[1] Nippon Kayaku Co Ltd, Pharmaceut Grp, R&D Div, Evaluat Grp,Biol Dept,Kita Ku, Tokyo 1158588, Japan
[2] Toyama Med & Pharmaceut Univ, Inst Nat Med, Dept Biosci, Div Pathogen Biochem, Toyama 9300194, Japan
[3] Toyama Med & Pharmaceut Univ, Century COE Program 21, Toyama 9300194, Japan