1. Diabetes Center, First Department of Propaedeutic Internal Medicine, Medical School, National and Kapodistrian University of Athens, Laiko General Hospital, Athens, Greece
2. Turku PET Centre, University of Turku, Turku, Finland
3. Department of Pharmacology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
4. Diabetes Centre-Diabetic Foot Clinic, Second Department of Internal Medicine, Democritus University of Thrace, Alexandroupolis, Greece
5. Department of Medicine, Tameside and Glossop Integrated Care NHS Foundation Trust, Ashton-under-Lyne, UK
6. University of Manchester, Manchester, UK
7. Manchester Metropolitan University, Manchester, UK