1. a NMR Research Unit, Department of Biochemistry and Center for Neurosciences and Cell Biology , University of Coimbra , Coimbra, Portugal
2. b Department of Chemistry , University of Coimbra , Coimbra, Portugal
3. c Pediatrics Hospital of Coimbra , Coimbra, Portugal
4. d Department of Endocrinology , University Hospital of Coimbra , Coimbra, Portugal