[1] Univ Malaysia Sarawak, Fac Med & Hlth Sci, Jalan Datuk Mohammad Musa, Kota Samarahan 94300, Sarawak, Malaysia
[2] Sarawak Gen Hosp, NIH, Inst Clin Res, Clin Res Ctr, Jalan Hosp, Kuching 93586, Sarawak, Malaysia
[3] Natl Univ Singapore, Yong Loo Lin Sch Med, 21 Lower Kent Ridge Rd, Singapore 119077, Singapore
[4] Nanyang Technol Univ, Sch Biol Sci, 50 Nanyang Ave, Singapore 639798, Singapore
[5] Sarawak Gen Hosp, Minist Hlth, Neurol Dept, Jalan Hosp, Kuching 93586, Sarawak, Malaysia
[6] Sibu Gen Hosp, Neurol Dept, Minist Hlth, KM 5-1-2 Jalan Ulu Oya, Sibu 96000, Sarawak, Malaysia