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The ultrastructural changes produced by ketoconazole on the yeast-phase of H. capsulatum and P. brasiliensis were studied by means of scanning and transmission electron microscopy. The observed alterations on both fungi were very similar to those induced by the same drug on the ultrastructure of C. albicans. These alterations include surface changes, abnormal membrane proliferation, fatty degeneration of the cytoplasm and lysis of subcellular organelles. P. brasiliensis seems to be more sensitive to ketoconazole than H. capsulatum, since the necrosis of most of the cells was obtained in the former at a concentration of 0.1 gmg/ml and in the latter at 1 μg/ml. [ABSTRACT FROM AUTHOR]

The ultrastructural changes produced by ketoconazole in the yeast-phase of H. capsulatum and P. brasiliensis were studied by means of scanning and transmission electron microscopy. The observed alterations on both fungi were very similar to those induced by the same drug on the ultrastructure of C. albicans. These alterations include surface changes, abnormal membrane proliferation, fatty degeneration of the cytoplasm and lysis of the subcellular organelles. P. brasiliensis seems to be more sensitive to ketoconazole than H. capsulatum, since the necrosis of most of the cells was obtained in the former at a concentration of 0.1 microgram/ml and in the latter at 1 microgram/ml.

Some of the biological properties of saline extracts of the mycelia of several species of the Aspergillus genus, namely, A. fumigatus, A. flavus, A. niger, A. nidulans, A. parasitucus and A. glaucus, were studied. Only the extract prepared from A. fumigatus was found to be hemolytic for sheep red blood cells. In contrast, all the extracts with the only exception of that of A. glaucus, had cytotoxic effects on Vero cells. Both, the hemolytic and cytotoxic constituents of the extracts were removable by adsorption with activated carbon. Heating of the extracts at 100 degrees C for 30 minutes also resulted in detoxification. In vivo studies, performed only with detoxified extracts of A. fumigatus, showed these were capable of depleting complement levels in guinea pigs. Complement inactivation was also found to occur in vitro and was cuased by all the extracts tested. Also triggered by the extracts was the conversion of serum C3 but not of purified C3, indicating that other serum factors are essential in the process. Despite the similarity in this respect with cobra venom factor, differences in activity after heating-negative in cobra venom factor-indicate that the complement inactivating substance/s present in the Aspergillus extracts differ from those of the snake product.