Cryptococcus neoformans is an opportunistic human pathogen belonging to basidiomycetous fungi and has unique properties in cell cycle progression. The purpose of this study was to measure the duration of the cell cycle in this yeast. Under standard liquid culture conditions (1% yeast extract, 1% polypeptone, and 1% glucose; 24°C; and 150 rpm), the doubling time of exponentially growing C. neoformans was 132 ± 16 min (mean ± standard deviation), and the durations of the G1, S, G2, and M phases were about 71, 18, 25, and 18 min, respectively. DNA synthesis started before bud emergence, and finished by the time the size of the bud became 1/4 that of the mother cell. The doubling time of the daughter cells was about twice that of the mother cells. The spindle pole body was located on the outer nuclear envelope and showed a duplicated form from the G1 phase to the G2 phase. These data form a basis for further cell cycle study of C. neoformans.

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Over the 2 year period from October, 1997 to September, 2005, the clinical efficacy of 125 mg/day of terbinafine was evaluated in 356 patients with onychomycosis. Of these, 253 patients were followed up for 6 months after oral treatment of terbinafine, 120 for 1 year, and 56 for 2 years. The improvement ratio increased depending on follow-up period: 30.4% in 6 months, 65.0% in 1 year, and 67.9% in 2 years. However, in 25 patients who showed regression from onychomycosis at the 1 year period, 8 patients (32.0%) relapsed.
The muddy rate of the first toenail was decreased from pre-treatment with terbinafine in 92.1% at 6 months, 91.7% at 1 year and 87.5% at 2 years. It is considered that efficacy of this medication is maintained within 1 year after the treatment, but the number of patients who experience a relapse is likely to increase from 1 year to 2 years.

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Quorum sensing through farnesol, a quorum sensing molecule, regulates virulence and morphogenesis in Candida albicans. Farnesol and high cell density of C. albicans repress hyphal formation in a minimal medium containing N-acetyl-D-glucosamine. Global transcription profiling at an early stage of quorum sensing by C. albicans in the N-acetyl-D-glucosamine medium was analyzed. Twenty-two of a total of 53 genes responded to both farnesol and high cell density. From in silico analysis and previous published data, nine of these genes including those encoding amino acid biosynthesis were controlled by the Gcn4p regulator. Nine other genes which included genes encoding central carbon metabolism were controlled by negative regulators including Nrg1p, Tup1p, Ssn6p, and/or Mig1p. Other genes not controlled by these regulators included genes related to oxidative stress, glucose metabolism, and agglutination. Expression of genes related to amino acid biosynthesis and central carbon metabolism in this study is similar to a previous report of transcription profiling in C. albicans following its internalization by phagocyte cells and adaptation to host challenges.

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Yeasts of 17 processed fresh edible (raw) sea urchins obtained from seven countries were analyzed. In total, 45 to 7×10⁴ colony-forming units (CFU) /g of sea urchins were recovered, and 23 yeast species were identified. Of these species, six pathogenic yeasts (Candida albicans, C. sake, Debaryomyces hansenii, Pichia anomala, Rhodotorula mucilaginosa, and Trichosporon mucoides ) were detected from 11 sea urchins (65%) . As these yeasts are opportunistic pathogens, infections in healthy individuals normally will not occur, but it should be understood that processed fresh edible sea urchin includes such opportunistic yeast pathogens.

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A PCR primer specific to Nocardia farcinica was prepared based on sequence information of random amplified polymorphic DNA (RAPD) analysis. The PCR primer amplifies N. farcinica species only; no amplification was observed in 25 other Nocardia strains that we tested. Specificity of the primer for N. farcinica was also confirmed using other fungal and bacterial strains that are frequently isolated from clinical samples such as sputa and broncho alveolar lavage (VAL) .

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