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Biomedical subjects

N Bhattacharyya

Publications and source records attributed to N Bhattacharyya.

82 records · Page 5Linked to original sources
PubMed1986

Influence of inhibitors of poly(ADP-ribose)polymerase activity on X-ray and ultraviolet light induced killing and mutation in Chinese hamster V79 cells.

The effect of nicotinamide or benzamide, inhibitors of poly(ADP-ribose)polymerase activity, on X-ray and ultraviolet light induced killing of asynchronously dividing V79 Chinese hamster cells was to reduce the shoulder width of the survival curve; the rate of killing remaining unchanged and the yield of 8-azaguanine resistant mutants also remaining unaffected. However, when density inhibited cells were irradiated with X-rays or u.v. light, holding at this density allowed potentially lethal damage recovery (PLDR) to occur, enhancing survival. Inhibitors of poly(ADP-ribose)polymerase suppressed PLDR and also increased the yield of mutants. Thus the role of poly(ADP-ribose) in X-ray or u.v. induced killing and mutation was dependent on the condition of growth.

Animals↗
PubMed1985

Interaction of UV and N-methyl-N'-nitro-N-nitrosoguanidine: cytotoxicity and mutagenicity in V79 cells.

Killing and mutation by UV in the MNNG-exposed population of V79 cells, as well as by MNNG in the UV-irradiated population of these cells have been studied. It was observed that pretreatment with MNNG increased the killing and mutation by UV, whereas, pretreatment with UV had no effect upon killing and mutation by MNNG. The increase in sensitivity to UV due to pretreatment with MNNG was lost if UV exposure was delayed for 24 h after MNNG treatment.

Alkylating Agents↗
PubMed1984

UV non-mutable mutant from V-79 Chinese hamster cells.

To get an idea about the response of a living system, exposed to gradually increasing doses of a mutagen for several generations, a population of V-79 Chinese hamster cells was exposed repeatedly to gradually increasing doses of UV radiation. Each dose was followed by a variable period of growth for at least ten generations. After treatment the cells were not mutable by UV radiation, though MNNG was capable of producing mutations with the same efficiency as in the untreated cells. In terms of viability, the treated cells behaved exactly as the untreated ones for both UV and MNNG. The observed behaviour of the treated cells was found to be stable for during the 50 passages studied.

Animals↗
PubMedDate not supplied

Surgical resection of gastric cancer in the octogenarian population.

The medical records of 80 patients whose mean age was 81.1 years (range 80 to 94 years) were retrospectively evaluated for morbidity, mortality, and survival following gastric resection for gastric carcinoma. The overall 5-year survival of 68 patients who had undergone a total or subtotal gastrectomy for adenocarcinoma was 11%, with a mean and median survival of 25 and 175 months, respectively. In contrast, eight patients who did not undergo gastric resection for adenocarcinoma were found to have a mean and median survival of only 3.6 and 2.0 months, respectively. The 30-day perioperative morbidity and mortality rates for patients who had undergone gastric resection were 45.8% and 5.0%, respectively. The total gastric resection group had no perioperative deaths or anastomotic leaks. We conclude that with careful selection of patients and precise surgical technique, gastric resections can safely be performed in octogenarian patients with minimal morbidity and mortality.

Adenocarcinoma↗
PubMedDate not supplied

Peripheral eosinophilia in the diagnosis of chronic rhinosinusitis.

PURPOSE: To determine the relationship between peripheral blood eosinophilia and chronic rhinosinusitis. MATERIALS AND METHODS: A retrospective review was conducted of consecutive operative cases during 1 calendar year. The preoperative complete blood count (CBC) were tabulated for three groups of patients: those undergoing endoscopic sinus surgery, those undergoing septoplasty with turbinate reduction alone, and a nonrhinologic control group. Statistical analysis was performed to determine differences in the components of the CBC among these three groups of patients and to identify significant associations between abnormal peripheral eosinophil counts and these diagnoses. RESULTS: A total of 87, 32, and 92 patients were identified for the endoscopic sinus surgery (ESS), septoplasty, and control groups, respectively. Significant differences in the percentages of eosinophils, lymphocytes, and neutrophils were noted among the three groups (P <.05). Comparison among groups indicated that ESS patients had significantly higher percent peripheral eosinophilia when compared with both the control group and septoplasty group (P <.001 and P =.010, respectively); no significant difference was noted between the septoplasty group and the control group (P =.627). The sensitivity and specificity of the peripheral eosinophil count for chronic sinusitis were 49.4% and 84.7%, respectively. CONCLUSIONS: The peripheral eosinophil count in chronic sinusitis is elevated compared with both a nonrhinologic control group and a group of patients with septal deviation. Furthermore, abnormally elevated eosinophil counts are associated with chronic sinusitis but not chronic rhinitis alone. However, this association is not strong enough to be used in the diagnosis of chronic sinusitis because of poor sensitivity.

Adult↗
PubMedDate not supplied

Chronic rhinosinusitis: is the nose really involved?

To determine whether chronic rhinitis usually accompanies chronic sinusitis, and critically examine the concept of chronic rhinosinusitis, paired specimens of nasal septal mucosa and ethmoid sinus mucosa were obtained in a prospective cohort of 42 patients undergoing endoscopic sinus surgery for chronic rhinosinusitis. The histopathological degree of inflammation for each specimen was scored using a five-point rating scale. Cell counts for eosinophils and inflammatory cells per high-power field (HPF) were determined. Mean patient age was 40.5 years and mean Lund score was 9.3. The inflammation grade of the septal mucosa was within one point of the ethmoid mucosa in 36 (85.7%) cases, and correlated exactly in 24 patients (57.1%). A statistically significant correlation was found between septal and ethmoid mucosa inflammation grades (p = 0.048). No significant difference in mean non-eosinophilic inflammatory cell count per HPF was noted betmeen ethmoid mucosa and septal mucosa (48.2 versus 54.3 cells/HPF, p = 0.061, power = 0.873). Ethmoid mucosa had a significantly higher mean eosinophil count than septal mucosa (6.6 versus 1.9 cells/HPF, p < 0.001). For combined inflammatoty cell counts, no significant difference in cell counts was noted (54. 7 cells/HPF ethmoid versus 56.1 septal, p = 0.670, power = 0.847). Histopathologic evidence of rhinitis is associated with chronic sinusitis. This supports the concept of rhinosinusitis rather than sinusitis alone. Eosinophils are found in significantly higher numbers in sinus mucosa than in nasal mucosa, suggesting a site-specific role in rhinosinusitis.

Adult↗