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The aim of this study was to estimate the benchmark dose (BMD) for pancreas dysfunction caused by cadmium (Cd) exposure in smelters. Smelter workers who had been exposed to Cd for more than 1 year and matching nonoccupationally exposed subjects were asked to participate in this study. Urinary cadmium (UCd) was used as a biomarker for exposure, serum insulin and amylase were used as biomarkers for pancreatic effects. In this study, serum insulin and amylase were lower in the smelter workers than in the nonoccupationally exposed subjects. A significant dose-response relationship with UCd was displayed. BMDs in terms of urinary Cd corrected for creatinine were calculated by use of BMDS (version 1.3.2). The benchmark dose lower limit of a one-sided 95% confidence interval (BMDL) for 10% excess risk was also determined. It was found that the BMDL10 for serum insulin and serum amylase was 3.7 and 5.3 microg/g Cr, respectively. Compared to the BMDL for renal damage caused by Cd exposure, identified by the effect biomarkers urinary beta2-microglobulin, urinary N-acetyl-beta-glucosaminidase, and urinary albumin (UALB), it was shown that BMDL10 for serum insulin is the lowest among all values and UALB gave the highest value (5.8 microg/g Cr). This study indicates that Cd exposure can result in pancreatic dysfunction and the effect appears at lower urinary Cd level than renal dysfunction. The endocrine function of the pancreas was affected at lower urinary levels of Cd, compared to the exocrine function, which was seen at higher urinary levels of Cd than those giving rise to renal tubular dysfunction.

Although often clinically silent, pancreatic cellular injury (PCI) is relatively frequent after cardiac surgery with cardiopulmonary bypass; and its etiology and time course are largely unknown. We defined PCI as the simultaneous presence of abnormal values of pancreatic isoamylase and immunoreactive trypsin (IRT). The frequency and time evolution of PCI were assessed in this condition using assays for specific exocrine pancreatic enzymes. Correlations with inflammatory markers were searched for preoperative risk factors. One hundred ninety-three patients submitted to cardiac surgery were enrolled prospectively. Blood IRT, amylase, pancreatic isoamylase, lipase, and markers of inflammation (alpha1-protease inhibitor, alpha2-macroglobulin, myeloperoxidase) were measured preoperatively and postoperatively until day 8. The postoperative increase in plasma levels of pancreatic enzymes and urinary IRT was biphasic in all patients: early after surgery and later (from day 4 to 8 after surgery). One hundred thirty-three patients (69%) experienced PCI, with mean IRT, isoamylase, and alpha1-protease inhibitor values higher for each sample than that in patients without PCI. By multiple regression analysis, we found preoperative values of plasma IRT >or=40 ng/mL, amylase >or=42 IU/mL, and pancreatic isoamylase >or=20 IU/L associated with a higher incidence of postsurgery PCI (P < 0.005). In the PCI patients, a significant correlation was found between the 4 pancreatic enzymes and urinary IRT, total calcium, myeloperoxidase, alpha1-protease inhibitor, and alpha2-macroglobulin. These data support a high prevalence of postoperative PCI after cardiac surgery with cardiopulmonary bypass, typically biphasic and clinically silent, especially when pancreatic enzymes were elevated preoperatively.

We have employed an oral test of pancreatic digestive function using fluorescein dilaurate (a substrate for pancreatic cholesterol ester hydrolase), administered together with pancreatic enzyme supplements, in order to test the hypothesis that urinary excretion of fluorescein provides a simple method for determining the optimal dose of oral pancreatic enzymes. Commercially available pancreatic enzyme supplements had negligible cholesterol hydrolase activity in vitro, and did not increase the urinary excretion of fluorescein when administered together with fluorescein dilaurate in 16 patients with pancreatic exocrine insufficiency. Inhibition of gastric secretion by ranitidine resulted in a statistically significant increase in urinary fluorescein excretion during the fluorescein dilaurate test. The fluorescein dilaurate test is not, therefore, suitable for determining the effectiveness of oral pancreatic enzyme replacement therapy. Moreover, the manufacturer's advice to stop oral pancreatic enzyme therapy for 5 days before performing the fluorescein dilaurate test appears unnecessary, since oral pancreatic enzymes do not alter test results.

P-Amino-benzoic acid (PABA) is split specifically by pancreatic chymotrypsin from the synthetic tripeptide N-benzoyl-L-tyrosyl-PABA. The urinary excretion of absorbed PABA serves as an index for exocrine pancreatic function. The peptide (0.015 g/kg) was administered orally to 20 controls (aged between 5 months and 16 years), 6 patients with exocrine pancreatic insufficiency caused by cystic fibrosis (CF), and 9 newborn infants. In the controls the mean 6-hour PABA recovery was 58.5% (+/- 11.2 SD). Recovery in patients with CF was lower (P less than 0.001) with no overlap. In newborn infants the mean 6-hour PABA recovery was 23.4 (+/- 17.7 SD); overlapping in 3 instances with the results in CF patients. This simple, noninvasive test thus appears promising and merits further investigation in younger infants, especially newborns.