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Biomedical subjects

B Wilkinson

Publications and source records attributed to B Wilkinson.

7 recordsLinked to original sources
PubMed1992

Mast cell quantitation by image analysis in adult mastocytosis and inflammatory skin disorders.

Mast cell numbers were quantitated in adult cases of mastocytosis demonstrating non-diffuse perivascular and upper dermal concentrations of mast cells. Using the Leder stain and computerised video image analysis, a mean of 382 (+/- 28 SE) mast cell per mm2 were counted in the superficial dermis in skin biopsies from 30 adult cases of mastocytosis, in contrast to a mean of 43 (+/- 5 SE) mast cells per mm2 in skin biopsies from 50 inflammatory dermatoses represented by subacute dermatitis, pigmented purpuric dermatosis, erythema multiforme, lichen planus and granuloma annulare. Ten skin biopsies showing no significant inflammation had a mean of 54 (+/- 7 SE) mast cells per mm2 in the upper dermis. The mean area of individual mast cells as assessed by image analysis in the mastocytosis group was 47.40 microns 2 (+/- 2.26 microns 2, SE) which was significantly different (P < 0.01) than the mast cell area (32.34 microns 2 +/- 2.22 microns 2, SE) in all other groups combined. Computerised video image analysis represents an alternative technique which is useful in assessing mast cell numbers and particularly mast cell size in adult cases of macular mastocytosis and in other dermatoses.

Adult↗
PubMed1988

A survey into the respiratory effects of prolonged exposure to pulverised fuel ash.

Previous studies of respiratory disorders in workers exposed to pulverised fuel ash (PFA) have been confined to radiological effects that were found to be minimal. The present survey included 268 men (88% of the defined population) with a history of more than 10 years exposure to PFA in six power stations in the south east of England. Respiratory questionnaires with full occupational histories were obtained from all of these subjects, of whom 207 were actively employed and 61 had retired; 243 had lung function tests and 208 had chest x ray examinations. The men were grouped, using their occupational histories, into high, medium, and low exposure categories. Dust concentrations were obtained by personal sampling on a representative sample of men from the three exposure categories. Lung function tests showed that a modest effect on forced vital capacity, vital capacity, forced expiratory volume in one second, peak flow, and gas transfer (DCO) was associated with prolonged heavy exposure to PFA. The men with prolonged heavy exposure also showed higher prevalences of respiratory symptoms. No definite relation between exposure and x ray changes was established. The results of this cross sectional survey indicate that exposures to PFA should not exceed the limits recommended by the Health and Safety Executive for low toxicity dusts.

Adult↗
PubMed1986

Transformation of Aspergillus nidulans with a cloned, oligomycin-resistant ATP synthase subunit 9 gene.

An allele (oliC31) of the A. nidulans oliC gene has been cloned using homology with the equivalent gene from N. crassa. OliC31 codes for an oligomycin-resistant, triethyltin-hypersensitive form of subunit 9 of the mitochondrial ATP synthase complex. Direct selection for oligomycin-resistance was possible following transformation of A. nidulans with the oliC31 gene. The phenotypes of transformants cultured in the presence of oligomycin were indicative of the position of integration of the transforming plasmid within the genome. Subsequent recombination events involving the integrated oliC31 gene were also apparent from altered levels of resistance to oligomycin or triethyltin. This gene should prove useful as a marker for transformation of strains lacking auxotrophic lesions and in gene replacement or disruption experiments.

ATP Synthetase Complexes↗
PubMed1986

Human placental conditioned medium contains monocyte-derived recruiting activity (MRA).

Monocyte-derived recruiting activity (MRA) stimulates the release of granulopoietic colony-stimulating factors (CSF) by endothelial cells. We carried out studies designed to test the hypotheses that human placental conditioned medium (HPCM), a widely utilized source of CSA for in vitro studies, contains both MRA and CSA and that these molecules could be separated on the basis of their isoelectric points. In five separate studies, concentrated samples of HPCM were chromatofocused and fractions tested in bioassays for MRA and CSA. We found that HPCM contains both MRA and CSA, that the majority of the MRA eluted at a pH of from 7.6 to 8.2 and was 2000-fold purified. CSA eluted at pH 5.6 or below. No CSA was detectable in the major MRA peak. We conclude that HPCM contains heterogeneous granulopoietic activities, that the isoelectric points of MRA and CSA are substantially different and that chromatofocusing provides a rapid single-step method for separating these two distinct granulopoietic factors from complex conditioned media.

Colony-Stimulating Factors↗