Basic characteristics of the process of Candida adhesion to human epitheliocytes

The adhesion of fungi belonging to the genus Candida to the epithelial cells of the mouth cavity reached its maximum at pH 6.2-7.0. The process of adhesion had similar dynamics at temperatures of 37 degrees, 28 degrees and 25 degrees C, but the adhesive activity decreased 2 times when temperature dropped from 37 degrees to 25 degrees and 4 times when temperature dropped to 4 degrees C. The introduction of the ions Ca2+ (1 and 10 mM) and Mg2+ (10 mM) led to the increase of adhesion by 80, 100 and 24% respectively. The heating of the fungal cells at 100 degrees C (for 1 hour) and at 63 degrees C (for 2 hours) decreased adhesion to 8 and 24% respectively, and treatment with formaldehyde (for 24 hours) decreased adhesion to 70% of that observed in experiments with live Candida cells.     

Effect of enzymes on the adhesion of fungi of the genus Candida to the buccal mucosa in vitro

Influence of selected enzymes as pepsin, pronase, lysozyme, and glusulase on adhesion of 15 strains of Candida sp. to buccal epithelial cells of oral cavity of man was examined in vitro. The enzymes were used in such concentration which did not influence the viability of fungal cells. Only pepsin preincubation had no influence on adhesion test, the remaining enzymes inhibited significantly attachment of Candida strains to epithelial cells in an adherence assay in vitro.     

Adhesiveness of yeast-like fungi in the system "Candida albicans--vaginal epitheliocytes"

The influence of vaginal liquid on adhesive reactions in the system "Candida albicans - vaginal epitheliocytes". Preliminary treatment of C. albicans by mucin, natural or absorbed vaginal liquid resulted in decrease of adhesive activity (p<0.05). C. albicans did not change its adhesive properties in case of preliminary treatment of vaginal epitheliocytes by the same substances. In the system "Candida albicans - vaginal epitheliocytes" vaginal liquid has the expressed antiadhesive effect, which probably belongs to mucin.     

A cytomorphological analysis of the adhesion of fungi of the genus Candida to human and animal epithelial cells

Morphological pattern of adherence of Candida genus fungi to human and animal epithelial cells have been studied using histological and cytological methods. The interspecific differences of epithelial adhesive properties were observed: in one case, the mucous membrane epitheliocytes of different localization had different adhesive properties. Adhesive properties vary significantly within one type of epithelial cells. In individual epitheliocyte, the adherence of fungal blastospores was nonuniform: the greater density was observed in peripheral areas of cytoplasm.     

Sensitivity of fungi of the genus Candida to antifungal drugs

Seventy two Candida strains isolated from patients with candidiosis of the oral mucosa were studied with respect to their sensitivity to nystatin, levorin, decamine, ethonium, sanguiritrin and clotrimazole. At concentrations of 0.5 to 5 micrograms/ml all the Candida species i.e. C. albicans, C. tropicalis, C. krusei and C. quilliermondii were highly sensitive to clotrimazole. Fungistatic action of levorin, nystatin and sanguiritrin was observed in 91, 67 and 38 per cent of the strains respectively. The Candida strains were resistant to decamine and ethonium used in the above concentrations.     

Lysozyme activity of fungi of the genus Candida

The capacity of fungi belonging to the genus Candida to produce lysozyme was studied. All 60 strains under study were found to possess pronounced muramidase activity. Among these cultures highly active lysozyme producers were discovered, which would make it possible to use them for production purposes in future.     

Clinico-experimental study of a dried selective medium for isolating fungi in the genus Candida

The trial of a newly developed dried selective medium for the isolation of fungi of the genus Candida, involving the inoculation of 103 museum yeast strains and 542 specimens of pathological material, has been carried out. The data obtained in this trial indicate that the proposed medium has advantages over wort agar and Sabouraud medium with antibiotics in the germination index, in the ability to ensure fungal growth after the inoculation of pathological material, and in selective properties. The medium ensures the intactness of the morpho-cultural, biochemical and serological properties of the fungi. The results of the trial recommend the newly developed preparation for laboratory practice for the isolation of yeast-like fungi from clinical material in the diagnosis of candidiasis, intestinal microflora disturbances, as well as for isolation of the fungi from various environmental objects.     

Search for biological remedies for fungi of the Candida genus

51 bacterial strains were studied with a view to find out anticandidial activity; of these, 15 strains were found to have activity, more on less expressed with respect to fungi of the genus Candida. In most cases the anticandidial activity of an antagonist strain was manifested to a similar degree against several Candida strains. The preliminary analysis of antifungal substances produced by microbial strains makes it possible to suggest their antibiotic nature.     

Changes in the adhesion of Candida fungi to the epithelium during the menstrual cycle

Changes in the adhesion of Candida cells to the mucous membrane of the oral cavity were studied in vitro in experiments with epithelial cells from 12 normal women at various stages of the menstrual cycle. Fungal cells more actively adhered to the epithelial cells obtained at the follicular phase of the menstrual cycle than to those obtained at its luteal phase. At the follicular phase, both the average level of adhesion and the population of epithelial cells with most pronounced adhesive properties increased. The range of variations in adhesion levels was different in individual subjects and varied from 8% to 37% of the individual mean of the whole cycle. The results of this study indicate the existence of the hormonal control of the adhesion of Candida cells to human epithelial cells.     

Distribution of epitheliocytes by the number of Candida albicans adhered to them and assessment of the intensity of the adhesion in an in vitro test

The study of the adhesion test in suspensions, carried out with 9 C. albicans strains and human buccal epithelial cells, has revealed that these cells are exponentially distributed by the number of C. albicans cells adhered to them. To characterize adhesion, the use of the index of the exponent describing the distribution of epithelial cells is proposed. With the use of this index, 5 C. albicans strains isolated from candidiasis patients have been found to possess, on the average, higher adhesiveness with respect to epithelial cells than 4 strains isolated from persons without symptoms of candidiasis.     

Antiadhesive effect of the secretion of the oral cavity in the system "Candida albicans--buccal epitheliocytes"

The influence of the oral cavity secretion on adhesive reactions in the system "C. albicans--buccal epitheliocytes" was studied. The treatment of C. albicans with natural saliva led to decrease of adhesive activity. The treatment of C. albicans with antibody absorbed saliva at different temperature conditions led to different changes of adhesion. This effect was determined by the action of temperature-dependent and temperature-independent factors, supposedly of enzymatic nature.     

The study of adhesion of Candida albicans to the selected acrylic resins

The study has been performed on 3 acrylic resins used to fabricate removable dentures. Aim of the study was to detect possible differences in Candida albicans' adhesion within particular materials. Polished and non-polished samples were made, than these samples were sunk in precipitates containing Candida albicans material. Adhesion of Candida albicans to the surface of the materials occured within a concentration of 10. After 24 hours of incubation differences were found concerning the number of the plate cultures. Most of all plate cultures were observed on Lucitone 199, fewer on Zhermacryl, the poorest one was found on Palaxpress resin. Considerable number of plate cultures occured on non-polished samples relating to polished ones. After 48 hours of incubation further development of Candida albicans took place, with differences concerning various materials.