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Burg bei Magdeburg, Germany

Goette A.,St. Vincenz Hospital Paderborn | Bukowska A.,University Hospital Magdeburg | Lillig C.H.,University of Greifswald | Lendeckel U.,University of Greifswald
Frontiers in Physiology | Year: 2012

Patients with atrial fibrillation (AF) often present with typical angina pectoris and mildly elevated levels of cardiac troponin (non-ST-segment elevation myocardial infarction) during an acute episode of AF. However, in a large proportion of these patients, significant coronary artery disease is excluded by coronary angiography, which suggests that AF itself influences myocardial blood flow.The present review summarizes the effect of AF on the occurrence of ventricular oxidative stress, redox-sensitive signaling pathways and gene expression, and microcirculatory flow abnormalities in the left ventricle. © 2012 Goette, Bukowska, Lillig and Lendeckel. Source

Hughes O.R.,Royal National Throat | Stone N.,Biophotonics Research Unit | Kraft M.,Kantonsspital Aarau | Arens C.,University Hospital Magdeburg | Birchall M.A.,Royal National Throat
Head and Neck | Year: 2010

Failure to remove tumor cells from the larynx significantly increases the risk of local recurrence following surgical excision. Healthy tissue must be preserved to optimize long-term vocal and swallowing function. It is essential to accurately distinguish between healthy mucosa, dysplasia, and invasive carcinoma. Optical and molecular examining technologies have been developed to improve tumor margin identification in vivo. We aimed to review the efficacy of these technologies. Published articles were identified using MEDLINE, EMBASE, and Cochrane central register of controlled trials (CENTRAL). Randomized clinical trials are required to establish the benefit to patients and cost to the health service of using 5-aminolevulinic acid (ALA)-induced fluorescent imaging, contact endoscopy, and optical coherence tomography (OCT). Furthermore, primary research is required to validate other techniques, such as confocal endomicroscopy and Raman spectroscopy, and to develop their clinical applications in the larynx. © 2010 Wiley Periodicals, Inc. Source

Gasteiger R.,Otto Von Guericke University of Magdeburg | Neugebauer M.,Otto Von Guericke University of Magdeburg | Beuing O.,University Hospital Magdeburg | Preim B.,Otto Von Guericke University of Magdeburg
IEEE Transactions on Visualization and Computer Graphics | Year: 2011

Blood flow and derived data are essential to investigate the initiation and progression of cerebral aneurysms as well as their risk of rupture. An effective visual exploration of several hemodynamic attributes like the wall shear stress (WSS) and the inflow jet is necessary to understand the hemodynamics. Moreover, the correlation between focus-and-context attributes is of particular interest. An expressive visualization of these attributes and anatomic information requires appropriate visualization techniques to minimize visual clutter and occlusions. We present the FLOWLENS as a focus-and-context approach that addresses these requirements. We group relevant hemodynamic attributes to pairs of focus-and-context attributes and assign them to different anatomic scopes. For each scope, we propose several FLOWLENS visualization templates to provide a flexible visual filtering of the involved hemodynamic pairs. A template consists of the visualization of the focus attribute and the additional depiction of the context attribute inside the lens. Furthermore, the FLOWLENS supports local probing and the exploration of attribute changes over time. The FLOWLENS minimizes visual cluttering, occlusions, and provides a flexible exploration of a region of interest. We have applied our approach to seven representative datasets, including steady and unsteady flow data from CFD simulations and 4D PC-MRI measurements. Informal user interviews with three domain experts confirm the usefulness of our approach. © 2011 IEEE. Source

Holzel M.,University of Bonn | Tuting T.,University Hospital Magdeburg
Trends in Immunology | Year: 2016

Phenotype switching contributes to nongenomic heterogeneity in melanoma and other cancers. These dynamic and in part reversible phenotype changes impose diagnostic and therapeutic challenges. Understanding the reciprocal coevolution of melanoma and immune cell phenotypes during disease progression and in response to therapy is a prerequisite to improve current treatment strategies. Here we discuss how proinflammatory signals promote melanoma cell plasticity and govern interactions of melanoma and immune cells in the tumor microenvironment. We examine phenotypic plasticity and heterogeneity in different melanoma mouse models with respect to their utility for translational research and emphasize the interplay between melanoma cells and neutrophils as a critical driver of metastasis. © 2016 Elsevier Ltd. Source

Scheufler K.-M.,Innsbruck Medical University | Franke J.,University Hospital Magdeburg | Dohmen H.,University of Zurich
Neurosurgery | Year: 2011

BACKGROUND: Image-guided spinal instrumentation may reduce complications in spinal instrumentation. OBJECTIVE: To assess accuracy, time efficiency, and staff radiation exposure during thoracolumbar screw instrumentation guided by intraoperative computed tomography (iCT)-based neuronavigation (iCT-N). METHODS: In 55 patients treated for idiopathic and degenerative deformities, 826 screws were inserted in the thoracic (T2-T12; n = 243) and lumbosacral (L1-S1; n = 545) spine, as well as ilium (n = 38) guided by iCT-N. Up to 17 segments were instrumented following a single automated registration sequence with the dynamic reference arc (DRA) uniformly attached to L5. Accuracy of iCT-N was assessed by calculating angular deviations between individual navigated tool trajectories and final implant positions. Final screw positions were also graded according to established classification systems. Clinical and radiological outcome was assessed at 12 to 14 months. RESULTS: Additional intraoperative fluoroscopy was unnecessary, eliminating staff radiation exposure. Unisegmental K-wire insertion required 4.6 ± 2.9 minutes. Of the thoracic pedicle screws 98.4% were assigned grades I to III according to the Heary classification, with 1.6% grade IV placement. In the lumbar spine, 94.4% of screws were completely contained (Gertzbein classification grade 0), 4.6% displayed minor pedicle breaches <2 mm (grade 1), and 1% of lumbar screws deviated by >2 to <4 mm (grade 2). The accuracy of iCT-N progressively deteriorates with increasing distance from the DRA, but allows safe instrumentation of up to 12 segments. CONCLUSION: iCT-N using automated referencing allows for safe, highly accurate multilevel instrumentation of the entire thoracolumbosacral spine and ilium, rendering additional intraoperative imaging dispensable. In addition, automated registration is time-efficient and significantly reduces the need for re-registration in multilevel surgery. Copyright © 2011 by the Congress of Neurological Surgeons. Source

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