Following recent advances in medical technology, the increased number of immunocompromised patients such as those with organ transplants has led to an increase in opportunistic infections due to Nocardia. Although nocardiosis has been considered to be rare, recent reports indicate that the incidence of the infection is increasing. The Nocardia asteroides group is the principal source of infectious species, but the definition of species in Nocardia is problematic because species identification of N. asteroides has been based on mainly morphological and biochemical properties. Additionally, it was assumed that a clinical strain with properties that did not fully coincide with existing species was N. asteroides sensu lato. This caused problems in both clinical and taxonomical fields, and reclassification of N. asteroides sensu lato was necessary. Therefore, determination of the appropriate taxonomic position of N. asteroides sensu lato that is now classified as N. asteroides sensu stricto was conducted using a molecular phylogenetic method.
From 1965 to 2001, twenty-two strains of N. asteroides sensu lato were isolated from clinical samples. The phylogenetic tree using 16S rDNA sequences and detailed biochemical characters on the 22 isolates was determined. Results revealed that nine strains should be reclassified into species other than N. asteroides sensu stricto, and we proposed nine new species of the genus Nocardia. In addition, we proposed eight other new species of the genus Nocardia from other samples; hence seventeen new species were proposed in total. We also reported the first infectious cases due to Nocardia beijingensis, Nocardia transvalensis and Nocardia pseudobrasiliensis in Japan.

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This paper is a clinical study of 57 cases of infection with Trichophyton tonsurans (T. tonsurans) examined in our clinic between January 2004 and July 2006. The patients were 31 high school students, 19 junior high school students, 2 primary school students, 1 kindergartener, and 4 sports instructors. The male:female ratio was 51:6. Most patients were male Judo practitioners. Patients were clinically categorized as follows: 13 cases of tinea capitis (10 containing black dot ringworms (BDR) , 2 scaled, and 1 with inflammation) , 41 cases of tinea corporis, 1 case of tinea manum, and 7 carriers. Five patients displayed both tinea capitis and tinea corporis. Among tinea corporis patients, 21 displayed annular erythemas, whereas 19 displayed small circular eythemas characterized by a lightly inflamed non-typical rush. In 3 tinea corporis cases, we sampled T. tonsurans from hair grown inside the skin rash. Eleven of the tinea corporis patients displayed multiple lesions. Compared to patients with singular lesions, these 11 cases had a larger degree of comorbidity with BDR or HB positivity. A 6-8 week treatment with griseofulvin was efficient in 90% of the tinea capitis cases. Tinea corporis patients were healed following a 4-9 week treatment with topical antifungals and griseofulvin. When examining T. tonsurans infections, patients with BDR or lightly inflamed tinea corporis as well as asymptomatic carriers can be easily overlooked or misdiagnosed. Therefore, we suggest that mycological examination, including careful observation of the rash and KOH mount, is essential in these cases.

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We report a case of a 67-year-old woman with chromomycosis on the left upper arm. The plaque was a very small, erythematous and scaly lesion with a diameter of 1.5 cm. Fonsecaea pedrosoi was isolated as the causal fungus, and a number of Phialophora type conidia, the formation of which is considered rare, were observed. Treatment involved surgical excision of the lesion with a 5 mm margin. Follow up three years later revealed no recurrence. In Japan, 536 patients with chromomycosis were reported from 1955 to 2004. This consisted of 296 cases from 1955 to 1981 as reported by Fukushiro, and 240 cases from 1982 to 2004 as reviewed by us. Our examination of data showed that the most common causal fungi was F. pedrosoi with 137 cases (57.15%) , followed by Exophiala jeanselmei with a total of 41 cases(17.15%) , other fungal species comprised of 16 cases (6.7%) , Phialophora verrucosa in 9 cases (3.8%) and E. dermatitidis in 4 cases (1.7%) . Compared to the previous report by Fukushiro, the incidence of infection with E. jeanselmei had increased. Of the 235 cases we reported, the site of infection involved: upper extremities in 91 (38.7%) , face and neck in 42 (17.9%) , buttocks in 41 (17.4%) , lower extremities in 33 (14%) and body in 23 (9.8%) . Compared to Fukushiro' s report, cases affecting the lower extremities had decreased, whilst cases involving the buttocks had increased. Overall, the treatment for chromomycosis was either oral administration of antifungal agents, excision, thermotherapy, or a combination of these methods.

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We report a case of black dot ringworm on the right forearm caused by Trichophyton (T.) tonsurans. A 16-year-old male high school Judo-wrestler visited our clinic on September 30, 2005, complaining of a round erythematosquamous eruption with a distinct margin on the right forearm. Black dots were observed in the lesion. KOH-Parker ink prepared direct microscopy revealed abundant large endotrix arthroconidia in the hair shaft. Culture yielded yellowish-brown colonies. The isolate produced numerous round, short club-shaped microconidia along the hyphae unstained with lactophenol cotton blue (resembling matchsticks) and chlamydospores. PCR-RFLP analysis of internal transcribed spacer regions of ribosomal DNA revealed a banding pattern compatible with T. tonsurans. The lesion was cured by daily administration of 125 mg of terbinafine for 13 weeks.

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Silver has long been known to have an antimicrobial activity against bacteria and other microorganisms, and has been used as eating utensils, as dental fillings and so on. We developed a novel adduct, GX-95, of silver with nanometer-scale particles to peptidic hydrolysates from collagen. Antifungal activity of the adduct against pathogenic yeasts and filamentous fungi was examined in terms of minimal inhibitory concentrations (MICs) .
GX-95 was found to possess strong and broad antifungal activities against all fungi examined in the following MICs: 0.25 to 0.31 μg/ml for Candida albicans including resistant strains to fluconazole, itraconazole and flucytosine, 0.05 to 0.2 μg/ml for Cryptococcus neoformans strains, 0.025 to 0.4 μg/ml for Aspergillus fumigatus strains, 0.4 μg/ml for Trichophyton rubrum, and 0.05 μg/ml for Cladophialophora carrionii.

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