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Population structure and evolutionary origins of Microsporum canis, M. ferrugineum and M. audouinii.Infection, Genetics and Evolution :... Sep 2004The recurrent evolutionary emergence of asexual lineages within sexual zoo- and anthropophilic dermatophyte species living in animal-frequented soil is likely to be...
The recurrent evolutionary emergence of asexual lineages within sexual zoo- and anthropophilic dermatophyte species living in animal-frequented soil is likely to be triggered by changes in ecological niche, i.e., shifts of host animal. Subsequent adaptation to the new host species is noted. Sometimes geographic isolation or intrinsic host factors like human race may also play a role in speciation. In the present study, we elaborate concepts of speciation in dermatophytes using the Microsporum canis complex as an example. The group consists of a cluster of phylogenetically closely related anamorphs: the anthropophilic taxa Microsporum audouinii and M. ferrugineum, and the zoophilic taxon M. canis. The sexually reproducing species underlying this complex is Arthroderma otae. The study is done by an analysis of the population structure of about 200 isolates and using intergenic spacers, non-translated regions of genes as well as hypervariable microsatellite markers that are known to evolve at high mutation rates. The results suggest that sympatric speciation took place already during the period where mating ability was maintained and thus that strictly clonal fungal species emerged in Africa and led to genetically isolated clonal species elsewhere.
Topics: Alleles; Animals; Base Sequence; Biological Evolution; Genes, Fungal; Genotype; Humans; Microsatellite Repeats; Microsporum; Molecular Sequence Data; Phylogeny; Polymorphism, Genetic; Sequence Alignment
PubMed: 15450196
DOI: 10.1016/j.meegid.2003.12.004 -
Journal of the American Academy of... Feb 2017
Topics: Child, Preschool; Dermoscopy; Humans; Male; Microscopy, Ultraviolet; Tinea Capitis
PubMed: 28087021
DOI: 10.1016/j.jaad.2016.05.018 -
International Journal of Molecular... Feb 2024is a widely distributed dermatophyte, which is among the main etiological agents of dermatophytosis in humans and domestic animals. This fungus invades, colonizes and... (Review)
Review
is a widely distributed dermatophyte, which is among the main etiological agents of dermatophytosis in humans and domestic animals. This fungus invades, colonizes and nourishes itself on the keratinized tissues of the host through various virulence factors. This review will bring together the known information about the mechanisms, enzymes and their associated genes relevant to the pathogenesis processes of the fungus and will provide an overview of those virulence factors that should be better studied to establish effective methods of prevention and control of the disease. Public databases using the MeSH terms "", "virulence factors" and each individual virulence factor were reviewed to enlist a series of articles, from where only original works in English and Spanish that included relevant information on the subject were selected. Out of the 147 articles obtained in the review, 46 were selected that reported virulence factors for in a period between 1988 and 2023. The rest of the articles were discarded because they did not contain information on the topic (67), some were written in different languages (3), and others were repeated in two or more databases (24) or were not original articles (7). The main virulence factors in are keratinases, fungilisins and subtilisins. However, less commonly reported are biofilms or dipeptidylpeptidases, among others, which have been little researched because they vary in expression or activity between strains and are not considered essential for the infection and survival of the fungus. Although it is known that they are truly involved in resistance, infection and metabolism, we recognize that their study could strengthen the knowledge of the pathogenesis of with the aim of achieving effective treatments, as well as the prevention and control of infection.
Topics: Humans; Animals; Virulence Factors; Microsporum; Animals, Domestic; Subtilisins
PubMed: 38473782
DOI: 10.3390/ijms25052533 -
Advanced Biomedical Research 2020Dermatophytosis is mostly caused by dermatophytes species, and the diagnosis of disease is very important for early treatment. The aim of this study was to identify the...
BACKGROUND
Dermatophytosis is mostly caused by dermatophytes species, and the diagnosis of disease is very important for early treatment. The aim of this study was to identify the commonly dermatophytes species isolated directly from the clinical samples, using the polymerase chain reaction (PCR) and evaluate both conventional and molecular methods.
MATERIALS AND METHODS
This study was performed on 115 clinical samples. Dermatophyte isolates were initially identified by conventional method and confirmed by the sequencing molecular method. In this study, the molecular technique is implemented directly on clinical samples. Statistical analysis of the information was performed by the SPSS software, and the results were statistically analyzed.
RESULTS
Our findings demonstrated that the most abundant dermatophyte species by PCR-sequencing were (20%), followed by (10%), (6.7%), (6.7%), , and , (3.3%) for each one.
CONCLUSION
For medical laboratories, routine procedures are still preferred because of their lower cost, and the results are almost the same as the molecular methods. The sensitivity and specificity values for PCR under our laboratory condition were 60% and 87%, respectively. This study shows that molecular results performed better in nails than other samples, by culture results.
PubMed: 33457339
DOI: 10.4103/abr.abr_21_20 -
Journal of Fungi (Basel, Switzerland) Jun 2022is the primary agent causing dermatophytosis in cats, and also infects humans, dogs, and other species. Assessment of genetic variation among isolates in the United...
is the primary agent causing dermatophytosis in cats, and also infects humans, dogs, and other species. Assessment of genetic variation among isolates in the United States has not been conducted. Further, mating type and assessment of disease severity associated with genotypic characteristics have not been rigorously evaluated. We therefore isolated from 191 domestic cats across the US and characterized genotypes by evaluation of ITS sequence, MAT locus, and microsatellite loci analysis. The genes SSU1 and SUB3, which are associated with keratin adhesion and digestion, were sequenced from a subset of isolates to evaluate potential genetic associations with virulence. Analysis of microsatellite makers revealed three genetic clusters. Both clinic location and disease severity were significant predictors of microsatellite variants. 100% of the isolates were MAT1-1 mating gene type, indicating that MAT1-2 is very rare or extinct in the US and that asexual reproduction is the dominant form of replication. No genetic variation at SSU1 and SUB3 was observed. These findings pave the way for novel testing modalities for and provide insights about transmission and ecology of this ubiquitous and relatively uncharacterized agent.
PubMed: 35887433
DOI: 10.3390/jof8070676 -
Mycopathologia Oct 2023
Topics: Humans; Scalp; Eyebrows; Microsporum; Tinea; Tinea Capitis
PubMed: 36310333
DOI: 10.1007/s11046-022-00681-2 -
The Journal of Pediatrics May 2022
Topics: Disease Outbreaks; Humans; Microsporum; Tinea
PubMed: 34953818
DOI: 10.1016/j.jpeds.2021.12.034 -
Frontiers in Cellular and Infection... 2023Previous studies have shown that natural polyacetylene alcohols, such as falcarindiol (FADOH), have good antifungal effects on plant fungi. While its effect on fungi...
Previous studies have shown that natural polyacetylene alcohols, such as falcarindiol (FADOH), have good antifungal effects on plant fungi. While its effect on fungi that infect humans remains to be explored. In our study, checkerboard microdilution, drop-plate assay, and time-growth method were employed to analyze the interactions between FADOH and itraconazole (ITC) against dermatophytes, including 12 (), 12 (), and 6 (). The results showed that the combination of FADOH and ITC exhibited synergistic and additive activity against 86.7% of all tested dermatophytes. FADOH had an excellent synergistic effect on ITC against and ; the synergistic rates were 66.7% and 58.3%, respectively. On the contrary, FADOH combined with ITC showed poor synergistic inhibitory activity (16.7%) against . Moreover, the additive rates of these two drugs against , , and were 25%, 41.7%, and 33.3%, respectively. No antagonistic interactions were observed. The drop-plate assay and time-growth curves confirmed that the combination of FADOH and ITC had a potent synergistic antifungal effect. The synergistic effect of FADOH and ITC against dermatophytes is reported here for the first time. Our findings suggest the potential use of FADOH as an effective antifungal drug in the combined therapy of dermatophytoses caused especially by and .
Topics: Humans; Itraconazole; Antifungal Agents; Arthrodermataceae; Microbial Sensitivity Tests; Trichophyton
PubMed: 37207188
DOI: 10.3389/fcimb.2023.1128000 -
Transplant Infectious Disease : An... Jun 2021Microsporum canis is a dermatophyte known to cause superficial skin infections. In immunocompromised patients, it can lead to invasive dermatophytosis. We present a case... (Review)
Review
Microsporum canis is a dermatophyte known to cause superficial skin infections. In immunocompromised patients, it can lead to invasive dermatophytosis. We present a case of biopsy-proven left knee mycetoma caused by M canis in a renal transplant patient. Identification of M canis was achieved via sequencing of the internal transcribed spacer regions. Treatment involved surgical debridement, oral posaconazole, and reduction in immunosuppression. In addition, we provide a review of current literature on invasive M canis infections.
Topics: Arthrodermataceae; Dermatomycoses; Humans; Kidney Transplantation; Microsporum; Mycetoma
PubMed: 33217133
DOI: 10.1111/tid.13516 -
Development, preparation, and evaluation of a novel non-adjuvanted polyvalent dermatophytes vaccine.Scientific Reports Jan 2023Ringworm is a worldwide distributed contagious disease infecting both man and animals that constitute an economic, zoonotic, and health problem concern all over the...
Ringworm is a worldwide distributed contagious disease infecting both man and animals that constitute an economic, zoonotic, and health problem concern all over the world. During the last decade, attention has been directed to vaccination as an ideal approach to the control of such diseases. In the present study, non-adjuvanted polyvalent vaccines were prepared from locally isolated hot and virulent dermatophyte species, namely Trichophyton verrucosum (T. verrucosum), Trichophyton mentagrophytes (T. mentagrophytes), and Microsporum canis (M. canis) were immunologically evaluated. The prepared vaccine evaluation was focused on the aspects of immunogenicity and protective efficacy using guinea pigs. Both in its living or inactivated forms, the vaccine-induced significant humoral and cell-mediated immune responses and achieve proper protection of guinea pigs against challenging infections with homologous and heterologous dermatophyte strains. On the other hand, investigations on dermatophyte exo-keratinases showed that it was better produced and more expressed in a mineral-based medium containing pure keratin (3 g/L) than in the same medium with human hair supplementation (2.6 g/L). The maximum dermatophyte productivity of exo-keratinases was found to be between 18 and 21 days post-incubation. Using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), two fractions with molecular weights of 40 kDa (fraction I) and 28 kDa (fraction II) have been identified in the culture filtrate of the three involved dermatophyte species. Both fractions demonstrated keratinolytic activity. The specific activity of the isolated keratinases (number of Keratinase units (KU)/mg protein) was stronger in fraction I, where it reached 18.75, 15.38, and 14 KU/mg protein as compared to 12.9, 8.74, and 12 KU/mg protein in fraction II of T. verrucosum, T. mentagrophytes, and M. canis, respectively. The dermatophyte exo-keratinases proved to be immunogenic as they stimulated high keratinase-specific antibody titers and induced strong delayed skin hypersensitivity reactions in vaccinated animals. Anti-keratinase-specific IgG was detected in sera of guinea pigs immunized with the inactivated or living polyvalent dermatophyte vaccines by a homemade enzyme-linked immunosorbent assay (ELISA) using dermatophyte exo-keratinases as coating antigen. The intradermal injection of dermatophyte exo-keratinases induced specific delayed skin reactions in guinea pigs immunized with the inactivated or the living polyvalent dermatophyte vaccines. The intradermal injection of dermatophyte exo-keratinases in the control non-sensitized guinea pigs was associated with itching, swelling, and bloody scar formation, however, no skin indurations were formed. The development of those post-exo-keratinases injection reactions in the control non-sensitized apparently healthy guinea pigs group, suggests an exo-keratinases possible role in the pathogenesis of dermatophytosis.
Topics: Male; Humans; Animals; Guinea Pigs; Arthrodermataceae; Dermatomycoses; Vaccines, Combined; Microsporum
PubMed: 36599863
DOI: 10.1038/s41598-022-26567-3