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BackgroundThe human gut mycobiome, a minor but integral component of the gut microbiome, has emerged as a significant player in host homeostasis and disease development. While bacteria have traditionally been the focus of gut microbiome studies, recent evidence suggests that fungal communities (mycobiota) may also play a crucial role in modulating health, particularly in neuropsychiatric disorders.ObjectiveThis review aims to provide a comprehensive overview of current knowledge on the relationship between the gut mycobiome and neuropsychiatric disorders, exploring the potential of targeting fungal communities as a novel therapeutic strategy.MethodsWe summarized recent findings from metagenomic analyses that characterize the diversity and composition of gut mycobiota and discuss how these communities interact with the host and other microorganisms via the gut-brain axis. Key methodologies for studying mycobiota, such as high-throughout sequencing and bioinformatics approaches, were also reviewed to highlight advances in the field.ResultsEmerging research links gut mycobiota dysbiosis to conditions such as schizophrenia, Alzheimer’s disease, autism spectrum disorders, bipolar disorder, and depression. Studies indicate that specific fungal populations, such as Candida and Saccharomyces, may influence neuroinflammation, gut permeability and immune responses, thereby affecting mental health outcomes.ConclusionUnderstanding the gut mycobiome’s role in neuropsychiatric disorders opens new avenues for therapeutic interventions, including antifungal treatments, probiotics, and dietary modifications. Future research should integrate multi-omics approaches to unravel the complex interkingdom interactions within the gut ecosystem, paving the way for personalized medicine in mental health care.

The interplay between human microbiota and various physiological systems has garnered significant attention in recent years. The gut microbiota plays a critical role in maintaining physiological homeostasis and influences various aspects of human health, particularly via the gut brain axis. Since 2017, the challenging concept of the gut-retina axis has emerged thanks to a network analysis emphasizing the potential role of the gut microbiota disruption in the development of the age-related macular degeneration and further retinal damages. Many other ocular disorders have been linked to the dysbiosis of the gut microbiota, including uveitis and glaucoma. It has been shown that age related macular degeneration can be prevented or reversed using a diet that induces changes in the gut microbiota. The potential link between the gut microbiota as well as others types of microbiota such as the ocular surface microbiota and the development/progression of age related as well as inherited retinal degenerations and other degenerative eye diseases, has recently been broadened. Therefore, the pathogenesis of several eye diseases has recently been associated with a larger perception called the gut eye axis. This mini-review examines the potential mechanisms underlying the gut eye axis and suggests implications for the management of eye diseases. By understanding the modulation of the gut microbiota and its impact on eye disease, this mini-review provides insight into potential therapeutic interventions and avenues for future research.

Abstract Background The ubiquitous environmental fungus Aspergillus flavus is also a life‐threatening avian pathogen. Objectives This study aimed to assess the genetic diversity and population structure of A. flavus isolated from turkey lung biopsy or environmental samples collected in a poultry farm. Methods A. flavus isolates were identified using both morphological and ITS sequence features. Multilocus microsatellite genotyping was performed by using a panel of six microsatellite markers. Population genetic indices were computed using FSTAT and STRUCTURE. A minimum‐spanning tree (MST) and UPGMA dendrogram were drawn using BioNumerics and NTSYS‐PC, respectively. Results The 63 environmental (air, surfaces, eggshells and food) A. flavus isolates clustered in 36 genotypes (genotypic diversity = 0.57), and the 19 turkey lung biopsies isolates clustered in 17 genotypes (genotypic diversity = 0.89). The genetic structure of environmental and avian A. flavus populations were clearly differentiated, according to both F‐statistics and Bayesian model‐based analysis’ results. The Bayesian approach indicated gene flow between both A. flavus populations. The MST illustrated the genetic structure of this A. flavus population split in nine clusters, including six singletons. Conclusions Our results highlight the distinct genetic structure of environmental and avian A. flavus populations, indicative of a genome‐based adaptation of isolates involved in avian aspergillosis.

The molecular characterization of Malassezia spp. isolates from animals and humans has not been thoroughly studied. Although a range of molecular methods has been developed for diagnosing Malassezia species, they have several drawbacks, such as inefficiency in differentiating all the species, high cost and questionable reproducibility. The present study aimed to develop VNTR markers for genotyping Malassezia isolated from clinical and animal samples. A total of 44 M. globosa and 24 M. restricta isolates were analyzed. Twelve VNTR markers were selected on seven different chromosomes (I, II, III, IV, V, VII and IX), six for each Malassezia species. The highest discriminatory power for a single locus was obtained with the STR-MG1 marker (0.829) and STR-MR2 marker (0.818) for M. globosa and M. restricta, respectively. After the analysis of multiple loci, 24 genotypes were noted among 44 isolates in M. globosa, with a discrimination index D of 0.943 and 15 genotypes were noted among 24 isolates in M. restricta, with a discrimination index D of 0.967. An endogenous infection was detected in two patients. Different genotypes of M. globosa strains colonized one patient. Interestingly, VNTR markers analysis revealed a carriage between a breeder and his dog in three cases for M. globosa and two for M. restricta. The FST (0.018 to 0.057) values indicate a low differentiation between the three populations of M. globosa. These results suggest a dominant clonal mode of reproduction in M. globosa. The typing of M. restricta showed a genotypic diversity of the strains, which can cause various skin pathologies. However, patient five was colonized with strains having the same genotype collected from different body parts (back, shoulder). VNTR analysis was capable of identifying species with high accuracy and reliability. More importantly, the method would facilitate monitoring Malassezia colonization in domestic animals and humans. It was shown that the patterns are stable and the method is discriminant, making it a powerful tool for epidemiological purposes.

Abstract Background The aim of this study was to determine the biofilm formation, the extracellular enzymatic activities of 182 clinical isolates of the Candida parapsilosis complex. Methods Molecular identification of the C. parapsilosis species complex was performed using PCR RFLP of SADH gene and PCR sequencing of ITS region. The susceptibility of ours isolates to antifungal agents and molecular mechanisms underlying azole resistance were evaluated. Results 63.5% of C. parapsilosis were phospholipase positive with moderate activity for the majority of strains. None of the C. metapsilosis or C. orthopsilosis isolates was able to produce phospholipase. Higher caseinase activities were detected in C. parapsilosis (Pz = 0.5 ± 0.18) and C. orthopsilosis (Pz = 0.49 ± 0.07) than in C. metapsilosis isolates (Pz = 0.72 ± 0.1). 96.5% of C. parapsilosis strains and all isolates of C. metapsilosis and C. orthopsilosis produced gelatinase. All the strains possessed the ability to show haemolysis on blood agar. C. metapsilosis exhibited the low haemolysin production with statistical significant differences compared to C. parapsilosis and C. orthopsilosis. The biofilm forming ability of C. parapsilosis was highly strain dependent with important heterogeneity, which was less evident with both C. orthopsilosis and C. metapsilosis. Some C. parapsilosis isolates met the criterion for susceptible dose dependent to fluconazole (10.91%), itraconazole (16.36%) and voriconazole (7.27%). Moreover, 5.45% and 1.82% of C. parapsilosis isolates were respectively resistant to fluconazole and voriconazole. All strains of C. metapsilosis and C. orthopsilosis were susceptible to azoles; and isolates of all three species exhibited 100% of susceptibility to caspofungin, amphotericin B and 5-flucytosine. Conclusions A combination of molecular mechanisms, including the overexpression of ERG11, and genes encoding efflux pumps (CDR1, MDR1, and MRR1) were involved in azole resistance in C. parapsilosis.

Abstract: We report a case of otomycosis caused by the Graphium stage of Pseudallescheria apiosperma in an immunocompetent 32 years old man who was suffering from hypoacusia and purulent otorrhea. Isolates were identified as Graphium stage of Pseudallescheria sp. on the basis of macroscopic and microscopic characteristics. Pseudallescheria apiosperma was correctly identified by PCR sequencing of ITS regions and β-tubulin gene. In this case the contamination could be due to intensive activity of gardening with poor hygiene. [Copyright &y& Elsevier]

Aspergillus flavus is second only to A. fumigatus in causing invasive aspergillosis and it is the major agent responsible for fungal sinusitis, keratitis and endophthalmitis in many countries in the Middle East, Africa and Southeast Asia. Despite the growing challenge due to A. flavus, data on the molecular epidemiology of this fungus remain scarce. The objective of the present study was to develop a new typing method based on the detection of VNTR (Variable number tandem repeat) markers. Eight VNTR markers located on 6 different chromosomes (1, 2, 3, 5, 7 and 8) of A. flavus were selected, combined by pairs for multiplex amplifications and tested on 30 unrelated isolates and six reference strains. The Simpson index for individual markers ranged from 0.398 to 0.818. A combined loci index calculated with all the markers yielded an index of 0.998. The MLVA (Multiple Locus VNTR Analysis) technique proved to be specific and reproducible. In a second time, a total of 55 isolates from Chinese avian farms and from a Tunisian hospital have been evaluated. One major cluster of genotypes could be defined by using the graphing algorithm termed Minimum Spanning Tree. This cluster comprised most of the isolates collected in an avian farm in southern China. The MLVA technique should be considered as an excellent and cost-effective typing method that could be used in many laboratories without the need for sophisticated equipment.