1. Clinical Ageing Research Unit Newcastle University Newcastle upon Tyne United Kingdom
2. Department of Clinical and Experimental Medicine University of Pisa Pisa Italy
3. Positron Emission Tomography Centre Newcastle University Newcastle upon Tyne United Kingdom
4. Neurodegenerative Diseases Center Azienda Ospedaliero Universitaria Pisana Pisa Italy
5. Department of Neurology and Laboratory of Neuroscience Istituto Auxologico Italiano IRCCS Milan Italy
6. Department of Pathophysiology and Transplantation, Dino Ferrari Center Università degli Studi di Milano Milan Italy
7. Department of Nuclear Medicine and PET Centre Aarhus University Hospital Aarhus Denmark