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Dive into the research topics where Isabella Zwiener is active.

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Featured researches published by Isabella Zwiener.


Journal of Clinical Oncology | 2010

Survival and Prognostic Factors of Early Childhood Medulloblastoma: An International Meta-Analysis

Stefan Rutkowski; Katja von Hoff; Angela Emser; Isabella Zwiener; Torsten Pietsch; Dominique Figarella-Branger; Felice Giangaspero; David W. Ellison; Maria Luisa Garrè; Veronica Biassoni; Richard Grundy; Jonathan L. Finlay; Girish Dhall; Marie Anne Raquin; Jacques Grill

PURPOSE To assess the prognostic role of clinical parameters and histology in early childhood medulloblastoma. PATIENTS AND METHODS Clinical and histologic data from 270 children younger than age 5 years diagnosed with medulloblastoma between March 1987 and July 2004 and treated within prospective trials of five national study groups were centrally analyzed. RESULTS Two hundred sixty children with medulloblastoma and specified histologic subtype were eligible for analysis (median age, 1.89 years; median follow-up, 8.0 years). Rates for 8-year event-free survival (EFS) and overall survival (OS) were 55% and 76%, respectively, in 108 children with desmoplastic/nodular medulloblastoma (DNMB) or medulloblastoma with extensive nodularity (MBEN); 27% and 42%, respectively, in 145 children with classic medulloblastoma (CMB); and 14% and 14%, respectively, in seven children with large-cell/anaplastic (LC/A) medulloblastoma (P < .001). Histology (DNMB/MBEN: hazard ratio [HR], 0.44; 95% CI, 0.31 to 0.64; LC/A medulloblastoma: HR, 2.27; 95% CI, 0.95 to 5.54; P < .001 compared with CMB), incomplete resection and metastases (M0R1: HR, 1.86; 95% CI, 1.29 to 2.80; M+: HR, 2.28; 95% CI, 1.50 to 3.46; P < .001 compared with M0R0), and national group were independent prognostic factors for EFS, and OS. The HRs for OS ranged from 0.14 for localized M0 and DNMB/MBEN to 13.67 for metastatic LC/A medulloblastoma in different national groups. CONCLUSION Our results confirm the high frequency of desmoplastic variants of medulloblastomas in early childhood and histopathology as a strong independent prognostic factor. A controlled de-escalation of treatment may be appropriate for young children with DNMB and MBEN in future clinical trials.


Neuro-oncology | 2011

Treatment of young children with localized medulloblastoma by chemotherapy alone: results of the prospective, multicenter trial HIT 2000 confirming the prognostic impact of histology.

André O. von Bueren; Katja von Hoff; Torsten Pietsch; Nicolas U. Gerber; Monika Warmuth-Metz; Frank Deinlein; Isabella Zwiener; Andreas Faldum; Gudrun Fleischhack; Martin Benesch; Juergen Krauss; Joachim Kuehl; Rolf Dieter Kortmann; Stefan Rutkowski

This study was designed to confirm the previously observed favorable survival rates and prognostic factors in young children with nonmetastatic medulloblastoma (MB) treated with postoperative chemotherapy alone. Patients who received a diagnosis during the period January 2001 through December 2005 and who were aged <4 years received 3 cycles of postoperative systemic multiagent chemotherapy and intraventricular methotrexate. In cases of complete remission, treatment was terminated after 2 additional cycles of chemotherapy. Otherwise, secondary surgery, radiotherapy, and consolidation chemotherapy were recommended. At a median follow-up of 4.5 years, the 5-year event-free survival (EFS) and overall survival (OS) rates (± standard error) for 45 patients (median age, 2.5 years) were 57% ± 8% and 80% ± 6%, respectively. Nineteen patients with desmoplastic/nodular MB variants had better 5-year EFS and OS rates (90% ± 7% and 100% ± 0%, respectively) than did 23 patients with classic MB (30% ± 11% and 68% ± 10%, respectively; P < .001 for EFS; P = .008 for OS). Five-year EFS and OS rates for 3 children with anaplastic MB were 33% ± 27%. Desmoplastic/nodular histology was an independent prognostic factor for EFS. Twenty-nine of 30 patients without postoperative residual tumor remained in continuous complete remission. Our results confirm that histology of MB variants is a strong prognostic factor in this age group. Sustained tumor control can be achieved by this chemotherapy regimen in young children with desmoplastic/nodular MB variants. For children with non-desmoplastic/nonnodular MB variants, for which predominantly local relapses lead to less favorable survival rates, local radiotherapy has been introduced after chemotherapy since 2006.


Pediatric Blood & Cancer | 2011

Frequency, risk-factors and survival of children with atypical teratoid rhabdoid tumors (AT/RT) of the CNS diagnosed between 1988 and 2004, and registered to the German HIT database.

Katja von Hoff; Bernward Hinkes; Elke Dannenmann‐Stern; André O. von Bueren; Monika Warmuth-Metz; Niels Soerensen; Angela Emser; Isabella Zwiener; Paul G. Schlegel; Joachim Kuehl; Michael C. Frühwald; Rolf Dieter Kortmann; Torsten Pietsch; Stefan Rutkowski

To analyze the frequency, prognostic factors, and outcome of children with atypical teratoid/rhabdoid tumors (AT/RT), a rare and highly malignant embryonal brain tumor.


Hormone Research in Paediatrics | 2010

Analyses of treatment variables for patients with childhood craniopharyngioma--results of the multicenter prospective trial KRANIOPHARYNGEOM 2000 after three years of follow-up.

Hermann L. Müller; Ursel Gebhardt; Sabine Schröder; Fabian Pohl; Rolf-Dieter Kortmann; Andreas Faldum; Isabella Zwiener; Monika Warmuth-Metz; Torsten Pietsch; Gabriele Calaminus; Reinhard Kolb; Christoph Wiegand; Niels Sörensen

Background: Controversies surround various treatment variables for patients with childhood craniopharyngioma such as growth hormone (GH) replacement, which some believe can exacerbate recurrence/progression. We prospectively assessed the risk of tumor recurrence/progression in survivors of childhood craniopharyngioma. Methods: Multivariable analyses of risk factors (age at diagnosis, degree of resection, irradiation, GH treatment and gender) and descriptive analyses of overall survival (OS) and event-free survival (EFS) rates were performed in 117 patients, recruited prospectively and evaluated after 3 years of follow-up in the German, Austrian and Swiss multicenter trial KRANIOPHARYNGEOM 2000. Results: We observed a 3-year OS of 0.97 and a 3-year EFS of 0.46, indicating high recurrence rates after complete resection (CR) (n = 47; 3-year-EFS: 0.64) and high progression rates after incomplete resection (IR) (n = 64; 3-year EFS: 0.31). The risk of an event decreased by 80% after CR compared to IR (hazard ratio = 0.20; p < 0.001). Irradiation had protective effects on EFS: irradiated patients had an 88% lower risk of recurrence/progression compared to patients without/before irradiation (hazard ratio = 0.12; p < 0.001). GH treatment had no impact on 3-year EFS rates. Conclusions: Tumor recurrences/progressions are frequent and occur early after initial treatment of childhood craniopharyngioma. A radical resection preserving the integrity of hypothalamic structures appears optimal at original diagnosis. Irradiation was efficient in preventing recurrences/progressions. GH treatment had no impact on the low 3-year EFS observed in our study. However, further conclusions on the influence of GH on recurrence rates have to be refined to long-term follow-up studies of patients with childhood craniopharyngioma.


Psychotherapy and Psychosomatics | 2012

Type D personality as a cardiovascular risk marker in the general population: results from the Gutenberg health study.

Manfred E. Beutel; Jörg Wiltink; Y. Till; P.S. Wild; T. Münzel; F.M. Ojeda; T. Zeller; R.B. Schnabel; K. Lackner; Maria Blettner; Isabella Zwiener; Matthias Michal

Background: Type D personality is considered as an independent risk factor for morbidity and mortality in cardiovascular patients and a vulnerability factor for distress in the general population. Because representative community studies are rare, we sought to determine the prevalence of type D personality and its relationship with demographic characteristics, different features of mental disorders, cardiovascular risk factors, health behavior, endothelial function and cardiovascular biomarkers in the general population. Methods: The prevalence of type D personality and its correlates were analyzed cross-sectionally in a population-based sample of 5,000 Mid-Europeans aged 35–74 years from the Gutenberg Health Study. Results: The prevalence of type D personality was 22.2% without remarkable differences in sex distribution. Type D subjects were characterized by lower socioeconomic status, lack of a partnership, increased depression, anxiety, depersonalization and health care utilization. Despite its strong association with mental disorders, type D personality emerged as psychometrically distinct. Although type D personality was independently associated with coronary heart disease (OR = 1.54, p = 0.044), no associations with traditional cardiovascular risk factors were found independently from depression or anxiety. Conclusions: Although type D personality is strongly associated with depression, anxiety, impaired mental and somatic health status, and increased health care utilization, the type D construct seems to comprise dysfunctional personality patterns not covered by depression and anxiety scales. Beyond these associations, the pathways of the cardiotoxic impact of type D personality remain to be elucidated. There is a need for prospective population studies on potential links between type D personality and cardiac disease.


PLOS ONE | 2014

Transforming RNA-Seq Data to Improve the Performance of Prognostic Gene Signatures

Isabella Zwiener; Barbara Frisch; Harald Binder

Gene expression measurements have successfully been used for building prognostic signatures, i.e for identifying a short list of important genes that can predict patient outcome. Mostly microarray measurements have been considered, and there is little advice available for building multivariable risk prediction models from RNA-Seq data. We specifically consider penalized regression techniques, such as the lasso and componentwise boosting, which can simultaneously consider all measurements and provide both, multivariable regression models for prediction and automated variable selection. However, they might be affected by the typical skewness, mean-variance-dependency or extreme values of RNA-Seq covariates and therefore could benefit from transformations of the latter. In an analytical part, we highlight preferential selection of covariates with large variances, which is problematic due to the mean-variance dependency of RNA-Seq data. In a simulation study, we compare different transformations of RNA-Seq data for potentially improving detection of important genes. Specifically, we consider standardization, the log transformation, a variance-stabilizing transformation, the Box-Cox transformation, and rank-based transformations. In addition, the prediction performance for real data from patients with kidney cancer and acute myeloid leukemia is considered. We show that signature size, identification performance, and prediction performance critically depend on the choice of a suitable transformation. Rank-based transformations perform well in all scenarios and can even outperform complex variance-stabilizing approaches. Generally, the results illustrate that the distribution and potential transformations of RNA-Seq data need to be considered as a critical step when building risk prediction models by penalized regression techniques.


BMC Psychiatry | 2013

Associations between depression and different measures of obesity (BMI, WC, WHtR, WHR)

Jörg Wiltink; Matthias Michal; Philipp S. Wild; Isabella Zwiener; Maria Blettner; Thomas Münzel; Andreas Schulz; Yvonne Kirschner; Manfred E. Beutel

BackgroundGrowing evidence suggests that abdominal obesity is a more important risk factor for the prognosis of cardiovascular and metabolic diseases than BMI. Somatic-affective symptoms of depression have also been linked to cardiovascular risk. The relationship between obesity and depression, however, has remained contradictory. Our aim was therefore to relate body mass index (BMI) and different measures for abdominal obesity (waist circumference, WC, waist-to-hip ratio, WHR, waist-to-height ratio, WHtR) to somatic vs. cognitive-affective symptoms of depression.MethodsIn a cross-sectional population based study, data on the first N = 5000 participants enrolled in the Gutenberg Health Study (GHS) are reported. To analyze the relationship between depression and obesity, we computed linear regression models with the anthropometric measure (BMI, WC, WHR, WHtR) as the dependent variable and life style factors, cardiovascular risk factors and psychotropic medications as potential confounders of obesity/depression.ResultsWe found that only the somatic, but not the cognitive-affective symptoms of depression are consistently positively associated with anthropometric measures of obesity.ConclusionsWe could demonstrate that the somatic-affective symptoms of depression rather than the cognitive-affective symptoms are strongly related to anthropometric measures. This is also true for younger obese starting at the age of 35 years. Our results are in line with previous studies indicating that visceral adipose tissue plays a key role in the relationship between obesity, depression and cardiovascular disease.


Journal of Hypertension | 2013

Association of hypertension with depression in the community: results from the Gutenberg Health Study.

Matthias Michal; Jörg Wiltink; Karl J. Lackner; Philipp S. Wild; Isabella Zwiener; Maria Blettner; Thomas Münzel; Andreas Schulz; Yvonne Kirschner; Manfred E. Beutel

Objective: The literature on the depression–hypertension (HTN) relationship came to conflicting results. Previous studies reported close positive as well as close negative associations between HTN and depression. Against this background, the present study sought to analyze this relationship in a large population-based study. Methods: This cross-sectional population-based study (N = 5000) analyzed the association of depression and HTN in persons with different conditions of HTN (unaware of HTN, controlled HTN, uncontrolled HTN) as compared to persons without HTN. Furthermore, the relationships of depressive symptoms with antihypertensive drugs and blood pressure were examined. Results: A total of 48.6% of participants were classified as ‘no HTN’, 13.5% had controlled HTN, 23.4% had uncontrolled HTN and 14.2% were unaware of their HTN. Unawareness of HTN was inversely associated with burden of depression. Controlled HTN was positively associated with depression. However, this association was due to generally increased disease burden (e.g. stroke, diabetes). Severity of cognitive symptoms of depression was negatively associated with SBP in persons free of antihypertensive drugs (&bgr; = −0.64, P = 0.0005). Intake of &bgr;-blockers and agents acting on the renin–angiotensin system was associated with severity of somatic symptoms of depression (e.g. fatigue). Conclusion: The competing literature about the relationships between depression and HTN may be the result of the insufficient recognition of multiple pathways of opposite directions linking depressive symptoms with blood pressure, HTN and related medications.


PLOS ONE | 2013

Differential Associations of Depressive Symptom Dimensions with Cardio-Vascular Disease in the Community: Results from the Gutenberg Health Study

Matthias Michal; Jörg Wiltink; Yvonne Kirschner; Philipp S. Wild; Thomas Münzel; Francisco Ojeda; Tanja Zeller; Renate B. Schnabel; Karl J. Lackner; Maria Blettner; Isabella Zwiener; Manfred E. Beutel

A current model suggested that the somatic symptom dimension accounts for the adverse effect of depression in patients with coronary heart disease (CHD). In order to test this model we sought to determine in a large population-based sample how symptom dimensions of depression are associated with CHD, biomarkers and traditional risk factors. The associations of cognitive and somatic symptom dimensions of depression with CHD, risk factors, endothelial function, and biomarkers of inflammation and myocardial stress were analyzed cross-sectionally in a sample of n = 5000 Mid-Europeans aged 35–74 years from the Gutenberg Health Study (GHS). Only the somatic symptom dimension of depression was associated with CHD, biomarkers (inflammation, vascular function) and cardio-vascular risk factors. When multivariable adjustment was applied by demographic and cardiovascular risk factors, the weak associations of the somatic symptom dimension with the biomarkers disappeared. However, the associations of the somatic symptom dimension with CHD, myocardial infarction, obesity, dyslipidemia and family history of myocardial infarction remained. Both dimensions of depression were independently associated with a previous diagnosis of depression and distressed personality (type D). Thus, our results partly confirm current models: Somatic, but not cognitive-affective symptom dimensions are responsible for the association between depression and CHD, inflammation, vascular function and cardiovascular risk factors in the general population. However, our findings challenge the assumptions that somatic depression might be due to inflammation or vascular dysfunction as consequence of progressed atherosclerotic disease. They rather emphasize a close interplay with life-style factors and with a family history of MI.


Acta Ophthalmologica | 2015

Ranibizumab for Branch Retinal Vein Occlusion Associated Macular Edema Study (RABAMES): six-month results of a prospective randomized clinical trial

Amelie Pielen; Alireza Mirshahi; Nicolas Feltgen; Katrin Lorenz; Christina Korb; Bernd Junker; Caroline Schaefer; Isabella Zwiener; Lars-Olof Hattenbach

To compare standard‐of‐care grid laser photocoagulation versus intravitreal ranibizumab (IVR) versus a combination of both in the treatment of chronic (>3 months) macular oedema secondary to branch retinal vein occlusion.

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