Biomedical subjects
Publications and source records attributed to A Volleková.
Infections caused by Cryptococcus neoformans affect mainly patients with impaired functions of T-cells, and in particular individuals with AIDS. The authors suppose also older subjects in relatively good health to be endangered by this infection. A case of fatal cryptococcal meningoencephalitis with fulminant coarse was detected in a 76-year female patient without evident immunodeficiency.
Bioassay directed fractionation of crude extract from Mahonia aquifolium led to the isolation of fraction A (bisbenzylisoquinoline alkaloid complex, BBI) and a fraction of protoberberine alkaloids, where the major compounds berberine and jatrorrhizine were isolated as their iodides. The antifungal activity of the crude extract, two protoberberine alkaloids and BBI from M. aquifolium stem bark were evaluated against six strains of Malassezia spp. The compounds tested were generally found to possess only weak to moderate antifungal properties: the MICs for individual strains were in the range < or = 50-> or = 1000 mg/L.
Among 162 human isolates of Trichosporon the author isolated according to "crucial" signs (Guého et al. 1992, 1994) the following as dominant: T. mucoides (41%) and T. asahii (33%), T. inkin, T. ovoides and others as well as non-pathogenic T. pullulans were rare in their investigation. To the originally most frequently reported type T. cutaneum belonged less than 10% of the total number of isolates. The variability of physiological and biological signs did not make classification of 5% isolated Trichosporon strains possible. The disc diffusion method confirmed resistance of the tested strains to 5-fluorocytosine, and inhibition by polyene and azole antimycotics.
Three representative Candida albicans strains were selected out of 26 clinical isolates and strains from culture collections on the basis of their high level of conversion to germ tubes and mycelial form at mycelium-promoting culture conditions, and on their different sensitivity to 6-amino-2-n-pentylthiobenzothiazole (APB). When these strains were treated with APB at mycelium-promoting culture conditions, a concentration-dependent decrease in the proportion of germ tubes and hyphae was observed, while the proportion of the yeast from increased. When non-saponifiable lipids were extracted from these cultures and analyzed, a concentration-dependent decrease in ergosterol and an increase in 4-methylated sterols was observed. However, the sensitivity of sterol biosynthesis did not directly relate to the sensitivity of the morphological conversion, and was exhibited at higher concentrations of APB. On the basis of these results it is suggested that the inhibition of germ tube formation and filamentation is not a consequence of inhibition of ergosterol biosynthesis in APB-treated C. albicans.
During the period between September 1994 and August 1996 the authors detected an epidemic of trichophytia superficialis caused by Trichophyton tonsurans among wrestlers (age 10-19 years) of three sports clubs in southwestern Slovakia following their participation in international contests. Underrating of the initial symptoms of the disease, lack of adherence to the ban to engage in contests before complete cure, the relative resistance to topical and systemic treatment etc. led to the development of infection in 52 wrestlers (37% exposed ones). The authors recommend as one of the measures to prevent further import and spread of dermatophytoses measures prohibiting participation of infected sportsmen in any contests at home and abroad.
The authors submit information on a new categorization of microscopic fungi causing human mycoses, as well as criteria of their classification in bio-risk groups (BioSafety Level-BSL) proposed by the European Confederation of Medical Mycology. According to the risk of infection of laboratory workers during handling of cultures isolated from biological specimens almost 400 species of fungi were divided into three groups (BSL 1 and BSL 2-fungi which can produce systemic infections in subjects with immunodeficiencies, or superficial infections in healthy subjects, BSL 3-fungi which can produce severe systemic infections also in healthy subjects). At the same time they express reservations to the classification of some species into groups.
The authors describe an infectious disease, rarely occurring in the Slovak Republic-superficial trichophytia caused by Trichophyton tonsurans var. sulphureum-in a 37-year-old male patient with psoriasis. Untreated oval to circular foci 4-10 x 5-12 cm in size were localised on the forearms and knee, gradually developing black dots remaining after broken hair (parasitismus endothrix). After a failure in local and overall therapy by imidazole antibiotics, the peroral therapy by terbinafine (Lamisil) was successful. (Fig. 2, Ref. 19.)
We have isolated 6 morphologically different axenic yeast cultures from the film surface of red wine. Based on morphological, physiological and biochemical characteristics we have identified the strains as follows: isolates 1-4 are morphologically different strains of the anamorph basidiomycetous film-forming yeast Candida humicola (DASZEWSKA) DIDDENS et LODDER, syn. Apiotrichum humicola (DASZEWSKA) VON ARX WEISMAN. Isolates 5 and 6 belong to the genus Saccharomyces of the associated species S. cerevisiae (isolate 5 originally S. bayanus, isolate 6 S. capensis). These do not participate in the surface film formation.
The authors describe a case of a 31 year old woman who suffered from sclerodermia circumscripta on her right leg. The diagnosis was histopathologically verified. Capillaroscopy and respiratory obstruction were positive. A new lesion appeared on the right arm thus imitating morphea. However, by means of mycological examinations Microsporum gypseum infection was recognized. (Fig. 3, Ref. 13.).