1 Department of Clinical Medicine and Surgery, Section of Respiratory Diseases, University Federico II, Azienda Ospedaliera dei Colli-Monaldi Hospital, Naples, Italy.
2 Department of Translational Medical Science, "Federico II" University of Naples, Italy.
3 NuvoAir U.S. Inc, Boston, Massachusetts, USA.
4 Cystic Fibrosis Center, Azienda Ospedaliero Universitaria Integrata di Verona, Verona, Italy.