1. College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, Scotland
2. Preventive Neurology Unit, Wolfson Institute of Population Health, Queen Mary University, London, UK
3. Centre for Regenerative Medicine, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh, Scotland; Anne Rowling Regenerative Neurology Clinic, University of Edinburgh, Edinburgh, Scotland
4. Anne Rowling Regenerative Neurology Clinic, University of Edinburgh, Edinburgh, Scotland; Department of Neurology, Forth Valley Royal Hospital, Labert, Scotland
5. Preventive Neurology Unit, Wolfson Institute of Population Health, Queen Mary University, London, UK; Department of Neurology, Royal London Hospital, Barts Health NHS Trust, London, UK