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Biomedical subjects

F E Johnson

Publications and source records attributed to F E Johnson.

At least 145 records · Page 8Linked to original sources
PubMed1985

Carcinoembryonic antigen in experimental rat gastrointestinal carcinoma.

Detection of gastric carcinoma in the experimental rat can be difficult. We investigated whether or not serological testing for carcinoembryonic antigen might aid in the diagnostic process. Twenty-five young adult male Wistar rats were studied; 15 were treated with the carcinogen N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), and 10 received no treatment. A complete autopsy was done on the 22 animals (12 in MNNG group, 10 in control group) that completed the 37-week study. Serum obtained at autopsy was evaluated by radioimmunoassay for the presence of CEA-like immunoreactivity. Grossly normal stomach, as well as gastric and small bowel cancers, were also stained for CEA. Of the 12 autopsied animals in the MNNG group, eight had a total of 12 cancers (seven gastric and five proximal small bowel); in no animal was an elevated serum CEA level detected. Immunoreactive tissue CEA was demonstrable in normal stomach and in gastrointestinal cancers; the tumors usually stained less intensely than adjacent normal stomach and did not exhibit normal intracellular CEA distribution.

Animals↗
PubMed1984

Small cell undifferentiated carcinoma of the esophagus. Case report with hormonal studies.

This report details clinical and pathologic aspects of a case of small cell undifferentiated carcinoma of the esophagus. Transmission electron microscopic examination demonstrated neurosecretory granules, and indirect immunoperoxidase stain for adrenocorticotropic hormone (ACTH) was positive. However, the authors detected no abnormal hormone levels in urine or blood. The calculated tumor doubling time was approximately 2 days. The fulminant nature of this carcinoma was also evident from the rapid clinical progression in spite of surgical excision, radiotherapy, and chemotherapy.

Adrenocorticotropic Hormone↗
PubMed1984

Effect of cyclosporine on carcinogenesis induced in rats by N-methyl-N'-nitro-N-nitrosoguanidine.

Cyclosporine administration has been associated with the development of lymphomas in human transplant patients as well as animals. Its effect on the genesis of common epithelial carcinomas is unknown. To investigate this N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) was administered in drinking water to Wistar rats. Seventy-five young healthy male animals were divided into six groups and received cyclosporine alone, cyclosporine followed by MNNG, MNNG alone, cyclosporine during MNNG administration, MNNG followed by cyclosporine, and no treatment. Cyclosporine seemed to have minimal overall health effects and no cancers were encountered in the group receiving this agent alone. Animals in all carcinogen-treated groups developed gastric and upper intestinal carcinomas by Week 39. No statistically significant differences among carcinogen-treated groups were evident with respect to tumor incidence, histology, or distribution. There appeared to be trends (not statistically significant) toward a greater incidence of small bowel carcinomas in animals receiving cyclosporine plus MNNG as compared to those receiving MNNG alone; greater multiplicity of small intestinal carcinomas in animals receiving cyclosporine after MNNG as compared to all other groups; and greater incidence of small bowel tumors greater than 1 cm3 in animals receiving cyclosporine after MNNG as compared to all other groups. The median total tumor volume in the animals receiving cyclosporine following carcinogen was significantly greater than in any other group. This study does not support a policy of aggressive surveillance for gastrointestinal carcinoma in the human population receiving cyclosporine.

Animals↗
PubMed1983

Neoplastic changes in transposed deltopectoral skin.

In a patient who had undergone pharyngeal resection and reconstruction with transposed deltopectoral skin, multiple benign verrucous tumors developed in the neopharynx. These did not resemble the carcinoma for which the original ablative surgery was performed but required extensive resection for restoration of adequate swallowing. Although this complication appears to be rare, the number of patients at risk is sizable, and further examples may be expected in the future.

Cell Transformation, Neoplastic↗
PubMed1983

Cholecystokinin inhibits pancreatic and hepatic carcinogenesis.

Cholecystokinin (CCK) has trophic actions on abdominal viscera. To determine whether CCK enhances malignant growth in a similar fashion, we gave hamsters CCK together with di-isopropanol nitrosamine (DIPN), a known pancreatic and hepatic carcinogen. After 40 weeks of injections, those animals receiving both DIPN and CCK developed no cancers, while the control animals receiving DIPN alone developed pancreatic and hepatic carcinomas. This suggests that CCK inhibits carcinogenesis in this model. Although the mechanism of this effect is unknown, some implications for human carcinogenesis are testable by currently available methods.

Animals↗