Cryptococcal infection had an increased incidence in last yearsCryptococcal infections have increased dramatically over the last years. This high incidence can be due in large part to the explosion of acquired immune deficiency syndrome (AIDS) epidemic around the world and the use of more potent immunosuppressive agents by increasing numbers of solid organ transplant recipients (Mitchell & Perfect 1995, Dromer et al. 1996.Cryptococcal meningitis, the most common infection of cryptococcosis is usually chronic and uniformly fatal if untreated (Collazos 2003). Some antifungal drugs, such as polyene macrolides (amphotericin B) and azoles (itraconazole and fluconazole) are currently used in antifungal therapies with certain limitations due to side effects as toxicity and emergence of resistant strains (Terrel 1999, Saag et al. 2000. The lack of response to treatment and resistance in vitro to fluconazole, the drug that now commands maintenance treatment protocols for AIDS patients has began to emerge with Cryptococcus neoformans var. neoformans in immunocompromissed patients undergoing prolonged azole treatment (Alves et al. 1997, Momoff & Parrish 2003 The medicinal plants have been used for several purposes including antimicrobial effects and have showed inhibition of growth to fungi. Caryocar brasiliensis, plant widely distributed in Brazil, has in vitro activity against Paracoccidioides brasiliensis and C. neoformans while Hyptis ovalifolia, plant native from Brazilian cerrado, has inhibitory effect on dermatophytes (Souza et al. 2002). We are interested on antifungal activity of Ocimum gratissimum, plant known as alfavaca cravo, which has presented in vitro inhibitory effect against bacteria as Staphylococcus aureus, Escherichia coli, and some fungi as dermatophytes (Lima et al. 1993, Nakamura et al. 1999.The occurrence of cryptococcosis in Goiânia and its importance in immunocom-promised patients justify in studying Cryptococcus species in this city localized in the Brazilian midwest region. In this paper the antifungal activity of ethanolic crude extract, ethyl acetate, hexane and chloroformic fractions, essential oils and eugenol from O. gratissimum leaves towards 25 isolates of C. neoformans, important pathogen commonly found in our geographic area , was investigated. Chemical analysis of essential oil -Oil sample analysis was performed on a Shimadzu QP5050A gas chromatograph interfaced to a mass spectrometer (GC/MS) instrument employing the following conditions: fused silica capillary column (CBP-5; 30 m x 0.25 µm x 0.25 µm) which was programmed as follows: 60ºC for 2 min and then up to 240ºC at 3ºC/min, then to 270ºC at 10ºC/min ending with a 10 min at 270ºC. The carrier gas was He at a flow rate of 1 ml/min, split mode, with ratio of 1:5, and injection volume of 1 µl in CH 2 Cl 2 and the ionization voltage, 70 EV. The calculation of the retention indexes was made through co-injection with C 8 -C 32 n alkanes series (Van Den Doll & Kratz 1963). Identification of the oil constituents was made based on the ...

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Some antifungal agents have shown to exert effects on expression of virulent factors of Candida as the production of secretory aspartyl proteinase (Sap). In this study, we sought to determine and to compare the influence of fluconazole and voriconazole in proteinase activity of this microorganism. Thirty-one isolates obtained from oral mucosa of human immunodeficiency virus positive (HIV) patients were used in this study. The minimal inhibitory concentrations (MIC) of fluconazole and voriconazole were determined using the broth microdilution method with RPMI 1640 medium and with yeast carbon base-bovine serum albumin (YCB-BSA) medium. The Sap activity following by digestion of BSA as substrate was determined for four Candida albicans strains arbitrarily chosen according to susceptibility (susceptible or resistant) to fluconazole or voriconazole. Besides, the SAP1 to SAP7 genes were screened by PCR for the same isolates that were determined by the Sap activity. In vitro susceptibility testing using the two media presented similar MIC values. Increased Sap activity was observed in resistant isolates on presence of drugs, but the Sap activity by susceptible isolates to azoles showed different behavior on the presence of drug. We detected the presence of SAP1 to SAP7 genes from all susceptible or resistant C. albicans isolates. The present study provides important data about the proteinase activity and the presence of genes of SAP family in fluconazole and voriconazole susceptible or resistant C. albicans isolates.

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A clear understanding of the pharmacodynamic properties of antifungal agents is important for the adequate treatment of fungal infections like candidiasis. For certain antifungal agents, the determination of Minimal Fungicidal Concentration (MFC) and time kill curve could be clinically more relevant than the determination of the Minimal Inhibitory Concentration (MIC). In this study, MIC and MFC to fluconazole, amphotericin B and caspofungin against C. albicans isolates and the killing patterns obtained with caspofungin and amphotericin B against susceptible and resistant strains to fluconazole were determined. The results of MICs showed that all C. albicans isolates were highly susceptible to amphotericin B, but two isolates were fluconazole resistant. The comparative analysis between MIC and MFC showed that MFC of fluconazole was fourfold higher than MIC in 41.9% of the C. albicans isolates. Same values of MFC and MIC of amphotericin B and caspofungin were found for 71% of the isolates. Correlation between time kill curves and MFC of amphotericin B and caspofungin against all 4 isolates tested was observed. The caspofungin killing effect was more evident at MFC in 6 hours of incubation than at MIC in this time, suggesting dependence of concentration. The similarity of results of time-kill curve and MFC values indicate that determination of MFC is an alternative for the detection of the fungicidal activity of these drugs.

The purpose of this study was to compare the agar dilution and broth microdilution methods for determining the minimum inhibitory concentration (MIC) of fluconazole, itraconazole, ketoconazole, griseofulvin and terbinafine for 60 dermatophyte samples belonging to the species Trichophyton rubrum, Trichophyton mentagrophytes and Microsporum canis. The percentage agreement between the two methods, for all the isolates with < 2 dilutions that were tested was 91.6% for ketoconazole and griseofulvin, 88.3% for itraconazole, 81.6% for terbinafine and 73.3% for fluconazole. One hundred percent agreement was obtained for Trichophyton mentagrophytes isolates evaluated with ketoconazole and griseofulvin. Thus, until a reference method for testing the in vitro susceptibility of dermatophytes is standardized, the similarity of the results between the two methods means that the agar dilution method may be useful for susceptibility testing on these filamentous fungi. Key-words:In vitro susceptibility. Agar dilution. Broth microdilution. Dermatophytes. RESUMOO propósito do presente trabalho foi comparar os métodos de diluição em ágar e diluição em caldo para a determinação de concentração inibitória mínima de fluconazol, itraconazol, cetoconazol, griseofulvina e terbinafina para 60 amostras de dermatófitos pertencentes às espécies, Trichophyton rubrum, Trichophyton. mentagrophytes e Microsporum canis. A porcentagem de acordo entre os dois métodos para todos os isolados testados considerando-se valores < 2 diluições, foram de 91,6% para cetoconazol e para griseofulvina, de 88,3% para itraconazol, de 81,6% para terbinafina e de 73,3% para fluconazol. Uma concordância de 100% foi obtido para isolados de Trichophyton mentagrophytes avaliados com cetoconazol e griseofulvina. Desta forma, até que um método de referência seja padronizado para testar a suscetibilidade in vitro para os dermatófitos, os resultados semelhantes encontrados para os dois métodos fazem com que o método de diluição em ágar possa ser útil no teste de suscetibilidade para estes fungos filamentosos. Palavras-chaves:Suscetibilidade in vitro. Diluição em ágar. Microdiluição em caldo. Dermatófitos.

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