Adult male BALB/c mice (4-5 weeks of age) were obtained from Oriental Bioservice (Tokyo). The initial mean body weight of the mice was 22.1±0.2 g (±standard error). The mice were acclimated for one week in a housing facility and maintained on commercial rodent chow ad libitum at 21°C with a 12- hr light/dark cycle before treatment. The mice were randomly assigned to a treatment group (six per group) and housed in polycarbonate cages. The food and water consumption per group as well as the body weight of each mouse were monitored daily. The care and treatment of mice were in accordance with the guidelines established by Fukushima Medical University’s Institutional Animal Care and were approved by the Use Committee.