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Dive into the research topics where Christoph Jochum is active.

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Featured researches published by Christoph Jochum.


Hepatology | 2010

Acute liver failure is associated with elevated liver stiffness and hepatic stellate cell activation

Alexander Dechêne; Jan-Peter Sowa; Robert K. Gieseler; Christoph Jochum; Lars P. Bechmann; Amr El Fouly; Martin Schlattjan; Fuat H. Saner; Hideo Baba; Andreas Paul; Volker Dries; M. Odenthal; Guido Gerken; Scott L. Friedman; Ali Canbay

Acute liver failure (ALF) is associated with massive short‐term cell death, whereas chronic liver injury is accompanied by continuous cell death. Hepatic stellate cells (HSCs) contribute to tissue repair and liver fibrosis in chronic liver injury, although their role in ALF remains unexplained. Twenty‐nine patients (median age = 43 years, 17 females and 12 males) with ALF according to the Acute Liver Failure Study Group criteria were included. Upon the diagnosis of ALF and after 7 days, we determined liver stiffness (LS) with FibroScan, standard laboratory parameters, and serum levels of matrix metalloproteinase 1 (MMP‐1), MMP‐2, MMP‐9, tissue inhibitor of metalloproteinases 1 (TIMP‐1), TIMP‐2, hyaluronic acid, and markers of overall cell death (M65) and apoptosis (M30). Stellate cell activation and progenitor response were analyzed immunohistochemically in biopsy samples of 12 patients with α‐smooth muscle actin (α‐SMA), keratin‐17, and keratin‐19 staining, respectively. Cell death markers (M30 level = 2243 ± 559.6 U/L, M65 level = 3732 ± 839.9 U/L) and fibrosis markers (TIMP‐1 level = 629.9 ± 69.4 U/mL, MMP‐2 level = 264 ± 32.5 U/mL, hyaluronic acid level = 438.5 ± 69.3 μg/mL) were significantly increased in patients versus healthy controls. This was paralleled by collagen deposition, elevated α‐SMA expression, and higher LS (25.6 ± 3.0 kPa). ALF was associated with ductular progenitor proliferation. Conclusion: Our results demonstrate HSC activation and a progenitor response in ALF. Positive correlations between LS, the degree of liver cell damage, and the intensity of HSC activation suggest that fibrosis is a response to ALF in an attempt to repair damaged tissue. (Hepatology 2010)


Liver Transplantation | 2004

Volumetric and functional recovery of the liver after right hepatectomy for living donation

Silvio Nadalin; Giuliano Testa; Massimo Malago; Mechtild Beste; Andrea Frilling; Thobias Schroeder; Christoph Jochum; Guido Gerken; Christoph E. Broelsch

Our objective was to study the kinetics of recovery of the liver volume and liver function after right hepatectomy (RH) for living donation, comparing conventional and quantitative liver function tests, i.e., galactose elimination capacity (GEC). A total of 27 donors underwent RH averaging 61% of the whole liver volume. The conventional and quantitative liver function tests, as well as magnetic resonance imaging volumetric studies, were performed preoperatively at postoperative day (POD) 10, 90, 180, and 360. Mean residual volume increased by 88% within 10 days from RH and thereafter did not show any significant variation. After 1 year, only 83% of the original volume was reached. GEC per milliliter of liver volume expressed in percent of initial value (GEC/mL) showed a decrease of 25% at POD10, an increase up to 125% at POD 180, and returned to normal values at POD 360. Liver biochemistries, International Normalized Ratio (INR), and bilirubin returned to normal in 10 days. Cholinesterase showed a similar course like GEC. In conclusion, within 10 days of 61% loss of its initial volume, the liver is capable of regenerating a volume necessary to its function, although it corresponds to only 74% of the initial one. It takes only 10 days to normalize liver biochemistries, while cholinesterase and albumin recover over 90 days. However, a direct measure of the cytosolic liver function obtained by GEC shows that functional recovery occurs much more gradually than the recovery of volume and liver biochemistries. (Liver Transpl 2004;10:1024–1029.)


Liver International | 2009

Apoptosis is associated with CD36/fatty acid translocase upregulation in non-alcoholic steatohepatitis

Lars P. Bechmann; Jan-Peter Sowa; Alisan Kahraman; Jochen Erhard; Inga Wedemeyer; Barbara Emons; Christoph Jochum; Thorsten Feldkamp; Guido Gerken; Ali Canbay

Background & aims: Hepatocyte apoptosis is a key event in non‐alcoholic steatohepatitis (NASH). We studied the effect of obesity on free fatty acid (FFA) levels, fatty acid transport proteins (FATPs) and on extrinsic and intrinsic activation of apoptosis in the liver.


Gut | 2015

Vitamin D counteracts fibrogenic TGF-β signalling in human hepatic stellate cells both receptor-dependently and independently

Anja Beilfuss; Jan-Peter Sowa; Svenja Sydor; Mechthild Beste; Lars P. Bechmann; Martin Schlattjan; Wing-Kin Syn; Inga Wedemeyer; Zoltan Mathe; Christoph Jochum; Guido Gerken; Robert K. Gieseler; Ali Canbay

Objective Non-alcoholic fatty liver disease (NAFLD) is closely linked to obesity and constitutes part of the metabolic syndrome, which have been associated with low serum vitamin D (VD). Due to known crosstalk between VD and transforming growth factor (TGF)-β signalling, VD has been proposed as an antifibrotic treatment. Design We evaluated the association between VD, the vitamin D receptor (VDR) and liver fibrosis in primary human hepatic stellate cells (phHSC) and 106 morbidly obese patients with NAFLD. Results Treating phHSC with VD ameliorated TGF-β-induced fibrogenesis via both VDR-dependent and VDR-independent mechanisms. Reduction of fibrogenic response was abolished in cells homozygous for GG at the A1012G single nucleotide polymorphisms within the VDR gene. Compared with healthy livers, NAFLD livers expressed higher levels of VDR mRNA and VDR fragments. VDR mRNA was lower in patients homozygous for GG at A1012G and expression of pro-fibrogenic genes was higher in patients carrying the G allele. Conclusions VD may be an antifibrotic treatment option early in the onset of fibrosis in specific genotypes for VDR. Known polymorphisms of the VDR may influence the response to VD treatment.


Journal of Hepatology | 2009

Adiponectin inhibits steatotic CD95/Fas up-regulation by hepatocytes: therapeutic implications for hepatitis C.

Inga Wedemeyer; Lars P. Bechmann; M. Odenthal; Christoph Jochum; Guido Marquitan; Uta Drebber; Guido Gerken; Hans Peter Dienes; Ali Canbay

BACKGROUND/AIMS Steatosis may trigger hepatocytes to up-regulate CD95/Fas thereby increasing susceptibility to apoptosis, inflammation and fibrosis. We investigated this concept and potential roles of adiponectin and its receptors (AdipoR1; AdipoR2) in chronically HCV-infected patients. METHODS In 98 HCV+ patients and 20 controls, sera were tested for HCV genotypes, FFAs, adiponectin and the M30 apoptosis indicator, and biopsies were evaluated for steatosis/inflammation/fibrosis, CD95/Fas (mRNA/protein), adiponectin (mRNA/protein), AdipoR1/-R2 (mRNA) and M30 (protein). We also questioned whether adiponectin protects HepG2 hepatoblastoma cells from FFA-triggered CD95/Fas up-regulation and apoptosis. RESULTS Patients [HCV clades 1 (78%), 2 (3%) and 3 (19%)] revealed increased FFA and adiponectin serum levels (p = .005). Hepatocyte CD95/Fas up-regulation correlated with steatosis, inflammation and fibrosis (p = .004). Advanced fibrosis correlated significantly (p = .05) with serum M30. Liver adiponectin correlated with steatosis (p = .016), CD95/Fas (p < .001) and inflammation/fibrosis. Hepatocyte AdipoR2 mRNA specifically correlated with serum adiponectin and steatosis (p = .003), while hepatocyte AdipoR1 mRNA dropped in pronounced fibrosis (p = .060). Finally, adiponectin protected HepG2 cells from FFA-triggered CD95/Fas expression and induction of apoptosis (p = .0396). CONCLUSIONS In chronic HCV infection, steatosis up-regulates hepatocyte CD95/Fas and thus increases apoptosis, which facilitates inflammation and fibrosis. The physiologic countermeasure of adiponectin up-regulation may offer clues for future therapeutic intervention.


Zeitschrift Fur Gastroenterologie | 2009

Acute Liver Failure in a Metropolitan Area in Germany: a Retrospective Study (2002 – 2008)

Ali Canbay; Christoph Jochum; Lars P. Bechmann; S. Festag; Robert K. Gieseler; Z. Yüksel; Lütkes P; Fuat H. Saner; Andreas Paul; Guido Gerken

OBJECTIVES To determine current etiologies of acute liver failure (ALF) and clinical and laboratory parameters associated with the outcome upon ALF, so as to identify the frequency of present causes of ALF in Germany as well as potential new prognostic parameters. PATIENTS 134 adult patients (63 % females / 37 % males) aged 41 +/- 16 years (median: 38 years) with established ALF criteria. DESIGN AND SETTING A retrospective study (1 / 2002 - 4 / 2008) on ALF patients from the Ruhr Area, the largest urban region located in northwestern Germany. Clinical and laboratory data were collected for a period of four weeks after study admission. RESULTS Etiologies of ALF were identified as drug toxicity (39.6 % of the cases); combined viral hepatitides (23.1 %); or miscellaneous (16.4 %). In 20.9 % of the cases, the etiology remained indeterminate. Overall patient survival at four weeks was 81.3 %. While 89 patients (66.4 %) recovered under best supportive therapy, 26 patients (19.4 %) had to undergo liver transplantation. Increased body mass indices were significantly (p < 0.003) associated with a poor outcome. Intriguingly, high levels of cholestatic enzymes significantly (p < 0.01) correlated with a positive outcome. CONCLUSIONS In providing first data on current ALF etiologies Germany, this study reveals that drug toxicity - in particular due to acetaminophen - has replaced viral hepatitis as the most single frequent cause of ALF in a densely populated urban area; this correlates with similar findings in the USA, the UK and Scandinavia. Lower body mass indices and elevated cholestatic enzyme levels had statistically significant prognostic power.


Digestion | 2009

Hepatitis B-Associated Acute Liver Failure: Immediate Treatment with Entecavir Inhibits Hepatitis B Virus Replication and Potentially Its Sequelae

Christoph Jochum; Isabella Gawlista; A. Fiedler; Paul Manka; Fuat H. Saner; Michael Roggendorf; Guido Gerken; Ali Canbay

Background: Acute hepatitis B virus (HBV) infection is followed by high viral replication rates leading to hepatocyte death and ultimately, in some cases, to acute liver failure (ALF) necessitating liver transplantation. Thus, the objective of treating HBV-induced ALF is to eliminate or significantly suppress HBV replication. Methods/Results: This prospective study (02/2008–02/2009) included 6 patients (1 female and 5 males, median age 35.5 years). HBV DNA and hepatitis B surface antigen (HBsAg) levels were detected, and hepatocyte death was quantified in patients’ sera by (a) M65 ELISA and (b) M30 ELISA. All patients received entecavir treatment at 1 mg daily within 1–18 days after admission. Upon treatment, pathologic parameters rapidly decreased and returned to normal values or trace amounts (HBV DNA) within 3 months in all of the cases. A seroconversion to anti-HBsAg was achieved in 5 out of 6 patients; one patient with late onset of treatment did not seroconvert. M65 and the difference of M65-M30 as a marker for cell necrosis dropped significantly within 1 week of treatment. Conclusion: This preliminary series of 6 patients reveals that immediate treatment of HBV-induced ALF with entecavir is well tolerated and beneficially affects the course of the disease.


Digestion | 2012

Acute Management of Refractory Variceal Bleeding in Liver Cirrhosis by Self-Expanding Metal Stents

Alexander Dechêne; A.H. El Fouly; Lars P. Bechmann; Christoph Jochum; Fuat H. Saner; Guido Gerken; Ali Canbay

Background and Aims: Current treatment strategies of variceal bleeding (VB) include banding and sclerotherapy. However, up to 10% of bleeding events remain refractory to standard therapy with high mortality. With this study, we aimed to evaluate the implantation of self-expanding metal stents (SEMS) for the management of therapy-refractory variceal bleeding. Patients and Methods: Eight cirrhotic patients who presented to our unit with a total of 9 refractory bleeding events were treated by SEMS placement. Results: Stenting resulted in immediate hemostasis in all cases without recurrent bleeding with SEMS in situ. After stabilization, 1 patient was treated by transjugular intrahepatic portosystemic shunt (TIPS) and after the second bleeding episode by TIPS dilation. One patient underwent orthotopic liver transplantation (OLT). The remaining patients were treated with standard drug regimens to reduce portal pressure. The SEMS were removed after a median of 11 days. No acute hemorrhage was noted on stent retrieval. While no early rebleeding occurred in the patients after TIPS implant, TIPS dilation or OLT, 3 out of 5 patients on conservative treatment experienced recurrence of VB within 9 days after SEMS removal. Conclusions: SEMS placement sufficiently stops hemorrhage in refractory VB. Due to the high rebleeding rate after conservative treatment alone following SEMS removal, this procedure may be utilized as a mere bridging method. Additional interventional and/or surgical methods to effectively reduce portal pressure (i.e. TIPS, OLT) should be considered. Further studies to evaluate the optimum treatment algorithm of refractory esophageal VB are warranted.


Liver International | 2007

Apoptosis versus necrosis rate as a predictor in acute liver failure following acetaminophen intoxication compared with acute-on-chronic liver failure.

Lars P. Bechmann; Guido Marquitan; Christoph Jochum; Fuat H. Saner; Guido Gerken; Ali Canbay

Cell death is known to play a crucial role in liver diseases. We compared the clinical courses of two cases of liver failure of different origins correlated with the extent of cell death (apoptosis and/or necrosis), measured in the patients blood. Patient 1 was admitted with acute liver failure following acetaminophen intoxication. Intravenous therapy with acetylcysteine was performed. The percentage of apoptotic cell death measured by M30 was three times higher than normal and the overall cell death measured by M65 was more than 30 × higher than normal. High levels of aminotransferases were detected, indicating high rates of necrosis. M30 and M65 values rapidly returned to normal levels, while the liver function test (LFT) levels decreased with latency. Patient 2 was admitted with acute‐on‐chronic liver failure with known liver fibrosis. M30 values were 16 × higher than normal. In contrast, M65 values were lower than in the first case. This time, no movement in M30 levels was seen until the M30 levels rapidly increased indicating the inevitable death of the patient, while LFTs did not change. These results indicate the role of M30 and M65 immunoexpression as markers for functioning liver cell mass, capacity for recovery and therefore as predictive markers in acute liver failure.


Liver Transplantation | 2006

Quantitative liver function tests in donors and recipients of living donor liver transplantation

Christoph Jochum; Mechthild Beste; Volker Penndorf; Marjan Sharifi Farahani; Giuliano Testa; Silvio Nadalin; Massimo Malago; Christoph E. Broelsch; Guido Gerken

The unique ability of the liver to regenerate quickly after resection makes living donor liver transplantation (LDLT) possible. This technique uses the unique ability of the liver to regenerate to full size after partial resection. However, the quality and course of this regeneration process in humans are still widely unexplored. In the present study we investigated the quantitative liver function tests galactose elimination capacity (GEC), indocyanine green half‐life (ICG), and lidocaine half‐life as markers for the quality of the liver regeneration in the first 3 months after LDLT. In this study, 22 consecutive living liver donors and their corresponding recipients were analyzed at baseline and at 10 and 90 days after LDLT. Six recipients lost their grafts during the study period. We compared donors and recipients at the different time points. After LDLT, GEC decreased (−42.6%) and ICG increased (+50.6%) significantly in donors. ICG and GEC remained significantly altered over 3 months in donors with an improvement between days 10 and 90 (GEC, +59.3%; ICG, −9.1%). ICG and GEC improved significantly in recipients between days 10 and 90 (ICG, −63.7%; GEC, +16.3%). The lidocaine half‐life showed no significant changes. The donors had better test results and recovered faster than the recipients. In conclusion, after LDLT the parameters for liver capacity and flow remain altered in donors and recipients despite rapid volume growth. Liver Transpl 12:544–549, 2006.

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Guido Gerken

University of Duisburg-Essen

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Ali Canbay

Otto-von-Guericke University Magdeburg

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Lars P. Bechmann

University of Duisburg-Essen

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Fuat H. Saner

University of Duisburg-Essen

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Andreas Paul

University of Duisburg-Essen

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Joerg Timm

University of Duisburg-Essen

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Alexander Dechêne

University of Duisburg-Essen

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Alisan Kahraman

University of Duisburg-Essen

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Martin Schlattjan

University of Duisburg-Essen

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