1. Department of Otolaryngology, University of California San Diego, La Jolla, California, USA;
2. Department of Medicine, Division of Gastroenterology and Hepatology, University of California San Diego, La Jolla, California, USA;
3. Department of Biostatistics and Informatics, Colorado School of Public Health, University of Colorado-Anschutz Medical Campus, Aurora, Colorado, USA;
4. The Rome Foundation Research Institute, Chapel Hill, North Carolina, USA.