Read by QxMD icon Read

Biomechanics and Modeling in Mechanobiology

Zong-Zheng Chen, Wei-Mo Yuan, Cheng Xiang, De-Pei Zeng, Bo Liu, Kai-Rong Qin
Intracellular calcium dynamics plays an important role in the regulation of vascular endothelial cellular functions. In order to probe the intracellular calcium dynamic response under synergistic effect of wall shear stress (WSS) and adenosine triphosphate (ATP) signals, a novel microfluidic device, which provides the adherent vascular endothelial cells (VECs) on the bottom of microchannel with WSS signal alone, ATP signal alone, and different combinations of WSS and ATP signals, is proposed based upon the principles of fluid mechanics and mass transfer...
September 6, 2018: Biomechanics and Modeling in Mechanobiology
Adela Capilnasiu, Myrianthi Hadjicharalambous, Daniel Fovargue, Dharmesh Patel, Ondrej Holub, Lynne Bilston, Hazel Screen, Ralph Sinkus, David Nordsletten
Characterisation of soft tissue mechanical properties is a topic of increasing interest in translational and clinical research. Magnetic resonance elastography (MRE) has been used in this context to assess the mechanical properties of tissues in vivo noninvasively. Typically, these analyses rely on linear viscoelastic wave equations to assess material properties from measured wave dynamics. However, deformations that occur in some tissues (e.g. liver during respiration, heart during the cardiac cycle, or external compression during a breast exam) can yield loading bias, complicating the interpretation of tissue stiffness from MRE measurements...
August 27, 2018: Biomechanics and Modeling in Mechanobiology
Rohit Y Dhume, Elizabeth D Shih, Victor H Barocas
Fatigue as a mode of failure becomes increasingly relevant with age in tissues that experience repeated fluctuations in loading. While there has been a growing focus on the mechanics of networks of collagen fibers, which are recognized as the predominant mechanical components of soft tissues, the network's fatigue behavior has received less attention. Specifically, it must be asked (1) how the fatigue of networks differs from that of its component fibers, and (2) whether this difference in fatigue behaviors is affected by changes in the network's architecture...
August 27, 2018: Biomechanics and Modeling in Mechanobiology
Zhou Zhou, Xiaogai Li, Svein Kleiven
Traumatic brain injury is a leading cause of disability and mortality. Finite element-based head models are promising tools for enhanced head injury prediction, mitigation and prevention. The reliability of such models depends heavily on adequate representation of the brain-skull interaction. Nevertheless, the brain-skull interface has been largely simplified in previous three-dimensional head models without accounting for the fluid behaviour of the cerebrospinal fluid (CSF) and its mechanical interaction with the brain and skull...
August 27, 2018: Biomechanics and Modeling in Mechanobiology
Solmaz Farzaneh, Olfa Trabelsi, Stéphane Avril
Aortic dissection is the most common catastrophe of the thoracic aorta, with a very high rate of mortality. Type A dissection is often associated with an ascending thoracic aortic aneurysm (ATAA). However, it is widely acknowledged that the risk of type A dissection cannot be reliably predicted simply by measuring the ATAA diameter and there is a pressing need for more reliable risk predictors. It was previously shown that there is a significant correlation between a rupture criterion based on the ultimate stretch of the ATAA and the local extensional stiffness of the aorta...
August 25, 2018: Biomechanics and Modeling in Mechanobiology
Orla M McGee, Paul S Gunning, Adrian McNamara, Laoise M McNamara
It has been proposed that inappropriate positioning of transcatheter aortic valves (TAVs) is associated with procedural complications and decreased device durability. Second-generation TAVs allow for repositioning giving greater control over the final deployment position. However, the impact of positioning on the tissue surrounding these devices needs to be better understood, in particular for the interleaflet triangle in which the conductance system (bundle of His) resides. In this study, we investigate the impact of implantation depth on the frame-tissue interaction for a next-generation repositionable Lotus™ valve...
August 20, 2018: Biomechanics and Modeling in Mechanobiology
Z Xu, C Kleinstreuer
Nanodrug transport in tumor microvasculature and deposition/extravasation into tumor tissue are an important link in the nanodrug delivery process. Considering heterogeneous blood flow, such a dual process is numerically studied. The hematocrit distribution is solved by directly considering the forces experienced by the red blood cells (RBCs), i.e., the wall lift force and the random cell collision force. Using a straight microvessel as a test bed, validated computer simulations are performed to determine blood flow characteristics as well as the resulting nanodrug distribution and extravasation...
August 13, 2018: Biomechanics and Modeling in Mechanobiology
Lingling Wei, Qiang Chen, Zhiyong Li
This work aims to investigate the effects of plaque eccentricity and composition on the stent performance and stress distributions of plaque and artery during stenting by the finite element method. Three-dimensional stent-plaque-artery models for plaques with five different eccentricities and four different compositions were simulated, and the influences on stent recoil, stent plastic strain, stent foreshortening, stress distributions of artery and plaque, and lumen gain were studied. The results show that greater plaque eccentricity leads to greater stent recoil, stent plastic strain, stent foreshortening, maximum von Mises stresses of artery and plaque, and volume percentage of plaque in higher stress...
August 10, 2018: Biomechanics and Modeling in Mechanobiology
Daniel Salinas, Brendan M Mumey, Ronald K June
Chondrocytes use the pathways of central metabolism to synthesize molecular building blocks and energy for cartilage homeostasis. An interesting feature of the in vivo chondrocyte environment is the cyclical loading generated in various activities (e.g., walking). However, it is unknown whether central metabolism is altered by mechanical loading. We hypothesized that physiological dynamic compression alters central metabolism in chondrocytes to promote production of amino acid precursors for matrix synthesis...
August 10, 2018: Biomechanics and Modeling in Mechanobiology
Farhad Javid, Nastaran Shahmansouri, Jorge Angeles, Rosaire Mongrain
Sudden failure and rupture of the tissue is a rare but serious short-term complication after the mitral valve surgical repair. Excessive cyclic loading on the suture line of the repair can progressively damage the surrounding tissue and finally cause tissue rupture. Moreover, mechanical over-tension, which occurs in a diseased mitral valve, gradually leads to tissue floppiness, mitral annular dilation, and leaflet rupture. In this work, the rupture mechanics of mitral valve is studied by characterizing the fracture toughness exhaustion of healthy tissue...
August 10, 2018: Biomechanics and Modeling in Mechanobiology
Marc Garbey, Stefano Casarin, Scott A Berceli
Peripheral arterial occlusive disease is a chronic pathology affecting at least 8-12 million people in the USA, typically treated with a vein graft bypass or through the deployment of a stent in order to restore the physiological circulation. Failure of peripheral endovascular interventions occurs at the intersection of vascular biology, biomechanics, and clinical decision making. It is our hypothesis that the majority of endovascular treatment approaches share the same driving mechanisms and that a deep understanding of the adaptation process is pivotal in order to improve the current outcome of the procedure...
August 9, 2018: Biomechanics and Modeling in Mechanobiology
Marco Fielder, Arun K Nair
Bone is a biomaterial with a structural load-bearing function. Investigating the biomechanics of bone at the nanoscale is important in application to tissue engineering, the development of bioinspired materials, and for characterizing factors such as age, trauma, or disease. At the nanoscale, bone is composed of fibrils that are primarily a composite of collagen, apatite crystals (mineral), and water. Though several studies have been done characterizing the mechanics of fibrils, the effects of variation and distribution of water and mineral content in fibril gap and overlap regions are unexplored...
August 7, 2018: Biomechanics and Modeling in Mechanobiology
H Shin, J H Haga, T Kosawada, K Kimura, Y S Li, S Chien, G W Schmid-Schönbein
Recent experimental evidence points to the possibility that cell surface-associated caveolae may participate in mechanotransduction. The particular shape of caveolae suggests that these structures serve to prevent exposure of putative mechanosensors residing within these membrane invaginations to shear stresses at magnitudes associated with initiation of cell signaling. Accordingly, we numerically analyzed the fluid flow in and around caveolae using the equation of motion for flow of plasma at low Reynolds numbers and assuming no slip-condition on the membrane...
August 7, 2018: Biomechanics and Modeling in Mechanobiology
Yilin Zhu
In the present work, a constitutive model for articular cartilage is proposed in finite elasto-viscoplasticity. For simplification, articular cartilage is supposed to be a typical composite composed of a soft basis and a fiber assembly. The stress tensor and free energy function are hence accordingly divided into two components. The high nonlinear stress-strain response is assumed to be mainly related to the fiber assembly and described by an exponential-type hypoelastic relation. Ratcheting is considered according to the viscoplasticity, the evolution rule of which is deduced from the dissipative inequality by the co-directionality hypotheses...
August 4, 2018: Biomechanics and Modeling in Mechanobiology
John D Horn, Duncan J Maitland, Jonathan Hartman, Jason M Ortega
Cardiovascular implantable devices alter the biofluid dynamics and biochemistry of the blood in which they are placed. These perturbations can lead to thrombus formation which may or may not be desired, depending on the application. In this work, a computational model is developed that couples biofluid dynamics and biochemistry to predict the clotting response of blood to such devices. The model consists of 28 advection-diffusion-reaction partial differential equations to track proteins in the blood involved in clotting and utilizes boundary flux terms to model the initiation of the intrinsic clotting pathway at thrombogenic device surfaces...
August 3, 2018: Biomechanics and Modeling in Mechanobiology
Mohamed Amine Chetoui, Olivier Boiron, Moncef Ghiss, Abdelwaheb Dogui, Valérie Deplano
Quantitative magnetic resonance imaging (MRI) provides useful information about intervertebral disc (IVD) biomechanical properties, especially those in relation to the fluid phase. These properties may improve IVD finite element (FE) models using data closer to physiological reality. The aim of this study is to investigate IVD degeneration-related properties using a coupling between MRI and FE modeling. To this end, proton density ([Formula: see text])-weighted MRI sequences of a porcine lumbar IVD were carried out to develop two biphasic swelling models with hyperelastic extracellular matrix behavior...
August 3, 2018: Biomechanics and Modeling in Mechanobiology
Ivan Breslavsky, Marco Amabili
The nonlinear static deformation of human descending thoracic aortic segments is investigated. The aorta segments are modeled as straight axisymmetric circular cylindrical shells with three hyperelastic anisotropic layers and residual stresses by using an advanced nonlinear shell theory with higher-order thickness deformation not available in commercial finite element codes. The residual stresses are evaluated in the closed configuration in an original way making use of the multiplicative decomposition. The model was initially validated through comparison with published numerical and experimental data for artery and aorta segments...
August 2, 2018: Biomechanics and Modeling in Mechanobiology
Taeksang Lee, Sergey Y Turin, Arun K Gosain, Ilias Bilionis, Adrian Buganza Tepole
Excessive mechanical stress following surgery can lead to delayed healing, hypertrophic scars, and even skin necrosis. Measuring stress directly in the operating room over large skin areas is not feasible, and nonlinear finite element simulations have become an appealing alternative to predict stress contours on arbitrary geometries. However, this approach has been limited to generic cases, when in reality each patient geometry and procedure are unique, and material properties change from one person to another...
August 2, 2018: Biomechanics and Modeling in Mechanobiology
Nazanin Maani, Steven W Hetts, Vitaliy L Rayz
Two-scale CFD modeling is used to design and optimize a novel endovascular filtration device for removing toxins from flowing blood. The Chemofilter is temporarily deployed in the venous side of a tumor during the intra-arterial chemotherapy in order to filter excessive chemotherapy drugs such as Doxorubicin from the blood stream. The device chemically binds selective drugs to its surface thus filtering them from blood, after they have had the effect on the tumor and before they reach the heart and other organs...
July 31, 2018: Biomechanics and Modeling in Mechanobiology
Milad Ghasemi, David R Nolan, Caitríona Lally
Carotid atherosclerotic plaque rupture is one of the leading causes of stroke. Treatments for atherosclerosis can induce tissue damage during the deployment of an intravascular device or through external tissue clamping during surgery. In this paper, a constituent specific study was performed to investigate the role of the ground matrix and collagen fibres of arterial tissue in response to supra-physiological loads. Cyclic mechanical tests were conducted on intact and collagenase-digested strips of porcine common carotid arteries...
July 30, 2018: Biomechanics and Modeling in Mechanobiology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"