Intraoperative amylase level of pancreatic juice as a simple predictor of pancreatic fistula after pancreaticoduodenectomy.

INTRODUCTION: A soft remnant texture of the pancreas is commonly accepted as a risk factor for postoperative pancreatic fistula (POPF) after pancreaticoduodenectomy (PD). However, its assessment is subjective. The aim of this study was to evaluate the significance of intraoperative amylase level of the pancreatic juice as a risk factor of POPF after PD. METHOD: This study included 75 patients who underwent PD between November 2014 and April 2020 at Jikei University Hospital. We investigated the relationship between pancreatic texture, intraoperative amylase level of pancreatic juice, results of the pathological evaluations, and the incidence of POPF. RESULTS: Twenty-three patients (31%) developed POPF. The significant predictors of POPF were non-ductal adenocarcinoma (p < 0.01), soft pancreatic remnant (p < 0.01), high intraoperative blood loss (p < 0.01), high intraoperative amylase level of pancreatic juice (p < 0.01), and low pancreatic fibrosis (p < 0.01). Multivariate analysis revealed that the significant independent predictors of POPF were high intraoperative blood loss (p < 0.01) and high intraoperative amylase level of pancreatic juice (p = 0.02). Receiver operating characteristic (ROC) analysis showed that the cut-off value for the intraoperative amylase level of pancreatic juice was 2.17 × 105 IU/L (area under the curve = 0.726, sensitivity = 95.7%, and specificity = 50.0%) CONCLUSIONS: The intraoperative amylase level of pancreatic juice is a reliable objective predictor for POPF after PD.

Analysis of lipase activity in duodenal juice. Comparison of an automated spectrophotometric assay to a fluorometric microplate assay, and factors affecting sample stability.

BACKGROUND: Direct pancreas function testing (DPFT) has been regarded as gold standard for assessment of exocrine pancreas function. One of the outcomes from DPFT is pancreatic lipase activity in duodenal juice, but no standard assay for measuring pancreas lipase activity in duodenal juice exists. AIMS: To optimize and evaluate an autoanalyzer assay for measuring lipase activity in duodenal juice. METHODS: We used samples of duodenal juice from our biobank, collected through a short endoscopic secretin test in patients with suspected exocrine pancreas insufficiency. Samples were analyzed on a Cobas autoanalyzer (Roche Diagnostics), using a colorimetric, kinetic enzyme activity assay. We compared stability of samples diluted in saline to samples diluted in 3-(N-morpholino) propane sulfonic acid (MOPS) buffer added bovine serum albumin (BSA). Results from the Cobas assay were compared to Confluolip method, a fluorometric, kinetic enzyme assay, modified to fit into a microplate setting. RESULTS: We tested the stability of 54 samples from 21 patients. Diluting samples with MOPS buffer added BSA gave stable results, and was superior to diluting samples in saline. We compared the two assays in 50 samples from 20 patients and found a good correlation between the two assays (r = 0.91, p < .001). There was a significant proportional bias between the two assays, but no significant systematic bias. CONCLUSION: Pancreatic lipase activity in duodenal juice samples diluted in MOPS buffer added BSA is stable for one hour at room temperature. Quantification of lipase activity in duodenal juice using a standard automated activity assay has comparable accuracy to a manual fluorometric method.

Intra-Operative Amylase Concentration in Peri-Pancreatic Fluid Predicts Pancreatic Fistula After Distal Pancreatectomy.

Post-operative pancreatic fistula (POPF) is a potentially severe complication following distal pancreatectomy. The aim of this study was to assess the predictive value of intra-operative amylase concentration (IOAC) in peri-pancreatic fluid after distal pancreatectomy for the diagnosis of POPF. Consecutive patients who underwent a distal pancreatectomy between November 2014 and September 2016 were included in the analysis. IOAC was measured, followed by drain fluid analysis for amylase on post-operative days (PODs) 1, 3, and 5. Receiver operator characteristic (ROC) analysis was performed to evaluate the discriminative capacity of IOAC as a predictor of POPF. IOAC was measured after distal pancreatectomy in 26 patients. The IOAC correlated significantly with (i) PODs 1, 3, and 5 drain amylase (p < 0.01); (ii) the development of POPF (p < 0.01); and (iii) the Clavien-Dindo grade of surgical complications (p = 0.02). Eighty-three percent of patients with an IOAC > 1000 experienced a post-operative complication (OR 18.3, 95% CI 2.51-103, p < 0.01). ROC curve analysis confirmed the predictive relationship of IOAC and POPF as an excellent test with an area under the curve of 0.92 (95% CI 0.81-0.99, p < 0.01). Measurement of IOAC allows early and accurate categorization of patients at risk for POPF in distal pancreatectomy.

Intra-operative amylase in peri-pancreatic fluid independently predicts for pancreatic fistula post pancreaticoduodectomy.

BACKGROUND: Post-operative pancreatic fistula (POPF) is a common and potentially life-threatening complication following pancreaticoduodectomy. The aim of this study was to assess the predictive value of intra-operative amylase concentration (IOAC) in peri-pancreatic fluid after resection for the diagnosis of POPF. METHODS: Consecutive patients who underwent a pancreaticoduodectomy between September 2014 and October 2015 were included in the analysis. IOAC was measured intraoperatively followed by drain fluid analysis for amylase on post-operative days (POD) 1, 3 and 5. Receiver operator characteristic (ROC) analysis was performed to evaluate the discriminative capacity of IOAC as a predictor of POPF. RESULTS: IOAC was measured after pancreaticoduodectomy in 62 patients. The IOAC correlated significantly with i) POD 1 and 3 drain amylase (p < 0.01), ii) the development of POPF (p < 0.01), iii) the development of clinically relevant fistula (Type B, C) (p < 0.01), iv) delayed gastric emptying (p < 0.01), and v) grade of complication as per the Clavien-Dindo definition (p = 0.02). ROC curve analysis confirmed the predictive relationship of IOAC and POPF as a good test with an area under the curve of 0.93, 95% CI 0.87-0.99, p < 0.01. In patients with IOAC of 200 U/L or higher the POPF rate was 80% (OR = 50.1, p < 0.0001). DISCUSSION: Measurement of IOAC allows early and accurate categorization of patients at risk for POPF.

Externalized decondensed neutrophil chromatin occludes pancreatic ducts and drives pancreatitis.

Ductal occlusion has been postulated to precipitate focal pancreatic inflammation, while the nature of the primary occluding agents has remained elusive. Neutrophils make use of histone citrullination by peptidyl arginine deiminase-4 (PADI4) in contact to particulate agents to extrude decondensed chromatin as neutrophil extracellular traps (NETs). In high cellular density, NETs form macroscopically visible aggregates. Here we show that such aggregates form inside pancreatic ducts in humans and mice occluding pancreatic ducts and thereby driving pancreatic inflammation. Experimental models indicate that PADI4 is critical for intraductal aggregate formation and that PADI4-deficiency abrogates disease progression. Mechanistically, we identify the pancreatic juice as a strong instigator of neutrophil chromatin extrusion. Characteristic single components of pancreatic juice, such as bicarbonate ions and calcium carbonate crystals, induce aggregated NET formation. Ductal occlusion by aggregated NETs emerges as a pathomechanism with relevance in a plethora of inflammatory conditions involving secretory ducts.

Telomerase activity in pancreatic juice differentiates pancreatic cancer from chronic pancreatitis: A meta-analysis.

BACKGROUND/OBJECTIVE: To evaluate the usefulness of genetic markers in pancreatic juice (PJ), and the combination of these markers with telomerase activity in the differential diagnosis of pancreatic ductal adenocarcinoma (PDAC) from chronic pancreatitis. METHODS: We conducted a meta-analysis for the diagnostic utility of the four major altered genes in PDAC (KRAS, CDKN2A/p16, TP53, and SMAD4/DPC4), telomerase activity, and a combination assay using PJ samples. A literature search was conducted in MEDLINE, Cochrane Library, and Web of Science. Data were pooled and presented as diagnostic sensitivity and specificity with 95% confidence intervals (CIs). RESULTS: Thirty-nine studies fulfilled the inclusion criteria. Pooled estimates of KRAS analysis were as follows: sensitivity was 0.67 (95% CI, 0.63-0.71) and specificity, 0.82 (95% CI, 0.79-0.85). For telomerase activity analysis, sensitivity was 0.82 (95% CI, 0.76-0.87) and specificity, 0.96 (95% CI, 0.90-0.99). The other three tumor suppressors demonstrated low sensitivity. The data did not suggest any publication bias. A combined analysis of KRAS and telomerase activity showed a higher diagnostic sensitivity (0.94; 95% CI, 0.83-0.99) than KRAS alone. A combined analysis of telomerase activity and cytology revealed more reliable diagnostic accuracy than telomerase activity alone, with high sensitivity (0.88; 95% CI, 0.74-0.96) and specificity (1.00; 95% CI, 0.91-1.00). CONCLUSIONS: The most reliable marker in PJ samples for diagnosis of PDAC was telomerase activity. Telomerase activity can play a central role in diagnostic analysis using PJ samples, and can increase diagnostic accuracy when combined with KRAS mutations or cytological examination.

Relationships between leucine and the pancreatic exocrine function for improving starch digestibility in ruminants.

Four Holstein heifers (215 ± 7 kg; means ± SD), fitted with one pancreatic pouch, duodenal re-entrant cannulas, and duodenal infusion catheters, were used in this experiment. In phase 1, the 24-h profile of pancreatic fluid was determined. Pancreatic fluid flow peaked 1h after feeding, but peaks of similar magnitude also occurred before the morning feed, necessitating 24-h collection of pancreatic fluid to estimate daily excretion. In phase 2, the effects of duodenal infusions of 0, 10, 20, or 30 g of leucine on pancreatic fluid flow were determined in a 4 × 4 Latin square design. The leucine was infused for 12h in 2,500 mL of the infusate, and samples of pancreatic fluid and jugular blood were collected in 1-h intervals from the beginning of the infusion for 36 h. The results showed that the secretion rate of pancreatic fluid (mL/h) was significantly higher in 10-g leucine group than the other groups (mL/h). Protein concentration (mg/mL) in pancreatic fluid was elevated proportional to the amount of leucine infused. Leucine infusions increased both the concentration (U/mL) and secretion rate (U/h) of α-amylase. Infusion of 10 g of leucine also increased the secretion rates (U/h) of trypsin, chymotrypsin, and lipase, but did not change their concentrations. No significant effects of leucine infusions on plasma glucose and insulin concentrations were found. The results indicate that leucine could act as a nutrient signal to stimulate α-amylase production and pancreatic exocrine function in dairy heifers.

Quantitative assessment of the diagnostic role of human telomerase activity from pancreatic juice in pancreatic cancer.

Many studies have shown that human telomerase activity could play potential role as a diagnostic biomarker of pancreatic cancer (PaC). The aim of this meta-analysis is to summarize the clinical value of human telomerase activity in the diagnosis of PaC. Eligible studies from PubMed, Embase, the Cochrane Library, Web of Science, Ovid, Sci Verse, Science Direct, Scopus, BioMed Central, Biosis previews, Chinese Biomedical Literature Database (CBM), Chinese National Knowledge Infrastructure (CNKI), Technology of Chongqing (VIP), and Wan Fang databases were searched concerning the diagnostic value of human telomerase activity in PaC without language restriction. The quality of each study was scored with the Quality Assessment of Diagnostic Accuracy Studies (QUADAS). Sensitivity, specificity, positive and negative likelihood ratios (PLR and NLR, respectively), and diagnostic odds ratio (DOR) for human telomerase activity in the diagnosis of PaC were pooled. Summary receiver operating characteristic (SROC) curve analysis and the area under the curve (AUC) were used to estimate the overall test performance. Evidence of heterogeneity was evaluated using the Chi-square and I (2) test. Meta-Disc 1.4 and Stata 12.0 software were used to analyze the data. Nine studies with a total 186 PaC patients and 132 control individuals were included in this meta-analysis. All of the included studies are of high quality (QUADAS score ≥10). The summary estimate was 0.83 (95 % confidence interval (CI), 95 % CI = 0.77-0.88) for sensitivity and 0.72 (95 % CI = 0.64-0.79) for specificity. The positive likelihood (PLR), negative likelihood (NLR), and diagnostic odds (DOR) ratios were 3 (95 % CI = 1.67-5.41), 0.25 (95 % CI = 0.13-0.46), and 3 (95 % CI = 4.91-43.23), respectively. The area under the summary ROC curve (AUC) and Q* index for the diagnosis of PaC were 0.88 and 0.81, respectively. Our study demonstrates that telomerase could be a useful tumor marker for PaC diagnosis. Although more studies are needed to highlight the theoretical strengths, these results will provide theoretical basis for bringing telomerase activity detection into PaC screening plan.

Is the enteral replacement of externally drained pancreatic juice valuable after pancreatoduodenectomy?

PURPOSES: External drainage of pancreatic juice using a pancreatic duct stent following pancreatoduodenectomy is widely performed. We hypothesized that the replacement of externally drained pancreatic juice would help to prevent postoperative complications, including pancreatic fistulas. METHODS: Sixty-four patients who underwent pancreatoduodenectomy between 2006 and 2008 were randomly assigned to either a pancreatic juice non-replacement (NR) or replacement (R) group. Eighteen patients were excluded from the analysis because they had unresectable tumors (n = 4), low pancreatic juice output (<100 ml) (n = 11) or for other reasons (n = 3). A total of 46 patients (NR = 24, R = 22) were included in the final analysis. The volume and amylase levels of externally drained pancreatic juice were analyzed on postoperative days 7 and 14. The incidence of postoperative complications, including pancreatic fistulas and delayed gastric emptying, was also assessed. RESULTS: The total amylase secretion from the pancreatic tube on postoperative day 7 was significantly higher in the NR group compared with the R group (P = 0.044). The incidence of pancreatic fistulas (>Grade B) was also significantly higher in the NR group (33.3 vs. 9.1 %, P = 0.046). CONCLUSIONS: In cases for whom external pancreatic juice drainage from a stent is applied following pancreaticojejunostomy, enteral replacement of externally drained pancreatic juice may reduce the incidence of postoperative pancreatic fistula formation.

In vitro effects of proteases in human pancreatic juice on stability of liquid and carrier-bound fibrin sealants.

BACKGROUND: Fibrin sealants are used in pancreatic surgery to prevent leakage of pancreatic fluid and reduce associated complications. The efficacy of this approach is unclear. METHODS: Fibrin clots were generated in vitro from two commercially available liquid fibrin sealants (Tissucol Duo® and Evicel®) and the carrier-bound fibrin sealant Tachosil®, and exposed to normal saline or human pancreatic fluid. Stability of the sealants was assessed by release of the fibrin and collagen degradation products, D-dimer and hydroxyproline. The effect of protease inhibitors on sealant breakdown was assessed. RESULTS: Clots generated from liquid fibrin sealants degraded rapidly in pancreatic fluid, but not in normal saline. D-dimer release from fibrin clots by pancreatic fluid was approximately 1700 µg/ml after 24 h and less than 20 µg/ml by saline. Pancreatic fluid, but not normal saline, degraded both the fibrin and collagen component of Tachosil®. After 6 h, mean(s.e.m.) D-dimer levels in pancreatic fluid exposed to Tachosil® were 850(183) ng/ml, compared with 60(6) ng/ml in normal saline. The mean(s.e.m.) hydroxyproline concentration in pancreatic fluid was 497(17) µg/ml after a 24-h exposure to Tachosil®, compared with 26(12) µg/ml in normal saline. Protease inhibitors significantly inhibited breakdown of liquid sealants (D-dimer levels less than 50 µg/ml after 24 h) and Tachosil® (D-dimer release 179(12) ng/ml at 6 h; hydroxyproline release 181(29) µg/ml at 24 h). CONCLUSION: Proteases in pancreatic juice effectively degrade both liquid and carrier-bound fibrin sealants in vitro. The use of these products in pancreatic surgery with the aim of preventing leakage of pancreatic fluid is not supported by this experimental study.

Effect of simulated gastric and intestinal digestion on temporal stability and immunoreactivity of peanut, almond, and pine nut protein allergens.

Current models of digestibility utilize pepsin stability to assess the safety of allergenic versus nonallergenic food proteins. Dietary protein digestion in vivo, however, requires acid denaturation and protease cleavage by pepsin, trypsin, and/or chymotrypsin. The ability of this approach to identify food protein stability in the mammalian gut may be limited. We determined the temporal stability and immunoreactivity of almond, pine nut, and peanut allergenic proteins under simulated physiologic gastric and intestinal digestive conditions in vitro. Gel electrophoresis and immunoblot analyses were used to determine protein stability and immunoreactivity, respectively. Peanut, almond, and pine nut proteins were pepsin- and pancreatin-stable and immunoreactive for up to 1 h after initiation of digestion. Moreover, successive acid denaturation and pepsin and pancreatin cleavage were necessary to hydrolyze these allergenic proteins and reduce their IgG- and IgE-binding capacity, which suggests that digestibility models must be improved for more accurate safety assessment of food allergens.

Changes in total and individual crocetin esters upon in vitro gastrointestinal digestion of saffron aqueous extracts.

Changes that may be expected in crocetin esters (crocins) upon digestion were examined in saffron aqueous extracts for the first time. Chemical characterization of total and individual crocins and other bioactive compounds was achieved by UV-vis spectrophotometry, RP-HPLC-DAD, and LC-ESI-MS. Antioxidant activity was evaluated using in vitro assays and the comet assay. The observed loss for both total and trans-crocins was higher in saffron (∼50%) than in gardenia extracts (∼30%), which were also examined for comparison. Loss was lower than that reported for hydrophobic carotenoids. cis-Isomers were less affected, leading to the hypothesis that trans/cis isomerization may occur in parallel to degradation reactions. Monitoring changes in the extracts at oral, gastric, or intestinal phases, separately, verified this view pointing out the critical effect of pH, temperature, and duration of process but not of digestive enzymes. No isomerization and less degradation (<20% loss) was evidenced when pure trans-crocetin (di-ß-D-gentiobiosyl) ester was subjected to gastric or intestinal conditions.

Cancer detection by ubiquitin carboxyl-terminal esterase L1 methylation in pancreatobiliary fluids.

AIM: To evaluate the utility of measuring epigenetic alterations in pancreatic and biliary fluids in determining molecular markers for pancreatobiliary cancers. METHODS: DNA was extracted from undiluted pancreatic and biliary fluids. As a surrogate for a genome-wide hypomethylation assay, levels of long interspersed nuclear element-1 (LINE-1) methylation were analyzed using bisulfite pyrosequencing. CpG island hypermethylation of 10 tumor-associated genes, aryl-hydrocarbon receptor repressor, adenomatous polyposis coli, calcium channel, voltage dependent, T type α1G subunit, insulin-like growth factor 2, O-6-methyl-guanine-DNA methyltransferase, neurogenin 1, CDKN2A, runt-related transcription factor 3 (RUNX3), secreted frizzled-related protein 1, and ubiquitin carboxyl-terminal esterase L1 (UCHL1), was analyzed using MethyLight. To examine the role of CpG methylation and histone deacetylation in the silencing of UCHL1, human gallbladder carcinoma cell lines and pancreatic carcinoma cell lines were treated with 2 or 5 µmol/L 5-AZA-dC for 72 h or 100 nmol/L Trichostatin A for 24 h. After the treatment, UCHL1 expression was analyzed by real-time reverse transcription-polymerase chain reaction. RESULTS: Pancreatobiliary cancers exhibited significantly lower LINE-1 methylation levels in pancreatic and biliary fluids than did noncancerous pancreatobiliary disease (58.7% ± 4.3% vs 61.7% ± 2.2%, P = 0.027; 53.8% ± 6.6% vs 57.5% ± 1.7%, P = 0.007); however, LINE-1 hypomethylation was more evident in pancreatic cancer tissues than in pancreatic fluids (45.4% ± 5.5% vs 58.7% ± 4.3%, P < 0.001). CpG island hypermethylation of tumor-associated genes was detected at various frequencies, but it was not correlated with LINE-1 hypomethylation. Hypermethylation of the UCHL1 gene was cancer-specific and most frequently detected in pancreatic (67%) or biliary (70%) fluids from patients with pancreatobiliary cancer. As a single marker, hypermethylation of the UCHL1 gene in pancreatic and biliary fluids was most useful for the detection of pancreatic and pancreatobiliary cancers, respectively (100% specificity). Hypermethylation of the UCHL1 and RUNX3 genes in pancreatic and biliary fluids was the most useful combined marker for pancreatic (87% sensitivity and 100% specificity) and pancreatobiliary (97% sensitivity and 100% specificity) cancers. Treatment with a demethylating agent, 5-AZA-2'-deoxycytidine, restored UCHL1 expression in pancreatobiliary cancer cell lines. CONCLUSION: Our results suggest that hypermethylation of UCHL1 and RUNX3 in pancreatobiliary fluid might be useful for the diagnosis of pancreatobiliary cancers.

Antiobesity potential of ursolic acid stearoyl glucoside by inhibiting pancreatic lipase.

The present study was designed to evaluate the hypolipidemic effect of ursolic acid stearoyl glucoside (UASG) in high-fat diet-induced obesity. Two in vivo experiments such as high-fat diet-induced obesity mice model and lipid emulsion tolerance test in normal rats were performed. In vitro inhibition of pancreatic lipase activity was further measured to substantiate the results. In high-fat diet-induced obesity mice model, female Swiss mice were fed a high fat diet (HFD; 40% fat) with or without 1 or 2% of UASG or 0.012% orlistat for nine weeks. In lipid emulsion tolerance test male Wister rats were orally administered, lipid emulsion with or without 500 or 1000 mg/kg of UASG and the plasma triglycerides were measured from 0.5 to 5 h. Consumption of HFD containing UASG to mice for nine weeks exhibited significant reduction in lipid parameters, body weight, parametrial adipose tissue weight, liver triglyceride (TG) and different organ weight compared to HFD fed control. Further it was noted the improvement in insulin resistance induced by the HFD alone group. Furthermore, consumption of an HFD containing 1 or 2% of UASG significantly increased the fecal content and fecal triglyceride compared with the HFD group. Pre-treatment with UASG inhibited the elevated plasma triglyceride level after the oral administration of the lipid emulsion to rats. Further, UASG significantly inhibits activity of pancreatic lipase at a concentration of 2.5 mg/ml. Data obtained from the results indicated that UASG prevent high-fat diet-induced obesity in mice possibly by inhibiting pancreatic lipase activity.

Pancreatic lipase-colipase binds strongly to the thylakoid membrane surface.

BACKGROUND: Isolated thylakoid membranes, i.e. the photosynthetic membranes of green leaves, inhibit the activity of pancreatic lipase and colipase during hydrolysis of fat in vitro. This inhibition has been demonstrated to cause reduced food intake and improved hormonal and lipid profile in vivo. One of the reasons suggested for the inhibiting effect is binding of lipase-colipase to the thylakoid membrane surface. This prompted a study of the binding of lipase and colipase to thylakoids. RESULTS: The results showed that lipase and colipase strongly bind to the thylakoid membrane surface. The dissociation constant was determined at 1.2 × 10⁻8 mol L⁻¹; binding decreased after treatment of thylakoids with pepsin/trypsin to 1.0 × 10⁻7 and to 0.6 × 10⁻7 mol L⁻¹ after treatment with pancreatic juice. Similarly, delipidation of thylakoids caused a decrease in binding, the dissociation constant being 2.0 × 10⁻7 mol L⁻¹. CONCLUSION: The binding of pancreatic lipase-colipase to the thylakoid membrane is strong and may explain the inhibition of lipase-colipase activity by thylakoids. After treatment with proteases to mimic intestinal digestion binding is decreased, but is still high enough to explain the observed metabolic effects of thylakoids in vivo.

In vitro gastric and intestinal digestion of a walnut oil body dispersion.

An oil body dispersion (11.3% fat) was prepared by wet disintegration of walnuts and was then subjected to a two-step model of in vitro digestion. In a gastric environment, proteolysis by pepsin led to the destabilization and coalescence of the oil bodies. Aggregation of the coalesced oil bodies was apparent under a confocal microscope, with aggregates up to 275 µm in size. Pepsin-resistant peptides and proteins remained at the surface of the oil bodies, and some were further resistant to intestinal proteases. Under intestinal conditions, the hydrolysis of walnut triglycerides led to the spontaneous formation of a new type of multiple emulsions, ranging from 2 to 45 µm in size and with protein material inside the inner water droplets. Transmission electron microscopy revealed the presence of a liquid-crystalline phase of bile salts and lipolytic products at the surface of the oil droplets and some bile salt crystals at the surface of the inner water droplets.

[Influence of pancreatic segment graft autotransplantation on its exocrine function].

In experiments on dogs the exocrine secretion of pancreatic segment graft after its autotransplantation and of pancreatic stamps after proximal resection of the pancreas was investigated. More significant impairment of the exocrine secretion of the pancreas was revealed in animals after pancreatic graft autotransplantation in comparison with animals after the proximal resection of the pancreas. Maintenance of the adaptation of pancreatic exocrine secretion to the nutritional composition of the intestinal contents and "generalized inhibition" of pancreatic exocrine secretion caused by duodenal trypsin infusion was revealed in all groups.

Coupling in vitro gastrointestinal lipolysis and Caco-2 cell cultures for testing the absorption of different food emulsions.

There is a growing interest in the optimization of dietary emulsions for monitoring postprandial lipid metabolism in the frame of preventing metabolic diseases. Using various emulsions, we investigated in a systematic scheme the combination of (i) in vitro gastrointestinal lipolysis and (ii) absorption and metabolism of lipolysis media in Caco-2 cells. Four emulsions based on either milk fat olein (OL) or rapeseed oil (RA) as the dispersed phase and either lecithin (LE) or sodium caseinate (CA) as the emulsifier were tested. After a sequential incubation of these emulsions with gastric and pancreatic enzymes, lipolysis media were incubated with Caco-2 cells, after dilution (1 : 20) to maintain the barrier integrity. Both gastric and duodenal lipolysis levels were similar to values reported in vivo and the rates of lipolysis were higher with LE-stabilized emulsions than with CA-stabilized emulsions (P < 0.05). TAG secretion by Caco-2 cells was found to be higher using (i) duodenal vs. gastric media (P < 0.001) and (ii) emulsions stabilized with CA vs. LE (P < 0.01). Consistently, gene expression of both FABP2 and FATP4 induced by the duodenal media was (i) higher than that with gastric media (P < 0.001) and (ii) faster than that with model mixed micelles. Using gastric media, TAG secretion of Caco-2 cells after 12 h was higher with RA than with OL (P < 0.001). Moreover, the RA-CA emulsion increased the size of secreted lipoprotein particles (514 nm vs. 61 to 130 nm; P < 0.01). In conclusion, it was possible to observe distinct responses in the lipid metabolism of Caco-2 cells incubated with lipolysis media obtained from different dietary emulsions digested by gastrointestinal lipases in vitro.

Behavior of almond oil bodies during in vitro gastric and intestinal digestion.

An aqueous suspension of almond oil bodies (about 10% lipids) was prepared and subjected to in vitro gastric (with pepsin) and intestinal (with bile salts and pancreatin) digestion, simulating fasting conditions. The physicochemical and structural changes of the almond oil body emulsion were examined. The almond oil body emulsion behaved similarly to a protein-stabilized emulsion, with flocculation of the oil bodies occurring under gastric conditions. Proteins, peptides, and phospholipids covered the surface of the oil bodies throughout gastric digestion. Under intestinal conditions, bile salts displaced the interfacial peptides and phospholipids, and disrupted the flocs. Gastric pepsinolysis of almond proteins was a prerequisite for their digestion in the duodenum. The oil body membrane had a negative impact on the efficiency of gastric digestion, and long chain fatty acids, the main lipolytic products, accumulated at the surface of the oil bodies and therefore limited the activity of pancreatic lipase.

Clinical characteristics of liver fibrosis in patients with choledochal cysts.

PURPOSE: The aim of the study was to identify the clinical characteristics and outcome of patients with liver fibrosis in choledochal cyst (CC). METHODS: Forty patients with CC who underwent liver biopsy were included. Liver fibrosis was classified as follows: grade 0, no fibrosis; grade 1, mild fibrosis localized in the portal area; grade 2, moderate fibrosis with occasional bridging; and grade 3, severe fibrosis with diffuse bridging. RESULTS: Fourteen patients (35%) had liver fibrosis. Patients in the fibrosis group were significantly younger (1.2 vs 2.7 years) and had higher total bilirubin (5.3 vs 2.6 mg/dL). Severity of liver fibrosis was inversely correlated with age (P = .044). Amylase and lipase in bile were significantly lower in the fibrosis group (amylase, 531 vs 15,000 U/L; lipase, 783 vs 23,100 U/L). Postoperative serum analysis demonstrated no differences between the two groups. Most patients in both groups had normal aspartate aminotransferase, alanine aminotransferase, total bilirubin, and γ-glutamyl transpeptidase regardless of severity of fibrosis. Postoperative biliary complication or cholangiocarcinoma was not found in the fibrosis group. CONCLUSIONS: Our data suggest that liver fibrosis is mainly influenced by obstructive cholangiopathy rather than refluxed pancreatic secretion. Prognosis of patients with CC and liver fibrosis was as good as that of patients without fibrosis.