[1] Dongduk Womens Univ, Coll Pharm, Seoul, South Korea
[2] Seoul Natl Univ, Dept Chem, Seoul, South Korea
[3] Seoul Natl Univ, Dept Neurosurg, Coll Med, Seoul, South Korea
[4] Seoul Natl Univ Hosp, Clin Res Inst, Seoul, South Korea
[5] Seoul Natl Univ, Boramae Med Ctr, Dept Neurosurg, 20 Boramae Ro 5 Gil, Seoul 07061, South Korea