Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 2 de 2
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Rev. moçamb. ciênc. saúde ; 5(1): 29-33, Abr. 2019. tab
Artigo em Português | AIM (África), RDSM | ID: biblio-1381076

RESUMO

Foi realizado um estudo descritivo transversal com abordagem quantitativa para identificar a frequência dos factores de risco associados a co-infecção pelo vírus de Hepatite B (HBV) e vírus de imunodeficiência Humana (HIV) em doadores de sangue repositores, no 2otrimestre de 2015. O estudo foi realizado no Banco de Sangue do Hospital Central de Ma puto (HCM) e do Hospital Provincial de Xai-Xai (HPXX). Constituiu população deste estudo os doadores repositores de sangue das duas Unidades Sanitárias. Foram inqueridos 240 doadores repositores de sangue para identificar os factores de risco associados a co-infecção entre HBV/HIV e determinou-se a frequência através dos dados obtidos do registo do trabalho de rotina. A frequência da Hepatite B foi de 5,0% (12/240), de HIV foi de 5,8% (14/240). A monoinfecção por HBV foi de 5,2% (7/120) no HCM, 6,7% (8/120) no HPXX e de HIV foi de 4,2% (5/120) no HCM e 5% (6/120) no HPXX. A co-infecção total de HBV/HIV foi de 1,3% (3/240) sendo no HCM de 0,8% (1/120) e 1,7% (2/120) no HPXX. Ser comerciante, estar internado por mais de uma semana e com história de uso da droga injectável são factores de risco associados a infecção pelo HBV. Não foi possível associar os factores de risco investigados à monoinfecção por HIV neste estudo.


A cross-sectional descriptive study with a quantitative approach was carried out to identify the frequency of risk factors associated with co-infection with Hepatitis B virus (HBV) and Human Immunodeficiency Virus (HIV) in replacement blood donors, in the 2nd quarter of 2015. The study was carried out at the Blood Bank of the Hospital Central de Maputo (HCM) and the Hospital Provincial de Xai-Xai (HPXX). The population of this study consisted of blood replacement donors from the two Health Units. 240 blood replacement donors were surveyed to identify risk factors associated with HBV/HIV co-infection and frequency was determined through data obtained from routine work records. The frequency of Hepatitis B was 5.0% (12/240), of HIV was 5.8% (14/240). HBV monoinfection was 5.2% (7/120) in HCM, 6.7% (8/120) in HPXX and HIV was 4.2% (5/120) in HCM and 5% (6 /120) on HPXX. The total co-infection of HBV/HIV was 1.3% (3/240) being 0.8% (1/120) in HCM and 1.7% (2/120) in HPXX. Being a trader, being hospitalized for more than a week and having a history of injecting drug use are risk factors associated with HBV infection. It was not possible to associate the investigated risk factors with HIV monoinfection in this study.


Assuntos
Humanos , Masculino , Feminino , Doadores de Sangue , Vírus , Sangue , Hepadnaviridae/efeitos da radiação , Risco , Prevalência , HIV/crescimento & desenvolvimento , Hepatite B/diagnóstico , Hepatite Crônica/tratamento farmacológico , Infecções
2.
J Virol ; 88(24): 14105-15, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25253350

RESUMO

UNLABELLED: Woodchuck hepatitis virus (WHV), a close relative of human hepatitis B virus (HBV), has been a key model for disease progression and clinical studies. Sequences of the assembly domain of WHV and HBV core proteins (wCp149 and hCp149, respectively) have 65% identity, suggesting similar assembly behaviors. We report a cryo-electron microscopy (cryo-EM) structure of the WHV capsid at nanometer resolution and characterization of wCp149 assembly. At this resolution, the T=4 capsid structures of WHV and HBV are practically identical. In contrast to their structural similarity, wCp149 demonstrates enhanced assembly kinetics and stronger dimer-dimer interactions than hCp149: at 23 °C and at 100 mM ionic strength, the pseudocritical concentrations of assembly of wCp149 and hCp149 are 1.8 µM and 43.3 µM, respectively. Transmission electron microscopy reveals that wCp149 assembles into predominantly T=4 capsids with a sizeable population of larger, nonicosahedral structures. Charge detection mass spectrometry indicates that T=3 particles are extremely rare compared to the ∼ 5% observed in hCp149 reactions. Unlike hCp149, wCp149 capsid assembly is favorable over a temperature range of 4 °C to 37 °C; van't Hoff analyses relate the differences in temperature dependence to the high positive values for heat capacity, enthalpy, and entropy of wCp149 assembly. Because the final capsids are so similar, these findings suggest that free wCp149 and hCp149 undergo different structural transitions leading to assembly. The difference in the temperature dependence of wCp149 assembly may be related to the temperature range of its hibernating host. IMPORTANCE: In this paper, we present a cryo-EM structure of a WHV capsid showing its similarity to HBV. We then observe that the assembly properties of the two homologous proteins are very different. Unlike human HBV, the capsid protein of WHV has evolved to function in a nonhomeostatic environment. These studies yield insight into the interplay between core protein self-assembly and the host environment, which may be particularly relevant to plant viruses and viruses with zoonotic cycles involving insect vectors.


Assuntos
Hepadnaviridae/fisiologia , Vírus da Hepatite B da Marmota/fisiologia , Proteínas do Core Viral/metabolismo , Vírion/metabolismo , Montagem de Vírus/efeitos da radiação , Sequência de Aminoácidos , Animais , Microscopia Crioeletrônica , Hepadnaviridae/efeitos da radiação , Hepadnaviridae/ultraestrutura , Vírus da Hepatite B da Marmota/efeitos da radiação , Vírus da Hepatite B da Marmota/ultraestrutura , Humanos , Espectrometria de Massas , Microscopia Eletrônica de Transmissão , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Alinhamento de Sequência , Temperatura , Vírion/ultraestrutura
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...