140 resultados para Paracoccidioides braciliensis
Resumo:
Chemical investigation of Hyptidendron canum stems resulted in the isolation of betulinic, ursolic and euscaphic acids. From the leaves were isolated 3β-O-β-galactopiranosilsitosterol, ursolic aldehyde, and mixtures of maslinic acid and 2α-hydroxyursolic acid, α and β-amyrin, uvaol and erythrodiol, sitosterol and stigmasterol, spathulenol and globulol. Hexane and chloroform leave fractions as well as ursolic and betulinic acids showed antifungal activities against the yeast form of Paracoccidioides brasiliensis.
Resumo:
A paracoccidioidomicose é uma importante micose sistêmica, endêmica na América Latina. A infecção é usualmente adquirida por inalação das partículas do micélio. Na sua maioria são infecções assintomáticas e estão associadas a vários fatores do hospedeiro, como sexo, idade, fatores genéticos, bem como às características do agente infeccioso e sua virulência. Apresentamos um caso de mastite por paracoccidioidomicose, com o objetivo de demonstrar que pacientes idosas e com abcessos na mama devem ser submetidas à biópsia.
Resumo:
Pulmonary dysfunction represents the most important cause of death in patients with paracoccidioidomycosis (PBM). In order to investigate the functional changes of the lungs in the early stages of PBM, a model of benign disease was developed by intratracheal challenge of 12-week old isogenic Wistar rats with 1 x 106 yeast forms of Paracoccidioides brasiliensis. Animals were studied 30 and 60 days after infection, when fully developed granulomas were demonstrable in the lungs. Measurements of airway resistance, lung elastance and tissue hysteresis were made during sinusoidal deformations (100 breaths/min, tidal volume = 2 ml) with direct measurement of alveolar pressure using the alveolar capsule technique. Infection caused a significant increase in hysteresis (infected: 1.69, N = 13; control: 1.13, N = 12, P = 0.024, ANOVA), with no alterations in airway resistance or lung elastance. Histopathological analysis revealed the presence of fully developed granulomas located in the axial compartment of the lung interstitial space. These results suggest that alterations of tissue mechanics represent an early event in experimental PBM
Resumo:
Different patterns of granulomas have been observed in 6- to 8-week-old mice after ip inoculation with 5 x 10(6) yeast cells of Paracoccidioides brasiliensis. Transforming growth factor-ß (TGF-ß) is a cytokine that has been shown to participate in fibrosis and granuloma formation; its activities seem to be modulated by the small proteoglycan decorin. In the present study, TGF-ß and decorin expression in epiploon granulomas was assessed by immunohistochemistry in susceptible (B10.A) and resistant (A/J) mice after 15, 30, 120 and 150 days of P. brasiliensis ip infection. The epiploon was collected, fixed in Methacarn solution and embedded in paraffin, and 5-µm thick sections were used for immunohistochemical analysis employing the streptavidin-biotin-peroxidase technique. The former mouse strain developed fatal disease with many disseminated lesions increasing in size and number during the infection and the latter developed mild disease with the presence of encapsulated granulomas. In the epiploon, TGF-ß was present on macrophages, giant cells, lymphocytes and fibroblasts, and absent on neutrophils. It was also detected in areas of fibrosis and necrosis, as well as disperse in amorphous extracellular matrix, mostly in resistant mice. Decorin was present circumscribing macrophages and giant cells containing fungi, but absent on these cells. In both mouse strains, decorin was found at the periphery of the lesions, and markedly in milky spot granulomas. In resistant mice, positivity was found around fibrotic and necrotic areas of encapsulated and residual lesions containing lysed fungi. Decorin was found associated with thick fibers around encapsulated lesions. In susceptible mice, the size and number of lesions increased with the progression of the disease and were correlated with the weaker expression of decorin. We suggest an association of decorin with the fibrogenic process observed in paracoccidioidal granulomas.
Resumo:
Paracoccidioidomycosis (PCM) is a chronic systemic mycosis caused by the inhalation of the thermally dimorphic fungus Paracoccidioides brasiliensis as well as the recently described P. lutzii. Because the primary infection occurs in the lungs, we investigated the differential involvement of the right and left lungs in experimental P. brasiliensis infection. Lungs were collected from C57BL/6 mice at 70 days after intravenous infection with 1×106 yeast cells of a virulent strain of P. brasiliensis (Pb18). The left lung, which in mice is smaller and has fewer lobes than the right lung, yielded increased fungal recovery associated with a predominant interleukin-4 response and diminished synthesis of interferon-γ and nitric oxide compared with the right lung. Our data indicate differential involvement of the right and left lungs during experimental PCM. This knowledge emphasizes the need for an accurate, standardized protocol for tissue collection during studies of experimental P. brasiliensis infection, since experiments using the same lungs favor the collection of comparable data among different mice.