Cryptococcus gattii and C. neoformans are pathogenic yeasts that cause meningoencephalitis. C. gattii has four molecular types: VGI, VGII, VGIII, and VGIV. Furthermore, three genotypes have been reported for VGII, and a high pathogenicity of the VGIIa genotype has been proposed. The VGIIa strain has been isolated from a patient in Japan, but little is known about the characteristics of the polysaccharides in this strain. In this study we examined the induction of interleukin-8（IL-8）transcriptional activation and compared the nuclear magnetic resonance（NMR）spectra of extracellular polymeric substances（EPSs）, mainly polysaccharides, from the VGIIa, VGIIb, and VGIIc genotypes. The induction of IL-8 by C. gattii EPSs was weaker than that by C. neoformans EPSs. The anomeric proton signals in the NMR spectra of EPSs obtained from VGII isolates were similar, and the polysaccharides were mainly mannose, xylose, galactose, and glucuronic acid. These results suggest that the extracellular polysaccharides from the VGIIa strain isolated in Japan are almost the same as those from other VGII strains.

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Background: Dermatophytosis usually causes a skin problem, which requires both clinical findings and laboratory investigations for diagnosis. Whereas, fungal culture is considered as the gold standard procedure, it is more difficult to perform compared to potassium hydroxide（KOH）examination. Objective: To evaluate the efficacy of KOH and fungal culture examinations from skin-scraping specimens, which were kept in transparent adhesive tapes at different time intervals. Methods: Skin-scraping specimens were collected from clinically suspected cases by conventional technique using scalpel blades and kept using transparent adhesive tapes. KOH（10%）preparation and fungal cultures were then performed by highly experienced technicians at different time intervals: day 0（the day of specimen collection, which was set as the standard reference point）, day 3 or 4, day 7, day 14, and day 28. Thereafter, the yield for detection of fungal elements by KOH examination and positive fungal cultures from specimens stored in adhesive tape was determined at different time intervals and compared to the results from the standard reference point. Results: The sensitivity of KOH exami-nations from 162 patients at different time intervals showed no significant difference when compared to the standard reference point at day 0. In contrast, the sensitivity of fungal culture progressively decreased as the storage period was prolonged. Conclusions: KOH examination of skin-scrapings from the adhesive tape storage technique yield good results even when specimens have been kept up to one month. On the other hand, the sensitivity of fungal cultures gradually declines as storage time is extended.

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　The minimum inhibitory concentration (MIC) and the minimum fungicidal concentration (MFC) of luliconazole against Trichophyton rubrum (14 strains) and Trichophyton mentagrophytes (14 strains), which are the most common cause of tinea, were compared with those of 6 topical antifungal drugs of lanoconazole, bifonazole, efinaconazole, liranaftate, naftifine and terbinafine.
　Luliconazole showed the most potent antifungal activity (MIC₉₀ =0.00098 μg/ml and MFC₉₀ =0.0078 μg/ml) among the compounds tested against the two species. Efinaconazole and bifonazole, the drug of azole-class, showed a large MFC/MIC ratio. On the other hand, these ratios of luliconazole and lanoconazole were as small as those of liranaftate, naftifine and terbinafine which are thought to possess fungicidal mechanism. These results suggest that luliconazole possesses fungicidal activity against both species of Trichophyton.
　In this study, we found that luliconazole had the most potent antifungal activity among the major topical antimycotics used in Japan and the US. Luliconazole would be the best-in-class drug for dermatophytosis in clinics.

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　Luliconazole (LLCZ), an imidazole derivative with a broad spectrum of potent antifungal activity especially for T. rubrum and T. mentagrophytes, is under development as a new drug for treatment of tinea unguium.
　It is well known that curative effect of an antifungal agent in dermatophytosis is affected by the pharmacokinetics of an agent at the infection loci as well as its antifungal activity, but there is no report about the affinity of LLCZ to nail keratin. We studied LLCZ affinity to keratin powder prepared from healthy human nail and porcine hoof. The LLCZ adsorbed to keratin preparations was washed with phosphate buffer, and its concentration in the buffer supernatant was measured by HPLC. Antifungal titer of the supernatant was also biologically confirmed by disk diffusion assay. Adsorption rate of LLCZ was 80% or more, and LLCZ was gradually liberated into washing buffer. Cumulative liberation rate in 10 times repeated washing against initially adsorbed drug amount was 47.4% for keratin from human nail and was either 52.5% or 50.8% (depending on the LLCZ concentration) for keratin from porcine hoof. The supernatant showed antifungal potential to T. rubrum. These results indicate that LLCZ applied to the nail surface is fully adsorbed to nail keratin and gradually liberated from it. The nail keratin could function as drug reservoir to supply biologically active LLCZ to the nail tissue region of infection loci. The LLCZ delivered to the loci would exert its antifungal potential on tinea unguium. This study also suggests the versatility of porcine hoof powder as an alternative to human nail keratin preparation for non-clinical study.

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　We evaluated luliconazole nail solution, originally generated formulation, for the topical treatment of onychomycosis by two infection models. First, a suspension of Trichophyton mentagrophytes was dropped onto the ventral layer of human nail plate and these nails were set in Franz diffusion cells. After 9-day culture, luliconazole nail solutions (1, 3, and 5%) were applied to the dorsal surface of the nails once a day for 7 days. After application, fungal viability was assessed by measuring the ATP contents of the samples. The dose-dependent efficacy was confirmed, with 3% and 5% luliconazole nail solutions producing significantly lower ATP levels at 7-day treatment. When 3% and 5% luliconazole nail solutions were evaluated in a rabbit model of onychomycosis, both concentrations completely inhibited the recovery of fungi on culture after 4-week treatment. We therefore think these results indicate that 5% luliconazole nail solution is sufficiently potent for treatment of onychomycosis.

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　To clarify the character of luliconazole nail solution we have developed, we investigated luliconazole distribution and antifungal activity in nail plate. An in vitro permeation study which measured luliconazole concentration of sliced nail in the transverse direction after treatment of luliconazole nail solution was conducted to investigate for concentration dependency and the influences of nail thickness and treatment duration. When 0.2, 1, 3, 5, and 7.5% luliconazole nail solutions were used, luliconazole was detected in the all the layers of nail and there was a concentration gradient from the dorsal side to deep nail layers. The luliconazole concentration was almost same after 14-day treatment with 5% luliconazole nail solution when using nails of different thicknesses. And we confirmed that concentration of luliconazole into the nail was increased depending on the treatment duration. In zone of inhibition test after 14-day treatment, 5% luliconazole nail solution showed statistically high formation rate of zones of inhibition compared to 8% ciclopirox nail lacquer. Above all, these data suggested that 5% luliconazole nail solution has the potential to show high therapeutic effect for onychomycosis.

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　Cryptococcus neoformans and Cryptococcus gattii are fungal pathogens that cause diseases in humans. Cryptococcal species mainly enter the body by inhalation and in most cases are eliminated by host defense mechanisms. Some cases, however, progress to pneumonia and subsequent dissemination of the infection to the central nervous system (CNS), leading to meningoencephalitis. Cryptococcus can cross the blood-brain barrier transcellularly, paracellularly and through infected phagocytes (the Trojan horse mechanism). The reason for the tropism of Cryptococcus to the CNS could be partially explained by the abundance of inositol in the brain, which causes the hyaluronic acid in fungal cells to bind to host CD44 receptors. There are differences in the clinical characteristics of C. neoformans and C. gattii. HIV infection is the most common risk factor for cryptococcosis due to C. neoformans, whereas C. gattii infection with CNS involvement is frequently found in otherwise healthy individuals exposed to plant propagules found in tropical and subtropical regions. As the virulence traits of C. neoformans contributing to CNS disease, high macrophage uptake and laccase activity are associated with the fungal burden and the rate of clearance of the infection from the brain. Recent reports suggested that the C. gattii VGII strain suppresses host immune responses in the lung and causes more lung infections than CNS diseases. Furthermore, the anti-GM-CSF autoantibodies are a risk factor for CNS infection by the C. gattii VGI strain. To understand the mechanism by which Cryptococcus causes CNS disease, it is important to consider the specific characteristics of the species and the molecular types.

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