TY - JOUR A1 - Stadler, Alexander Maximilian A1 - Garvey, Christopher J. A1 - Embs, Jan Peter A1 - Koza, Michael Marek A1 - Unruh, Tobias A1 - Artmann, Gerhard A1 - Zaccai, Guiseppe T1 - Picosecond dynamics in haemoglobin from different species: A quasielastic neutron scattering study JF - Biochimica et biophysica acta (BBA): General Subjects Y1 - 2014 U6 - http://dx.doi.org/10.1016/j.bbagen.2014.06.007 SN - 1872-8006 (E-Journal); 0304-4165 (Print) VL - 1840 IS - 10 SP - 2989 EP - 2999 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Stadler, Andreas M. A1 - Digel, Ilya A1 - Embs, Jan P. A1 - Unruh, Tobias A1 - Tehei, M. A1 - Zaccai, G. A1 - Büldt, G. A1 - Artmann, Gerhard T1 - From powder to solution : Hydration dependence of human hemoglobin dynamics correlated to body temperature JF - Biophysical Journal. 96 (2009), H. 12 Y1 - 2009 SN - 0006-3495 SP - 5073 EP - 5081 PB - Cell Press CY - Cambridge, Mass. ER - TY - JOUR A1 - Stadler, Andreas M. A1 - Embs, Jan P. A1 - Digel, Ilya A1 - Artmann, Gerhard A1 - Unruh, Tobias A1 - Büldt, Georg A1 - Zaccai, Guiseppe T1 - Cytoplasmic water and hydration layer dynamics in human red blood cells JF - Journal of the American Chemical Society. 50 (2008), H. 130 Y1 - 2008 SN - 1520-5126 SP - 16852 EP - 16853 ER - TY - JOUR A1 - Stadler, Andreas M. A1 - Garvey, G. J. A1 - Bocahut, A. A1 - Sacquin-Mora, S. A1 - Digel, Ilya A1 - Schneider, G. J. A1 - Natali, F. A1 - Artmann, Gerhard A1 - Zaccai, G. T1 - Thermal fluctuations of haemoglobin from different species : adaptation to temperature via conformational dynamics JF - Journal of the Royal Society Interface N2 - Thermodynamic stability, configurational motions and internal forces of haemoglobin (Hb) of three endotherms (platypus, Ornithorhynchus anatinus; domestic chicken, Gallus gallus domesticus and human, Homo sapiens) and an ectotherm (salt water crocodile, Crocodylus porosus) were investigated using circular dichroism, incoherent elastic neutron scattering and coarse-grained Brownian dynamics simulations. The experimental results from Hb solutions revealed a direct correlation between protein resilience, melting temperature and average body temperature of the different species on the 0.1 ns time scale. Molecular forces appeared to be adapted to permit conformational fluctuations with a root mean square displacement close to 1.2 Å at the corresponding average body temperature of the endotherms. Strong forces within crocodile Hb maintain the amplitudes of motion within a narrow limit over the entire temperature range in which the animal lives. In fully hydrated powder samples of human and chicken, Hb mean square displacements and effective force constants on the 1 ns time scale showed no differences over the whole temperature range from 10 to 300 K, in contrast to the solution case. A complementary result of the study, therefore, is that one hydration layer is not sufficient to activate all conformational fluctuations of Hb in the pico- to nanosecond time scale which might be relevant for biological function. Coarse-grained Brownian dynamics simulations permitted to explore residue-specific effects. They indicated that temperature sensing of human and chicken Hb occurs mainly at residues lining internal cavities in the β-subunits. Y1 - 2012 U6 - http://dx.doi.org/10.1098/rsif.2012.0364 SN - 1742-5689 VL - 9 IS - 76 SP - 2845 EP - 2855 PB - The Royal Society CY - London ER - TY - JOUR A1 - Stadler, Andreas M. A1 - Zerlin, Kay A1 - Digel, Ilya A1 - Büldt, Georg A1 - Zaccai, Guiseppe A1 - Artmann, Gerhard T1 - Dynamics and interactions of hemoglobin in red blood cells JF - Tissue Engineering Part A. 14 (2008), H. 5 Y1 - 2008 SN - 1937-3341 N1 - TERMIS EU 2008 Porto Meeting June 22–26, 2008 Porto Congress Center–Alfândega Portugal SP - 724 EP - 724 ER - TY - JOUR A1 - Steinseifer, Ulrich A1 - Kashefi, Ali A1 - Hormes, Marcus A1 - Schoberer, Mark A1 - Orlikowsky, Thorsten A1 - Behbahani, Mehdi A1 - Behr, Marek A1 - Schmitz-Rode, Thomas T1 - Miniaturization of ECMO Systems : Engineering Challenges and Methods JF - Artificial Organs. 33 (2009), H. 5 Y1 - 2009 SN - 1525-1594 N1 - Fifth International Conference on Pediatric Mechanical Circulatory Support Systems and Pediatric Cardiopulmonary Perfusion Abstracts SP - A55 EP - A55 ER - TY - JOUR A1 - Streese, Lukas A1 - Kotliar, Konstantin A1 - Deiseroth, Arne A1 - Infanger, Denis A1 - Gugleta, Konstantin A1 - Schmaderer, Christoph A1 - Hanssen, Henner T1 - Retinal endothelial function in cardiovascular risk patients: A randomized controlled exercise trial JF - Scandinavian Journal of Medicine and Science in Sports N2 - The aim of this study was to investigate, for the first time, the effects of high-intensity interval training (HIIT) on retinal microvascular endothelial function in cardiovascular (CV) risk patients. In the randomized controlled trial, middle-aged and previously sedentary patients with increased CV risk (aged 58 ± 6 years) with ≥ two CV risk factors were randomized into a 12-week HIIT (n = 33) or control group (CG, n = 36) with standard physical activity recommendations. A blinded examiner measured retinal endothelial function by flicker light-induced maximal arteriolar (ADmax) and venular (VDmax) dilatation as well as the area under the arteriolar (AFarea) and venular (VFarea) flicker curve using a retinal vessel analyzer. Standardized assessments of CV risk factors, cardiorespiratory fitness, and retinal endothelial function were performed before and after HIIT. HIIT reduced body mass index, fat mass, and low-density lipoprotein and increased muscle mass and peak oxygen uptake (VO2peak). Both ADmax (pre: 2.7 ± 2.1%, post: 3.0 ± 2.2%, P = .018) and AFarea (pre: 32.6 ± 28.4%*s, post: 37.7 ± 30.6%*s, P = .016) increased after HIIT compared with CG (ADmax, pre: 3.2 ± 1.8%, post: 2.9 ± 1.8%, P = .254; AFarea, pre: 41.6 ± 28.5%*s, post: 37.8 ± 27.0%*s, P = .186). Venular function remained unchanged after HIIT. There was a significant association between ∆-change VO2peak and ∆-changes ADmax and AFarea (P = .026, R² = 0.073; P = .019, R² = 0.081, respectively). 12-weeks of HIIT improved retinal endothelial function in middle-aged patients with increased CV risk independent of the reduction in classical CV risk factors. Exercise has the potential to reverse or at least postpone progression of small vessel disease in older adults with increased CV risk under standard medication. Dynamic retinal vessel analysis seems to be a sensitive tool to detect treatment effects of exercise interventions on retinal microvascular endothelial function in middle-aged individuals with increased CV risk. Y1 - 2020 U6 - http://dx.doi.org/10.1111/sms.13560 SN - 1600-0838 VL - 30 IS - 2 SP - 272 EP - 280 PB - Wiley CY - Oxford ER - TY - JOUR A1 - Stäudle, Benjamin A1 - Seynnes, Olivier A1 - Laps, Guido A1 - Brüggemann, Gert-Peter A1 - Albracht, Kirsten T1 - Altered gastrocnemius contractile behavior in former achilles tendon rupture patients during walking JF - Frontiers in Physiology N2 - Achilles tendon rupture (ATR) remains associated with functional limitations years after injury. Architectural remodeling of the gastrocnemius medialis (GM) muscle is typically observed in the affected leg and may compensate force deficits caused by a longer tendon. Yet patients seem to retain functional limitations during—low-force—walking gait. To explore the potential limits imposed by the remodeled GM muscle-tendon unit (MTU) on walking gait, we examined the contractile behavior of muscle fascicles during the stance phase. In a cross-sectional design, we studied nine former patients (males; age: 45 ± 9 years; height: 180 ± 7 cm; weight: 83 ± 6 kg) with a history of complete unilateral ATR, approximately 4 years post-surgery. Using ultrasonography, GM tendon morphology, muscle architecture at rest, and fascicular behavior were assessed during walking at 1.5 m⋅s–1 on a treadmill. Walking patterns were recorded with a motion capture system. The unaffected leg served as control. Lower limbs kinematics were largely similar between legs during walking. Typical features of ATR-related MTU remodeling were observed during the stance sub-phases corresponding to series elastic element (SEE) lengthening (energy storage) and SEE shortening (energy release), with shorter GM fascicles (36 and 36%, respectively) and greater pennation angles (8° and 12°, respectively). However, relative to the optimal fascicle length for force production, fascicles operated at comparable length in both legs. Similarly, when expressed relative to optimal fascicle length, fascicle contraction velocity was not different between sides, except at the time-point of peak series elastic element (SEE) length, where it was 39 ± 49% lower in the affected leg. Concomitantly, fascicles rotation during contraction was greater in the affected leg during the whole stance-phase, and architectural gear ratios (AGR) was larger during SEE lengthening. Under the present testing conditions, former ATR patients had recovered a relatively symmetrical walking gait pattern. Differences in seen AGR seem to accommodate the profound changes in MTU architecture, limiting the required fascicle shortening velocity. Overall, the contractile behavior of the GM fascicles does not restrict length- or velocity-dependent force potentials during this locomotor task. KW - tendon rupture KW - muscle fascicle behavior KW - walking gait KW - force generation KW - ultrasound imaging Y1 - 2022 U6 - http://dx.doi.org/10.3389/fphys.2022.792576 SN - 1664-042X VL - 13 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Stäudle, Benjamin A1 - Seynnes, Olivier A1 - Laps, Guido A1 - Göll, Fabian A1 - Brüggemann, Gert-Peter A1 - Albracht, Kirsten T1 - Recovery from achilles tendon repair: a combination of Postsurgery Outcomes and Insufficient remodeling of muscle and tendon JF - Medicine & Science in Sports & Exercise N2 - Achilles tendon rupture (ATR) patients have persistent functional deficits in the triceps surae muscle–tendon unit (MTU). The complex remodeling of the MTU accompanying these deficits remains poorly understood. The purpose of the present study was to associate in vivo and in silico data to investigate the relations between changes inMTU properties and strength deficits inATR patients. Methods: Elevenmale subjects who had undergone surgical repair of complete unilateral ATR were examined 4.6 ± 2.0 (mean ± SD) yr after rupture. Gastrocnemius medialis (GM) tendon stiffness, morphology, and muscle architecture were determined using ultrasonography. The force–length relation of the plantar flexor muscles was assessed at five ankle joint angles. In addition, simulations (OpenSim) of the GM MTU force–length properties were performed with various iterations of MTU properties found between the unaffected and the affected side. Results: The affected side of the patients displayed a longer, larger, and stiffer GM tendon (13% ± 10%, 105% ± 28%, and 54% ± 24%, respectively) compared with the unaffected side. The GM muscle fascicles of the affected side were shorter (32% ± 12%) and with greater pennation angles (31% ± 26%). A mean deficit in plantarflexion moment of 31% ± 10% was measured. Simulations indicate that pairing an intact muscle with a longer tendon shifts the optimal angular range of peak force outside physiological angular ranges, whereas the shorter muscle fascicles and tendon stiffening seen in the affected side decrease this shift, albeit incompletely. Conclusions: These results suggest that the substantial changes in MTU properties found in ATR patients may partly result from compensatory remodeling, although this process appears insufficient to fully restore muscle function. KW - Tendon Rupture KW - Stiffness KW - Simulation KW - Muscle Force KW - Muscle Fascicle Y1 - 2021 U6 - http://dx.doi.org/10.1249/MSS.0000000000002592 SN - 1530-0315 VL - 53 IS - 7 SP - 1356 EP - 1366 PB - American College of Sports Medicine CY - Philadelphia, Pa. ER - TY - JOUR A1 - Temiz Artmann, Aysegül A1 - Akhisaroglu, M. A1 - Sercan, Z. A1 - Kayatekin, B. M. T1 - Adhesion of Erythrocytes to Endothelial Cells After Acute Exercise: Differences in Red Blood Cells from Juvenile and Adult Rats. Temiz Artmann, A.; Akhisaroglu, M.; Sercan, Z.; Kayatekin, BM.; Yorukoglu, K.; Kirkali, G. JF - Physiological Research (2005) Y1 - 2005 SN - 0862-8408 N1 - pre-press article ER - TY - JOUR A1 - Temiz Artmann, Aysegül A1 - Cavdar, C. A1 - Yenicerioglu, Y. A1 - Caliskan, S. T1 - The effects of intravenous iron treatment on oxidant stress and erythrocyte deformability in haemodialysis patients. Cavdar, C.; Temiz, A.; Yenicerioglu, Y.; Caliskan, S.; Celik, A.; Sifil, A.; Onvural, B.; Camsari, T. JF - Scandinavian Journal of Urology and Nephrology. 37 (2003), H. 1 Y1 - 2003 SN - 0036-5599 SP - 77 EP - 82 ER - TY - JOUR A1 - Temiz Artmann, Aysegül A1 - Kayatekin, Muammer B. A1 - Uysal, N. A1 - Resmi, H. T1 - Does antioxidant supplementation alter the effects of acute exercise on erythrocyte aggregation, deformability and endothelium adhesion in untrained rats? Kayatekin, Muammer B.; Uysal N.; Resmi, H.; Bediz, Seref C.; Temiz Artmann, A.; Genç, S.; Tugyan, K. JF - International Journal for Vitamin and Nutrition Research. 75 (2005), H. 4 Y1 - 2005 SN - 0300-9831 SP - 243 EP - 250 ER - TY - JOUR A1 - Temiz Artmann, Aysegül A1 - Kayser, Peter T1 - Why is Sepsis an Ongoing Clinical Challenge? Lipopolysaccharide Effects on Red Blood Cell Volume / Temiz, Aysegül ; Kayser, Peter JF - Bioengineering in Cell and Tissue Research / Artmann, Gerhard M. ; Chien, Shu (Eds.) Y1 - 2008 SN - 978-3-540-75408-4 SP - 497 EP - 508 PB - Springer CY - Berlin ER - TY - JOUR A1 - Temiz Artmann, Aysegül A1 - Kurulgan demirci, Eylem A1 - Fırat, Ipek Seda A1 - Oflaz, Hakan A1 - Artmann, Gerhard T1 - Recombinant activated protein C (rhAPC) affects lipopolysaccharide-induced mechanical compliance changes and beat frequency of mESC-derived cardiomyocyte monolayers JF - SHOCK KW - Septic cardiomyopathy KW - LPS KW - cardiomyocyte biomechanics KW - CellDrum KW - actin cytoskeleton Y1 - 2021 U6 - http://dx.doi.org/10.1097/SHK.0000000000001845 SN - 1540-0514 PB - Wolters Kluwer CY - Köln ER - TY - JOUR A1 - Temiz Artmann, Aysegül A1 - Linder, Peter A1 - Kayser, Peter A1 - Digel, Ilya T1 - NMR in vitro effects on proliferation, apoptosis, and viability of human chondrocytes and osteoblasts JF - Methods and findings in Experimental and Clinical Pharmacology. 27 (2005), H. 6 Y1 - 2005 SN - 0379-0355 SP - 391 EP - 394 ER - TY - JOUR A1 - Temiz Artmann, Aysegül A1 - Resmi, Halil A1 - Akhunlar, Hülya A1 - Güner, Gül T1 - In vitro effects of high glucose concentrations on membrane protein sulfhydryl oxidation, G-actin and deformability of human erythrocytes. Resmi, Halil ; Akhunlar, Hülya ; Temiz Artmann, Aysegül ; Güner, Gül JF - Cell biochemistry and function. 23 (2005), H. 3 Y1 - 2005 SN - 0263-6484 SP - 163 EP - 168 ER - 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 - JOUR A1 - Temiz Artmann, Aysegül A1 - Yalcin, Ozlem A1 - Resmi, Halil A1 - Baskurt, Oguz K. T1 - Can white blood cell activation be one of the major factors that affect hemorheological parameters during and after exercise? JF - Clinical Hemorheology and Microcirculation. 26 (2002), H. 3 Y1 - 2002 SN - 1386-0291 N1 - = The 11th European Symposium on Clinical Hemorheology, Rouen, France, 19-22 September 2000 SP - 189 EP - 193 ER - TY - JOUR A1 - Thiebes, Anja Lena A1 - Klein, Sarah A1 - Zingsheim, Jonas A1 - Möller, Georg H. A1 - Gürzing, Stefanie A1 - Reddemann, Manuel A. A1 - Behbahani, Mehdi A1 - Cornelissen, Christian G. T1 - Effervescent atomizer as novel cell spray technology to decrease the gas-to-liquid ratio JF - pharmaceutics N2 - Cell spraying has become a feasible application method for cell therapy and tissue engineering approaches. Different devices have been used with varying success. Often, twin-fluid atomizers are used, which require a high gas velocity for optimal aerosolization characteristics. To decrease the amount and velocity of required air, a custom-made atomizer was designed based on the effervescent principle. Different designs were evaluated regarding spray characteristics and their influence on human adipose-derived mesenchymal stromal cells. The arithmetic mean diameters of the droplets were 15.4–33.5 µm with decreasing diameters for increasing gas-to-liquid ratios. The survival rate was >90% of the control for the lowest gas-to-liquid ratio. For higher ratios, cell survival decreased to approximately 50%. Further experiments were performed with the design, which had shown the highest survival rates. After seven days, no significant differences in metabolic activity were observed. The apoptosis rates were not influenced by aerosolization, while high gas-to-liquid ratios caused increased necrosis levels. Tri-lineage differentiation potential into adipocytes, chondrocytes, and osteoblasts was not negatively influenced by aerosolization. Thus, the effervescent aerosolization principle was proven suitable for cell applications requiring reduced amounts of supplied air. This is the first time an effervescent atomizer was used for cell processing. KW - tri-lineage differentiation KW - survival KW - twin-fluid atomizer KW - adipose-derived stromal cells (ASCs) KW - cell atomization KW - cell aerosolization Y1 - 2022 U6 - http://dx.doi.org/10.3390/pharmaceutics14112421 N1 - This article belongs to the Special Issue "Stromal, Stem, Signaling Cells: The Multiple Roles and Applications of Mesenchymal Cells" VL - 14 IS - 11 PB - MDPI CY - Basel ER - TY - JOUR A1 - Topçu, Murat A1 - Madabhushi, Gopal S.P. A1 - Staat, Manfred T1 - A generalized shear-lag theory for elastic stress transfer between matrix and fibres having a variable radius JF - International Journal of Solids and Structures N2 - A generalized shear-lag theory for fibres with variable radius is developed to analyse elastic fibre/matrix stress transfer. The theory accounts for the reinforcement of biological composites, such as soft tissue and bone tissue, as well as for the reinforcement of technical composite materials, such as fibre-reinforced polymers (FRP). The original shear-lag theory proposed by Cox in 1952 is generalized for fibres with variable radius and with symmetric and asymmetric ends. Analytical solutions are derived for the distribution of axial and interfacial shear stress in cylindrical and elliptical fibres, as well as conical and paraboloidal fibres with asymmetric ends. Additionally, the distribution of axial and interfacial shear stress for conical and paraboloidal fibres with symmetric ends are numerically predicted. The results are compared with solutions from axisymmetric finite element models. A parameter study is performed, to investigate the suitability of alternative fibre geometries for use in FRP. KW - Natural fibres KW - Polymer-matrix composites KW - Biocomposites KW - Stress concentrations KW - Finite element analysis Y1 - 2022 U6 - http://dx.doi.org/10.1016/j.ijsolstr.2022.111464 SN - 0020-7683 VL - 239–240 IS - Art. No. 111464 PB - Elsevier CY - New York, NY ER -