Search PubMed⌕ Search

Biomedical subjects

A Chakrabarty

Publications and source records attributed to A Chakrabarty.

48 records · Page 3Linked to original sources
PubMed1988

Primary choice of intervention for distal ureteric stone: ureteroscopy or ESWL?

Either transurethral ureteroscopy (URS) or extracorporeal shock wave lithotripsy (ESWL) was the primary method of intervention in two series of patients presenting consecutively with stones located in the ureter distal to the radiological marking of the sacroiliac joint. Of 65 patients treated by URS, successful evacuation of the major part of the stone was achieved in 97% in one or two sessions. Of those subsequently attending for review, 93% proved stone-free but 3% required surgery for serious complications. In the ESWL series of 53 patients, successful stone fragmentation was recorded in 94%, with 2 patients requiring a supplementary endourological or surgical procedure. No significant complications were related to ESWL and 90% of those followed up after successful ESWL proved stone-free at 6 weeks. In uncomplicated cases, the mean procedure time for ESWL was one-third of that required for URS and the hospital stay one-half. It is suggested that ESWL should be the primary method of intervention in patients with distal ureteric stone, with URS reserved for the small number that prove refractory to such treatment.

Endoscopy↗
PubMed1976

Isolation of plasmid deoxyribonucleic acid from Pseudomonas putida.

Conditions suitable for reproducible recovery of covalently closed circular deoxyribonucleic acid from strains of Pseudomonas putida containing degradative plasmids (CAM, SAL, OCT, etc.) have been defined. These degradative plasmids could not be isolated by the usual procedure, whereas RP1, an R factor of the P group, present in the isogenic strain of P. putida, was isolated equally well by either the usual procedure or the modified procedure. Characterization by electron microscopy of RP1 deoxyribonucleic acid confirmed the molecular weight (about 40 X 10(6)) previously determined by sucrose gradient centrifugation.

Biodegradation, Environmental↗
PubMedDate not supplied

Influence of tumor site on the therapy of murine kidney cancer.

OBJECTIVE: The purpose of this study was to evaluate the influence of tumor site on the therapy of an experimental murine kidney cancer model, Renca. METHODS: Equal number of tumor cells were injected subcutaneously, intraperitoneally, sub-renal capsule, and intravenously to induce tumors. The animals were then assessed for growth of the primary tumor, metastases and survival. Immunohistochemistry and flow cytometry was performed to identify the phenotype of infiltrating lymphocytes. Tumor bearing animals were treated with high dose interleukin-2 or whole body radiation, and response of the primary tumors as well as the metastases was assessed. RESULTS: Renca tumors grew well regardless of the methods of induction. Spontaneous metastasis could be best induced in the sub-renal capsule model. More consistent numbers of pulmonary metastases were obtained by intravenous injection of the tumor cells. Immunotherapy was able to reduce the size of the primary tumor as well as the number of metastasis. Whole body radiation caused some reduction in the primary tumor but did not have a major effect in reducing metastasis. CONCLUSIONS: The Renca model is a suitable animal model to study the response to different therapeutic interventions. The site of the tumor growth is not a significant variable in the response to treatment.

Adenocarcinoma↗
PubMedDate not supplied

Radiation therapy enhances the therapeutic effect of immunotherapy on pulmonary metastases in a murine renal adenocarcinoma model.

In order to improve the efficacy of immunotherapy, we have evaluated the effects of radiation therapy combined with interleukin 2 (IL-2) treatment in a murine metastatic renal adenocarcinoma model (Renca). Pulmonary metastases were induced in Balb/c mice by intravenous injection of Renca and five days later a sublethal dose of radiation (300 rads) was administered either to the whole body or to the left lung only. One day following radiation, immunotherapy was given for 5 consecutive days of IL-2 at 5,000 Cetus units intraperitoneally, twice daily. The animals were either sacrificed on day 23 or 33 to assess tumor burden, or were followed for long term survival. We found that pretreatment with irradiation greatly enhanced the therapeutic efficacy of immunotherapy and was manifested by a significant reduction in pulmonary metastases and an increase in survival. When combined with immunotherapy, local tumor irradiation was not only as effective as whole body irradiation, but irradiation of one lung reduced the number of metastases similarly in both lungs. This suggests that local tumor irradiation may act through a systemic mechanism to increase the anti-tumor response mediated by IL-2 therapy.

Animals↗