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1.
BMC Pregnancy Childbirth ; 19(1): 482, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31815612

RESUMO

BACKGROUND: Early antiretroviral therapy (ART) during pregnancy has dramatically reduced the risk of perinatal HIV transmission. However, studies have shown an association between premature delivery and the use of ART during pregnancy (particularly protease inhibitor (PI)-based therapies), which could be explained by placental dysfunction. The objective of this study was to evaluate the association of ART (class, duration of exposure and time of initiation) with placental function by using angiogenic factors placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) as biomarkers. METHODS: Clinical and biological data from 159 pregnant women living with HIV were analyzed. Levels of each biomarker were measured in the first and second trimester of pregnancy. After logarithmic transformation, we compared these using generalized estimating equations according to (a) the type of ART; (b) the duration of exposure to ART; and (c) the time of initiation of ART. RESULTS: After adjusting for variables such as ethnicity, maternal age, gestational age, body mass index, parity, smoking status, and sex of the fetus, we found no significant association between the class of ART (PI-based or not) and serum concentrations of PlGF or sFlt-1. Furthermore, no significant association was found between biomarker levels and the duration of ART exposure or the timing of ART initiation (pre- or post-conception). CONCLUSIONS: This study suggests that first and second trimester angiogenic factor levels are not significantly associated with ART, regardless of the duration or type (with or without PI). These observations seem reassuring when considering the use of ART during early pregnancy.


Assuntos
Antirretrovirais/efeitos adversos , Infecções por HIV/tratamento farmacológico , Fator de Crescimento Placentário/sangue , Complicações Infecciosas na Gravidez/sangue , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue , Adulto , Biomarcadores/sangue , Estudos de Coortes , Feminino , Infecções por HIV/transmissão , Humanos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/virologia , Trimestres da Gravidez/sangue , Nascimento Prematuro/induzido quimicamente
2.
Pediatr Infect Dis J ; 37(6): 595-597, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29278613

RESUMO

We evaluated quadrivalent human papillomavirus vaccine seroresponses among 35 girls living with HIV (9-13 years of ages) and compared with data on girls without HIV, as part of a subgroup analysis. The quadrivalent human papillomavirus vaccine was safe and well tolerated. However, antibody response was significantly lower in girls living with HIV relative to girls without HIV. HIV virologic suppression predicted better antibody response.


Assuntos
Infecções por HIV/virologia , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/imunologia , Imunogenicidade da Vacina , Infecções por Papillomavirus/prevenção & controle , Adolescente , Anticorpos Antivirais/sangue , Contagem de Linfócito CD4 , Canadá , Criança , Feminino , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/efeitos adversos , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/uso terapêutico , Humanos , Estudos Longitudinais , Estudos Prospectivos
3.
J Virol ; 91(23)2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-28931691

RESUMO

Hepatitis C virus (HCV) can be transmitted from mother to child during pregnancy and childbirth. However, the timing and precise biological mechanisms that are involved in this process are incompletely understood, as are the determinants that influence transmission of particular HCV variants. Here we report results of a longitudinal assessment of HCV quasispecies diversity and composition in 5 cases of vertical HCV transmission, including 3 women coinfected with human immunodeficiency virus type 1 (HIV-1). The population structure of HCV variant spectra based on E2 envelope gene sequences (nucleotide positions 1491 to 1787), including hypervariable regions 1 and 2, was characterized using next-generation sequencing and median-joining network analysis. Compatible with a loose transmission bottleneck, larger numbers of shared HCV variants were observed in the presence of maternal coinfection. Coalescent Bayesian Markov chain Monte Carlo simulations revealed median times of transmission between 24.9 weeks and 36.1 weeks of gestation, with some confidence intervals ranging into the 1st trimester, considerably earlier than previously thought. Using recombinant autologous HCV pseudoparticles, differences were uncovered in HCV-specific antibody responses between coinfected mothers and mothers infected with HCV alone, in whom generalized absence of neutralization was observed. Finally, shifts in HCV quasispecies composition were seen in children around 1 year of age, compatible with the disappearance of passively transferred maternal immunoglobulins and/or the development of HCV-specific humoral immunity. Taken together, these results provide insights into the timing, dynamics, and biologic mechanisms involved in vertical HCV transmission and inform preventative strategies.IMPORTANCE Although it is well established that hepatitis C virus (HCV) can be transmitted from mother to child, the manner and the moment at which transmission operates have been the subject of conjecture. By carrying out a detailed examination of viral sequences, we showed that transmission could take place comparatively early in pregnancy. In addition, we showed that when the mother also carried human immunodeficiency virus type 1 (HIV-1), many more HCV variants were shared between her and her child, suggesting that the mechanism and/or the route of transmission of HCV differed in the presence of coinfection with HIV-1. These results could explain why cesarean section is ineffective in preventing vertical HCV transmission and guide the development of interventions to avert pediatric HCV infection.


Assuntos
Hepacivirus/genética , Hepatite C/transmissão , Transmissão Vertical de Doenças Infecciosas , Adulto , Teorema de Bayes , Coinfecção/virologia , Biologia Computacional , Feminino , Variação Genética , Infecções por HIV/complicações , Infecções por HIV/virologia , Soropositividade para HIV , HIV-1/genética , HIV-1/imunologia , Hepacivirus/fisiologia , Hepatite C/complicações , Hepatite C/imunologia , Hepatite C/virologia , Anticorpos Anti-Hepatite C/sangue , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imunidade Humoral , Lactente , Gravidez , Complicações Infecciosas na Gravidez/virologia , Quase-Espécies , Fatores de Risco , Proteínas do Envelope Viral/genética
4.
Vaccine ; 34(40): 4799-806, 2016 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-27544584

RESUMO

OBJECTIVE: To evaluate the immunogenicity and safety of the quadrivalent HPV (qHPV) vaccine in HIV-positive women over 24months. DESIGN: Between November 2008 and December 2012, 372 women aged 15 and older were enrolled from 14 Canadian HIV outpatient clinics in an open label cohort study. The qHPV vaccine (0.5mL) was administered intramuscularly at months 0, 2 and 6. The primary study endpoint was seroconversion to any of the HPV types targeted by the qHPV vaccine. Antibody levels were measured at 0, 2, 7, 12, 18, and 24months. Adverse events were recorded throughout. RESULTS: Of 372 participants enrolled, 310 (83%) received at least one dose of the qHPV vaccine and 277 (74%) received all three doses. Ninety-five percent (293/308) were seronegative for at least one vaccine type at baseline. The median age was 38years (IQR 32-45, range 15-66), 36% were white, 44% black and 13% were of Indigenous origin. Seventy-two percent of participants had a suppressed HIV viral load (VL<40c/ml) at baseline, with a median CD4 count of 510cells/mm(3) (376-695). Month 7 HPV type-specific seroconversion rates were 99.0%, 98.7%, 98.1% and 93.6% for HPV types 6, 11, 16 and 18 respectively in the per-protocol population. Participants with suppressed HIV VL at first vaccine had a 1.74-3.05fold higher peak antibody response compared to those without (p from 0.006 to <0.0001). CONCLUSIONS: This study is the first to examine the qHPV vaccine in HIV-positive women out to 24months and the first to include HIV-positive women through to age 66. The qHPV vaccine was well tolerated, and highly immunogenic. As women with suppressed viral load had higher antibody responses, planning HPV vaccination to occur when persons are virologically suppressed would be optimal for maximizing immune response. Findings provide strong evidence that older HIV-positive women can still benefit from HPV vaccination. CLINICAL TRIAL REGISTRATION: http://www.isrctn.com/ISRCTN33674451.


Assuntos
Anticorpos Antivirais/sangue , Infecções por HIV/imunologia , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/uso terapêutico , Infecções por Papillomavirus/prevenção & controle , Carga Viral , Adolescente , Adulto , Formação de Anticorpos , Contagem de Linfócito CD4 , Canadá , Feminino , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/administração & dosagem , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Estudos Prospectivos , Soroconversão , Adulto Jovem
5.
J Acquir Immune Defic Syndr ; 60(5): 495-502, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22580562

RESUMO

OBJECTIVES: HIV disease can lead to accelerated telomere attrition, although certain drugs used as part of antiretroviral therapy (ART) can inhibit telomerase reverse transcriptase activity. This could in turn lead to shorter telomeres. We hypothesized that HIV and ART exposure would be associated with shorter leukocyte telomere length (TL) in exposed mother/infant pairs compared with controls. METHODS: In these retrospective and prospective observational cohort studies, TL was evaluated in peripheral blood leukocytes obtained from HIV-infected pregnant women treated with ART and their uninfected infants, and compared with HIV untreated (retrospective cohort) or HIV mothers and their infants (prospective cohort). RESULTS: In HIV-infected ART-exposed mothers, leukocyte TL was not significantly shorter than that in HIV untreated mothers or HIV controls, nor was their infants' TL significantly different. Cord blood of ART-exposed infants exhibited TL shorter than that from infants born to HIV-negative mothers. Placenta also showed evidence of shorter TL after adjustment for relevant covariates. Factors associated with shorter maternal and infant TL included smoking and the use of drugs of addiction in pregnancy. CONCLUSIONS: These results suggest that maternal HIV infection or exposure to ART has minimal effect on infant leukocyte TL, a reassuring finding. In contrast, tissues that express higher telomerase activity such as umbilical cord blood and placenta appear comparatively more affected by ART. Smoking and the use of drugs of addiction have a negative impact on maternal and infant leukocyte TL, possibly through oxidative telomere damage.


Assuntos
Antirretrovirais/efeitos adversos , Infecções por HIV/tratamento farmacológico , Leucócitos/efeitos dos fármacos , Complicações Infecciosas na Gravidez/tratamento farmacológico , Telômero/efeitos dos fármacos , Adolescente , Adulto , Antirretrovirais/administração & dosagem , Feminino , Infecções por HIV/imunologia , Humanos , Lactente , Recém-Nascido , Leucócitos/fisiologia , Masculino , Gravidez , Complicações Infecciosas na Gravidez/imunologia , Estudos Retrospectivos , Telomerase/antagonistas & inibidores , Adulto Jovem
6.
Virology ; 352(2): 357-67, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16781757

RESUMO

A large share of hepatitis C virus amino acid sequence variation is concentrated within two hypervariable regions located at the N-terminus of the E2 envelope glycoprotein (HVR1 and HVR2). Interhost and intrahost comparison of 391 E2 sequences derived from 17 subjects infected with HCV using amino acid entropy revealed clustering of amino acid variability at a third site (residues 431-466), which was termed HVR3. Genetic distance analysis supported the division of HVR3 into three subdomains (HVR3a, HVR3b, and HVR3c). Study of synonymous and nonsynonymous nucleic acid substitutions confirmed that HVR3a was subjected to strong intrahost-selective pressure. Physicochemical and antigenicity predictions, conservation of key residues, and molecular modeling were concordant with one another and further validated the proposed organization of HVR3. Taken together, these results are suggestive of a role for HVR3 in cell surface receptor binding and viral entry akin to that proposed for HVR1 and HVR2.


Assuntos
Genes Virais , Variação Genética , Hepacivirus/genética , Proteínas do Envelope Viral/genética , Sequência de Bases , Fenômenos Químicos , Físico-Química , DNA Viral/genética , Feminino , Infecções por HIV/complicações , HIV-1 , Hepacivirus/classificação , Hepacivirus/isolamento & purificação , Hepatite C/complicações , Hepatite C/virologia , Antígenos da Hepatite C/química , Antígenos da Hepatite C/genética , Humanos , Modelos Moleculares , Gravidez , Complicações Infecciosas na Gravidez/virologia , Conformação Proteica , Seleção Genética , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/imunologia
7.
Emerg Infect Dis ; 11(8): 1230-4, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16102312

RESUMO

We studied HIV genetic diversity in a cohort of 127 pregnant, HIV-infected women who received prenatal care at Sainte-Justine Hospital in Montreal, Canada, between 1999 and 2003. Clade assignments were derived by phylogenetic analysis of amplified pol sequences. Genotyping was successful in 103 of 127 women, 59 (57.3%) of whom were infected with clade B HIV-1, and 44 (42.7%) with nonclade B viruses, including subtypes A, C, D, F, G, and H. Four sequences remained unassigned. Forty-three of 44 women infected with non-clade B viruses were newcomers from sub-Saharan Africa, and subtype identity was consistent with those circulating in their countries of origin. These results highlight the epidemiologic importance of non-B HIV-1 in antenatal populations in a large North American urban center, underscore the influence of population movements on clade intermixing, and identify a group of patients who could be targeted for surveillance and drug therapy followup.


Assuntos
Infecções por HIV/virologia , HIV-1/genética , Complicações Infecciosas na Gravidez/virologia , Adulto , África Subsaariana/etnologia , Ásia/etnologia , Canadá/epidemiologia , Região do Caribe/etnologia , Análise por Conglomerados , Estudos de Coortes , Feminino , Produtos do Gene pol/química , Produtos do Gene pol/genética , Variação Genética , Infecções por HIV/epidemiologia , Infecções por HIV/patologia , HIV-1/classificação , Humanos , Filogenia , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , RNA Viral/sangue , RNA Viral/química , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , População Urbana , Carga Viral , Produtos do Gene pol do Vírus da Imunodeficiência Humana
9.
AIDS ; 19(8): 775-84, 2005 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-15867491

RESUMO

BACKGROUND: Hepatitis C virus (HCV) F protein is encoded in an alternate reading frame overlapping the core protein region. Its precise sequence, biological function and mode of expression are currently unclear. This study was conducted to examine the prevalence and characteristics of host humoral and cell-mediated immune responses directed against F protein in patients co-infected with HCV and HIV-1. METHODS: Mutations were introduced to allow the expression of HCV-1a F protein in the absence of core. This recombinant and a truncated form lacking the first 11 amino acid residues shared with core were expressed in Escherichia coli, and their amino acid sequences were verified by mass spectrometry. Vaccinia-F protein recombinants were used to test F protein-specific cytotoxic T lymphocyte (CTL) activity. The binding of F protein-derived peptides to HLA-A*0201 was studied to identify putative CTL epitopes. RESULTS: Sera from 23 of 39 patients infected with various HCV genotypes recognized the truncated form, including 13 of 25 subjects co-infected with HIV-1, indicative of antigenic crossreactivity and consistent with the conservation of F protein coding sequences between HCV genotypes. Crossreactive F protein-specific CTL precursors were detected in nine of 11 HCV-infected subjects, including seven of nine patients co-infected with HCV and HIV-1. Finally, three novel putative HLA-A*0201-restricted CTL epitopes were identified. CONCLUSION: These results indicate that patients co-infected with HCV and HIV-1 can mount immunoglobulin and CTL responses directed against HCV F protein that are fully comparable in scope and magnitude with those observed in individuals infected with HCV alone.


Assuntos
Infecções por HIV/imunologia , HIV-1/imunologia , Hepacivirus/imunologia , Hepatite C Crônica/imunologia , Linfócitos T Citotóxicos/imunologia , Proteínas do Core Viral/imunologia , Adulto , Reações Cruzadas , Citotoxicidade Imunológica , Epitopos/imunologia , Feminino , Genótipo , Infecções por HIV/virologia , Antígenos HLA-A , Hepacivirus/genética , Anticorpos Anti-Hepatite C/imunologia , Hepatite C Crônica/virologia , Humanos , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Vacínia/imunologia , Proteínas Virais/imunologia
10.
J Clin Microbiol ; 40(3): 902-7, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11880413

RESUMO

The novel PGMY L1 consensus primer pair is more sensitive than the MY09 and MY11 primer mix for detection and typing with PCR of human papillomavirus (HPV) DNA in genital specimens. We assessed the diagnostic yield of PGMY primers for the detection and typing of HPV by comparing the results obtained with PGMY09/PGMY11 and MY09/MY11/HMB01 on 299 genital samples. Amplicons generated with PGMY primers were typed with the line blot assay (PGMY-line blot), while HPV amplicons obtained with the degenerate primer pool MY09/MY11/HMB01 were detected with type-specific radiolabeled probes in a dot blot assay (standard consensus PCR test). Cervicovaginal lavage samples (N = 272) and cervical scrape samples (N = 27) were tested in parallel with both PCR tests. The PGMY-line blot test detected the presence of HPV DNA more frequently than the standard consensus PCR assay. The concordance for HPV typing between the two assays was 84.3% (214 of 255 samples), for a good kappa value of 0.69. Of the 177 samples containing HPV DNA by at least one method, 40 samples contained at least one HPV type detected only with PGMY-line blot, whereas positivity exclusively with the standard consensus PCR test was found for only 7 samples (P < 0.001). HPV types 45 and 52 were especially more frequently detected with PGMY than MY primers. However, most HPV types were better amplified with PGMY primers, including HPV-16. Samples with discordant results between the two PCR assays more frequently contained multiple HPV types. Studies using PGMY instead of MY primers have the potential to report higher detection rates of HPV infection not only for newer HPV types but also for well-known genital types.


Assuntos
Colo do Útero/virologia , DNA Viral/análise , Papillomaviridae/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Vagina/virologia , Feminino , Genótipo , Células HeLa , Humanos , Papillomaviridae/genética
11.
Mem. Inst. Oswaldo Cruz ; 91(3): 351-358, May-Jun. 1996.
Artigo em Inglês | LILACS | ID: lil-319863

RESUMO

The collection of dried blood spots (DBS) on filter paper provides a powerful approach for the development of large-scale, population-based screening programs. DBS methods are particularly valuable in developing countries and isolated rural regions where resources are limited. Large numbers of field specimens can be economically collected and shipped to centralized reference laboratories for genetic and (or) serological analysis. Alternatively, the dried blood can be stored and used as an archival resource to rapidly establish the frequency and distribution of newly recognized mutations, confirm patient identity or track the origins and emergence of newly identified pathogens. In this report, we describe how PCR-based technologies are beginning to interface with international screening programmes for the diagnosis and genetic characterization of human immunodeficiency virus type 1 (HIV-1). In particular, we review recent progress using DBS specimens to resolve the HIV-1 infection status of neonates, monitor the genetic evolution of HIV-1 during early infancy and establish a sentinel surveillance system for the systematic monitoring of HIV-1 genetic variation in Asia.


Assuntos
Humanos , Lactente , Recém-Nascido , Coleta de Amostras Sanguíneas , Filtração/métodos , HIV-1 , Papel , Síndrome da Imunodeficiência Adquirida/diagnóstico , Sorodiagnóstico da AIDS/métodos , Vacinas contra a AIDS , Sequência de Aminoácidos , Sequência de Bases , Primers do DNA , Variação Genética , Mutação , Reação em Cadeia da Polimerase , Resistência a Medicamentos , Análise de Sequência , Síndrome da Imunodeficiência Adquirida/transmissão , Zidovudina
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