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Biomedical subjects

T Woodward

Publications and source records attributed to T Woodward.

8 recordsLinked to original sources
PubMed1997

Apoptosis is inhibited early in the dysplasia-carcinoma sequence of Barrett esophagus.

OBJECTIVE: To evaluate the alteration of apoptosis in the esophageal epithelium during the esophagitis-Barrett esophagus-adenocarcinoma sequence. DESIGN: Archival tissue samples of 85 lesions in 58 cases were used. The lesions represented 7 groups: normal esophagus (n = 10), reflux esophagitis (n = 12), Barrett metaplasia (n = 21), Barrett low-grade dysplasia (n = 17), Barrett high-grade dysplasia (n = 5), well- or moderately differentiated adenocarcinoma (n = 10), and poorly differentiated adenocarcinoma (n = 10). Apoptotic cells with fragmented DNA were detected by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate (dUTP)-biotin nick end labeling (TUNEL) method. Monoclonal antibodies against bcl-2 protein were applied using the avidin-biotin complex immunoperoxidase method. RESULTS: The esophagitis group showed many apoptotic cells on the epithelial surface; in the other groups, few apoptotic cells were seen. Weak bcl-2 expression was seen in the basal cells in normal subjects and those with esophagitis. There was overexpression of bcl-2 in 72% of Barrett metaplasia, 100% of Barrett low-grade dysplasia, 25% of Barrett high-grade dysplasia, 40% of well- or moderately differentiated adenocarcinoma, and 20% of poorly differentiated adenocarcinoma. CONCLUSIONS: Increased apoptosis in reflux esophagitis may be a protective mechanism counteracting increased proliferation. Inhibition of apoptosis by overexpression of bcl-2 protein occurs early in the dysplasia-carcinoma sequence of Barrett esophagus. The resulting prolongation of cell survival may promote neoplastic progression. Despite the absence of apoptosis, bcl-2 was not widely overexpressed in Barrett high-grade dysplasia and adenocarcinoma, suggesting that cells acquire other ways of avoiding apoptosis as malignancy appears.

Adenocarcinoma↗
PubMed1996

Evolution of insulin-like growth factor-1, prostaglandin E2, and mitogenic activity of bovine mammary primary lymph during the dry period and lactogenesis.

Four pregnant cows near the end of lactation were fitted with a catheter in a lymph duct afferent to the supramammary lymph node. Cows were dried off 3 d after surgery, and samples of lymph were collected daily from the day of surgery until 4 d postpartum. Samples of blood and mammary secretions were taken before and after drying off and at parturition. Concentrations of most metabolites were lower in lymph than in serum. Concentrations of IGF-I and prostaglandin E2 were not affected at drying off but decreased and increased, respectively, at parturition. All IGF-binding proteins that were present in serum were also present in lymph fluid, but the binding activity was lower. Mitogenic activities of lymph samples taken at various physiological stages were determined on mammary epithelial (MAC-T) and fibroblast cell lines. Lymph was mitogenic, but mitogenic activity was not related to physiological stages. The correlation was high between mitogenic activity of lymph on MAC-T cells and the content of prostaglandin E2 in lymph. Supplementation of lymph with additional prostaglandin E2 increased mitogenic activity, and neutralization of lymph by antibodies reduced mitogenic activity. Basal medium conditioned by the epithelial cell line contained 100 to 250 pg/ml of immunoassayable prostaglandin E2.

Animals↗
PubMed1992

Adopting an information management approach to the design and implementation of information systems.

As the NHS adopts an information management approach to coordinated handling of total information resources, methods of systems analysis and design require assessment to ensure that they are appropriate. Mandatory use of Structured Systems Analysis and Design Methodology (SSADM) may be encouraging a damagingly narrow view of information systems. Research is described in which an holistic view of information systems is applied, allowing the needs of information users to play a stronger role in determining how information will be supplied to them. The techniques may also assist the training activities associated with implementing new systems.

Health Promotion↗
PubMed1990

Rh immunization by the partial D antigen of category DVa.

Reported here is the first example of a partial D antigen stimulating the production of anti-D: stimulation was of fetal origin. During her second pregnancy, anti-D developed in the serum of a D-negative mother who had received Rh immunoglobulin after the birth of her first D-positive child. Her second baby had moderate neonatal jaundice and was successfully treated by phototherapy. Subsequently the red cells of the father and of the first child were shown to carry a partial D antigen of category DVa type. Six available batches of Rh immunoglobulin reacted with DVa cells.

Adult↗