Publications by authors named "Vonlaufen A"

Background: Colonoscopies, are vital for initial screening, follow-ups, surveillance of neoplasia, and assessing symptoms like rectal bleeding. Successful colonoscopies require thorough colon preparation, but up to 25% fail due to poor preparation. This can lead to longer procedures, repeat colonoscopies, inconvenience, poorer health outcomes, and higher costs.

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Most cancer deaths result from metastasis, which is the dissemination of cells from a primary tumor to distant organs. Metastasis involves changes to molecules that are essential for tumor cell adhesion to the extracellular matrix and to endothelial cells. Junctional Adhesion Molecule C (JAM-C) localizes at intercellular junctions as homodimers or more affine heterodimers with JAM-B.

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Background And Study Aims: Upper gastrointestinal (UGI) bleeding is a frequent cause of hospitalization. Its severity may be assessed before endoscopy using the Glasgow-Blatchford Bleeding Score (GBS), a score validated to identify patients requiring clinical intervention. The aim of this study was to assess whether the GBS was effective for shortening hospital stay and reducing costs in patients with an UGI bleeding predicted at low risk of requiring clinical intervention.

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Background: Acute pancreatitis is characterized by inflammatory processes affecting not only the pancreas, but also the lung. Here, we investigated timing of leucocyte infiltration and chemokine expression within lung and pancreas during pancreatitis and whether treatments selectively inhibiting chemokines (using Evasins) could improve organ injury.

Material And Methods: C57Bl/6 mice were submitted in vivo to 10-h intraperitoneal injections of cerulein and followed for up to 168 h.

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Alcohol is a major cause of chronic pancreatitis. About 5% of alcoholics will ever suffer from pancreatitis, suggesting that additional co-factors are required to trigger an overt disease. Experimental work has implicated lipopolysaccharide, from gut-derived bacteria, as a potential co-factor of alcoholic pancreatitis.

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Colorectal cancer is Europe's most frequent malignancy with an annual incidence of more than 430000 cases and a mortality approaching 50%. Fecal blood tests (guaiac fecal occult blood tests, fecal immunological tests) are primarily designed for early cancer detection. They lack sensitivity and have to be repeated annually to be effective.

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Background/aims: During acute pancreatitis, tumor necrosis factor (TNF)-α, interleukin (IL)-1 and IL-6 play a pivotal role in promoting injury in the pancreas and remote organs. IL- 18 is a more recently discovered proinflammatory cytokine whose expression is also increased in serum. However, the profile of IL-18 expression in the pancreas and lung is unknown, and the aim of our study was to investigate such expression in rats with pancreatitis.

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Autoimmune pancreatitis (ALP) represents a distinct form of chronic pancreatitis initially described in Japan but now reported worldwide. AIP often presents with obstructive jaundice/pancreatic mass as well as pancreatic exocrine and endocrine insufficiency. Histologically, it is characterised by a lymphoplasmacytic infiltrate with fibrosis.

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Pancreatic stellate cells (PSCs) produce the stromal reaction in pancreatic cancer (PC), and their interaction with cancer cells facilitates cancer progression. This study investigated the role of human PSCs (hPSCs) in the metastatic process and tumor angiogenesis using both in vivo (orthotopic model) and in vitro (cultured PSC and PC cells) approaches. A sex mismatch study (injection of male hPSCs plus female PC cells into the pancreas of female mice) was conducted to determine whether hPSCs accompany cancer cells to metastatic sites.

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Background And Aims: Administration of repeated lipopolysaccharide (LPS) injections in alcohol-fed rats leads to significant pancreatic injury including fibrosis. However, it remains unknown whether alcoholic (chronic) pancreatitis has the potential to regress when alcohol is withdrawn. The aims of the study were (1) to compare the effect of alcohol withdrawal/continuation on pancreatic acute injury and fibrosis; and (2) to assess the effects of alcohol ± LPS on pancreatic stellate cell (PSC) apoptosis in vivo and in vitro.

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The pancreatic secretagogue cholecystokinin (CCK) is widely thought to stimulate enzyme secretion by acinar cells indirectly via activation of the vagus nerve. We postulate an alternative pathway for CCK-induced pancreatic secretion. We hypothesize that neurally related pancreatic stellate cells (PSCs; located in close proximity to the basolateral aspect of acinar cells) play a regulatory role in pancreatic secretion by serving as an intermediate target for CCK and secreting the neurotransmitter acetylcholine (ACh), which, in turn, stimulates acinar enzyme secretion.

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Background: Pancreatic stellate cells (PSCs) play a critical role in pancreatic fibrosis. To date, human PSC biology has been studied using cancer- or inflammation-associated (pre-activated) PSCs, but an in vitro model of quiescent normal human PSCs (NhPSCs) has been lacking.

Aims: To (i) isolate and characterize quiescent NhPSCs, and (ii) evaluate the response of culture-activated NhPSCs to cytokines and LPS.

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Alcohol is recognized as a direct hepatotoxin, but the precise molecular pathways that are important for the initiation and progression of alcohol-induced tissue injury are not completely understood. The current understanding of alcohol toxicity to organs suggests that alcohol initiates injury by generation of oxidative and nonoxidative ethanol metabolites and via translocation of gut-derived endotoxin. These processes lead to cellular injury and stimulation of the inflammatory responses mediated through a variety of molecules.

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Pancreatitis (necroinflammation of the pancreas) has both acute and chronic manifestations. Gallstones are the major cause of acute pancreatitis, whereas alcohol is associated with acute as well as chronic forms of the disease. Cases of true idiopathic pancreatitis are steadily diminishing as more genetic causes of the disease are discovered.

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Pancreatic cancer--a tumor displaying a particularly abundant stromal reaction--is notorious for its poor prognosis. Recent studies, via newly developed orthotopic models, provide compelling evidence of an important role for pancreatic stellate cells (PSC) in pancreatic cancer progression. Characterization of the mechanisms mediating PSC-cancer interactions will lead to the development of much needed alternative therapeutic approaches to improve disease outcome.

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Pancreatic stellate cells (PSC) produce the stromal reaction in pancreatic cancer, but their role in cancer progression is not fully elucidated. We examined the influence of PSCs on pancreatic cancer growth using (a) an orthotopic model of pancreatic cancer and (b) cultured human PSCs (hPSC) and human pancreatic cancer cell lines MiaPaCa-2 and Panc-1. Athymic mice received an intrapancreatic injection of saline, hPSCs, MiaPaCa-2 cells, or hPSCs + MiaPaCa-2.

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Background & Aims: This study examined the possible role of endotoxinemia (from increased gut permeability) as an additional trigger factor for overt pancreatic disease and as a promoter of chronic pancreatic injury in alcoholics by using a rat model of chronic alcohol feeding and in vitro experiments with cultured pancreatic stellate cells (PSCs), the key mediators of pancreatic fibrosis.

Methods: In the in vivo model, Sprague-Dawley rats fed isocaloric Lieber-DeCarli liquid diets +/- alcohol for 10 weeks were challenged with a single dose or 3 repeated doses of the endotoxin lipopolysaccharide (LPS) and the pancreas was examined. In the in vitro studies, rat PSCs were assessed for activation on exposure to LPS +/- ethanol.

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Drug-induced pancreatitis represents 2% of acute pancreatitis. The incidence is rising with more than 260 substances that have been incriminated so far. The important steps for the diagnosis are the exclusion of the other causes of acute pancreatitis, the chronology between the introduction of the drug, the appearance of the symptoms and the resolution of the complaints and the elevation of pancreatic enzymes after discontinuation of the treatment as well as the documentation in the literature of similar cases.

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The infiltration of inflammatory cells into the pancreas is an early and central event in acute pancreatitis that promotes local injury and systemic complications of the disease. Recent research has yielded the important finding that resident cells of the pancreas (particularly acinar and pancreatic stellate cells) play a dynamic role in leukocyte attraction via secretion of chemokines and cytokines and expression of adhesion molecules. Significant progress has been made in recent years in our understanding of the role of leukocyte movement (adhesion to the blood vessel wall, transmigration through the blood vessel wall and infiltration into the parenchyma) in the pathophysiology of acute pancreatitis.

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Alcohol abuse is the major cause of chronic inflammation of the pancreas (i.e., chronic pancreatitis).

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We review developments in five areas of therapeutic endoscopic retrograde cholangiopancreatography (ERCP) and management of pancreatic tumors during the period September 2005-August 2006. First, in the management of painful chronic pancreatitis, the use of multiple plastic stents for aggressive dilation of strictures located in the head of the pancreas has been put forward to resolve two significant issues associated with current techniques, i. e.

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We hypothesized that the function of both sinusoidal and canalicular transporters importantly controls the concentrations of organic anions within normal hepatocytes. Consequently, we investigated how acute transport regulation of the sinusoidal organic anion transporting polypeptides (Oatps) and the canalicular multidrug resistance associated protein 2 (Mrp(2)) determines the hepatic concentrations of the organic anion gadolinium benzyloxypropionictetraacetate (BOPTA) in rat livers. Livers were perfused with labeled BOPTA in different experimental settings that modify the function of Oatps and Mrp(2) through the protein kinase C (PKC) pathway.

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Background: Barrett's esophagus, a risk factor for esophageal adenocarcinoma, is associated with reflux disease. The aim of this study was to assess the expression of bile acid receptors in the esophagus (normal, esophagitis, Barrett's esophagus and adenocarcinoma) and to investigate their possible function.

Results: the expression of the bile acid receptors FXR and VDR in esophageal biopsies from patients with a normal mucosa, esophagitis, Barrett's esophagus or adenocarcinoma (n = 6 per group) and in cell lines derived from Barrett's esophagus and esophageal adenocarcinoma, was assessed by real time Q-PCR and immunohistochemistry.

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The recruitment of inflammatory cells contributes significantly to tissue injury in acute pancreatitis. This process implies several molecular interactions between circulating and endothelial cells. The adhesion molecule junctional adhesion molecule C (JAM-C) is involved in leukocyte transendothelial migration and it can form homophilic (JAM-C/JAM-C) and heterophilic interactions with the leukocyte integrin alpha(M)beta(2).

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