ABSTRACT
BACKGROUND: Various pancreatic enzyme preparations are used for the treatment of pancreatic insufficiency but their bioequivalence is often unknown. AIM: To determine in vitro the pH-dependent release and acid resistance of enzymes from three commercially available pancreatin capsules, two containing enteric-coated (Creon 25000; Eurobiol 25000) and one uncoated (Eurobiol 12500) microspheres. METHODS: Dissolution experiments were performed at pH values ranging from 4.0 to 5.8. Lipase, chymotrypsin and amylase activities were measured in the solution as a function of time. RESULTS: Eurobiol 25000 started to release its enzymes significantly at pH 5.0 (t(1/2) = 71 min), whereas the enzymes from Creon 25000 were only released at higher pH value (5.4; t(1/2) = 49.2 min). Unlike chymotrypsin, lipase and amylase were highly sensitive to acidic conditions at the lowest pH values tested. Both enzymes were also found to be sensitive to proteolytic inactivation at the highest pH values tested. Overall, Eurobiol 25000 released higher amounts of active amylase and lipase than Creon 25000 at the pH values usually found in duodenal contents. The uncoated Eurobiol 12500 preparation was, however, the only one that could immediately release rather high levels of active chymotrypsin and lipase at low pH (4.5). CONCLUSION: These findings suggest that pH-sensitive enteric-coated pancreatin products containing similar amounts of enzymes might not be bioequivalent depending on the pH of duodenal contents.
Subject(s)
Gastrointestinal Agents/pharmacokinetics , Pancreatic Extracts/pharmacokinetics , Pancrelipase/pharmacokinetics , Amylases/analysis , Animals , Biological Availability , Chymotrypsin/analysis , Duodenum/metabolism , Exocrine Pancreatic Insufficiency/drug therapy , Exocrine Pancreatic Insufficiency/metabolism , Humans , Hydrogen-Ion Concentration , Lipase/analysis , Microspheres , Solubility , Tablets, Enteric-CoatedABSTRACT
We report a clinicopathologic study in sixteen patients (11 male and five female) with thymomas. The fairly large proportion of children (3 cases: 12.5%) and significant number of advanced forms may at least partly explain the low survival rate (27% at five years) in our series. Advances in histologic studies of tumors have made possible the accurate diagnosis of thymomas, but the value of a histologic classification is still under debate. Conversely, pathologic and surgical classification is at present the best predictor of outcome.
