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Biomedical subjects

S Chakraborty

Publications and source records attributed to S Chakraborty.

At least 181 records · Page 10Linked to original sources

The influence of testosterone on brain cholesterol.

Male sex hormone testosterone propionate induces esterification of brain cholesterol. Esterified cholesterol is absent in the brain of female rats, treatment with male hormone induces esterification. In castrated male rats the esterified cholesterol from brain disappears, whereas supplementation to those animals with testosterone helps in the re-appearance of esterified cholesterol.

Animals↗

Proliferative activity in invasive breast carcinoma: a comprehensive comparison of MIB-1 immunocytochemical staining in aspiration biopsies to image analytic, flow cytometric and histologic parameters.

OBJECTIVE: To use MIB-1 antibody to assess proliferative activity in fine needle aspiration (FNA) samples of invasive breast carcinoma and compare these results to multiple other measures of proliferative activity. STUDY DESIGN: FNA slides from 62 patients with invasive breast carcinoma were subjected to staining with MIB-1. Quantitative MIB-1 values were compared to image analytic proliferative fractions (IPF) obtained from the same FNAs. MIB-1 values were also compared to flow cytometric S-phase fractions (SPF) and S + G2/M-phase fractions (FPF) and to histologic assessment of mitotic count (MC) in resected tumors. RESULTS: MIB-1 values, IPF, SPF, FPF and MC were suitable for evaluation in 55, 53, 50, 50 and 56 cases, respectively. MIB-1 values showed good correlation with IPF in FNAs (correlation coefficient = .57, P <.00001). MIB-1 values also showed correlation with SPF (correlation coefficient =.447, P = .003), FPF (correlation coefficient = .325, P = .023) and MC (correlation coefficient = .402, P = .01) in resected tumors. CONCLUSION: This study supports the use of MIB-1 values obtained from FNA samples for assessment of proliferative activity in invasive breast carcinoma, based on correlation of these values with multiple other parameters of proliferative activity. Assessment of these values can play a role in predicting prognosis and in selecting patients with invasive carcinoma of the breast for preoperative or adjuvant chemotherapy.

Adenocarcinoma↗

Pathogenic vibrios in the natural aquatic environment.

In recent years, members belonging to the genus Vibrio of the family Vibrionaceae have acquired increasing importance because of the association of several of its members with human disease. The most feared of the Vibrio species is Vibrio cholerae, the causative agent of cholera, a devastating disease of global significance. Other important vibrios of medical importance are V. parahemolyticus, V. vulnificus, V. mimicus, and to a lesser extent V. fluvialis, V. furnissii, V. hollisae, and V. damsela. Recent studies have also implicated V. alginolyticus and V. metschnikovii in human disease, although their complete significance has not yet been established. The virulence of all medically important vibrios is aided by a variety of traits that help breach human defenses. In this review, we provide an overview of the environmental distribution of the pathogenic vibrios and the important virulence traits that enable them to cause disease.

Ecology↗

Vibrio cholerae O139 in Calcutta, 1992-1998: incidence, antibiograms, and genotypes.

We report results of surveillance for cholera caused by Vibrio cholerae O139 from September 1992, when it was first identified, to December 1998. V. cholerae O139 dominated as the causative agent of cholera in Calcutta during 1992-93 and 1996- 97, while the O1 strains dominated during the rest of the period. Dramatic shifts in patterns of resistance to cotrimoxazole, neomycin, and streptomycin were observed. Molecular epidemiologic studies showed clonal diversity among the O139 strains and continuous emergence of new epidemic clones, reflected by changes in the structure, organization, and location of the CTX prophages in the V. cholerae O139

Base Sequence↗

Molecular evidence of clonal Vibrio parahaemolyticus pandemic strains.

The upsurge in worldwide incidence of Vibrio parahaemolyticus infection in the last 5 years has been attributed to the recent appearance of three serotypes with pandemic potential: O3:K6, O4:K68, and O1:K untypeable (KUT). Thirty-five strains of these serotypes, isolated from different countries over 4 years, were characterized by ribotyping and pulsed-field gel electrophoresis to determine their origin. The ribotypes of the strains of these serotypes were indistinguishable, except for a Japanese tdh- negative O3:K6 strain and a U.S. clinical O3:K6 isolate, which had slightly different profiles. The migration patterns of the NotI-digest of the total DNA of the strains were similar, and only slight variations were observed between the serotypes. By contrast, the O3:K6 and O1:KUT strains isolated before 1995 and strains of other serotypes had markedly different profiles. The O4:K68 and O1:KUT strains most likely originated from the pandemic O3:K6 clone.

Blotting, Southern↗

Early neonatal morbidity and mortality in a city based medical college nursery.

Early neonatal morbidity & mortality were studied in 7972 viable live born babies over one year period in Medical College, Calcutta. Early neonatal morbidity and mortality rate were 66.85 & 32.86 respectively. About 48% of Early neonatal deaths occurred in 1st 48 hours & 80% within first 72 hours of life. Early neonatal mortality rate per 1000 was maximum in babies born of a primi (43.03) and grand multiparous mother (103.89); maternal age less than 20 yrs. (44.15), and more than 30 yrs. (46.04) & in multiple pregnancy (142.85). It was highest in breech delivery (114.28) & with maternal disease like dribling (179), hypertension (146) & APH (116). Birth asphyxia contributed 65.26% of early neonatal deaths, followed by septicaemia (10.3%). Klebsiella was the most common (55%) organism.

Adult↗

Copper (II) induced radiosensitization of thymine.

An aqueous solution of thymine (2 x 10(-3) M, pH 5.6) was irradiated with 60Co gamma-rays in the absence and in the presence of CuSO4 (5 x 10(-4) M) under different conditions. In argon and N2O saturated solutions, the presence of CuSO4 increased the radiosensitivity of thymine to a greater extent, while the product distribution was changed. Thus in the presence of CuSO4 the formation of dimeric products was prevented and the yields of cis-thymine glycol and 5-hydroxymethyl uracil were greatly increased. The sensitized degradation was suggested to be due to the oxidation of the transient hydroxyl adducts of thymine by copper ions.

Cobalt Radioisotopes↗