Rades D.,University of Lubeck |
Rades D.,University of Hamburg |
Dziggel L.,University of Lubeck |
Nagy V.,Oncology and Radiotherapy Institute |
And 5 more authors.
Radiotherapy and Oncology | Year: 2013
Background and purpose Survival scores for patients with brain metastasis exist. However, the treatment regimens used to create these scores were heterogeneous. This study aimed to develop and validate a survival score in homogeneously treated patients. Materials and methods Eight-hundred-and-eighty- two patients receiving 10 × 3 Gy of WBRT alone were randomly assigned to a test group (N = 441) or a validation group (N = 441). In the multivariate analysis of the test group, age, performance status, extracranial metastasis, and systemic treatment prior to WBRT were independent predictors of survival. The score for each factor was determined by dividing the 6-month survival rate (in %) by 10. Scores were summed and total scores ranged from 6 to 19 points. Patients were divided into four prognostic groups. Results The 6-month survival rates were 4% for 6-9 points, 29% for 10-14 points, 62% for 15-17 points, and 93% for 17-18 points (p < 0.001) in the test group. The survival rates were 3%, 28%, 54% and 96%, respectively (p < 0.001) in the validation group. Conclusions Since the 6-month survival rates in the validation group were very similar to the test group, this new score (WBRT-30) appears valid and reproducible. It can help making treatment choices and stratifying patients in future trials. © 2013 Elsevier Ireland Ltd. All rights reserved. Source
Brocke J.V.,University of Liechtenstein |
Becker J.,University of Liechtenstein |
Braccini A.M.,LUISS University |
Butleris R.,Kaunas University of Technology |
And 13 more authors.
Communications of the Association for Information Systems | Year: 2011
Business process management (BPM) is a still-emerging field in the academic discipline of Information Systems (IS). This article reflects on a workshop on current and future issues in BPM research that was conducted by seventeen IS researchers from eight European countries as part of the 2010 annual meeting of the European Research Center for Information Systems (ERCIS). The results of this workshop suggest that BPM research can meaningfully contribute to investigating a broad variety of phenomena that are of interest to IS scholars, ranging from rather technical (e.g., the implementation of software architectures) to managerial (e.g., the impact of organizational culture on process performance). It further becomes noticeable that BPM researchers can make use of several research strategies, including qualitative, quantitative, and design-oriented approaches. The article offers the participants' outlook on the future of BPM research and combines their opinions with research results from the academic literature on BPM, with the goal of contributing to establishing BPM as a distinct field of research in the IS discipline. © 2011 by the Association for Information Systems. Source
The stability, selectivity and activity of nanocatalysts depend on the electronic interactions between the metal particles and their oxide support. Understanding the nature of the electron transfer across the metal/surface interface is key to improving such catalysts. A European team has now used synchrotron radiation photoelectron spectroscopy, scanning tunneling microscopy and density functional theory to determine the charge transfer per platinum atom and how this is greatest for particles containing approximately fifty platinum atoms. Noble metal nanoparticle catalysts on oxides are a class of the most common catalytic materials used across the chemical industry, in fuel production, as environmental catalysts, photocatalysts and electrocatalysts. Efficient use of the expensive and rare metal elements they contain is a priority, so chemists and materials scientists are constantly on the lookout for new ways to improve efficacy and efficiency. The details are controversial and have been for thirty years. What is known with certainty is that electronic structure, nanoscopic structure, structural flexibility and interaction with the support are the major factors in determining how well such catalysts function. Writing in the journal Nature Materials, the team also showed that one electron is transferred for every ten platinum atoms from the nanoparticle to the support. By contrast, for larger particles, the charge transfer limit is established by the support whereas nucleation effects partially inhibit charge transfer in smaller particles. "These mechanistic and quantitative insights into charge transfer will help to make better use of particle size effects and electronic metal–support interactions in metal/oxide nanomaterials," the team reports. The team comprises scientists from SISSA and CNR-IOM of Trieste, the University of Barcelona, Spain, ELETTRA Sincrotrone Trieste, Italy, Friedrich Alexander Universität Erlangen-Nürnberg, Germany and Univerzita Karlova of Prague, Czech Republic. "By combining experimental measurements and theoretical numerical simulations, we established guidelines for controlling the charge of nanoparticles and obtaining catalysts having maximum efficiency," explains team member Stefano Fabris of the CNR-IOM/SISSA. "The experimental measurements were carried out by researchers from the University of Prague at ELETTRA Sincrotrone Trieste, whereas the simulations were the result of my collaboration with the University of Barcelona." If industrial production of methanol as feedstock for fuel cells can be scaled up sustainably, perhaps by using a light-driven system that in some ways mimics photosynthesis, then the catalysts studied by the European team could be critical in releasing the pent up energy from that methanol as electricity generated in a fuel cell. David Bradley blogs at Sciencebase Science Blog and tweets @sciencebase, he is author of the bestselling science book "Deceived Wisdom".
Rades D.,University of Lubeck |
Dziggel L.,University of Lubeck |
Haatanen T.,University of Hamburg |
Veninga T.,Dr Bernard Verbeeten Institute |
And 2 more authors.
International Journal of Radiation Oncology Biology Physics | Year: 2011
Purpose: To create and validate scoring systems for intracerebral control (IC) and overall survival (OS) of patients irradiated for brain metastases. Methods and Materials: In this study, 1,797 patients were randomly assigned to the test (n = 1,198) or the validation group (n = 599). Two scoring systems were developed, one for IC and another for OS. The scores included prognostic factors found significant on multivariate analyses. Age, performance status, extracerebral metastases, interval tumor diagnosis to RT, and number of brain metastases were associated with OS. Tumor type, performance status, interval, and number of brain metastases were associated with IC. The score for each factor was determined by dividing the 6-month IC or OS rate (given in percent) by 10. The total score represented the sum of the scores for each factor. The score groups of the test group were compared with the corresponding score groups of the validation group. Results: In the test group, 6-month IC rates were 17% for 14-18 points, 49% for 19-23 points, and 77% for 24-27 points (p < 0.0001). IC rates in the validation group were 19%, 52%, and 77%, respectively (p < 0.0001). In the test group, 6-month OS rates were 9% for 15-19 points, 41% for 20-25 points, and 78% for 26-30 points (p < 0.0001). OS rates in the validation group were 7%, 39%, and 79%, respectively (p < 0.0001). Conclusions: Patients irradiated for brain metastases can be given scores to estimate OS and IC. IC and OS rates of the validation group were similar to the test group demonstrating the validity and reproducibility of both scores. © 2011 Elsevier Inc. Source
Serebruany V.L.,Osler Medical Center |
Tomek A.,University of Prague |
Pokov A.N.,Osler Medical Center |
Kim M.H.,Dong - A University
Expert Review of Cardiovascular Therapy | Year: 2015
The optimal utilization of antiplatelet therapy in patients with renal impairment (RI) following acute coronary syndromes (ACS) represents an urgent, unmet and yet unsolved need with regards to the choice of agents, duration of treatment and potential dose/regimen adjustment. The lack of any large randomized trials designed and powered specifically in such high-risk patients, absence of the uniformed efficacy and safety data reporting policy to the FDA and endless overoptimistic publications based on post hoc analyses of primary trials sometimes exaggerating benefits and hiding risks, clouds reality. In addition, triaging RI patients is problematic due to ongoing kidney deterioration and the fact that such patients are prone to both vascular occlusions and bleeding. The authors summarize available FDA-confirmed evidence from the latest trials with approved antiplatelet agents, namely clopidogrel (CAPRIE, CURE, CREDO, CLARITY, CHARISMA); prasugrel (TRITON, TRILOGY); ticagrelor (PLATO, and PEGASUS); and vorapaxar (TRACER and TRA2P) in RI patient cohorts on top of aspirin as part of dual antiplatelet therapy (DAPT). We deliberately avoided any results unless they were verified by the FDA, with the exception of the recent PEGASUS, since Agency reviews are not yet available. Despite differences among the trials and DAPT choices, RI patients universally experience much higher (HR = 1.3-3.1) rates of primary endpoint events, and bleeding risks (HR = 1.7-3.6). However, only ticagrelor increases creatinine and uric acid levels above that of clopidogrel; has the worst incidence of serious adverse events, more adverse events, and inferior outcomes in patients with severe (eGFR <30 ml/min), especially in the lowest (eGFR <15 ml/min) RI subsets. Clopidogrel, prasugrel and vorapaxar appear safer. Moreover, less aggressive half dose (5 mg/daily) prasugrel and strict DAPT, are well justified in RI, but not predominantly triple strategies with vorapaxar as tested in TRA2P and especially in TRACER. In conclusion, data from clinical trials, their sub-studies and affiliated FDA reviews indicate that RI cause more vascular occlusions and bleeding in ACS patients treated with DAPT. Among the novel antiplatelet agents, prasugrel and vorapaxar, but probably not ticagrelor, offer advantage in RI patients. © 2015 Taylor & Francis. Source