To determine the pathophysiology of the fungal infection and defense mechanisms against superficial dermatomycosis, two series of experimental infections of Trychophyton mentagrophytes were made on the forearm of a male volunteer. One series was applied topical steroid ointment, the other the vehicle alone. The infected sites were biopsied from each row weekly up to the 4^th week, and the set of sites were studied and compared clinicallly, histopathologically and immunohistochemically. For the study against subcutaneous fungal infection, the same experiments were studied using the subcutaneous inoculation of Sporothrix schenckii.
The pathophysiology of the superfical dermatophytosis was thought to be the same as those of the contact (allergic) dermatitis, including the physiodynamics of CD-1 cells. The principal mechanism of the defense lay in the removal of the foreign materials (fungi) together with keratinocytes whose turnover increased because of the eczematous reaction. It was proved that the topical application of steroid ointment suppressed the immune reactions locally, thus forming a paradoxical feature with little inflammatory reaction and abundant fungal elements (so-called atypical tinea).
The pathophysiology of the subcutaneous fungal infection was thought to be a suppurative granulomatous reaction and pathologically showed a mixed cell granuloma. The neutrophils and macrophages engulfed and digested the fungi in the forefront, but the circumference was surrounded by epithelioid cells and/or foreign body granuloma. Transepithelial elimination also played some role in the defense. It was proved that when the defense mechanism was weakened by the topically applied steroid ointment, not only the clinical symptoms but also the fungicidal tissue reaction were subdued, and histocytes only engulfed fungi to protect them from dispersion.
The trichophytin reaction turned positive on the 14^th day, and the sporotrichin reaction on the 7^th day.

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From the second half of the 1990s, an increased regard has been given to the fungal spoilage of foods as follows: 1) post-harvest diseases and losses of fruits and vegetables, 2) deterioration of low water activity foods by xerophilic fungi, 3) contamination of psychrotolerant or psychrophilic fungi on foodstuffs and processed foods during storage and distribution at low temperature, and 4) spoilage of heat processed foods and soft drinks by heat-resistant fungi.
In accordance with an international concern about food safety, mycotoxin contamination of foods has gained much global attention in recent times owing to its potential health hazards. The evaluation of mycotoxin hazards is principally based on the determination of a no-observed effect level (NOEL) in long-term toxicological studies, and the application of a safety factor (usually 100). In addition to hazard assessment, data on the natural occurrence of mycotoxins in various commodities and food intake data are needed to enable exposure assessment. Thus risk assessment of mycotoxins is, in fact, the product of hazard assessment and exposure assessment.
In 1997, the FAO/WHO Joint Expert Committee on Food Additives (JECFA) considered estimates of the carcinogenic potency of aflatoxins and the potential risks associated with their intake. Recently the Codex Alimentarius Commission (Codex) has established standards for aflatoxin M₁ in milk and for patulin in apple juice. The Codex is an international organization, supported by FAO/WHO, aiming at facilitating world trade and protecting the health of the consumer by developing international standards for food and feeds.
Apart from aflatoxins, the JECFA has measured a provisional tolerable daily intake (TDI) for ochratoxin A, patulin, deoxynivalenol, T-2/HT-2 toxins, zearalenone and fumonisins.
In 2001, the mycotoxins evaluated or re-evaluated at the JECFA meeting included ochratoxin A, deoxynivalenol, T-2/HT-2 toxins, fumonisins, and aflatoxin M₁. In Japan, specific regulations now exist for deoxynivalenol (1.1ppm) in wheat grains and for patulin (50ppb) in apple juice and its products.

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Imported mycoses in Japan, particularly coccidioidomycosis and histoplasmosis, have been on the increase in the past 15 years, and more than 40 patients have been reported to suffer from each of these diseases. In spite of their high infectivity and virulence, imported mycoses have received little attention by physicians. Concerning coccidioidomycosis, in particular, physicians should keep abreast of updated and detailed information, and should maintain close contact with clinical microbiologists. In this review, the general profile of coccidioidomycosis, including its diagnosis and treatment, was described, and the importance of these diseases as well as their recent trends were discussed.

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Two actinomycete strains that were isolated from patients in Japan were assigned provisionally to the genus Nocardia based on their morphological characteristics. The two isolates were further studied to determine their specific taxonomic status. Detailed chemotaxonomic characterization and 16S rDNA sequence data for the strains showed that they are most similar to Nocardia vinacea. DNA-DNA hybridization experiments indicated that strain IFM 0344 should be identified as N. vinacea, and that strain IFM 0323^T is classifiable as a new species. This report describes the first isolation of N. vinacea from clinical samples. A new species of the genus Nocardia is proposed based on their phenotypic and phylogenetic characteristics: Nocardia anaemiae for IFM 0323^T (=NBRC 100462^T=JCM 12396^T=DSM 44821^T).

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We examined the effect of a clove (Syzygium aromaticum) administered by two different routes on Candida albicans growth, using a murine oral candidiasis model. When the clove preparation was administered into the oral cavity of Candida-infected mice, their oral symptoms were improved and the number of viable Candida cells in the cavity was reduced. In contrast, when the clove preparation was administered intragastrically, oral symptoms were not improved, but viable cell numbers of Candida in the stomach and feces were decreased. These findings demonstrate that oral intake of an herbal food, clove, may suppress the overgrowth of C. albicans in the alimentary tract including the oral cavity.

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We have developed degenerated primers for the isolation of several fungal species catalases, based on the known catalase genes of several yeast species. Using a combination of degenerated primers and the nested polymerase chain reaction (PCR) method, we were able to obtain PCR products from Candida dubliniensis, C. tropicalis, and C. glabrata. The nucleotide sequence of the PCR products amplified showed that those fragments contained sequences homologous with the known Candida catalases, indicating the usefulness of the designed primers. We determined the nucleotide sequences of the open reading frames and respective 5' untranscribed regions of these yeasts and compared each sequence with that of the respective related species. The difference between the deduced amino acid sequence of catalase of C. dubliniensis and C. albicans was 5 in 485 amino acids. The nucleotide sequence of C. glabrata catalase was identical to the sequence results from the genome sequence project which was recently released, whereas that of the catalase of the C. tropicalis clinical isolate was not the same as the strain Pk233, n-alkane-utilizing C. tropicalis.
The catalase activities of all the strains tested so far were activated by short-term hydrogen peroxide treatment, suggesting that common mechanisms were involved in the induction of catalase activity, although the nucleotide sequences of the 5' untranscribed region of these yeasts were diversified.

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