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Abstract.: Cytochrome P450 (CYP) catalyzes the oxidation of many endogenous and xenobiotic compounds. The expression of CYP isozymes are modulated by endogenous hormones and xenobiotics. We found that, although CYP2C11 and CYP3A2 are adult male-specific isozymes, they are also expressed in prepubertal female Sprague Dawley (SD) rats. However, the mRNA levels for these isozymes in prepubertal female SD rats decreased over time and became undetectable at 7 weeks of age. On the other hand, ovariectomy, administration of ICI182780, a specific estrogen antagonist, or administration of lindane, which is a widely used pesticide with anti-estrogenic effects, induced these adult male-specific CYP mRNAs in adult female SD rats. These results suggest that estrogen is involved in suppression of both CYP2C11 and CYP3A2 in adult female rats. The expression of these CYP isozymes in female rats, therefore, is affected by sexual maturity and by disrupting adult female hormonal homeostasis. We also performed a field survey to examine whether the induction of CYP2C11 or CYP3A2 differs between adult female roof rats in rural and metropolitan districts. RT-PCR showed that the mRNAs for CYP2C11 and CYP3A2 were expressed in half of the adult female roof rats captured in Osaka (as a metropolitan area district) but not in those captured in Hokkaido (as a rural district). Thus, induction of the adult male-specific CYP isozymes in adult female roof rats captured in Osaka might be caused by consumption of xenobiotics with anti-estrogenic effects. Keywords:: cytochrome P450 (CYP), CYP isozyme, biomarker, adult male-specific CYP, estrogen antagonist

Although the antioxidant properties of green, oolong, and black teas have been well studied, antioxidant activity has not been examined in roasted tea. Therefore, in the current studies, we investigated the antioxidant activity of roasted tea in comparison with those of green, oolong, and black teas. Using water extracts of the various teas, we examined the total phenolic content as well as the antioxidant activities, including the reducing power, the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, and the inhibition of hemolysis caused by 2,2'-azo-bis(2-amidinopropane) dihydrochloride (AAPH)-induced lipid oxidation in erythrocyte membranes. The roasted tea contained lower levels of total phenolics than green, oolong, or black tea (green tea > oolong tea > black tea > roasted tea). The relative reducing power and DPPH scavenging activity decreased in the following order: green tea > roasted tea > oolong tea > black tea. Also, green tea was more effective against AAPH-induced erythrocyte hemolysis than other teas (green tea > roasted tea = oolong tea = black tea). These results suggest that roasted tea is beneficial to health, in humans, because of its high antioxidant activity. Keywords: Antioxidant activity, roasted tea, phenolic content

Intercolony drifting of the Japanese paper wasp, Polistes rothneyi Cameron, was observed using individual color marking of workers. No genetic relatedness was found by using microsatellite markers between drifting workers and the recipient colony. Genetic analysis of brood in the recipient colony revealed reproduction by non‐kin drifting worker(s) in the queenless host colony. The non‐kin broods were raised like broods of the recipient colony until the genetic analysis. This study is the first evidence of male production by non‐kin workers in temperate eusocial wasps. This natural event would compensate for fitness loss as an alternative reproductive strategy evolved under predation and climatic pressures, and is also discussed from the viewpoint of mutual help. [ABSTRACT FROM AUTHOR]