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Berlin, Germany

Werncke T.,Charite - Medical University of Berlin | Von Falck C.,Hannover Medical School | Wittmann M.,Institute For Diagnostische Und Interventionelle Radiologie | Elgeti T.,Universitaetsmedizin Berlin | And 2 more authors.
European Radiology | Year: 2013

Objectives: To assess the influence of different table feeds (TFs) on vascular enhancement and image quality in patients with an abdominal aortic aneurysm (AAA) undergoing computed tomography (CT) angiography of the lower extremities (run-off CTA). Methods: Seventy-nine patients (71 ± 8 years) with an AAA (>30 mm) who underwent run-off CTA between January 2004 and August 2011 were included in this retrospective institutional review board-approved study. Run-off CTA was conducted using 16- and 64-row CT. The range of TFs was 30-86 mm/s and was categorised in quartiles TF1 (32.6 ± 1.9 mm/s), TF2 (38.9 ± 0.9 mm/s), TF3 (43.9 ± 3.1 mm/s) and TF4 (57.4 ± 10.5 mm/s). Image quality was rated independently by two radiologists and vessel enhancement was assessed. Results: Image quality was diagnostic at all aortic, pelvic and almost all thigh levels. Below the knee, the number of diagnostic levels was highest for TF1 and decreased to TF4. Arterial enhancement between the aorta and fibular trunk was not different in all TF groups, P > 0.05. At the calf and foot strongest arterial enhancement was noted for TF1 and TF2 and decreased to TF4, P < 0.01. Conclusion: Results indicate that the highest image quality of run-off CTA in patients with an AAA may be obtained using table feeds measuring 30-35 mm/s. Key Points: • CTA has become a key investigation for peripheral vascular disease. • Run-off CTA is more complex in patients with an abdominal aortic aneurysm. • Run-off CTA is feasible with a short bolus of intravenous contrast medium. • A constant 30-35 mm/s table feed provides the highest likelihood of diagnostic images. © 2013 European Society of Radiology. Source


Mochales C.,University of Barcelona | Mochales C.,Universitaetsmedizin Berlin | Wilson R.M.,University of London | Dowker S.E.P.,Queen Mary, University of London | Ginebra M.-P.,University of Barcelona
Journal of Alloys and Compounds | Year: 2011

Dry mechanosynthesis is an efficient technique to synthesise nanocrystalline calcium deficient hydroxyapatites (CDHA). The mechanisms underlying a mechanochemical reaction are different from those triggering a dissolution mediated process, and this can have an effect on the structural features of the product. In this work, a nanocrystalline CDHA with Ca/P molar ratio of 1.5 obtained by means of dry mechanosynthesis of calcium oxide and dicalcium phosphate dihydrate was analysed. Spectroscopic techniques confirmed the presence of hydrogen phosphate (HPO 4 2-) groups and a non-apatitic environment of the phosphate ions and disordered hydroxyl groups due to the nanometric size of the crystals. Lattice parameters of mechanosynthesised CDHA showed a small increase in the a lattice parameter (9.4418(20) ) and a small decrease in the c lattice parameter (6.8745(17) ), in agreement with the values reported in the literature for precipitated CDHAs. A prolonged milling resulted in an increase of the crystallinity of the CDHA and its partial decomposition into β-TCP by the loss of OH - and HPO 4 2- groups. © 2011 Elsevier B.V. All rights reserved. Source


Burghardt A.J.,University of California at San Francisco | Issever A.S.,University of California at San Francisco | Issever A.S.,Universitaetsmedizin Berlin | Schwartz A.V.,University of California at San Francisco | And 5 more authors.
Journal of Clinical Endocrinology and Metabolism | Year: 2010

Context: Cross-sectional epidemiological studies have found that patients with type 2 diabetes mellitus (T2DM) have a higher incidence of certain fragility fractures despite normal or elevated bone mineral density (BMD). Objective: In this study, high-resolution peripheral quantitative computed tomography was applied to characterize cortical and trabecular microarchitecture and biomechanics in the peripheral skeleton of female patients with T2DM. Design and Setting: A cross-sectional study was conducted in patients with T2DM recruited from a diabetic outpatient clinic. Participants: Elderly female patients (age, 62.9 ± 7.7 yr) with a history of T2DM (n = 19) and age-and height-matched controls (n = 19) were recruited. Outcome Measures: Subjects were imaged using high-resolution peripheral quantitative computed tomography at the distal radius and tibia. Quantitative measures of volumetric (BMD), cross-sectional geometry, trabecular and cortical microarchitecture were calculated. Additionally, compressive mechanical properties were determined by micro-finite element analysis. Results: Compared to the controls, the T2DM cohort had 10% higher trabecular volumetric BMD (P < 0.05) adjacent to the cortex and higher trabecular thickness in the tibia (13.8%; P < 0.05). Cortical porosity differences alone were consistent with impaired bone strength and were significant in the radius (>+50%;P < 0.05), whereas pore volume approached significance in the tibia (+118%;P = 0.1). Conclusion: The results of this pilot investigation provide a potential explanation for the inability of standard BMD measures to explain the elevated fracture incidence in patients with T2DM. The findings suggest that T2DM may be associated with impaired resistance to bending loads due to inefficient redistribution of bone mass, characterized by loss of intracortical bone offset by an elevation in trabecular bone density. Copyright © 2010 by The Endocrine Society. Source


Didier A.,Rangueil Larrey Hospital | Worm M.,Universitaetsmedizin Berlin | Horak F.,Allergy Center Vienna West | Sussman G.,University of Toronto | And 4 more authors.
Journal of Allergy and Clinical Immunology | Year: 2011

Background: Seasonal allergic rhinoconjunctivitis affects millions of persons. The efficacy of allergen sublingual immunotherapy (SLIT) was demonstrated in previous short-term studies. Objectives: We sought to evaluate the sustained efficacy of 2 dosing regimens of a pre- and coseasonal treatment with 300 IR (index of reactivity) 5-grass-pollen SLIT tablets (Oralair) compared with placebo assessed by using the average adjusted symptom score (AAdSS) at season 3 in adults with grass pollen-induced rhinoconjunctivitis. Methods: Six hundred thirty-three patients were treated for either 2 or 4 months before and then during the grass pollen season with active or placebo treatment for 3 consecutive seasons. The primary outcome was the AAdSS, a symptom score adjusted for rescue medication use, after 3 consecutive treatment seasons. Secondary outcomes were symptoms and rescue medication score, quality-of-life, and safety assessments. Results: The mean AAdSS was reduced by 36.0% and 34.5% at season 3 in the 2- and 4-month pre- and coseasonal active treatment groups, respectively, compared with that in the placebo group (P <.0001 for both). Reductions were observed in total symptom scores and ISSs and the medication score, with a marked improvement in quality of life for both active groups compared with the placebo group at season 3. Most treatment-emergent adverse events were local reactions expected with SLIT, decreasing in number and intensity in each treatment season. Conclusions: Sustained efficacy of 2- and 4-month pre- and coseasonal treatment with the 300 IR tablet over 3 pollen seasons was demonstrated, with reduction in symptoms and rescue medication use. The treatment was well tolerated. Adverse events decreased in number and intensity over the 3 seasons. © 2011 American Academy of Allergy, Asthma & Immunology. Source


Wiedemann A.U.,Free University of Berlin | Gardner B.,University College London | Knoll N.,Free University of Berlin | Burkert S.,Universitaetsmedizin Berlin
Applied Psychology: Health and Well-Being | Year: 2014

Background: Habit formation is thought to lead to long-term maintenance of fruit and vegetable consumption. Habits develop through context-dependent repetition, but additional variables such as intrinsic reward of behaviour may influence habit strength. Drawing upon the Associative-Cybernetic Model, this exploratory study tested different pathways by which intrinsic reward may influence fruit and vegetable consumption habit strength. Methods: In a three-wave study of fruit and vegetable intake in adults (N=127) from the general population, intrinsic reward, intention, and self-efficacy were assessed at baseline, fruit and vegetable consumption and intrinsic reward two weeks later, and habit strength another two weeks later. Direct, indirect, and moderation effects of intrinsic reward on habit strength were tested simultaneously in a moderated mediation model. Results: Intrinsic reward had a positive indirect effect on habit strength through its influence on the frequency of fruit and vegetable consumption. Further, the relationship between fruit and vegetable consumption and habit was stronger where consumption was considered more intrinsically rewarding. Conclusions: Findings highlight the potential relevance of intrinsic reward to habit. We suggest that intrinsic rewards from behaviour may not only facilitate habit via behaviour frequency, but also reinforce the relationship between behavioural repetition and habit strength. © 2013 The International Association of Applied Psychology. Source

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