Status of hepatitis B infection - a decade after hepatitis B vaccination of susceptible Nicobarese, an indigenous tribe of Andaman & Nicobar (A&N) islands with high hepatitis B endemicity.

Background & objectives: Andaman and Nicobar Islands of India, home to six primitive tribes, constituting about 10 per cent of the total population of these Islands have been detected with high endemicity of hepatitis B infection. During 2000, a total of 936 individuals ≤ 45 yr, negative for hepatitis B surface antigen (HBsAg) and antibody anti-HBs were vaccinated with three doses of a recombinant DNA hepatitis B vaccine in two villages of Car Nicobar Islands. the present study was undertaken to evaluate the impact of the hepatitis B vaccination with respect to the persistence of antibodies and incidence of new infections, prevalence of surface gene mutations among the Nicobarese community in the two villages ten years after hepatitis B vaccination. Methods: Follow up samples were collected from 211 individuals who had received three doses of vaccine ten years back and from a control group of 515 non-vaccinated individuals. The HBsAg, anti-HBs and anti-HBc assay results were compared among vaccinated and non-vaccinated groups. HBV DNA was extracted and sequenced from all the samples for detection of mutation. Genotyping and serotyping of the viruses were performed. Results: The results showed that 85.3 per cent of the vaccinated persons retained protective level of antibodies and among the non-vaccinated individuals, 54.2 per cent showed presence of anti-HBs indicating an exposure to the infection. The overall HBsAg positivity among the studies Nicobarese individuals was reduced to 7.4 per cent after 10 years of vaccination. Anti-HBc was positive in 60.6 and 57 per cent among the vaccinated and non-vaccinated individuals, respectively. Overall breakthrough infection of 8.5 per cent was detected among the vaccinated individuals. the predominant genotype and serotype circulating among these tribal populations were D and ayw3, respectively. Interpretation & conclusions: the results of this study showed an overall reduction in the pool of HBsAg carriers because of the vaccination which helped in reducing the HBsAg carrier rate among the non-vaccinated also, probably due to an increase in herd immunity and reduction in the source of infection. Further studies need to be done to evaluate long term benefits of hepatitis B vaccination among these tribes.

Impact of hepatitis B immunization among the Nicobarese tribe - antibody titres & seroprotection five years after vaccination.

Background & objectives: A total of 237 Nicobarese subjects who had received hepatitis B vaccination as part of mass vaccination project during 2000-2001 were screened for anti-HBsAg titres by quantitative ELISA five years after vaccination. Methods: Anti-HBsAg antibody was estimated using quantitative ELISA. Proportion of the subjects with protective levels of antibody and geometric mean antibody titres were calculated. Results: Among the 237 study subjects, 213 had received three doses of vaccine, 17 had received two doses and seven had received one dose. The geometric mean titres of anti-HBs antibodies were 201.7, 31.9 and 23.1 mIU/ml among those who received three, two and one dose of vaccine, respectively. Among those who received three doses of vaccination, 85.9 per cent had anti-HBs antibody levels of 10 mIU/ml or more, indicating seroprotection. The difference in the seroprotection rates among those who received three doses of vaccination (85.9%) and those who received less than three doses (58.3%) was significant. Seroprotection rates one month after the first, second and third dose of vaccination were 49.1, 86.9 and 96.7 per cent, respectively. It then declined to 89 per cent by the end of the second year and to 85.5 per cent by the end of the third year, but there was no decline thereafter. Interpretation & conclusions: Seroprotection rate reached at the maximum one month after the third dose of HBV vaccine. Although about 15 per cent of the vaccinated persons lost seroprotection by the end of the third year, no further loss in seroprotection was observed between the third year and the fifth year.

Antidepressant activity of hyperforin conjugates of the St. John's wort, Hypericum perforatum Linn.: an experimental study.

Nine extracts of H. perforatum, containing hyperforin in conjugated forms, but devoid of free hyperforin and adhyperforin, were subjected to antidepressant screening using the forced swim test (FST). The observed activity was compared with that of SJW extracts containing hyperforin and adhyperforin (in free form). Results indicate that hyperforin conjugates exhibit significant antidepressant activity as evidenced by the reduced immobility period in the FST in rats.

Effect of herbo-mineral formulation EHb in experimental anaemia in rodents.

EHb-a herbo-mineral formulations of iron (ferrous form) produced a significantly higher and dose dependent increase in the haemoglobin level, as compared to Fefol (a non-complex-chelated iron preparation). Also, EHb did not produce any overt toxicity or gastric irritation at these dose levels. The results suggest that EHb can be of a better choice in the treatment of anaemia than any other commercially available chelated iron preparations.

Antioxidant activity of tannoid principles of Emblica officinalis (amla) in chronic stress induced changes in rat brain.

Effect of tannoid principles emblicanin A, emblicanin B, punigluconin, and pedunculagin of E. officinalis was assessed on chronic unpredictable footshock-induced stress-induced perturbations in oxidative free radical scavanging enzymes in rat brain frontal cortex and striatum. Chronic stress, administered over a period of 21 days, induced significant increase in rat brain frontal cortical and striatal superoxide dismutase (SOD) activity, concomitant with significant reduction in catalase (CAT) and glutathione peroxidase (GPX) activity. The changes in the enzyme activities was accompanied by an increase in lipid peroxidation, in terms of augmented thiobarbituric acid-reactive products. Administration of Emblica tannoids (10 and 20 mg, po) for 21 days, concomitant with the stress procedure, induced a dose-related alteration in the stress effects. Thus, a tendency towards normalization of the activities of SOD, CAT and GPX was noted in both the brain areas, together, with reduction in lipid peroxidation. The results indicate that the reported antistress rasayana activity of E. officinalis may be, at least partly due to its tendency to normalize stress-induced perturbations in oxidative free radical scavenging activity, in view of the postulate that several stress-induced diseases, including the process of aging, may be related to accumulation of oxidative free radicals in different tissues.

Antioxidant activity of active tannoid principles of Emblica officinalis (amla).

The antioxidant activity of tannoid active principles of E. officinalis consisting of emblicanin A (37%), emblicanin B (33%), punigluconin (12%) and pedunculagin (14%), was investigated on the basis of their effects on rat brain frontal cortical and striatal concentrations of the oxidative free radical scavenging enzymes, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX), and lipid peroxidation, in terms of thiobarbituric acid-reactive products. The results were compared with effects induced by deprenyl, a selective monoamine oxidase (MAO) B inhibitor with well documented antioxidant activity. The active tannoids of E. officinalis (EOT), administered in the doses of 5 and 10 mg/kg, i.p., and deprenyl (2 mg/kg, i.p.), induced an increase in both frontal cortical and striatal SOD, CAT and GPX activity, with concomitant decrease in lipid peroxidation in these brain areas when administered once daily for 7 days. Acute single administration of EOT and deprenyl had insignificant effects. The results also indicate that the antioxidant activity of E. officinalis may reside in the tannoids of the fruits of the plant, which have vitamin C-like properties, rather than vitamin C itself.

Antioxidant activity of glycowithanolides from Withania somnifera.

Antioxidant activity of active principles of Withania somnifera, consisting of equimolar concentrations of sitoindosides VII-X and withaferin A, was investigated for their effects on rat brain frontal cortical and striatal concentrations of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX). Results were compared with effects induced by deprenyl, an agent with well documented antioxidant activity. Active glycowithanolides of W. somnifera (WSG) (10 and 20 mg/kg, i.p.), administered once daily for 21 days, induced a dose-related increase in SOD, CAT and GPX activity in frontal cortex and striatum, which was statistically significant on days 14 and 21, except with the lower dose of WSG on GPX activity, where the effect was evident only on day 21. The data were comparable to those induced by deprenyl (2 mg/kg/day, i.p.) with respect to SOD, CAT and GPX activities, which were evident by day 14. These findings are consistent with the therapeutic use of W. somnifera as an Ayurvedic rasayana and medhyarasayana. Antioxidant effect of active principles of W. somnifera may explain, at least in part, the reported antistress, immunomodulatory, cognition-facilitating, anti-inflammatory and anti-aging effects produced by them in experimental animals, and in clinical situations.