Abstract:
BACKGROUND:Dilation and dissection of aneurysmal ascending aortic tissues occur preferentially at the outer curvature of the vessel. In this study we hypothesize that the density and contractile properties of the vascular smooth muscle cells (VSMCs) of the pig ascending aorta (AA) are heterogeneous and could explain the non-uniform remodeling and weakening of the AA during aneurysm formation. METHODS:Eleven pig AA rings were collected. Two square samples of 15 x 15 mm were taken from each ring from the inner and outer curvature of the AA. Each sample was subjected to equi-biaxial tensile testing in Krebs-Ringer solution maintained at 37 degrees C. Each test consisted of 8 cycles of preconditioning followed by one experimental run from 0% to 30% strain. Phenylephrine (10(-5) M) was added to contract VSMCs. After biaxial testing, samples were paraffin-embedded and stained with hematoxylin-phloxine-saffron (HPS) to quantify VSMC density. RESULTS:Significant differences in cell density, maximum contractile stress resultant magnitude (MCSRM) and orientation (theta(MCSR)) were found between the inner and outer curvature. The inner curvature had the greatest contraction. The outer curvature had the highest VSMC density with the maximum contraction stress resultant oriented towards the axial direction. CONCLUSION:VSMC activation with phenylephrine had a significant effect on the stiffness of the pig AA. This effect was independent of location and direction. However, cell orientation, density and contractile properties were dependent on location and suggest variations in the remodeling capabilities, tissue strain and cell phenotype between locations.
journal_name
J Biomechjournal_title
Journal of biomechanicsauthors
Tremblay D,Cartier R,Mongrain R,Leask RLdoi
10.1016/j.jbiomech.2010.04.018subject
Has Abstractpub_date
2010-08-26 00:00:00pages
2448-51issue
12eissn
0021-9290issn
1873-2380pii
S0021-9290(10)00230-7journal_volume
43pub_type
杂志文章abstract::The importance of the aortic root compliance in the aortic valve performance has most frequently been ignored in computational valve modeling, although it has a significant contribution to the functionality of the valve. Aortic root aneurysm or (calcific) stiffening severely affects the aortic valve behavior and, cons...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/s0021-9290(02)00448-7
更新日期:2003-05-01 00:00:00
abstract::In this paper the mechanical response of soft collagenous tissues with regular fiber arrangement (RSCTs) is described by means of a nanoscale model and a two-step micro-macro homogenization technique. The non-linear collagen constitutive behavior is modeled at the nanoscale by a novel approach accounting for entropic ...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2009.07.040
更新日期:2010-01-19 00:00:00
abstract::The ultimate compressive strength and modulus of elasticity of femoral cortical bone from adult geese (Anser anser), were determined by sex and by quadrant by compressing small right circular cylinders which were 2.4 mm in height and 0.8 mm in diameter. The average ultimate compressive strength was 183 +/- 29 MPa. The...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/0021-9290(83)90108-2
更新日期:1983-01-01 00:00:00
abstract::Time-domain-based one-dimensional wave propagation models of the arterial system are preferable over one-dimensional wave propagation models in the frequency domain since the latter neglect the non-linear convection forces present in the physiological situation, especially when the vessel is tapered. Moreover, one-dim...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2007.09.014
更新日期:2008-01-01 00:00:00
abstract::Computational simulations of tissue differentiation have been able to capture the main aspects of tissue formation/regeneration observed in animal experiments-except for the considerable degree of variability reported. Understanding and modelling the source of this variability is crucial if computational tools are to ...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2011.02.003
更新日期:2011-04-07 00:00:00
abstract::A technique was developed to investigate the condylar displacement of the human temporomandibular joint. Condylar displacement was analyzed from magnetic resonance images of the joint. Fourteen static images were obtained during incremental jaw closure. Landmarks were identified on the magnetic resonance images and re...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/0021-9290(93)90096-w
更新日期:1993-12-01 00:00:00
abstract::This study examines the age at which a femoral physeal failure ceased to occur in a mouse model of medial collateral ligament (MCL) testing. Biomechanical testing of the MCL with load to failure can result in physeal failure rather than MCL failure in skeletally immature animals. Failure mode depended significantly on...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2004.05.014
更新日期:2005-04-01 00:00:00
abstract::The nonlinear stress-strain characteristics of the human menisci were determined by uniaxial elongation tests performed on circumferential and radial specimens prepared from different regions, layers, and locations. The properties of the collagen fibers and the matrix were calculated using the test results along with ...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/0021-9290(94)00081-e
更新日期:1995-04-01 00:00:00
abstract::One of the most popular methods to fabricate biomedical microfluidic devices is by using a soft-lithography technique. However, the fabrication of the moulds to produce microfluidic devices, such as SU-8 moulds, usually requires a cleanroom environment that can be quite costly. Therefore, many efforts have been made t...
journal_title:Journal of biomechanics
pub_type: 杂志文章,评审
doi:10.1016/j.jbiomech.2015.11.031
更新日期:2016-07-26 00:00:00
abstract::The topographical distributions of the zonal properties of articular cartilage over the medial tibia from an experimental osteoarthritis (OA) model were evaluated as a function of external loading by microscopic Magnetic Resonance Imaging (µMRI). T2 relaxation times and cartilage thicknesses were measured at 17.6 µm r...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2015.08.011
更新日期:2015-10-15 00:00:00
abstract::Structural properties of articular cartilage such as proteoglycan content, collagen content and collagen alignment are known to vary over length scales as small as a few microns (Bullough and Goodfellow, 1968; Bi et al., 2006). Characterizing the resulting variation in mechanical properties is critical for understandi...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2009.10.012
更新日期:2010-03-03 00:00:00
abstract::The oxidized low-density lipoprotein (Ox-LDL) plays an important role in atherosclerosis, yet it remains unclear if it damages circulating erythrocytes. In this study, erythrocyte deformability and its membrane proteins after Ox-LDL incubations are investigated by micropipette aspiration, thiol radical measurement, an...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2009.05.026
更新日期:2009-10-16 00:00:00
abstract::Arterial embolism is responsible for the death of lots of people who suffers from heart diseases. The major risk of embolism in upper limbs is that the ruptured particles are brought into the brain, thus stimulating neurological symptoms or causing the stroke. We presented a computational model using fluid-structure i...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2012.01.020
更新日期:2012-04-30 00:00:00
abstract::Coronary artery disease results in blockages or narrowing of the artery lumen. Drug eluting stents (DES) were developed to replace bare metal stents in an effort to combat re-blocking of the diseased artery following treatment. The numerical models developed within this study focus on representing the changing trends ...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2013.09.017
更新日期:2014-01-03 00:00:00
abstract::The critical role that mechanical stimuli serve in mediating bone repair is recognized but incompletely understood. Further, previous attempts to understand this role have utilized application of externally applied mechanical loads to study the tissue's response. In this project, we have therefore endeavored to capita...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2010.06.030
更新日期:2010-10-19 00:00:00
abstract::Stair-climbing while doing a concurrent task like talking or holding an object is a common activity of daily living which poses high risk for falls. While biomechanical analyses of overground walking during dual-tasking have been studied extensively, little is known on the biomechanics of stair-climbing while dual-tas...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2015.02.024
更新日期:2015-04-13 00:00:00
abstract::Acute injury severity, altered joint kinematics, and joint incongruity are three important mechanical factors linked to post-traumatic osteoarthritis (PTOA). Finite element analysis (FEA) was previously used to assess the influence of increased contact stress due to joint incongruity on PTOA development. While promisi...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2015.05.030
更新日期:2015-09-18 00:00:00
abstract::A dry-land rowing system was developed to provide the coach and/or athlete with quantitative information about the athlete's kinetics and kinematics while the athlete trains. This system consists of a Concept II rowing ergometer instrumented with a force transducer and potentiometer, four electrogoniometers attached t...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/s0021-9290(99)00139-6
更新日期:2000-02-01 00:00:00
abstract::High-energy synchrotron X-ray scattering (>60 keV) allows noninvasive quantification of internal strains within bone. In this proof-of-principle study, wide angle X-ray scattering maps internal strain vs position in cortical bone (murine tibia, bovine femur) under compression, specifically using the response of the mi...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2010.10.015
更新日期:2011-01-11 00:00:00
abstract::The multi-signal mechanical environment mammalian cells experience is often unaccounted for in current mechanical stimulation studies. To address this we developed a novel technique to induce dual integrated force inputs, uniaxial stretch and fluid shear stress and present here for the first time a vector logic-gate f...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2014.12.047
更新日期:2015-02-26 00:00:00
abstract::The purpose of this study was to test the hypothesis that the musculotendon moment arm length is affected by the muscle anatomical cross-sectional area. The moment arm length of the triceps brachii (TB) muscle at 30°, 50°, 70°, 90°, 110° elbow flexion positions was measured in sagittal magnetic resonance images (MRI) ...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2010.06.013
更新日期:2010-10-19 00:00:00
abstract::The problem of peristaltic transport of blood in a uniform and non-uniform tube has been investigated, under zero Reynolds number and long wavelength approximation. Blood is represented by a two-layered fluid model consisting of a central layer of suspension of all erythrocytes, etc., assumed to be a Casson fluid, and...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/0021-9290(84)90140-4
更新日期:1984-01-01 00:00:00
abstract::Sitting is often assumed to involve high loads on the spine as well as on implants for stabilising the spine. Loads on internal spinal fixation devices were therefore measured in ten patients sitting on several types of seats, including a stool, a stool with a padded wedge, a chair, a physiotherapy ball, a knee-stool,...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/s0021-9290(01)00073-2
更新日期:2001-08-01 00:00:00
abstract::The purpose of this investigation was to determine the feasibility of using a single inertial measurement unit (IMU) placed on the sacrum to estimate 3-dimensional ground reaction force (F) during linear acceleration and change of direction tasks. Force plate measurements of F and estimates from the proposed IMU metho...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2017.07.035
更新日期:2017-08-16 00:00:00
abstract::Significant ground reaction forces exceeding body weight occur during the heel-strike phase of gait. The standard methods of analytical dynamics used to solve the impact problem do not accommodate well the heel-strike collision due to the persistent contact at the front foot and presence of contact at the back foot. T...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/s0021-9290(00)00006-3
更新日期:2000-06-01 00:00:00
abstract::In this study, the dynamic compressive properties in five different regions of the porcine temporomandibular joint (TMJ) disc are investigated over a wide range of loading frequencies. The aim was, thus far, to evaluate the regional difference and the frequency-related effect of the applied load on these properties. E...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2012.11.035
更新日期:2013-02-22 00:00:00
abstract::In this paper, a novel multi-slice ultrasound (US) image calibration of an intelligent skin-marker used for soft tissue artefact compensation is proposed to align and orient image slices in an exact H-shaped pattern. Multi-slice calibration is complex, however, in the proposed method, a phantom based visual alignment ...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2016.12.030
更新日期:2017-09-06 00:00:00
abstract::The effect of tendons viscoelastic stiffness on the dynamic response of the cat's tibialis anterior muscle under isometric conditions was determined. It was shown that the dynamic response model of the muscle derived under sinusoidal contraction-relaxation in the range of 20-80% of its maximal isometric tension was no...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/0021-9290(91)90355-q
更新日期:1991-01-01 00:00:00
abstract::Strength, or maximum joint torque, is a fundamental factor governing human movement, and is regularly assessed for clinical and rehabilitative purposes as well as for research into human performance. This study aimed to identify the most appropriate protocol for fitting a maximum voluntary torque function to experimen...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2010.11.024
更新日期:2011-03-15 00:00:00
abstract::Incisional hernia development is a significant complication after laparoscopic abdominal surgery. Intra-abdominal pressure (IAP) is known to initiate the extrusion of intestines through the abdominal wall, but there is limited data on the mechanics of IAP generation and the structural properties of rectus sheath. This...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2014.03.009
更新日期:2014-06-03 00:00:00