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Kalyan Goswami

Publications and source records attributed to Kalyan Goswami.

6 recordsLinked to original sources

Potentiation of humoral immune response and activation of NF-kappaB pathway in lymphocytes in experimentally induced hyperthyroid rats.

This study explored the effect of hyperthyroid state on humoral immune response and NF-kappaB signaling in lymphocytes. Male Wistar rats were treated with l-thyroxin for four weeks. Animals were immunized with sheep red blood cells (SRBC) after three weeks of l-thyroxin treatment. After one week of immunization, serum anti-SRBC titer was measured and NF-kappaB signaling was studied in lymphocytes by Western blot analysis of p-IKB-alpha, IKB-alpha, and p65. These results were compared with that of control rats. Antibody response and density of p-IKB-alpha and p65 were significantly higher in l-thyroxin treated rats in comparison to controls. The antibody response was found to have significant correlation with density of p-IKB-alpha and p65. Our results indicate that NF-kappaB signaling pathway in lymphocytes is activated in hyperthyroid state which might play a role in potentiation of antibody response.

Animals↗

Oxidative changes and desialylation of serum proteins in hyperthyroidism.

BACKGROUND: Hyperthyroidism is associated with oxidative stress. Thyroid hormones are observed to influence the metabolism of plasma proteins. The present study was carried out to explore the level of sialic acid content and the oxidative changes of serum proteins in hyperthyroid subjects and matched healthy controls. METHODS: Blood was collected from 10 hyperthyroid patients and 10 age and sex matched healthy control subjects. The extent of carbonylation and desialylation of serum protein was estimated by dinitrophenylhydrazine and thiobarbituric acid methods, respectively. The protein cleavage and cross-linking were studied by separating serum protein in SDS-PAGE. The effects of in-vitro treatment of serum proteins with H(2)O(2) on the above-mentioned parameters were observed. RESULTS: The carbonylation was significantly higher and the sialic acid content was significantly lower in serum proteins of hyperthyroid cases in comparison to that of controls. Serum proteins were found to have increased levels of cleavage and cross-linking in hyperthyroid cases. The high molecular weight proteins were mostly cleaved. In-vitro treatment of serum proteins with H(2)O(2) led to similar changes. CONCLUSIONS: The study indicated that in hyperthyroidism, serum proteins undergo increased levels of oxidative changes leading to high turnover rate of blood proteins. A significant negative correlation between carbonylation and sialic acid content of serum proteins in hyperthyroidism and enhanced desialylation and carbonylation of serum proteins by in-vitro H(2)O(2) treatment suggest that oxidative stress can cause desialylation of serum glycoproteins.

Adult↗

Level of sialic acid residues in platelet proteins in diabetes, aging, and Hodgkin's lymphoma: a potential role of free radicals in desialylation.

The present study evaluated the levels of sialic acid and carbonylation in platelet proteins from diabetes, old age, and Hodgkin's lymphoma cases and explored the role of free radicals in desialylation. Sialic acid and carbonylation were estimated in platelet suspension obtained from 10 healthy adult control subjects, 20 elderly healthy persons, 20 cases with diabetes, and 10 with Hodgkin's lymphoma. The level of sialic acid residues in platelets was found to be significantly lower and the carbonylation of proteins was higher in old age, diabetes, and lymphoma cases in comparison to controls. The level of carbonylation correlated with desialylation in these cases. In vitro treatment of platelets with free radicals was found to cause desialylation and to increase the carbonyl content. Addition of 2-mercaptoethanol, an antioxidant, significantly attenuated the above effects. The study indicates the possible role of free radicals in desialylation of platelet proteins in the above clinical conditions.

Adult↗

Tumor necrosis factor-alpha microsatellite polymorphism association with rheumatoid arthritis in Indian patients.

BACKGROUND: Level of TNF-alpha increases significantly in synovial fluid of rheumatoid arthritis (RA) patients. It is proposed that tumor necrosis factor (TNF) microsatellite alleles may influence its expression and presumably can contribute to the disease severity. However, there is a lack of such study to predict any such association with RA in an Indian population. METHODS: In this study, we investigated the differential pattern of distribution of TNF microsatellite alleles in an Indian population and its association with RA. One hundred eighteen RA patients and 120 healthy individuals were genotyped for TNF microsatellite alleles using Genescan. Odds ratio was calculated to demonstrate the correlation between allelic distribution and clinical severity. RESULTS: The study shows that distribution of TNF microsatellite alleles in an Indian population is very different from other Asian Oriental and Western populations, except for some similarities with an Italian population. Frequency of microsatellite TNFd3 allele (9.24 vs. 3.85%, chi(2)=5.6, p < or =0.0179, OR=0.393, 95% CI=0.177-0.87) and more interestingly TNFd3 containing haplotypes has been found significantly reduced in patients. On the contrary, TNFb5 allele frequency increased in the patients (22.3 vs. 30.8%, chi(2)=4.4, p < or =0.036, OR=1.55, 95% CI=1.027-2.344) as compared to controls. Furthermore, significant increase in frequency of this allele in severe patients (22.3 vs. 33.8%, chi(2)=6.22, p < or =0.013, OR=1.78, 95% CI=1.132-2.798) along with the significant increase in haplotypes containing this allele supports the association of TNFb5 with disease severity. CONCLUSIONS: In an Indian population, TNFb5 may be considered as a risk factor, whereas TNFd3, unlike others, may be protective for RA.

Adult↗

Small group discussion followed by presentation as a revision exercise at the end of a teaching module in biochemistry.

BACKGROUND: We evaluated the effect of student-dominated small group discussion followed by faculty-moderated presentation as a revision exercise after completion of a teaching module in biochemistry. We assessed the understanding of graduate medical students on the topic and the gain in retention of information, if any, after 15 days. METHODS: Small group discussions involving 11-12 students in each group were conducted on 12 application-oriented problems in 'amino acid metabolism'. A group leader among the students helped to conduct the discussions. While two-thirds of the problems were taken up after the discussion during faculty- or student-moderated interactive presentations, the remaining were not. The effects on low-, medium- and high achievers were evaluated by a pre-test and post-test with multiple choice questions immediately after the session. A subjective feedback was also obtained. To test short-term memory, a post-test with the same multiple choice questions was conducted after 15 days. RESULTS: The exercise was effective and equally beneficial for low-, medium- and high achievers. The gain was maximum when faculty moderated the presentation session. The students' retention of their gain after 15 days was complete. All the students wanted more such sessions in future. CONCLUSION: Student-dominated small group discussion followed by a faculty-moderated presentation is an effective, revision exercise for undergraduate medical students.

Attitude of Health Personnel↗