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Biomedical subjects

R W Brown

Publications and source records attributed to R W Brown.

At least 109 records · Page 6Linked to original sources
PubMed1991

The pathologist's workstation. Issues and an early prototype.

The role of a pathologist demands the efficient collection, processing and communication of information. Although computerization has been readily adopted in the laboratory to help with specimen processing, educational programs and technological tools for the pathologist's own information handling are at the inception stage. Many pathologists feel their role as a consultant would be enhanced by easy-to-use microcomputer information tools linked to their laboratory databases. This article provides an overview of emerging computer science trends and reviews areas in which a workstation is likely to be useful to the pathologist. A currently operational project embodying some of these concepts is described.

Clinical Laboratory Information Systems↗
PubMed1990

Single lung transplantation for primary pulmonary hypertension.

Single lung transplantation has become a therapeutic option for end-stage interstitial lung disease and obstructive lung disease. Our group recently extended this treatment to three patients with primary pulmonary hypertension. All patients had marked decreases in pulmonary artery pressures and pulmonary vascular resistance and increases in cardiac output following single lung transplantation. Spirometry, lung volumes, and diffusion capacity were not different in comparison to preoperative studies. Quantitative ventilation-perfusion scans revealed the majority of perfusion distributed to the transplanted lung, with ventilation approximately equally divided between the native and the transplanted lung. Despite ventilation-perfusion imbalance, there was no resting hypoxemia and there was no arterial oxygen desaturation with exercise. One patient expired on the 30th postoperative day due to cytomegalovirus infection of the lungs. In the remaining two patients, maximum exercise capacity following transplantation was near normal in one recipient and reduced in the second recipient. Of note, there was no evidence of ventilatory limitation or impaired oxygenation during exercise in these two recipients. Although an exaggerated exercise ventilatory response was present, this did not limit exercise performance. This report supports the use of single lung transplantation for the treatment of primary pulmonary hypertension.

Adult↗
PubMed1990

Immunization against recombinant bovine inhibin alpha subunit causes increased ovulation rates in gilts.

Immunization of gilts in a commercial piggery against a fusion protein of the alpha subunit of bovine inhibin, produced by recombinant DNA methods, resulted in mean ovulation rate increases of 35% at the oestrus at which, under the piggery's management practices, they would have been mated. Sera from two immunized groups showed mean binding of 6.6% and 4.9% when assayed, at 1:800 final dilution, against iodinated bovine inhibin (Mr 31,000). Ovulation rates of immunized gilts were highly correlated with the ability of serum to bind iodinated native inhibin (r = 0.62; P less than 0.001), particularly when weight and age were included in the correlation (r = 0.72; P = 0.001), and inhibin binding accounted for 38% of the total variation in ovulation rate. Immunization caused no deleterious effects on growth rate or onset of oestrus. These results demonstrate the potential for use of such immunization to increase prolificacy in gilts and young sows.

Animals↗
PubMed1989

Immunisation against the amino-terminal peptide (alpha N) of the alpha 43 subunit of inhibin impairs fertility in sheep.

Processing of the 58 kDa to the 31 kDa form of inhibin (Inh) involves cleavage of the amino-terminal peptide (alpha N) from the alpha 43-subunit. We show that active immunisation of female sheep against a recombinant bovine alpha N impairs their fertility. In Exp 1, 5 treated (Group 1; 300 micrograms alpha N) and 6 control ewes (Group 2; adjuvant only) were immunized (Day 1) and given boosters on Days 22 and 56. In Group 1, mean +/- SEM binding of 125I-31 kDa Inh was less than 0.5% on Days 33 and 44, whereas binding of 125I-58 kDa Inh was 4.9 +/- 0.7 and 6.2 +/- 0.6%, respectively. In Group 2 binding of both tracers was less than 0.5%. The corpora lutea (CL)/ewe in Group 1 on Days 44 and 82 were 1.8 +/- 0.2 and 2.8 +/- 0.9, respectively, and were not different from those in Group 2 (1.7 +/- 0.3 and 1.5 +/- 0.2, respectively). One ewe in Group 1 versus 5/6 ewes in Group 2 were diagnosed pregnant. In Exp 2, 18 treated and 16 controls were immunized as in Exp 1. The binding of 125I-58 kDa Inh in treated ewes (2.4 +/- 0.3%) was greater than in controls (less than 0.5%) on Day 56. The CL/ewe in treated ewes (1.8 +/- 0.2) was similar to that in controls (2.0 +/- 0.1) on Day 76. All 16 control ewes but only 7/17 treated ewes were subsequently diagnosed pregnant. The plasma progesterone concentrations were similar in treated ewes which did (7.6 +/- 1.2 nmol/L) and did not (7.0 +/- 0.7) become pregnant. Neither basal nor GnRH-stimulated concentrations of LH, nor basal concentrations of Inh differed between treated and controls in Exp 2. Similarly, there were no differences in FSH, except that basal concentrations were higher in the luteal phase of treated ewes. We conclude that immunisation of ewes against alpha N results in a significant reduction in fertility.

Animals↗
PubMed1989

Clinical and analytical evaluation of different methods for measurement of creatine kinase isoenzyme MB.

We evaluated the clinical and analytical performance of the new immunochemiluminometric assay (ICMA; Ciba Corning) for measurement of creatine kinase isoenzyme MB (CK-MB), and compared it with three other methods: immunoradiometric assay (IRMA; International Immunoassay Labs); immunoinhibition assay (Seradyn); and an immunoinhibition/column method (Du Pont). Intra-test precision for all kits was good. We evaluated 32 patients' samples by all four methodologies. Only one of the four methods (aca, Du Pont) showed evidence of linearity. Efficiency in the diagnosis of myocardial injury in our study ranged from 53% (Seradyn) to 96% (Du Pont). We evaluated serial specimens from 20 separate patients by the IRMA and the ICMA to determine whether myocardial injury could be diagnosed earlier by the ICMA. In patients with acute myocardial infarction, the ICMA displayed positive values earlier and longer than the IRMA, suggesting that the ICMA is suited for screening for myocardial damage in hospitalized patients.

Adult↗
PubMed1989

Hypermedia in pathology--the Dartmouth Interactive Medical Record project.

Hypermedia and hypertext are the focus of intense interest in multiple disciplines in medicine, particularly pathology. This communication provides explanation of theories and applications that serve as motivation for the expansion of use of these technologies. The Dartmouth Interactive Medical Record (IMR) project is discussed.

Humans↗
PubMed1988

Antibody response to outer-membrane antigens of Pseudomonas aeruginosa in human burn wound infection.

There is little information about the local and systemic antibody response to surface antigens of bacteria growing in situ in infected lesions in man. In this study, Pseudomonas aeruginosa was obtained directly from the infected wounds of two patients with burns and studied without subculture. Outer-membrane proteins (OMPs) were investigated and compared with those of cells cultivated in the laboratory, with the aim of selecting defined growth conditions to give surface antigens more closely resembling those found in vivo. Several high-mol. wt (77,000-101,000) proteins were expressed in the outer membranes of the bacteria from the patients and could be phenotypically induced by cultivating the same isolate in iron-depleted conditions in vitro. Other major OMPs (D, E, F, G and H) were also observed in cells taken from the lesions. Immunoblotting demonstrated that proteins D and E were recognised by different classes of immunoglobulins in the sera of both patients as was flagellar antigen present in the outer-membrane preparation of the P. aeruginosa from patient 1. Iron-regulated membrane proteins (IRMPs) were similarly detected, but more strongly by IgM from patient 1. Furthermore, a marked antibody response to IRMPs was noted at the site of infection. Bands of a similar intensity were seen after absorption of the sera with lipopolysaccharide (LPS) purified from the infecting strain. This indicated that the response observed was directed against OMPs (including IRMPs) and not against contaminating LPS.

Antibodies, Bacterial↗
PubMed1987

Immunization against an inhibin subunit produced by recombinant DNA techniques results in increased ovulation rate in sheep.

Seven Merino-Border Leicester cross-bred ewes were immunized with a purified fusion protein, produced by recombinant DNA methods, of the alpha subunit of bovine inhibin. Four animals were immunized with the fusion protein alone and three with a conjugate made by coupling the fusion protein to keyhole limpet haemocyanin (KLH) using glutaraldehyde. Each animal received four injections of the fusion protein over 93 days. The animals were synchronized using progestagen sponges and subjected to laparoscopy for the determination of ovulation rates in two consecutive cycles (days 115 and 135). The immunized animals had overall mean ovulation rates for each cycle of 3.4 and 3.4 which was significantly (P less than 0.001) above the rates of 1.1 and 1.4 determined for the controls, which had either received no treatment (n = 5) or had been immunized with 300 micrograms KLH (n = 4). Analysis of antisera taken on day 115 showed significant fusion protein antibodies and iodinated inhibin-binding capacity in the test but not control groups. Furthermore, antisera to the fusion protein in four out of seven ewes neutralized the inhibin bioactivity of ovine follicular fluid in an in-vitro bioassay. These data demonstrate that neutralization of inhibin can be effected by immunization with bovine inhibin alpha subunit and that such immunization results in increased ovulation rates as predicted from the biological role of inhibin as a suppressor of FSH.

Animals↗
PubMed1987

Multiple simultaneous percutaneous needle biopsy (MSPNB) technique for masses of the abdomen and peritoneum.

A technique for the biopsy of abdominal masses consisting of the simultaneous insertion of multiple needles is described. This technique was employed in 45 patients. The results were compared with the author's preceding experience with 32 cases performed with a conventional technique of sequential biopsies. Adequate specimens were obtained in 42 (93.3%) cases with the multiple simultaneous percutaneous needle biopsy (MSPNB) technique. This compares with a diagnostic adequacy yield of 84.3% for the sequential technique. In 25 cases performed under CT guidance, the average CT utilization time was 12 minutes, and the average number of slices was 3, as compared to 45 minutes and 12 slices with the conventional sequential technique. No complications were encountered. We conclude that the MSPNB technique is a safe time- and cost-effective technique with a high yield of adequate and diagnostic specimens.

Abdominal Neoplasms↗
PubMed1986

A monoclonal antibody CIBr17 recognizes a myoepithelium-specific antigen in human mammary gland.

A murine monoclonal antibody (MAb) CIBr17, raised against the human breast carcinoma cell line PMC42, reacts specifically with myoepithelial cells in normal human breast. This IgGl antibody recognizes a approximately 110kDa glycoprotein that is expressed on the cell surface and junctional membranes of PMC42 monolayer cultures. The CIBr17 antigen is present in two major glycosylated forms with approximate pls of 5.2 and 5.5 respectively in PMC42 cells. The tissue specificity of CIBr17 was assessed on frozen sections of PLP-fixed tissues by means of a 4-layer immunoperoxidase technique. CIBr17 has reacted with a variety of epithelium-derived tissues and some smooth muscle cells. Within many epithelial tissues, CIBr17 has demonstrated specific staining of particular epithelial cell types. Within normal breast and most benign breast lesions, antibody CIBr17 stained only myoepithelial cells. No staining of luminal epithelium, basement membranes or stromal elements was observed. In sclerosing adenosis, CIBr17 stained areas of pronounced myoepithelial differentiation, while in duct epitheliosis variable staining of proliferating cells was observed. In breast carcinomas, CIBr17 demonstrated variable antigen expression. In most tumors, CIBr17 either did not stain any tumor cells or stained only a small number of tumor cells spread randomly throughout the tumor. In several ductal carcinomas, however, CIBr17 stained the majority of tumor cells.

Antibodies, Monoclonal↗
PubMed1986

Cloning and sequence analysis of cDNA species coding for the two subunits of inhibin from bovine follicular fluid.

The primary amino acid structures of the 43-kDa (A) and 15-kDa (B) subunits of the 58-kDa form of the hormone inhibin have been elucidated by cloning and analysis of cDNA species derived from bovine granulosa cell mRNA. The A subunit (Mr = 32,298) is a protein of 300 amino acids with two potential N-glycosylation sites and two potential proteolytic processing sites and has a pre-pro region of 60 amino acids. The mature B subunit (Mr = 12,977) is a protein of 116 amino acids synthesized from a separate mRNA. These data establish that a 31-kDa form of inhibin also isolated from bovine follicular fluid, with subunits of 20 kDa (Ac) and 15 kDa (B), is derived from the 58-kDa form by proteolytic processing of the A subunit.

Amino Acid Sequence↗
PubMed1986

Development of monoclonal antibodies to the human breast carcinoma cell line PMC42.

In an attempt to identify antigens expressed during breast differentiation, three murine monoclonal antibodies, CIBr2, CIBr7, and CIBr18, were produced against the human pleomorphic breast carcinoma cell line PMC42. All three monoclonal antibodies reacted with previously undescribed antigenic determinants on the PMC42 cell line. Antibody CIBr18 reacted only with the immunizing cell line PMC42, whereas antibodies CIBr2 and CIBr7 showed minimal reactivity toward a panel of 34 human leukemia- and solid tumor-derived cell lines. The antigenic determinants detected by the three antibodies were distinct, and each showed variable expression in PMC42 monolayer and organoid cultures. The heterogeneity of staining seen on PMC42 cultures may reflect the fact that this cell line contains up to eight morphologically distinct cell types. Antigen expression correlated with cell type in some instances, whereas in other instances phenotypic subdivision within a cell type was apparent. Antigens recognized by antibodies CIBr7 and CIBr18 were characterized biochemically. In Western blotting, antibody CIBr7 identified a single band of an apparent molecular weight of 38,000 within PMC42 cell lysates. Sodium dodecyl sulfate-polyacrylamide gel analysis of polypeptides immunoprecipitated by antibody CIBr18 from [35S]methionine-labeled PMC42 cell lysates identified two glycoproteins of apparent molecular weights of 115,000 and 120,000, respectively. No biochemical data for the CIBr2 antigen are yet available. All three antigens were detected in human mammary epithelium and some non-breast tissues. The expression of these antigens in normal and neoplastic mammary epithelia is discussed in terms of antigen heterogeneity and changes in antigen expression upon conversion to the malignant state.

Adult↗
PubMed1985

Gaucher's disease affecting the mandible.

A case of Gaucher's disease affecting the left body of the mandible is presented. Dentists can recognize this uncommon disease through the medical history of the patient, the presence of characteristic Gaucher cells on biopsy of the lesion, and decreased serum levels of the enzyme glucocerebrosidase.

Gaucher Disease↗
PubMed1985

Facial nerve injury during surgery of the temporomandibular joint: a comparison of two dissection techniques.

Changing the dissection technique for gaining access to the temporomandibular joint decreased the incidence of facial nerve injury from 25% to 1.7%. This decrease can be attributed to the elimination of both development of a skin flap and dissection of tissue overlying the lateral capsule. Normal anatomic variation in the distribution of facial nerve branches may relate to the incidence of clinically apparent injury.

Dermatologic Surgical Procedures↗
PubMed1985

Frequency of benign and malignant breast lesions in 207 consecutive autopsies in Australian women.

A histopathological study was undertaken on breast tissue dissected during the course of 207 consecutive forensic post-mortems on women over the age of 15 years in order to define the frequency and types of lesions found in Australian women. At least 10 blocks were obtained from each breast and a total of 4,738 blocks were examined. A particularly high frequency of atypical hyperplasia (12.6%), carcinoma in situ (13.0%), focal secretory change (24.1%) and perilobular haemangiomas (11.2%) was found. The radial scar, considered by some to be a precursor of infiltrating ductal carcinoma was found in 7.7% of the women.

Adolescent↗