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1.
Clin Infect Dis ; 74(10): 1812-1820, 2022 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-34409431

RESUMO

BACKGROUND: The impact of remdesivir (RDV) on mortality rates in coronavirus disease 2019 (COVID-19) is controversial, and the mortality effect in subgroups of baseline disease severity has been incompletely explored. The purpose of this study was to assess the association of RDV with mortality rates in patients with COVID-19. METHODS: In this retrospective cohort study we compared persons receiving RDV with those receiving best supportive care (BSC). Patients hospitalized between 28 February and 28 May 2020 with laboratory-confirmed severe acute respiratory syndrome coronavirus 2 infection were included with the development of COVID-19 pneumonia on chest radiography and hypoxia requiring supplemental oxygen or oxygen saturation ≤94% with room air. The primary outcome was overall survival, assessed with time-dependent Cox proportional hazards regression and multivariable adjustment, including calendar time, baseline patient characteristics, corticosteroid use, and random effects for hospital. RESULTS: A total of 1138 patients were enrolled, including 286 who received RDV and 852 treated with BSC, 400 of whom received hydroxychloroquine. Corticosteroids were used in 20.4% of the cohort (12.6% in RDV and 23% in BSC). Comparing persons receiving RDV with those receiving BSC, the hazard ratio (95% confidence interval) for death was 0.46 (.31-.69) in the univariate model (P < .001) and 0.60 (.40-.90) in the risk-adjusted model (P = .01). In the subgroup of persons with baseline use of low-flow oxygen, the hazard ratio (95% confidence interval) for death in RDV compared with BSC was 0.63 (.39-1.00; P = .049). CONCLUSION: Treatment with RDV was associated with lower mortality rates than BSC. These findings remain the same in the subgroup with baseline use of low-flow oxygen.


Assuntos
Tratamento Farmacológico da COVID-19 , Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Humanos , Oxigênio , Estudos Retrospectivos , SARS-CoV-2
2.
Sex Transm Infect ; 96(6): 457-463, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31919275

RESUMO

OBJECTIVE: HIV infection increases the risk of high-grade cervical neoplasia and invasive cervical carcinoma. The study addresses the limited data describing human papillomavirus (HPV) infection and cervical neoplasia among HIV-infected women in HIV-discordant relationships in sub-Saharan Africa, which is needed to inform screening strategies. METHODS: A cross-sectional study of HIV-infected women with HIV-uninfected partners was conducted to determine the distribution of type-specific HPV infection and cervical cytology. This study was nested in a prospective cohort recruited between September 2007 and December 2009 in Nairobi, Kenya. Cervical cells for HPV DNA testing and conventional cervical cytology were collected. HPV types were detected and genotyped by Roche Linear Array PCR assay. RESULTS: Among 283 women, the overall HPV prevalence was 62%, and 132 (47%) had ≥1 high-risk (HR)-HPV genotype. Of 268 women with cervical cytology results, 18 (7%) had high-grade cervical lesions or more severe by cytology, of whom 16 (89%) were HR-HPV-positive compared with 82 (41%) of 199 women with normal cytology (p<0.001). The most common HR-HPV types in women with a high-grade lesion or more severe by cytology were HPV-52 (44%), HPV-31 (22%), HPV-35 (22%), HPV-51 (22%) and HPV-58 (22%). HR-HPV genotypes HPV-16 or HPV-18 were found in 17% of women with high-grade lesions or more severe. HR-HPV screening applied in this population would detect 89% of those with a high-grade lesion or more severe, while 44% of women with normal or low-grade cytology would screen positive. CONCLUSION: HR-HPV prevalence was high in this population of HIV-infected women with an uninfected partner. Choice of screening for all HR genotypes versus a subset of HR genotypes in these HIV-infected women will strongly affect the performance of an HPV screening strategy relative to cytological screening. Regional and subpopulation differences in HR-HPV genotype distributions could affect screening test performance.


Assuntos
Células Escamosas Atípicas do Colo do Útero , Carcinoma de Células Escamosas/epidemiologia , Infecções por HIV/epidemiologia , Infecções por Papillomavirus/epidemiologia , Lesões Intraepiteliais Escamosas Cervicais/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Adolescente , Adulto , Células Escamosas Atípicas do Colo do Útero/virologia , Carcinoma de Células Escamosas/virologia , Estudos Transversais , Feminino , Humanos , Quênia/epidemiologia , Pessoa de Meia-Idade , Infecções por Papillomavirus/virologia , Prevalência , Estudos Prospectivos , Parceiros Sexuais , Lesões Intraepiteliais Escamosas Cervicais/virologia , Neoplasias do Colo do Útero/virologia , Adulto Jovem
3.
J Cardiovasc Pharmacol ; 75(6): 603-607, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32168154

RESUMO

Adenoviral vectors are useful tools in manipulating a gene of interest in vitro and in vivo, including in the vascular system. The transduction efficiencies of adenoviral vectors in vascular cells such as endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) are known to be lower than those in epithelial cell types. The effective entry for adenoviral vectors is primarily mediated through the coxsackievirus and adenovirus receptor (CAR), which has been shown to be expressed in both cell types. Cationic liposomes have been used to enhance adenovirus transduction efficiency in nonepithelial cells. Accordingly, the aim of this study is to obtain new information regarding differences in transduction efficiencies, cationic liposome sensitivity, and CAR expression between ECs and VSMCs. Using cultured rat aortic ECs and VSMCs, here, we have compared transduction efficiency of adenoviruses with or without inclusion of liposomes and CAR expression. A significant increase in basal transduction efficiency was observed in ECs compared with VSMCs. Cationic liposome polybrene enhanced transduction efficiency in VSMCs, whereas decreased efficiency was observed in ECs. Western blotting demonstrated expression of the CAR in ECs but not in VSMCs. Proteomic analysis and mouse aorta immunostaining further suggests significant expression of the CAR in ECs but not in VSMCs. In conclusion, adenoviruses can effectively transduce the gene of interest in aortic ECs likely because of abundant expression of the CAR, whereas cationic liposomes such as polybrene enhance the transduction efficiency in VSMCs lacking CAR expression.


Assuntos
Adenoviridae/genética , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/metabolismo , Células Endoteliais/metabolismo , Vetores Genéticos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Transdução Genética , Proteína ADAM17/genética , Proteína ADAM17/metabolismo , Animais , Células Cultivadas , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Brometo de Hexadimetrina/química , Lipossomos , Masculino , Camundongos Endogâmicos C57BL , Ratos , Ratos Sprague-Dawley , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 1 de Angiotensina/metabolismo
4.
AIDS Behav ; 18(1): 189-93, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23728523

RESUMO

HIV-1 serodiscordant couples may experience increased risks of relationship dissolution; however, longitudinal stability of these relationships is poorly understood. We determined rates and correlates of separation among 469 serodiscordant couples in Nairobi and found that 113 (24 %) separated during 2 years of follow-up. Couples with a female HIV-1 infected partner (F+M-) and no income were more likely to separate than M+F- couples without income (HR = 5.0; 95 % CI 1.1-25.0), and F+M- and M+F- couples with income (HR = 2.4; 95 % CI 1.3-4.5 and HR = 2.3; 95 % CI 1.2-4.8, respectively). High separation rates may be important for couple support services and for conducting discordant couple studies.


Assuntos
Infecções por HIV/prevenção & controle , Heterossexualidade , Relações Interpessoais , Parceiros Sexuais/psicologia , Antirretrovirais/administração & dosagem , Características da Família , Feminino , Seguimentos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/transmissão , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Quênia , Masculino , Saúde Reprodutiva , Fatores de Risco , Comportamento Sexual
5.
J Infect Dis ; 208(7): 1093-101, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23840044

RESUMO

BACKGROUND: The synergy between herpes simplex virus type 2 (HSV-2) and human immunodeficiency virus type 1 (HIV-1) is well known, but lack of knowledge about the epidemiology of HSV-2 acquisition in HIV-1-discordant couples hampers development of HSV-2 prevention interventions that could reduce HIV-1 transmission. METHODS: HIV-1-discordant couples were enrolled in Nairobi, Kenya, and followed for up to 2 years. HSV-2 status was determined using HerpeSelect HSV-2 ELISA. Correlates of prevalence and incidence were assessed. RESULTS.: Of 469 HIV-1-discordant couples, at baseline, 353 (75.3%) were affected by HSV-2, of which 189 (53.5%) were concordantly HSV-2 seropositive and 164 (46.5%) were HSV-2-discordant. Prevalence was lowest among HIV-1-uninfected men (39.9%) compared to HIV-1-infected women (64.8%), HIV-1-infected men (66.7%), and HIV-1-uninfected women (68.5%). During follow-up, HSV-2 seroincidence was 14.9 per 100 person-years. Incidence was 1.6-fold higher among females compared to males (95% confidence interval [CI], 1.00-2.48) and 2.5-fold higher in HIV-1-infected compared to uninfected women (95% CI, 1.12-5.74). At least 30% of incident HSV-2 infections originated from an outside partner. CONCLUSIONS: The high HSV-2 prevalence and incidence in HIV-1-discordant couples in sub-Saharan Africa suggest HSV-2 treatment and prevention could be an effective targeted strategy to reduce HSV-2 and HIV-1 transmission in this high-risk population.


Assuntos
Infecções por HIV/complicações , HIV-1/isolamento & purificação , Herpes Genital/epidemiologia , Herpesvirus Humano 2/isolamento & purificação , Adulto , Ensaio de Imunoadsorção Enzimática , Características da Família , Feminino , Infecções por HIV/virologia , Herpes Genital/virologia , Humanos , Incidência , Quênia/epidemiologia , Masculino , Prevalência
6.
AIDS Care ; 25(3): 265-72, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22866934

RESUMO

Timely initiation of antiretroviral therapy (ART) is particularly important for HIV-discordant couples because viral suppression greatly reduces the risk of transmission to the uninfected partner. To identify issues and concerns related to ART initiation among HIV-discordant couples, we recruited a subset of discordant couples participating in a longitudinal study in Nairobi to participate in in-depth interviews and focus group discussions about ART. Our results suggest that partners in HIV-discordant relationships discuss starting ART, yet most are not aware that ART can decrease the risk of HIV transmission. In addition, their concerns about ART initiation include side effects, sustaining an appropriate level of drug treatment, HIV/AIDS-related stigma, medical/biological issues, psychological barriers, misconceptions about the medications, the inconvenience of being on therapy, and lack of social support. Understanding and addressing these barriers to ART initiation among discordant couples is critical to advancing the HIV "treatment as prevention" agenda.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Seleção por Sorologia para HIV , Conhecimentos, Atitudes e Prática em Saúde , Adesão à Medicação/psicologia , Adulto , Tomada de Decisões , Feminino , Grupos Focais , Infecções por HIV/psicologia , Infecções por HIV/transmissão , Humanos , Quênia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Parceiros Sexuais/psicologia , Adulto Jovem
7.
Retrovirology ; 9: 1, 2012 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-22214232

RESUMO

BACKGROUND: The GNB3 C825T polymorphism is associated with increased G protein-mediated signal transduction, SDF-1α-mediated lymphocyte chemotaxis, accelerated HIV-1 progression, and altered responses to antiretroviral therapy among Caucasian subjects. The GNB3 825T allele is highly prevalent in African populations, and as such any impact on HIV-1 acquisition or progression rates could have a dramatic impact. This study examines the association of the 825T polymorphism with HIV-1 acquisition, disease progression and immune activation in two African cohorts. GNB3 825 genotyping was performed for enrolees in both a commercial sex worker cohort and a perinatal HIV transmission (PHT) cohort in Nairobi, Kenya. Ex vivo immune activation was quantified by flow cytometry, and plasma chemokine levels were assessed by cytokine bead array. RESULTS: GNB3 genotype was not associated with sexual or vertical HIV-1 acquisition within these cohorts. Within the Pumwani cohort, GNB3 genotype did not affect HIV-1 disease progression among seroconverters or among HIV-1-positive individuals after adjustment for baseline CD4 count. Maternal CD4 decline and viral load increase in the PHT cohort did not differ between genotypes. Multi-parametric flow cytometry assessment of T cell activation (CD69, HLA-DR, CD38) and Treg frequency (CD25(+)FOXP3(+)) found no differences between genotype groups. Plasma SDF-1α, MIP-1ß and TRAIL levels quantified by cytokine bead array were also similar between groups. CONCLUSIONS: In contrast to previous reports, we were unable to provide evidence to suggest that the GNB3 C825T polymorphism affects HIV-1 acquisition or disease progression within African populations. Ex vivo immune activation and plasma chemokine levels were similarly unaffected by GNB3 genotype in both HIV-1-negative and HIV-1-positive individuals. The paucity of studies investigating the impact of GNB3 polymorphism among African populations and the lack of mechanistic studies make it difficult to assess the true biological significance of this polymorphism in HIV-1 infection.


Assuntos
Predisposição Genética para Doença , Infecções por HIV/genética , HIV-1/imunologia , HIV-1/patogenicidade , Proteínas Heterotriméricas de Ligação ao GTP/genética , Polimorfismo Genético , Estudos de Coortes , Citocinas/metabolismo , Progressão da Doença , Feminino , Humanos , Lactente , Recém-Nascido , Quênia , Gravidez
8.
J Immunol Methods ; 510: 113328, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35934070

RESUMO

Monocytes are highly versatile innate immune cells responsible for pathogen clearance, innate immune coordination, and induction of adaptive immunity. Monocytes can directly and indirectly integrate pathogen-destructive instructions and contribute to disease control via pathogen uptake, presentation, or the release of cytokines. Indirect pathogen-specific instructions are conferred via Fc-receptor signaling and triggered by antibody opsonized material. Given the tremendous variation in polyclonal humoral immunity, defining the specific antibody-responses able to arm monocytes most effectively remains incompletely understood. While monocyte cell line-based assays have been used previously, cell lines may not faithfully recapitulate the full biology of monocytes. Thus, here we describe a multifaceted antigen-specific method for probing antibody-dependent primary monocyte phagocytosis (ADMP) and secondary responses. The assay not only reliably captures phagocytic uptake of immune complexes, but also detects unique changes in surface markers and cytokine secretions profiles, poorly detected by monocytic cell lines. The assay captures divergent polyclonal-monocyte recruiting activity across subjects with varying SARS-CoV-2 disease severity and also revealed biological nuances in Fc-mutant monoclonal antibody activity related to differences in Fc-receptor binding. Thus, the ADMP assay is a flexible assay able to provide key insights into the role of humoral immunity in driving monocyte phenotypic transitions and downstream functions across many diseases.


Assuntos
COVID-19 , Monócitos , Anticorpos Monoclonais , Complexo Antígeno-Anticorpo , Antígenos , Citocinas , Humanos , Fragmentos Fc das Imunoglobulinas , Fagocitose , SARS-CoV-2
9.
Medicine (Baltimore) ; 100(45): e27663, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34766569

RESUMO

ABSTRACT: The value of chest radiography (CXR) in detection and as an outcome predictor in the management of patients with coronavirus disease-2019 (COVID-19) has not yet been fully understood.To validate a standardized CXR scoring system and assess its prognostic value in hospitalized patients found to have COVID-19 by imaging criteria and to compare it to computed tomography (CT).In this cross-sectional chart review study, patients aged 18-years or older who underwent chest CT at a single institution with an imaging-based diagnosis of COVID-19 between March 15, 2020 to April 15, 2020 were included. Each patient's CXR and coronal CT were analyzed for opacities in a 6-zonal assessment method and aggregated into a "Sextus score." Inter-reader variability and correlation between CXR and coronal CT images were investigated to validate this scoring system. Univariable and multiple logistic regression techniques were used to investigate relationships between CXR scores and clinical parameters in relation to patient outcomes.One hundred twenty-four patients (median [interquartile range] age 58.5 [47.5-69.0] years, 72 [58%] men, 58 [47%] Blacks, and 35 [28%] Hispanics) were included. The CXR Sextus score (range: 0-6) was reliable (inter-rater kappa = 0.76; 95% confidence interval [CI]: 0.69-0.83) and correlated strongly with the CT Sextus score (Spearman correlation coefficient = 0.75, P < .0001). Incremental increases of CXR Sextus scores of 2 points were found to be an independent predictor of intubation (adjusted odds ratio [95% CI]: 4.49 [1.98, 10.20], P = .0003) and prolonged hospitalization (≥10 days) (adjusted odds ratio [95% CI]: 4.06 [1.98, 8.32], P = .0001).The CXR Sextus score was found to be reproducible and CXR-CT severity scores were closely correlated. Increasing Sextus scores were associated with increased risks for intubation and prolonged hospitalization for patients with COVID-19 in a predominantly Black population. The CXR Sextus score may provide insight into identifying and monitoring high-risk patients with COVID-19.


Assuntos
COVID-19/diagnóstico por imagem , Radiografia Torácica , Idoso , COVID-19/diagnóstico , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , SARS-CoV-2 , Raios X
10.
JCI Insight ; 6(6)2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33621211

RESUMO

Comorbid medical illnesses, such as obesity and diabetes, are associated with more severe COVID-19, hospitalization, and death. However, the role of the immune system in mediating these clinical outcomes has not been determined. We used multiparameter flow cytometry and systems serology to comprehensively profile the functions of T cells and antibodies targeting spike, nucleocapsid, and envelope proteins in a convalescent cohort of COVID-19 subjects who were either hospitalized (n = 20) or not hospitalized (n = 40). To avoid confounding, subjects were matched by age, sex, ethnicity, and date of symptom onset. Surprisingly, we found that the magnitude and functional breadth of virus-specific CD4+ T cell and antibody responses were consistently higher among hospitalized subjects, particularly those with medical comorbidities. However, an integrated analysis identified more coordination between polyfunctional CD4+ T cells and antibodies targeting the S1 domain of spike among subjects who were not hospitalized. These data reveal a functionally diverse and coordinated response between T cells and antibodies targeting SARS-CoV-2, which is reduced in the presence of comorbid illnesses that are known risk factors for severe COVID-19.


Assuntos
Anticorpos Antivirais/fisiologia , Linfócitos T CD4-Positivos/fisiologia , COVID-19/virologia , Hospitalização , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus , Vírion , Adulto , Idoso , Anticorpos Neutralizantes/metabolismo , Anticorpos Neutralizantes/fisiologia , Anticorpos Antivirais/metabolismo , Linfócitos T CD4-Positivos/metabolismo , COVID-19/epidemiologia , COVID-19/imunologia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/imunologia , Comorbidade , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/imunologia , Feminino , Humanos , Imunidade Humoral , Masculino , Pessoa de Meia-Idade , Nucleocapsídeo , Índice de Gravidade de Doença , Envelope Viral , Proteínas Virais , Adulto Jovem
11.
AIDS Behav ; 14(5): 1066-71, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20544384

RESUMO

This study examines the incidence and predictors of pregnancy in HIV-1-discordant couples from Nairobi, Kenya. Women from 454 discordant couples were followed for up to 2 years. One-year cumulative incidence of pregnancy was 9.7%. Pregnancy rates did not differ significantly between HIV-1-infected and uninfected women (HR = 1.46). The majority of pregnancies occurred among women < 30 years old reporting a desire for future children (1-year incidence 22.2%). Pregnancy rates may be high among discordant couples, indicating desire for children may override concerns of HIV-1 transmission and increase unprotected sex, and highlighting the need to make conception safer.


Assuntos
Infecções por HIV/epidemiologia , Soropositividade para HIV/epidemiologia , Taxa de Gravidez , Reprodução , Adulto , Distribuição por Idade , Estudos de Coortes , Feminino , Seguimentos , Previsões , Infecções por HIV/psicologia , Infecções por HIV/transmissão , Soronegatividade para HIV , Soropositividade para HIV/psicologia , Soropositividade para HIV/transmissão , HIV-1/imunologia , Humanos , Incidência , Quênia/epidemiologia , Masculino , Gravidez , Fatores de Risco , Cônjuges/estatística & dados numéricos , Adulto Jovem
12.
Radiol Case Rep ; 15(9): 1614-1617, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32685081

RESUMO

A 59-year-old incarcerated woman who was diagnosed with invasive ductal carcinoma in 2016 was brought in for evaluation of the breast cancer. Upon evaluation of the computed tomography chest for breast cancer restaging, diffuse bilateral ground glass opacities and a reverse halo sign in the right lower lobe concerning for atypical viral pneumonia were discovered. The patient was afebrile, had an oxygen saturation of 100%, and denied chest pain as well as shortness of breath. On physical exam, she exhibited decreased breath sounds bilaterally and expiratory wheezing. She later received a COVID-19 test, which came back positive. Infection with the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, also known as COVID-19) may remain asymptomatic in the initial phase, leading to under-recognition and incidental detection on procedures for standard clinical indications. Hospitals, in particular diagnostic imaging services, should prepare accordingly in regard to health precautions while keeping in mind the potential discrepancies between clinical presentation and resultant radiologic patterns. This awareness should be heightened in patients at higher risk (ie, prisoners). Furthermore, by acting upon the incidental detection of this virus during its early stages, subsequent steps could help prevent the spread of the virus.

13.
medRxiv ; 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33269369

RESUMO

Comorbid medical illnesses, such as obesity and diabetes, are associated with more severe COVID-19, hospitalization, and death. However, the role of the immune system in mediating these clinical outcomes has not been determined. We used multi-parameter flow cytometry and systems serology to comprehensively profile the functions of T cells and antibodies targeting spike, nucleocapsid, and envelope proteins in a convalescent cohort of COVID-19 subjects who were either hospitalized (n=20) or not hospitalized (n=40). To avoid confounding, subjects were matched by age, sex, ethnicity, and date of symptom onset. Surprisingly, we found that the magnitude and functional breadth of virus-specific CD4 T cell and antibody responses were consistently higher among hospitalized subjects, particularly those with medical comorbidities. However, an integrated analysis identified more coordination between polyfunctional CD4 T-cells and antibodies targeting the S1 domain of spike among subjects that were not hospitalized. These data reveal a functionally diverse and coordinated response between T cells and antibodies targeting SARS-CoV-2 which is reduced in the presence of comorbid illnesses that are known risk factors for severe COVID-19. Our data suggest that isolated measurements of the magnitudes of spike-specific immune responses are likely insufficient to anticipate vaccine efficacy in high-risk populations.

14.
Immun Inflamm Dis ; 6(3): 392-401, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29974672

RESUMO

INTRODUCTION: Spontaneous interferon-γ (IFNγ) released detected by enzyme-linked immunospot (ELISpot) assays may be a biological phenomenon. Markers of immune activation levels were assessed as correlates of high background among individuals in Kenya. METHODS: Couples concordantly seronegative for HIV-1 were enrolled. IFN-γ ELISpot assays were conducted and negative control wells were categorized as having either high or low background (≥50 and <50 SFU/106 peripheral blood mononuclear cells [PBMC], respectively). PBMC were stained for CD4, CD8, and immune activation markers (CD38 and HLA-DR) and analyzed using flow cytometry. Proportions of activated T-cells were compared between those with low and high background by Mann-Whitney U test. Correlates of background SFU and immune activation were assessed using regression models. RESULTS: Among 58 individuals, 14 (24%) had high background. Frequencies of CD4+ CD38+ HLA-DR+ and CD8+ CD38+ HLA-DR+ cells were higher in individuals with high background compared to those with low background (P = 0.02). Higher background SFU was associated with history of sexually transmitted infections (P = 0.03), and illness in the past 3 months (P = 0.005), in addition to increased levels of activated CD4+ and CD8+ cells (P range = 0.008-0.03). Female gender and male circumcision decreased levels of CD4+ and CD8+ immune activation (P range = 0.002-0.03). Additionally, higher background SFU and activated CD4+ and CD8+ cells were individually associated with positive ELISpot responses to HIV-1 peptide pools (P range = 0.01-0.03). CONCLUSIONS: These findings suggest that increased basal immune responses may be a biological mechanism contributing to higher background ELISpot SFU. Systematic exclusion of data from individuals with increased background in IFN-γ release assays may bias results in population-based studies.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Soronegatividade para HIV/imunologia , HIV-1 , Interferon gama/imunologia , ADP-Ribosil Ciclase 1/imunologia , Adulto , Cidades , ELISPOT , Feminino , Antígenos HLA-DR/imunologia , Humanos , Quênia , Ativação Linfocitária , Masculino , Glicoproteínas de Membrana/imunologia , Adulto Jovem
15.
Chem Sci ; 6(4): 2444-2448, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29308156

RESUMO

The synthesis of six trinuclear Pn3L2 macrobicycles (Pn = As, Sb) was achieved by self-assembly of a pnictogen trichloride and a 2,4,6-trisubstituted-1,3,5-benzenetrimethanethiol ligand. 1H-NMR spectroscopy reveals self-assembly in 1,1,2,2-tetrachloroethane is dynamic in solution producing two structural isomers. The symmetric and the asymmetric isomers (in which a single chloride ligand is cast in an opposing direction from other chlorides) of the As3L2 complexes exist in a ca. 2 : 1 distribution, whereas only the symmetric isomer is observed in solution for Sb3L2. Solvent effects appear to influence conformational isomerism and conversion to the final products. Macrobicycles were confirmed by 1H-NMR spectroscopy and X-ray crystallography and further studied by MP2/LANL2DZ optimizations.

16.
J Acquir Immune Defic Syndr ; 69(1): 1-10, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25622059

RESUMO

OBJECTIVE: The effects of sex hormones on the immune defenses of the female genital mucosa and its susceptibility to infections are poorly understood. The injectable hormonal contraceptive depot medroxyprogesterone acetate (DMPA) may increase the risk for HIV-1 acquisition. We assessed the local concentration in the female genital mucosa of cationic polypeptides with reported antiviral activity in relation to DMPA use. METHODS: HIV-1-uninfected women were recruited from among couples testing for HIV in Nairobi, Kenya. Cervicovaginal secretion samples were collected, and the concentrations of HNP1-3, LL-37, lactoferrin, HBD-2, and SLPI were measured by enzyme-linked immunosorbent assays. Levels of cationic polypeptides in cervicovaginal secretions were compared between women who were not using hormonal contraception and those using DMPA, oral, or implantable contraception. RESULTS: Among 228 women, 165 (72%) reported not using hormonal contraception at enrollment, 41 (18%) used DMPA, 16 (7%) used an oral contraceptive, and 6 (3%) used a contraceptive implant. Compared with nonusers of hormonal contraception, DMPA users had significantly higher mean levels of HNP1-3 (2.38 vs. 2.04 log10 ng/mL; P = 0.024), LL-37 (0.81 vs. 0.40 log10 ng/mL; P = 0.027), and lactoferrin (3.03 vs. 2.60 log10 ng/mL; P = 0.002), whereas SLPI and HBD-2 were similar. CONCLUSIONS: Although all analyzed cationic polypeptides have intrinsic antiviral capacity, their interaction and cumulative effect on female genital mucosa susceptibility to infections in vivo has yet to be unraveled. This study suggests a potential mechanism underlying the effect of DMPA on the innate immune defenses, providing a rationale to investigate its effect on HIV-1 acquisition risk.


Assuntos
Peptídeos Catiônicos Antimicrobianos/análise , Secreções Corporais/química , Colo do Útero/imunologia , Preparações de Ação Retardada/administração & dosagem , Fatores Imunológicos/administração & dosagem , Acetato de Medroxiprogesterona/administração & dosagem , Vagina/imunologia , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Quênia , Masculino
17.
Int J STD AIDS ; 25(5): 315-24, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24047885

RESUMO

Individual and sexual partner characteristics may increase the risk of abnormal cervical cytology among women in human immunodeficiency virus (HIV)-discordant relationships. Papanicolaou smears were obtained in a prospective cohort of Kenyan HIV-discordant couples. Of 441 women, 283 (64%) were HIV-infected and 158 (36%) were HIV-uninfected with HIV-infected partners. Overall, 79 (18%) had low-grade and 25 (6%) high-grade cervical abnormalities. Male herpes simplex virus type 2 (HSV-2) seropositivity and lower couple socioeconomic status were associated with cervical abnormalities (p < 0.05). HIV-uninfected women with HIV-infected male sex partners (CD4 > 350 cells/µL) had the lowest prevalence of high-grade cervical lesions. HIV-infected women (CD4 > 350 cells/µL) and HIV-uninfected women with HIV-infected partners (CD4 ≤ 350 cells/µL) were at similar intermediate risk (p > 0.05), and HIV-infected women (CD4 ≤ 350 cells/µL) had significantly higher risk of high-grade cervical abnormalities (p = 0.05). Women in HIV-discordant relationships have high rates of cervical lesions and this may be influenced by couple-level factors, including HIV status and CD4 count of the infected partner.


Assuntos
Soropositividade para HIV/complicações , Soropositividade para HIV/transmissão , Infecções por Papillomavirus/epidemiologia , Parceiros Sexuais , Displasia do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Adulto , Contagem de Linfócito CD4 , Feminino , Soropositividade para HIV/epidemiologia , HIV-1 , Humanos , Quênia/epidemiologia , Masculino , Pessoa de Meia-Idade , Papillomaviridae , Infecções por Papillomavirus/complicações , Prevalência , Estudos Prospectivos , Fatores de Risco , Fatores Socioeconômicos , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Esfregaço Vaginal , Adulto Jovem , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/virologia
18.
AIDS Res Hum Retroviruses ; 28(6): 566-70, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21902583

RESUMO

The C868T single nucleotide polymorphism in the CD4 receptor encodes an amino acid substitution of tryptophan for arginine in the third domain. Previous studies suggest that C868T increases the risk of HIV-1 acquisition; however, the influence of this single nucleotide polymorphism (SNP) on disease progression has not been established. The presence of the C868T polymorphism was not statistically significantly associated with HIV-1 disease progression outcomes in a cohort of postpartum Kenyan women.


Assuntos
Antígenos CD4/genética , Infecções por HIV/genética , HIV-1/genética , Polimorfismo de Nucleotídeo Único , Período Pós-Parto/genética , Adulto , Arginina , Contagem de Linfócito CD4 , Estudos de Coortes , Progressão da Doença , Feminino , Genótipo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Recém-Nascido , Quênia/epidemiologia , Gravidez , Triptofano , Carga Viral , Zidovudina/uso terapêutico
19.
PLoS One ; 7(2): e31996, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22389677

RESUMO

BACKGROUND: HIV exposed seronegative (HESN) women represent the population most in need of a prophylactic antiviral strategy. Mucosal cationic polypeptides can potentially be regulated for this purpose and we here aimed to determine their endogenous expression and HIV neutralizing activity in genital secretions of women at risk of HIV infection. METHODOLOGY/PRINCIPAL FINDINGS: Cervicovaginal secretions (CVS) of Kenyan women in HIV-serodiscordant relationships (HESN, n = 164; HIV seropositive, n = 60) and low-risk controls (n = 72) were assessed for the cationic polypeptides HNP1-3, LL-37 and SLPI by ELISA and for HIV neutralizing activity by a PBMC-based assay using an HIV primary isolate. Median levels of HNP1-3 and LL-37 in CVS were similar across study groups. Neither HSV-2 serostatus, nor presence of bacterial vaginosis, correlated with levels of HNP1-3 or LL-37 in the HESN women. However, an association with their partner's viral load was observed. High viral load (>10,000 HIV RNA copies/ml plasma) correlated with higher levels of HNP1-3 and LL-37 (p = 0.04 and 0.03, respectively). SLPI was most abundant in the low-risk group and did not correlate with male partner's viral load in the HESN women. HIV neutralizing activity was found in CVS of all study groups. In experimental studies, selective depletion of cationic polypeptides from CVS rendered the remaining CVS fraction non-neutralizing, whereas the cationic polypeptide fraction retained the activity. Furthermore, recombinant HNP1-3 and LL-37 could induce neutralizing activity when added to CVS lacking intrinsic activity. CONCLUSIONS/SIGNIFICANCE: These findings show that CVS from HESN, low-risk, and HIV seropositive women contain HIV neutralizing activity. Although several innate immune proteins, including HNP1-3 and LL-37, contribute to this activity these molecules can also have inflammatory properties. This balance is influenced by hormonal and environmental factors and in the present HIV serodiscordant couple cohort study we show that a partner's viral load is associated with levels of such molecules.


Assuntos
Muco do Colo Uterino/química , Infecções por HIV/imunologia , HIV/efeitos dos fármacos , Peptídeos/imunologia , Peptídeos/metabolismo , Vagina/metabolismo , Muco do Colo Uterino/imunologia , Feminino , Soropositividade para HIV , Humanos , Masculino , Estudos Prospectivos , Vagina/imunologia
20.
PLoS One ; 7(8): e43138, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22937017

RESUMO

BACKGROUND: Longitudinal studies of HIV-1-infected individuals or those at risk of infection are subject to missed study visits that may have negative consequences on the care of participants and can jeopardize study validity due to bias and loss of statistical power. Distance between participant residence and study clinic, as well as other socioeconomic and demographic factors, may contribute to interruptions in patient follow-up. METHODS: HIV-1-serodiscordant couples were enrolled between May 2007 and October 2009 and followed for two years in Nairobi, Kenya. At baseline, demographic and home location information was collected and linear distance from each participant's home to the study clinic was determined. Participants were asked to return to the study clinic for quarterly visits, with follow-up interruptions (FUI) defined as missing two consecutive visits. Cox proportional hazards regression was used to assess crude and adjusted associations between FUI and home-to-clinic distance, and other baseline characteristics. RESULTS: Of 469 enrolled couples, 64% had a female HIV-1-infected partner. Overall incidence of FUI was 13.4 per 100 person-years (PY), with lower incidence of FUI in HIV-1-infected (10.8 per 100 PY) versus -uninfected individuals (16.1 per 100 PY) (hazard ratio [HR] = 0.66; 95% confidence interval [CI]: 0.50, 0.88). Among HIV-1-infected participants, those living between 5 and 10 kilometers (km) from the study clinic had a two-fold increased rate of FUI compared to those living <5 km away (HR = 2.17; 95% CI: 1.09, 4.34). Other factors associated with FUI included paying higher rent (HR = 1.67; 95% CI: 1.05, 2.65), having at least primary school education (HR = 1.96; 95% CI: 1.02, 3.70), and increased HIV-1 viral load (HR = 1.23 per log(10) increase; 95% CI: 1.01, 1.51). CONCLUSIONS: Home-to-clinic distance, indicators of socioeconomic status, and markers of disease progression may affect compliance with study follow-up schedules. Retention strategies should focus on participants at greatest risk of FUI to ensure study validity.


Assuntos
Características da Família , Infecções por HIV , Cooperação do Paciente/estatística & dados numéricos , Adulto , Feminino , Humanos , Incidência , Quênia , Masculino , Estudos Prospectivos , Classe Social
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