Guangyu Zhu¹, Yuan Wei¹, Qi Yuan^1,*, Ge Yan², Jian Yang²

Molecular & Cellular Biomechanics, Vol.16, Suppl.1, pp. 55-56, 2019, DOI:10.32604/mcb.2019.05730

Abstract This article has no abstract. More >

Chunbo Jin¹, Youjun Liu^1,*

Molecular & Cellular Biomechanics, Vol.16, Suppl.1, pp. 51-52, 2019, DOI:10.32604/mcb.2019.05728

Abstract Coronary heart disease (CHD) is one of the most common forms of heart disease, which means that coronary stenosis can cause insufficient blood supply to the heart and lead to coronary heart disease. Coronary artery bypass grafting (coronary bypass) is often used in the treatment of patients with coronary heart disease. After surgery, because the stenosis of the coronary artery is not completely occluded, the blood flow through it will compete with the blood flow of the graft, making it possible to transplant blood vessels. The blood flow is affected, reducing long-term permeability. When the coronary artery is completely stenotic,… More >

S. Kobayashi¹, J. Ji¹, H. Morikawa¹, D. Tang², D. N. Ku³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.6, No.3, pp. 169-174, 2008, DOI:10.3970/icces.2008.006.169

Abstract The increase of the blood velocity in the distal side of the stenosis causes negative transmural pressure, and atheroscrerotic plaque is compressed, furthermore, the stenosis may cause the collpase which leads the rupture of the plaque. The resultant compression may be important in the development of atherosclerotic plaque fracture and subsequent thrombosis or distal embolization. We have developed stenosis models made of polyvinyl alcohol hydrogel, which closely approximate an arterial disease situation, and performed pulsatile flow experiments. Valsalva's maneuver and cough cause a sharp rise in jugular venous pressure to greater than 50 mmHg. Such transient pressure increases within the… More >

Xu Zhang^1,‡, Jie Gao^2,‡, Xinke Yao¹, Zhengze Dai^3,4, Gelin Xu^2,*, Yan Cai^1,*, Zhiyong Li^1,5,*

Molecular & Cellular Biomechanics, Vol.16, No.1, pp. 27-39, 2019, DOI:10.32604/mcb.2019.06140

Abstract Digital subtraction angiography (DSA) is often used to evaluate the morphological and pathological changes of cerebral arteries in clinical practice. This study aims to explore the possibility of assessing cerebral hypoperfusion with DSA in patients with carotid stenosis. Thirty patients with a mild to severe stenosis on one side, and a mild stenosis on the other side of the carotid artery were recruited. Frontal, parietal, temporal and occipital lobes were chosen as regions of interest for measuring the quantitative perfusion parameters from their time-density curves (TDCs) of DSA images. The perfusion parameters were compared between the two hemispheres by using… More >

Molecular & Cellular Biomechanics, Vol.15, No.1, pp. 51-61, 2018, DOI:10.3970/mcb.2018.015.051

Abstract Tracheal stenosis is a common respiratory disease and is usually treated by stent implantation. However, the implanted stent often causes excessive hyperplasia of trachea granulation tissue, leading to the restenosis. Although surgical removal or chemical suppression can be used to alleviate the restenosis, the efficacy is limited. Thus, restenosis remains a thorny complication. We investigated this issue from the perspective of the “tress-growth”relationship. Firstly, the lower airway of 5 experimental dogs were CT-scanned to reconstruct the 3D numerical models; secondly, the implantations of the Nitinol alloy stents were numerically simulated; thirdly, 45 days after the stenting, the dogs were evaluated… More >

PoojaJhunjhunwala¹, P.M. Padole², S.B. Thombre³

Molecular & Cellular Biomechanics, Vol.13, No.1, pp. 1-21, 2016, DOI:10.3970/mcb.2016.013.001

Abstract This paper presents Computational fluid dynamic (CFD) analysis of blood flow in three different 3-D models of left coronary artery (LCA). A comparative study of flow parameters (pressure distribution, velocity distribution and wall shear stress) in each of the models is done for a non-Newtonian (Carreau) as well as the Newtonian nature of blood viscosity over a complete cardiac cycle. The difference between these two types of behavior of blood is studied for both transient and steady states of flow. Additionally, flow parameters are compared for steady and transient boundary conditions considering blood as non-Newtonian fluid. The study shows that… More >

P. Jhunjhunwala^∗,†, P.M. Padole^∗,‡, S.B. Thombre^∗,§

Molecular & Cellular Biomechanics, Vol.12, No.1, pp. 37-47, 2015, DOI:10.3970/mcb.2015.012.037

Abstract CFD analysis plays an important role in the area of analysis of blood flow as in-vivo measurements of blood flow is costly and easily not accessible. This paper presents simulation of blood flow in healthy and stenosed coronary artery 2- D models. The simulation was done considering non-Newtonian behavior of blood and pulsatile nature of blood flow which is close to physical scenario. Pressure distribution, velocity distribution and wall shear were examined to understand their effect on Atherosclerosis. More >

Zheng-qi Liu^∗, Ying Liu^∗,†, Tian-tian Liu^∗, Qing-shan Yang^‡

Molecular & Cellular Biomechanics, Vol.11, No.2, pp. 129-149, 2014, DOI:10.3970/mcb.2014.011.129

Abstract In this paper, the hemodynamic characteristics of blood flow and stress distribution in a layered and stenotic aorta are investigated. By introducing symmetrical and unsymmetrical stenosis, the influence of stenosis morphology and stenotic ratio on the coupled dynamic responses of aorta is clarified. In the analysis, the in-vivo pulsatile waveforms and fully fluid–structure interaction (FSI) between the layered elastic aorta and the blood are considered. The results show that the fluid domain is abnormal in the stenotic aorta, and the whirlpool forms at the obstructed and downstream unobstructed regions. The maximum wall shear stresses appear at the throat of the… More >

L. L. Xiao^∗, S. Chen^∗,†, C. S. Lin^∗, Y. Liu^‡

Molecular & Cellular Biomechanics, Vol.11, No.1, pp. 67-85, 2014, DOI:10.3970/mcb.2014.011.067

Abstract The motion and deformation of a single red blood cell flowing through a microvessel stenosis was investigated employing dissipative particle dynamics (DPD) method. The numerical model considers plasma, cytoplasm, the RBC membrane and the microvessel walls, in which a three dimensional coarse-grained spring network model of RBC’s membrane was used to simulate the deformation of the RBC. The suspending plasma was modelled as an incompressible Newtonian fluid and the vessel walls were regarded as rigid body. The body force exerted on the free DPD particles was used to drive the flow. A modified bounce-back boundary condition was enforced on the… More >

Biyue Liu^∗, Dalin Tang^†

Molecular & Cellular Biomechanics, Vol.8, No.1, pp. 73-90, 2011, DOI:10.3970/mcb.2011.008.073

Abstract The objective of this work is to investigate the effect of non-Newtonian properties of blood on the wall shear stress (WSS) in atherosclerotic coronary arteries using both Newtonian and non-Newtonian models. Numerical simulations were performed to examine how the spatial and temporal WSS distributions are influenced by the stenosis size, blood viscosity, and flow rate. The computational results demonstrated that blood viscosity properties had considerable effect on the magnitude of the WSS, especially where disturbed flow was observed. The WSS distribution is highly non-uniform both temporally and spatially, especially in the stenotic region. The maximum WSS occurred at the proximal… More >