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Biomedical subjects

J R Warren

Publications and source records attributed to J R Warren.

82 records · Page 5Linked to original sources

Carbamylcholine stimulation of protein secretion in pancreatic acinar carcinoma of rat.

Pancreatic acinar carcinoma fragments, pulse-chase labeled with [3H]-leucine, responded to carbamylcholine chloride by increased secretion of [3H]leucine-labeled protein into external buffer medium. Secretion of labeled protein by the carcinoma fragments increased in concentration-dependent fashion between 10(-8) -10(-5) M carbamylcholine, was completely inhibited at 4 degrees C, and was accompanied by an equivalent increase in the secretion of preformed amylase. A maximally effective carbamylcholine concentration of 10(-5) M was observed for both carcinoma fragments and normal pancreas lobules. However, the maximal rate of protein secretion by the carcinoma fragments was only approximately one-fifth the rate determined for the normal pancreas lobules. This modest secretory response indicates a population of partially differentiated cells in the pancreatic acinar carcinoma which secrete less enzyme than fully differentiated adult pancreatic acinar cells. Secretory responsiveness can be utilized as a quantitative acinar cell response in studies on differentiation in pancreatic carcinoma.

Amylases↗

Prospective double-blind trial of duodenal ulcer relapse after eradication of Campylobacter pylori.

100 consecutive patients with both duodenal ulcer and Campylobacter pylori infection were followed up to see whether eradication of C pylori affected ulcer healing or relapse. Patients were randomly assigned to 8 weeks of treatment with cimetidine or colloidal bismuth subcitrate (CBS), with tinidazole or placebo being given concurrently from days 1 to 10, inclusive. Endoscopy, biopsy, and culture were done at entry, in weeks 10, 22, 34, and 62, and whenever symptoms recurred. There was no maintenance therapy. C pylori persisted in all of the cimetidine-treated patients and in 95% of those treated with cimetidine/tinidazole, but was eradicated in 27% of the CBS/placebo group and 70% of the CBS/tinidazole group. When C pylori persisted, 61% of duodenal ulcers healed and 84% relapsed. When C pylori was cleared 92% of ulcers healed (p less than 0.001) and only 21% relapsed during the 12 month follow-up period (p less than 0.0001).

Adult↗

Webifying a patient interview support application.

This paper reports on the software engineering challenges, and resultant benefits experienced, in porting an interactive, knowledge-based system from Microsoft Windows to the World Wide Web for evaluation purposes. The Patients Interview Support Application (PISA) is a program intended for operation by a non-expert clerk to interview an ambulatory primary care patient. The PISA code had to be re-written substantially to address the 'connectionless' nature of Web dialog and to work in terms of dynamically generated HTML forms; however, it was possible to avoid any revision of the central knowledge-base or inference engine. The resultant Web environment attracted thought-provoking and detailed feedback from users, indicating that significant attention can be obtained from the global community by mounting an interactive system on the Web. Specific enhancements to the PISA's artificial intelligence are suggested by user reaction. A future global health informatics 'marketplace' with a multidue of Web-based system components available for composition of health information systems is envisioned.

Artificial Intelligence↗

Cell differentiation in pancreatic cancer.

Cell differentiation in cancer of the exocrine pancreas is currently under intensive study. In this report, new developments are critically reviewed on the use of transplantable pancreatic carcinoma and the hybridoma technique to define cell membrane changes during pancreatic cancer growth. It is concluded that two categories of plasmalemma structure hold promise as differentiation markers specific for pancreatic cancer: (1) membrane receptors for cholinergic and peptide secretagogues and (2) membrane glycoproteins as detected by monoclonal antibodies. Assay of secretagogue receptors and membrane glycoprotein antigens will be central to elucidation of mechanisms of pancreatic carcinoma cell differentiation (? stem cell differentiation or retrodifferentiation) and, hopefully, will provide tumor-specific or tissue-specific markers for the laboratory diagnosis and monitoring of pancreatic cancer.

Animals↗