Liver cirrhosis is a common and growing public health problem globally.The diagnosis of cirrhosis portends an increased risk of morbidity and mortality.Liver biopsy is considered the gold standard for diagnosis of cir...Liver cirrhosis is a common and growing public health problem globally.The diagnosis of cirrhosis portends an increased risk of morbidity and mortality.Liver biopsy is considered the gold standard for diagnosis of cirrhosis and staging of fibrosis.However,despite its universal use,liver biopsy is an invasive and inaccurate gold standard with numerous drawbacks.In order to overcome the limitations of liver biopsy,a number of non-invasive techniques have been investigated for the assessment of cirrhosis.This review will focus on currently available non-invasive markers of cirrhosis.The evidence behind the use of these markers will be highlighted,along with an assessment of diagnostic accuracy and performance characteristics of each test.Non-invasive markers of cirrhosis can be radiologic or serum-based.Radiologic techniques based on ultrasound,magnetic resonance imaging and elastography have been used to assess liver fibrosis.Serum-based biomarkers of cirrhosis have also been developed.These are broadly classified into indirect and direct markers.Indirect biomarkers reflect liver function,which may decline with the onset of cirrhosis.Direct biomarkers,reflect extracellular matrix turnover,and include molecules involved in hepatic fibrogenesis.On the whole,radiologic and serum markers of fibrosis correlate well with biopsy scores,especially when excluding cirrhosis or excluding fibrosis.This feature is certainly clinically useful,and avoids liver biopsy in many cases.展开更多
Impaired gene regulation lies at the heart of many disorders, including developmental diseases and cancer. Furthermore, the molecular pathways that control gene expression are often the target of cellular parasites, s...Impaired gene regulation lies at the heart of many disorders, including developmental diseases and cancer. Furthermore, the molecular pathways that control gene expression are often the target of cellular parasites, such as viruses. Gene expression is controlled through multiple mechanisms that are coordinated to ensure the proper and timely expression of each gene. Many of these mechanisms target the life cycle of the RNA molecule, from transcription to translation. Recently, another layer of regulation at the RNA level involving RNA modifications has gained renewed interest of the scientific community. The discovery that N6-methyladenosine （m6A）, a mod- ification present in mRNAs and long noncoding RNAs, can be removed by the activity of RNA demethylases, launched the field of epitranscriptomics; the study of how RNA function is regulated through the addition or removal of post-transcriptional modifications, similar to strategies used to regulate gene expression at the DNA and protein level. The abundance of RNA post-transcriptional modifications is determined by the activity of writer complexes （methylase） and eraser （RNA demethylase） proteins. Subsequently, the effects of RNA modifications materialize as changes in RNA structure and/or modulation of interactions between the modified RNA and RNA binding proteins or regulatory RNAs. Disruption of these pathways impairs gene expression and cellular function. This review focuses on the links between the RNA modification m6A and its implications in human diseases.展开更多
INTRODUCTIONHepatitis B virus (HBV) belongs to the group ofhepatovirus, a major pathogen of human acute andchronic hepatitis B[1 4], which has a very closeassociation with human hepatocellular carcinoma(HCC)[5-8], For...INTRODUCTIONHepatitis B virus (HBV) belongs to the group ofhepatovirus, a major pathogen of human acute andchronic hepatitis B[1 4], which has a very closeassociation with human hepatocellular carcinoma(HCC)[5-8], For example, a statistical data from ahospital in Shanghai showed that 80% of HCCpatients were positive for HBsAg ( personalcommunication).展开更多
文摘Liver cirrhosis is a common and growing public health problem globally.The diagnosis of cirrhosis portends an increased risk of morbidity and mortality.Liver biopsy is considered the gold standard for diagnosis of cirrhosis and staging of fibrosis.However,despite its universal use,liver biopsy is an invasive and inaccurate gold standard with numerous drawbacks.In order to overcome the limitations of liver biopsy,a number of non-invasive techniques have been investigated for the assessment of cirrhosis.This review will focus on currently available non-invasive markers of cirrhosis.The evidence behind the use of these markers will be highlighted,along with an assessment of diagnostic accuracy and performance characteristics of each test.Non-invasive markers of cirrhosis can be radiologic or serum-based.Radiologic techniques based on ultrasound,magnetic resonance imaging and elastography have been used to assess liver fibrosis.Serum-based biomarkers of cirrhosis have also been developed.These are broadly classified into indirect and direct markers.Indirect biomarkers reflect liver function,which may decline with the onset of cirrhosis.Direct biomarkers,reflect extracellular matrix turnover,and include molecules involved in hepatic fibrogenesis.On the whole,radiologic and serum markers of fibrosis correlate well with biopsy scores,especially when excluding cirrhosis or excluding fibrosis.This feature is certainly clinically useful,and avoids liver biopsy in many cases.
基金supported by the Intramural Research Program of the NIH,National Cancer Institute,Center for Cancer Research,United States of America
文摘Impaired gene regulation lies at the heart of many disorders, including developmental diseases and cancer. Furthermore, the molecular pathways that control gene expression are often the target of cellular parasites, such as viruses. Gene expression is controlled through multiple mechanisms that are coordinated to ensure the proper and timely expression of each gene. Many of these mechanisms target the life cycle of the RNA molecule, from transcription to translation. Recently, another layer of regulation at the RNA level involving RNA modifications has gained renewed interest of the scientific community. The discovery that N6-methyladenosine （m6A）, a mod- ification present in mRNAs and long noncoding RNAs, can be removed by the activity of RNA demethylases, launched the field of epitranscriptomics; the study of how RNA function is regulated through the addition or removal of post-transcriptional modifications, similar to strategies used to regulate gene expression at the DNA and protein level. The abundance of RNA post-transcriptional modifications is determined by the activity of writer complexes （methylase） and eraser （RNA demethylase） proteins. Subsequently, the effects of RNA modifications materialize as changes in RNA structure and/or modulation of interactions between the modified RNA and RNA binding proteins or regulatory RNAs. Disruption of these pathways impairs gene expression and cellular function. This review focuses on the links between the RNA modification m6A and its implications in human diseases.
基金This work was supported by Projects of Tackling Key Problems in ScienceTechnology from the State Science+2 种基金Technology Ministry (TJ99-LA01) Shanghai ScienceTechnology Commission (994919033 )
文摘INTRODUCTIONHepatitis B virus (HBV) belongs to the group ofhepatovirus, a major pathogen of human acute andchronic hepatitis B[1 4], which has a very closeassociation with human hepatocellular carcinoma(HCC)[5-8], For example, a statistical data from ahospital in Shanghai showed that 80% of HCCpatients were positive for HBsAg ( personalcommunication).
