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Biomedical subjects

G Wilson

Publications and source records attributed to G Wilson.

At least 271 records · Page 15Linked to original sources
PubMed1983

Perceptual imprinting: genetic influences and genotype-environment interactions.

One-day-old visually naive and experienced quail chicks (C. coturnix japonica) were mass-screened for approach preferences by pairs of stimuli that were identical in size and luminance but different in color, or pattern, or both color and pattern. Subjects were drawn from the 18th generation of quail lines that were bidirectionally selected for color preferences, and from an unselected genetic control line. Experience consisted of 12 hr of unreinforced perceptual exposure to colored or white stimuli, with and without associated pattern. Data indicated strong genetic influences in the preferences of exposure to color and pattern resulted in selective learning of color but not pattern. Systematic variations in postexposure choices between composite stimuli of colors and pattern. Systematic variations in postexposure choices between composite stimuli of colors and patterns were traced to variations of genotype, experience, and genotype-experience interactions.

Animals↗
PubMed1983

Toxicology of brominated fatty acids: metabolite concentration and heart and liver changes.

Rats were fed for 35 days diets containing 2% of either brominated corn oil (BCO), monoglyceride of dibromostearate (DBS), monoglyceride of tetrabromostearate (TBS) or a mixture of the two monoglycerides (BMG) which provided proportions of brominated acids comparable to that of the BCO. Hearts from all animals fed BCO were yellow colored and firm in texture. Myocardial cellular degeneration, mild to moderate edema and occasional small necrotic foci were observed. Hearts from animals fed DBS showed moderate edema and some slight necrosis. All diets produced an increase in lipid content of heart. Animals fed the experimental diets developed enlarged livers and showed elevated liver lipid content. The tetrabromostearate appeared to be the more active in producing these changes, in particular a severe intracellular fatty degeneration. Shorter-chain (C-16, C-14) metabolites of di- and tetrabromostearate were identified and the concentration of brominated fatty acids in heart, liver and adipose tissue determined and found to account for 80% of the bromine detected in these tissues by neutron activation analysis. TBS accumulated in liver while the highest concentration of DBS was observed in heart lipids. Although the concentrations of brominated acids in heart and liver lipids were comparable in rats fed BCO or BMG, BCO produced the more pronounced effects. This differential could be due to additional active components in BCO or to a variation in response associated with changes in the location of the fatty acid on the glycerol molecule.

Adipose Tissue↗
PubMed1983

The effect of alcohol on the visual and ocular motor systems.

Alcohol is generally considered to be a central nervous system (CNS) depressant. This effect is progressive from higher cortical centres through to fundamental body functions. The effect of alcohol ingestion on the visual and ocular motor systems of ten healthy subjects was the basis of this study. Significant changes in the following resulted from the ingestion of 0.375 g/kg of 10% ethanol alcohol: prism measurements of deviations for near and distance, ocular movements, convergence near point, and visual acuity at six metres. No significant change was observed following testing of stereopsis or near visual acuity.

Adult↗
PubMed1983

Venous obstruction. A potential complication of transvenous pacemaker electrodes.

Pervenous endocardial pacing using a self-contained, totally implantable system was popularized in this country by Chardack in 1965 and subsequently has become the established mode of permanent pacing. Although this intervention may be lifesaving, it is not without risk. Occlusion of major vessels incited by the presence of a pacing electrode is an extremely rare occurrence. We describe four patients who had occlusion of the axillary or subclavian veins or of the superior vena cava due to pervenous pacing electrodes. We review the literature of previous observation of venous occlusion and thromboembolic complications due to pervenous pacemakers, describe the clinical features accompanying venous obstruction, and review pathophysiology and proposals for treatment. The use of noninvasive radionuclide venography serves as a useful adjunct in the diagnosis of venous obstruction from pacing catheters.

Aged↗
PubMed1983

Stages in specialization of fibroblast adhesion and deposition of extracellular matrix.

Fibroblast cells seeded on a serum glycoprotein shown previously to mediate a spread shape without focal adhesions or microfilament bundles (Stage 1 spread) are now shown to have substratum contacts in which coated pits are abundant and associated with small globular deposits of glycocalyx bridging to substratum and staining for fibronectin and acidic glycoconjugates. After stimulation with serum or fibronectin to form focal adhesions and microfilament bundles (Stage 2 spread), clathrin-based structures remain at the cell underside but no longer in conspicuously higher concentration than on the dorsal surface; extracellular material at adhesions is now as regular strands which stain for acidic glycoconjugates but (as reported earlier by Chen and Singer) not always for fibronectin. During these stages of adhesion, striking changes are seen in the cellular display of fibronectin monitored by immunofluorescence. In rounded cells this is granular and cytoplasmic, concentrated around the submembranous cortex; on spreading to Stage 1, it remains granular and intracellular but is now oriented strongly towards the lower cell surface; only in Stage 2 does externalisation proceed to deposit fibrillar fibronectin on the substratum. While cytoplasmic orientation of matrix precursors can be determined by cell contact, organised externalisation is therefore coupled to fully developed adhesion status.

Animals↗
PubMed1983

The relation between eyelid tension, corneal toricity, and age.

It has been demonstrated that corneal toricity can be altered by lifting the lids from the surface of the eye. Thus, corneal curvature is modified by the position or tension of the lids. Does it follow that differences in lid tension between individuals are related to variations in corneal toricity? A lid tensiometer was designed that measured the force exerted by a lid as it was pulled away from its resting place on the eye. When this force was plotted as a function of the displacement of the lid, an elastic coefficient of the lid was obtained. This elastic coefficient was used to denote lid tension. In a sample of 195 eyes, the elastic coefficient of the lid had a mean of 3.22 g/mm (SD +/- 1.12), with a range from 1.16 to 6.78 g/mm. The results showed no correlation between the elastic coefficient and corneal toricity. Both the elastic coefficient and with-the-rule corneal toricity showed a statistically significant decrease with age. However, there was no significant relation between the elastic coefficient and corneal toricity when the effect of age was ruled out. From this experiment, and a reading of the literature, we conclude that there is no experimental evidence to show that lid tension determines corneal toricity.

Adult↗
PubMed1982

Tissue fatty acid changes and tumor incidence in C3H mice ingesting cottonseed oil.

The incidence of spontaneous mammary tumors in C3H mice at 35 wk was higher in mice fed rations containing cottonseed oil than in mice fed fats of comparable fatty acid composition. The time to 50% (T50) incidence was also shorter in the first group. The fatty acid composition of tissue lipids from mice fed the cottonseed oil showed changes indicating the presence of cyclopropene fatty acids-higher levels of saturates and lower oleate/stearate and palmitoleate/palmitate ratios. A possible association between the development of a spontaneous mammary tumor in the C3H mouse and the presence of cyclopropene fatty acids in the cottonseed oil is indicated.

Animals↗
PubMed1982

The effect of lifting the lids on corneal astigmatism.

Corneal toricity was measured using a keratometer with the lids in the normal position, and with the lids retracted. Lid retraction usually changed the measured toricity. In corneas with more than 1.00 D of with-the-rule astigmatism, the change was in the direction of less with-the-rule astigmatism. In corneas with astigmatism between 1 D with-the-rule and 1 D against-the-rule, the change was not systematic. The results compare with the original experiment of Masci (1965), who also found that corneas with more with-the-rule toricity show a greater reduction in toricity when the lids are retracted. Clearly the pressure the lids exert on the eyeball is a major factor influencing astigmatism.

Adolescent↗
PubMed1982

Conservative coloprotectomy for the sexually active woman.

The procedure described herein, capitalizes on a knowledge of the relationships between the pelvic viscera, its autonomic innervation and its tissue support. Operative time is shorter, not only because of the presence of a simultaneous second surgical team, but also because the improved exposure and use of bloodless planes facilitates dissection and reduces blood loss. The careful treatment of the cul-de-sac peritoneum helps protect the autonomic innervation of the pelvis, preserving the function of the bladder and sexual response. Preserving the perineal body and obliterating the dead space behind the posterior vaginal wall with the levator ani muscle provides a muscular cushion for the vagina, preserving maximum coital function. For the woman who is sexually active, these are important goals. Her improved sense of well-being following successful surgical therapy of the disease will result in increasing libido, and her successful adaptation to her new condition will be influenced favorably by her ability to function sexually.

Coitus↗