Our main research interests have been focused on (1) phrenic nerve conduction velocity in transient phrenic nerve palsy after cardiopulmonary surgery and age-related changes; the palmar cutaneous branch of the median nerve in carpal tunnel syndrome; and transcranial magnetic stimulation study on neck flexion to detect the prognosis in Hirayama disease, (2) non-invasive respiratory care using volume-cycled ventilators in various neurological disorders including amyotrophic lateral sclerosis and multiple system atrophy, (3) pathophysiological roles of Helicobacter pyloriderived antibodies in immune-mediated peripheral (Guillain-Barre syndrome and Fisher syndrome) and central (multiple sclerosis) nerve diseases with emphasis on vacuolating cytotoxins of Helicobacter pylori and heat shock proteins, (4) functional analyses of NAD-dependent histone deacetylase SIRT in the central nervous system.