Search PubMed⌕ Search

Biomedical subjects

R A Walker

Publications and source records attributed to R A Walker.

198 records · Page 11Linked to original sources
PubMed1981

Differentiation of human breast carcinomas: an immunohistological study of appropriate and inappropriate protein production.

Secretory piece of immunoglobulin A, a product of normal breast tissue, and beta 1 pregnancy-specific glycoprotein, a product of syncytiotrophoblast of placenta, have been demonstrated in breast carcinomas by an indirect immunoperoxidase method. A close relationship has been found between the site of staining within cells and tumour structure for both secretory piece, the appropriate protein, and beta 1 pregnancy-specific glycoprotein, the inappropriate protein. The reaction was at the periphery of cells in areas of tubular differentiation and was diffusely intracytoplasmic in solid groups of tumour cells. The poorly differentiated carcinomas have a low incidence of detection for both antigens but the tumours showing good histological differentiation appear to be functionally heterogeneous with some being negative for both proteins, some staining for the appropriate secretory piece of immunoglobulin A and the inappropriate beta 1 pregnancy-specific glycoprotein and only one out of 12 producing the appropriate protein alone.

Breast Neoplasms↗
PubMed1981

The cytochemical demonstration of oestrogen receptors in human breast carcinomas.

A cytochemical method has been used to demonstrate oestrogen receptor in histological sections of breast carcinomas, and has given similar qualitative results to the biochemical dextra-coated charcoal method. Two conjugation techniques were employed to couple horseradish peroxidase to 17 beta-oestradiol-6-O-carboxymethyloxime-bovine serum albumin. The periodate conjugation method led to a greater degree of coupling but a higher concentration was required for demonstration of oestrogen receptor than that needed when the two-stage glutaraldehyde conjugation method was use, even though this resulted in a lesser degree of coupling. Care in the preparation of tissue has been found to be essential. Formalin-fixed, paraffin-embedded tissue was unsuitable; rapid freezing of fresh tissue, only brief air-drying or acetone fixation of tissue sections and short-term storage were important. A correlation has been shown between the presence of oestrogen receptor in breast carcinomas and good histological differentiation. The poorer differentiated tumours were also found to contain fewer reactive cells.

Breast Neoplasms↗
PubMed1981

Vincristine, bleomycin, methotrexate, 5-fluorouracil, and prednisone in metastatic, hormonally unresponsive prostatic adenocarcinoma.

Patients with hormonally unresponsive prostatic adenocarcinoma were subjected to a five-drug chemotherapy program using bleomycin, 5-fluorouracil, methotrexate, vincristine, and prednisone. Analysis of survival curves indicated that deletion of an alkylating agent from this five-drug program reduced survival when patients with equal risk factors were compared. Bleomycin was poorly tolerated by this aged population.

Adenocarcinoma↗
PubMed1980

Histological detection of oestrogen receptor in human breast carcinomas.

Histological (immunocytochemical and cytochemical) methods for demonstrating oestrogen receptor within breast-cancer cells gave a positive reaction in 29 (83%) of 35 breast carcinomas. Oestrogen receptor could be demonstrated in cytoplasm and nucleus in 15, cytoplasm only in 10, and nucleus only in 4. 24 (68.5%) of the carcinomas had detectable oestrogen receptor by the dextran-coated charcoal method, and all of these were positive by histological methods. The cytochemical method gave much better results than the immunocytochemical method and showed that carcinomas contain variable proportions of oestrogen-receptor-positive and oestrogen-receptor-negative cells.

Adult↗
PubMed1980

Demonstration of carcinoembryonic antigen in human breast carcinomas by the immunoperoxidase technique.

Using an antiserum against carcinoembryonic antigen, which was free from non-specific cross-reacting antigen activity, carcinoembryonic antigen has been demonstrated in 45 out of 90 breast carcinomas by an indirect three-stage immunoperoxidase method. The presence of carcinoembryonic antigen appears to be related to good histological differentiation but not to histological type, lymph node metastasis, or recurrence within two years of primary diagnosis. It is suggested that the varying results obtained by different workers may be due to the differing characteristics of the anti-carcinoembryonic antigen serum used.

Breast Neoplasms↗
PubMed1980

Effect of prolactin on lactalbumin production by normal and malignant human breast tissue in organ culture.

To determine whether lactalbumin production by normal and neoplastic human mammary tissue is under the same control, the effect of prolactin treatment was studied in organ culture. Of 9 premenopausal normal breast samples, 6 produced lactalbumin in culture, and all 6 responded to prolactin treatment over 4 days. One biopsy of pregnant breast tested also responded to prolactin treatment, producing 200 times more lactalbumin in culture than did normal breast. Two of 4 normal postmenopausal biopsies produced lactalbumin, and one increased synthesis and release after prolonged exposure to prolactin. Of 10 scirrhous carcinomas, 6 produced lactalbumin, but none responded to prolactin treatment. In 2 premenopausal patients, normal breast tissue responded to different concentrations of prolactin, which were without effect on malignant tissue from the same breast. In summary, lactalbumin production in the samples that we have studied can be stimulated in normal but not in malignant breast tissue. This may indicate an absence or deficiency of prolactin receptors in malignant tissue.

Breast↗
PubMed1979

The demonstration of alpha lactalbumin in human breast carcinomas.

Alpha lactalbumin, a good marker of functional differentiation, has been demonstrated in 51 of a 100 human breast carcinomas examined using the immunoperoxidase technique. There is no relationship between production of alpha lactalbumin and histological differentiation, and the absence or presence of lymph-node metastases.

Adenocarcinoma, Mucinous↗
PubMed1978

Significance of alpha-subunit HCG demonstrated in breast carcinomas by the immunoperoxidase technique.

Fifty-three breast carcinomas were examined by an indirect immunoperoxidase technique for the presence of the alpha-subunit of human chorionic gonadotrophin. Positive staining occurred in 12 (22.6%). There was no correlation between alpha-subunit production and specific histological features, but production was related to the presence of lymph node metastases and hence a poorer prognosis. The alpha-subunit could be used as a prognostic indicator in the assessment of breast carcinoma.

Breast Neoplasms↗
PubMed1975

Anaemic crisis in sickle cell disease.

Sixteen episodes of acute anaemia necessitating urgent blood transfusion have been investigated in 13 children with sickle cell anaemia. In five out of seven episodes there was evidence of increased haemolysis while in 10 out of 16 episodes a profound fall in reticulocyte count indicated marrow erythroid cell failure. Cold agglutinins active at room temperature were detected in 13 episodes, and anti-I specificity was demonstrated in 11. Warmed blood of homologous ABO and Rhesus groups was administered without complication despite difficulty with cross-matching. The exacerbation of anaemia was not due to folate lack, glucose-6-phosphate dehydrogenase deficiency or splenic sequestration, and an infectious agent appeared responsible. The degree of anaemia in homozygous sickle cell disease is usually constant during asymptomatic periods. An episode of sudden profound anaemia (anaemic crisis) may, however, result from marrow hypoplasia, an exacerbation of haemolysis, splenic sequestration, or folate deficiency.

Acute Disease↗
PubMedDate not supplied

Variability in an MHCMosa class II beta chain-encoding gene in striped bass (Morone saxatilis).

The major histocompatibility complex (MHC) class II B locus of the striped bass (Morone saxatilis) was found to contain multiple forms of the class II B gene. Seven complete MHC class II B cDNA clones were isolated and sequenced, identifying five unique allelic forms of a MHC class II B gene. Among three specimens, each representing a geographically distinct population (Chesapeake Bay, MD; Roanoke River, NC; and Santee-Cooper Reservoir, SC) extensive variability was detected in the beta 1 encoding domain, which corresponds with the functional peptide-binding region (PBR) of known MHC class II molecules. The location of variable amino acid residues in the beta 1 domains corresponds with polymorphic sites observed in other teleosts and higher vertebrates. The amino acid translated beta 2 domain encoding regions, transmembrane regions, and cytoplasmic regions of the five clones correlated well with those of known vertebrate MHC class II proteins. Seventy-one percent of the variability found within the presumed PBR encoded at the MHCMosa class II B locus corresponded with that of the PBR of a human MHC class II B gene. Overall, the Mosa sequences showed greatest similarity to the MHC class II B genes of cichlid fishes, as expected from phylogenetic relationships.

Alleles↗
PubMedDate not supplied

The accountability game.

Explore the source record for details and available documents.

Evaluation Studies as Topic↗