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Dive into the research topics where Thomas Reiberger is active.

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Featured researches published by Thomas Reiberger.


Gut | 2013

Carvedilol for primary prophylaxis of variceal bleeding in cirrhotic patients with haemodynamic non-response to propranolol

Thomas Reiberger; Gregor Ulbrich; Arnulf Ferlitsch; Ba Payer; P Schwabl; Matthias Pinter; Birgit Heinisch; Michael Trauner; Ludwig Kramer; Markus Peck-Radosavljevic; Vienna Hepatic Hemodynamic Lab

Objective Non-selective β-blockers or endoscopic band ligation (EBL) are recommended for primary prophylaxis of variceal bleeding in patients with oesophageal varices. Additional α-adrenergic blockade (as by carvedilol) may increase the number of patients with haemodynamic response (reduction in hepatic venous pressure gradient (HVPG) of ≥20% or to values <12 mm Hg). Design Patients with oesophageal varices undergoing measurement of HVPG before and under propranolol treatment (80–160 mg/day) were included. HVPG responders were kept on propranolol (PROP group), while non-responders were placed on carvedilol (6.25–50 mg/day). Carvedilol responders continued treatment (CARV group), while non-responders to carvedilol underwent EBL. The primary aim was to assess haemodynamic response rates to carvedilol in propranolol non-responders. Results 36% (37/104) of patients showed a HVPG response to propranolol. Among the propranolol non-responders 56% (38/67) eventually achieved a haemodynamic response with carvedilol, while 44% (29/67) patients were finally treated with EBL. The decrease in HVPG was significantly greater with carvedilol (median 12.5 mg/day) than with propranolol (median 100 mg/day): −19±10% versus −12±11% (p<0.001). During a 2 year follow-up bleeding rates for PROP were 11% versus CARV 5% versus EBL 25% (p=0.0429). Fewer episodes of hepatic decompensation (PROP 38%/CARV 26% vs EBL 55%; p=0.0789) and significantly lower mortality (PROP 14%/CARV 11% vs EBL 31%; p=0.0455) were observed in haemodynamic responders compared to the EBL group. Conclusions Carvedilol leads to a significantly greater decrease in HVPG than propranolol. Using carvedilol for primary prophylaxis a substantial proportion of non-responders to propranolol can achieve a haemodynamic response, which is associated with improved outcome with regard to prevention of variceal bleeding, hepatic decompensation and death.


Journal of Hepatology | 2013

Non-selective betablocker therapy decreases intestinal permeability and serum levels of LBP and IL-6 in patients with cirrhosis

Thomas Reiberger; Arnulf Ferlitsch; Ba Payer; Mattias Mandorfer; Birgit Heinisch; Hubert Hayden; Frank Lammert; Michael Trauner; Markus Peck-Radosavljevic; Harald Vogelsang

BACKGROUND & AIMS We evaluated the gastrointestinal permeability and bacterial translocation in cirrhotic patients with portal hypertension (PHT) prior to and after non-selective betablocker (NSBB) treatment. METHODS Hepatic venous pressure gradient (HVPG) was measured prior to and under NSBB treatment. Gastroduodenal and intestinal permeability was assessed by the sucrose-lactulose-mannitol (SLM) test. Anti-gliadin and anti-endomysial antibodies were measured. Levels of LPS-binding protein (LBP) and interleukin-6 (IL-6) were quantified by ELISA, and NOD2 and toll-like receptor 2 (TLR2) polymorphisms were genotyped. RESULTS Fifty cirrhotics were included (72% male, 18% ascites, 60% alcoholic etiology). Abnormal gastroduodenal and intestinal permeability was found in 72% and 59% of patients, respectively. Patients with severe portal hypertension (HVPG ≥20 mm Hg; n=35) had increased markers of gastroduodenal/intestinal permeability (urine sucrose levels p=0.049; sucrose/mannitol ratios p=0.007; intestinal permeability indices p=0.002), and bacterial translocation (LBP p=0.002; IL-6 p=0.025) than patients with HVPG <20 mm Hg. A substantial portion of patients showed elevated levels of anti-gliadin antibodies (IgA: 60%, IgG: 34%) whereas no anti-endomysial antibodies were detected. A significant correlation of portal pressure (i.e., HVPG) with all markers of gastroduodenal/intestinal permeability and with LBP and IL-6 levels was observed. NOD2 and TLR2 risk variants were associated with abnormal intestinal permeability and elevated markers of bacterial translocation. At follow-up HVPG measurements under NSBB, we found an amelioration of gastroduodenal/intestinal permeability and a decrease of bacterial translocation (LBP - 16% p=0.018; IL-6 - 41% p<0.0001) levels, which was not limited to hemodynamic responders. Abnormal SLM test results and higher LBP/IL-6 levels were associated with a higher risk of variceal bleeding during follow-up but not with mortality. CONCLUSIONS Abnormal gastroduodenal/intestinal permeability, anti-gliadin antibodies, and bacterial translocation are common findings in cirrhotic patients and are correlated with the degree of portal hypertension. NSBB treatment ameliorates gastroduodenal/intestinal permeability and reduces bacterial translocation partially independent of their hemodynamic effects on portal pressure, which may contribute to a reduced risk of variceal bleeding.


Hepatology | 2012

Von Willebrand factor as new noninvasive predictor of portal hypertension, decompensation and mortality in patients with liver cirrhosis

Monika Ferlitsch; Thomas Reiberger; Matthias Hoke; Petra Salzl; Bernadette Schwengerer; Gregor Ulbrich; Ba Payer; Michael Trauner; Markus Peck-Radosavljevic; Arnulf Ferlitsch

von Willebrand factor antigen (vWF‐Ag) is elevated in patients with liver cirrhosis, but the clinical significance is unclear. We hypothesized that vWF‐Ag levels may correlate with portal pressure, measured by hepatic venous pressure gradient (HVPG), and predict clinically significant portal hypertension (CSPH; HVPG ≥10 mmHg), decompensation and mortality. Portal hemodynamics were assessed by HVPG measurement, whereas vWF‐Ag levels were measured by enzyme‐linked immunosorbent assay. During follow‐up, complications of liver cirrhosis, death or transplantation were recorded. Two hundred and eighty‐six patients (205 male and 81 female; mean age, 56 years) with liver cirrhosis were included. vWF‐Ag correlated with HVPG (r = 0.69; P < 0.0001) and predicted CSPH independently of Child Pugh score. Higher vWF‐Ag levels were associated with varices (odds ratio [OR] = 3.27; P < 0.001), ascites (OR = 3.93; P < 0.001) and mortality (hazard ratio: 4.41; P < 0.001). Using a vWF‐Ag cut‐off value of ≥241%, the AUC for detection of CSPH in compensated patients was 0.85, with a positive predictive value and negative predictive value of 87% and 80%, respectively. Compensated patients had 25% mortality after 53 months if the vWF‐Ag was <315% compared to 15 months in patients with vWF‐Ag >315% (P < 0.001). Decompensated patients had a mortality of 25% after 37 and 7 months if their vWF‐Ag was <315% and >315%, respectively (P = 0.002). In compensated patients with a vWF‐Ag >315% median time to decompensation or death was 32 months compared with 59 months in patients with vWF‐Ag <315%. vWF‐Ag equals Model for End‐Stage Liver Disease (MELD) in mortality prediction (area under the curve [AUC] = 0.71 for vWF‐Ag versus AUC = 0.65 for MELD; P = 0.2). Conclusion: vWF‐Ag is a new, simple and noninvasive predictor of CSPH. A vWF‐Ag cut–off value at 315% can clearly stratify patients with compensated and decompensated liver cirrhosis in two groups with completely different survival. vWF‐Ag may become a valuable marker for the prediction of mortality in patients with liver cirrhosis in clinical practice. (HEPATOLOGY 2012)


Hepatology | 2014

Differential effects of sorafenib on liver versus tumor fibrosis mediated by stromal‐derived factor 1 alpha/C‐X‐C receptor type 4 axis and myeloid differentiation antigen–positive myeloid cell infiltration in mice

Yunching Chen; Yuhui Huang; Thomas Reiberger; Annique M. Duyverman; Peigen Huang; Rekha Samuel; Lotte Hiddingh; Sylvie Roberge; Christina Koppel; Gregory Y. Lauwers; Andrew X. Zhu; Rakesh K. Jain; Dan G. Duda

Sorafenib—a broad kinase inhibitor—is a standard therapy for advanced hepatocellular carcinoma (HCC) and has been shown to exert antifibrotic effects in liver cirrhosis, a precursor of HCC. However, the effects of sorafenib on tumor desmoplasia—and its consequences on treatment resistance—remain unknown. We demonstrate that sorafenib has differential effects on tumor fibrosis versus liver fibrosis in orthotopic models of HCC in mice. Sorafenib intensifies tumor hypoxia, which increases stromal‐derived factor 1 alpha (SDF‐1α) expression in cancer and stromal cells and, subsequently, myeloid differentiation antigen–positive (Gr‐1+) myeloid cell infiltration. The SDF‐1α/C‐X‐C receptor type 4 (CXCR4) pathway directly promotes hepatic stellate cell (HSC) differentiation and activation through the mitogen‐activated protein kinase pathway. This is consistent with the association between SDF‐1α expression with fibrotic septa in cirrhotic liver tissues as well as with desmoplastic regions of human HCC samples. We demonstrate that after treatment with sorafenib, SDF‐1α increased the survival of HSCs and their alpha‐smooth muscle actin and collagen I expression, thus increasing tumor fibrosis. Finally, we show that Gr‐1+ myeloid cells mediate HSC differentiation and activation in a paracrine manner. CXCR4 inhibition, using AMD3100 in combination with sorafenib treatment, prevents the increase in tumor fibrosis—despite persistently elevated hypoxia—in part by reducing Gr‐1+ myeloid cell infiltration and inhibits HCC growth. Similarly, antibody blockade of Gr‐1 reduces tumor fibrosis and inhibits HCC growth when combined with sorafenib treatment. Conclusion: Blocking SDF‐1α/CXCR4 or Gr‐1+ myeloid cell infiltration may reduce hypoxia‐mediated HCC desmoplasia and increase the efficacy of sorafenib treatment. (Hepatology 2014;59:1435‐1447)


Journal of Hepatology | 2009

Sorafenib attenuates the portal hypertensive syndrome in partial portal vein ligated rats

Thomas Reiberger; Bernhard Angermayr; P Schwabl; Natascha Rohr-Udilova; Markus Mitterhauser; Alfred Gangl; Markus Peck-Radosavljevic

BACKGROUND/AIMS Angiogenesis plays a key role in development of portal hypertension (PHT) and represents a potential therapeutic target. We aimed to evaluate the molecular effects of sorafenib, a multiple tyrosine kinase inhibitor, on splanchnic hemodynamics in rats with partial portal vein ligation (PPVL). METHODS The following four groups of rats were treated orally with sorafenib (10mg/kg per day; SORA group) or placebo (PLAC group) for 7 days, beginning at the day of PPVL or sham operation (SO): (1) PPVL-SORA, (2) PPVL-PLAC, (3) SO-SORA and (4) SO-PLAC. Measurements of mean arterial pressure (MAP), portal pressure (PP), and superior mesenterial artery blood flow (SMABF) were performed. Portosystemic collateral blood flow (PSCBF) was determined by radioactive microspheres. Splanchnic protein expression of CD31, alpha-smooth muscle actin (alphaSMA), phospho-extracellular signal-regulated kinase (pERK), vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), tumor necrosis factor alpha (TNFalpha), and endothelial nitric oxide synthetase (eNOS) was assessed by Western blot. Gene expression was studied by angiogenesis-focused real-time reverse transcription polymerase chain reaction microarray. RESULTS PP, SMABF, and PSCBF were significantly higher in PPVL rats than in SO rats. MAP and heart rate were similar in all groups. Treatment with sorafenib resulted in a significant decrease of PP (p<0.001) and SMABF (p<0.05) in PPVL-SORA rats compared to PPVL-PLAC rats. PPVL-SORA rats had markedly less PSCBF than PPVL-PLAC rats (p<0.001). Superior mesenteric artery resistance (SMAR) was significantly lower in both PPVL groups compared to both SO groups, but PPVL-SORA rats showed significantly higher SMAR than PPVL-PLAC rats (p<0.05). The increased protein expression of CD31, alphaSMA, pERK, VEGF, PDGF, TNFalpha, and eNOS in rats with PHT was markedly decreased by sorafenib treatment. Sorafenib decreased mRNA levels of TNFalpha, VEGF receptor 2, VEGF receptor 1, transforming growth factor beta, cyclooxygenase 1, and expression of various genes that are involved in pathways of cellular proliferation, fibrogenesis, tissue remodeling, inflammation, and angiogenesis. CONCLUSIONS Treatment with sorafenib reduced PP, SMABF, and PSCBF in noncirrhotic rats with prehepatic PHT, without affecting systemic hemodynamics. Additional antiproliferative, anti-inflammatory, and antiangiogenic effects of sorafenib were identified.


Journal of Hepatology | 2016

Sustained virologic response to interferon-free therapies ameliorates HCV-induced portal hypertension

Mattias Mandorfer; K. Kozbial; P Schwabl; C. Freissmuth; Remy Schwarzer; R. Stern; D Chromy; Albert Friedrich Stättermayer; Thomas Reiberger; Sandra Beinhardt; Wolfgang Sieghart; Michael Trauner; Harald Hofer; Arnulf Ferlitsch; Peter Ferenci; Markus Peck-Radosavljevic

BACKGROUND & AIMS We aimed to investigate the impact of sustained virologic response (SVR) to interferon (IFN)-free therapies on portal hypertension in patients with paired hepatic venous pressure gradient (HVPG) measurements. METHODS One hundred and four patients with portal hypertension (HVPG ⩾6mmHg) who underwent HVPG and liver stiffness measurement before IFN-free therapy (baseline [BL]) were retrospectively studied. Among 100 patients who achieved SVR, 60 patients underwent HVPG and transient elastography (TE) after antiviral therapy (follow-up [FU]). RESULTS SVR to IFN-free therapies significantly decreased HVPG across all BL HVPG strata: 6-9mmHg (BL: 7.37±0.28 vs. FU: 5.11±0.38mmHg; -2.26±0.42mmHg; p<0.001), 10-15mmHg (BL: 12.2±0.4 vs. FU: 8.91±0.62mmHg; -3.29±0.59mmHg; p<0.001) and ⩾16mmHg (BL: 19.4±0.73 vs. FU: 17.1±1.21mmHg; -2.3±0.89mmHg; p=0.018). In the subgroup of patients with BL HVPG of 6-9mmHg, HVPG normalized (<6mmHg) in 63% (12/19) of patients, while no patient progressed to ⩾10mmHg. Among patients with BL HVPG ⩾10mmHg, a clinically relevant HVPG decrease ⩾10% was observed in 63% (26/41); 24% (10/41) had a FU HVPG <10mmHg. Patients with Child-Pugh stage B were less likely to have a HVPG decrease (hazard ratio [HR]: 0.103; 95% confidence interval [CI]: 0.02-0.514; p=0.006), when compared to Child-Pugh A patients. In the subgroup of patients with BL CSPH, the relative change in liver stiffness (per %; HR: 0.972; 95% CI: 0.945-0.999; p=0.044) was a predictor of a HVPG decrease ⩾10%. The area under the receiver operating characteristic curve for the diagnosis of FU CSPH by FU liver stiffness was 0.931 (95% CI: 0.865-0.997). CONCLUSIONS SVR to IFN-free therapies might ameliorate portal hypertension across all BL HVPG strata. However, changes in HVPG seemed to be more heterogeneous among patients with BL HVPG of ⩾16mmHg and a HVPG decrease was less likely in patients with more advanced liver dysfunction. TE might be useful for the non-invasive evaluation of portal hypertension after SVR. LAY SUMMARY We investigated the impact of curing hepatitis C using novel interferon-free treatments on portal hypertension, which drives the development of liver-related complications and mortality. Cure of hepatitis C decreased portal pressure, but a decrease was less likely among patients with more pronounced hepatic dysfunction. Transient elastography, which is commonly used for the non-invasive staging of liver disease, might identify patients without clinically significant portal hypertension after successful treatment.


Liver International | 2015

New reliability criteria for transient elastography increase the number of accurate measurements for screening of cirrhosis and portal hypertension

P Schwabl; Simona Bota; Petra Salzl; Mattias Mandorfer; Ba Payer; Arnulf Ferlitsch; Judith Stift; Friedrich Wrba; Michael Trauner; Markus Peck-Radosavljevic; Thomas Reiberger

Transient elastography (TE) can non‐invasively diagnose cirrhosis and portal hypertension (PHT). New TE reliability criteria suggest classifying measurements as very reliable (IQR/M < 0.1), reliable (IQR<0.3 or >0.3, if TE < 7.1 kPa) and poorly reliable (IQR/M > 0.3, if TE > 7.1 kPa). Compare traditional (reliable: success rate >60% + IQR/M ≤ 0.30) and new TE quality criteria (accurate: very reliable + reliable) regarding their diagnostic accuracy for cirrhosis and PHT and to identify potential confounders (age, aetiology, necroinflammatory activity, steatosis, siderosis, cholestasis, aminotransferases) of TE performance.


Clinical Gastroenterology and Hepatology | 2011

Portal Pressure Predicts Outcome and Safety of Antiviral Therapy in Cirrhotic Patients With Hepatitis C Virus Infection

Thomas Reiberger; Karoline Rutter; Arnulf Ferlitsch; Ba Payer; Harald Hofer; Sandra Beinhardt; Michael Kundi; Peter Ferenci; Alfred Gangl; Michael Trauner; Markus Peck–Radosavljevic

BACKGROUND & AIMS There are limited data on the efficacy and safety of antiviral therapy in patients with hepatitis C virus (HCV)-related cirrhosis, particularly on the impact of portal hypertension. METHODS We assessed hepatovenous pressure gradient (HVPG), liver stiffness (transient elastography), and interleukin (IL)-28B polymorphisms (rs12979860) in 90 cirrhotic patients with HCV infection (82% genotype 1 or 4) before antiviral therapy with pegylated interferon and ribavirin. Efficacy and safety were evaluated. RESULTS Rates of sustained virologic response were significantly lower among patients with clinically significant portal hypertension (CSPH; HVPG ≥ 10 mm Hg; n = 50) than among patients without CSPH (HVPG <10 mm Hg; n = 40): 14% vs 51% (P = .0007). Seventy-nine percent and 83% of patients with CSPH and without CSPH, respectively, received more than 80% of planned dose (P = .647). The predictive value of HVPG (area under the curve [AUC], 0.743) was greater than that of liver stiffness (AUC, 0.647) or of baseline HCV RNA levels (AUC, 0.620). The IL-28B polymorphism was not associated significantly with a sustained virologic response. Multivariate analysis revealed that HVPG (odds ratio [OR], 14.3; P = .009), baseline HCV RNA levels (OR, 5.3; P = .019), and HCV genotype (OR, 6.5; P = .046) were independent risk factors for treatment failure. A trend toward higher incidence of anemia and neutropenia was observed for patients with CSPH. The incidence and grade of thrombocytopenia were significantly higher among patients with than without CSPH (94% vs 75%; P = .006). CONCLUSIONS HVPG is an independent predictor of response to antiviral therapy, with better predictive value than liver stiffness, baseline HCV RNA levels, HCV genotype, or IL-28B polymorphism. The incidence and grade of thrombocytopenia during antiviral therapy are higher among patients with CSPH. In evaluating cirrhotic HCV patients for antiviral treatment, measurement of HVPG should be considered.


Journal of Viral Hepatitis | 2012

Five-year on-treatment efficacy of lamivudine-, tenofovir- and tenofovir + emtricitabine-based HAART in HBV-HIV-coinfected patients.

Lana Kosi; Thomas Reiberger; Ba Payer; Katharina Grabmeier-Pfistershammer; Robert Strassl; Armin Rieger; Markus Peck-Radosavljevic

Summary.  Data on the efficacy of lamivudine (LAM)‐, tenofovir (TDF)‐ and emtricitabine (FTC)‐based antiretroviral therapy (HAART) in HBV–HIV coinfection are limited. We completed a retrospective analysis of HBV–HIV‐coinfected patients treated at the Medical University of Vienna. One‐hundred and ten coinfected patients were included, with 57% being initially HBV e‐Antigen (HBeAg) positive. Baseline HBV load was significantly higher in HBeAg+ than in HBeAg− patients (5962 ± 3663 vs 20 ± 19 × 106 IU/mL; P < 0.0001). Over a median observation period of 83 month (range: 26–183), 87% received HAART and 91% showed a suppression of HBV replication. After 5 years of continuous treatment, HBeAg seroconversion was achieved in 21% of LAM‐, 50% of TDF‐ (P = 0.042 vs LAM) and in 57% of TDF + FTC (P = 0.008 vs LAM)‐treated patients, respectively. HBsAg loss after 5 years was found in 8% (LAM), 25% (TDF; P = 0.085 vs LAM) and 29% (TDF + FTC; P = 0.037 vs LAM) of HBeAg+ patients. In HBeAg− patients, HBsAg loss was achieved in 11% (LAM), 27% (TDF; P = 0.263 vs LAM) and 36% (TDF + FTC; P = 0.05 vs LAM), respectively. Pretreatment CD4+ counts did not influence rates of HBeAg seroconversion and of HBsAg loss. Patients with HBsAg loss had lower baseline HBV‐DNA levels and higher AST/ALT levels than patients without HBsAg loss. Transient HAART‐related hepatotoxicity was found in 32% (Grade I: 21%; II:7%; III:2%; IV:0%). Most HBV–HIV‐coinfected patients achieve complete suppression of HBV replication despite high baseline viremia. TDF‐based HAART leads to high rates of HBeAg seroconversion and HBsAg loss after 5 years of continuous exposure. One‐third of HBV–HIV‐coinfected patients may experience transient HAART‐related hepatotoxicity.


PLOS ONE | 2013

Suppression of HBV by Tenofovir in HBV/HIV Coinfected Patients: A Systematic Review and Meta-Analysis

Huw Price; David Dunn; Deenan Pillay; Firouze Bani-Sadr; Theodora E. M. S. de Vries-Sluijs; Mamta K. Jain; Noriyoshi Kuzushita; Stefan Mauss; Marina Núñez; Reto Nüesch; Marion G. Peters; Thomas Reiberger; Christoph Stephan; Lionel Tan; Richard Gilson

Background Hepatitis B coinfection is common in HIV-positive individuals and as antiretroviral therapy has made death due to AIDS less common, hepatitis has become increasingly important. Several drugs are available to treat hepatitis B. The most potent and the one with the lowest risk of resistance appears to be tenofovir (TDF). However there are several questions that remain unanswered regarding the use of TDF, including the proportion of patients that achieves suppression of HBV viral load and over what time, whether suppression is durable and whether prior treatment with other HBV-active drugs such as lamivudine, compromises the efficacy of TDF due to possible selection of resistant HBV strains. Methods A systematic review and meta-analysis following PRISMA guidelines and using multilevel mixed effects logistic regression, stratified by prior and/or concomitant use of lamivudine and/or emtricitabine. Results Data was available from 23 studies including 550 HBV/HIV coinfected patients treated with TDF. Follow up was for up to seven years but to ensure sufficient power the data analyses were limited to three years. The overall proportion achieving suppression of HBV replication was 57.4%, 79.0% and 85.6% at one, two and three years, respectively. No effect of prior or concomitant 3TC/FTC was shown. Virological rebound on TDF treatment was rare. Interpretation TDF suppresses HBV to undetectable levels in the majority of HBV/HIV coinfected patients with the proportion fully suppressed continuing to increase during continuous treatment. Prior treatment with 3TC/FTC does not compromise efficacy of TDF treatment. The use of combination treatment with 3TC/FTC offers no significant benefit over TDF alone.

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Mattias Mandorfer

Medical University of Vienna

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Michael Trauner

Medical University of Vienna

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P Schwabl

Medical University of Vienna

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Arnulf Ferlitsch

Medical University of Vienna

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Ba Payer

Medical University of Vienna

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Theresa Bucsics

Medical University of Vienna

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Wolfgang Sieghart

Medical University of Vienna

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B Scheiner

Medical University of Vienna

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