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Review GB virus infection: a silent anti-HIV panacea within? 2008
Shankar EM, Solomon SS, Vignesh R, Murugavel KG, Sundaram M, Solomon S, Balakrishnan P, Kumarasamy N. · YRG Centre for AIDS Research and Education (YRG CARE), Voluntary Health Services Hospital Campus, IT Corridor, Taramani, Chennai 600 113, India. · Trans R Soc Trop Med Hyg. · Pubmed #18513775 No free full text.
Abstract: The GB virus (GBV)/hepatitis G virus is a member of the Flaviviridae family and belongs to the hepatitis group of viruses transmitted parenterally, common among intravenous drug users. The strong association between GBV and HIV infection suggests that the two viruses may share similar epidemiological and transmission features. GBV infection is widely believed to prolong HIV disease progression as well as decreasing the HIV viral load and increasing the CD4(+) T-cell level. GBV-driven anti-E2 antibodies have been shown to inhibit HIV replication in vitro. Preliminary studies also suggest that GBV infection of peripheral blood mononuclear cells leads to increased production of beta-chemokines, which may explain the in vitro inhibitory effects and warrants further studies. With sufficient knowledge of resistance patterns studied in tropical south India, researchers are now keen to study the competitive interactions between GBV-induced chemokines and HIV ligands to bind CCR5.
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Clinical Conference Comparative efficacy of two dosages of recombinant hepatitis B vaccine in healthy adolescents in India. 2007
Velu V, Nandakumar S, Shanmugam S, Shankar EM, Thangavel S, Kulkarni PS, Thyagarajan SP. · Department of Microbiology, Dr ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani, Chennai, India. · Pediatr Infect Dis J. · Pubmed #17984812 No free full text.
Abstract: BACKGROUND: Inclusion of hepatitis B vaccine in the Universal Programme of Immunization of all Asian and African countries is hampered by the economic burden on the health budget because of the cost of hepatitis B vaccines. Here we evaluated the immunogenicity, safety, efficacy, and the persistence of antibody to hepatitis B surface antigen (anti-HBs) titers of a new and a low cost recombinant hepatitis B vaccine GeneVac B, with 2 different dosages in healthy adolescents in India. METHODS: GeneVac-B, a recombinant hepatitis B vaccine (Serum Institute of India, Pune, India), was administered in 10 or 20 microg dose intramuscularly to 2 groups of 100 healthy school-going adolescents at 0-, 1-, and 6-month intervals, who were followed up for 1 year. Group I received 20 mug doses whereas Group II received 10 mug doses. Blood samples were collected 1 month after each dose and 1 year after the third dose. The anti-HBs titers were assayed using commercially available kits to assess the immunogenicity of the 2 dosage schedules. Safety studies were also carried out. RESULTS: The geometric mean titer value of the anti-HBs titer 1 month after the third dose was 2629 (mlU/mL) in Group I and 1373 mlU/mL for Group II subjects. One year after the third dose, the persistence of anti-HBs in those who had received 20 mug was 2262 mlU/mL whereas it was 1039 mlU/mL in the group receiving 10 microg doses. All the subjects in both the groups were seroprotected at 1 year after vaccination. None of the vaccinees exhibited serious adverse reactions throughout the study period. CONCLUSIONS: The study demonstrated the immunogenicity of the recombinant hepatitis B vaccine, and confirms that the 0.5 mL (10 microg) dose of GeneVac B can be administered with satisfactory safety and immunogenicity to adolescents up to 19 years of age, reducing the cost to less than U.S. $1.00 per dose making it acceptable for the Universal Programme of Immunization of developing and under developed countries.
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Article Low frequency of precore mutants in anti-hepatitis B e antigen positive subjects with chronic hepatitis B virus infection in Chennai, Southern India. free! 2008
Shanmugam S, Velu V, Nandakumar S, Madhavan V, Shanmugasundaram U, Shankar EM, Murugavel KG, Balakrishnan P, Kumarasamy N, Solomon S, Thyagarajan SP. · YR Gaitonde Centre for AIDS Research and Education, Voluntary Health Services, Chennai 600 113, India. · J Microbiol Biotechnol. · Pubmed #18955826 links to free full text
Abstract: The natural course of chronic hepatitis B (CH-B) virus infection is reportedly variable, and the long-term outcomes in hepatitis B e antigen (HBeAg)-negative chronic hepatitis B infection are distinct from HBeAg-positive chronic hepatitis. However, the molecular virological factors that contribute to the progression of liver disease in the south Indian setting remain largely unclear. We prospectively studied 679 consecutive patients for HBsAg, HBeAg, anti-HBeAg, and HBV DNA by qualitative PCR. Randomly selected samples were subjected to bidirectional sequencing to reveal core/precore variants. Of the total 679 chronic HBV cases investigated, 23% (154/679) were replicative HBV carriers. Furthermore, amongst the 560 HBV DNA samples analyzed, 26% (146/560) were viremic. Among the 154 HBeAg positive cases, HBV DNA was positive in 118 cases (77%), significantly (p<0.001) higher than the anti-HBe positive (7%) (28/406) cases. Significant increase in liver disease (p<0.01) with ALT enzyme elevation (p<0.001) was observed in both HBe and anti-HBe viremic cases. Interestingly, low frequencies of mutations were seen in the precore region of the HBV strains studied. HBV precore and core promoter variants were less often detected in subjects with "e" negative chronic HBV infection and, therefore, may not have a prognostic role in determining liver disease sequelae in this part of tropical India.
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Article Alpha-fetoprotein as a tumor marker in hepatocellular carcinoma: investigations in south Indian subjects with hepatotropic virus and aflatoxin etiologies. 2008
Murugavel KG, Mathews S, Jayanthi V, Shankar EM, Hari R, Surendran R, Vengatesan A, Raghuram K, Rajasambandam P, Murali A, Srinivas U, Palaniswamy KR, Pugazhendhi T, Thyagarajan SP. · Infectious Diseases Laboratory, YRG Centre for AIDS Research & Education, VHS Hospital Campus, Taramani, Chennai 600 113, India. · Int J Infect Dis. · Pubmed #18658001 No free full text.
Abstract: OBJECTIVES: The prevalence of hepatitis B virus (HBV) is reportedly the main cause of hepatocellular carcinoma (HCC) in India, where hepatitis C virus (HCV)-associated HCC is believed to be relatively less prevalent. We verified the usefulness of alpha-fetoprotein (AFP) as a tumor marker and analyzed the influence of viral etiology on AFP levels in HCC. METHODS: Of a total of 1012 cases with liver disease, 202 were investigated for the presence of AFP (142 HCC cases, 30 cirrhosis cases, and 30 chronic liver disease (CLD) cases). In addition, serum samples from 30 healthy patients, 30 hepatitis B surface antigen (HBsAg) carriers, and 30 acute viral hepatitis cases were included as controls. AFP was quantitatively determined using a commercial ELISA (Quorum Diagnostics, Canada). Out of the 142 HCC cases screened for AFP, aflatoxin B1 (AFB1) detection was carried out in 38 HCC cases using an in-house immunoperoxidase test. RESULTS: In HBV and HCV co-infected HCC cases, the AFP positivity was 85.7%. In HBV alone-associated HCC, the positivity was 62.9%, and 54.5% of AFB1 positive HCC cases showed AFP positivity. In HBV and HCV negative HCC cases, the positivity was 20.5%, and in HCV-associated HCC it was 17.6%. The HBV/HCV co-infected group and HBV alone positive HCC cases had significantly elevated levels of AFP. When AFP positivity was analyzed based on the marker profile of HBV, 89.7% of AFP positive cases were HBV-DNA positive. CONCLUSIONS: The overall positivity pattern of AFP in HCC does indicate that higher levels of AFP are observed with hepatitis virus positivity, especially with HBV. Further studies must be carried out to correlate the serum levels of AFP with the size, number, and degree of differentiation of HCC nodules.
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Article Relationship between T-lymphocyte cytokine levels and sero-response to hepatitis B vaccines. free! 2008
Velu V, Saravanan S, Nandakumar S, Shankar EM, Vengatesan A, Jadhav SS, Kulkarni PS, Thyagarajan SP. · Department of Medical Microbiology, University of Madras, Chennai 600113, India. · World J Gastroenterol. · Pubmed #18567083 links to free full text
Abstract: AIM: To investigate the cellular defects by analyzing the (Th1/Th2) cytokine levels in vaccine responders and non-responders. METHODS: Peripheral blood mononuclear cell (PBMC) from responders and non-responders were stimulated with or with out recombinant HBsAg or PHA. Broad spectrum of cytokines viz (Th1) IFN-gamma, IL-2, TNF-alpha, IL-12 and (Th2) IL-10, IL-4 were measured after in vitro stimulation with recombinant HBsAg and were compared with respective antibody titers. RESULTS: A significant decrease (P = 0.001) in Th1 and Th2 cytokines namely, IL-2, INF-gamma, TNF-alpha and IL-10 in non-responders was observed. The level of IL-4 was not significant between the three groups. Furthermore, despite a strong Th1 and Th2 cytokine response, the level of IL-12 was elevated in high-responders compared to other groups (P = 0.001) and demonstrated a positive correlation with anti-HBs titers and Th1 cytokine response. CONCLUSION: Our findings suggest that unresponsiveness to recombinant hepatitis B vaccines (rHB) is multifactorial, including specific failure of antigen presentation or the lack of both T helper Th1 and Th2 response.
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Article Seroprevalence of hepatitis delta virus infection among subjects with underlying hepatic diseases in Chennai, southern India. 2008
Saravanan S, Velu V, Kumarasamy N, Shankar EM, Nandakumar S, Murugavel KG, Balakrishnan P, Solomon S, Thyagarajan SP. · Indian Council of Medical Research Referral Centre for Chronic Hepatitis and Molecular Virology, Department of Microbiology, University of Madras, Chennai 600 113, India. · Trans R Soc Trop Med Hyg. · Pubmed #18556033 No free full text.
Abstract: Four hundred million people are carriers of hepatitis B virus (HBV) worldwide and approximately 5% of these are reportedly positive for hepatitis delta virus (HDV). Several reports indicate a declining trend in the occurrence of HDV infection in the north of tropical India. To our knowledge, no study has been conducted to evaluate whether a similar epidemiological change is occurring in southern India. Therefore we evaluated the seroprevalence of HDV among 153 individuals with HBV-related liver diseases in Chennai, and assessed any change in epidemiological pattern by comparing the results with seroprevalence figures reported previously. Of the 153 patients screened, nine (5.9%) were reactive to anti-delta antibodies, six (3.9%) presented an evidence of past infection (IgG anti-delta positive) and three (2.0%) showed anti-HDV IgM, suggestive of recent HDV infection. Alanine transaminase elevation was not significant in HDV-associated infection compared with HBV alone-infected acute viral hepatitis (AVH) (P=0.82) and chronic liver disease (P=0.77) patients. The anti-HDV positivity in AVH was considerably low (6.6%), compared with previous Indian reports varying from 10.7% to >30%. HDV infection was relatively low and seems to play a minor determining factor of liver diseases in the tropical south Indian population.
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Article The prevalence of hepatitis B virus and hepatitis C virus infection among patients with chronic liver disease in South India. 2008
Saravanan S, Velu V, Kumarasamy N, Shankar EM, Nandakumar S, Murugavel KG, Balakrishnan P, Solomon SS, Solomon S, Thyagarajan SP. · Department of Microbiology, Faculty of Medicine, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Chennai 600 113, India. · Int J Infect Dis. · Pubmed #18455943 No free full text.
Abstract: OBJECTIVE: Determining the identity of hepatitis C virus (HCV) genotypes in liver disease has key implications for ascertaining the duration of antiviral therapy and disease prognosis. We investigated the presence of various genotypes of HCV among 69 chronic liver diseased (CLD) patients with chronic HCV infection. METHODS: Sixty-nine consecutive subjects with underlying chronic hepatitis (n=28), cirrhosis (n=35), and hepatocellular carcinoma (n=6), diagnosed by clinical, biochemical, and histological means, were studied. Hepatitis B virus (HBV) and HCV diagnostic markers were used. HCV-RNA was extracted from sera of HCV-infected subjects and subsequently the HCV genotypes were determined using a commercial line probe assay (Inno-LiPA HCV II). RESULTS: Of the 69 CLD cases screened for possible markers of HBV and HCV infection, 39 (57%) were positive for HBV and 30 (43%) were HCV infected. The overall HCV-RNA positivity was 77% (23/30). Of these, the majority were genotype 1b (13/23, 57%), followed by 1a (6/23, 26%), mixed genotypes 3 and 4(3/23, 13%), and mixed pattern of 1a, 1b, and 4 (1/23, 4.3%). The genotype 1b infected subjects demonstrated significantly elevated transaminase (ALT) levels (p<0.05) as compared with the other non-1b HCV genotypes. CONCLUSIONS: The predominance of HCV genotype 1b among CLD patients could pose a major challenge for the efficient management of HCV disease and the development of effective therapeutic interventions in peninsular India.
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Article Transmission of "a" determinant variants of hepatitis B virus in immunized babies born to HBsAg carrier mothers. free! 2008
Velu V, Saravanan S, Nandakumar S, Dhevahi E, Shankar EM, Murugavel KG, Kumarasamy T, Thyagarajan SP. · Department of Medical Microbiology, Dr ALM Post Graduate Institute of Basic Medical Sciences and National Referral Centre for Viral Hepatitis, University of Madras, Chennai, India. · Jpn J Infect Dis. · Pubmed #18219140 links to free full text
Abstract: Hepatitis B virus (HBV) surface antigen mutations may lead to immune escape and eventually cause failure of immunization. In this report, we identified immune escape variants in immunized babies born to hepatitis B surface antigen (HBsAg) carrier mothers. A total of 68 babies were followed up for 2 years after the full course of vaccination; 2.9% (2/68) of babies were found to be infected with the variant HBV in spite of preexisting antibody to surface antigen (anti-HBs) at 24 months post immunization. Both infants were positive for HBV-DNA; sequencing results of the "a" determinant region of the surface gene revealed that both babies had point mutations at a different nucleotide position resulting in various amino acid substitutions. In addition, an intriguing variant having an addition-deletion mutation was observed in one of the babies. This is the first report to show the addition-deletion variant of HBV in India. However, the immunological significance of the above HBV variants needs to be further elucidated.
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Article Prevalence of aflatoxin B1 in liver biopsies of proven hepatocellular carcinoma in India determined by an in-house immunoperoxidase test. free! 2007
Murugavel KG, Naranatt PP, Shankar EM, Mathews S, Raghuram K, Rajasambandam P, Jayanthi V, Surendran R, Murali A, Srinivas U, Palaniswamy KR, Srikumari D, Thyagarajan SP. · Department of Microbiology, Faculty of Medicine, Dr ALM PG Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai, India. · J Med Microbiol. · Pubmed #17965344 links to free full text
Abstract: Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer-related death in the world. The incidence of HCC in India is reportedly low and varies from 0.2 to 1.9 %. Aflatoxins, secondary metabolites produced by Aspergillus flavus and Aspergillus parasiticus, are potent human carcinogens implicated in HCC. The prevalence of aflatoxin B1 (AFB1) as co-carcinogen was analysed using an in-house immunoperoxidase test in 31 liver biopsies and 7 liver-resection specimens from histopathologically proven HCC, and in 15 liver biopsies from cirrhosis patients (control group). Serum was tested for hepatitis B and C serological markers using commercial assays, and for AFB1 using an in-house ELISA with a sensitivity of approximately 1 ng ml(-1) for AFB1. In spite of positive AFB1 immunostaining in HCC cases, all serum specimens, from both HCC and the control groups, were AFB1-negative. There were 18 (58.1 %) HCC cases that revealed AFB1 in liver biopsies; 68.8 % (n=11) of non-B non-C hepatitis cases with HCC and 46.1 % (n=6) of the hepatitis B surface-antigen-positive subjects were positive for AFB1. Out of the two hepatitis B/hepatitis C virus co-infected cases, one was positive for AFB1. Of seven tumour-resection samples, six were positive for AFB1. Only one case revealed AFB1 in the non-tumour area of the resected material. Thus AFB1 staining was significantly associated with tumour tissue (P=0.03). Aflatoxins proved to have a significant association with HCC in this peninsular part of the subcontinent. The impact seems to be a cumulative process, as revealed by the AFB1 deposits in HCC liver tissue, even though the serum levels were undetectable.
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