Occult hepatitis B virus (HBV) infection (OBI), alternatively defined as occult hepatitis B (OHB), is a challenging clinical entity. It is recognized by two main characteristics: absence of HBsAg, and low viral replic...Occult hepatitis B virus (HBV) infection (OBI), alternatively defined as occult hepatitis B (OHB), is a challenging clinical entity. It is recognized by two main characteristics: absence of HBsAg, and low viral replication. The previous two decades have witnessed a remarkable progress in our understanding of OBI and its clinical implications. Appropriate diagnostic techniques must be adopted. Sensitive HBV DNA amplification assay is the gold standard assay for detection of OBI. Viral as well as host factors are implicated in the pathogenesis of OBI. However, published data reporting the infectivity of OBI by transfusion are limited. Several aspects including OBI transmission, infectivity and its relation to the development of chronic liver diseases and hepatocellular carcinoma have to be resolved. The aim of the present review is to highlight recent data on OBI with a focus on its virological diagnosis and clinical outcome.展开更多
DNA methylation is an important component of the epigenetic network, and it plays important roles in gene expression regulation and epigenetic change response to various stresses. In this study, the authors assessed t...DNA methylation is an important component of the epigenetic network, and it plays important roles in gene expression regulation and epigenetic change response to various stresses. In this study, the authors assessed the methylation patterns stressed by SCMV (sugarcane mosaic virus) in maize by methylation-sensitive amplified polymorphism (MSAP), and identified important candidate genes related to SCMV resistance through combining microarray analysis with CpG islands prediction. The results of MSAP indicated DNA methylation levels appeared dynamic changes inoculated for 0 d, 1 d, 4 d, 5 d and 10 d. 118 candidate genes were identified infected by SCMV, which may participate in DNA methylation modification. Among them, eight candidate genes were mapped on Scmvl and Scmv2 QTL regions, which are crucial for SCMV resistance. In conclusion, DNA methylation is closely related with maize resistance to SCMV and plays an important role in regulating gene expression responded to maize resistance.展开更多
文摘Occult hepatitis B virus (HBV) infection (OBI), alternatively defined as occult hepatitis B (OHB), is a challenging clinical entity. It is recognized by two main characteristics: absence of HBsAg, and low viral replication. The previous two decades have witnessed a remarkable progress in our understanding of OBI and its clinical implications. Appropriate diagnostic techniques must be adopted. Sensitive HBV DNA amplification assay is the gold standard assay for detection of OBI. Viral as well as host factors are implicated in the pathogenesis of OBI. However, published data reporting the infectivity of OBI by transfusion are limited. Several aspects including OBI transmission, infectivity and its relation to the development of chronic liver diseases and hepatocellular carcinoma have to be resolved. The aim of the present review is to highlight recent data on OBI with a focus on its virological diagnosis and clinical outcome.
文摘DNA methylation is an important component of the epigenetic network, and it plays important roles in gene expression regulation and epigenetic change response to various stresses. In this study, the authors assessed the methylation patterns stressed by SCMV (sugarcane mosaic virus) in maize by methylation-sensitive amplified polymorphism (MSAP), and identified important candidate genes related to SCMV resistance through combining microarray analysis with CpG islands prediction. The results of MSAP indicated DNA methylation levels appeared dynamic changes inoculated for 0 d, 1 d, 4 d, 5 d and 10 d. 118 candidate genes were identified infected by SCMV, which may participate in DNA methylation modification. Among them, eight candidate genes were mapped on Scmvl and Scmv2 QTL regions, which are crucial for SCMV resistance. In conclusion, DNA methylation is closely related with maize resistance to SCMV and plays an important role in regulating gene expression responded to maize resistance.