Mycopathologia最新文献

The opportunistic black yeast-like fungus Exophiala dermatitidis frequently colonizes the respiratory tract of cystic fibroses (CF) patients. Additionally, it can cause superficial, systemic, and cerebral forms of phaeohyphomycoses. The objective of this study was to develop and apply a microsatellite or short tandem repeat (STR) genotyping scheme for E. dermatitidis. In total, 82 E. dermatitidis isolates from various geographic origins (environmental = 9, CF = 63, invasive isolates = 9, melanin-deficient mutant = 1) were included in this study. After next-generation sequencing of a reference strain and sequence filtering for microsatellites, six STR markers were selected and amplified in two multiplex PCR reactions. The included isolates were discriminated in a genetic cluster analysis using the Pearson algorithm to reveal the relatedness of the isolates. The E. dermatitidis isolates clustered on basis of both, their source and their origin. The invasive isolates from Asia were unrelated to isolates from CF. Nearly all environmental isolates were grouped separately from patients' isolates. The Simpson index was 0.94. In conclusion, we were able to establish a STR genotyping scheme for investigating population genomics of E. dermatitidis.

Background: Recently, the prevalence of invasive fungal infections has been on the rise, and one of the prevalent symptoms frequently observed is bone deterioration and bone loss.

Materials and methods: Using an in vitro model we studied how Aspergillus fumigatus invades the bone. Pathological analysis was then employed to observe the structure and distinctive features of the invading fungal elements within the bone invasion model. Meanwhile, the antifungal effects of itraconazole, voriconazole, posaconazole, and amphotericin B were evaluated.

Results: The pathological findings showed that in the experimental group, fungal spores and hyphae invaded the bone tissue or were observed growing in the vicinity of the bone edge tissues, as indicated by both HE and PAS staining. In contrast, no fungal elements were observed in the control group, indicating that the in vitro bone invasion model of A. fumigatus was successfully constructed. Furthermore, the findings from the antifungal sensitivity test demonstrated that the lowest effective concentrations of antifungal drugs against the bone invasion model were as follows: 4 μg/ml for itraconazole, 0.5 μg/ml for voriconazole, 2 μg/ml for posaconazole, and 2 μg/ml for amphotericin B.

Discussion: The successful construction of the bone invasion model of A. fumigatus has provided a solid basis for future investigations into the mechanisms underlying A. fumigatus bone invasion and the study of its virulence factors. Utilizing bone models is of utmost importance in advancing the development of novel antifungal treatment approaches, as well as in effectively preventing and treating fungal bone invasion and osteolytic diseases.

Trichphyton indotineae, a species newly designated in 2020 independent of T. interdigitale, comprises highly terbinafine (TRF)-resistant dermatophytosis that is epidemic in North India and spreding to worldwide. Some clinical isolates of T. indotineae have been resistance both TRF and azoles that might be caused the treatment failure. To detect the azole resistance strains, we developed a long amplification PCR (LA-PCR) detection method for the tandem repeat of the CYP51B (encoding sterol 14a-demethylase gene) in T. indotineae. Contrasting the drug susceptibility test results with the LA-PCR results confirmed a trend toward low susceptibility to azole antifungal agents in strains with amplifications of 9.5 kbp or greater (3 or more copies of CYP51B). Our results suggest that the method could be detected rapidly of low-susceptibility strains to azole antifungal agents.

Intravascular diseases due to Candida species, including endocarditis and cardiac device-associated infections, are rare yet devastating manifestations of invasive candidiasis affecting an already vulnerable population. Despite their significant associated morbidity and mortality, limited prospective data exist to inform the optimal diagnostic and therapeutic approaches to these entities. Herein, we review the existing literature pertaining to the epidemiology, diagnosis, and management of infectious endocarditis, rhythm management device infections, and circulatory support device infections caused by Candida species and suggest areas for future research.