Hepatitis C virus (HCV) infection is a major cause of liver damage, with virus-induced end-stage disease such as liver cirrhosis and hepatocellular carcinoma resulting in a high rate of morbidity and mortality worldwi...Hepatitis C virus (HCV) infection is a major cause of liver damage, with virus-induced end-stage disease such as liver cirrhosis and hepatocellular carcinoma resulting in a high rate of morbidity and mortality worldwide. Evidence that CD4+ T cell responses to HCV play an important role in the outcome of acute infection has been shown in several studies. However, the mechanisms behind viral persistence and the failure of CD4+ T cell responses to contain virus are poorly understood. During chronic HCV infection, HCV-specific CD4+ T cell responses are rela- tively weak or absent whereas in resolved infection these responses are vigorous and multispecific. Persons with a T-helper type I profile, which promotes cellular effec- tor mechanisms are thought to be more likely to experi- ence viral clearance, but the overall role of these cells in the immunopathogenesis of chronic liver disease is not known. To define this, much more data is required on the function and specificity of virus-specific CD4+ T cells, especially in the early phases of acute disease and in the liver during chronic infection. The role and possible mechanisms of action of CD4+ T cell responses in deter- mining the outcome of acute and chronic HCV infection will be discussed in this review.展开更多
Objective To evaluate the overexpression of cyclin G1 in cervical intraepithelial neoplasia （CIN） and cervical carcinoma, and the correlation between cyclin G1 and high-risk human papilloma virus （HPV） infection. ...Objective To evaluate the overexpression of cyclin G1 in cervical intraepithelial neoplasia （CIN） and cervical carcinoma, and the correlation between cyclin G1 and high-risk human papilloma virus （HPV） infection. Methods All of the specimens were obtained from the Department of Pathology of China-Japan Friendship Hospital from January 2000 to August 2004. We detected the expression of cyclin G1 with immunohistochemistry, HPV16/18 infection with in situ hybridization, and high-risk HPV infection with Hybrid capture system Ⅱ （HC-Ⅱ） in normal group （25 cases）, CIN Ⅰ （48 cases）, CIN Ⅱ （56 cases）, CIN Ⅲ（54 cases）, and invasive cervical squamous-cell carcinoma （SCC, 31 cases）. Results The positive rates of cyclin G1 expression in CIN（77.85% ）and SCC cervical tissues （87. 10% ） were significantly higher than normal （ 8.00%, P 〈 0. 01 ）, and the intensities of cyclin G1 expression in CIN（40. 60% ） and SCC cervical tissues （61.51%） were significantly higher than normal （2. 72%, P 〈0.05）. The positive rates and intensities of cyclin G1 expression increased gradually with the grade of cervical lesions. High-risk HPV infection rates were higher in CIN and SCC than normal groups （P 〈 0.05 ）. There was a positive correlation between cyclin G1 expression and high-risk HPV infection detected with HC-Ⅱ （Kendall＇s tau-b =0. 316, 0. 269, 0. 352, and 0. 474 in CIN Ⅰ, CIN Ⅱ, CIN Ⅲ, and SCC, respectively, P 〈 0. 05 ）. Conclusions Cyclin G1 is overexpressed in CIN and SCC. Cyclin G1 may be a biomarker for detecting CIN and SCC. Cyclin G1 may play an important role in the oncogenesis of CIN and SCC by high-risk HPV infection.展开更多
Alcoholic patients have a high incidence of hepatitis C virus （HCV） infection. Alcohol consumption enhances the severity of the HCV disease course and worsens the outcome of chronic hepatitis C. The accumulation of ...Alcoholic patients have a high incidence of hepatitis C virus （HCV） infection. Alcohol consumption enhances the severity of the HCV disease course and worsens the outcome of chronic hepatitis C. The accumulation of virally infected cells in the liver is related to the HCV- induced inability of the immune system to recognize infected cells and to develop the immune responses. This review covers the effects of HCV proteins and ethanol on major histocompatibility complex （MHC） class Ⅰ- and class Ⅱ-restricted antigen presentation. Here, we discuss the liver which functions as an immune privilege organ; factors, which affect cleavage and loading of antigenic peptides onto MHC class I and class ~I in hepatocytes and dendritic cells, and the modulating effects of ethanol and HCV on antigen presentation by liver cells. Altered antigen presentation in the liver limits the ability ＇of the immune system to clear HCV and infected cells and contributes to disease progression. HCV by itself affects dendritic cell function, switching their cytokine profile to the suppressive phenotype of interleukin-10 （IL-10） and transforming growth factor beta （TGFβ） predominance, preventing cell maturation and allostimulation capacity. The synergistic action of ethanol with HCV results in the suppression of MHC class Ⅱ-restricted antigen presentation. In addition, ethanol metabolism and HCV proteins reduce proteasome function and interferon signaling, thereby suppressing the generation of peptides for MHC class I -restricted antigen presentation. Collectively, ethanol exposure further impairs antigen presentation in HCV-infected liver cells, which may provide a partial explanation for exacerbations and the poor outcome of HCV infection in alcoholics.展开更多
AIM: To characterize the nuclear import of hepatitis B virus (HBV) polymerase (P) and its relevance for the viral life cycle.METHODS: Sequence analysis was performed to predict functional motives within P. Phosphoryla...AIM: To characterize the nuclear import of hepatitis B virus (HBV) polymerase (P) and its relevance for the viral life cycle.METHODS: Sequence analysis was performed to predict functional motives within P. Phosphorylation of P was analyzed by in vitro phosphorylation. Phosphorylation site and nuclear localization signal (NLS) were destroyed by site directed mutagenesis. Functionality of the identified NLS was analyzed by confocal fluorescence microscopy and characterizing the karyopherin binding. Relevance of the structural motives for viral life cycle was studied by infection of primary Tupaia hepatocytes with HBV.RESULTS: We identified by sequence alignment and functional experiments a conserved bipartite NLS containing a casein kinase II (CKII) phosphorylation site located within the terminal protein domain (TP) of the HBV polymerase. Inhibition of CKII impairs the functionality of this NLS and thereby prevents the nuclear import of the polymerase. Binding of the import factor karyopherin-α2 to the polymerase depends on its CKII-mediated phosphorylation of the bipartite NLS. In HBV-infected primary Tupaia hepatocytes CKII inhibition in the early phase (post entry phase) of the infection process prevents the establishment of the infection.CONCLUSION: Based on these data it is suggested that during HBV infection the final import of the genome complex into the nucleus is mediated by a novel bipartite NLS localized in the TP domain of HBV polymerase.展开更多
BACKGROUND The lymphocyte-to-white blood cell ratio(LWR)is a blood marker of the systemic inflammatory response.The prognostic value of LWR in patients with hepatitis B virus-associated acute-on-chronic liver failure(...BACKGROUND The lymphocyte-to-white blood cell ratio(LWR)is a blood marker of the systemic inflammatory response.The prognostic value of LWR in patients with hepatitis B virus-associated acute-on-chronic liver failure(HBV-ACLF)remains unclear.AIM To explore whether LWR could stratify the risk of poor outcomes in HBV-ACLF patients.METHODS This study was conducted by recruiting 330 patients with HBV-ACLF at the Department of Gastroenterology in a large tertiary hospital.Patients were divided into survivor and non-survivor groups according to their 28-d prognosis.The independent risk factors for 28-d mortality were calculated by univariate and multivariate Cox regression analyses.Patients were divided into low-and high-LWR groups according to the cutoff values.Kaplan-Meier analysis was performed according to the level of LWR.RESULTS During the 28-d follow-up time,135 patients died,and the mortality rate was 40.90%.The LWR level in non-surviving patients was significantly decreased compared to that in surviving patients.A lower LWR level was an independent risk factor for poor 28-d outcomes(hazard ratio=0.052,95%confidence interval:0.005-0.535).The LWR level was significantly negatively correlated with the Child-Turcotte-Pugh,model for end-stage liver disease,and Chinese Group on the Study of Severe Hepatitis B-ACLF II scores.In addition,the 28-d mortality was higher for patients with LWR<0.11 than for those with LWR≥0.11.CONCLUSION LWR may serve as a simple and useful tool for stratifying the risk of poor 28-d outcomes in HBVACLF patients.展开更多
基金the Deutsche Forschungsgemeinschaft and the Wellcome Trust and the James Martin School for the 21st century, Oxford
文摘Hepatitis C virus (HCV) infection is a major cause of liver damage, with virus-induced end-stage disease such as liver cirrhosis and hepatocellular carcinoma resulting in a high rate of morbidity and mortality worldwide. Evidence that CD4+ T cell responses to HCV play an important role in the outcome of acute infection has been shown in several studies. However, the mechanisms behind viral persistence and the failure of CD4+ T cell responses to contain virus are poorly understood. During chronic HCV infection, HCV-specific CD4+ T cell responses are rela- tively weak or absent whereas in resolved infection these responses are vigorous and multispecific. Persons with a T-helper type I profile, which promotes cellular effec- tor mechanisms are thought to be more likely to experi- ence viral clearance, but the overall role of these cells in the immunopathogenesis of chronic liver disease is not known. To define this, much more data is required on the function and specificity of virus-specific CD4+ T cells, especially in the early phases of acute disease and in the liver during chronic infection. The role and possible mechanisms of action of CD4+ T cell responses in deter- mining the outcome of acute and chronic HCV infection will be discussed in this review.
文摘Objective To evaluate the overexpression of cyclin G1 in cervical intraepithelial neoplasia （CIN） and cervical carcinoma, and the correlation between cyclin G1 and high-risk human papilloma virus （HPV） infection. Methods All of the specimens were obtained from the Department of Pathology of China-Japan Friendship Hospital from January 2000 to August 2004. We detected the expression of cyclin G1 with immunohistochemistry, HPV16/18 infection with in situ hybridization, and high-risk HPV infection with Hybrid capture system Ⅱ （HC-Ⅱ） in normal group （25 cases）, CIN Ⅰ （48 cases）, CIN Ⅱ （56 cases）, CIN Ⅲ（54 cases）, and invasive cervical squamous-cell carcinoma （SCC, 31 cases）. Results The positive rates of cyclin G1 expression in CIN（77.85% ）and SCC cervical tissues （87. 10% ） were significantly higher than normal （ 8.00%, P 〈 0. 01 ）, and the intensities of cyclin G1 expression in CIN（40. 60% ） and SCC cervical tissues （61.51%） were significantly higher than normal （2. 72%, P 〈0.05）. The positive rates and intensities of cyclin G1 expression increased gradually with the grade of cervical lesions. High-risk HPV infection rates were higher in CIN and SCC than normal groups （P 〈 0.05 ）. There was a positive correlation between cyclin G1 expression and high-risk HPV infection detected with HC-Ⅱ （Kendall＇s tau-b =0. 316, 0. 269, 0. 352, and 0. 474 in CIN Ⅰ, CIN Ⅱ, CIN Ⅲ, and SCC, respectively, P 〈 0. 05 ）. Conclusions Cyclin G1 is overexpressed in CIN and SCC. Cyclin G1 may be a biomarker for detecting CIN and SCC. Cyclin G1 may play an important role in the oncogenesis of CIN and SCC by high-risk HPV infection.
基金Supported by Development funds from Section of Gastroenterology/Hepatology, Internal Medicine, University of Nebraska Medical Center
文摘Alcoholic patients have a high incidence of hepatitis C virus （HCV） infection. Alcohol consumption enhances the severity of the HCV disease course and worsens the outcome of chronic hepatitis C. The accumulation of virally infected cells in the liver is related to the HCV- induced inability of the immune system to recognize infected cells and to develop the immune responses. This review covers the effects of HCV proteins and ethanol on major histocompatibility complex （MHC） class Ⅰ- and class Ⅱ-restricted antigen presentation. Here, we discuss the liver which functions as an immune privilege organ; factors, which affect cleavage and loading of antigenic peptides onto MHC class I and class ~I in hepatocytes and dendritic cells, and the modulating effects of ethanol and HCV on antigen presentation by liver cells. Altered antigen presentation in the liver limits the ability ＇of the immune system to clear HCV and infected cells and contributes to disease progression. HCV by itself affects dendritic cell function, switching their cytokine profile to the suppressive phenotype of interleukin-10 （IL-10） and transforming growth factor beta （TGFβ） predominance, preventing cell maturation and allostimulation capacity. The synergistic action of ethanol with HCV results in the suppression of MHC class Ⅱ-restricted antigen presentation. In addition, ethanol metabolism and HCV proteins reduce proteasome function and interferon signaling, thereby suppressing the generation of peptides for MHC class I -restricted antigen presentation. Collectively, ethanol exposure further impairs antigen presentation in HCV-infected liver cells, which may provide a partial explanation for exacerbations and the poor outcome of HCV infection in alcoholics.
文摘AIM: To characterize the nuclear import of hepatitis B virus (HBV) polymerase (P) and its relevance for the viral life cycle.METHODS: Sequence analysis was performed to predict functional motives within P. Phosphorylation of P was analyzed by in vitro phosphorylation. Phosphorylation site and nuclear localization signal (NLS) were destroyed by site directed mutagenesis. Functionality of the identified NLS was analyzed by confocal fluorescence microscopy and characterizing the karyopherin binding. Relevance of the structural motives for viral life cycle was studied by infection of primary Tupaia hepatocytes with HBV.RESULTS: We identified by sequence alignment and functional experiments a conserved bipartite NLS containing a casein kinase II (CKII) phosphorylation site located within the terminal protein domain (TP) of the HBV polymerase. Inhibition of CKII impairs the functionality of this NLS and thereby prevents the nuclear import of the polymerase. Binding of the import factor karyopherin-α2 to the polymerase depends on its CKII-mediated phosphorylation of the bipartite NLS. In HBV-infected primary Tupaia hepatocytes CKII inhibition in the early phase (post entry phase) of the infection process prevents the establishment of the infection.CONCLUSION: Based on these data it is suggested that during HBV infection the final import of the genome complex into the nucleus is mediated by a novel bipartite NLS localized in the TP domain of HBV polymerase.
基金Supported by the National Natural Science Foundation of China,No.81960120 and 81660110the Postgraduate Innovation Special Foundation of Jiangxi Province,No.YC2022-B052“Gan-Po Talent 555”Project of Jiangxi Province,No.GCZ(2012)-1.
文摘BACKGROUND The lymphocyte-to-white blood cell ratio(LWR)is a blood marker of the systemic inflammatory response.The prognostic value of LWR in patients with hepatitis B virus-associated acute-on-chronic liver failure(HBV-ACLF)remains unclear.AIM To explore whether LWR could stratify the risk of poor outcomes in HBV-ACLF patients.METHODS This study was conducted by recruiting 330 patients with HBV-ACLF at the Department of Gastroenterology in a large tertiary hospital.Patients were divided into survivor and non-survivor groups according to their 28-d prognosis.The independent risk factors for 28-d mortality were calculated by univariate and multivariate Cox regression analyses.Patients were divided into low-and high-LWR groups according to the cutoff values.Kaplan-Meier analysis was performed according to the level of LWR.RESULTS During the 28-d follow-up time,135 patients died,and the mortality rate was 40.90%.The LWR level in non-surviving patients was significantly decreased compared to that in surviving patients.A lower LWR level was an independent risk factor for poor 28-d outcomes(hazard ratio=0.052,95%confidence interval:0.005-0.535).The LWR level was significantly negatively correlated with the Child-Turcotte-Pugh,model for end-stage liver disease,and Chinese Group on the Study of Severe Hepatitis B-ACLF II scores.In addition,the 28-d mortality was higher for patients with LWR<0.11 than for those with LWR≥0.11.CONCLUSION LWR may serve as a simple and useful tool for stratifying the risk of poor 28-d outcomes in HBVACLF patients.
