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Biomedical subjects

B Wilson

Publications and source records attributed to B Wilson.

At least 163 records · Page 9Linked to original sources
PubMed1988

Cell-surface changes associated with transformation of human hepatocytes to the malignant phenotype.

Hepatocellular carcinoma is one of the leading causes of cancer death in the world. To understand the cellular changes associated with transformation of hepatocytes to the malignant state, we have made several libraries of monoclonal antibodies against the hepatocellular carcinoma cell line FOCUS and have found six antibodies (AF-20, SF-25, SF-31, SF-90, XF-4, and XF-8) that recognize antigens expressed at consistently higher levels on hepatoma cells. We have studied malignant and nontransformed liver tissue from the same individual by using direct 125I-labeled antibody binding and immunoperoxidase staining techniques. For each of these antibodies, we found striking increases in antigen expression on the transformed tissues. These antigens were found to be expressed throughout the tumor and on distant metastases, with little, if any, expression on the nontransformed adjacent liver. These antibodies demonstrate that hepatic transformation may be accompanied by stereotyped and predictable antigenic changes. The uniformity of such antigenic changes suggests an association between these cell-surface alterations and the malignant transformation process.

Antibodies, Monoclonal↗
PubMed1988

Human umbilical artery flow velocity waveforms before and after regional anesthesia for cesarean section.

The umbilical artery waveform was assessed in 18 normal nonlaboring patients before and after full surgical epidural anesthesia for repeat cesarean section. Using range-gated pulsed Doppler ultrasound, we found that the waveform analysis of the umbilical artery close to its placental insertion did not change significantly. These results suggest that no deleterious effect on fetoplacental circulation occurs with this form of anesthesia as long as maternal blood pressure is normal.

Anesthesia, Epidural↗
PubMed1988

Utility of immediate postlobectomy fiberoptic bronchoscopy in preventing atelectasis.

In a prospective randomized trial, we examined the value of routine postlobectomy fiberoptic bronchoscopy (FOB) in preventing postoperative atelectasis. Twenty patients who underwent lobectomy were randomly assigned to either chest physical therapy alone (group 1) or immediate bronchoscopy (group 2). Both group 1 and group 2 were placed on a standard physical therapy regimen consisting of aerosol bronchodilator therapy, chest percussion, and incentive spirometry. It was concluded that routine postlobectomy bronchoscopy offers no advantage over the usual physical therapy measures in preventing the development of postoperative atelectasis.

Administration, Inhalation↗
PubMed1988

Computer-assisted learning in medical education.

The advent of cheap and powerful micros has opened the possibility of computer-assisted learning (CAL) in medical education. This article attempts to demonstrate the educational value of CAL, with illustrations of its use. Four styles of CAL are examined, and the danger of trivializing the learning process discussed. The ultimate CAL package which enables students to take charge of their own learning is considered. There are considerable advantages in distance learning, self-assessment, computer-marked examinations and 'audit'. Some of the main problems are considered; these are decisions which must be taken about the choice of hardware and software. The use of various peripheral devices such as slide projectors and videodisc players greatly enhances the value of CAL material, as do alternative input devices. Some thought is given to software style in the presentation of material, and also to the question of the keeping of student records. The use of an author language facilitates program development, and the construction of content-free 'shell' programs enables new material to be added to existing frameworks. Other advantages of CAL include student access to JANET and the possibility of on-line searching of databases. CAL in medical education can help to liberate students from the burden of the rote learning of facts, and enhance the role of reason and imagination in the learning process.

Computer-Assisted Instruction↗
PubMed1987

Single-case experimental designs in neuropsychological rehabilitation.

It is becoming accepted that single-case studies can offer important contributions to theoretical aspects of neuropsychology. Such recognition has not been so forthcoming in the field of rehabilitation, where single-case studies can be employed to evaluate neuropsychological treatments. This paper describes behavioural approaches to treatment of the neurologically impaired which include single-case experimental designs that have originated in the field of behavioural psychology. Examples of behaviour programmes for the treatment of apraxia and alexia are provided together with examples of single-case experimental designs used to evaluate memory therapy. The paper concludes with a brief discussion of the role of statistics in single-case studies.

Adult↗
PubMed1987

Adenocarcinoma of the endocervix--a histochemical study.

The histological distinction between endometrial and endocervical adenocarcinoma may present diagnostic difficulties. Several reports have suggested that differences in the histochemical staining of the tumours may indicate their histogenesis. In this paper we have compared the staining properties of 20 endocervical adenocarcinomas (14 invasive and six in situ) with 12 cases of endometrial adenocarcinoma. Unequivocal examples were used where the site of origin was not in doubt. Sections were stained using a monoclonal antibody to carcinoembryonic antigen (CEA), alcian blue at pH 1.0 and pH 2.5, PAS-diastase and toluidine blue. The results were graded by two pathologists and results compared. Three poorly differentiated invasive endocervical tumours were completely negative for CEA. Seventeen out of the remaining 20 endocervical tumours and 7/12 endometrial adenocarcinomas showed a non-specific apical staining pattern. This also occurred in normal and dysplastic endocervical glands. Intense intracytoplasmic staining for CEA was found in 7/14 invasive and 3/6 in situ endocervical adenocarcinomas. Normal endocervix never showed this staining reaction. However, 4/12 endometrial tumours showed a similar pattern. Mucin stains showed no specific staining pattern for either tumour. In an individual case where the site of origin is in doubt, histochemical methods are of little value in confidently resolving the problem.

Adenocarcinoma↗
PubMed1987

Abnormal distribution of c-myc oncogene product in familial adenomatous polyposis.

Monoclonal antibodies raised by synthetic peptide immunisation were used to determine the distribution of the protein product of the c-myc gene by immunocytochemical staining of archival wax embedded material from patients with familial adenomatous polyposis. Polyps from 18 cases of familial adenomatous polyposis, 10 of whom had developed malignant change, and 30 normal control colonic biopsy specimens were examined. A consistent staining pattern was observed in normal mucosa; nuclear staining in the basal proliferative zone; mixed nuclear and cytoplasmic staining in the maturation zone; and cytoplasmic localisation in the surface mature zone. In contrast, the polyps and carcinomata showed a mixed pattern of cytoplasmic and nuclear localisation in the basal proliferative zone with nuclear persistence throughout the crypts to the surface mature zone. This abnormal distribution of the c-myc oncogene product may have a role in the evolution of polyps and their subsequent malignant transformation into familial adenomatous polyposis.

Adenomatous Polyposis Coli↗
PubMed1987

A case study of cortical colour "blindness" with relatively intact achromatic discrimination.

A patient is described whose most striking visual disorder was a grossly impaired ability to discriminate between different colours (hues) that were matched for brightness. In contrast his ability to discriminate between different neutral greys presented in the same fashion was much less abnormal, even though the greys were perceptually difficult. Although visual acuity was reduced and visual fields were constricted, and the patient's memory was moderately impaired, these associated symptoms could not themselves be the cause of his unusual colour vision. The patient had the symptoms of cerebral achromatopsia, and the relative preservation of his form vision (when his reduced acuity is taken into account) and his achromatic vision supports the view that the many different visual cortical areas recently demonstrated in the brains of monkeys, and presumed to exist in man, have a perceptual specialisation that matches their physiological differences.

Adult↗
PubMed1987

Disturbances in glomerular basement membrane glycosaminoglycans in experimental diabetes.

Glycosaminoglycans (GAGs) were purified from basement membranes isolated from glomeruli of control and streptozocin-induced diabetic rats and were quantitatively analyzed with a recently described competitive binding assay that is specific for and sensitive to microgram amounts of chondroitin and heparan sulfate. Total GAG content in glomeruli from diabetic rats and in the basement membranes prepared from these samples (17.22 +/- 1.45 and 6.56 +/- 0.49 micrograms/10(5) glomeruli, respectively was significantly less than that found in comparable control preparations (43.71 +/- 3.35 and 16.05 +/- 1.41 micrograms/10(5) glomeruli, respectively). The portion of total GAG in the water-soluble fraction recovered after osmotic lysis of isolated glomeruli was also markedly decreased in diabetic samples (26.11 +/- 4.55 vs. 3.30 +/- 0.32 micrograms/10(5) glomeruli, control vs. diabetic). Treatment of lysed glomeruli with the ionic detergent deoxycholate, required for liberation of the extracellular matrix from plasma membrane lipoproteins and purification of the insoluble glomerular basement membrane (GBM), resulted in solubilization of approximately 10% of the water-insoluble GAG in control samples but greater than 50% in diabetic membranes. Heparan sulfate comprised greater than 90% of the GAGs in both control and diabetic GBM, defined as the water- and detergent-insoluble matrix. The findings clearly demonstrate that the GAG content of GBM is diminished in experimental diabetes and provide evidence that the reduction in GBM anionic sites associated with diabetes derives from a decrease in the constituent GAGs of this extracellular matrix. The results further suggest that the interaction between GBM and populations of GAG associated with the surface of plasma membranes of adjacent cells is disturbed in diabetes.

Animals↗