Duodenal Fluid Research Articles

A quantification of gastric and duodenal fluid volumes in older adults using MRI

Older adults are an inherently heterogeneous population with various underlying pathologies, medication use, and habits. In this study, the variability of this population was studied for the gastric and duodenal fluid volumes, as the amount of gastrointestinal volumes could play an essential role in the dissolution of drugs. The fluid volumes were retrospectively quantified by using magnetic resonance imaging (MRI). In 265 included fasted older individuals, the gastric fluid volume was 28.9 ± 21.1 mL (arithmetic mean ± standard deviation). No significant covariate-effect on stomach fluid volume was observed for various medication use, pathologies, and habits (e.g. hypertension, smoking, proton-pump inhibitors (PPIs), and aspirin). The gastric fluid volume remained constant with increasing age and had a high variability. The volumes and the variability were, however, not higher than the gastric values reported in healthy younger adults. The duodenal fluid volume was 16.6 ± 10.0 mL and a slight but statistically significant decrease with age was seen. In addition, cystic pancreas, obesity, diuretics, and PPI use demonstrated a moderate but significant correlation with the duodenal fluid volume. The findings of this study could be considered when developing and testing new drug candidates for the older adult population. For example, the volumes including their variability could be used as an input in physiologically based pharmacokinetic modelling approaches to predict drug exposure in this population.

Grade IV gastric ulceration, pyloric aplasia, and an ectopic duodenal papilla in a 13-year-old Quarter Horse gelding evaluated for recurrent colic.

The objective of this Case Report was to describe the clinical manifestation and postmortem findings of a horse evaluated for recurrent colic diagnosed with pyloric aplasia and an ectopic duodenal papilla. 13-year-old Quarter Horse gelding. The horse was presented to a referral center for signs of colic that were unresponsive to management on the farm. No abnormalities were noted on rectal palpation; however, upon passage of a nasogastric tube, 31 L of net gastric reflux was obtained. Gastroscopy noted grade IV squamous ulceration and moderate glandular ulceration, severe gastric dilatation, an abnormally positioned gastric outflow tract, and an ectopic duodenal papilla leaking bile-like fluid directly into the stomach. The horse was initially treated with gastroprotectants, promotility agents, and dietary modifications. Following treatment failure and repeated episodes of colic with increasing severity, the horse was euthanized and a necropsy performed. At necropsy, it was confirmed that the aboral aspect of the stomach formed a dilated pouch and continued directly into the proximal duodenum with no discernible pyloric sphincter. The area of the pylorus was delineated by a faint indentation. The ectopic duodenal papilla was traced to the liver. Congenital gastric abnormalities, even in adult horses, should be considered as differential diagnoses when investigating horses presenting with a history of chronic colic. Neither pyloric aplasia nor an ectopic duodenal papilla have been described in the equine literature, and this Case Report raises awareness of the presence of such malformations and their manifestations.

Distinctive duodenal microbiomes and bile acid profiles in duodenal tumor patients revealed by prospective observational study

The incidence of duodenal tumors (DTs) is increasing. However, the mechanisms underlying its development remain unclear. Environmental factors, including the microbiome and bile acids (BAs), are believed to influence tumor development. Therefore, we conducted a single-center, prospective, observational study to investigate the potential differences between patients with DTs and healthy controls (HCs) based on these factors. In addition, the BAs in the duodenal fluid were measured using liquid chromatography-tandem mass spectrometry. We recruited 41 patients and performed 16S rRNA-seq. There was no difference in the observed ASVs or PCoA plot of Bray–Curtis dissimilarity between the DTs and HCs. The lithocholic acid concentration was significantly lower in the DT group than in the control group. The ratio of CDCA to LCA was significantly higher in patients with DTs. No significant differences in microbiota were observed between DTs and HCs. In patients with DTs, the lithocholic acid concentration in duodenal was significantly lower than in HCs.

Duodenal Fluid Analysis as a Rewarding Approach to Detect Low-Abundance Mutations in Biliopancreatic Cancers.

Diagnosis of biliopancreatic cancers by the available serum tumor markers, imaging, and histopathological tissue specimen examination remains a challenge. Circulating cell-free DNA derived from matched pairs of secretin-stimulated duodenal fluid (DF) and plasma from 10 patients with biliopancreatic diseases and 8 control subjects was analyzed using AmpliSeq™ HD technology for Ion Torrent Next-Generation Sequencing to evaluate the potential of liquid biopsy with DF in biliopancreatic cancers. The median cfDNA concentration was greater in DF-derived than in plasma-derived samples. A total of 13 variants were detected: 11 vs. 1 were exclusive for DF relative to the plasma source, and 1 was shared between the two body fluids. According to the four-tier systems, 10 clinical tier-I-II (76.9%), 1 tier-III (7.7%), and 2 tier-IV (15.4%) variants were identified. Notably, the 11 tier-I-III variants were exclusively found in DF-derived cfDNA from five patients with biliopancreatic cancers, and were detected in seven genes (KRAS, TP53, BRAF, CDKN2A, RNF43, GNAS, and PIK3CA); 82% of the tier-I-III variants had a low abundance, with a VAF < 6%. The mutational profiling of DF seems to be a reliable and promising tool for identifying cancer-associated alterations in malignant cancers of the biliopancreatic tract.

In situ interaction of pea peptides and bile salts under in vitro digestion: Potential impact on lipolysis

The present work evaluated how a native pea protein isolate (PPI) affects the key roles carried out by bile salts (BS) in lipid digestion by means of the in vitro static INFOGEST protocol. Two gastric residence times were evaluated (10 and 60 min), and then the peptides obtained (GPPP) were mixed with BS at physiological concentration in simulated intestinal fluid to understand how they interact with BS both at the bulk and at the interface. Both GPPP give rise to a film with a predominant viscous character that does not constitute a barrier to the penetration of BS, but interact with BS in the bulk duodenal fluid. When the peptides flushing from the stomach after the different gastric residence times undergo duodenal digestion, it was found that for the longer gastric residence time the percentage of soluble fraction in the duodenal phase, that perform synergistically with BS micelles, was twice that of the lower residence time, leading to an increase in the solubilization of oleic acid. These results finally lead to a greater extent of lipolysis of olive oil emulsions.This work demonstrates the usefulness of in vitro models as a starting point to study the influence of gastric residence time of pea protein on its interaction with BS, affecting lipolysis. Pea proteins were shown to be effective emulsifiers that synergistically perform with BS improving the release and bioaccessibility of bioactive lipids as olive oil.

The effect of lentinan on dexamethasone-induced immunosuppression in mice

The immune system acts as a vital defense barrier against pathogenic invasions, and its stable operation is crucial for maintaining body health. Nevertheless, various natural or artificial factors can compromise the body's immune function, leading to immunosuppression, which may interfere with the efficacy of vaccination and increase the susceptibility of the body to disease-causing pathogens. In an effort to ensure successful vaccinations and improve overall physical well-being, the search for appropriate immune regulators to enhance immunity is of paramount importance. Lentinan (LNT) has a significant role in immune regulation and vaccine adjuvants. In the present study, we constructed an immunosuppressive model using dexamethasone (DEX) and demonstrated that LNT could significantly improved antibody levels in immunosuppressive mice and stimulated T-lymphocyte proliferation and differentiation in intestinal Peyer's patches. LNT also increased the production of secretory immunoglobulin A (sIgA) in the duodenal fluid, the number of goblet cells, and the proportion of mucin area. Moreover, LNT modulated the intestinal microbiota and increased the production of short-chain fatty acids. Additionally, LNT promoted the proliferation, differentiation, and pro-inflammatory cytokines production of DEX-treated splenic T lymphocytes in vitro. Thus, the present study highlights the potential of LNT in reversing immunosuppression and avoiding the failure of vaccination.

MicroRNA-20a in extracellular vesicles derived from duodenal fluid is a possible biomarker for pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) has a high mortality rate owing to its late diagnosis and aggression. In addition, there are relatively few minimally invasive screening methods for the early detection of PDAC, making the identification of biomarkers for this disease a critical priority. Recent studies have reported that microRNAs in extracellular vesicles (EV-miRs) from bodily fluids can be useful for the diagnosis of PDACs. Given this, we designed this study to evaluate the utility of cancer EVs extracted from duodenal fluid (DF) and their resident EV-miRs as potential biomarkers for the detection of PDAC. EV-miRs were evaluated and identified in the supernatants of various pancreatic cancer cell lines (Panc-1, SUIT2, and MIAPaca2), human pancreatic duct epithelial cells, and the DF from patients with PDAC and healthy controls. EVs were extracted using ultracentrifugation and the relative expression of EV-miR-20a was quantified. We collected a total of 34 DF samples (27 PDAC patients and seven controls) for evaluation and our data suggest that the relative expression levels of EV-miR-20a were significantly higher in patients with PDAC than in controls (p = 0.0025). In addition, EV-miR-20a expression could discriminate PDAC from control patients regardless of the location of the tumor with an area under the curve values of 0.88 and 0.88, respectively. We confirmed the presence of EVs in the DF and suggest that the expression of EV-miR-20a in these samples may act as a potential diagnostic biomarker for PDAC.

Analysis of bile acid in saliva of patients with laryngopharyngeal reflux and non-laryngopharyngeal reflux

ABSTRACT — Background: Laryngopharyngeal reflux (LPR) is the backflow of gastric and or duodenal fluid into the larynx, pharynx, trachea, and bronchi. The prevalence of LPR is difficult to determine due to the limited gold standard and the large variety of LPR symptoms. Damage can occur due to the decrease in pH value and also because of exposure to harmful enzymes in reflux, including bile acid. Purpose : This study was conducted to analyze bile acid levels in the saliva of LPR patient and non LPR subject. Methods: This study is an observational study with a case-control design. The study was conducted in the ORL-HNS Department of Dr. M. Djamil Hospital, Padang, West Sumatra, Indonesia. The total sample size was 44 people. We enrolled 22 healthy subjects as the control group and 22 patients suspected of having LPR. Result: LPR patients are more common in women than in men, with 12 women and 10 men. Bile acid in the LPR group means of is 25.08±7.67µM, meanwhile, in the healthy group, the mean was 18.99±8.26 µM. There is a statistically significant in the incidence of LPR with the bile acids (p = 0.015) based on t- independent test. Conclusion: Our study confirmed that bile acids in saliva play a major role in diagnosing LPR.

Detection of gluten peptides in human duodenal fluids with immuno-liquid chromatography-mass spectrometry.

Gluten proteins are storage proteins in wheat that exhibit a certain resistance to gastrointestinal digestion. To explore solutions to cope with accidental ingestion of gluten in individuals suffering from gluten-related disorders, it is essential to monitor the fate of gluten peptides in biological samples, i.e., gastrointestinal juices, blood plasma or urine. In this work, we aimed at developing a mass spectrometry (MS)-based method for measuring gluten peptides in human duodenal fluids. Seven gluten peptides, including the well-documented 33-mer gluten peptide (LQLQPFPQPQLPYPQPQLPYPQPQLPYPQPQPF), were selected after a literature review and characterization of a gluten-containing product. Isotopically labelled peptides were used as references and a targeted liquid chromatography (LC) MS assay based on high resolution parallel reaction monitoring (PRM) was designed. Despite iterative and fine tuning of the LC-PRM-MS method, the low level of endogenous gluten peptides in human duodenal fluid samples precluded their direct detection. Thus, an initial immunoprecipitation (IP) step was included. Several antibodies were tested, and one proved reliable for the enrichment of the 33-mer gluten peptide as well as a few additional gluten peptides. Figures-of-merits of the immuno-LC-PRM-MS assay were assessed with a focus on quantification trueness and precision. We have developed an MS-based method for measuring the 33-mer gluten peptide in human duodenal fluids. Based on isotopic dilution, the method relies on the combination of IP and LC-PRM-MS analysis. Measurements were shown to be sensitive, quantitative, and reproducible.

Instant duodenal decompression after endoscopic retrograde cholangiopancreatography can effectively reduce the incidence of post-ERCP pancreatitis and hyperamylasemia.

Post-ERCP pancreatitis (PEP) is significantly influenced by the reflux of duodenal fluid. While gastrointestinal decompression represents a fundamental approach in acute pancreatitis management, the effectiveness of immediate duodenal decompression following ERCP to prevent PEP remains uncertain. This study aimed to investigate the impact of immediate duodenal decompression after ERCP on reducing the incidence of hyperamylasemia and PEP. This retrospective study encompassed patients with native papilla who underwent therapeutic ERCP for choledocholithiasis at the Department of Gastroenterology, Chun'an Branch of Zhejiang Provincial People's Hospital (Zhejiang, China) between January 2020 and June 2023. Based on the immediate placement of a duodenal decompression tube post-ERCP, patients were categorized into two groups: the duodenal decompression group and the conventional procedure group. Primary outcomes included the incidence of PEP and hyperamylasemia. A total of 195 patients were enrolled (94 in the duodenal decompression group and 101 in the conventional procedure group). Baseline clinical and procedural characteristics exhibited no significant differences between the two groups. PEP occurred in 2 patients (2.1%) in the duodenal decompression group, in contrast to 11 patients (10.9%) in the conventional procedure group (Risk difference [RD] 8.8%; 95% confidence interval [CI] 1.7%-16.5%, P = 0.014). Hyperamylasemia was observed in 8 patients (8.5%) in the duodenal decompression group, compared to 20 patients (19.8%) in the conventional procedure group (RD 11.3%; 95% CI 1.4%-21.0%; P = 0.025). Patients with PEP in both groups showed improvement after receiving active treatment. No severe cases of PEP occurred in either group, and no serious adverse events related to duodenal catheter decompression were reported. Immediate duodenal decompression following ERCP demonstrates an effective reduction in the incidence of hyperamylasemia and PEP.

Development of a molecular barcode detection system for pancreaticobiliary malignancies and comparison with next-generation sequencing

BackgroundObtaining sufficient tumor tissue for genomic profiling is challenging in pancreaticobiliary cancer (PBCA). We determined the utility of molecular barcoding (MB) of liquid biopsies (bile, duodenal fluid, and plasma) for highly sensitive genomic diagnosis and detection of druggable mutations for PBCA. MethodsTwo in-house panels of 60 genes (non-MB panel) and 21 genes using MB (MB panel) were used for the genomic analysis of 112 DNA samples from 20 PBCA patients. We measured the yield of DNA and compared the genomic profiles of liquid samples obtained using the non-MB panel and the MB panel. The utility of the panels in detecting druggable mutations was investigated. ResultsA significantly greater amount of DNA was obtained from bile supernatants and precipitates compared to tumor samples (P < 0.001 and P = 0.001, respectively). The number of mutations per patient was significantly higher using the MB panel than using the non-MB panel (2.8 vs. 1.3, P = 0.002). Tumor-derived mutations were detected more frequently using the MB panel than the non-MB panel (P = 0.023). Five drug-matched mutations were detected in liquid samples. ConclusionsLiquid biopsy with MB may have utility in providing genomic information for the prognosis of patients with PBCA.

EGS P23 A rare case of gallstone ileus post Roux-en-Y Gastric Bypass: Stone migration from large duodenal diverticulum

Abstract Background Small bowel obstruction following Roux-en-Y gastric bypass is common and is mainly attributed to adhesions or internal herniation. Intraluminal formation of stones, usually in areas of stasis due to the anatomical changes post-RYGB, and migration to the distal ileum to cause acute bowel obstruction is rare. Impacted stones at the duodenal diverticulum can trigger diverticular inflammation, back pressure to the common bile duct and pancreas resulting in abdominal pain, nausea and vomiting, intermittent derangement of liver enzymes and episodes of cholangitis and pancreatitis. The impaction at the distal ileum is an emergency requiring prompt diagnosis and intervention to prevent complications. Methods This is a case report of a 56-year-old female who presented at East Surrey Hospital in February 2023 with recurrent upper abdominal pain, nausea and vomiting. She previously underwent an open cholecystectomy for cholelithiasis and cholecystoduodenal fistula (2003) and a Roux-en-Y gastric bypass (2018). Her symptoms were initially thought to be secondary to inflammation and periduodenal abscess managed with antibiotics, but as time and scans (CT, MRCP, water-soluble contrast, gastroscopy) progressed without resolution of her symptoms it became evident that she had developed mechanical bowel obstruction. We described her case and the diagnostic challenges leading to the final surgical management. Results To investigate the patient’s symptoms, her intermittently raised inflammatory markers, deranged liver enzymes and amylase a series of radiological examinations was rperformed. Initial CT scan showed an inflamed large duodenal (D3) diverticulum and fluid filled proximal duodenum. Subsequent MRCP demonstrated dilated common bile duct and intrahepatic ducts without any ductal stone. Repeat CT scan two weeks later, confirmed small bowel obstruction due to a heterogenous bolus at the ileocecal valve with resolution of the duodenal inflammation and dilatation. The patient underwent a laparoscopic extraction of a stone impacted at the ileocecal valve causing small bowel obstruction and recovered well. Conclusions Even though small bowel obstruction due to stone aggregation is uncommon post-RYGB, a high index of suspicion for the diagnosis and a low threshold for early laparoscopic intervention can prevent further serious complications. Reporting these cases in literature offers a guidance for the workup and management of these unusual scenarios amongst surgical teams and improves patients’ outcomes.

Current status of molecular diagnostic approaches using liquid biopsy

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive and lethal cancers, and developing an efficient and reliable approach for its early-stage diagnosis is urgently needed. Precancerous lesions of PDAC, such as pancreatic intraepithelial neoplasia (PanIN) and intraductal papillary mucinous neoplasms (IPMN), arise through multiple steps of driver gene alterations in KRAS, TP53, CDKN2A, SMAD4, or GNAS. Hallmark mutations play a role in tumor initiation and progression, and their detection in bodily fluids is crucial for diagnosis. Recently, liquid biopsy has gained attention as an approach to complement pathological diagnosis, and in addition to mutation signatures in cell-free DNA, cell-free RNA, and extracellular vesicles have been investigated as potential diagnostic and prognostic markers. Integrating such molecular information to revise the diagnostic criteria for pancreatic cancer can enable a better understanding of the pathogenesis underlying inter-patient heterogeneity, such as sensitivity to chemotherapy and disease outcomes. This review discusses the current diagnostic approaches and clinical applications of genetic analysis in pancreatic cancer and diagnostic attempts by liquid biopsy and molecular analyses using pancreatic juice, duodenal fluid, and blood samples. Emerging knowledge in the rapidly advancing liquid biopsy field is promising for molecular profiling and diagnosing pancreatic diseases with significant diversity.

Differential diagnosis of neonatal cholestasis by genetic testing: A case report

Alagille syndrome (ALGS) is a cholestasis disorder with multiple organ dysfunction, including heart and kidney. The causative genes of ALGS are JAG1 and NOTCH2. Dysregulation of Notch signaling leads to defects in the developmental mechanisms of the bile ducts. Sometimes extrahepatic bile duct hypoplasia makes it difficult to differentiate ALGS from biliary atresia. The Kasai procedure for ALGS is associated with poor liver and patient outcomes. Therefore, it is important to differentiate ALGS from biliary atresia correctly. A 2-day-old female neonate was admitted to the neonatal intensive care unit due to poor feeding; blood tests on day 7 showed elevated direct bilirubin and total bile acids. Right hydronephrosis, peripheral pulmonary artery stenosis, butterfly vertebra, and posterior embryotoxon were observed, and ALGS was suspected from these findings. Duodenal fluid tests and biliary scintigraphy showed no bile excretion from the liver into the intestinal tract. These findings suggested biliary atresia, and to distinguish ALGS from biliary atresia, rapid JAG1 and NOTCH2 sequencing was performed preoperatively. We found a heterozygous de novo single nucleotide insertion mutation c.192dupC p.(Lys65GlnfsX8). Operative cholangiography showed that the common bile duct was patent, but the common hepatic duct was barely open, a finding consistent with type III-a-o biliary atresia. Because of the preoperative diagnosis of ALGS, Kasai procedure was omitted. Neonates and early infants with cholestasis with extrahepatic symptoms should be carefully examined, with genetic syndromes and biliary atresia considered differential diagnoses. Advances in genetic analysis methods are expected to facilitate early diagnosis of ALGS.

Characterization of Aspirated Duodenal Fluids from Parkinson's Disease Patients.

Parkinson's disease, one of the most common neurodegenerative diseases, may not only affect the motor system, but also the physiology of the gastrointestinal tract. Delayed gastric emptying, impaired motility and altered intestinal bacteria are well-established consequences of the disease, which can have a pronounced effect on the absorption of orally administered drugs. In contrast, no studies have been performed into the composition of intestinal fluids. It is not unlikely that Parkinson's disease also affects the composition of intestinal fluids, a critical factor in the in vitro and in silico simulation of drug dissolution, solubilization and absorption. In the current study, duodenal fluids were aspirated from Parkinson's disease (PD) patients and age-matched healthy controls (healthy controls, HC) consecutively in fasted and fed conditions. The fluids were then characterized for pH, buffer capacity, osmolality, total protein, phospholipids, bile salts, cholesterol and lipids. In a fasted state, the intestinal fluid composition was highly similar in PD patients and healthy controls. In general, the same was true for fed-state fluids, apart from a slightly slower and less pronounced initial change in factors directly affected by the meal (i.e., buffer capacity, osmolality, total protein and lipids) in PD patients. The absence of a fast initial increase for these factors immediately after meal intake, as was observed in healthy controls, might result from slower gastric emptying in PD patients. Irrespective of the prandial state, a higher relative amount of secondary bile salts was observed in PD patients, potentially indicating altered intestinal bacterial metabolism. Overall, the data from this study indicate that only minor disease-specific adjustments in small intestinal fluid composition should be considered when simulating intestinal drug absorption in PD patients.

Prevalence of Small Intestinal Bacterial Overgrowth Syndrome in Patients with Non-Alcoholic Fatty Liver Disease/Non-Alcoholic Steatohepatitis: A Cross-Sectional Study.

Non-alcoholic fatty liver disease (NAFLD) is a multifactorial, wide-spectrum liver disorder. Small intestinal bacterial overgrowth (SIBO) is characterized by an increase in the number and/or type of colonic bacteria in the upper gastrointestinal tract. SIBO, through energy salvage and induction of inflammation, may be a pathophysiological factor for NAFLD development and progression. Consecutive patients with histological, biochemical, or radiological diagnosis of any stage of NAFLD (non-alcoholic fatty liver [NAFL], non-alcoholic steatohepatitis [NASH], cirrhosis) underwent upper gastrointestinal endoscopy. Duodenal fluid (2cc) was aspirated from the 3rd-4th part of duodenum into sterile containers. SIBO was defined as ≥103 aerobic colony-forming units (CFU)/mL of duodenal aspirate and/or the presence of colonic-type bacteria. Patients without any liver disease undergoing gastroscopy due to gastroesophageal reflux disease (GERD) comprised the healthy control (HC) group. Concentrations (pg/mL) of tumor necrosis factor alpha (TNFα), interleukin (IL)-1β, and IL-6 were also measured in the duodenal fluid. The primary endpoint was to evaluate the prevalence of SIBO in NAFLD patients, while the comparison of SIBO prevalence among NAFLD patients and healthy controls was a secondary endpoint. We enrolled 125 patients (51 NAFL, 27 NASH, 17 cirrhosis, and 30 HC) aged 54 ± 11.9 years and with a weight of 88.3 ± 19.6 kg (NAFLD vs. HC 90.7 ± 19.1 vs. 80.8 ± 19.6 kg, p = 0.02). Overall, SIBO was diagnosed in 23/125 (18.4%) patients, with Gram-negative bacteria being the predominant species (19/23; 82.6%). SIBO prevalence was higher in the NAFLD cohort compared to HC (22/95; 23.2% vs. 1/30; 3.3%, p = 0.014). Patients with NASH had higher SIBO prevalence (6/27; 22.2%) compared to NAFL individuals (8/51; 15.7%), but this difference did not reach statistical significance (p = 0.11). Patients with NASH-associated cirrhosis had a higher SIBO prevalence compared to patients with NAFL (8/17; 47.1% vs. 8/51; 15.7%, p = 0.02), while SIBO prevalence between patients with NASH-associated cirrhosis and NASH was not statistically different (8/17; 47.1% vs. 6/27; 22.2%, p = 0.11). Mean concentration of TNF-α, IL-1β, and IL-6 did not differ among the different groups. The prevalence of SIBO is significantly higher in a cohort of patients with NAFLD compared to healthy controls. Moreover, SIBO is more prevalent in patients with NASH-associated cirrhosis compared to patients with NAFL.

Factors that influence the pancreatic and duodenal microbiome in patients undergoing pancreatic surgery.

This study examined the correlation between pancreatic microbiome and patients characteristics. Furthermore, we compared different duodenal materials to examine their reflection of the pancreatic microbiome. Patients undergoing pancreatic surgery were included in the study. Characteristics of those patients were prospectively registered and sterile pancreatic biopsies were collected during surgery. After completion of the resection, duodenal fluid, -tissue and -swab were collected. Bacterial DNA was extracted and analyzed with IS-pro assay. Paired samples of 51 patients were available for evaluation, including pancreatic biopsies from all patients, 22 duodenal fluids, 21 duodenal swabs and 11 duodenal tissues. The pancreatic microbiome consisted mostly of Proteobacteria followed by Firmicutes, Actinobacteria, Fusobacteria and Verrucomicrobia (FAFV) and Bacteroidetes. On species level, Enterococcus faecalis, Escherichia coli, and Enterobacter-Klebsiella were most abundant. In pancreatic biopsies, the total bacterial load and Proteobacteria load were significantly higher in patients with biliary drainage (54618.0 vs 5623.5; 9119.0 vs 2067.1). Patients who used proton pump inhibitors had a significantly higher total bacterial load (115964.7 vs 8495.8), more FAFV (66862.9 vs 1890.1), more Proteobacteria (24245.9 vs 2951.4) and more Bacteroidetes (542.5 vs 25.8). The head of the pancreas contained significantly more bacteria (21193.4 vs 2096.8) and more FAFV (5225.7 vs 19.0) compared to the tail, regardless of biliary drainage. Furthermore, the microbiome of all duodenal materials showed a weak correlation with the pancreatic microbiome. Biliary drainage, use of proton pump inhibitors, and anatomic location of the pancreatic biopsy influence the pancreatic microbiome. Furthermore, the duodenal microbiome does not suffice as a surrogate for the pancreatic microbiome.

Abstract PR013: High sensitive mutation detection in liquid biopsy with duodenal fluid captures genetic mutations associated with pancreatic carcinogenesis

Abstract Background: Blood-based liquid biopsy for comprehensive genomic profiling is available for cancer patients; however, given the limited amount of tumor-derived DNA in plasma, it remained challenging to detect pancreatic ductal adenocarcinoma (PDA) at earlier stages. Here, we evaluated the mutation detection in DNA from the duodenal fluid as an alternative biospecimen obtained by a less-invasive approach relative to endoscopic biopsy. Methods: In 300 patients of PDA, IPMN, or other pancreatic diseases in seven institutions, we collected duodenal fluid containing pancreatic juice from the duodenal lumen through the endoscopic channel. Plasma was also collected, and DNA was extracted from both samples, and molecular barcode sequencing, which enabled the highly sensitive detection of low- frequent mutation, targeting five pancreatic cancer-associated genes, namely, KRAS, GNAS, TP53, CDKN2A, and SMAD4, were performed. Detected mutations were evaluated for concordance with surgically resected tissue or needle biopsy. Results: DNA extracted from the duodenal fluids (DFDNA) had a much higher yield (avg. 25.4 ng/ml) than plasma cell-free DNA (avg. 1.3 ng/ml). While plasma cfDNA had a typical fragmentation pattern with a peak at 160 bp, DFDNA has a variety of fragmentation patterns. Hotspot mutations detected in the duodenal fluids showed as much as 51.4% concordance with a 0.2 % the limit of detection (LOD) for its variant allele frequency in PDA-associated mutations in the DFDNA (n=109) with the mutations in PDA lesion, whereas only 25% concordance with 0.4% LOD in the plasma cfDNA (n=104). In contrast to plasma cfDNA, where liquid-tissue matches were limited to advanced stages of cancer, DFDNA assay enabled the higher concordance through a wide range of PDA stages, even Stage 0 (83.3%) or I (45.5%) UICC 8th, or IPMN cases, and allowed to detect of additional mutations that were originated from multicentric/concomitant lesions in the pancreas. Conclusions: Duodenal fluid-derived DNA can be a potent biospecimen to detect mutations with higher yield and sensitivity than plasma cfDNA. Although validation of the duodenal fluid collection and methods up to more sensitive analysis is required to meet the standards of practical testing, it has the potential to detect fast-stage pancreatic disease and the detection of lesions that were not visible on pathological images and is expected to lead to the implementation of highly sensitive liquid biopsy. Citation Format: Yusuke Ono, Kenji Takahashi, Hidenori Karasaki, Yusuke Mizukami. High sensitive mutation detection in liquid biopsy with duodenal fluid captures genetic mutations associated with pancreatic carcinogenesis [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr PR013.

Molecular Dynamics Simulations of Self-Assembling Colloids in Fed-State Human Intestinal Fluids and Their Solubilization of Lipophilic Drugs.

Bioavailability of oral drugs often depends on how soluble the active pharmaceutical ingredient is in the fluid present in the small intestine. For efficient drug discovery and development, computational tools are needed for estimating this drug solubility. In this paper, we examined human intestinal fluids collected in the fed state, with coarse-grained molecular dynamics simulations. The experimentally obtained concentrations in aspirated duodenal fluids from five healthy individuals were used in three simulation sets to evaluate the importance of the initial distribution of molecules and the presence of glycerides in the simulation box when simulating the colloidal environment of the human intestinal fluid. We observed self-assembly of colloidal structures of different types: prolate, elongated, and oblate micelles, and vesicles. Glycerides were important for the formation of vesicles, and their absence was shown to induce elongated micelles. We then simulated the impact of digestion and absorption on the different colloidal types. Finally, we looked at the solubilization of three model compounds of increasing lipophilicity (prednisolone, fenofibrate, and probucol) by calculating contact ratios of drug-colloid to drug-water. Our simulation results of colloidal interactions with APIs were in line with experimental solubilization data but showed a dissimilarity to solubility values when comparing fasted-/fed-state ratios between two of the APIs. This work shows that coarse-grained molecular dynamics simulation is a promising tool for investigation of the intestinal fluids, in terms of colloidal attributes and drug solubility.

Glyphosate detection in the duodenal fluid of horses with gastric ulcer syndrome

The hay producing plants, concentrate, straw and meadows could be contaminated by the aerosols of glyphosate based herbicide during spraying process of crops and pre-harvest desiccation treatment of cereals. The aim of this study is to investigate the concentration of glyphosate in the duodenal fluid of horses with gastric ulcer syndrome. The stomach and duodenum of referred untreated horse patients (n=92) with colic, weight loss, diarrhoea, anemia or performance intolerance were endoscopically examined right after the admission. Duodenal fluid (40 ml) was collected from the duodenal region where the papilla duodeni major is located. Hematology and clinical chemistry data were examined. The concentration of glyphosate in serum and duodenal fluid samples were analysed using a competitive ELISA and control analysis had also been done with HPLC. Statistical differences between groups were determined by the non-parametric Mann-Whitney-test using a significant level of p≤0,05. Glyphosate was detected in all duodenal fluid (median 12,2 ng/ml; 1st quartile 4,0 ng/ml; 3rd quartile 19,3 ng/ml; min 0,6 ng/ml; max. 192,9 ng/ml) and blood samples (1,79 ng/ml; 1,0 ng/ml; 2,8 ng/ml; 0,2 ng/ml; 3,7 ng/ml) of all horses. Glyphosate concentrations of duodenal fluid samples are significantly higher than in blood samples (Mann Whitney U-test, p≤0,05). The concentration of glyphosate in the duodenal fluid was significantly higher in horses with squamous gastric disease (grade 4/4; n=11/92) compared to horses with normal squamous mucosa (grade 0/4, n=10/92) (median: 19,8 ng/ml versus 8,4 ng/ml). Horses with glandular gastric disease and a grade 4/4 (n=9/92) had higher concentrations of glyphosate in the duodenal fluid than horses with normal glandular mucosa (grade 0/4; n=9/92) (median: 19,2 versus 11,1). The Gamma-Glutamyltransferase (GGT) enzyme activity is significantly higher in the group of horses with lower concentration of glyphosate in the duodenal fluid (≤12,2 ng/ml) compared with the group with higher concentration of glyphosate (>12,2 ng/ml) (median 279,5 versus 101,9 U/L). During autumn the horses had higher concentrations of glyphosate in duodenal fluid (n=18; median 14,3) compared with lower concentrations in spring time (n=34; median 8,1 ng/ml). Horses kept around big cities had significantly higher concentrations of glyphosate in the duodenal fluid in comparison to horses living in the countryside (medians 17,8 ng/ml versus 7,5 ng/ml).