RESUMO
The usefulness of the E-test((R) )has been studied to determine the in vitro susceptibility of 52 isolates of 17 species to five antifungal drugs: amphotericin B, 5-flucytosine, ketoconazole, itraconazole and fluconazole. Minimal inhibitory concentrations were determined following the manufacturers' instructions, except in the preparation of the inoculum. In this case a spectrophotometric method was used to obtain 1-5 ' 10(6) CFU/ml. Two different culture media were included: casitone-agar and RPMI 1640 agar. Most isolates showed clear growth in both media after 96 h of incubation at 37 degrees C. The species showed low MIC concentrations to ketoconazole and itraconazole. Only 55.8% of isolates showed MICs
Assuntos
Antifúngicos/farmacologia , Testes de Sensibilidade Microbiana , Fungos Mitospóricos/efeitos dos fármacos , Ágar , Anfotericina B/farmacologia , Contagem de Colônia Microbiana , Meios de Cultura , Difusão , Farmacorresistência Fúngica , Fluconazol/farmacologia , Flucitosina/farmacologia , Itraconazol/farmacologia , Cetoconazol/farmacologia , Testes de Sensibilidade Microbiana/instrumentaçãoRESUMO
Systemic infections caused by opportunistic fungi have shown an increased frequency in the past 10 years, particularly in immunocompromised patients. Hansenula anomala is an ascosporogenous yeast of the Ascomycetes class found in the skin, throat, and digestive tract transient normal flora. This study was conducted to compare the pathogenicity of H. anomala and Candida albicans in a model of immunocompromised mice. Thirty-eight Swiss mice were divided into two groups as follows: 30 animals received an intraperitoneal (i.p.) injection of cyclophosphamide (200 mg/kg) four days before the induction of infection with H. anomala (1 x 10(6) yeasts/mL), and 8 animals received 100 mg/kg of cyclophosphamide at 3-day intervals during 3 weeks before inoculation of 1 x 10(7) yeasts/mL. All animals were treated with amoxicillin/clavulanic acid (40 mg/kg) four days before induction of infection. A group of mice inoculated with C. albicans (ATCC 64548) served as control. Tissue samples from the lung, spleen, liver, and kidney for histological and mycologic studies were obtained at necropsy. In each animal, the number of viable yeasts per gram of kidney was determined. The organs most frequently infected by H. anomala were the kidneys and the liver (20%), and the lung (10%). However, in conditions of sustained immunosuppression, H. anomala was found in 65.5% of the organs examined. It is concluded that in an experimental model of immunocompromised mice, the pathogenicity of H. anomala was low.
Assuntos
Micoses/microbiologia , Pichia/patogenicidade , Amoxicilina/uso terapêutico , Animais , Contagem de Colônia Microbiana , Ciclofosfamida , Feminino , Humanos , Hospedeiro Imunocomprometido , Imunossupressores , Rim/microbiologia , Fígado/microbiologia , Pulmão/microbiologia , Camundongos , Micoses/tratamento farmacológico , Micoses/imunologia , Neutropenia/induzido quimicamente , Penicilinas/uso terapêutico , VirulênciaRESUMO
The aim of this study was to adapt a spectrophotometric method for preparing the inocula of dematiaceous fungi used for in vitro susceptibility tests. Fifty-two isolates of 17 different species of dematiaceous fungi were used for this purpose. Homogeneous suspensions of conidia and hyphae of these isolates were obtained and adjusted for reading at 530 and 550 nm at 40% and 50% of transmittance. The suspensions were standardised to 1-5 x 10 e6 CFU/ml. Quality controls of the inocula were done by quantitative cultures on agar-Sabouraud plates. The inocula obtained by spectrophotometry showed little variability within all the isolates. This method can be useful for in vitro antifungal evaluation of dematiaceous fungi.
RESUMO
We collected dry blood specimens from two rural areas in Rwanda, that were tested for antibodies to Toxoplasma gondii through the Direct Agglutination technique. 50% of the adults in both communities had antibodies to T. gondii. The Ngenda (NGD) population apparently acquired antibodies at a later stage of its life (only 12% were positive at 14 years of age). The Nyarutovu (NVU) population already showed a 31% positivity at the same age. We would like to point out the pathogenic role played by toxoplasmosis during pregnancy and the need of new studies about the epidemiology of the disease as well as the transmission mechanism in Rwanda.
Assuntos
Toxoplasmose/epidemiologia , Adolescente , Adulto , Fatores Etários , Testes de Aglutinação , Animais , Anticorpos Antiprotozoários/análise , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Saúde da População Rural , Ruanda/epidemiologia , Estudos Soroepidemiológicos , Fatores Sexuais , Fatores Socioeconômicos , Toxoplasma/imunologia , Toxoplasmose/diagnósticoRESUMO
Direct Agglutination (DA) techniques, both, using dry blood samples in filter paper and serum samples, were compared with the ELISA test in order to detect antibodies against Toxoplasma gondii. The results show the validity of the dry blood samples in filter paper for detecting antitoxoplasma antibodies with a DA test. Our results would confirm their usefulness in field epidemiological surveys.