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.     

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.     

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.     

Bacterial-fungal associations in the intestine under the conditions of colonization by yeast-like fungi of the genus Candida

The composition of the fecal microflora in somatic patients and patients with enteric infections under the conditions of surpluscolonization by yeast-like fungi of the genus Candida was analyzed. The study revealed that the high level of fungal contamination was linked with decreased colonization resistance of the intestine (deficiency in bifidoflora) and with the presence of opportunistic microorganisms: Staphylococcus aureus, hemolytic and lactose-negative Escherichia coli, as well as nonfermenting Gram negative bacteria. The antilysozyme activity of enterobacteria was found to increase in the course of their joint cultivation with fungi of the genus Candida, that may be regarded as one of the mechanisms of the formation and maintenance of pathobiocenosis.     

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.     

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.     

The genus Candida Berkhout

The properties of 53 fermentation type II strains of the genusCandida Berkhout were studied. The strains in question were originally identified asCandida tropicalis (Castellani) Berkhout,Candida pelliculosa Redaelli,Candida robusta Diddens et Lodder,Candida intermedia (Cif. et Ashf.) Langeron et Guerra,Candida langeroni Dietrichson,Candida obtusa (Dietrichson) v. Uden et Carmo Sousa and as various intermediate forms between these and other similar species. The classification criteria were extended by a number of very important characteristics, such as the degree of utilization of raffinose, the assimilation of lysine, xylose, cellobiose, maltotriose, maltotetraose and arabinose, virulence for mice, nutrient requirements, serological properties, etc. Actual classification was based on the numerical method of a similarity count. On the basis of this extension of the classification criteria, the characteristics of the speciesCandida tropicalis (Castellani) Berkhout andCandida pelliculosa Redaelli were defined in greater detail.Candida intermedia, evaluated on the basis of previously employed characteristics (lactose utilization, non-assimilation of KNO₃) does not appear to be a separate species, but a collection of different border-line forms of other species of this group.Candida robusta Diddens et Lodder is regarded as a member of the genusSaccharomyces, notCandida. The varietiesCandida tropicalis var.lambica andCandida pelliculosa var.cylindrica likewise do not seem to belong to the species concerned and will have to be studied in greater detail from the genetic aspect, in relation to other membrane-forming types ofCandida. The authors' extension of the classification criteria considerably reduced intraspecific variability, particularly in the speciesCandida tropicalis (Castellani) Berkhout, and led to greater accuracy in the practical diagnosis of this species, which is frequent in clinical material.     

The characteristics of the ultrastructural changes in yeast-like fungi of the genus Candida exposed to therapeutic-range ultrasound and nystatin]

The electron microscopic study of the ultrastructure of yeast-like fungi of the genus Candida under the action of nystatin and sonication, as well as the action of these two factors used in combination, was carried out. In this study the degree of preservation of the structure of fungal cells was evaluated and the percentage of cells with different ultrastructural changes was determined. Observations made 3 and 24 hours after sonication and treatment with nystatin, used in combination, showed that ultrastructural changes in fungal cells were more pronounced than in the cells subjected to the action of nystatin alone. 24 hours after the combined physico-medicinal treatment of Candida the percentage of nonviable blastospores among them was 5-fold higher than that of such cells among Candida subjected to treatment with nystatin alone and more than 20-fold higher than among Candida subjected only to sonication. These data on the increased fungicidal effect of nystatin used in combination with sonication substantiate the expediency of the above-mentioned physico-medicinal treatment in cases of candidal lesions of the skin and its appendages, which is one of the ways for increasing the effectiveness of the treatment of this mycosis.     

Experimental study of the effect of corticosteroid preparations on the adhesion of Candida genus fungi to the epitheliocytes of mucous membranes

The effect of corticosteroids on the adherence of Candida cells to epithelial cells was studied with the use of the original modification of the in vitro adherence assay. The administration of hydrocortisone acetate to mice resulted in the increased adherence of the pathogenic fungi to epithelial cells: after 10-day hormone treatment the adherence number and the adherence index increased, respectively, to 230% and 360% of control values. After 20-day treatment these characteristics increased, respectively, to 260% and 700%. The adherence of C. albicans to vaginal epithelial cells in female mice receiving corticosteroids increased in comparison with that in the control animals at estrus: the adherence number increased to 220% and the adherence index, to 470% of the level observed in the controls.     

Simple new test for presumptive differentiation between genus Candida and genus Prototheca

A differential test was made between genus Candida and genus Prototheca using a new and very simple differential test.A total of 59 strains of Candida and 78 strains of Prototheca were used. The basis of the test was the differential use of a disc carrying 60 mcg of Rybostamicin to which all the Candida were resistant and the Prototheca inhibited.