ABSTRACT
This study evaluated the in vitro interaction between ciprofloxacin (CIP) and classical antifungals against Histoplasma capsulatum var. capsulatum in mycelial (n = 16) and yeast-like forms (n = 9) and Coccidioides posadasii in mycelial form (n = 16). This research was conducted through broth microdilution and macrodilution, according to Clinical Laboratory Standards Institute. Inocula were prepared to obtain from 0.5 × 10(3) to 2.5 × 10(4) cfu ml(-1) for H. capsulatum and from 10(3) to 5 × 10(3) cfu ml(-1) for C. posadasii. Initially, minimum inhibitory concentration (MIC) for each drug alone was determined. Then, these MICs were used as the highest concentration for each drug during combination assays. The procedures were performed in duplicate. For all combination assays, MICs were defined as the lowest concentration capable of inhibiting 80% of visible fungal growth, when compared to the drug-free control. Drug interaction was evaluated by paired sample t-Student test. The obtained data showed a significant MIC reduction for most tested combinations of CIP with antifungals, except for that of CIP and voriconazole against yeast-like H. capsulatum. This study brings potential alternatives for the treatment of histoplasmosis and coccidioidomycosis, raising the possibility of using CIP as an adjuvant antifungal therapy, providing perspectives to delineate in vivo studies.
Subject(s)
Antifungal Agents/pharmacology , Ciprofloxacin/pharmacology , Coccidioides/drug effects , Histoplasma/drug effects , Caspofungin , Coccidioides/growth & development , Drug Evaluation, Preclinical , Drug Synergism , Echinocandins/pharmacology , Histoplasma/growth & development , Lipopeptides , Microbial Sensitivity Tests , Mycelium/drug effects , Pyrimidines/pharmacology , Triazoles/pharmacology , VoriconazoleABSTRACT
The effects of the protease inhibitors saquinavir, darunavir, ritonavir, and indinavir on growth inhibition, protease and phospholipase activities, as well as capsule thickness of Cryptococcus neoformans were investigated. Viral protease inhibitors did not reduce fungal growth when tested in concentrations ranging from 0.001 to 1.000 mg/L. A tendency toward increasing phospholipase activity was observed with the highest tested drug concentration in a strain-specific pattern. However, these drugs reduced protease activity as well as capsule production. Our results confirm a previous finding that antiretroviral drugs affect the production of important virulence factors of C. neoformans.
Subject(s)
Anti-Retroviral Agents/pharmacology , Cryptococcus neoformans/drug effects , Gene Expression Regulation, Fungal/drug effects , Protease Inhibitors/pharmacology , Cryptococcus neoformans/enzymology , Cryptococcus neoformans/pathogenicity , Indinavir/pharmacology , Ritonavir/pharmacology , Saquinavir/pharmacology , Virulence Factors/geneticsABSTRACT
Candida meningitis is a rare condition that occurs more frequently in premature infants, immunocompromised patients or patients after neurosurgery. We describe a case of a previously healthy 41-year-old man with Candida parapsilosis meningitis associated with oropharyngeal candidiasis as the first manifestation of AIDS.
Subject(s)
Acquired Immunodeficiency Syndrome/complications , Acquired Immunodeficiency Syndrome/diagnosis , Candida/isolation & purification , Candidiasis, Invasive/diagnosis , Candidiasis, Invasive/pathology , Meningitis, Fungal/diagnosis , Meningitis, Fungal/pathology , Adult , Candida/classification , Candidiasis, Oral/diagnosis , Candidiasis, Oral/pathology , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Electrophoresis, Agar Gel , Humans , Male , Polymerase Chain ReactionABSTRACT
As curvas de calibração de sódio e de potássio feitas para estudo das dosagens desses íons pela fotometria de chama mostraram serem lineares quando se trabalha com fotômetro de chama de padrão interno. No entanto, nos experimentos feitos no fotômetro de leitura direta, os resultados do sódio não mostraram linearidade. Estudos da função e do ajuste dessa curva leva à proposição de uma fórmula (x = exp{(ln y- 4,369/0,724)}) para se corrigir os processos de interpolação e extrapolação das leituras fotométricas para se obter a concentração do sódio dosado por esse tipo de aparelho. Discute-se, nesse trabalho, as causas dessa não linearidade e a utilização dessa fórmula nos cálculos laboratoriais.
