AIM Toll like receptors plays a significant anti-viral role in different infections. The aim of this study was to look into the role of toll like receptor 4(TLR4) in hepatitis B virus(HBV) infection.METHODS Real time ...AIM Toll like receptors plays a significant anti-viral role in different infections. The aim of this study was to look into the role of toll like receptor 4(TLR4) in hepatitis B virus(HBV) infection.METHODS Real time PCR was used to analyze the transcription of TLR4 signaling molecules, cell cycle regulators and HBV DNA viral load after triggering the Hep G2.2.15 cells with TLR4 specific ligand. Nuclear factor(NF)-κB translocation on TLR4 activation was analyzed using microscopic techniques. Protein and cell cycle analysis was done using Western Blot and FACS respectively.RESULTS The present study shows that TLR4 activation represses HBV infection. As a result of HBV suppression, there are several changes in host factors which include partial release in G1/S cell cycle arrest and changes in host epigenetic marks. Finally, it was observed that anti-viral action of TLR4 takes place through the NF-κB pathway.CONCLUSION The study shows that TLR4 activation in HBV infection brings about changes in hepatocyte microenvironment and can be used for developing a promising therapeutic target in future.展开更多
AIM: To evaluate the genotype distribution of hepatitis B virus (HBV) in Eastern India and to clarify the phyloge- netic origin and virological characteristics of the recently identifi ed genotype C in this region. ME...AIM: To evaluate the genotype distribution of hepatitis B virus (HBV) in Eastern India and to clarify the phyloge- netic origin and virological characteristics of the recently identifi ed genotype C in this region. METHODS: Genotype determination, T1762/A1764 mutation in the basal core promoter (BCP) and A1896 mutation in the precore region of 230 subjects were de- termined by restriction fragment length polymorphism method (RFLP) and the result was confi rmed by direct sequencing. RESULTS: The predominant genotypes D (HBV/D) and A (HBV/A) were detected in 131/230 (57%) and 57/230 (25%) samples. In addition, genotype C (HBV/C) was detected in 42/230 (18%) isolates. Surface gene region was sequenced from 45 isolates (27 HBV/C, 9 HBV/A and 9 HBV/D). Phylogenetic analysis revealed that all of the HBV/C sequences clustered with South East Asian subgenotype (HBV/Cs). The sequence data showed re- markable similarity with a Thai strain (AF068756) (99.5% ± 0.4% nucleotide identities) in 90% of the genotype C strains analyzed. T1762/A1764 mutation in BCP re- gion, associated with high ALT was signifi cantly higher in HBeAg negative isolates than HBeAg positive isolates. Frequency of A1896 mutation leading to HBeAg negativ- ity was low.CONCLUSION: The present study reports the genotypic distribution and the characteristics of partial genome sequences of HBV/C isolates from Eastern India. Low genetic diversity and confi nement of HBV/C in Eastern India possibly indicate a recent, limited, spread in this region. Genotype C with T1762/A1764 mutation has been reported to increase the risk for hepatocellular car- cinoma; therefore genotype C carriers in Eastern India should be carefully monitored.展开更多
Hepatitis C virus(HCV) is an emerging infection worldwide and the numbers of persons infected are increasing every year. Poor blood transfusion methods along with unsafe injection practices are potential sources for t...Hepatitis C virus(HCV) is an emerging infection worldwide and the numbers of persons infected are increasing every year. Poor blood transfusion methods along with unsafe injection practices are potential sources for the rapid spread of infection. Early detection of HCV is the need of the hour especially in high riskgroup population as these individuals are severely immunocompromised. Enzyme Immunoassays are the most common detection techniques but they provide no evidence of active viremia or identification of infected individuals in the antibody-negative phase and their efficacy is limited in individuals within high risk group population. Molecular virological techniques have an important role in detecting active infection with utmost specificity and sensitivity. Technologies for assessment of HCV antibody and RNA levels have improved remarkably, as well as our understanding of how to best use these tests in patient management. This review aims to give an overview of the different serological and molecular methods employed in detecting HCV infection used nowadays. Additionally, the review gives an insight in the new molecular techniques that are being developed to improve the detection techniques particularly in High Risk Group population who are severely immunocompromised.展开更多
Shared routes of transmission lead to frequent human immunodeficiency virus(HIV)-hepatitis B virus(HBV) coinfection in a host which results in about 10% of HIV positive individuals to have chronic hepatitis B infectio...Shared routes of transmission lead to frequent human immunodeficiency virus(HIV)-hepatitis B virus(HBV) coinfection in a host which results in about 10% of HIV positive individuals to have chronic hepatitis B infection worldwide. In post-antiretroviral therapy era, liverdiseases have emerged as the leading cause of morbidity and mortality in HIV-infected individuals and HBV coinfection have become the major health issue among this population particularly from the regions with endemic HBV infection. In setting of HIV-HBV co-infection, HIV significantly impacts the natural history of HBV infection, its disease profile and the treatment outcome in negative manner. Moreover, the epidemiological pattern of HBV infection and the diversity in HBV genome(genotypic and phenotypic) are also varied in HIV co-infected subjects as compared to HBV mono-infected individuals. Several reports on the abovementioned issues are available from developed parts of the world as well as from sub-Saharan African countries. In contrast, most of these research areas remained unexplored in India despite having considerable burden of HIV and HBV infections. This review discusses present knowledge from the studies on HIV-HBV co-infection in India and relevant reports from different parts of the world. Issues needed for the future research relevant to HIV-HBV co-infection in India are also highlighted here, including a call for further investigations on this field of study.展开更多
AIM To investigate the role of subgenotype specific RNA secondary structure in the compartment specific selection of hepatitis B virus(HBV)immune escape mutations.METHODS This study was based on the analysis of the sp...AIM To investigate the role of subgenotype specific RNA secondary structure in the compartment specific selection of hepatitis B virus(HBV)immune escape mutations.METHODS This study was based on the analysis of the specific observation of HBV subgenotype A1 in the serum/plasma,while subgenotype A2 with G145R mutation in the peripheral blood leukocytes(PBLs).Genetic variability found among the two subgenotypes was used for prediction and comparison of the full length pregenomic RNA(pgRNA)secondary structure and base pairings.RNA secondary structures were predicted for 37℃using the Vienna RNA fold server,using default parameters.Visualization and detailed analysis was done using RNA shapes program.RESULTS In this analysis,using similar algorithm and conditions,entirely different pgRNA secondary structures for subgenotype A1 and subgenotype A2 were predicted,suggesting different base pairing patterns within the two subgenotypes of genotype A,specifically,in the HBV genetic region encoding the major hydrophilic loop.We observed that for subgenotype A1 specific pgRNA,nucleotide 358U base paired with 1738A and nucleotide 587G base paired with 607C.However in sharp contrast,in subgenotype A2 specific pgRNA,nucleotide 358U was opposite to nucleotide 588G,while 587G was opposite to 359U,hence precluding correct base pairing and thereby lesser stability of the stem structure.When the nucleotides at 358U and 587G were replaced with 358C and 587A respectively(as observed specifically in the PBL associated A2 sequences),these nucleotides base paired correctly with 588G and 359U,respectively.CONCLUSION The results of this study show that compartment specific mutations are associated with HBV subgenotype specific alterations in base pairing of the pgRNA,leading to compartment specific selection and preponderance of specific HBV subgenotype with unique mutational pattern.展开更多
Human immunodeficiency virus(HIV) infection among men who have sex with men(MSM) has increased to a drastic proportion throughout India in the last couple of years due to a lack of productive identification and manage...Human immunodeficiency virus(HIV) infection among men who have sex with men(MSM) has increased to a drastic proportion throughout India in the last couple of years due to a lack of productive identification and management framework. In apprehension of social disgrace these men attempt to live a normal hetero conjugal life and, in the process, act as a bridge in spreading the virus to their women partners. In this case report we have highlighted two cases which clearly distinguished the adequacy of HIV treatment among MSM when they are diagnosed during early or late phases of infection. An intensive and ample counseling to comprehend the psychology and sexual behavior of these men was found to be critically important in both the cases. Our study, which is actually the first of its kind, recorded and documented evidence of HIV infected MSM from Eastern India and renders a ray of hope among this marginally isolated group to comprehend the challenges and health risks faced by the MSM population. It also provides a format for the medical practitioners here in managing and treating related cases.展开更多
AIM: To evaluate the prevalence of markers of hepatitis B virus (HBV) and hepatitis C virus (HCV) and human immunodeficiency virus (HIV) among blood donors in Kolkata, Eastern India for two consecutive years and to co...AIM: To evaluate the prevalence of markers of hepatitis B virus (HBV) and hepatitis C virus (HCV) and human immunodeficiency virus (HIV) among blood donors in Kolkata, Eastern India for two consecutive years and to conduct a pilot study to explore the presence of HBV DNA among hepatitis B surface antigen (HBsAg) negative but anti-HBc positive blood donors. METHODS: Seroprevalence of HBsAg, anti-HCV and anti-HIV was studied among 113 051 and 106 695 voluntary blood donors screened in 2004 and 2005, respectively. Moreover, a pilot study on 1027 HBsAg negative donors was carried out for evaluating the presence of HBV DNA by PCR on HBsAg negative/anti- HBc positive donors. RESULTS: A statistically significant increase in the prevalence of HBV (1448 vs 1768, P < 0.001), HIV (262 vs 374, P < 0.001), HCV (314 vs 372, P = 0.003) and syphilis (772 vs 853, P = 0.001) infections was noted among blood donors of Kolkata West Bengal in 2005 as compared to 2004. Moreover, the exploratory study on 1027 HBsAg negative donors revealed that 188 (18.3%)of them were anti-HBc positive out of which 21% were positive for HBV DNA. CONCLUSION: The findings of this study underscore the significantly increasing endemicity of hepatitis viruses, syphilis and HIV among the voluntary blood donors of our community. The pilot study indicates a high rate of prevalence of HBV DNA among HBsAg negative/anti-HBc positive donors and thus emphasizes the need for a more sensitive and stringent screening algorithm for blood donations.展开更多
Objective:To investigate the outbreak of unknown fever at Siliguri town,Darjeeling District on request from the State Health Department,Government of West Bengal.Methods: Investigations were made to the affected wards...Objective:To investigate the outbreak of unknown fever at Siliguri town,Darjeeling District on request from the State Health Department,Government of West Bengal.Methods: Investigations were made to the affected wards,Sub Divisional Hospital and the nursing homes of Siliguri Town.Duration of illness was 3-5 days.Interesting observations were made in some cases which had gastrointestinal disorders with high serum glutamate pyruvate transaminase(SGPT) and serum glutamic oxaloacetic transaminase(SCOT) levels.A total of 69 blood samples and 7 throat swabs(in Minimum Essential Media) were collected and brought to the ICMR Virus Unit, Kolkata for analysis.Mosquitoes from different affected areas were collected for the identification of the definite vector.Results:Amongst the 69 blood samples,42(60.86%) were positive to IgM antibody against dengue virus by Mac enzyme-linked immunosorbent assay(ELISA) test.No IgM antibody to Japanese encephalitis virus was detected among the collected blood samples.Based on the clinical symptoms,presence of IgM antibody to dengue virus and identification of Aedes mosquito,it amply proves that,the illness of those cases were due to dengue virus infection. Conclusions:Based on clinical-epidemiological observations of the investigations the possibility of a communicable disease of viral origin,the detection of IgM antibody and the identification of Aedes egypti,and the potential circulation of denge virus in Siliguri town for the first time were all suggested.展开更多
基金Supported by the Indian Council of Medical Research(ICMR)intramural projectDas C acknowledges the financial support from Biomolecular Assembly,Recognition and Dynamics (BARD) project(Grant 12-R&D-SIN-5.04-0103)from Department of Atomic Energy(DAE),Government of India and Ramalingaswami Fellowship,Department of Biotechnology,Government of India
文摘AIM Toll like receptors plays a significant anti-viral role in different infections. The aim of this study was to look into the role of toll like receptor 4(TLR4) in hepatitis B virus(HBV) infection.METHODS Real time PCR was used to analyze the transcription of TLR4 signaling molecules, cell cycle regulators and HBV DNA viral load after triggering the Hep G2.2.15 cells with TLR4 specific ligand. Nuclear factor(NF)-κB translocation on TLR4 activation was analyzed using microscopic techniques. Protein and cell cycle analysis was done using Western Blot and FACS respectively.RESULTS The present study shows that TLR4 activation represses HBV infection. As a result of HBV suppression, there are several changes in host factors which include partial release in G1/S cell cycle arrest and changes in host epigenetic marks. Finally, it was observed that anti-viral action of TLR4 takes place through the NF-κB pathway.CONCLUSION The study shows that TLR4 activation in HBV infection brings about changes in hepatocyte microenvironment and can be used for developing a promising therapeutic target in future.
基金Supported by Indian Council of Medical Research, Government of India. Arup Banerjee and Sibnarayan Datta are recipient of senior research fellowship of the Indian Council of Medical Research and University Grants Commission, Government of India, respectively
文摘AIM: To evaluate the genotype distribution of hepatitis B virus (HBV) in Eastern India and to clarify the phyloge- netic origin and virological characteristics of the recently identifi ed genotype C in this region. METHODS: Genotype determination, T1762/A1764 mutation in the basal core promoter (BCP) and A1896 mutation in the precore region of 230 subjects were de- termined by restriction fragment length polymorphism method (RFLP) and the result was confi rmed by direct sequencing. RESULTS: The predominant genotypes D (HBV/D) and A (HBV/A) were detected in 131/230 (57%) and 57/230 (25%) samples. In addition, genotype C (HBV/C) was detected in 42/230 (18%) isolates. Surface gene region was sequenced from 45 isolates (27 HBV/C, 9 HBV/A and 9 HBV/D). Phylogenetic analysis revealed that all of the HBV/C sequences clustered with South East Asian subgenotype (HBV/Cs). The sequence data showed re- markable similarity with a Thai strain (AF068756) (99.5% ± 0.4% nucleotide identities) in 90% of the genotype C strains analyzed. T1762/A1764 mutation in BCP re- gion, associated with high ALT was signifi cantly higher in HBeAg negative isolates than HBeAg positive isolates. Frequency of A1896 mutation leading to HBeAg negativ- ity was low.CONCLUSION: The present study reports the genotypic distribution and the characteristics of partial genome sequences of HBV/C isolates from Eastern India. Low genetic diversity and confi nement of HBV/C in Eastern India possibly indicate a recent, limited, spread in this region. Genotype C with T1762/A1764 mutation has been reported to increase the risk for hepatocellular car- cinoma; therefore genotype C carriers in Eastern India should be carefully monitored.
文摘Hepatitis C virus(HCV) is an emerging infection worldwide and the numbers of persons infected are increasing every year. Poor blood transfusion methods along with unsafe injection practices are potential sources for the rapid spread of infection. Early detection of HCV is the need of the hour especially in high riskgroup population as these individuals are severely immunocompromised. Enzyme Immunoassays are the most common detection techniques but they provide no evidence of active viremia or identification of infected individuals in the antibody-negative phase and their efficacy is limited in individuals within high risk group population. Molecular virological techniques have an important role in detecting active infection with utmost specificity and sensitivity. Technologies for assessment of HCV antibody and RNA levels have improved remarkably, as well as our understanding of how to best use these tests in patient management. This review aims to give an overview of the different serological and molecular methods employed in detecting HCV infection used nowadays. Additionally, the review gives an insight in the new molecular techniques that are being developed to improve the detection techniques particularly in High Risk Group population who are severely immunocompromised.
文摘Shared routes of transmission lead to frequent human immunodeficiency virus(HIV)-hepatitis B virus(HBV) coinfection in a host which results in about 10% of HIV positive individuals to have chronic hepatitis B infection worldwide. In post-antiretroviral therapy era, liverdiseases have emerged as the leading cause of morbidity and mortality in HIV-infected individuals and HBV coinfection have become the major health issue among this population particularly from the regions with endemic HBV infection. In setting of HIV-HBV co-infection, HIV significantly impacts the natural history of HBV infection, its disease profile and the treatment outcome in negative manner. Moreover, the epidemiological pattern of HBV infection and the diversity in HBV genome(genotypic and phenotypic) are also varied in HIV co-infected subjects as compared to HBV mono-infected individuals. Several reports on the abovementioned issues are available from developed parts of the world as well as from sub-Saharan African countries. In contrast, most of these research areas remained unexplored in India despite having considerable burden of HIV and HBV infections. This review discusses present knowledge from the studies on HIV-HBV co-infection in India and relevant reports from different parts of the world. Issues needed for the future research relevant to HIV-HBV co-infection in India are also highlighted here, including a call for further investigations on this field of study.
基金Supported by Fellowship and funds from University Grants Commission(UGC)Min.of Human Resource and Development,Govt.of India and Defence Research&Development Organi-zation(DRDO)(DRDO)+2 种基金Min.of Defence,Govt.of India(to Sibnarayan Datta)Indian Council of Medical Research(ICMR)Ministry of Health and Family Welfare(MoH FW)(to Runu Chakravarty)
文摘AIM To investigate the role of subgenotype specific RNA secondary structure in the compartment specific selection of hepatitis B virus(HBV)immune escape mutations.METHODS This study was based on the analysis of the specific observation of HBV subgenotype A1 in the serum/plasma,while subgenotype A2 with G145R mutation in the peripheral blood leukocytes(PBLs).Genetic variability found among the two subgenotypes was used for prediction and comparison of the full length pregenomic RNA(pgRNA)secondary structure and base pairings.RNA secondary structures were predicted for 37℃using the Vienna RNA fold server,using default parameters.Visualization and detailed analysis was done using RNA shapes program.RESULTS In this analysis,using similar algorithm and conditions,entirely different pgRNA secondary structures for subgenotype A1 and subgenotype A2 were predicted,suggesting different base pairing patterns within the two subgenotypes of genotype A,specifically,in the HBV genetic region encoding the major hydrophilic loop.We observed that for subgenotype A1 specific pgRNA,nucleotide 358U base paired with 1738A and nucleotide 587G base paired with 607C.However in sharp contrast,in subgenotype A2 specific pgRNA,nucleotide 358U was opposite to nucleotide 588G,while 587G was opposite to 359U,hence precluding correct base pairing and thereby lesser stability of the stem structure.When the nucleotides at 358U and 587G were replaced with 358C and 587A respectively(as observed specifically in the PBL associated A2 sequences),these nucleotides base paired correctly with 588G and 359U,respectively.CONCLUSION The results of this study show that compartment specific mutations are associated with HBV subgenotype specific alterations in base pairing of the pgRNA,leading to compartment specific selection and preponderance of specific HBV subgenotype with unique mutational pattern.
文摘Human immunodeficiency virus(HIV) infection among men who have sex with men(MSM) has increased to a drastic proportion throughout India in the last couple of years due to a lack of productive identification and management framework. In apprehension of social disgrace these men attempt to live a normal hetero conjugal life and, in the process, act as a bridge in spreading the virus to their women partners. In this case report we have highlighted two cases which clearly distinguished the adequacy of HIV treatment among MSM when they are diagnosed during early or late phases of infection. An intensive and ample counseling to comprehend the psychology and sexual behavior of these men was found to be critically important in both the cases. Our study, which is actually the first of its kind, recorded and documented evidence of HIV infected MSM from Eastern India and renders a ray of hope among this marginally isolated group to comprehend the challenges and health risks faced by the MSM population. It also provides a format for the medical practitioners here in managing and treating related cases.
基金grants partly from West Bengal State AIDS Prevention & Control Society, Kolkata and partly by Indian Council of Medical Research, New Delhi. Partha Kumar Chandra received a research associateship from West Bengal State AIDS Prevention & Control Society, Kolkata. Arup Banerjee received a senior research fellowship from Indian Council of Medical Research New Delhi Sibnarayan Datta received a senior research fellowship from University Grants Commission, New Delhi
文摘AIM: To evaluate the prevalence of markers of hepatitis B virus (HBV) and hepatitis C virus (HCV) and human immunodeficiency virus (HIV) among blood donors in Kolkata, Eastern India for two consecutive years and to conduct a pilot study to explore the presence of HBV DNA among hepatitis B surface antigen (HBsAg) negative but anti-HBc positive blood donors. METHODS: Seroprevalence of HBsAg, anti-HCV and anti-HIV was studied among 113 051 and 106 695 voluntary blood donors screened in 2004 and 2005, respectively. Moreover, a pilot study on 1027 HBsAg negative donors was carried out for evaluating the presence of HBV DNA by PCR on HBsAg negative/anti- HBc positive donors. RESULTS: A statistically significant increase in the prevalence of HBV (1448 vs 1768, P < 0.001), HIV (262 vs 374, P < 0.001), HCV (314 vs 372, P = 0.003) and syphilis (772 vs 853, P = 0.001) infections was noted among blood donors of Kolkata West Bengal in 2005 as compared to 2004. Moreover, the exploratory study on 1027 HBsAg negative donors revealed that 188 (18.3%)of them were anti-HBc positive out of which 21% were positive for HBV DNA. CONCLUSION: The findings of this study underscore the significantly increasing endemicity of hepatitis viruses, syphilis and HIV among the voluntary blood donors of our community. The pilot study indicates a high rate of prevalence of HBV DNA among HBsAg negative/anti-HBc positive donors and thus emphasizes the need for a more sensitive and stringent screening algorithm for blood donations.
文摘Objective:To investigate the outbreak of unknown fever at Siliguri town,Darjeeling District on request from the State Health Department,Government of West Bengal.Methods: Investigations were made to the affected wards,Sub Divisional Hospital and the nursing homes of Siliguri Town.Duration of illness was 3-5 days.Interesting observations were made in some cases which had gastrointestinal disorders with high serum glutamate pyruvate transaminase(SGPT) and serum glutamic oxaloacetic transaminase(SCOT) levels.A total of 69 blood samples and 7 throat swabs(in Minimum Essential Media) were collected and brought to the ICMR Virus Unit, Kolkata for analysis.Mosquitoes from different affected areas were collected for the identification of the definite vector.Results:Amongst the 69 blood samples,42(60.86%) were positive to IgM antibody against dengue virus by Mac enzyme-linked immunosorbent assay(ELISA) test.No IgM antibody to Japanese encephalitis virus was detected among the collected blood samples.Based on the clinical symptoms,presence of IgM antibody to dengue virus and identification of Aedes mosquito,it amply proves that,the illness of those cases were due to dengue virus infection. Conclusions:Based on clinical-epidemiological observations of the investigations the possibility of a communicable disease of viral origin,the detection of IgM antibody and the identification of Aedes egypti,and the potential circulation of denge virus in Siliguri town for the first time were all suggested.
