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Find video protocols related to scientific articles indexed in Pubmed.
Challenge or opportunity: outcomes of laparoscopic resection for rectal cancer in patients with high operative risk.
J Laparoendosc Adv Surg Tech A
PUBLISHED: 11-07-2014
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Abstract This study investigated the impact of laparoscopic rectal cancer resection for patients with high operative risk, which was defined as American Society of Anesthesiology (ASA) grades III and IV. This study was conducted at a single center on patients undergoing rectal resection from 2006 to 2010. After screening by ASA grade III or IV, 248 patients who met the inclusion criteria were identified, involving 104 open and 144 laparoscopic rectal resections. The distribution of the Charlson Comorbidity Index was similar between the two groups. Compared with open rectal resection, laparoscopic resection had a significantly lower total complication rate (P<.0001), lower pain rate (P=.0002), and lower blood loss (P<.0001). It is notable that the two groups of patients had no significant difference in cardiac and pulmonary complication rates. Thus, these data showed that the laparoscopic group for rectal cancer could provide short-term outcomes similar to those of their open resection counterparts with high operative risk. The 5-year actuarial survival rates were 0.8361 and 0.8119 in the laparoscopic and open groups for stage I/II (difference not significant), as was the 5-year overall survival rate in stage III/IV (P=.0548). In patients with preoperative cardiovascular or pulmonary disease, the 5-year survival curves were significantly different (P=.0165 and P=.0210), respectively. The cost per patient did not differ between the two procedures. The results of this analysis demonstrate the potential advantages of laparoscopic rectal cancer resection for high-risk patients, although a randomized controlled trial should be conducted to confirm the findings of the present study.
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Modulating CD4+ T Cell Migration in the Postischemic Liver: Hepatic Stellate Cells as New Therapeutic Target?
Transplantation
PUBLISHED: 11-01-2014
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CD4+ T cells play a critical role during hepatic ischemia-reperfusion (I/R) injury although the mechanisms of their migration in the postischemic liver remain unclear. We answered the questions of whether hepatic stellate cells (HSCs) interact with CD4+ T cells during I/R of the liver and whether modulation of HSC activity affects T cell-dependent I/R injury.
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Enhanced expression of BMP6 inhibits hepatic fibrosis in non-alcoholic fatty liver disease.
Gut
PUBLISHED: 07-12-2014
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Bone morphogenetic protein 6 (BMP6) has been identified as crucial regulator of iron homeostasis. However, its further role in liver pathology including non-alcoholic fatty liver disease (NAFLD) and its advanced form non-alcoholic steatohepatitis (NASH) is elusive. The aim of this study was to investigate the expression and function of BMP6 in chronic liver disease.
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Toxicogenomics directory of chemically exposed human hepatocytes.
Arch. Toxicol.
PUBLISHED: 06-04-2014
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A long-term goal of numerous research projects is to identify biomarkers for in vitro systems predicting toxicity in vivo. Often, transcriptomics data are used to identify candidates for further evaluation. However, a systematic directory summarizing key features of chemically influenced genes in human hepatocytes is not yet available. To bridge this gap, we used the Open TG-GATES database with Affymetrix files of cultivated human hepatocytes incubated with chemicals, further sets of gene array data with hepatocytes from human donors generated in this study, and publicly available genome-wide datasets of human liver tissue from patients with non-alcoholic steatohepatitis (NASH), cirrhosis, and hepatocellular cancer (HCC). After a curation procedure, expression data of 143 chemicals were included into a comprehensive biostatistical analysis. The results are summarized in the publicly available toxicotranscriptomics directory ( http://wiki.toxbank.net/toxicogenomics-map/ ) which provides information for all genes whether they are up- or downregulated by chemicals and, if yes, by which compounds. The directory also informs about the following key features of chemically influenced genes: (1) Stereotypical stress response. When chemicals induce strong expression alterations, this usually includes a complex but highly reproducible pattern named 'stereotypical response.' On the other hand, more specific expression responses exist that are induced only by individual compounds or small numbers of compounds. The directory differentiates if the gene is part of the stereotypical stress response or if it represents a more specific reaction. (2) Liver disease-associated genes. Approximately 20 % of the genes influenced by chemicals are up- or downregulated, also in liver disease. Liver disease genes deregulated in cirrhosis, HCC, and NASH that overlap with genes of the aforementioned stereotypical chemical stress response include CYP3A7, normally expressed in fetal liver; the phase II metabolizing enzyme SULT1C2; ALDH8A1, known to generate the ligand of RXR, one of the master regulators of gene expression in the liver; and several genes involved in normal liver functions: CPS1, PCK1, SLC2A2, CYP8B1, CYP4A11, ABCA8, and ADH4. (3) Unstable baseline genes. The process of isolating and the cultivation of hepatocytes was sufficient to induce some stress leading to alterations in the expression of genes, the so-called unstable baseline genes. (4) Biological function. Although more than 2,000 genes are transcriptionally influenced by chemicals, they can be assigned to a relatively small group of biological functions, including energy and lipid metabolism, inflammation and immune response, protein modification, endogenous and xenobiotic metabolism, cytoskeletal organization, stress response, and DNA repair. In conclusion, the introduced toxicotranscriptomics directory offers a basis for a rationale choice of candidate genes for biomarker evaluation studies and represents an easy to use source of background information on chemically influenced genes.
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Specific and nonhepatotoxic degradation of nuclear hepatitis B virus cccDNA.
Science
PUBLISHED: 02-20-2014
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Current antiviral agents can control but not eliminate hepatitis B virus (HBV), because HBV establishes a stable nuclear covalently closed circular DNA (cccDNA). Interferon-? treatment can clear HBV but is limited by systemic side effects. We describe how interferon-? can induce specific degradation of the nuclear viral DNA without hepatotoxicity and propose lymphotoxin-? receptor activation as a therapeutic alternative. Interferon-? and lymphotoxin-? receptor activation up-regulated APOBEC3A and APOBEC3B cytidine deaminases, respectively, in HBV-infected cells, primary hepatocytes, and human liver needle biopsies. HBV core protein mediated the interaction with nuclear cccDNA, resulting in cytidine deamination, apurinic/apyrimidinic site formation, and finally cccDNA degradation that prevented HBV reactivation. Genomic DNA was not affected. Thus, inducing nuclear deaminases-for example, by lymphotoxin-? receptor activation-allows the development of new therapeutics that, in combination with existing antivirals, may cure hepatitis B.
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The organic solute transporters alpha and beta are induced by hypoxia in human hepatocytes.
Liver Int.
PUBLISHED: 01-21-2014
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The organic solute transporters alpha and beta (OST?-OST?) form a heterodimeric transporter located at the basolateral membrane of intestinal epithelial cells and hepatocytes. Liver injury caused by ischaemia-reperfusion, cancer, inflammation or cholestasis can induce a state of hypoxia in hepatocytes. Here, we studied the effect of hypoxia on the expression of OST?-OST?.
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Augmenter of liver regeneration attenuates inflammatory response in the postischemic mouse liver in vivo.
J. Surg. Res.
PUBLISHED: 01-11-2014
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Augmenter of Liver Regeneration (ALR), a protein synthesized in the liver is suggested to be protective against oxidative stress-induced cell death. Hepatic ischemia-reperfusion (I/R) injury is triggered by reactive oxygen species. Here, we tested the hypothesis that ALR attenuates hepatic I/R injury in vivo.
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Liver resection in the elderly: significance of comorbidities and blood loss.
J. Gastrointest. Surg.
PUBLISHED: 01-09-2014
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Liver resection is increasingly performed in elderly patients who are suspected of increased postoperative morbidity (PM) and reduced overall survival (OS). Patient selection based on the identification of age-adjusted risk factors may help to decrease PM and OS.
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Downregulation of P-cadherin expression in hepatocellular carcinoma induces tumorigenicity.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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P-cadherin is a major contributor to cell-cell adhesion in epithelial tissues, playing pivotal roles in important morphogenetic and differentiation processes and in maintaining tissue integrity and homeostasis. Alterations of P-cadherin expression have been observed during the progression of several carcinomas where it appears to act as tumor suppressive or oncogenic in a context-dependent manner. Here, we found a significant downregulation of P-cadherin in hepatocellular carcinoma (HCC) cell lines and tissues compared to primary human hepatocytes and non-malignant liver tissues. Combined immunohistochemical analysis of a tissue microarray containing matched pairs of HCC tissue and corresponding non-tumorous liver tissue of 69 patients confirmed reduced P-cadherin expression in more than half of the cases. In 35 human HCC tissues, the P-cadherin immunosignal was completely lost which correlated with tumor staging and proliferation. Also in vitro, P-cadherin suppression in HCC cells via siRNA induced proliferation compared to cells transfected with control-siRNA. In summary, downregulation of P-cadherin expression appears to induce tumorigenicity in HCC. Therefore, P-cadherin expression may serve as a prognostic marker and therapeutic target of this highly aggressive tumor.
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An Algorithm that Predicts the Viability and the Yield of Human Hepatocytes Isolated from Remnant Liver Pieces Obtained from Liver Resections.
PLoS ONE
PUBLISHED: 01-01-2014
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Isolated human primary hepatocytes are an essential in vitro model for basic and clinical research. For successful application as a model, isolated hepatocytes need to have a good viability and be available in sufficient yield. Therefore, this study aims to identify donor characteristics, intra-operative factors, tissue processing and cell isolation parameters that affect the viability and yield of human hepatocytes. Remnant liver pieces from tissue designated as surgical waste were collected from 1034 donors with informed consent. Human hepatocytes were isolated by a two-step collagenase perfusion technique with modifications and hepatocyte yield and viability were subsequently determined. The accompanying patient data was collected and entered into a database. Univariate analyses found that the viability and the yield of hepatocytes were affected by many of the variables examined. Multivariate analyses were then carried out to confirm the factors that have a significant relationship with the viability and the yield. It was found that the viability of hepatocytes was significantly decreased by the presence of fibrosis, liver fat and with increasing gamma-glutamyltranspeptidase activity and bilirubin content. Yield was significantly decreased by the presence of liver fat, septal fibrosis, with increasing aspartate aminotransferase activity, cold ischemia times and weight of perfused liver. However, yield was significantly increased by chemotherapy treatment. In conclusion, this study determined the variables that have a significant effect on the viability and the yield of isolated human hepatocytes. These variables have been used to generate an algorithm that can calculate projected viability and yield of isolated human hepatocytes. In this way, projected viability can be determined even before isolation of hepatocytes, so that donors that result in high viability and yield can be identified. Further, if the viability and yield of the isolated hepatocytes is lower than expected, this will highlight a methodological problem that can be addressed.
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No activation of human PXR by hyperforin-related phloroglucinols.
J. Pharmacol. Exp. Ther.
PUBLISHED: 11-20-2013
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The acylated phloroglucinol, hyperforin, the main active ingredient of St Johns wort, exerts anti-depressant properties via indirect inhibition of serotonin reuptake by selectively activating the canonical transient receptor potential channel 6 (TRPC6). Hyperforin treatment can lead to drug-drug interactions due to potent activation of the nuclear receptor PXR (NR1I2), a key transcriptional regulator of genes involved in drug metabolism and transport. It was previously shown that synthetic acylated phloroglucinol derivatives activate TRPC6 with similar potency as hyperforin. However, their interaction potential with PXR remained unknown. Here we investigated five synthetic TRPC6 activating phloroglucinol derivatives and four TRPC6 non-activating compounds in comparison to hyperforin and rifampicin for their potential to activate PXR in silico and in vitro. Computational PXR pharmacophore modeling did not indicate potent agonist or antagonist interactions for the TRPC6 activating derivatives while one of them was suggested by docking studies to show both agonist and antagonist interactions. Hyperforin and rifampicin treatment of HepG2 cells co-transfected with human PXR expression-vector and a CYP3A4 promoter-reporter construct resulted in potent PXR-dependent induction, while all TRPC6 activating compounds failed to show any PXR activation or to antagonize rifampicin-mediated CYP3A4 promoter induction. Hyperforin and rifampicin treatment of primary human hepatocytes resulted in highly correlated induction of PXR-target genes, whereas treatment with the phloroglucinol derivatives elicited moderate gene expression changes only weakly correlated to those of rifampicin and hyperforin treatment. These results show that TRPC6-activating phloroglucinols do not activate PXR and should therefore be promising new candidates for further drug development.
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Isolation of human hepatocytes by a two-step collagenase perfusion procedure.
J Vis Exp
PUBLISHED: 09-24-2013
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The liver, an organ with an exceptional regeneration capacity, carries out a wide range of functions, such as detoxification, metabolism and homeostasis. As such, hepatocytes are an important model for a large variety of research questions. In particular, the use of human hepatocytes is especially important in the fields of pharmacokinetics, toxicology, liver regeneration and translational research. Thus, this method presents a modified version of a two-step collagenase perfusion procedure to isolate hepatocytes as described by Seglen (1). Previously, hepatocytes have been isolated by mechanical methods. However, enzymatic methods have been shown to be superior as hepatocytes retain their structural integrity and function after isolation. This method presented here adapts the method designed previously for rat livers to human liver pieces and results in a large yield of hepatocytes with a viability of 77±10%. The main difference in this procedure is the process of cannulization of the blood vessels. Further, the method described here can also be applied to livers from other species with comparable liver or blood vessel sizes.
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RNA stability in human liver: comparison of different processing times, temperatures and methods.
Mol. Biotechnol.
PUBLISHED: 05-28-2013
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The accuracy of information garnered by real-time quantitative polymerase chain reaction (RT-qPCR), an important technology for elucidating molecular mechanisms of disease, is dependent on tissue quality. Thus, this study aimed to determine the effects of intra-operative manipulation, extended processing times, different temperatures or storage in RNAlater on RNA quality in liver samples for tissue banking. Liver samples, flash-frozen or in RNAlater, were collected over a time course (during surgery before blood arrest up to 1 day after surgery) with samples kept either at room temperature (RT) or on ice. This study showed that at the longest time-point at RT, the RNA quality decreased significantly by 20%. However, relative gene expressions of FOS, GUSB, MYC, HIF1? and GFER were in general not significantly different when the time-points were compared. In conclusion, samples should be kept on ice during processing, and either RNAlater or snap-freezing should be utilised for storage. Further, intra-operative manipulation and extended postoperative processing time generally does not change relative gene expression levels for the 5 genes studied, making such sampling suitable for RT-qPCR analysis. Thus, if relative gene expression of a gene of interest is stable, these guidelines will lead to increased accrual of samples to the tissue bank.
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Recent advances in 2D and 3D in vitro systems using primary hepatocytes, alternative hepatocyte sources and non-parenchymal liver cells and their use in investigating mechanisms of hepatotoxicity, cell signaling and ADME.
Patricio Godoy, Nicola J Hewitt, Ute Albrecht, Melvin E Andersen, Nariman Ansari, Sudin Bhattacharya, Johannes Georg Bode, Jennifer Bolleyn, Christoph Borner, Jan Böttger, Albert Braeuning, Robert A Budinsky, Britta Burkhardt, Neil R Cameron, Giovanni Camussi, Chong-Su Cho, Yun-Jaie Choi, J Craig Rowlands, Uta Dahmen, Georg Damm, Olaf Dirsch, María Teresa Donato, Jian Dong, Steven Dooley, Dirk Drasdo, Rowena Eakins, Karine Sá Ferreira, Valentina Fonsato, Joanna Fraczek, Rolf Gebhardt, Andrew Gibson, Matthias Glanemann, Chris E P Goldring, Maria José Gómez-Lechón, Geny M M Groothuis, Lena Gustavsson, Christelle Guyot, David Hallifax, Seddik Hammad, Adam Hayward, Dieter Häussinger, Claus Hellerbrand, Philip Hewitt, Stefan Hoehme, Hermann-Georg Holzhütter, J Brian Houston, Jens Hrach, Kiyomi Ito, Hartmut Jaeschke, Verena Keitel, Jens M Kelm, B Kevin Park, Claus Kordes, Gerd A Kullak-Ublick, Edward L Lecluyse, Peng Lu, Jennifer Luebke-Wheeler, Anna Lutz, Daniel J Maltman, Madlen Matz-Soja, Patrick McMullen, Irmgard Merfort, Simon Messner, Christoph Meyer, Jessica Mwinyi, Dean J Naisbitt, Andreas K Nüssler, Peter Olinga, Francesco Pampaloni, Jingbo Pi, Linda Pluta, Stefan A Przyborski, Anup Ramachandran, Vera Rogiers, Cliff Rowe, Celine Schelcher, Kathrin Schmich, Michael Schwarz, Bijay Singh, Ernst H K Stelzer, Bruno Stieger, Regina Stöber, Yuichi Sugiyama, Ciro Tetta, Wolfgang E Thasler, Tamara Vanhaecke, Mathieu Vinken, Thomas S Weiss, Agata Widera, Courtney G Woods, Jinghai James Xu, Kathy M Yarborough, Jan G Hengstler.
Arch. Toxicol.
PUBLISHED: 05-02-2013
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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-4?, 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-4?), 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.
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Management of acute upside-down stomach.
BMC Surg
PUBLISHED: 03-14-2013
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Upside-down stomach (UDS) is characterized by herniation of the entire stomach or most gastric portions into the posterior mediastinum. Symptoms may vary heavily as they are related to reflux and mechanically impaired gastric emptying. UDS is associated with a risk of incarceration and volvulus development which both might be complicated by acute gastric outlet obstruction, advanced ischemia, gastric bleeding and perforation.
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Clinical outcome of IBD-associated versus sporadic colorectal cancer: a matched-pair analysis.
J. Gastrointest. Surg.
PUBLISHED: 02-08-2013
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This study assesses the perioperative course and long-term survival of inflammatory bowel disease (IBD)-associated vs. sporadic colorectal cancer (IBD-CRC vs. SCRC) after elimination of known confounders.
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High throughput transcriptome analysis of lipid metabolism in Syrian hamster liver in absence of an annotated genome.
BMC Genomics
PUBLISHED: 01-10-2013
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Whole transcriptome analyses are an essential tool for understanding disease mechanisms. Approaches based on next-generation sequencing provide fast and affordable data but rely on the availability of annotated genomes. However, there are many areas in biomedical research that require non-standard animal models for which genome information is not available. This includes the Syrian hamster Mesocricetus auratus as an important model for dyslipidaemia because it mirrors many aspects of human disease and pharmacological responses. We show that complementary use of two independent next generation sequencing technologies combined with mapping to multiple genome databases allows unambiguous transcript annotation and quantitative transcript imaging. We refer to this approach as "triple match sequencing" (TMS).
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Expression and function of methylthioadenosine phosphorylase in chronic liver disease.
PLoS ONE
PUBLISHED: 01-01-2013
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To study expression and function of methylthioadenosine phosphorylase (MTAP), the rate-limiting enzyme in the methionine and adenine salvage pathway, in chronic liver disease.
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Effect of GLP1R agonists taspoglutide and liraglutide on primary thyroid C-cells from rodent and man.
J. Mol. Endocrinol.
PUBLISHED: 01-01-2013
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Glucagon-like peptide 1 (GLP1) analogs have been associated with an increased incidence of thyroid C-cell hyperplasia and tumors in rodents. This effect may be due to a GLP1 receptor (GLP1R)-dependent mechanism. As the expression of GLP1R is much lower in primates than in rodents, the described C-cell proliferative lesions may not be relevant to man. Here, we aimed to establish primary thyroid cell cultures of rat and human to evaluate the expression and function of GLP1R in C-cells. In our experiments, GLP1R expression was observed in primary rat C-cells (in situ hybridization) but was not detected in primary human C-cells (mRNA and protein levels). The functional response of the cultures to the stimulation with GLP1R agonists is an indirect measure of the presence of functional receptor. Liraglutide and taspoglutide elicited a modest increase in calcitonin release and in calcitonin expression in rat primary thyroid cultures. Contrarily, no functional response to GLP1R agonists was observed in human thyroid cultures, despite the presence of few calcitonin-positive C-cells. Thus, the lack of functional response of the human cultures adds to the weight of evidence indicating that healthy human C-cells have very low levels or completely lack GLP1R. In summary, our results support the hypothesis that the GLP1R agonist-induced C-cell responses in rodents may not be relevant to primates. In addition, the established cell culture method represents a useful tool to study the physiological and/or pathological roles of GLP1 and GLP1R agonists on normal, non-transformed primary C-cells from rats and man.
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Hop bitter acids exhibit anti-fibrogenic effects on hepatic stellate cells in vitro.
Exp. Mol. Pathol.
PUBLISHED: 09-05-2011
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Female inflorescences of the hop plant Humulus lupulus L. contain a variety of secondary metabolites with bitter acids (BA) as quantitatively dominating secondary metabolites. The use of hops in beer brewing has a long history due to the antibacterial effects of the BA and their typical bitter taste. Furthermore, hop cones are used in traditional medicine and for pharmaceutical purposes. Recent studies indicate that BA may affect activity of the transcription factor NF?B. NF?B plays a key role in the activation process of hepatic stellate cells (HSC), which is the key event of hepatic fibrosis. The aim of this study was to investigate the effect of BA on HSC (activation) and their potential to inhibit molecular processes involved in the pathogenesis of hepatic fibrosis. HSC were isolated from murine and human liver tissue and incubated with a characterized fraction of bitter acids purified from a CO(2) hop extract. At a concentration of 25?g/ml BA started to induce LDH leakage. Already at lower concentrations BA lead to a dose dependent inhibition of HSC proliferation and inhibited I?B-?-phosphorylation, nuclear p65 translocation and binding activity in a dose dependent way (up to 10?g/ml). Accordingly, the same BA-doses inhibited the expression of pro-inflammatory and NF?B regulated genes as MCP-1 and RANTES, but did not affect expression of genes not related to NF?B signaling. In addition to the effect on activated HSC, BA inhibited the in vitro activation process of freshly isolated HSC as evidenced by delayed expression of collagen I and ?-SMA mRNA and protein. Together, these findings indicate that BA inhibit NF?B activation, and herewith the activation and development of profibrogenic phenotype of HSC. Thus, bitter acids appear as potential functional nutrients for the prevention or treatment hepatic fibrosis in chronic liver disease.
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Inferring statin-induced gene regulatory relationships in primary human hepatocytes.
Bioinformatics
PUBLISHED: 07-14-2011
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Statins are the most widely used cholesterol-lowering drugs. The primary target of statins is HMG-CoA reductase, a key enzyme in cholesterol synthesis. However, statins elicit pleitropic responses including beneficial as well as adverse effects in the liver or other organs. Today, the regulatory mechanisms that cause these pleiotropic effects are not sufficiently understood.
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Pulmonary sclerosing hemangioma in a 21-year-old male with metastatic hereditary non-polyposis colorectal cancer: report of a case.
World J Surg Oncol
PUBLISHED: 06-06-2011
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Pulmonary sclerosing hemangioma (SH) is a rare tumor of the lung predominantly affecting Asian women in their fifth decade of life. SH is thought to evolve from primitive respiratory epithelium and mostly shows benign biological behavior; however, cases of lymph node metastases, local recurrence and multiple lesions have been described.
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A systems biology approach to dynamic modeling and inter-subject variability of statin pharmacokinetics in human hepatocytes.
BMC Syst Biol
PUBLISHED: 05-06-2011
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The individual character of pharmacokinetics is of great importance in the risk assessment of new drug leads in pharmacological research. Amongst others, it is severely influenced by the properties and inter-individual variability of the enzymes and transporters of the drug detoxification system of the liver. Predicting individual drug biotransformation capacity requires quantitative and detailed models.
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Novel surgical technique for complete traumatic rupture of the pancreas: A case report.
J Med Case Rep
PUBLISHED: 04-25-2011
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Complete pancreatic rupture is a rare injury. The typical mechanism by which this occurs is overstretching of the pancreas across the vertebral column during blunt abdominal trauma. The management of this injury depends on the location and extent of the injury.
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Cell therapeutic options in liver diseases: cell types, medical devices and regulatory issues.
J Mater Sci Mater Med
PUBLISHED: 03-15-2011
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Although significant progress has been made in the field of orthotopic liver transplantation, cell-based therapies seem to be a promising alternative to whole-organ transplantation. The reasons are manifold but organ shortage is the main cause for this approach. However, many problems such as the question which cell type should be used or which application site is best for transplantation have been raised. In addition, some clinicians have had success by cultivating liver cells in bioreactors for temporary life support. Besides answering the question which cell type, which injection site or even which culture form should be used for liver support recent international harmonization of legal requirements is needed to be addressed by clinicians, scientists and companies dealing with cellular therapies. We here briefly summarize the possible cell types used to partially or temporarily correct liver diseases, the most recent development of bioreactor technology and important regulatory issues.
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Augmenter of liver regeneration (ALR) protects human hepatocytes against apoptosis.
Biochem. Biophys. Res. Commun.
PUBLISHED: 11-10-2010
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Augmenter of liver regeneration (ALR) is known to support liver regeneration and to stimulate proliferation of hepatocytes. However, it is not known if ALR exerts anti-apoptotic effects in human hepatocytes and whether this protective effect is cell type specific. This is relevant, because compounds that protect the liver against apoptosis without undesired effects, such as protection of metastatic tumour cells, would be appreciated in several clinical settings. Primary human hepatocytes (phH) and organotypic cancer cell lines were exposed to different concentrations of apoptosis inducers (ethanol, TRAIL, anti-Apo, TGF-?, actinomycin D) and cultured with or without recombinant human ALR (rhALR). Apoptosis was evaluated by the release of cytochrome c from mitochondria and by FACS with propidium iodide (PI) staining. ALR significantly decreased apoptosis induced by ethanol, TRAIL, anti-Apo, TGF-? and actinomycin D. Further, the anti-apoptotic effect of ALR was observed in primary human hepatocytes and in HepG2 cells but not in bronchial (BC1), colonic (SW480), gastric (GC1) and pancreatic (L3.6PL) cell lines. Therefore, the hepatotrophic growth factor ALR acts in a liver specific manner with regards to both its mitogenic and its anti-apoptotic effect. Unlike the growth factors HGF and EGF, rhALR acts in a liver specific manner. Therefore, ALR is a promising candidate for further evaluation as a possible hepatoprotective factor in clinical settings.
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Profiling induction of cytochrome p450 enzyme activity by statins using a new liquid chromatography-tandem mass spectrometry cocktail assay in human hepatocytes.
Drug Metab. Dispos.
PUBLISHED: 06-15-2010
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Human hepatocytes in primary culture are a very useful model to directly assess induction of gene expression by xenobiotics. We developed a cytochrome P450 (P450) activity cocktail assay using model substrates for the seven important P450s 1A2 (phenacetin), 2B6 (bupropion), 2C8 (amodiaquine), 2C9 (tolbutamide), 2C19 (S-mephenytoin), 2D6 (propafenone), and 3A4 (atorvastatin). Metabolite formation was determined by liquid chromatography-tandem mass spectrometry in hepatocyte culture supernatants. Atorvastatin has not been previously assessed as a CYP3A probe drug. We demonstrate highly selective atorvastatin ortho-hydroxylation by CYP3A4 by recombinant P450s. In human liver microsomes ortho-hydroxyatorvastatin formation was highly correlated with CYP3A4 protein content (r(s) = 0.78, p < 0.0001, n = 150). We profiled induction of these P450 activities in primary human hepatocytes after treatment with 30 microM atorvastatin, lovastatin, pravastatin, rosuvastatin, and simvastatin for 24 to 72 h. Except for pravastatin, all statins induced P450 activities to various degrees, approximately in the order atorvastatin > simvastatin > lovastatin > rosuvastatin. Inducibility of P450s followed the order CYP2C8 > CYP3A4 > CYP2C9 > CYP2B6 > CYP2C19 approximately CYP2D6 > CYP1A2. The strongest induction was observed for amodiaquine N-desalkylation, which was induced approximately 20-fold. Quantitative reverse transcription-polymerase chain reaction confirmed corresponding changes on the mRNA level with even more dramatic induction up to almost 100-fold. These data suggest a broader inducing effect of statins on cytochrome P450s and possibly other absorption, distribution, metabolism, and excretion genes than previously known, thus further emphasizing their drug-drug interaction potential. Our cocktail assay should be helpful for economical use of human hepatocytes in the assessment of P450 induction by drugs and drug candidates.
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Genetic inactivation of the Fanconi anemia gene FANCC identified in the hepatocellular carcinoma cell line HuH-7 confers sensitivity towards DNA-interstrand crosslinking agents.
Mol. Cancer
PUBLISHED: 05-28-2010
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Inactivation of the Fanconi anemia (FA) pathway through defects in one of 13 FA genes occurs at low frequency in various solid cancer entities among the general population. As FA pathway inactivation confers a distinct hypersensitivity towards DNA interstrand-crosslinking (ICL)-agents, FA defects represent rational targets for individualized therapeutic strategies. Except for pancreatic cancer, however, the prevalence of FA defects in gastrointestinal (GI) tumors has not yet been systematically explored.
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Cell cycle progression or translation control is not essential for vesicular stomatitis virus oncolysis of hepatocellular carcinoma.
PLoS ONE
PUBLISHED: 05-10-2010
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The intrinsic oncolytic specificity of vesicular stomatitis virus (VSV) is currently being exploited to develop alternative therapeutic strategies for hepatocellular carcinoma (HCC). Identifying key regulators in diverse transduction pathways that define VSV oncolysis in cancer cells represents a fundamental prerequisite to engineering more effective oncolytic viral vectors and adjusting combination therapies. After having identified defects in the signalling cascade of type I interferon induction, responsible for attenuated antiviral responses in human HCC cell lines, we have now investigated the role of cell proliferation and translation initiation. Cell cycle progression and translation initiation factors eIF4E and eIF2Bepsilon have been recently identified as key regulators of VSV permissiveness in T-lymphocytes and immortalized mouse embryonic fibroblasts, respectively. Here, we show that in HCC, decrease of cell proliferation by cell cycle inhibitors or siRNA-mediated reduction of G(1) cyclin-dependent kinase activities (CDK4) or cyclin D1 protein expression, do not significantly alter viral growth. Additionally, we demonstrate that translation initiation factors eIF4E and eIF2Bepsilon are negligible in sustaining VSV replication in HCC. Taken together, these results indicate that cellular proliferation and the initiation phase of cellular protein synthesis are not essential for successful VSV oncolysis of HCC. Moreover, our observations indicate the importance of cell-type specificity for VSV oncolysis, an important aspect to be considered in virotherapy applications in the future.
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Augmenter of liver regeneration causes different kinetics of ERK1/2 and Akt/PKB phosphorylation than EGF and induces hepatocyte proliferation in an EGF receptor independent and liver specific manner.
Biochem. Biophys. Res. Commun.
PUBLISHED: 03-09-2010
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Augmenter of liver regeneration (ALR) is a potent growth factor which supports liver regeneration in experimental animals. The aim of this study was to compare proliferation as well as the kinetics of ERK1/2 and Akt/PKB phosphorylation by recombinant human ALR (rhALR) and EGF in human hepatocytes and extrahepatic cells.
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Description and evaluation of a bench porcine model for teaching surgical residents vascular anastomosis skills.
BMC Res Notes
PUBLISHED: 02-16-2010
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Numerous models, of variable quality, exist to impart the complex skills required to perform vascular anastomosis. These models differ with regard to the kinds of materials used, as well as their sizes, the time needed for their preparation, their availability, and the associated costs. The present study describes a bench model that uses formalin-fixed porcine aorta, and its evaluation by young surgical residents during a recent skills course.
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Neohepatocytes from alcoholics and controls express hepatocyte markers and display reduced fibrogenic TGF-ß/Smad3 signaling: advantage for cell transplantation?
Alcohol. Clin. Exp. Res.
PUBLISHED: 01-26-2010
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Liver transplantation is the only definitive treatment for end stage liver disease. Donor organ scarcity raises a growing interest in new therapeutic options. Recently, we have shown that injection of monocyte-derived NeoHepatocytes can increase survival in rats with extended liver resection. In order to apply this technology in humans with chronic liver diseases in an autologous setting, we generated NeoHepatocytes from patients with alcoholic liver disease and healthy controls and compared those to human hepatocytes.
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Determinants of morbidity and survival after elective non-curative resection of stage IV colon and rectal cancer.
Int J Colorectal Dis
PUBLISHED: 05-13-2009
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The benefit of elective primary tumor resection for non-curable stage IV colorectal cancer (CRC) remains largely undefined. We wanted to identify risk factors for postoperative complications and short survival.
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Mst1 and Mst2 maintain hepatocyte quiescence and suppress hepatocellular carcinoma development through inactivation of the Yap1 oncogene.
Cancer Cell
PUBLISHED: 05-06-2009
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Hippo-Lats-Yorkie signaling regulates tissue overgrowth and tumorigenesis in Drosophila. We show that the Mst1 and Mst2 protein kinases, the mammalian Hippo orthologs, are cleaved and constitutively activated in the mouse liver. Combined Mst1/2 deficiency in the liver results in loss of inhibitory Ser127 phosphorylation of the Yorkie ortholog, Yap1, massive overgrowth, and hepatocellular carcinoma (HCC). Reexpression of Mst1 in HCC-derived cell lines promotes Yap1 Ser127 phosphorylation and inactivation and abrogates their tumorigenicity. Notably, Mst1/2 inactivates Yap1 in liver through an intermediary kinase distinct from Lats1/2. Approximately 30% of human HCCs show low Yap1(Ser127) phosphorylation and a majority exhibit loss of cleaved, activated Mst1. Mst1/2 inhibition of Yap1 is an important pathway for tumor suppression in liver relevant to human HCC.
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Rectal prolapse.
J. Gastrointest. Surg.
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A 56-year-old male presented to the emergency department with a feeling of heaviness and a protruding mass at the anal verge associated with pruritus in this area. The patient did not feel any pain and did not report experiencing faecal incontinence. Physical examination resulted in the visual diagnosis of a total rectal prolapse. Immediate manual repositioning through gentle pressure succeeded and the patient was scheduled for an elective laparoscopic ventral rectopexy.
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Expression and function of the atypical cadherin FAT1 in chronic liver disease.
Biochem. Biophys. Res. Commun.
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Hepatic fibrosis can be considered as wound healing process in response to hepatocellular injury. Activation of hepatic stellate cells (HSCs) is a key event of hepatic fibrosis since activated HSCs are the cellular source of enhanced extracellular matrix deposition, and reversion of liver fibrosis is accompanied by clearance of activated HSCs by apoptosis. The atypical cadherin FAT1 has been shown to regulate diverse biological functions as cell proliferation and planar cell polarity, and also to affect wound healing. Here, we found increased FAT1 expression in different murine models of chronic liver injury and in cirrhotic livers of patients with different liver disease. Also in hepatic tissue of patients with non-alcoholic steatohepatitis FAT1 expression was significantly enhanced and correlated with collagen alpha I(1) expression. Immunohistochemistry revealed no significant differences in staining intensity between hepatocytes in normal and cirrhotic liver tissue but myofibroblast like cells in fibrotic septa of cirrhotic livers showed a prominent immunosignal. Furthermore, FAT1 mRNA and protein expression markedly increased during in vitro activation of primary human and murine HSCs. Together, these data indicated activated HSCs as cellular source of enhanced FAT1 expression in diseased livers. To gain insight into the functional role of FAT1 in activated HSCs we suppressed FAT1 in these cells by siRNA. We newly found that FAT1 suppression in activated HSCs caused a downregulation of NF?B activity. This transcription factor is critical for apoptosis resistance of HSCs, and consequently, we detected a higher apoptosis rate in FAT1 suppressed HSCs compared to control cells. Our findings suggest FAT1 as new therapeutic target for the prevention and treatment of hepatic fibrosis in chronic liver disease.
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Hartmanns procedure or primary anastomosis?
Dig Dis
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Perforation following acute diverticulitis is a typical scenario during the first attack. Different classification systems exist to classify acute perforated diverticulitis. While the Hinchey classification, which is based on intraoperative findings, is internationally best known, the German Hansen-Stock classification which is based on CT scan is widely accepted within Germany. When surgery is necessary, sigmoid colectomy is the standard of care. An important question is whether patients should receive primary anastomosis or a Hartmann procedure subsequently. A priori there are several arguments for both procedures. Hartmanns operation is extremely safe and, therefore, represents the best option in severely ill patients and/or extensive peritonitis. However, this operation carries a high risk of stoma nonreversal, or, when reversal is attempted, a high risk in terms of morbidity and mortality. In contrast, primary anastomosis with or without loop ileostoma is a slightly more lengthy procedure as normally the splenic flexure needs to be mobilized and construction of the anastomosis may consume more time than the Hartmann operation. The big advantage of primary anastomosis, however, is that there is no need for the potentially risky stoma reversal operation. The most interesting question is when to do the Hartmann operation or primary anastomosis. Several comparative case series were published showing that primary anastomosis is feasible in many patients. However, no randomized trial is available to date. It is of note, that all non-randomized case series are biased, i.e. that patients in better condition received anastomosis and those with severe peritonitis underwent Hartmanns operation. This bias is undoubtedly likely to be present, even if not obvious, in the published papers! Our own data suggest that this decision should not be based on the extent of peritonitis but rather on patient condition and comorbidity. In conclusion, sigmoid colectomy and primary anastomosis is feasible and safe in many patients who need surgery for perforated diverticulitis, particularly when combined with loop ileostomy. Based on our own published analysis, however, we recommend performing Hartmanns operation in severely ill patients who carry substantial comorbidity, while the extent of peritonitis appears not to be of predominant importance.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.