This review encompasses the most important advances in liver functions and hepatotoxicity and analyzes which mechanisms can be studied in vitro. In a complex architecture of nested, zonated lobules, the liver consists of approximately 80 % hepatocytes and 20 % non-parenchymal cells, the latter being involved in a secondary phase that may dramatically aggravate the initial damage. Hepatotoxicity, as well as hepatic metabolism, is controlled by a set of nuclear receptors (including PXR, CAR, HNF-4α, FXR, LXR, SHP, VDR and PPAR) and signaling pathways. When isolating liver cells, some pathways are activated, e.g., the RAS/MEK/ERK pathway, whereas others are silenced (e.g. HNF-4α), resulting in up- and downregulation of hundreds of genes. An understanding of these changes is crucial for a correct interpretation of in vitro data. The possibilities and limitations of the most useful liver in vitro systems are summarized, including three-dimensional culture techniques, co-cultures with non-parenchymal cells, hepatospheres, precision cut liver slices and the isolated perfused liver. Also discussed is how closely hepatoma, stem cell and iPS cell–derived hepatocyte-like-cells resemble real hepatocytes. Finally, a summary is given of the state of the art of liver in vitro and mathematical modeling systems that are currently used in the pharmaceutical industry with an emphasis on drug metabolism, prediction of clearance, drug interaction, transporter studies and hepatotoxicity. One key message is that despite our enthusiasm for in vitro systems, we must never lose sight of the in vivo situation. Although hepatocytes have been isolated for decades, the hunt for relevant alternative systems has only just begun.Electronic supplementary materialThe online version of this article (doi:10.1007/s00204-013-1078-5) contains supplementary material, which is available to authorized users.

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The incidence, clinical presentation, therapeutic options, and outcome of hepatic artery thrombosis (HAT) were analyzed in a series of 1,192 consecutive adult orthotopic liver transplantations (OLTs). HAT after OLT was observed in 30 cases, resulting in an incidence of 2.5%. The incidence of HAT increased 5.76-fold when the donor hepatic artery was reconstructed with an interposition graft to the supraceliac aorta (P <.05). Early HAT (within the first 30 days after OLT) occurred in 14 of these patients (46.7%), whereas in 16 patients (53.3%), HAT occurred beyond 30 days post-OLT. Clinical presentation of HAT ranged from an increase in serum transaminase levels with or without cholestasis to liver abscess and biliary complications, including cholangitis, bile duct stenosis or necrosis, to liver dysfunction and failure. Impairment of graft function was observed in patients with early HAT, whereas biliary tract destruction was seen more often in patients with late HAT. In only 1 patient was HAT clinically asymptomatic. Therapy consisted of recombinant plasminogen lysis with hepaticojejunostomy, liver abscess drainage, endoscopy or surveillance, and surgical thrombectomy. In 14 of 30 patients (46.7%), the occurrence of HAT required re-OLT. Nine patients with HAT died during follow-up; however, only 4 of these deaths were related to HAT, resulting in a mortality rate of 13.3%. Our results indicate that HAT is a rare but serious complication after OLT, requiring re-OLT in almost 50% of patients. In particular, conservative treatment modalities may significantly prolong graft survival, thus postponing re-OLT.

Complications involving the portal vein or the vena cava, are rare after orthotopic liver transplantation. We report on the incidence and treatment of venous complications following 1000 orthotopic liver transplantations in 911 patients. Twenty-six of the adult patients (2.7%) suffered from portal complications after transplantation, whereas complications of the vena cava were observed in only 17 patients (1.8%). Technical problems or recurrence of the underlying disease (e.g. Budd-Chiari syndrome) accounted for the majority of complications of the vena cava, whereas alteration of the vessel wall or splenectomy during transplantation could be identified as important risk factors for portal vein complications. In patients undergoing modification of the standard end-to-end veno-venous anastomosis of the portal vein due to pathological changes of the vessel wall, complications occurred in 8.3%, whereas only 2.4% of patients who received a standard anastomosis of the portal vein experienced complications of the portal vein. Furthermore, splenectomy during transplantation was also associated with an increased incidence of portal vein complications (10.5 vs. 2.2% in patients without splenectomy). Treatment was dependent on the signs and symptoms of the patients, and varied considerably between patients with portal vein complications and patients suffering from complications of the vena cava. Complications of the vena cava led to retransplantation in about one-third of the patients, whereas in patients with occlusion of the portal vein, retransplantation was necessary in only 15%, and more than half of the patients suffering from portal vein complications did not require any treatment at all. Usually, treatment of patients with portal vein complications only became necessary when additional complications such as arterial occlusion or bile duct injuries occurred.

Background and aimsHelicobacter pylori is the causative agent of gastric diseases and the main risk factor in the development of gastric adenocarcinoma. In vitro studies with this bacterial pathogen largely rely on the use of transformed cell lines as infection model. However, this approach is intrinsically artificial and especially inappropriate when it comes to investigating the mechanisms of cancerogenesis. Moreover, common cell lines are often defective in crucial signalling pathways relevant to infection and cancer. A long-lived primary cell system would be preferable in order to better approximate the human in vivo situation.MethodsGastric glands were isolated from healthy human stomach tissue and grown in Matrigel containing media supplemented with various growth factors, developmental regulators and apoptosis inhibitors to generate long-lasting normal epithelial cell cultures.ResultsCulture conditions were developed which support the formation and quasi-indefinite growth of three dimensional (3D) spheroids derived from various sites of the human stomach. Spheroids could be differentiated to gastric organoids after withdrawal of Wnt3A and R-spondin1 from the medium. The 3D cultures exhibit typical morphological features of human stomach tissue. Transfer of sheared spheroids into 2D culture led to the formation of dense planar cultures of polarised epithelial cells serving as a suitable in vitro model of H. pylori infection.ConclusionsA robust and quasi-immortal 3D organoid model has been established, which is considered instrumental for future research aimed to understand the underlying mechanisms of infection, mucosal immunity and cancer of the human stomach.

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Immediate tracheal extubation was safe and well tolerated. The incidence of reintubation was not increased when compared to patients in whom extubation succeeded later. However, special attention should be given to transplant recipients presenting in reduced clinical condition at the time of OLT, undergoing complicated surgery, or receiving liver allografts with severe reperfusion injury because of an increased risk for prolonged mechanical ventilation.

The majority of lethal complications after pancreatic head resection are due to septic complications after leakage from the pancreatojejunostomy. Especially the smooth pancreatic remnant is prone to develop parenchymal leaks from shear forces applied during tying of the sutures. We developed a new mattress technique that avoids such shear forces, and we compared this method to the standard Cattell (duct-to-mucosa) technique. A total of 113 patients undergoing standard pancreatic head resection were prospectively randomized to receive either the standard Cattell anastomosis (n = 56) or the new mattress technique (n = 57). All patients were evaluated for surgical and medical complications until discharge. Primary diagnosis and further demographic data compared well between the groups. The time to perform the mattress anastomosis was significantly shorter (15 vs. 22 minutes; p < 0.0001). The incidence of complications at the pancreatojejunostomy, and the length of hospital stay and survival were not significantly different between the two groups; however, a trend toward more reoperations was noted in the Cattell group (10 vs. 5; p < 0.097). The new mattress technique is simple, and our data show that the two techniques yield similar incidences of complications. Therefore the mattress technique for pancreatojejunostomy seems to be safe and is, in our opinion, well suitable for training schedules in pancreatic surgery.