1. Department of Cellular & Molecular Medicine, University of Bristol, School of Medical Sciences, University Walk, Clifton, Bristol BS8 1TD, UK
2. Department of General Thoracic Surgery, Hospital Clinic, c Villaroel 170, E-08036 Barcelona, Spain
3. Ethics Institute, Dublin City University, Glasnevin, Dublin 9, Ireland
4. Laryngeal Research Group, UCL Ear Institute, University College London and the Royal National Throat Nose and Ear Hospital, 332 Gray’s Inn Road, London WC2A 8EE, UK.