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1.
Sci Rep ; 14(1): 10742, 2024 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730249

RESUMEN

The selection pressure imposed by the host immune system impacts on hepatitis B virus (HBV) variability. This study evaluates HBV genetic diversity, nucleos(t)ide analogs resistance and HBsAg escape mutations in HBV patients under distinct selective pressures. One hundred and thirteen individuals in different phases of HBV infection were included: 13 HBeAg-positive chronic infection, 9 HBeAg-positive chronic hepatitis, 47 HBeAg-negative chronic infection (ENI), 29 HBeAg-negative chronic hepatitis (ENH) and 15 acute infected individuals. Samples were PCR amplified, sequenced and genetically analyzed for the overlapping POL/S genes. Most HBV carriers presented genotype A (84/113; 74.3%), subgenotype A1 (67/84; 79.7%), irrespective of group, followed by genotypes D (20/113; 17.7%), F (8/113; 7.1%) and E (1/113; 0.9%). Clinically relevant mutations in polymerase (tL180M/M204V) and in the Major Hydrophilic Region of HBsAg (sY100C, T118A/M, sM133T, sD144A and sG145R) were observed. Our findings, however, indicated that most polymorphic sites were located in the cytosolic loops (CYL1-2) and transmembrane domain 4 (TMD4) of HBsAg. Lower viral loads and higher HBV genetic diversity were observed in ENI and ENH groups (p < 0.001), suggesting that these groups are subjected to a higher selective pressure. Our results provide information on the molecular characteristics of HBV in a diverse clinical setting, and may guide future studies on the balance of HBV quasispecies at different stages of infection.


Asunto(s)
Variación Genética , Genotipo , Antígenos de Superficie de la Hepatitis B , Virus de la Hepatitis B , Hepatitis B Crónica , Humanos , Virus de la Hepatitis B/genética , Hepatitis B Crónica/virología , Hepatitis B Crónica/genética , Brasil/epidemiología , Masculino , Adulto , Femenino , Persona de Mediana Edad , Antígenos de Superficie de la Hepatitis B/genética , Mutación , Farmacorresistencia Viral/genética , ADN Viral/genética , Adulto Joven , Filogenia , Antígenos e de la Hepatitis B/genética
2.
Rev. epidemiol. controle infecç ; 12(2): 87-90, abr.-jun. 2022. ilus
Artículo en Inglés | LILACS | ID: biblio-1417862

RESUMEN

Background and objectives: For decades, dengue outbreaks have been affecting vast territories of the Americas. In 2010's decade, Chikungunya and Zika virus (CHIKV and ZIKV) emerged as new arboviruses in the region. While several seroprevalence rates have been reported for dengue virus (DENV) infection in Brazil, serological surveys for the latest are scarce. We aimed to evaluate the seroprevalence of CHIKV, ZIKV, and DENV infections in pregnant women at admission to a public maternity hospital of Nova Iguaçu, state of Rio de Janeiro. Methods: A simple questionnaire was applied, containing limited demographic, obstetric, and clinical data, alongside with blood collection. Different commercial test kits, based on enzyme-linked immunosorbent assay (ELISA), were used. Results: Among 349 pregnant women enrolled from July to December 2017, there was a 28.4% seroreactivity for CHIKV, 47.2% for ZIKV, and 88.8% for DENV. Conclusion: These findings reflect the high dengue endemicity scenario and suggest a significant reach of the recent outbreaks of ZIKV and CHIKV infections in the region.(AU)


Justificativas e objetivos: Há décadas, surtos de dengue afetam vastos territórios das Américas. Na década de 2010, os vírus Chikungunya e Zika (CHIKV e ZIKV) surgiram como arbovírus emergentes na região. Embora diversas taxas de soroprevalência tenham sido relatadas para a infecção pelo vírus da dengue (DENV) no Brasil, pesquisas sorológicas para chikungunya e zika são escassas. Objetivou-se avaliar a soroprevalência das infecções por CHIKV, ZIKV e DENV em gestantes admitidas em uma maternidade pública de Nova Iguaçu, estado do Rio de Janeiro. Métodos: Foi aplicado um questionário simples, contendo dados demográficos, obstétricos e clínicos limitados, sendo realizada coleta de sangue na mesma visita. Diferentes kits de teste comerciais, baseados em ensaio imunoenzimático (ELISA), foram utilizados. Resultados: De 349 gestantes recrutadas de julho a dezembro de 2017, houve sororreatividade de 28,4% para CHIKV, 47,2% para ZIKV e 88,8% para DENV. Conclusão: Esses achados refletem o cenário de alta endemicidade da dengue e sugerem um alcance significativo dos surtos recentes causados por ZIKV e CHIKV na região.(AU)


Justificación y objetivos: Durante décadas, los brotes de dengue han afectado a vastos territorios de las Américas. En la década de 2010, los virus Chikungunya y Zika (CHIKV y ZIKV) surgieron como arbovirus emergentes en la región. Aunque se han reportadas varias tasas de seroprevalencia para la infección por el virus del dengue (DENV) en Brasil, la investigación serológica para el chikungunya y el Zika es escasa. Este estudio tuvo como objetivo evaluar la seroprevalencia de infecciones por CHIKV, ZIKV y DENV en mujeres embarazadas ingresadas en una maternidad pública en Nova Iguaçu, estado de Rio de Janeiro. Métodos: Se aplicó un sencillo cuestionario, que contenía datos demográficos, obstétricos y clínicos limitados, y se extrajo sangre en la misma visita. Se utilizaron diferentes kits de prueba comerciales basados en el ensayo inmunoabsorbente ligado a enzimas (ELISA). Resultados: De 349 mujeres embarazadas reclutadas de julio a diciembre de 2017, hubo serorreactividad de 28,4% para CHIKV, 47,2% para ZIKV y 88,8% para DENV. Conclusión: Estos hallazgos reflejan el escenario de alta endemicidad para el dengue y sugieren una variedad significativa de brotes recientes causados por ZIKV y CHIKV en la región.(AU)


Asunto(s)
Estudios Seroepidemiológicos , Dengue , Mujeres Embarazadas , Fiebre Chikungunya , Virus Zika
3.
Clin Case Rep ; 9(8)2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34178330

RESUMEN

Nonhospitalized COVID-19 and hepatitis C-coinfected patient presented prolonged RNA shedding and mild course of infection. This finding demonstrated the importance of long follow-up of these patients.

5.
Mem Inst Oswaldo Cruz ; 113(8): e170483, 2018 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-29898015

RESUMEN

In Brazil, detection of the HIV-1 sub-subtype F1 has decreased with a simultaneous increase in detection of the recombinant FB and FC forms. In previous HIV-1 env molecular epidemiology studies in Rio de Janeiro, 11.4% of the detected sequences were of the F1 sub-subtype. With the goal of re-estimating the prevalence of the HIV-1 F1 sub-subtype, we performed extended analyses of these samples by examining five genomic regions, resulting in 3.3% being confirmed as F1. Moreover, genomic analysis of 11 of the 21 samples identified as F1 confirmed that nine were F1 and two were BF1. Considering the number of samples assayed, the prevalence of F1 was quite low, which supports the use of different genomic regions for the assessment of HIV-1 classification in countries where several subtypes and recombinant forms co-circulate.


Asunto(s)
Genoma Viral/genética , Infecciones por VIH/epidemiología , Infecciones por VIH/virología , VIH-1/genética , Secuencia de Bases , Brasil/epidemiología , Genotipo , Humanos , Epidemiología Molecular , Filogenia , Análisis de Secuencia de ADN
6.
PLoS One ; 10(11): e0141372, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26536040

RESUMEN

Person who inject illicit substances have an important role in HIV-1 blood and sexual transmission and together with person who uses heavy non-injecting drugs may have less than optimal adherence to anti-retroviral treatment and eventually could transmit resistant HIV variants. Unfortunately, molecular biology data on such key population remain fragmentary in most low and middle-income countries. The aim of the present study was to assess HIV infection rates, evaluate HIV-1 genetic diversity, drug resistance, and to identify HIV transmission clusters in heavy drug users (DUs). For this purpose, DUs were recruited in the context of a Respondent-Driven Sampling (RDS) study in different Brazilian cities during 2009. Overall, 2,812 individuals were tested for HIV, and 168 (6%) of them were positive, of which 19 (11.3%) were classified as recent seroconverters, corresponding to an estimated incidence rate of 1.58%/year (95% CI 0.92-2.43%). Neighbor joining phylogenetic trees from env and pol regions and bootscan analyses were employed to subtype the virus from132 HIV-1-infected individuals. HIV-1 subtype B was prevalent in most of the cities under analysis, followed by BF recombinants (9%-35%). HIV-1 subtype C was the most prevalent in Curitiba (46%) and Itajaí (86%) and was also detected in Brasília (9%) and Campo Grande (20%). Pure HIV-1F infections were detected in Rio de Janeiro (9%), Recife (6%), Salvador (6%) and Brasília (9%). Clusters of HIV transmission were assessed by Maximum likelihood analyses and were cross-compared with the RDS network structure. Drug resistance mutations were verified in 12.2% of DUs. Our findings reinforce the importance of the permanent HIV-1 surveillance in distinct Brazilian cities due to viral resistance and increasing subtype heterogeneity all over Brazil, with relevant implications in terms of treatment monitoring, prophylaxis and vaccine development.


Asunto(s)
Farmacorresistencia Viral/genética , Infecciones por VIH/epidemiología , Infecciones por VIH/genética , VIH-1/genética , Abuso de Sustancias por Vía Intravenosa/epidemiología , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/genética , Adolescente , Adulto , Antirretrovirales/administración & dosificación , Brasil/epidemiología , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Masculino , Prevalencia
7.
Rio de Janeiro; s.n; 2015. xxi,95 p. ilus, tab, graf, mapas.
Tesis en Portugués | LILACS | ID: lil-774208

RESUMEN

O Vírus da Imunodeficiência Humana (HIV) tem extrema variabilidade genética resultante das altas taxas de mutação e recombinação, acarretados pela falta de atividade de revisão da transcriptase reversa,associado à alta taxa de replicação viral. [...] Estudos baseados na região do envelope viral detectam uma maior prevalência de subsubtipo F1 e menor de recombinantes BF1, já estudos com a região PR/RT encontram maior prevalência de BF1 e menor de F1. Assim, o presente estudo teve como objetivo reavaliar a caracterização molecular de um conjunto de amostras previamente classificadas como subsubtipo F1 apenas com a análise da região C2-V3 do envelope viral. Para tal, foram caracterizadas cinco regiões do genoma do HIV, incluindo as mais recombinogênicas, com a finalidade de estimar a prevalência real do subsubtipo F1, de realizar a dispersão temporal das amostras reclassificadas como subsubtipo F1 e recombinantes, e ainda compreender a complexidade dos perfis de recombinação. De um total de 635 amostras de HIV-1 positivas coletadas e previamente caracterizadas entre 1998-2013, 74 foram classificados como F1 na região C2-V3 env. Dessas, 56 possuíam amostras biológicas disponíveis e foram incluídas neste estudo. As amostras de DNA foram extraídas, amplificadas e sequenciadas nas regiões gag, PR / RT, INT, env e nef. As sequências foram alinhadas com amostras de referência do grupo M do HIV-1 pelo ClustalW...


Human Immunodeficiency vírus (HIV) has extreme genetic variability resulting from high mutation andrecombination rates, entailed by the lack of revision of reverse transcriptase activity associated with thehigh rate of viral replication. [...] Studies based on the viral envelope region detect higher prevalence of sub-subtype F1 and minor ofBF1recombinants, on the other hand studies on PR/RT region depicted higher prevalence of BF1 andminor of F1. Thus, this study aimed to review the molecular characterization of a set of samplespreviously classified as sub-subtype F1 only based in the analysis of the C2-V3 region of viral envelop.For this purpose, five regions were characterized genome of HIV, including the more recombinogenicones, in order to estimate the real prevalence F1 sub-subtype, to perform the temporal dispersion ofsamples reclassified as sub-subtype F1 and recombinants, and still understand the complexity ofrecombination profiles. From a total of 635 HIV-1 positive samples collected and previouslycharacterized between 1998-2013, 74 were classified as F1 based on C2-V3 env region. Of those, 56possessed available biological samples and were included in this study. The DNA samples wereextracted, amplified and sequenced regions in gag, PR / RT, INT, env and nef. The sequences werealigned with reference samples from HIV-1 group M by ClustalW...


Asunto(s)
Humanos , Síndrome de Inmunodeficiencia Adquirida , VIH-1 , Tipificación Molecular , Reacción en Cadena de la Polimerasa
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