1. Division of Gastroenterology, Escola Paulista de Medicina, Federal University of Sao Paulo, Sao Paulo, Brazil.
2. Division of Biomedicine, University of Central Florida, Orlando, Florida, USA.
3. Division of Medicine, Escola Paulista de Medicina, Federal University of Sao Paulo, Sao Paulo, Brazil.
4. Division of Psychiatry and Psychology, School of Medicine, University of Sao Paulo, Sao Paulo, Brazil.