RESUMEN
An increased catalase activity in Candida spp. has been suggested as a mechanism that reduces amphotericin B activity. Furthermore, resistance to antifungal agents like amphotericin B has been reported in some cancer patients undergoing chemotherapy treatment. In this study we analysed the influence of chemotherapy agents on catalase activity in Candida albicans, the major species involved in yeast infections. Eight strains of C. albicans isolated from HIV-positive patients were exposed to cyclophosphamide, cytarabine, dacarbazine and methotrexate antineoplastic drugs at the concentrations used during therapy. Catalase activity was measured and compared to the control group. Very significant differences (P < 0.01) were found when C. albicans was exposed to methotrexate (2 microg ml(-1) = 4 microM). For cyclophosphamide (50 microg ml(-1)), cytarabine (1 microg ml(-1)) and dacarbazine (8 microg ml(-1)), no differences were found (P > 0.05) between the control and drug-exposed groups. Although more extensive studies are necessary, these data do suggest that the antineoplastic drug methotrexate contributes to the resistance to antifungal drug therapy by varying catalase activity.
Asunto(s)
Antimetabolitos Antineoplásicos/farmacología , Candida albicans/efectos de los fármacos , Candida albicans/enzimología , Catalasa/metabolismo , Humanos , Cinética , Metotrexato/farmacologíaRESUMEN
O ultra- som terapêutico é um aparelho de eletroterapia largamente utilizado como recurso fisioterapêutico no tratamento de diversas patologias do sistema músculo-esquelético. Em virtude disso, elaborou-se um questionário para verificar o emprego deste aparelho em diversas clínicas de fisioterapia de Santa Maria - RS. O questionário, aplicado a 14 clínicas de fisioterapia, constava de ítens como frequência mais utilizada, dosimetria empregada, agentes de acoplamento utilizados, calibragem, incidência anual de danos nos aparelhos e aparelhos submetidos à assistência técnica especializada. Os resultados obtidos foram analisados descritivamente e säo apresentados, neste artigo, sob a forma de figuras.