The opportunistic fungus C. albicans is the most important fungus in the case of oral and deep-seated infections. Adsorption, dimorphism and enzyme production are reported as pathogenic factors of C. albicans. 1,2) The yeast to hyphal transformation of C. albicans is influenced by environmental conditions, and the pathogenesis of the hyphal form is stronger than the yeast form.3) C. albicans exists in yeast form on the skin and mucous membrane and then invades the tissue in hyphal form. RAS1 is known as a signal transduction factor related to hyphal formation. 4) MAP kinase cascade and cAMP signaling pathway have been reported as the hyphal formation signal of C. albicans and is regulated by RAS1.5) The RAS-cAMP pathway requires functional EFG1, which leads to enhanced filamentous growth. 6)Mucin is the main glycoprotein of mucus and covers the inner cavities such as the trachea, stomach and intestines. Salivary mucin comprises protein, N-acetylglucosamine, Nacetylgalactosamine, galactose, fucose, mannose and Nacetylneuraminic acid.7) It is known that salivary mucin adheres to C. albicans and inhibits the adherence of C. albicans to the mucous membrane. 8) Moreover, mucin exhibits antifungal activity. 9) In this report, we demonstrate that mucin inhibits the hyphal formation of C. albicans. MATERIALS AND METHODS ReagentsMucin from bovine submaxillary glands (Sigma, U.S.A.; M4503) was used in this study.Strain and Culture Conditions C. albicans NIH A-207 yeast cells was maintained at 27°C in Sabouraud's medium (2% glucose, 1% peptone and 0.5% yeast extract) with shaking for 24 h. After the incubation, the yeast cells were washed with sterilized water, then suspended in RPMI1640 medium (Nissui Pharmaceutical Co., Ltd.). The cells were incubated without shaking at 37°C in 5% CO 2 to induce hyphal form.Effect of Mucin on the Hyphal Formation of C. albicans C. albicans NIH A-207 (1ϫ10 5 cells/ml in RPMI1640 medium) was incubated with mucin at 37°C in 5% CO 2 . After incubation, the ratio of the hyphal cells was measured. Briefly, the number of yeast cells was calculated by hemocytometer, and the total number of cells was measured by absorbance at OD 620 . The accuracy of this measurement was verified using NucleoCounter TM YC-100 (MC Techono Systems). NucleoCounter TM YC-100 can count the amount of nucleus and converted into the number of cells. When the number of hyphal cells of C. albicans was counted using this system, the resulted number was similar to the number calculated from the absorbance (data not shown). The ratio of hyphal cells was calculated using the following formula: the ratio of hyphal cellsϭ[(total number of cellsϪnumber of yeast cells)/total number of cells]ϫ100. The growth form of C. albicans cells was photographed with an IX51 microscope (Olympus Co.). Growth curves were monitored spectrophotometrically by the absorbance at OD 620 every hour until 6 h.Amount of RAS1mRNA in C. albicans C. albicans (1ϫ10 5 cells/ml in RPMI1640 medium) was incubated with mucin (1000 mg/ml) at 37°C in 5% CO 2 . Afte...

It is important to manage the residual disinfectant concentration as a countermeasure against Legionella for circulation bath. Based on the experimental data, this report examines that the differences of measuring results by absorption spectrometry which are used for determination of chlorine dioxide concentration. As a result, the simple DPD measuring device could be measured in the high precision like a spectrophotometer which went at a laboratory. Bath water however, the simple DPD measuring device could be measured in the high precision like the tap water. And it found that it was possible to use as a chlorine dioxide concentration measuring method which uses the simple DPD measuring device on fields. When measuring chlorine dioxide concentration, the influence of free residual chlorine can restrain a glycine by adding it.

Recently, the accidents caused by Legionella species have became a serious problem at public baths. To solve the problem, it is necessary to keep the residual chlorine in water at predetermined level by disinfectant. In this study, we aimed to understand the situation of chlorine disinfectant decrease in air bubble bath and ultrasonic bathtub. As the experiment conditions, we controlled to change water depth, amount of air, water temperature, volume of circulating water, gauge of air nozzle, and so on. In order to evaluate the behavior of disinfectant in water, the divergent coefficient was used to observe the decrease in the level of disinfectant over time. Regarding of the behavior of disinfectant in water in the bubble air bathtub and Whirlpool bathtub, the results were obtained respectively.

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