1. Department of Radiation Protection, National Atomic Research Institute, Taoyuan 325, Taiwan
2. Division of Behavioral Neurology, Department of Neurology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan
3. Institute of Gerontology, National Cheng Kung University, Tainan 701, Taiwan
4. Alzheimer’s Disease Research Center, National Cheng Kung University Hospital, Tainan 704, Taiwan
5. Department of Neurology, Show Chwan Memorial Hospital, Changhua 500, Taiwan
6. Department of Neurology, Institute of Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung 833, Taiwan
7. Department of Nuclear Medicine, Chang Bing Show Chwan Memorial Hospital, Changhua 505, Taiwan
8. Healthy Aging Research Center and Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan
9. Molecular Imaging Center and Department of Nuclear Medicine, Chang Gung University and Chang Gung Memorial Hospital, Taoyuan 333, Taiwan