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Dive into the research topics where Anca Zimmermann is active.

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Featured researches published by Anca Zimmermann.


Transplant International | 2007

Efficacy of an escalating dose regimen of pegylated interferon α-2a plus ribavirin in the early phase of HCV reinfection after liver transplantation

Tim Zimmermann; Wulf O. Böcher; Stefan Biesterfeld; Anca Zimmermann; Stefan Kanzler; Gertrud Greif-Higer; Ana Paula Barreiros; Mf Sprinzl; Marcus A. Wörns; Ansgar W. Lohse; Christian Mönch; Gerd Otto; Peter R. Galle; Marcus Schuchmann

We evaluated the safety and efficacy of an escalating dose regimen of pegylated interferon α‐2a (PEG‐IFNα‐2a) and ribavirin in the early phase of recurrent hepatitis C after orthotopic liver transplantation (OLT). In this prospective study, 26 patients transplanted for hepatitis C virus cirrhosis with recurrent hepatitis C were treated 3.4 ± 3.6 months after OLT and compared with an untreated historical control. PEG‐IFNα‐2a was initiated as monotherapy, following stepwise dose escalation up to 180 μg/week and the addition of ribavirin up to 1200 mg/day or maximally tolerated doses for 48 weeks. In the intent‐to‐treat analysis, 38% showed an early virological response (EVR), 35% an end of treatment response (ETR) and 19% a sustained virological response (SVR). SVR was associated with EVR (P = 0.0001) and cumulative PEG‐IFNα‐2a dose (P = 0.04). There was no significant histological improvement compared with untreated patients. There were no treatment‐related serious adverse events. Adverse events included leucopenia (77%) and thrombocytopenia (46%). Three patients discontinued therapy due to side effects, fourteen were nonresponders and four relapsers. Treatment with PEG‐IFNα‐2a and ribavirin in the acute phase of post‐transplant recurrent hepatitis C yielded an EVR of 38% and an SVR of 19%. The combination was safe and well tolerated.


BMC Cancer | 2012

Downregulation of organic cation transporters OCT1 (SLC22A1) and OCT3 (SLC22A3) in human hepatocellular carcinoma and their prognostic significance

Michael Heise; Anja Lautem; Johanna Knapstein; Jörn M. Schattenberg; M. Hoppe-Lotichius; Daniel Foltys; Nina Weiler; Anca Zimmermann; Arno Schad; Dirk Gründemann; Gerd Otto; Peter R. Galle; Marcus Schuchmann; Tim Zimmermann

BackgroundOrganic cation transporters (OCT) are responsible for the uptake and intracellular inactivation of a broad spectrum of endogenous substrates and detoxification of xenobiotics and chemotherapeutics. The transporters became pharmaceutically interesting, because OCTs are determinants of the cytotoxicity of platin derivates and the transport activity has been shown to correlate with the sensitivity of tumors towards tyrosine kinase inhibitors. No data exist about the relevance of OCTs in hepatocellular carcinoma (HCC).MethodsOCT1 (SLC22A1) and OCT3 (SLC22A3) mRNA expression was measured in primary human HCC and corresponding non neoplastic tumor surrounding tissue (TST) by real time PCR (n = 53). Protein expression was determined by western blot analysis and immunofluorescence. Data were correlated with the clinicopathological parameters of HCCs.ResultsReal time PCR showed a downregulation of SLC22A1 and SLC22A3 in HCC compared to TST (p ≤ 0.001). A low SLC22A1 expression was associated with a worse patient survival (p < 0.05). Downregulation was significantly associated with advanced HCC stages, indicated by a higher number of T3 tumors (p = 0.025) with a larger tumor diameter (p = 0.035), a worse differentiation (p = 0.001) and higher AFP-levels (p = 0.019). In accordance, SLC22A1 was less frequently downregulated in tumors with lower stages who underwent transarterial chemoembolization (p < 0.001) and liver transplantation (p = 0.001). Tumors with a low SLC22A1 expression (< median) showed a higher SLC22A3 expression compared to HCC with high SLC22A1 expression (p < 0.001). However, there was no significant difference in tumor characteristics according to the level of the SLC22A3 expression.In the western blot analysis we found a different protein expression pattern in tumor samples with a more diffuse staining in the immunofluorescence suggesting that especially OCT1 is not functional in advanced HCC.ConclusionThe downregulation of OCT1 is associated with tumor progression and a worse patient survival.


Hormone Research in Paediatrics | 2010

Alterations in Lipid and Carbohydrate Metabolism in Patients with Classic Congenital Adrenal Hyperplasia due to 21-Hydroxylase Deficiency

Anca Zimmermann; Paula Grigorescu-Sido; Camelia Al-Khzouz; Karen Patberg; Simona Bucerzan; Egbert Schulze; Tim Zimmermann; Heidi Rossmann; Hans-Christian Geiss; Karl J. Lackner; Matthias M. Weber

Background: Classic 21-hydroxylase deficiency (21HD) presents some traits of the metabolic syndrome. Aim: To characterize discrete alterations of lipid and carbohydrate metabolism in children and young adults with classic 21HD, which could predict early atherogenesis. Patients and Methods: Twenty-seven Caucasian patients with classic 21HD (4–31 years); 27 sex-, age- and BMI-matched controls. Clinical parameters, hormonal status and genotype were assessed in all patients. Lipid parameters, including relative (%) and absolute (mg/dl) small-dense low-density lipoproteins subfractions (sd-LDL) were measured in patients and controls. Oral glucose tolerance tests were performed in both groups. Results: sd-LDL (%) was significantly higher in patients than controls (39.7 ± 5.9 vs. 35.5 ± 5.7%; p = 0.008). The same applies for absolute sd-LDL (mg/dl) (42.6 ± 11.9 vs. 36.4 ± 7.5; p = 0.029). HDL-cholesterol was lower in patients (p = 0.032). Fasting glucose and insulin were significantly higher in patients. Similar differences were noticed for HOMA-IR (p = 0.001), IRI (p = 0.001) and HOMA-B (p = 0.002). IRI correlated directly and significantly with the total hydrocortisone dose and the duration of treatment. Fasting glucose correlated with absolute sd-LDL. No obvious differences were seen between clinical forms or genotype groups. Conclusions: Substitution therapy should be adapted particularly at young ages to prevent early atherogenesis and cardiovascular risk in later life.


European Journal of Internal Medicine | 2010

Liver transplanted patients with preoperative autoimmune hepatitis and immunological disorders are at increased risk for Post-Transplant Lymphoproliferative Disease (PTLD).

Tim Zimmermann; M. Hoppe-Lotichius; Vuk Tripkovic; Ana Paula Barreiros; Thomas C. Wehler; Anca Zimmermann; Jörn M. Schattenberg; Michael Heise; Stefan Biesterfeld; Peter R. Galle; Gerd Otto; Marcus Schuchmann

BACKGROUND Long term immunosuppression and therapy of acute rejections result in a 20-120-fold increased risk to develop Non Hodgkin lymphoma (NHL). Since immunosuppressive therapy and immunological disorders are major risk factors for the development of NHL in the non-transplant population we aimed to analyze risk factors for PTLD in our cohort of liver transplanted (LT) patients. METHODS We analyzed retrospectively 431 patients liver transplanted between 1998 and 2008. RESULTS PTLD was diagnosed in eleven of 431 patients (2.6%). PTLD, especially late PTLD, was significantly more frequent in patients who received steroids before LT (Kaplan-Meier: p<0.001). Moreover PTLD in immunocompromised patients with preoperative steroid treatment occurred at a significantly younger age (49.5+/-4.7 years) compared to patients without steroids (60.6+/-5.1 years; p=0.006). Multivariate analysis revealed pretransplant steroid treatment and liver transplantation for autoimmune hepatitis as main risk factors for the development of PTLD after liver transplantation (p<0.001). CONCLUSION Liver transplanted patients who received steroids before LT due to immunological disorders and patients with autoimmune hepatitis seem to be at particular high risk to develop PTLD. Prospective cohort studies including immunoepidemiologic investigations of abnormalities of cellular, humoral and innate immunity should be carried out to identify predictive factors and patients at risk.


European Journal of Internal Medicine | 2011

Alterations in lipid, carbohydrate and iron metabolism in patients with non-alcoholic steatohepatitis (NASH) and metabolic syndrome

Anca Zimmermann; Tim Zimmermann; Jörn M. Schattenberg; Sebastian Pöttgen; Johannes Lotz; Heidi Rossmann; Ralf Roeddiger; Stefan Biesterfeld; Hans-Christian Geiss; Marcus Schuchmann; Peter R. Galle; Matthias M. Weber

BACKGROUND NASH (non-alcoholic steatohepatitis) is considered the hepatic manifestation of the metabolic syndrome (MS). We aimed to analyze lipid, carbohydrate, and iron metabolism in NASH. PATIENTS, METHODS 37 patients with MS (17 M/20 F, 51+/-15 years), elevated transaminases; 25 patients had histologically proven NASH (NAS score≥5), 12 patients had toxic background (nonNASH). 37 age, sex, BMI-matched healthy controls. Lipid variables, LDL-subfractions, iron, ferritin, transferrin (T), transferrin saturation (TS), and hepcidin (H) were measured in patients/controls. Oral glucose tolerance tests were performed. RESULTS NASH patients with steatosis gr. 2 and 3 (>33% hepatic fat) had higher sd-LDL (mg/dl) concentrations than patients with steatosis gr. 1 (<33%) (p=0.002), nonNASH patients (p=0.03) and controls (p=0.001). Sd absolute (mg/dl) correlated directly with the steatosis grade only in patients with NASH and steatosis >33% (p=0.04). NASH-patients showed higher insulin, C-peptide and IRI values than nonNASH patients (p=0.034; 0.032; 0.04). H was increased in patients versus controls (p<0.001). H correlated with ferritin in MS-patients (p=0.01), correlated directly with sd-LDL (mg/dl) (p=0.017) and IRI (p<0.001) and indirectly with HDL (p=0.05) in NASH. No associations between hepatic inflammation/iron content on liver biopsy and variables of lipid metabolism were found but hepcidin correlated with hepatic inflammation in all patients and with NAS scores in NASH. CONCLUSIONS NASH-patients show insulin resistance and increased sd-LDL subfractions, suggesting an atherogenic profile. The correlation of H with sd-LDL and IRI, without relation to hepatic iron content suggests a putative link between inflammation, carbohydrate and lipid metabolism in NASH.


Clinical Endocrinology | 2009

Bone mineral density and bone turnover in Romanian children and young adults with classical 21‐hydroxylase deficiency are influenced by glucocorticoid replacement therapy

Anca Zimmermann; Paula Grigorescu Sido; Egbert Schulze; Camelia Al Khzouz; Cecilia Lazea; Cristina Coldea; Matthias M. Weber

Objective  It remains controversial if glucocorticoid replacement therapy impairs bone mineral density (BMD) in young patients with 21‐hydroxylase deficiency. We aimed to analyze the impact of treatment variables, phenotype and genotype on BMD and bone metabolism in these patients.


Digestive and Liver Disease | 2016

Early changes in dynamic biomarkers of liver fibrosis in hepatitis C virus-infected patients treated with sofosbuvir

Sebastian Bernuth; Detlef Schuppan; Mf Sprinzl; Anca Zimmermann; Arno Schad; Jens M. Kittner; Veronika Weyer; Johanna Knapstein; Jörn M. Schattenberg; Marcus A. Wörns; Peter R. Galle; Tim Zimmermann

BACKGROUND Chronic hepatitis C is a major cause of liver-associated mortality caused by decompensated cirrhosis and hepatocellular carcinoma. With the approval of sofosbuvir, therapeutic efficacy has markedly increased. Early changes in non-invasive biomarkers of liver fibrosis under effective antiviral therapy are widely unknown. AIM To evaluate early changes of fibrosis markers determined by enhanced liver fibrosis (ELF) scores and liver stiffness measurement (FibroScan(®)) in patients treated with sofosbuvir. METHODS A total of 32 hepatitis C patients treated prospectively with sofosbuvir were included. The ELF-panel and FibroScan measurements were performed at baseline, week 4, end-of-treatment and 12 weeks thereafter. RESULTS Antiviral therapy resulted in a biochemical and virological response within 4 weeks. Sustained virological response rate at 12-week follow-up (SVR12) was 93.8%; there was a significantly decrease from baseline to 12-week post-treatment follow-up in ELF (10.00 vs. 9.37; p=0.007) and FibroScan (8.0 vs. 6.8 kPa; p=0.016) measurements, indicating improvement of the dynamics of liver fibrosis. CONCLUSION We observed a rapid decrease in non-invasive fibrosis markers measured by ELF-scores and FibroScan in hepatitis C-infected patients receiving sofosbuvir treatment. These initial results need to be histologically confirmed by liver biopsy in the future.


International Journal of Oncology | 2013

Downregulation of organic cation transporter 1 (SLC22A1) is associated with tumor progression and reduced patient survival in human cholangiocellular carcinoma

Anja Lautem; Michael Heise; Andreas Gräsel; M. Hoppe-Lotichius; Nina Weiler; Daniel Foltys; Johanna Knapstein; Jörn M. Schattenberg; Arno Schad; Anca Zimmermann; Gerd Otto; Hauke Lang; Peter R. Galle; Marcus Schuchmann; Tim Zimmermann

Cholangiocellular carcinoma (CCA) is a primary hepatic malignancy derived from cholangiocytes. The prognosis for CCA patients is very poor and conventional chemotherapy has been proven ineffective in improving long‑term patient survival rates. Organic cation transporters (OCTs) mediate the transport of a broad spectrum of endogenous substrates and the detoxification of xenobiotics. Moreover, OCTs are considered responsible for the responsiveness towards platinum‑based chemotherapies. Currently, there are no data available regarding the role of OCTs in CCA. Therefore, the aim of this study was to investigate the expression of OCT1 and OCT3 in CCA and the corresponding non-neoplastic tumor‑surrounding tissue (TST). OCT1 (SLC22A1) and OCT3 (SLC22A3) mRNA expression was measured in primary human CCA by real-time PCR (n=27). Protein expression was determined by western blot analysis and immunohistochemistry. Data were correlated with the clinicopathological parameters of CCA. Real-time PCR demonstrated a downregulation of the expression of SLC22A1 and SLC22A3 in CCA, compared to that in TST (p<0.001). A low SLC22A1 expression was associated with a worse patient survival (p<0.05). The downregulation of SLC22A1 was significantly associated with advanced CCA stages, since tumors with a low SLC22A1 mRNA expression presented with larger tumor diameters (p=0.02). There were no significant differences in tumor characteristics or patient survival in relation to the level of SLC22A3 expression. Western blot analysis and immunohistochemistry confirmed the downregulation of OCT1 and OCT3 protein levels in cancerous tissue compared to those in TST. In conclusion, the downregulation of OCT1 is associated with tumor progression and worse overall patient survival rates.


Transplantation Proceedings | 2009

Risk Factors in Patients With Rapid Recurrent Hepatitis C Virus–Related Cirrhosis Within 1 Year After Liver Transplantation

Tim Zimmermann; C. Otto; M. Hoppe-Lotichius; Stefan Biesterfeld; Anja Lautem; M. Knaak; Anca Zimmermann; Ana Paula Barreiros; Michael Heise; Jörn M. Schattenberg; Mf Sprinzl; Peter R. Galle; Gerd Otto; Marcus Schuchmann

BACKGROUND Recurrent cirrhosis (RC) due to pretransplant underlying disease leads to organ failure and subsequent death after orthotopic liver transplantation (OLT). RC occurs in up to 30% of patients with recurrent hepatitis C (HCV) within 5 years after OLT. We sought to identify early risk factors for rapid RC within the first year after OLT in HCV-positive patients. METHODS Among 404 liver transplanted patients at the University of Mainz between 1998 and 2008, 90 were HCV-RNA positive. To identify predictive factors for rapid RC, we compared HCV-positive patients with advanced fibrosis stages within 1 year after OLT (n = 13) with these without RC at 5 years after OLT (n = 23). RESULTS Overall, poorer patient survival was associated with advanced fibrosis scores in the 1-year protocol biopsy and nonresponse to interferon treatment before OLT. The strongest predictive factors for rapid RC were persistently high levels of alkaline phosphatase, bilirubin, viral load at 6 months after OLT, and multiple steroid pulse therapies. The CCR2-V64I polymorphism was not associated with rapid RC. CONCLUSION We presented a group of patients with HCV-related rapid RC within the first year after OLT to identify predictive factors for rapid fibrosis progression.


Journal of Pediatric Endocrinology and Metabolism | 2007

MRI findings and genotype analysis in patients with childhood onset growth hormone deficiency : Correlation with severity of hypopituitarism

Anca Zimmermann; J.-P. Schenk; P. Grigorescu Sido; R. Pfäffle; Cecilia Lazea; Tim Zimmermann; U. Heinrich; Matthias M. Weber; M. Bettendorf

AIM To evaluate the relationship between pituitary size, PIT1 and PROP1 genotype, and the severity of childhood onset growth hormone deficiency (coGHD). PATIENTS Forty-four patients with coGHD (34 M; 9.7 +/- 4.1 years): severe isolated (SI) GHD (n = 14); partial isolated (PI) GHD (n=13); multiple pituitary hormone deficiencies (MPHD) (n=17). RESULTS Pituitary abnormalities were found in 7/14 patients with SIGHD (50%), 16/17 patients with MPHD (94.1%), and no patient with PIGHD. Mean pituitary height (PHT SDS) was significantly lower in MPHD than in SIGHD and PIGHD. Pituitary height SDS and pituitary volume (PV) SDS correlated with IGF-I SDS and stimulated GH peaks in the SIGHD and MPHD groups. No PIT1 mutation was identified. The PROP1 AG deletion (301-302) was present in five related patients with MPHD and more severe phenotype than the other patients with MPHD. CONCLUSIONS Pituitary abnormalities corresponded to the severity of coGHD. Genetic alterations were identified in five related patients with MPHD.

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Simona Bucerzan

Boston Children's Hospital

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