K Otsubo1, N Seki1, Y Nakanishi1, I Okamoto2. 1. Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan. 2. Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan. Electronic address: okamotoi@kokyu.med.kyushu-u.ac.jp.