We made a molecular epidemiological study of Arthroderma benhamiae, a teleomorphic species of the Trichophyton mentagrophytes complex, using polymorphisms of the non-transcribed spacer region (NTS) of ribosomal DNA. Thirteen isolates - Hyogo 2 isolates, Saitama 2 isolates, Shimane 2 isolates, Tokyo 1 isolate, Nagasaki 4 isolates - were isolated from dermatophytosis lesions on pet animals and/or their owners, while 2 Gifu isolates were cultured from lesions on the face and hand of a pet shop worker. Along with the thirteen isolates, four tester strains for a mating study from Belgium were extracted total DNA and restriction fragment length polymorphisms (RFLP) of NTS were detected by a hybridization technique. The thirteen isolates were divided into 6 DNA types but none of them showed the same profile as the strains from Belgium. The most prevalent DNA type was composed of 7 isolates, from Saitama (1 isolate), Shimane (2 isolates) and Nagasaki (4 isolates) in 1996-2001. These isolates were considered to be a clone and spread by the transportation of pet animals. Since the species was not found in an intensive mating study carried out in 1980, several different clones of A. benhamiae may have been transported into Japan after that time.

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A 65-year-old man had tetraplegia caused by a cervical spinal cord injury, and could only lie in bed with a respirator. On the 14 th day of hospitalization, a rash developed on his back. The eruption grew rapidly, and became a giant erythematous plaque with ulcer, pustules, and red papules. Direct KOH examination showed branching Aspergillus hyphae. A slide culture showed sub globose shaped vesicles with phialides. Based on these findings, the case was diagnosed as primary pyoderma-like aspergillosis caused by Aspergillus fumigatus. He was treated with bifonazole and sulfadiazine silver, and one month later no Aspergillus hyphae were observed either by direct KOH examination or by culture. The patient died about 2 months later, however, because of aggravation of his general condition. Careful observation is necessary for compromised or unmoving patients with pyoderma-like aspergillosis.

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Two strains of Histoplasma capsulatum var. capsulatum were isolated in Japan : one from a Thai AIDS patient and the other from a Chinese non-immunocompromised patient. The phylogenetical relationship among the two isolates and reference strains of H. capsulatum from other geographical populations was investigated. Random amplified polymorphic DNA (RAPD) analysis of the two H. capsulatum strains showed that they had RAPD band patterns similar to those of the reference Thai isolates and North American strains, although the patterns differed slightly from those of the reference strains. Phylogeny of thirty geographically diverse H, capsulatum isolates representing the three varieties, var. capsulatum, var. duboisii and var. farciminosum were evaluated using nucleotide sequences of the internal transcribed spacer (ITS) region (ITS 1-5.8S rDNA -ITS2). We found that the ITS region contained sufficient information to resolve the phylogenetic relationship among the fungal isolates. An unrooted dendrogram constructed from the ITS sequences showed that thirty strains of H. capsulatum could be classified into eight geographic clades; Asia type (i), South America types A (ii) and B (iii), North American types 1 (iv) and 2 (v), H. duboisii types A (vi) and B (vii), and East Asia type (viii). Based on the ITS region sequence analysis, the two strains isolated from the Thai and Chinese patients in Japan were found to be distinct from Asia type (i) in which eight Thai, one Chinese, one English and one Indonesian isolate were included. Some extent of DNA polymorphism was observed between the North America type 1 isolates and the Thai and Chinese strains isolated in Japan. We believe that the Thai and Chinese isolates were unique and propose a new Glade, East Asia type (viii) for the two strains. DNA sequence analysis of the ITS region provided useful information to understand the epidemiology and evolution of H, capsulatum.

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Kimitsu Chuo Hospital is located in the middle of Chiba Prefecture along Tokyo Bay. An epidemiological survey of dermatophytosis was made at the dermatology clinic of the hospital from January 1994 through December 1999. Dermatophytosis patients numbered 2, 580 and disease types were composed of : tinea pedis 1, 656 (64.2%), tinea unguium 377 (14.6%), tinea corporis 308 (11.9%), tinea cruris 139 (5.4%), tinea manuum 92 (3.6%), tinea capitis 6 (0.2%) and tinea profunda 2 (0.1 %). Species frequencies in the 1, 610 strains isolated from these patients were as follows : 929 (57.7%) of Trichophyton rubrum, 651 (40.4%) of T. mentagrophytes, 9 (0.6 %) of Microsporum gypseum, 8 (0.5 %) of M. canis, 8 (0.5 %) of Epidermophyton floccosum and 5 (0.3 %) of T. aiolaceum. The ratio of T.R/T.M was 1.43 in all the isolates, and 0.81 in the isolates from tinea pedis. These ratios were lower than those of the epidemiological survey of dermatomycoses in Japan in 1997. T. mentagrophytes was characteristically dominant in this hospital and resulted from a drastic increase in tinea pedis caused by this species in the summer season.

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Paracoccidioidomycosis (PCM) is a deep mycosis caused by the thermo-dependent dimorphic fungus Paracoccidioides brasiliensis and is prevalent in Latin American countries. Diagnosis of PCM is sometimes difficult outside the endemic countries, thus a rapid and conclusive method for diagnosis of PCM has been anticipated. We compared the sensitivities of a nested PCR method for detecting the gp43 gene and a commercial kit for detecting (1 3) -j9-D-glucan in the blood of experimentally infected mice. Blood samples were collected from mice at 0 (soon after inoculation), 6, 12, 24, 48, and 72 hours and 5, 7, 10, 14, 17, 21, 24, 28 and 56 days after the intravenous inoculation of 106 yeast cells of P. brasiliensis, and were separated into clots and plasma. The (1→3) -β-D-glucan detection kit in the plasma showed positive reactions in some samples within 7 days and 28 and 56 days after infections. In contrast, the PCR method was more sensitive than the (1→3) -β-D-glucan detection kit throughout the observation period. The clot samples yielded more sensitive PCR-results than did the plasma samples. Although 24 hours is required for the PCR detection, it was confirmed to provide an accurate diagnosis of PCM.

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Aspergillus fumigatus causes serious, life-threatening human infection, and is one of the most important pathogenic fungi. Little is known, however, about its mechanism of infection or its virulence factors.
To learn about its virulence factors, the effect of the culture filtrate of A. fumigatus on macrophages was studied. When cocultured with A. fumigatus in 96-well microplates, murine peritoneal macrophages showed significant morphological changes indicating serious cellular damage, even when the macrophages were not in direct contact with the fungus. Then culture filtrates of Aspergillus spp., A, fumigatus, A. lavus, A. terreus and A. niger, were prepared by culturing the fungus in 96-well or 24-well microplates for 24 h, and the effect of the culture filtrates was determined by culturing macrophages with or without culture filtrate. When cultured with the culture filtrate of A. fumigatus at a concentration of 1 % or higher, macrophages demonstrated significant morphological changes, leading to their death. Treatment with heat greatly lowered the activity of the culture filtrate. In contrast, culture filtrates of A. terreus and A, flavus showed no detectable effect on macrophages, whereas A. niger did display a similar, but much weaker effect.
Our study strongly suggests that A. fumigatus releases a toxic product (s) in the medium very rapidly, and this may be critically involved as the virulence factor in human infection, at least in part, by causing serious injury to macrophages.

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