TY - JOUR A1 - Temiz Artmann, Aysegül A1 - Saklamaz, Ali A1 - Comlekci, Abdurrahman A1 - Caliskan, Sezer T1 - The beneficial effects of lipid-lowering drugs beyond lipid-lowering effects: A comparative study with pravastatin, atorvastatin, and fenofibrate in patients with type IIa and type IIb hyperlipidemia / Saklamaz, Ali ; Comlekci, Abdurrahman ; Temiz, Aysegu JF - Metabolism. 54 (2005), H. 5 Y1 - 2005 SN - 0026-0495 SP - 677 EP - 681 ER - TY - BOOK A1 - Digel, Ilya A1 - Zhubanova, Azhar Ahmetovna A1 - Akimbekov, Nuraly S. T1 - Visual Virology Y1 - 2012 SN - 978-601-247-298-1 N1 - Text kasachisch, russisch, englisch CY - Almaty ER - TY - JOUR A1 - Staat, Manfred A1 - Vu, Duc Khoi T1 - Limit analysis of flaws in pressurized pipes and cylindrical vessels Part II: Circumferential defects JF - Engineering Fracture Mechanics ; 97(2013), H. 1 N2 - Upper and lower bound theorems of limit analyses have been presented in part I of the paper. Part II starts with the finite element discretization of these theorems and demonstrates how both can be combined in a primal–dual optimization problem. This recently proposed numerical method is used to guide the development of a new class of closed-form limit loads for circumferential defects, which show that only large defects contribute to plastic collapse with a rapid loss of strength with increasing crack sizes. The formulae are compared with primal–dual FEM limit analyses and with burst tests. Even closer predictions are obtained with iterative limit load solutions for the von Mises yield function and for the Tresca yield function. Pressure loading of the faces of interior cracks in thick pipes reduces the collapse load of circumferential defects more than for axial flaws. Axial defects have been treated in part I of the paper. Y1 - 2012 U6 - https://doi.org/10.1016/j.engfracmech.2012.05.017 SN - 0013-7944 VL - 97 SP - 314 EP - 333 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Doorschodt, B. M. A1 - Schreinemachers, M. C. J. M. A1 - Behbahani, Mehdi A1 - Florquin, S. A1 - Weis, J. A1 - Staat, Manfred A1 - Tolba, R. H. T1 - Hypothermic machine perfusion of kidney grafts: which pressure is preferred JF - Annals of Biomedical Engineering. 39 (2011), H. 3 Y1 - 2011 SN - 1573-9686 SP - 1051 EP - 1059 PB - Springer CY - Berlin ER - TY - JOUR A1 - Amin, Rashid A1 - Temiz Artmann, Aysegül A1 - Artmann, Gerhard A1 - Lazarovici, Philip A1 - Lelkes, Peter I. T1 - Permeability of an In Vitro Model of Blood Brain Barrier (BBB) JF - 13th International Conference on Biomedical Engineering / Lim, Chwee Teck [Ed.] Y1 - 2009 SN - 978-3-540-92841-6 N1 - IFMBE Proceedings ; 23, Track 1 ; ICBME 2008 3–6 December 2008 Singapore SP - 81 EP - 84 ER - TY - JOUR A1 - Behbahani, Mehdi A1 - Tran, L. A1 - Jockenhövel, S. A1 - Behr, M. A1 - Mottaghy, K. T1 - Numerical prediction of thrombocyte reactions for application to a vascular flow model JF - British Journal of Surgery Y1 - 2011 SN - 1365-2168 N1 - 46th Congress of the European Society for Surgical Research, Aachen, Germany, 25-28 May 2011 ; ESSR Abstracts 2011 ; Oral Sessions OP10-5 VL - 98 IS - S5 SP - S17 PB - Oxford University Press CY - Oxford ER - TY - JOUR A1 - Behbahani, Mehdi A1 - Tran, L. A1 - Waluga, C. A1 - Behr, M. A1 - Oedekoven, B. A1 - Mottaghy, K. T1 - Model-based Numerical Analysis of Platelet Adhesion, Thrombus Growth and Aggregation for Assist Devices JF - The International Journal of Artificial Organs. 32 (2009), H. 7 Y1 - 2009 SN - 0391-3988 N1 - Abstracts - Oral Presentations: XXXVI Annual ESAO Congress, 2-5 September 2009, Compiègne - France; European Society of Artificial Organs (ESAO), Compiegne, France, September 2-5, 2009 SP - 398 EP - 398 ER - TY - JOUR A1 - Leimena, W. A1 - Artmann, Gerhard A1 - Dachwald, Bernd A1 - Temiz Artmann, Aysegül A1 - Gossmann, Matthias A1 - Digel, Ilya T1 - Feasibility of an in-situ microbial decontamination of an ice-melting probe JF - Eurasian Chemico-Technological Journal. 12 (2010), H. 2 Y1 - 2010 SN - 1562-3920 SP - 145 EP - 150 ER - TY - JOUR A1 - Behbahani, Mehdi A1 - Nam, J. A1 - Waluga, C. A1 - Behr, M. A1 - Pasquali, M. A1 - Mottaghy, K. T1 - Modeling and Numerical Analysis of Platelet Activation, Adhesion and Aggregation in Artificial Organs Y1 - 2010 U6 - https://doi.org/10.1097/01.mat.0000369377.65122.a3 N1 - Posterpresentation American Society of Artificial Organs (ASAIO), Baltimore, USA, May 27-29, 2010 ER - TY - JOUR A1 - Jansen, S. V. A1 - Behbahani, Mehdi A1 - Laumen, M. A1 - Kaufmann, T. A1 - Hormes, M. A1 - Behr, M. A1 - Schmitz-Rode, T. A1 - Steinseifer, U. T1 - Investigation of Steady Flow Through a Realistic Model of the Thoracic Human Aorta Using 3D Stereo PIV and CFD-Simulation Y1 - 2010 N1 - Posterpresentation ; American Society of Artificial Organs (ASAIO), Baltimore, USA, May 27-29, 2010 ER - TY - JOUR A1 - Nam, J. A1 - Arora, D. A1 - Behbahani, Mehdi A1 - Probst, M. A1 - Benkowski, R. A1 - Behr, M. A1 - Pasquali, M. T1 - New computational method in hemolysis analysis for artificial heart pump Y1 - 2010 N1 - Posterpresentation ; American Society of Artificial Organs (ASAIO), Baltimore, USA, May 27-29, 2010 ER - TY - JOUR A1 - Behbahani, Mehdi A1 - Probst, M. A1 - Mai, A. A1 - Behr, M. A1 - Tran, L. A1 - Vonderstein, K. A1 - Mottaghy, K. T1 - Numerical Prediction of Blood Damage in Biomedical Devices Y1 - 2010 N1 - Posterpresentation ; Biomedica Congress, Aachen, March 17-18, 2010 ER - TY - JOUR A1 - Probst, M. A1 - Behbahani, Mehdi A1 - Borrmann, E. A1 - Elgeti, S. A1 - Nicolai, M. A1 - Behr, M. T1 - Hemodynamic Modeling for Numerical Analysis and Design of Medical Devices Y1 - 2010 N1 - Posterpresentation ; NIC Symposium 2010 ; 24 - 25 February 2010 Jülich, Germany ER - TY - JOUR A1 - Behbahani, Mehdi A1 - Waluga, C. A1 - Stock, S. A1 - Mai, A. A1 - Bergmann, B. A1 - Behr, M. A1 - Tran, L. A1 - Vonderstein, K. A1 - Scheidt, H. A1 - Oedekoven, B. A1 - Mottaghy, K. T1 - Modelling and Numerical Analysis of Platelet Reactions and Surface Thrombus Growth Y1 - 2009 N1 - Posterpresentation ; European Society of Biomaterials (ESB), Lausanne, Switzerland, September 7-10, 2009 ER - TY - JOUR A1 - Behbahani, Mehdi A1 - Mai, A. A1 - Bergmann, B. A1 - Waluga, C. A1 - Behr, M. A1 - Tran, L. A1 - Vonderstein, K. A1 - Mottaghy, K. T1 - Modeling and Numerical Simulation of Blood Damage Y1 - 2010 N1 - Posterpresentation ; Umbrella Symposium "Modelling and Simulation in Medicine, Engineering and Sciences", Forschungszentrum Jülich, January 18-20, 2010 ER - TY - JOUR A1 - Behbahani, Mehdi A1 - Waluga, C. A1 - Arlt, S. A1 - Behr, M. A1 - Mottaghy, K. T1 - Computational Analysis of Platelet Aggregation in a Taylor-Couette System JF - The International Journal of Artificial Organs. 31 (2008), H. 7 Y1 - 2008 SN - 0391-3988 N1 - Posterpresentation ; European Society of Artificial Organs (ESAO), Geneva, Switzerland SP - 643 ER - TY - JOUR A1 - Behbahani, Mehdi A1 - Mai, A. A1 - Waluga, C. A1 - Bergmann, B. A1 - Tran, L. A1 - Vonderstein, K. A1 - Behr, M. A1 - Mottaghy, K. T1 - Numerical Modeling of Flow-Related Thrombus Formation under Physiological and Non-Physiological Flow Conditions JF - Acta Physiologica Y1 - 2010 SN - 1748-1716 N1 - Joint Congress of the Scandinavian and German Physiological Societies, Copenhagen, Denmark, March 27-30, 2010 VL - 198 IS - Supplement 677 SP - 185 ER - TY - JOUR A1 - Kurulgan Demirci, Eylem A1 - Demirci, Taylan A1 - Linder, Peter A1 - Trzewik, Jürgen A1 - Gierkowski, Jessica Ricarda A1 - Gossmann, Matthias A1 - Kayser, Peter A1 - Porst, Dariusz A1 - Digel, Ilya A1 - Artmann, Gerhard A1 - Temiz Artmann, Aysegül T1 - rhAPC reduces the endothelial cell permeability via a decrease of contractile tensions induced by endothelial cells JF - Journal of Bioscience and Bioengineering N2 - All cells generate contractile tension. This strain is crucial for mechanically controlling the cell shape, function and survival. In this study, the CellDrum technology quantifying cell's (the cellular) mechanical tension on a pico-scale was used to investigate the effect of lipopolysaccharide (LPS) on human aortic endothelial cell (HAoEC) tension. The LPS effect during gram-negative sepsis on endothelial cells is cell contraction causing endothelium permeability increase. The aim was to finding out whether recombinant activated protein C (rhAPC) would reverse the endothelial cell response in an in-vitro sepsis model. In this study, the established in-vitro sepsis model was confirmed by interleukin 6 (IL-6) levels at the proteomic and genomic levels by ELISA, real time-PCR and reactive oxygen species (ROS) activation by florescence staining. The thrombin cellular contraction effect on endothelial cells was used as a positive control when the CellDrum technology was applied. Additionally, the Ras homolog gene family, member A (RhoA) mRNA expression level was checked by real time-PCR to support contractile tension results. According to contractile tension results, the mechanical predominance of actin stress fibers was a reason of the increased endothelial contractile tension leading to enhanced endothelium contractility and thus permeability enhancement. The originality of this data supports firstly the basic measurement principles of the CellDrum technology and secondly that rhAPC has a beneficial effect on sepsis influenced cellular tension. The technology presented here is promising for future high-throughput cellular tension analysis that will help identify pathological contractile tension responses of cells and prove further cell in-vitro models. KW - Cell permeability KW - Cellular force KW - Endothelial cells KW - Recombinant activated protein C KW - Lipopolysaccharide KW - Contractile tension KW - CellDrum Y1 - 2012 U6 - https://doi.org/10.1016/j.jbiosc.2012.03.019 SN - 1347-4421 VL - 113 IS - 2 SP - 212 EP - 219 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Novacek, V. A1 - Tran, Thanh Ngoc A1 - Klinge, U. A1 - Tolba, R. H. A1 - Staat, Manfred A1 - Bronson, D. G. A1 - Miesse, A. M. A1 - Whiffen, J. A1 - Turquier, F. T1 - Finite element modelling of stapled colorectal end-to-end anastomosis : Advantages of variable height stapler design JF - Journal of Biomechanics N2 - The impact of surgical staplers on tissues has been studied mostly in an empirical manner. In this paper, finite element method was used to clarify the mechanics of tissue stapling and associated phenomena. Various stapling modalities and several designs of circular staplers were investigated to evaluate the impact of the device on tissues and mechanical performance of the end-to-end colorectal anastomosis. Numerical simulations demonstrated that a single row of staples is not adequate to resist leakage due to non-linear buckling and opening of the tissue layers between two adjacent staples. Compared to the single staple row configuration, significant increase in stress experienced by the tissue at the inner staple rows was observed in two and three rows designs. On the other hand, adding second and/or third staple row had no effect on strain in the tissue inside the staples. Variable height design with higher staples in outer rows significantly reduced the stresses and strains in outer rows when compared to the same configuration with flat cartridge. KW - Variable height stapler design KW - Anastomotic leakage KW - Finite element modelling KW - End-to-end colorectal anastomosis KW - Surgical staplers Y1 - 2012 U6 - https://doi.org/10.1016/j.jbiomech.2012.07.021 SN - 1873-2380 VL - 45 IS - 115 SP - 2693 EP - 2697 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Nguyen, Nhu Huynh A1 - Duong, Minh Tuan A1 - Tran, Thanh Ngoc A1 - Pham, Phu Tinh A1 - Grottke, O. A1 - Tolba, R. A1 - Staat, Manfred T1 - Influence of a freeze–thaw cycle on the stress–stretch curves of tissues of porcine abdominal organs JF - Journal of Biomechanics N2 - The paper investigates both fresh porcine spleen and liver and the possible decomposition of these organs under a freeze–thaw cycle. The effect of tissue preservation condition is an important factor which should be taken into account for protracted biomechanical tests. In this work, tension tests were conducted for a large number of tissue specimens from twenty pigs divided into two groups of 10. Concretely, the first group was tested in fresh state; the other one was tested after a freeze-thaw cycle which simulates the conservation conditions before biomechanical experiments. A modified Fung model for isotropic behavior was adopted for the curve fitting of each kind of tissues. Experimental results show strong effects of the realistic freeze–thaw cycle on the capsule of elastin-rich spleen but negligible effects on the liver which virtually contains no elastin. This different behavior could be explained by the autolysis of elastin by elastolytic enzymes during the warmer period after thawing. Realistic biomechanical properties of elastin-rich organs can only be expected if really fresh tissue is tested. The observations are supported by tests of intestines. KW - Autolysis KW - Decomposition KW - Freeze–thaw process KW - Spleen KW - Liver Y1 - 2012 U6 - https://doi.org/10.1016/j.jbiomech.2012.07.008 SN - 1873-2380 VL - 45 IS - 14 SP - 2382 EP - 2386 PB - Elsevier CY - Amsterdam ER -