Dermatophytes are fungi capable of digesting keratin and able to infect the skin surface of animal. Among them, the anthropophilic species Trichophyton rubrum is the most important human pathogen in Japan as the cusetive species of tinea lesions. The lesions caused by this fungus are known to be mild in their inflammatory reaction.
More than 20% of the Japanese population is believed to be suffering from tinea pedis and the situation have not changed despite the introduction of new potent antifungal drugs.
Several attempts made to cultivate the fungus on the skin surface has revealed the presence of pathogenic dermatophytes in healthy looking skin around a lesion or on the skin of surrounding individuals. Also, more than half of tinea pedis patients are left untreated or are treated intermittently only when the patient has noticed uncomfortable symptoms due to a lesion.
The low QOL impairment due to tinea pedis lesions by anthropophilic dermatophytes is one reason preventing complete cure and has resulted in a growing number of tinea pedis patients, especially among the aged.
To achieve control of the infections by anthroppphilic dermatophytes, the ecological background of the causative fungi should be taken under consideration rather than their eradication.

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I(the author), Tadahiko Matsumoto, who is a winner of the 2008 Japanese Society for Medical Mycology(JSMM)Award, was born in 1945 and graduated in 1969 from Kyushu University in Fukuoka, Japan with an M.D. degree. At the Department of Dermatology, Kyushu University I studied dermatology and medical mycology. In Tokyo(1970-1971)at the Department of Microbiology, National Institute of Hygienic Sciences I learned general mycology. During the period from 1981 to 1983 I further studied medical mycology at the Division of Mycotic Diseases(Director: Dr. Libero Ajello), Center for Infectious Diseases, Centers for Disease Control(CDC)in Atlanta, Georgia in the United States. During the period from 1991 to 2005 while working as Director of Dermatology of Toshiba Hospital in Tokyo I was affiliated with several medical schools as a clinical and adjunct professor.
Being a unique physician-scientist eager to publish my manuscripts in highly-regarded mycology journals, my studies were accurately reported as to description, taxonomy, and identification. My articles were published in journals carefully chosen for my purposes. As I became better known, I was frequently invited to contribute review articles in leading journals and chapters in authoritative textbooks of dermatology, infectious diseases, and microbiology. I was also invited to be a member and/or chairperson of various symposia in international congresses and one of the lecturers in seminars. I have established many friendly personal relationships among scientists, and we are always ready to help each other whenever necessary.

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The fungicidal activities of the thiocarbamate antifungal agent liranaftate were compared to those of luliconazole, amorolfine hydrochloride and ketoconazole against twelve stock strains of three species of dermatophytes.
The MICs of 0.001-0.009μg⁄ml of luliconazole against Trichophyton rubrum (n=6)were the lowest among the agents tested, but its MCCs were considerably higher. Consequently, the antifungal potency of luliconazole was considered fungistatic. In contrast to this, the MCCs of 0.009-0.039μg⁄ml of liranaftate against T. rubrum were the lowest and similar to its MICs. These results showed that liranaftate was fungicidal. All antifungals except ketoconazole tended to be fungicidal against both T. mentagrophytes(n=3)and Microsporum gypseum(n=3).
In time-kill studies, liranaftate showed the greatest decrease to a below detection limit in viable counts of T. rubrum. The degree of killing of the strain by amorolfine was not greater than that seen by liranaftate, and little reduction of the viable counts by luliconazole and ketoconazole was observed irrespective of concentrations of the agents. Conversely, there were no differences among four agents in fungicidal activities against T.mentagrophytes. The killing activities of liranaftate against M. gypseum were also higher than those of comparable agents, as true of T. rubrum described above.
In this study we found that it was harder to kill T. rubrum than other dermatophytes. Therefore, liranaftate with its potent fungicidal activities was suggested an efficacious agent for the treatment of dermatophytes.

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An isolate of Arthroderma simii was successfully mated with a tester strain of A. vanbreuseghemii cultured on the plate of simple agar with some hair on it at 27 °C. Confirmation of sexual reproduction was made by the detection of hybrids of two parental genotypes. The implications of this result are discussed from the viewpoint of a reevaluation of the species boundaries of dermatophytes.

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Up to now, 30 mitochondrial DNA(mtDNA)and 4 rDNA types of Sporothrix schenckii strains have been identified. Here, seventy-six isolates of S. schenckii from Mexico, Guatemala, Brazil, Thailand and India were genotyped and studied epidemiologically by mtDNA restriction fragment length polymorphisms(RFLP)and internal transcribed spacer region(ITS)-RFLP analysis and two new mtDNA types, Type 31 and Type 32, were found. Type 30, previously reported by Mora-Cabrera et al. was confirmed to be Type 3 and designated as blank. Of 48 isolates from Mexico, 41 belonged to Group A wherein Type 2(13 isolates), Type 3(10)and Type 28(7)were dominant. All ten isolates from India and Thailand belonged to Group B. The 52 Group A and 24 Group B isolates corresponded to rDNA Type I and Type IV , respectively, reported by Watanabe et al.(Nippon Ishinkin Gakkai Zasshi 45: 165-175, 2004).

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[in Japanese]

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