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Biomedical subjects

S Das

Publications and source records attributed to S Das.

At least 721 records · Page 40Linked to original sources
PubMed1977

Enzymatic responses of transplanted tumour cells towards estrogen, progesterone and testosterone.

The influence of estrogen, progesterone and testosterone on the activities of alkaline and acid phosphatases, adenosine triphosphatase and succinate dehydrogenase were determined by cytochemical methods in sarcoma 180 and Ehrlich's carcinoma cells transplanted in male and female Swiss mice. The results revealed differential effects of the sex hormones on different enzymes which seemed to depend on the type of tumour cell studied and the sex of the host mice.

Acid Phosphatase↗
PubMed1976

Multiple primary adenocarcinomas of urogenital tract.

A case of multiple adenocarcinoma arising from the kidney, bladder, and prostate is presented with a relevant discussion of the possible factors of pathogenesis. A staged approach of radical extirpative surgery is suggested.

Adenocarcinoma↗
PubMed1976

A preliminary study in treatment of non-Hodgkin's lymphoma by whole-body irradiation.

Seven cases of generalised non-Hodgkin's lymphomas (lymphosarcoma, giant follicular lymphoma and reticulum cell sarcoma) were treated by whole-body irradiation as a preliminary study in this centre. Historical background, rationale, treatment technique, and results of such treatment are discussed in this paper. All patients responded, two completely, and five partially. A multicentre clinical trial is recommended to evaluate the results of whole-body irradiation in comparison with chemotherapy in generalised non-Hodgkin's lymphomas.

Aged↗
PubMed1976

Terminal nitrogen rise.

Eighteen-breath nitrogen washouts were performed on eight subjects. Each washout could be simulated by a four-compartment model, each compartment with a different ventilation-to-volume ratio and a variable contribution to expiratory flow. In large breaths initiated near residual volume, a terminal nitrogen rise (TNR) was seen. To account for the TNR with this model, there were relatively small changes in flow from compartments with markedly different nitrogen concentration. Reasons are given for believing these compartments could not be the upper and lower lung. Three of these subjects were studied in the supine, seated, and head-down positions. The TNR was seen at the same lung volume in all positions. At routine bronchospirometry in a second group of subjects, sampling with small catheters during a nitrogen washout showed a TNR in the expirate of lungs, lobes, segments, and subsegments in the upright and supine positions. Apparently a large vertical hydrostatic gradient is unnecessary to produce a TNR. Finally, the TNR was shown to occur at that lung volume where transpulmonary pressure is very small and changing rapidly with volume. This TNR was often followed by a terminal nitrogen fall while the lung was continuing to empty. The TNR occurs when flow from a large poorly ventilated compartment increases relative to the flow from other compartments. A model of lung in which the poorly ventilated compartment develops high specific compliance at low lung volume explains these data.

Adult↗
PubMed1976

The role of plasmin on the double antibody radioimmunoassay of carcinoembryonic antigen in human blood samples.

Double antibody radioimmunoassay (RIA) of carcinoembryonic antigen (CEA) on a series of freshly drawn out concurrent plasma and serum samples of normal human blood donors showed that the serum CEA values were invariably higher than the corresponding plasma CEA values. Extraneous addition of fibrinogen brought down the serum-CEA level to a value comparable to or less than the corresponding plasma value. The effect of certain factors associated with blood clotting, particularly Ca++, fibrinogen, and the fibrinolytic enzyme plasmin, was investigated. Ca++ was shown to play no role whereas the effect of fibrinogen was shown to be indirect in that it served as a specific substrate for plasmin, thereby preventing the plasmin degradation of the primary antibody used in the RIA. The finding stresses the role of enzymes like plasmin in double antibody RIA in general and may explain some of the anomalous results obtained when testing biologic material containing plasmin-like substances.

Binding Sites, Antibody↗
PubMed1976

Enzymatic responses of transplanted tumour cells towards estrogen, progesterone and testosterone.

The influence of estrogen, progesterone and testosterone on the activities of alkaline and acid phosphatases, adenosine triphosphatase and succinate dehydrogenase were determined by cytochemical methods in sarcoma 180 and Ehrlich's carcinoma cells transplanted in male and female Swiss mice. The results revealed differential effects of the sex hormones on different enzymes which seemed to depend on the type of tumour cell studied and the sex of the host mice.

Acid Phosphatase↗
PubMed1976

Modifications and evaluation of double antibody radioimmunoassay of human carcinoembryonic antigen.

Double antibody radioimmunoassay of carcinoembryonic antigen (CEA), a cancer-associated antigen of the human digestive system, was subjected to certain modifications and critically evaluated. Modifications pertained to: (a) the production of a high titer goat anti-CEA antiserum that was rendered highly specific by solid phase immunoabsorption with cyanogen bromide-activated Sepharose conjugates of normal plasma liver, and colon perchloric acid-soluble glycoprotein antigens: (b) the introduction of suitable alterations in the experimental conditions of radioiodination procedure to minimize and to prevent breakdown of the antigen, thus prolonging the storage of the labeled antigen; (c) the extended incubation period of CEA-anti-CEA immune reaction; and (d) the use of sodium acetate buffer, pH 6.1. Furthermore, the use of an automatic pipetting station for accurate and rapid reagent dispensation and statistical analysis of the radioimmunoassay data on a modern computer to ensure strict quality control of the assay provided some definite improvement over the existing assay.

Absorption↗
PubMed1975

Primary retroperitoneal seminoma. Report of a case and review of the literature.

A large retroperitoneal seminoma in a 42-year-old man is described, which appears to have arisen as a primary tumor at that site. The mechanism for the development of extragonadal germ cell tumors is discussed, and the criteria for their distinction from metastatic occult or regressed testicular neoplasms are re-emphasized. Awareness by clinicians of this entity may save individuals with this neoplasm from unnecessary orchiectomy.

Adult↗