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BioRxiv : the Preprint Server For... Mar 2023Pancreatic ductal adenocarcinoma (PDAC) is a poor prognosis cancer with an .aggressive growth profile that is often diagnosed at late stage and that has few curative or...
Pancreatic ductal adenocarcinoma (PDAC) is a poor prognosis cancer with an .aggressive growth profile that is often diagnosed at late stage and that has few curative or therapeutic options. PDAC growth has been linked to alterations in the pancreas microbiome, which could include the presence of the fungus . We used RNA-sequencing to compare 14 paired tumor and normal (tumor adjacent) pancreatic cancer samples and found RNA in both the PDAC and normal tissues. Although the presence of was not correlated with tumor growth, a set of immune- and inflammatory-related genes were up-regulated in the PDAC compared to the normal samples, suggesting that they are involved in tumor progression. Gene set enrichment analysis suggests that activation of the complement cascade pathway and inflammation could be involved in pro PDAC growth.
PubMed: 37034706
DOI: 10.1101/2023.03.28.534606 -
Journal of Dental Research Jun 2020A broad range of fungi has been detected in molecular surveys of the oral mycobiome. However, knowledge is still lacking on interindividual variability of these...
A broad range of fungi has been detected in molecular surveys of the oral mycobiome. However, knowledge is still lacking on interindividual variability of these communities and the ecologic and clinical significance of oral fungal commensals. In this cross-sectional study, we use internal transcribed spacer 1 amplicon sequencing to evaluate the salivary mycobiome in 59 subjects, 36 of whom were scheduled to receive cancer chemotherapy. Analysis of the broad population structure of fungal communities in the whole cohort identified 2 well-demarcated genus-level community types (mycotypes), with and as the main taxa driving cluster partitioning. The mycotype had lower diversity than the mycotype and was positively correlated with cancer and steroid use in these subjects, smoking, caries, utilizing a removable prosthesis, and plaque index. Mycotypes were also associated with metabolically distinct bacteria indicative of divergent oral environments, with aciduric species enriched in the mycotype and inflammophilic bacteria increased in the mycotype. Similar to their fungal counterparts, coexisting bacterial communities associated with the mycotype showed lower diversity than those associated with the mycotype, suggesting that common environmental pressures affected bacteria and fungi. Mycotypes were also seen in an independent cohort of 24 subjects, in which cultivation revealed as viable oral mycobiome members, although the low-abundance was the only species recovered. There was a high degree of concordance between the molecular detection and cultivability of , while cultivation showed low sensitivity for detection of the mycotype. Overall, our work provides insights into the oral mycobiome landscape, revealing 2 community classes with apparently distinct ecologic constraints and specific associations with coexisting bacteria and clinical parameters. The utility of mycotypes as biomarkers for oral diseases warrants further study.
Topics: Adult; Aged; Bacteria; Cross-Sectional Studies; Female; Fungi; Humans; Malassezia; Male; Middle Aged; Mycobiome
PubMed: 32315566
DOI: 10.1177/0022034520915879 -
Virulence Apr 2017Skin constantly encounters external elements, including microbes. Culture-based studies have identified fungi present on human skin and have linked some species with... (Review)
Review
Skin constantly encounters external elements, including microbes. Culture-based studies have identified fungi present on human skin and have linked some species with certain skin diseases. Moreover, modern medical treatments, especially immunosuppressants, have increased the population at risk for cutaneous and invasive fungal infections, emphasizing the need to understand skin fungal communities in health and disease. A major hurdle for studying fungal flora at a community level has been the heterogeneous culture conditions required by skin fungi. Recent advances in DNA sequencing technologies have dramatically expanded our knowledge of the skin microbiome through culture-free methods. This review discusses historical and recent research on skin fungal communities - the mycobiome - in health and disease, and challenges associated with sequencing-based mycobiome research.
Topics: Fungi; Health; Humans; Microbiota; Mycobiome; Mycoses; Skin
PubMed: 27754756
DOI: 10.1080/21505594.2016.1249093 -
FEMS Yeast Research Oct 2021Malassezia furfur is a yeast species belonging to Malasseziomycetes, Ustilaginomycotina and Basidiomycota that is found on healthy warm-blooded animal skin, but also...
Malassezia furfur is a yeast species belonging to Malasseziomycetes, Ustilaginomycotina and Basidiomycota that is found on healthy warm-blooded animal skin, but also involved in various skin disorders like seborrheic dermatitis/dandruff and pityriasis versicolor. Moreover, Malassezia are associated with bloodstream infections, Crohn's disease and pancreatic carcinoma. Recent advances in Malassezia genomics and genetics have focused on the nuclear genome. In this work, we present the M. furfur mitochondrial (mt) genetic heterogenicity with full analysis of 14 novel and six available M. furfur mt genomes. The mitogenome analysis reveals a mt gene content typical for fungi, including identification of variable mt regions suitable for intra-species discrimination. Three of them, namely the trnK-atp6 and cox3-nad3 intergenic regions and intron 2 of the cob gene, were selected for primer design to identify strain differences. Malassezia furfur strains belonging to known genetic variable clusters, based on AFLP and nuclear loci, were assessed for their mt variation using PCR amplification and sequencing. The results suggest that these mt regions are excellent molecular markers for the typing of M. furfur strains and may provide added value to nuclear regions when assessing evolutionary relationships at the intraspecies level.
Topics: Amplified Fragment Length Polymorphism Analysis; Animals; Genome, Mitochondrial; Malassezia; Mitochondria; Tinea Versicolor
PubMed: 34562093
DOI: 10.1093/femsyr/foab051 -
Infection and Immunity Jan 2022The human skin is our outermost layer and serves as a protective barrier against external insults. Advances in next-generation sequencing have enabled the discoveries of...
The human skin is our outermost layer and serves as a protective barrier against external insults. Advances in next-generation sequencing have enabled the discoveries of a rich and diverse community of microbes-bacteria, fungi, and viruses that are residents of this surface. The genomes of these microbes also revealed the presence of many secretory enzymes. In particular, proteases which are hydrolytic enzymes capable of protein cleavage and degradation are of special interest in the skin environment, which is enriched in proteins and lipids. In this minireview, we will focus on the roles of these skin-relevant microbial secreted proteases, in terms of both their widely studied roles as pathogenic agents in tissue invasion and host immune inactivation and their recently discovered roles in intermicrobial interactions and modulation of virulence factors. From these studies, it has become apparent that while microbial proteases are capable of a wide range of functions, their expression is tightly regulated and highly responsive to the environments the microbes are in. With the introduction of new biochemical and bioinformatics tools to study protease functions, it will be important to understand the roles played by skin microbial secretory proteases in cutaneous health, especially the less studied commensal microbes with an emphasis on contextual relevance.
Topics: Bacteria; Biomarkers; Disease Susceptibility; Endopeptidases; Fungi; Host Microbial Interactions; Host-Pathogen Interactions; Humans; Microbiota; Skin; Virulence Factors
PubMed: 34606369
DOI: 10.1128/IAI.00397-21 -
Journal of Fungi (Basel, Switzerland) Feb 2022The fungal kingdom comprises ubiquitous forms of life with 1.5 billion years, mostly phytopathogenic and commensals for humans and animals. However, in the presence of... (Review)
Review
The fungal kingdom comprises ubiquitous forms of life with 1.5 billion years, mostly phytopathogenic and commensals for humans and animals. However, in the presence of immune disorders, fungi may cause disease by intoxicating, infecting or sensitizing with allergy. Species from the genera , and , as well as dermatophytes from the genera , and , are the most commonly implicated in veterinary medicine. and stand as the most commonly associated with either allergy or infection in animals, immediately followed by , while dermatophytes are usually associated with the ringworm skin infection. By aiming at the relevance of fungi in veterinary allergy it was concluded that further research is still needed, especially in the veterinary field.
PubMed: 35330237
DOI: 10.3390/jof8030235 -
The Journal of Veterinary Medical... Mar 2023Canine Malassezia dermatitis and otitis externa are generally treated by antifungal drugs. However, multi-drug-resistant strains of Malassezia pachydermatis have been...
Canine Malassezia dermatitis and otitis externa are generally treated by antifungal drugs. However, multi-drug-resistant strains of Malassezia pachydermatis have been reported worldwide. Given the presence of these multi-drug-resistant strains, it is unclear which antifungal agent is the most effective for canine Malassezia dermatitis and canine otitis. In this study, we attempted to determine the most effective drug against azole-resistant M. pachydermatis. Susceptibility to azoles and terbinafine (TBF) was assessed using a modified broth microdilution method. In all tested isolates, the minimum inhibitory concentration at 90% of organisms (MIC) were 16 to >32 μg/mL for the azoles, and 2 μg/mL for TBF. All of the strains that showed low susceptibility to both itraconazole and miconazole were also relatively susceptible to TBF.
Topics: Animals; Dogs; Azoles; Terbinafine; Malassezia; Japan; Antifungal Agents; Microbial Sensitivity Tests; Dermatitis; Dog Diseases
PubMed: 36724970
DOI: 10.1292/jvms.22-0358 -
Journal of Fungi (Basel, Switzerland) Jun 2020is a yeast inhabiting the skin and ear canals in healthy dogs. In the presence of various predisposing conditions it can cause otitis and dermatitis, which are treated... (Review)
Review
is a yeast inhabiting the skin and ear canals in healthy dogs. In the presence of various predisposing conditions it can cause otitis and dermatitis, which are treated with multiple antifungal agents, mainly azole derivatives. This manuscript aims to review the available evidence regarding the occurrence of resistance phenomena in this organism. Various findings support the capacity of for developing resistance. These include some reports of treatment failure in dogs, the reduced antifungal activity found against yeast isolates sampled from dogs with exposure to antifungal drugs and strains exposed to antifungal agents in vitro, and the description of resistance mechanisms. At the same time, the data reviewed may suggest that the development of resistance is a rare eventuality in canine practice. For example, only three publications describe confirmed cases of treatment failure due to antifungal resistance, and most claims of resistance made by past studies are based on interpretive breakpoints that lack sound support from the clinical perspective. However, it is possible that resistant cases are underreported in literature, perhaps due to the difficulty of obtaining a laboratory confirmation given that a standard procedure for susceptibility testing of is still unavailable. These considerations highlight the need for maintaining surveillance for the possible emergence of clinically relevant resistance, hopefully through a shared strategy put in place by the scientific community.
PubMed: 32630397
DOI: 10.3390/jof6020093 -
Frontiers in Medicine 2024
PubMed: 38868748
DOI: 10.3389/fmed.2024.1431191 -
Dermatology Online Journal Feb 2017Tinea versicolor (TV) is typically an asymptomatic fungal infection of the stratum corneum owing to Malassezia overgrowth. It presents as hypo or hyperpigmented macules...
Tinea versicolor (TV) is typically an asymptomatic fungal infection of the stratum corneum owing to Malassezia overgrowth. It presents as hypo or hyperpigmented macules with fine scale that coalesce into patches on the trunk, neck, and/or arms. Presented in this report is a 34-year-old man with an interesting case of folliculocentric tinea versicolor manifesting as perifollicular hypopigmented macules on the lower back.
Topics: Adult; Hair Follicle; Humans; Hypopigmentation; Male; Tinea Versicolor
PubMed: 28329492
DOI: No ID Found