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Biomedical subjects

J B Adams

Publications and source records attributed to J B Adams.

At least 91 records · Page 5Linked to original sources
PubMed1977

Steroid hormones and human breast cancer. An hypothesis.

The likely occurrence of two distinct types of human breast cancer is discussed. In the development of the "Western-environmental" or "adrenal" type, it is proposed that dehydroepiandrosterone sulphate (DHEAS), secreted by the adrenal, may be implicated. This steroid is metabolized by mammary tumors to active androgens and estrogens. That these metabolic pathways are very similar to that in skin is emphasized and this is possibly explained by evolution of the mammary gland from primitive sweat glands. Formation of DHEAS from DHEA in mammary tumors, claimed to be correlated with an individual subject's prognosis and response to hormone ablation, is discussed in the light of a possible regulatory role of the sulphotransferase. It is proposed furthermore that a specific control of DHEAS secretion in the adrenal may exist at the level of the sulphurylation step. Nutritional factors are also possibly implicated here and these are discussed in the light of: 1) a possible higher secretion rate of DHEAS in obese subjects; and 2) the low breast cancer incidence in the Japanese and the accompanying low blood DHEAS levels.

17-Ketosteroids↗
PubMed1977

Dehydroepiandrosterone sulfotransferase as a possible shunt for the control of steroid metabolism in human mammary carcinoma.

Human primary mammary tumors were examined to determine what factors were of importance in deciding relative rates of sulfurylation of dehydroepiandrosterone and 17beta-estradiol, such rates having been shown to correlate with the patient's prognosis and response to adrenalectomy (T. L. Dao and P.R. Libby. Enzymic Synthesis of Steroid Sulfate by Mammary Cancer and Its Clinical Implications. Natl. Cancer Inst. Monographs, 34: 205-210, 1971). The sulfurylation of dehydroepiandrosterone and 17beta-estradiol was studied in 41 tumors in vitro using tumor cytosol, adenosine triphosphate, [35S]SO42-, Mg2+, and added steroid. Six tumors showed no sulfurylating ability, 9 sulfurylated dehydroepiandrosterone at a rate greater than that for 17beta-estradiol (ratio, greater than 1), and 26 sulfurylated dehydroepiandrosterone at a rate lower than that for 17beta-estradiol (ratio, less than 1). Evidence was obtained that low levels of dehydroepiandrosterone sulfotransferase were responsible for ratios of less than 1, in many instances. Adenosine 3'-phosphate 5'-phosphosulfate synthesis and steroid sulfotransferase activities were measured in 30 tumors. A significant correlation was found between synthesis of the former and levels of estrogen sulfotransferase, but this relationship did not hold for dehydroepiandrosterone sulfotransferase, again due to low levels of this enzyme in many tumors. It is suggested that dehydroepiandrosterone sulfate formation in the tumors is mainly controlled by the sulfotransferase, which acts as a shunt in regulating the level of free dehydroepiandrosterone, and related compounds, available for metabolism to steroids influencing the growth of mammary epithelial cells.

Adrenalectomy↗
PubMed1977

A computerized prenatal record.

An entirely computerized ambulatory medical record system is operational in a large health maintenance organization. A unique subsystem was designed for use in prenatal care, in which the provider's completion of a single encounter form at the time of visit meets all the information requirements of care delivery, administration, and quality assurance. Instead of using a conventional paper chart, computer-generated summaries and flow charts are automatically provided for scheduled visits and for use as a hospital preadmission record, significantly reducing the provider effort expended on record keeping. On-line inquiry function is also available using terminals at the ambulatory center and the hospital. The computer data base has been used for quality assurance studies in prenatal care. The system is well accepted by providers, is reliable, and is cost effective.

Computers↗
PubMed1976

Steroid metabolism by human mammary carcinoma.

The ability of human mammary tumors to convert 7alpha 3H-testerone to estrogens was examined in order to determine whether this bore any relationship to estrogen receptor and steroid sulfurylation levels; such levels being indicative of hormone dependency. In 8 out of 9 tumors, formation of estradiol-17beta from testosterone was demonstrated. Those tumors showing the lowest conversion of testosterone to estradiol-17beta possessed the highest levels of dehydroepiandrosterone sulfotransferase which lends support to data implicating sulfurylation in the regulation of steroid metabolism in human tumors. All tumors activated sulfate to adenosine-3'-phospho-5'-phosphosulfate and the concentrations were significantly correlated withe the recorded levels of dehydroepiandrosterone sulfate. Estrogen receptor levels did not show any obvious relationship to the other parameters.

Breast Neoplasms↗
PubMed1969

Teichoic acids possessing phosphate-sugar linkages in strains of Lactobacillus plantarum.

Cell walls of strains of Lactobacillus plantarum lacking the group D precipitinogen (a glucosylribitol teichoic acid) contain glucosylglycerol teichoic acid in which the glycosidic substituents are attached to the primary hydroxyl group of glycerol. Three distinct repeating units have been isolated from the teichoic acid preparation of strain C106, indicating either that the polymer is complex or that the wall contains a mixture of teichoic acids. Walls of streptobacteria differ from those of L. plantarum and contain neither teichoic acid nor diaminopimelic acid.

Antigens↗