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This review summarizes knowledge on various aspects of paracoccidioidomycosis. Mycelial propagules, chlamydospores, and arthroconidia exhibit thermal dimorphism; arthroconidia are infectious in animals and, by electron microscopy, appear well provided for survival. The mycelial-to-yeast-phase transformation requires a strict control of glucan synthesis(More)
Stability of virulence in P. brasiliensis isolates was studied with respect to the in vitro culture history and methods used for storage. Virulence in yeast-form P. brasiliensis isolates was tested in a chronic pulmonary murine model of paracoccidioidomycosis where progression of disease was quantitated in terms of colony forming units recoverable from(More)
This article provides information on the history of Blastomyces dermatitidis isolates and spontaneous mutants, the relationship with maintenance of cultures, and their virulence as quantified in murine models. Virulent isolates have been obtained from soil or from patients. Regardless of origin, mutants attenuated in virulence have sometimes arisen from(More)
The antifungal activity of voriconazole (VCZ) was tested against Candida albicans in the absence or presence of polymorphonuclear neutrophils (PMN) or monocytes. In some experiments, VCZ was compared to fluconazole (FCZ). On a weight basis, VCZ was 10-fold more efficacious than FCZ against C. albicans Sh27. Against an FCZ-resistant isolate, VCZ at 1(More)
It is well known that some micro-organisms synthesize proteins when stressed by heat or other factors. The function of these proteins is not yet clear, but some of them are believed to be related to resistance against a hostile environment. Histoplasma capsulatum is an intracellular pathogenic fungus that multiplies inside macrophages and resists macrophage(More)
A model of fatal acute pulmonary or chronic pulmonary and disseminated paracoccidioidomycosis was developed by intranasal challenge of young (3-4-week-old) mice with high doses (2.5-10 X 10(7) units) or low doses (0.1-1 X 10(7)) of yeast-phase Paracoccidioides brasiliensis. Fatal acute paracoccidioidomycosis was dose dependent; 10, 5, and 2.5 X 10(7) viable(More)
An animal model of chronic paracoccidioidomycosis was established in male adult BALB/cByJIMR mice by intranasal instillation of different doses of yeast form Paracoccidioides brasiliensis. The inoculum was standardized in terms of virulence, age of the culture, percentage of multicellular fungal units containing 1-3 cells, and viability. Progression and(More)
The viability of Paracoccidioides brasiliensis yeast-form cells was determined by colony-forming units, direct fluorescent staining, and production of germ tubes in slide culture. The first procedure was unreliable and time consuming; the latter two showed better correlation with hemacytometer total cell counts and required significantly less time.
The fungicidal capacity of murine pulmonary macrophages (PuM) activated in vitro with IFN or lymphokines or in vivo with IFN was studied. PuM treated overnight with IFN (1000 U/ml), Con A-stimulated spleen cell culture supernatants, or lymph node cells plus Con A significantly killed yeast cells of the Gar w isolate of Paracoccidioides brasiliensis 45.5 +/-(More)
The inhibitory effect of human serum on the multiplication of Cryptococcus neoformans and the interaction with fluconazole were studied. Compared with cryptococcal multiplication in RPMI 1640 medium alone, 5% human serum in medium inhibited multiplication by 76% +/- 6% (n = 8). The inhibitory effect of human serum was donor independent, [corrected] heat(More)