ABSTRACT
The effects of octenidine and pirtenidine on yeasts (in particular Candida albicans) have been studied. MIC and MCC values have been established as well as the inhibitory effects on growth, budding and germ tube formation. The drugs were shown to cause extensive leakage of cytoplasmic contents from the cells which was correlated with morphological and ultrastructural changes in the yeast.
Subject(s)
Aminopyridines/pharmacology , Antifungal Agents , Fungi/drug effects , Pyridines/pharmacology , Candida/drug effects , Candida/growth & development , Candida albicans/drug effects , Candida albicans/growth & development , Candida albicans/ultrastructure , Fungi/growth & development , Fungi/ultrastructure , Imines , Microbial Sensitivity Tests , Microscopy, Electron , Microscopy, Electron, Scanning , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae/growth & developmentABSTRACT
In vitro culturing of three different yeast species with a number of glucocorticoids altered their adherence ability in two ways: Incubation with dexamethasone and triamcinolone acetonide promoted the adherence in general (the increase in adherence ranged between 17% and 44%), whilst growth in the presence of cortisone acetate or hydrocortisone blocked the adherence (inhibition ranged from 16% to 32%). No statistical difference in the adherence capabilities of different growth phases of C. albicans noted, and the effects of glucocorticoids persisted irrespective of the phase of growth used. An attempt to explain the differences in adherence of the Candida spp. investigated, in the presence of various steroids, on the basis of variation in their structural configurations and/or steroid-receptor interaction is given.
Subject(s)
Candida/physiology , Glucocorticoids/metabolism , Mouth Mucosa/microbiology , Adhesiveness , Candida/growth & development , Candida/metabolism , Cortisone/analogs & derivatives , Cortisone/metabolism , Dexamethasone/metabolism , Epithelium/microbiology , Humans , Hydrocortisone/metabolism , Triamcinolone/metabolismABSTRACT
Lipids extracted from Candida albicans and C. tropicalis, but not from the weakly adherent C. pseudotropicalis, significantly blocked in vitro adherence of the respective yeast cells to buccal epithelial cells. The percentage of reduction from control values ranged between 16.4 and 42.1%, depending on the species, the strain, and the solvent used for lipid extraction. The constituent lipid classes of both the acetone and chloroform-methanol extracts of C. albicans ATCC 10231 were qualitatively and quantitatively analyzed. The individual classes were isolated by preparative thin-layer chromatography and then tested for their effects on the adherence of this strain to buccal epithelial cells. Individual phospholipids, sterols, and steryl esters blocked adherence significantly (between 15.5 and 55.7% reduction). Triacylglycerols and free fatty acids showed no effect whatsoever. The same results were obtained when standard lipid samples were investigated.
