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Due to the importance of intestinal transport in pharmacological studies and the emerging role of intestinal signalling activity in the gut-liver axis, we have developed a new method to investigate intestinal transport and liver signalling using cell and serum free mesenteric perfusion system in the rat. The method regarding bile acid active absorption was validated, then, the portal venous content was examined for fibroblast growth factor 15(FGF15), a putative signalling protein produced by the ileal enterocytes following bile acid absorption. After isolation and cannulation of the relevant vessels (abdominal aorta and portal vein), the abdominal aorta and the terminal ileum were infused with respectively Krebs-Ringer solution and tauroursodeoxycholate (TUDCA) and the absorption was assessed by its recovery in the portal vein. After immunoblot, liquid chromatography and mass spectrometry analysis were performed both on gel bands digestion products and on portal outflow samples in order to evaluate if negligible amounts of FGF15 were present in the portal circulation. TUDCA absorption was efficient, intestinal morphology and oxygen consumption were normal. Despite accurate analysis, we could not find FGF15. Our method proved to be reliable for studying the active bile acid absorption. It is also suitable to identify molecules produced by enterocytes and transferred to the portal circulation in response to absorption of different substances such as nutrients or drugs. Since FGF15 was not recovered we suggest the possibilities that this protein is produced in very little amounts, poorly transferred outside the cell, or that it is extremely unstable and rapidly degraded.

AbstractBackground:Among the various studies of pancreatic function in the elderly published so far, none have dealt with subjects over 90 years of age. The aim of this study was to examine pancreatic function in healthy individuals over 90 years old. Methods:Sixty-eight healthy noninstitutionalized elderly persons, aged 91–104 years, with a mean age of 95 years, and 63 younger controls were studied. Pancreatic function was studied by determining fecal elastase 1 concentration. In addition to this test, we also measured serum amylase, pancreatic isoamylase and lipase in 53 of the 68 elderly subjects. Results:All but 1 of the 68 elderly subjects had normal elastase 1 values; the one who did not had a value slightly below normal. No significant difference with controls was found. Serum pancreatic enzymes were normal in almost all of the 53 elderly studied; 3 had a mild elevation only of amylase and 1 had a persistent elevation of amylase, pancreatic isoamylase and lipase. Conclusions:In subjects over 90 years of age, exocrine pancreatic function continues to be normal; if an impairment occurs, it is mild and not significant for digestion of food. In addition, serum pancreatic enzymes remain within normal limits in the vast majority of cases.Copyright © 2009 S. Karger AG, Basel and IAP

Background:Among the various studies of pancreatic function in the elderly published so far, none have dealt with subjects over 90 years of age. The aim of this study was to examine pancreatic function in healthy individuals over 90 years old. Methods:Sixty-eight healthy noninstitutionalized elderly persons, aged 91–104 years, with a mean age of 95 years, and 63 younger controls were studied. Pancreatic function was studied by determining fecal elastase 1 concentration. In addition to this test, we also measured serum amylase, pancreatic isoamylase and lipase in 53 of the 68 elderly subjects. Results:All but 1 of the 68 elderly subjects had normal elastase 1 values; the one who did not had a value slightly below normal. No significant difference with controls was found. Serum pancreatic enzymes were normal in almost all of the 53 elderly studied; 3 had a mild elevation only of amylase and 1 had a persistent elevation of amylase, pancreatic isoamylase and lipase. Conclusions:In subjects over 90 years of age, exocrine pancreatic function continues to be normal; if an impairment occurs, it is mild and not significant for digestion of food. In addition, serum pancreatic enzymes remain within normal limits in the vast majority of cases.

We measured fecal elastase-1 (FE1) levels in 34 preterm newborns (15 small-for-gestational-age and 19 appropriate-for-gestational-age) during the first 2 months of life and evaluated whether they were correlated with nitrogen loss in stools. FE1 increased over time, and values were similar in both groups of newborns. Fecal nitrogen was significantly higher in small-for-gestational-age infants. There was no correlation between FE1 levels and fecal nitrogen excretion. Pancreatic proteolytic function was efficient at an early stage in enterally fed preterm newborns. Despite the similar FE1 values, fecal nitrogen loss was significantly higher in small-for-gestational-age preterm infants than in appropriate-for-gestational-age preterm infants.

We measured fecal elastase-1 (FE1) levels in 34 preterm newborns (15 small-for-gestational-age and 19 appropriate-for-gestational-age) during the first 2 months of life and evaluated whether they were correlated with nitrogen loss in stools. FE1 increased over time, and values were similar in both groups of newborns. Fecal nitrogen was significantly higher in small-for-gestational-age infants. There was no correlation between FE1 levels and fecal nitrogen excretion. Pancreatic proteolytic function was efficient at an early stage in enterally fed preterm newborns. Despite the similar FE1 values, fecal nitrogen loss was significantly higher in small-for-gestational-age preterm infants than in appropriate-for-gestational-age preterm infants.

Ursodeoxycholic acid (UDCA), previously used for cholesterol gallstone dissolution, is currently considered the first choice therapy for many forms of cholestatic syndromes. Many mechanisms and sites of action have been proposed for UDCA, but definitive data are still missing regarding the key points of its efficacy and optimal dosage in order to achieve a sustained clinical effect. Among the suggested mechanisms of action of UDCA, changes in bile acid pool composition, hepatocyte membrane protection, immunomodulatory effects and bicarbonate-rich hypercholeresis have been extensively studied. However, recent evidence indicate that UDCA is a potent intracellular signalling agent that counterbalances impaired biliary secretion, inhibits hepatocyte apoptosis and protects injured cholangiocytes against toxic effects of bile acids. It is clear that the relative contribution of these mechanisms to the anticholestatic action of UDCA depends on the type and stage of the liver injury. Available clinical evidence suggest that UDCA treatment has to be initiated as early as possible and that higher doses could be more efficacious in inducing and maintaining clinical remission of cholestatic diseases. The future availability of UDCA derivatives will possibly enhance the chances to effectively treat chronic cholestatic diseases.

An isoenzyme of pyruvate kinase (Tu M2-PK) is overexpressed by tumor cells and can be measured in blood by a specific immunoenzymatic assay. Our objective was to investigate the diagnostic value of Tu M2-PK in comparison with that of CA 19-9 in pancreatic cancer. We studied 265 subjects: 60 with histologically confirmed pancreatic cancer, 43 with benign pancreatic diseases (acute and chronic pancreatitis), 5 with benign cystic neoplasms of the pancreas, 9 with neuroendocrine tumors, 77 with other abdominal malignancies, 47 with benign digestive diseases, and 24 healthy controls. Levels of plasma Tu M2-PK and serum CA 19-9 were determined by commercially available specific immunoassays. The diagnostic sensitivity and specificity of Tu M2-PK for pancreatic cancer were 85 and 41%, respectively, while those of CA 19-9 were 75 and 81%. The combination of the two tests significantly increased sensitivity (97%) but lowered specificity (38%). In discriminating between pancreatic cancer and acute or chronic pancreatitis, Tu M2-PK turned out to be less accurate than CA 19-9. In patients without pancreatic tumor, cholestasis appeared not to affect the values of Tu M2-PK, while CA 19-9 was found to be significantly higher. Tu M2-PK was also abnormally high in the majority of patients with other digestive malignancies or neuroendocrine tumors. The results demonstrate that Tu M2-PK has a satisfactory sensitivity but a poor specificity in the diagnosis of pancreatic cancer. Used together with CA 19-9, the sensitivity increases considerably.

To evaluate pancreatic exocrine function in uremia, 25 patients undergoing regular hemodialysis without clinical evidence of pancreatic disease and 25 healthy control subjects were studied by fecal elastase 1 and chymotrypsin. Abdominal ultrasonography and measurement of serum lipase, calcium, phosphate, and parathormone were also carried out. Fecal elastase was significantly lower (P < 0.001)in patients than in controls. Abnormally low values were found in 12/25 patients of whom six had values <100 μg/g. Fecal chymotrypsin was significantly lower (P < 0.05)in patients than in controls, with lower than normal values found in 10/25 patients. Fecal elastase was not related to the serum calcium, phosphate, or parathormone levels or to the period of dialysis. In patients serum lipase was normal or slightly elevated (<300 units/liter), and there was no evidence of pancreatic disease at ultrasound examination. The results lend further support to the existence of pancreatic function impairment in a significant number of patients with renal failure despite the absence of clinical and morphological evidence of pancreatic disease.

As immunosuppressive agents, corticosteroids maybe considered an appropriate treatment for primarybiliary cirrhosis, even if bone loss and other sideeffects may occur. We studied biliary lipid metabolism in 10 nonicteric patients, with histologicallyproven primary biliary cirrhosis (stage I-IV). Weadministered methylprednisolone (24 mg daily) for 30days to ascertain its effects on biliary lipidmetabolism, which are largely still unknown. All patientsunderwent a 30-day drug-washout period before enteringthe trial. The following parameters were studied beforeand after methylprednisolone treatment: serum biochemistry; cholic acid pool size, kineticsand synthesis; biliary lipid secretion; biliary bileacid pattern; biliary lipid molar percentage; andcholesterol saturation index. Methylprednisolone induced a statistically significant (Wilcoxon ranktest) increase in cholic acid turnover (from 0.26± 0.04 to 0.50 ± 0.05 K/day, P = 0.005)and synthesis (from 0.42 ± 0.12 to 0.78 ±0.11 mmol/day, P = 0.04), and in bile deoxycholic acid molarpercentage (from 19.4 ± 2.7 to 30.6 ± 4.4%molar, P = 0.01). On the other hand, a significantdecrease in biliary cholesterol molar percentage (from7.9 ± 0.7 to 6.4 ± 0.5 % molar, P =0.005), cholesterol saturation index (from 1.11 ±0.11 to 0.95 ± 0.07, P = 0.05), and biliarycholesterol secretion (from 64.7 ± 5.4 to 53.0± 4.5 μmol/hr, P = 0.005) was observed. These findings show thatshort-term administration of methylprednisolone inpatients with primary biliary cirrhosis does not induceexpansion of the cholic acid pool but increases cholicacid synthesis and turnover, as well as intestinalproduction of deoxycholic acid. If long-term treatmentis considered, the beneficial immunosuppressive effectsof corticosteroids have to be weighed against the hepatotoxic properties of deoxycholicacid.

Obesity is a condition associated with an increased frequency of gallstone disease. This study attempted to evaluate the comparative effects of two gallstonedissolving agents, chenodeoxycholic acid and ursodeoxycholic acid, on bile acid metabolism and biliary lipid secretion in obese subjects in order to identify the bile acid of choice in preventing and treating gallstone disease in obesity. Twenty obese subjects (> 120% ideal body wt) were randomly treated with ursodeoxycholic acid (10 mg · kg−1· day−1· 1 mo−1) and then with chenodeoxycholic acid (15 mg · kg−1· day−1· 1 mo−1) or with chenodeoxycholic acid first and then with ursodeoxycholic acid. Patients 1–10 were studied while eating an unrestricted weightmaintenance diet, whereas patients 11–20 were eating a 1080-kcal/d hypocaloric diet. Biliary lipid composition, cholesterol saturation index, and biliary bile acid pattern were evaluated in all subjects before and after each treatment period; in subjects 6–10 and 16–20, biliary lipid secretion rates and bile acid pool size were also evaluated. Both ursodeoxycholic acid and chenodeoxycholic acid decreased cholesterol outputs and cholesterol saturation index. However, during the weight-maintenance period the decrease induced by chenodeoxycholic acid was not significant. Biliary cholesterol outputs and cholesterol saturation index were always lower during ursodeoxycholic acid administration than during chenodeoxycholic acid therapy. Ursodeoxycholic acid levels during ursodeoxycholic acid administration and chenodeoxycholic acid levels during chenodeoxycholic acid administration increased in bile to 50% and 77%, respectively, of total bile acid levels. Bile acid pool size remained unchanged during chenodeoxycholic acid administration and was significantly reduced by ursodeoxycholic acid administration during the weight-reduction period. In conclusion, ursodeoxycholic acid in obese subjects seems more effective than chenodeoxycholic acid, at least during weight maintenance, in reducing cholesterol saturation of bile. This effect is related to a significant decrease of biliary cholesterol output.

An enzyme immunoassay was used to determine benzo[a ]pyrene (BaP) in smoked meat products and other samples of food and environmental origin. The method used has a detection limit (3 σ) of 0.1 μg kg⁻¹ and a coefficient of variation less than 10%. The main aim of the study was to compare the possible influence of different smoking processes and packaging material on the amount of BaP deposited on smoked meat product, mainly different sausages. The lowest amount of BaP was found when smoke produced by steam in the indirect method smoking-chamber was used. A slightly protective effect of polyamide casing was noted. © 1999 Society of Chemical Industry

1. Isolated rat livers were perfused in a single pass with increasing doses of taurocholate with and without albumin in the perfusion media. 2. The kinetics of taurocholate uptake were thus evaluated. 3. In all the experiments, taurocholate uptake showed Michaelis-Menten kinetics. Increasing the albumin concentration in the medium resulted in an increase in the Km, without effect on the Vmax. When taurocholate and albumin were kept constant (20:1 molar ratio), the Vmax was significantly lower than in the other experiments. 4. These data suggest that taurocholate uptake shows saturation in the absence of albumin and that albumin reduces taurocholate uptake.