PubMed HealthSearch

Biomedical subjects

S Goyal

Publications and source records attributed to S Goyal.

6 recordsLinked to original sources

Phospholipid composition and subcellular distribution in yeast and mycelial forms of Candida albicans.

Lipids were found to constitute 3.9% and 4.7% of the dry weight of yeast and mycelial forms of Candida albicans, respectively. Phospholipids were localized mainly in the microsomal fraction of both growth forms and phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine and cardiolipin were the major phospholipids. Myristic acid and palmitic acid were the predominant fatty acids in the yeast form while the mycelial form contained palmitic, palmitoleic and oleic acid as major fatty acids. Yeast forms showed significantly higher specific activities of intracellular phospholipase A and lysophospholipase when compared with mycelial forms. No significant difference in the specific activity of extracellular phospholipase A was seen in either morphogenic form while the activity of extracellular lysophospholipase was higher in the yeast form. These results are discussed in the context of the virulence of this fungus.

Candida albicans

Elevated plasma histamine in chronic uremia. Effects of ketotifen on pruritus.

A role for histamine in the pathogenesis of uremic pruritus was investigated in maintenance hemodialysis patients. Venous plasma histamine levels, as determined by radioenzymatic assay, were significantly higher (p less than 0.05) in hemodialysis patients with pruritus (368 +/- 103 pg/ml [mean +/- SEM], n = 6) than in those without pruritus (146 +/- 22 pg/ml, n = 5) and in normal controls (142 +/- 16, n = 5). Arteriovenous fistula histamine levels (202 +/- 52 pg/ml, n = 6) were significantly lower (p less than 0.05) than simultaneously drawn venous samples. Markedly elevated histamine-degrading enzyme (histaminase) activities were found in both hemodialysis patients with (2.95 +/- 0.18 pg histamine degraded/minute) and without (2.44 +/- 0.28) pruritus, but was undetectable in normal controls. Histaminase activities did not significantly differ in simultaneously drawn venous and fistula samples. With hemodialysis, histaminase activities fell significantly (p less than 0.01), whereas plasma histamine did not change. We further examined the effects of ketotifen, a putative mast cell stabilizer, on severe uremic pruritus. Five of five patients had significant (p less than 0.01) reductions in pruritus, as judged on a six-point pruritus index, after 8 weeks of drug (x = 2.3), as compared to conventional therapy (x = 5.9). Despite these improvements, no significant differences were noted in pre- versus post-drug plasma histamine levels, histaminase activities, or the histamine content per gram of skin biopsy specimen. These data support prior hypotheses that mast cell activation contributes to the pruritus of uremia.

Chronic Disease

Phosphorylase activity as a histochemical marker of specialized tissue of heart.

Phosphorylase activity has been investigated histochemically under controlled conditions in the specialized tissue and the general myocardium of goat heart using glucose-1-phosphate as the substrate. It has been observed that the phosphorylase content of the nodal and conducting tissue is very high as compared to the general myocardium. The phosphorylase content of the cardiac neural elements is also high. Since the connective tissue which surrounds the nodal and conducting tissue has almost no phosphorylase activity, the nodal and conducting tissue is sharply demarcated by the histochemical reaction for phosphorylase. This reaction can, therefore, be used as a specific and expedient method for the localization of specialized tissue as an exploratory and confirmatory test.

Animals