in shaping responses to early HIV-1 infection that influence the chronic phase of disease.


Asunto(s)
Estradiol/farmacología , Infecciones por VIH/tratamiento farmacológico , Carga Viral/efectos de los fármacos , Adulto , Recuento de Linfocito CD4 , Linfocitos T CD4-Positivos/inmunología , Estudios de Cohortes , Progresión de la Enfermedad , Estradiol/metabolismo , Femenino , Hormonas Esteroides Gonadales/farmacología , Infecciones por VIH/metabolismo , Infecciones por VIH/virología , VIH-1/metabolismo , VIH-1/patogenicidad , Humanos , Activación de Linfocitos , Masculino , Replicación Viral , Zambia/epidemiología
13.
J Virol ; 94(14)2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32376625

RESUMEN

Downregulation of BST-2/tetherin and CD4 by HIV-1 viral protein U (Vpu) promotes viral egress and allows infected cells to evade host immunity. Little is known however about the natural variability in these Vpu functions among the genetically diverse viral subtypes that contribute to the HIV-1 pandemic. We collected Vpu isolates from 332 treatment-naive individuals living with chronic HIV-1 infection in Uganda, Rwanda, South Africa, and Canada. Together, these Vpu isolates represent four major HIV-1 group M subtypes (A [n = 63], B [n = 84], C [n = 94], and D [n = 59]) plus intersubtype recombinants and uncommon strains (n = 32). The ability of each Vpu clone to downregulate endogenous CD4 and tetherin was quantified using flow cytometry following transfection into an immortalized T-cell line and compared to that of a reference Vpu clone derived from HIV-1 subtype B NL4.3. Overall, the median CD4 downregulation function of natural Vpu isolates was similar to that of NL4.3 (1.01 [interquartile range {IQR}, 0.86 to 1.18]), while the median tetherin downregulation function was moderately lower than that of NL4.3 (0.90 [0.79 to 0.97]). Both Vpu functions varied significantly among HIV-1 subtypes (Kruskal-Wallis P < 0.0001). Specifically, subtype C clones exhibited the lowest CD4 and tetherin downregulation activities, while subtype D and B clones were most functional for both activities. We also identified Vpu polymorphisms associated with CD4 or tetherin downregulation function and validated six of these using site-directed mutagenesis. Our results highlight the marked extent to which Vpu function varies among global HIV-1 strains, raising the possibility that natural variation in this accessory protein may contribute to viral pathogenesis and/or spread.IMPORTANCE The HIV-1 accessory protein Vpu enhances viral spread by downregulating CD4 and BST-2/tetherin on the surface of infected cells. Natural variability in these Vpu functions may contribute to HIV-1 pathogenesis, but this has not been investigated among the diverse viral subtypes that contribute to the HIV-1 pandemic. In this study, we found that Vpu function differs significantly among HIV-1 subtypes A, B, C, and D. On average, subtype C clones displayed the lowest ability to downregulate both CD4 and tetherin, while subtype B and D clones were more functional. We also identified Vpu polymorphisms that associate with functional differences among HIV-1 isolates and subtypes. Our study suggests that genetic diversity in Vpu may play an important role in the differential pathogenesis and/or spread of HIV-1.


Asunto(s)
Antígenos CD/biosíntesis , Antígenos CD4/biosíntesis , Regulación hacia Abajo , Infecciones por VIH , VIH-1/metabolismo , Proteínas del Virus de la Inmunodeficiencia Humana/metabolismo , Proteínas Reguladoras y Accesorias Virales/metabolismo , Antígenos CD/genética , Antígenos CD4/genética , Línea Celular Transformada , Enfermedad Crónica , Proteínas Ligadas a GPI/biosíntesis , Proteínas Ligadas a GPI/genética , VIH-1/genética , Proteínas del Virus de la Inmunodeficiencia Humana/genética , Humanos , Proteínas Reguladoras y Accesorias Virales/genética
14.
PLoS Pathog ; 15(8): e1007981, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31449552

RESUMEN

Despite extensive research on the mechanisms of HLA-mediated immune control of HIV-1 pathogenesis, it is clear that much remains to be discovered, as exemplified by protective HLA alleles like HLA-B*81 which are associated with profound protection from CD4+ T cell decline without robust control of early plasma viremia. Here, we report on additional HLA class I (B*1401, B*57, B*5801, as well as B*81), and HLA class II (DQB1*02 and DRB1*15) alleles that display discordant virological and immunological phenotypes in a Zambian early infection cohort. HLA class I alleles of this nature were also associated with enhanced immune responses to conserved epitopes in Gag. Furthermore, these HLA class I alleles were associated with reduced levels of lipopolysaccharide (LPS) in the plasma during acute infection. Elevated LPS levels measured early in infection predicted accelerated CD4+ T cell decline, as well as immune activation and exhaustion. Taken together, these data suggest novel mechanisms for HLA-mediated immune control of HIV-1 pathogenesis that do not necessarily involve significant control of early viremia and point to microbial translocation as a direct driver of HIV-1 pathogenesis rather than simply a consequence.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Genes MHC Clase I/genética , Infecciones por VIH/inmunología , VIH-1/inmunología , VIH-1/patogenicidad , Lipopolisacáridos/deficiencia , Replicación Viral/inmunología , Alelos , Estudios de Cohortes , Femenino , Infecciones por VIH/genética , Infecciones por VIH/virología , VIH-1/genética , Humanos , Masculino , Linfocitos T Citotóxicos/inmunología , Carga Viral , Replicación Viral/genética
15.
Sex Transm Dis ; 48(6): 424-428, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33433171

RESUMEN

BACKGROUND: Antiretroviral therapy (ART) efficacy for HIV prevention among discordant couples has been demonstrated in clinical trials. Effectiveness outside of research settings is less well understood. METHODS: HIV-discordant couples were enrolled in couples' testing and follow-up at 20 government clinics in Kigali from 2010 to 2014. We performed viral linkage analysis on seroconverting couples to determine infection sources (intracouple vs. extracouple). Antiretroviral therapy use in index partners was collected at baseline and during follow-up by self-report with verification of government medical records. RESULTS: A total of 3777 HIV-discordant couples were identified and followed up at government health clinics. Fifty-four incident HIV infections were identified, of which 36 were confirmed linked to the index partner, 4 were unlinked, and 14 were unknown. Among the 50 linked or unknown transmission pairs, 38% occurred among couples in which the index partner was on ART (HIV incidence rate of 0.63/100 person-years), whereas 62% occurred among couples in which the index partner was not on ART (HIV incidence rate of 5.51/100 person-years; adjusted rate ratio, 6.9). HIV acquisition was higher in women than in men with non-ART using index partners (P < 0.001). CONCLUSIONS: Couples in a government clinic couples' HIV testing and follow-up program in Rwanda had an 89% reduction in HIV incidence when index partners were using ART, slightly lower than efficacy estimates from randomized trials. Antiretroviral therapy for prevention should be prioritized for key populations including discordant couples identified via couples' voluntary counseling and testing, with increased efforts to improve uptake, adherence, and viral load monitoring.


Asunto(s)
Infecciones por VIH , Consejo , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Humanos , Masculino , Rwanda/epidemiología , Parejas Sexuales , Carga Viral
16.
BMC Infect Dis ; 21(1): 392, 2021 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-33910514

RESUMEN

BACKGROUND: Algorithms that bridge the gap between syndromic sexually transmitted infection (STI) management and treatment based in realistic diagnostic options and local epidemiology are urgently needed across Africa. Our objective was to develop and validate a risk algorithm for Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) diagnosis among symptomatic Rwandan women and to compare risk algorithm performance to the current Rwandan National Criteria for NG/CT diagnosis. METHODS: The risk algorithm was derived in a cohort (n = 468) comprised of symptomatic women in Kigali who sought free screening and treatment for sexually transmitted infections and vaginal dysbioses at our research site. We used logistic regression to derive a risk algorithm for prediction of NG/CT infection. Ten-fold cross-validation internally validated the risk algorithm. We applied the risk algorithm to an external validation cohort also comprised of symptomatic Rwandan women (n = 305). Measures of calibration, discrimination, and screening performance of our risk algorithm compared to the current Rwandan National Criteria are presented. RESULTS: The prevalence of NG/CT in the derivation cohort was 34.6%. The risk algorithm included: age < =25, having no/primary education, not having full-time employment, using condoms only sometimes, not reporting genital itching, testing negative for vaginal candida, and testing positive for bacterial vaginosis. The model was well calibrated (Hosmer-Lemeshow p = 0.831). Higher risk scores were significantly associated with increased prevalence of NG/CT infection (p < 0.001). Using a cut-point score of > = 5, the risk algorithm had a sensitivity of 81%, specificity of 54%, positive predictive value (PPV) of 48%, and negative predictive value (NPV) of 85%. Internal and external validation showed similar predictive ability of the risk algorithm, which outperformed the Rwandan National Criteria. Applying the Rwandan National Criteria cutoff of > = 2 (the current cutoff) to our derivation cohort had a sensitivity of 26%, specificity of 89%, PPV of 55%, and NPV of 69%. CONCLUSIONS: These data support use of a locally relevant, evidence-based risk algorithm to significantly reduce the number of untreated NG/CT cases in symptomatic Rwandan women. The risk algorithm could be a cost-effective way to target treatment to those at highest NG/CT risk. The algorithm could also aid in sexually transmitted infection risk and prevention communication between providers and clients.


Asunto(s)
Algoritmos , Infecciones por Chlamydia/diagnóstico , Chlamydia trachomatis , Gonorrea/diagnóstico , Neisseria gonorrhoeae , Adulto , Infecciones por Chlamydia/epidemiología , Infecciones por Chlamydia/microbiología , Femenino , Gonorrea/epidemiología , Gonorrea/microbiología , Humanos , Modelos Logísticos , Tamizaje Masivo , Valor Predictivo de las Pruebas , Prevalencia , Factores de Riesgo , Rwanda/epidemiología , Sensibilidad y Especificidad , Adulto Joven
17.
BMC Womens Health ; 21(1): 411, 2021 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-34911535

RESUMEN

BACKGROUND: There is unmet need for family planning in Rwanda. We previously developed an evidence-based couples' family planning counseling (C)FPC program in the capital city that combines: (1) fertility goal-based family planning counseling with a focus on long-acting reversible contraceptive (LARC) for couples wishing to delay pregnancy; (2) health center capacity building for provision of LARC methods, and (3) LARC promotion by community health workers (CHW) trained in community-based provision of oral and injectable contraception. From 2015 to 2016, this service was integrated into eight government health centers in Kigali, reaching 6072 clients and resulting in 5743 LARC insertions. METHODS: From May to July 2016, we conducted cross-sectional health center needs assessments in 30 rural health centers using surveys, key informant interviews, logbook extraction, and structured observations. The assessment focused on the infrastructure, materials, and human resources needed for LARC demand creation and provision. RESULTS: Few nurses had received training in LARC insertion [41% implant, 27% intrauterine device (IUD)]. All health centers reported working with CHW, but none trained in LARC promotion. Health centers had limited numbers of IUDs (median 10), implants (median 39), functional gynecological exam tables (median 2), and lamps for viewing the cervix (median 0). Many did not have backup power supplies (40%). Most health centers reported no funding partners for family planning assistance (60%). Per national guidelines, couples' voluntary HIV counseling and testing (CVCT) was provided at the first antenatal visit at all clinics, reaching over 80% of pregnant women and their partners. However, only 10% of health centers had integrated family planning and HIV services. CONCLUSIONS: To successfully implement (C)FPC and LARC services in rural health centers across Rwanda, material and human resource capacity for LARC provision will need to be greatly strengthened through equipment (gynecological exam tables, sterilization capacity, lamps, and backup power supplies), provider trainings and follow-up supervision, and new funding partnerships. Simultaneously, awareness of LARC methods will need to be increased among couples through education and promotion to ensure that demand and supply scale up together. The potential for integrating (C)FPC with ongoing CVCT in antenatal clinics is unique in Africa and should be pursued.


Asunto(s)
Anticonceptivos Femeninos , Anticoncepción Reversible de Larga Duración , Anticoncepción/métodos , Estudios Transversales , Servicios de Planificación Familiar , Femenino , Gobierno , Humanos , Embarazo , Rwanda
18.
J Natl Black Nurses Assoc ; 32(2): 37-41, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35338803

RESUMEN

Healthcare providers face certain barriers to fully assessing different social needs and referring patients to community resources appropriately, perpetuating healthcare disparities. The purpose of this quality improvement study was to create an intervention to increase assessment of social determinants of health (SDOH) and referrals. A module incorporating concepts of SDOH was developed and delivered during two training sessions. This module focused on: Partnership, Acceptance, Compassion, and Evocation (PACE). It was found that the public health providers at a local public health center were able to appropriately refer 55% of all new and annual patients screened with specific SDOH needs after the educational module was implemented. An overall increase in SDOH understanding and referrals was also found. SDOH training and ongoing social needs screenings could be incorporated in public health centers to decrease healthcare inequities present among minorities and individuals who live in poverty.


Asunto(s)
Equidad en Salud , Disparidades en Atención de Salud , Humanos , Salud Pública , Derivación y Consulta , Determinantes Sociales de la Salud
19.
J Clin Microbiol ; 58(9)2020 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-32522828

RESUMEN

The sexually transmitted infections (STIs) chlamydia (CT) and gonorrhea (NG) are often asymptomatic in women and undetected by syndromic management, leading to complications such as pelvic inflammatory disease, infertility, and ectopic pregnancy. Molecular testing, such as the GeneXpert CT/NG assay, is highly sensitive, but cost restraints preclude implementation of these technologies in resource-limited settings. Pooled testing is one strategy to reduce the cost per sample, but the extent of savings depends on disease prevalence. The current study describes a pooling strategy based on identification of sociodemographic and laboratory factors associated with CT/NG prevalence in a high-risk cohort of Zambian female sex workers and single mothers conducted from 2016 to 2019. Factors associated with testing positive for CT/NG via logistic regression modeling included city, younger age, lower education, long-acting reversible contraception usage, Trichomonas vaginalis infection, bacterial vaginosis, and incident syphilis infection. Based on these factors, the study population was stratified into high-, intermediate-, and low-prevalence subgroups and tested accordingly-individually, pools of 3, or pools of 4, respectively. The cost per sample was reduced from $18 to as low as $9.43 in the low-prevalence subgroup. The checklist tool and pooling approach described can be used in a variety of treatment algorithms to lower the cost per sample and increase access to molecular STI screening. This is particularly valuable in resource-limited settings to detect and treat asymptomatic CT/NG infections missed by traditional syndromic management.


Asunto(s)
Infecciones por Chlamydia , Gonorrea , Trabajadores Sexuales , Enfermedades de Transmisión Sexual , Algoritmos , Infecciones por Chlamydia/diagnóstico , Infecciones por Chlamydia/epidemiología , Chlamydia trachomatis/genética , Femenino , Gonorrea/diagnóstico , Gonorrea/epidemiología , Humanos , Neisseria gonorrhoeae/genética , Embarazo , Prevalencia
20.
Am J Obstet Gynecol ; 222(4S): S917.e1-S917.e15, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31953114

RESUMEN

BACKGROUND: Integrating family planning interventions with HIV studies in developing countries has been shown to prevent mother-to-child HIV transmission and simultaneously reduce HIV and unintended pregnancy in high-risk populations. As part of a prospective cohort study on HIV incidence and risk factors in Zambian women having unprotected sex, we also offered family planning counseling and immediate access to long-acting reversible contraceptives. Although long-acting reversible contraceptives are the most effective form of contraception, many Zambian women are limited to oral or injectable methods because of a lack of knowledge or method availability. This project offers to single mothers who are enrolled in a cohort study information about and access to long-acting reversible contraceptives at enrollment and at each follow-up visit. OBJECTIVE: This study evaluates how fertility intentions affect long-acting reversible contraceptive use in HIV-negative single mothers in Zambia. Our primary outcome was long-acting reversible contraceptive use throughout the study participation. We also estimated rates of long-acting reversible contraceptive uptake and discontinuation. We specifically studied single mothers because they are at high risk for unintended pregnancy, which can have significant negative ramifications on their financial, social, and psychologic circumstances. STUDY DESIGN: From 2012-2017, Zambia Emory HIV Research Project recruited 521 HIV-negative single mothers ages 18-45 years from government clinics in Lusaka and Ndola, Zambia's 2 largest cities. Participants were followed every 3 months for up to 5 years. At each visit, we discussed fertility goals and contraceptive options and offered a long-acting reversible method to any woman who was not pregnant or who already was using a long-acting reversible or permanent contraceptive method. Data were collected on demographic factors, sexual behavior, and reproductive history. Multivariable logistic regression was used to model baseline fertility intentions with long-acting reversible contraceptive use. RESULTS: We enrolled 518 women; 57 women did not return for any follow-up visits. There was a significant increase in long-acting reversible contraceptive use during the study. At baseline, 93 of 518 women (18%) were using a long-acting reversible method, and 151 of 461 women (33%) used a long-acting reversible method at the end of follow-up period (P<.0001). Four women chose an intrauterine device, and 91 women chose an implant for their first uptake event. After we adjusted the data for other confounders, we found that women in Ndola who did not desire any more children were more likely to use a long-acting reversible contraceptive (adjusted prevalence ratio, 2.02; 95% confidence interval, 1.88-3.42). During follow up, 37 of 183 long-acting reversible contraceptive users (20%) discontinued their method; women who desired future children at baseline were more likely to discontinue earlier (P=.016). CONCLUSION: This study demonstrates that integrated family planning services can increase long-acting reversible contraceptive use successfully among Zambian single mothers, who are a vulnerable population that disproportionately is affected by unintended pregnancy. A steady increase in use over time confirms the importance of repeated messaging about these unfamiliar methods. Thus, it is imperative that family planning interventions target single mothers in developing countries to promote effective contraceptive use.


Asunto(s)
Composición Familiar , Servicios de Planificación Familiar/organización & administración , Infecciones por VIH/prevención & control , Intención , Anticoncepción Reversible de Larga Duración/estadística & datos numéricos , Madres , Padres Solteros , Adolescente , Adulto , Atención a la Salud/organización & administración , Femenino , Humanos , Modelos Logísticos , Persona de Mediana Edad , Análisis Multivariante , Adulto Joven , Zambia
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