[1] Univ Tsukuba, Fac Med, Dept Neurosurg, 1-1-1 Tennodai, Tsukuba, Ibaraki 3058575, Japan
[2] Univ Tsukuba, Grad Sch Comprehens Human Sci, 1-1-1 Tennodai, Tsukuba, Ibaraki 3058575, Japan
[3] Ibaraki Prefectural Univ Hlth Sci, 4669-2 Ami, Inashiki, Ibaraki 3000331, Japan
[4] Fukuyama Univ, Dept Pharmaceut Sci, 1 Sanzo,Gakuen Cho, Fukuyama, Hiroshima 7290292, Japan