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Aim: To evaluate the inhibition of efflux pumps by using promethazine (PMZ) as a strategy to control Fusarium solani species complex (FSSC). Materials & methods: The susceptibility of FSSC strains to PMZ and the interaction between PMZ and antifungals were evaluated. The efflux pump activity was confirmed by flow cytometry with rhodamine 6G. Finally, PMZ was tested against FSSC biofilms. Results: PMZ inhibited FSSC planktonic growth and showed synergism with antifungals. PMZ reduced R6G efflux and inhibited cell adhesion, impaired the development of biofilms and disrupted mature biofilms. PMZ-challenged biofilms showed increased sensitivity to amphotericin B. Conclusion: The study provides indirect evidence of the occurrence of efflux pumps in FSSC and opens a perspective for this target in the control of fusariosis.

Serologic diagnosis has been presented as a safe alternative for coccidioidomycosis. However, commercial kits based on coccidioidal antibodies available in the USA are considered too expensive for laboratories outside that country. In this study, we describe the preparation of antigens for detection of human coccidioidal antibodies by the immunodiffusion test (ID) and enzyme immunoassay (EIA). Antigens were tested against serum samples from patients with coccidioidomycosis, histoplasmosis and paracoccidioidomycosis, as well as healthy individuals. The highest reactivity in the ID tests was seen in the F0-90 antigen. In the EIAs, the best results were obtained with the F60-90 antigen. None of the serum samples from healthy individuals were recognized by any of the antigen extracts tested by ID or EIA. In conclusion, the F0-90 and F60-90 antigens have the potential to be commercially employed in presumptive diagnosis of coccidioidomycosis by ID or EIA, respectively. The tests could improve serological diagnosis of coccidioidomycosis in South America.

The aim of the present study was to evaluate the effect of cotrimoxazole on the in vitro susceptibility of Coccidioides posadasii strains to antifungals. A total of 18 strains of C. posadasii isolated in Brazil were evaluated in this study. The assays were performed in accordance with the Clinical and Laboratory Standards Institute guidelines and the combinations were tested using the checkerboard method. The minimum inhibitory concentrations were reduced by 11, 2.4, 4.3 and 3.5 times for amphotericin B, itraconazole, fluconazole and voriconazole, respectively. Moreover, it was seen that cotrimoxazole itself inhibited C. posadasii strains in vitro. The impairment of folic acid synthesis may be a potential antifungal target for C. posadasii.

Cockatiels are the world's second most popular psittacine pet bird, but no data characterizing their gastrointestinal microbiota have been found. Thus, the aim of this work was to characterize the yeast gastrointestinal microbiota of cockatiels and to evaluate the relevance of cockatiels as carriers of potentially pathogenic yeasts. A total of 60 cockatiels, from 15 different premises, were assessed. A thorough clinical examination was performed with each bird, and samples were collected from oral cavity, crop and cloaca. The stools were collected from cages where the birds were kept. The isolates were identified according to morphological and biochemical characteristics. Yeasts were isolated from at least one anatomical site of 65% of the birds and 64.3% of the stool samples. The oral cavity (53.3%) and the crop (58.3%) were the anatomical sites with the highest prevalence and the highest number of yeast isolates. Overall, 120 yeast isolates, belonging to 13 species, were obtained. The most frequently isolated species were Candida albicans, with 39 (32.5%) isolates, followed by Candida tropicalis (20%), Trichosporon asteroides (12.5%), Candida famata (10%) and others. Mixed yeast colonies were isolated from 23.3% of the birds and C. albicans was seldom found in association with other species (P<0.05). The results of this work demonstrated that cockatiels harbour potentially pathogenic yeasts throughout their gastrointestinal tract and in stools, and are prone to disseminating them in the environment.

The aim of the present study was to evaluate the in vitro interactions of antituberculous drugs (ATDs) with antifungals against Coccidioides posadasii. Eighteen drug combinations, formed by an ATD (isoniazid, pyrazinamide or ethambutol) plus an antifungal (amphotericin B, ketoconazole, itraconazole, fluconazole, voriconazole or caspofungin), were tested using the checkerboard method. All the antimicrobial combinations inhibited C. posadasii strains and synergistic interactions were observed for 10 combinations. Antagonism between the tested drugs was not observed. Stronger synergistic interactions were seen in the combinations formed by triazoles plus ethambutol as well as itraconazole plus pyrazinamide. Further studies in animal models are needed to confirm the usefulness of these combinations.

The aim of this study was to perform a retrospective analysis of cases of candidemia in a Brazilian hospital in the city of Fortaleza, Ceará. A total of 50 blood cultures were analyzed from 40 candidemic patients. The mycological diagnosis was based on the phenotypical analysis and the patients' data were recorded in appropriate files. The most frequent species were Candida parapsilosis (n = 18), followed by C. albicans (n = 14), C. tropicalis (n = 8), C. guillermondii (n = 6), C. glabrata (n = 2), and Candida spp. (n = 2). A detailed descriptive study was undertaken with 21 patients whose medical records were complete. The candidemia episodes occurred in eight male patients and 13 female patients. The most representative risk factors implicated in candidemia were prior antibiotic therapy, central venous catheters, parenteral nutrition, gastric probes and mechanical ventilation. Death occurred in 13 of the 21-candidemic patients. This study demonstrated the emergence of candidemia caused by C. parapsilosis in a Brazilian hospital in the city of Fortaleza, Ceará.

Dermatophytes are a group of fungi that are capable of invading keratinized tissues of humans and other animals. Antifungal susceptibility analysis and genetic studies by random amplification of polymorphic DNA (RAPD), have been used to detect polymorphism as well as determining the possible resistance of dermatophytes to antifungals. The aim of this study was to evaluate the possible correlation between the antifungal susceptibility and genotypical pattern of Microsporum canis strains isolated in dogs and cats with dermatophytosis in Northeast Brazil. The antifungal susceptibility study was conducted using the broth microdilution test with griseofulvine, ketoconazole, itraconazole, and fluconazole. The genotypical analysis was performed using the RAPD method. The antifungal susceptibility analysis showed that all the strains of M. canis analyzed (n = 22) were sensitive to griseofulvine (0.25 microg/mL < or minimum inhibitory concentration (MIC) < or = 1 microg/mL), ketoconazole (0.25 microg/mL < or = MIC < or = 2 microg/mL), itraconazole (0.25 microg/mL < or = MIC < or = 1 microg/mL), and fluconazole (1 microg/mL < or = MIC < or = 16 microg/mL). The RAPD results showed that all analyzed strains are genetically similar. Thus, based on antifungal susceptibility analysis and RAPD data, a possible correlation can be shown between the antifungal susceptibility and the genotypical pattern of the strains of M. canis from Northeast Brazil.

Knowledge of epidemiological and mycological characteristics of onychomycosis has been noted by many authors as being an important tool for control of these fungal infections. This study seeks to improve knowledge of onychomycosis epidemiology and mycological features. Samples were taken from infected fingernails and toenails of 976 patients undergoing treatment at a respected Dermatology Center in Ceará, Fortaleza, CE, Brazil. Specimens from 512 patients (52%) were positive for onychomycosis. From the culture-positive samples, yeasts of the genus Candida (C. albicans, C. tropicalis, C. krusei, C. parapsilosis) were dominant. The dermatophytes isolated (Trichophyton rubrum, T. tonsurans, T. mentagrophytes var. mentagrophytes) were dominant in 46 patients (12.99%). The mould Fusarium spp. was isolated from 29 patients (8.19%). Yeast of the genus Candida is the main causal factor in onychomycosis in our region. Also, the study showed the importance of performing direct examination and culture in diagnosis of onychomycosis.