Biomedical subjects

R J Bryant

Publications and source records attributed to R J Bryant.

11 recordsLinked to original sources

PubMed2006

Ki67 staining pattern as a diagnostic tool in the evaluation of lymphoproliferative disorders.

AIMS: To evaluate a group of lymphoid proliferations using only Ki67-stained slides to determine the value of the pattern of proliferating cells in diagnosis. Ki67 immunohistochemistry allows evaluation of the distribution of proliferating cells in addition to simply determining the proliferation rate of cells. METHODS AND RESULTS: Three observers, using a Ki67-stained slide only, studied 149 cases from five diagnostic groupings: follicular hyperplasia, mixed pattern hyperplasia, localized Castleman's disease, follicular lymphoma and marginal zone lymphoma. The sensitivity for benign lesions varied from 94% to 97% among the three observers. Follicular lymphomas were recognized as neoplastic with a sensitivity of 96% and 100% by two of the observers. Marginal zone lymphoma was recognized as neoplastic in 67-73% of cases. CONCLUSIONS: The Ki67 stain alone is a powerful tool for distinguishing benign from malignant proliferations within the selected groups. Nuances and pitfalls in the interpretation of Ki67 staining pattern are discussed.

Castleman Disease↗

PubMed2003

Alpha and beta-galactosidase activities and oligosaccharide content in peanuts.

Thirty-three peanut cultivars were examined for their alpha-1,6 and beta-1,4 galactosidase activities and oligosaccharide contents along with proximate compositions. The average moisture, protein, fat, ash, and carbohydrate contents were: 4.9%, 26.6%, 43.1%, 2.3% and 23.1%, respectively. The corresponding coefficients of variation were: 5.2%, 10.1%, 7.2%, 7.8% and 15.7%, respectively. Raffinose and stachyose contents (%) ranged from 0.05 to 0.12 and 0.31 to 0.61, respectively. The specific activity (micromol product/min/mg protein) of crude preparation of alpha-galactosidase for the 33 cultivars ranged from 1.096 to 2.784 for the non-germinated seeds and from not being detected in some samples up to 2.432 for the germinated seeds; the mean values for non-germinated and germinated seeds were: 1.781 and 1.410, respectively. The specific activity of beta-galactosidase ranged from 0.101 to 1.727 in the non-germinated seeds and from not being detected in some samples up to 0.898 in the germinated seeds. Germination decreased the activity of both galactosidases significantly (p < or = 0.05).

Arachis↗

PubMed2003

Racial differences in bone turnover and calcium metabolism in adolescent females.

Blacks develop a higher peak bone mass than whites which is associated with a reduced risk for bone fracture. The physiological basis for the difference in bone mass was investigated by metabolic balance and calcium kinetic studies in adolescent black and white girls. The hypothesis that the greater peak bone mass in blacks compared with whites is due to suppressed bone resorption was tested. Subjects were housed in a supervised environment for 3 wk during which time they consumed a controlled diet and collected all excreta. Subjects were given stable calcium isotopes orally and intravenously after 1 wk adaptation. Blacks have greater calcium retention (mean +/- SD, 11.5 +/- 6.1 vs. 7.3 +/- 4.1 mmol/d, P < 0.05) consistent with greater bone formation rates (49.4 +/- 13.5 vs. 36.5 +/- 13.6 mmol/d, P < 0.05) relative to bone resorption rates (37.4 +/- 13.2 vs. 29.4 +/- 10.9 mmol/d, P = 0.07), increased calcium absorption efficiency (54 +/- 19 vs. 38 +/- 18%, P < 0.05) and decreased urinary calcium (1.15 +/- 0.95 vs. 2.50 +/- 1.35 mmol/d, P < 0.001), compared with whites. The racial differences in calcium retention in adolescence can account for the racial differences in bone mass of adults.

Adolescent↗

PubMed1999

The new dietary reference intakes for calcium: implications for osteoporosis.

The new Dietary Reference Intakes (DRI) for calcium were released August 13, 1997 by the Food and Nutrition Board of the National Academy of Science. Unlike the RDA's which established the minimal amounts of nutrients needed to be protective against possible deficiency, the new values are designed to reflect the latest understanding about nutrient requirements directed at optimizing health in individuals and groups. Adequate calcium intake recommendations were set at levels associated with desirable retention of body calcium since high bone density is known to be less susceptible to fractures. Recommended intake for adults is 1000 to 1200 mg/day. The majority of people do not consume these levels of calcium. The upper tolerable limit for calcium was set at 2.5 g/day.

Aging↗

PubMed1996

Ownership and uses of human tissue: does the Nuffield bioethics report accord with opinion of surgical inpatients?

OBJECTIVE: To compare opinion of surgical inpatients with the conclusions of the report of the Nuffield Council on Bioethics regarding the ownership and uses of human tissue. DESIGN: Survey of results of questionnaires completed by patients. SETTING: Large teaching hospital. SUBJECTS: 384 postoperative adult surgical patients. RESULTS: There was strong support among patients for the use of tissues in medical education, research, and science with the exception of those tissues which may transmit disease to others. Few patients (39; 10%) believed that they retained ownership of tissue removed at surgery. Most believed that the tissue belonged to the hospital (103; 27%), to nobody (103; 27%), or to the laboratory (77; 20%). Most patients had not been given any information about the possible uses of their tissues after removal. CONCLUSIONS: Surgical inpatients seem to endorse the conclusions of the Nuffield report regarding the ownership and uses of human tissue. The recommendations regarding patient information and consent procedures should be implemented at the earliest opportunity.

Adult↗

PubMed1982

Interactions of bacterial and amoebal populations in soil microcosms with fluctuating moisture content.

Sterilized soil samples (20 g of soil per 50-ml flask), amended with 600 mug of glucose-carbon and 60 mug of NH(4)-N . g of dry soil, were inoculated with bacteria (Pseudomonas paucimobilis) alone or with bacteria and amoebae (Acanthamoeba polyphaga). We used wet-dry treatments, which involved air drying the samples to a moisture content of approximately 2% and remoistening the samples three times during the 83-day experiment. Control treatments were kept moist. In the absence of amoebae, bacterial populations were reduced by the first drying to about 60% of the moist control populations, but the third drying had no such effect. With amoebae present, bacterial numbers were not significantly affected by the dryings. Amoebal grazing reduced bacterial populations to 20 to 25% of the ungrazed bacterial populations in both moisture treatments. Encystment was an efficient survival mechanism for amoebae subjected to wet-dry cycles. The amoebal population was entirely encysted in dry soil, but the total number of amoebae was not affected by the three dryings. Growth efficiencies for amoebae feeding on bacteria were 0.33 and 0.39 for wet-dry and constantly moist treatments, respectively, results that compared well with those previously reported for Acanthamoeba spp.

Journal Article↗

PubMed1979