In vitro activities of caspofungin, amphotericin B and azoles against Coccidioides posadasii strains from Northeast, Brazil

Coccidioidomycosis is a systemic infection caused by the soil-dwelling dimorphic fungi Coccidioides spp. the disease is endemic in semiarid Northeast Brazil, where it is caused by C. posadasii. the aim of this study was to perform antifungal susceptibility tests of clinical and environmental strains of C. posadasii from Northeast Brazil. the in vitro activities of caspofungin, amphotericin B and azoles against clinical and environment isolates of C. posadasii were determined in accordance with the NCLLS M-38P macrodilution method. the antifungal susceptibility analysis showed that all the strains of C. posadasii (n = 10) were sensitive to caspofungin (16 mu g/ml <= MIC <= 32 mu g/ml), amphotericin B (0.0625 mu g/ml <= MIC <= 0.125 mu g/ml), ketoconazole (0.039 mu g/ml <= MIC <= 0.156 mu g/ml), itraconazole (0.125 mu g/ml <= MIC <= 0.5 mu g/ml), fluconazole (3.125 mu g/ml <= MIC <= 6.25 mu g/ml), and voriconazole (0.125 mu g/ml). This study is the first description of in vitro antifungal susceptibility pattern of Brazilian strains of C. posadasii.Univ Fed Ceara, Med Mycol Specialized Ctr, Fortaleza, Ceara, BrazilUniv Fed Ceara, Postgrad Program Med Sci, Fortaleza, Ceara, BrazilUniv Estadual Ceara, Dept Biol Sci, Fortaleza, Ceara, BrazilUniv Estadual Ceara, Postgrad Program Vet Sci, Fortaleza, Ceara, BrazilUniv Fed Ceara, Postgrad Program Med Clin, Fortaleza, Ceara, BrazilUniv Fed Ceara, Dept Biol Sci, Fortaleza, Ceara, BrazilUniversidade Federal de São Paulo, Dept Microbiol Immunol & Parasitol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Microbiol Immunol & Parasitol, São Paulo, BrazilWeb of Scienc

Antifungal and marker effects of Talisia esculenta lectin on Microsporum canis in vitro

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Aims: The purpose of this study was to demonstrate the usefulness of lectin obtained from Talisia esculenta (TEL) seeds as a tool to recognize and study Microsporum canis. For this purpose, we investigated the antifungal and marker action of this lectin and the relationship of these effects with the presence of carbohydrates on the structure of this fungus. Methods and Results: The in vitro antifungal activity of TEL was analysed by broth microdilution assay. In addition, TEL was assessed against the arthroconidia present on hairs obtained from infected dogs and cats. The affinity of fluorescein isothiocyanate (FITC)-labelled TEL for macroconidia and arthroconidia of M. canis was also tested. The effects of TEL on the growth of the M. canis strains began with 0 center dot 125 mg ml-1, and 100% inhibition was obtained with a concentration of 2 mg ml-1. The addition of carbohydrates, especially N-acetyl-glucosamine and d-mannose, inhibited these antifungal effects. TEL was able to inhibit the growth of arthroconidial chitin-rich forms of M. canis obtained from hairs of infected animals and strains cultured in Sabouraud agar. FITC-labelled TEL efficiently marked macroconidial and arthroconidial forms of M. canis, as shown by fluorescent microscopy. Conclusions: These results show that the inhibitory effects of TEL on M. canis growth may be related to the interaction of lectin with the carbohydrates present at the micro-organism's surface, mainly d-mannose and N-acetyl-glucosamine. Significance and Impact of the Study: Talisia esculenta can be used as an important tool in the biochemical study of M. canis or as a molecule to recognize this dermatophyte in infected tissue.107620632069Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)FUNCAP (Ceara State Research Support Foundation) [9836/06]Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)CNPq [475724/2006-2]FUNCAP (Ceara State Research Support Foundation) [9836/06

The global epidemiology of emerging Histoplasma species in recent years

Histoplasmosis is a serious infectious disease in humans caused by Histoplasma spp. (Onygenales), whose natural reservoirs are thought to be soil enriched with bird and bat guano. The true global burden of histoplasmosis is underestimated and frequently the pulmonary manifestations are misdiagnosed as tuberculosis. Molecular data on epidemiology of Histoplasma are still scarce, even though there is increasing recognition of histoplasmosis in recent years in areas distant from the traditional endemic regions in the Americas. We used multi-locus sequence data from protein coding loci (ADP-ribosylation factor, H antigen precursor, and delta-9 fatty acid desaturase), DNA barcoding (ITS1/2+5.8s), AFLP markers and mating type analysis to determine the genetic diversity, population structure and recognise the existence of different phylogenetic species among 436 isolates of Histoplasma obtained globally. Our study describes new phylogenetic species and the molecular characteristics of Histoplasma lineages causing outbreaks with a high number of severe outcomes in Northeast Brazil between 2011 and 2015. Genetic diversity levels provide evidence for recombination, common ancestry and clustering of Brazilian isolates at different geographic scales with the emergence of LAm C, a new genotype assigned to a separate population cluster in Northeast Brazil that exhibited low diversity indicative of isolation. The global survey revealed that the high genetic variability among Brazilian isolates along with the presence of divergent cryptic species and/or genotypes may support the hypothesis of Brazil being the center of dispersion of Histoplasma in South America, possibly with the contribution of migratory hosts such as birds and bats. Outside Brazil, the predominant species depends on the region. We confirm that histoplasmosis has significantly broadened its area of occurrence, an important feature of emerging pathogens. From a practical point of view, our data point to the emergence of histoplasmosis caused by a plethora of genotypes, and will enable epidemiological analysis focused on understanding the processes that lead to histoplasmosis. Further, the description of this diversity opens avenues for comparative genomic studies, which will allow progress toward a consensus taxonomy, improve understanding of the presence of hybrids in natural populations of medically relevant fungi, test reproductive barriers and to explore the significance of this variation