[1] Showa Inan Gen Hosp, Digest Dis Ctr, 3230 Akaho, Komagane 3994117, Japan
[2] Univ Tsukuba Hosp, Dept Pediat, Tsukuba, Ibaraki, Japan
[3] Shinshu Univ Hosp, Dept Gastroenterol, Matsumoto, Nagano, Japan
[4] Shinshu Univ, Int Relat Off, Sch Med, Matsumoto, Nagano, Japan
[5] Baylor Coll Med, Dept Med, Houston, TX 77030 USA