Biomedical subjects

S J Clark

Publications and source records attributed to S J Clark.

153 records · Page 9Linked to original sources

PubMed1977

In-vitro metabolism of [3H]testosterone by scalp and back skin: conversion of testosterone into 5alpha-androstane-3beta, 17beta-diol.

The in-vitro metabolism of [3H]testosterone by human scalp and back skin was examined for possible differences in enzyme activity in skin from these two areas, both of which contain large sebaceous glands but only one of which, the back, is prone to develop acne. Punch biopsy specimens of skin, obtained from the scalp and back of adult men, were minced and incubated with [3H]testosterone. The metabolic products were diluted with carrier steroids, then separated and measured by thin-layer chromatography and by gas chromatography on an instrument equipped with a splitter. The results showed that of the 5alpha-reduced metabolites identified, a major one in both the scalp and back skin incubations was 5alpha-androstane-3beta,17beta-diol. Formation of the androstanediol was especially pronounced in scalp skin where it accounted for up to 50% of the 5alpha-reduced metabolites produced. This finding that 5alpha-androstane-3beta,17beta-diol is a major product of testosterone metabolism in vitro by human skin containing sebaceous glands, supports the possibility, previously suggested by studies in the rat, that this steroid can stimulate sebum secretion.

Androstane-3,17-diol↗

PubMed1976

Pathogenesis of aqueductal occlusion in congenital murine hydrocephalus.

In a study of congenital hydrocephalus in the murine mutant (hy-3/hy-3), the authors found that aqueductal stenosis develops during the progression of hydrocephalus. In Stage 1 hydrocephalus (ventricular dilation and open aqueduct), a block in the subarachnoid space over the cerebral convexities causes the lateral and third ventricles to enlarge. The ependyma becomes stretched and a collection of edematous fluid forms in the subependymal layer. In Stage 2 hydrocephalus (edema in white matter around lateral ventricles and compression of quadrigeminal plate), edema develops peripheral to ependyma in the aqueduct and compresses the lateral surfaces of the aqueductal wall to obstruct the lumen. While periaqueductal edema is spreading, the forces of the expanding midline structures and the cystic occiital horns alter the relationship of brain structures. There is no proliferation of glia, but, rather, a "simple stenosis" which results from a combination of ventricular dilation, cerebral edema, brain shift, brain-stem compression, and brain-stem edema. In this study, normal ependymal specializations were observed that indicate a more active functional role for aqueductal ependyma than previously recognized.

Animals↗

PubMed1976

The agon motif.

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Adult↗

PubMed1976

Computerized medication monitoring system.

A computerized medication monitoring system for alerting and warning of potential adverse drug reactions is described. The system integrates computerized data on each hospital patient (medications, clinical laboratory, blood gas, ECG, ALLERGIES, DIAGNOSIs, etc.) and returns to the pharmacist warning messages and suggestions regarding patient drug therapy. The broad data base allows for nearly complete drug therapy monitoring. When a warning message is received, the pharmacist contacts the physician or nursing staff and explains the potential problem. The system also generates prescription labels and patient drug profiles which are used in a unit dose dispensing system. Five percent of 13,727 patients monitored have had drug alerts. Of these alterts, 44.9% were drug-laboratory contraindications and only 28.9% were drug-drug interactions. Of the 690 alerts received, 77% resulted in the physician changing the patient's therapy.

Computers↗

PubMed1974