[1] Inst Nacl Ciencias Med & Nutr Salvador Zubiran, Dept Gastroenterol, Mexico City, DF, Mexico
[2] Univ Veracruzana, Med & Biol Res Inst, Digest Physiol & Gastrointestinal Motil Lab, Xalapa, Veracruz, Mexico
[3] Natl Syst Level 1 Res, Xalapa, Veracruz, Mexico
[4] Fac Med, Xalapa, Veracruz, Mexico
[5] Inst Nacl Ciencias Med & Nutr Salvador Zubiran, Dept Nutr Adm, Mexico City, DF, Mexico