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Biomedical subjects

G C Budd

Publications and source records attributed to G C Budd.

31 records · Page 2Linked to original sources
PubMed1976

Structure and function of cardiac mitochondria in exhausted guinea pigs.

The ultrastructure and functional capacity of mitochondria from hearts of exhausted guinea pigs were compared to those from rested animals. Electron micrographs of heart ventricles were examined for ultrastructural alterations, and functional capacity was studied by oxygen polarography. General swelling of mitochondria from exhausted animals was indicated by a 41% reduction in mitochondrial surface/volume ratio and a 22% increase in volume density of mitochondria from exercised animals when compared to those from controls. The yield of isolated mitochondria from exhausted guinea pigs was similar to that for control animals. In the presence of all substrates tested the rate of oxygen consumption was lower in the exhausted animals than in the controls. The ADP/O ratios and respiratory control indices for pyruvate, succinate and ascorbate were not systematically affected by exercise. With glutamate as substrate respiratory control was reduced in exercised guinea pigs. These experiments suggest that the structure of myocardial mitochondria from exhausted animals is sufficient to maintain normal ADP/O ratios but is not adequate to maintain normal rates of respiration.

Animals↗
PubMedDate not supplied

Insulin or insulin-like peptides in the human pituitary.

Human pituitary cells and pancreatic islet beta cells from surgical and autopsy material showed positive immunoreactivity to anti-porcine insulin antisera demonstrating the presence in these tissues of insulin or insulin-like immunoreactive material. Glutaraldehyde-fixed, one micron epoxy sections were used and the polymerized resin was removed prior to staining with the peroxidase anti-peroxidase technique using guinea pig antisera to porcine insulin. Pancreatic beta cells served as the positive control, and appropriate negative controls were also utilized.

Histocytochemistry↗
PubMedDate not supplied

Detection of oncogene mRNA sequences in cultured cells by in situ hybridization.

The present study was undertaken to determine the feasibility of using in situ hybridization techniques to identify oncogene transcription in cultured cells. Following in situ hybridization with 32P-labeled v-src and v-Ha-ras DNA probes, src and Ha-ras related transcripts were identified in cell lines transfected with v-src and Ha-ras, respectively. In both the v-src and c-Ha-ras transfected cell lines, the number of silver grains over individual cells were significantly higher (p less than 0.001, t-test) than in a non-transfected, non-tumorigenic, rat esophageal epithelial cell line. There was a highly variable number of silver grains above individual cells. Significantly fewer silver grains were counted over cells that had been preincubated with either non-labeled v-src or v-Ha-ras DNA or that were pretreated with RNase A. Both oncogene transfected cell lines contained approximately 10 times more oncogene related mRNAs than non-transfected cells as judged by the numbers of silver grains over individual cells. Filter-hybridization analysis of the transfected and non-transfected cell lines confirmed that the expression of src and Ha-ras transcripts was higher in the transfected cell lines than in the non-transfected cell line. Therefore, the in situ hybridization technique would appear useful for the identification of oncogene transcripts in single cells and could potentially be applied to cytological preparations of human cells and to human tumor cells in culture.

Animals↗
PubMedDate not supplied

Preproinsulin messenger ribonucleic acid in the rat adrenal gland.

Many studies support the concept of insulin synthesis in tissues other than the pancreas. Our previous investigations have demonstrated the presence of insulin immunoreactivity in the adrenal medulla of the rat. This immunoreactivity was found to be associated with the chromaffin granule. This study is directed at isolating the messenger ribonucleic acid that encodes for preproinsulin. Reverse transcription coupled with polymerase chain reaction was used. Complementary deoxyribonucleic acid (cDNA) was amplified, extracted and reamplified. It was then subjected to digestion with four different restriction endonuclease enzymes. Its resemblance to the corresponding cDNA that encodes for preproinsulin I in the rat was established. Our results suggest that insulin is synthesized in the rat adrenal gland for autocrine, paracrine, neuromodulation or local physiologic function.

Adrenal Glands↗