Open Access
ARTICLE
Sangho Kim∗,†, Peng Kai Ong*, Paul C. Johnson‡
Molecular & Cellular Biomechanics, Vol.6, No.2, pp. 83-92, 2009, DOI:10.3970/mcb.2009.006.083
Abstract Recently, we reported that collision efficiency (fraction of total collisions that result in the formation of aggregates) between red blood cells was an important factor in the formation of aggregates in postcapillary venules. In the present study, we focus on how high molecular weight dextran influences the overall radial migration trend of red blood cells in the postcapillary venule along a longitudinal distance of 50 μm from the bifurcation which would in turn affect collision behavior of these cells. A radial migration index, which defines the extent of radial migration of individual cells relative to the vessel center, was found… More >
Open Access
ARTICLE
Hai-Chao Han†
Molecular & Cellular Biomechanics, Vol.6, No.2, pp. 93-100, 2009, DOI:10.3970/mcb.2009.006.093
Abstract Though tortuosity and kinking are often observed in various arteries and arterioles, little is known about the underlying mechanisms. This paper presents a biomechanical analysis of bent buckling in long arterial segments with a small initial curvature using a thick-walled elastic cylindrical arterial model. The critical buckling pressure was established as a function of wall stiffness, wall dimensions, and the axial tension (or axial stretch ratio). The effects of both wall dimensions and axial stretch ratio on the critical pressure, as well as the thin-walled approximation were discussed. The buckling equation sheds light on the biomechanical mechanism of artery tortuosity… More >
Open Access
ARTICLE
Yanan Wang∗, Qing-Hua Qin∗, Shankar Kalyanasundaram∗
Molecular & Cellular Biomechanics, Vol.6, No.2, pp. 101-112, 2009, DOI:10.3970/mcb.2009.006.101
Abstract A mathematical model is developed for simulating anabolic behaviour of bone affected by Parathyroid Hormone (PTH) in this paper. The model incorporates a new understanding on the interaction of PTH and other factors with the RANK-RANKL-OPG pathway into bone remodelling, which is able to simulate anabolic actions of bone induced by PTH at cellular level. The RANK-RANKL-OPG pathway together with the dual action of TGF-$\beta$, which represent the core of coupling behaviour between osteoblasts and osteoclasts which are two cell types specialising in the maintenance of bone integrity, are widely considered essential for the regulation of bone remodelling at cellular… More >
Open Access
ARTICLE
Nikolai Steklov*, Ajay Srivastava*, K.L.P. Sung†, Peter C. Chen†, Martin K. Lotz*, Darryl D. D’Lima‡
Molecular & Cellular Biomechanics, Vol.6, No.2, pp. 113-119, 2009, DOI:10.3970/mcb.2009.006.113
Abstract The biomechanical properties of articular cartilage change profoundly with aging. These changes have been linked with increased potential for cartilage degeneration and osteoarthritis. However, less is known about the change in biomechanical properties of chondrocytes with increasing age. Cell stiffness can affect mechanotransduction pathways and may alter cell function. We measured aging-related changes in the biomechanical properties of chondrocytes. Human chondrocytes were isolated from knee articular cartilage within 48 hours after death or from osteochondral specimens obtained from knee arthroplasty. Cells were divided into two age groups: between 18 and 35 years (18 -- 35); and greater than 55 years… More >
Open Access
ARTICLE
Xueying Huang*, Chun Yang†, Chun Yuan‡, Fei Liu‡, Gador Canton‡, Jie Zheng§, Pamela K. Woodard§, Gregorio A. Sicard¶, Dalin Tang||
Molecular & Cellular Biomechanics, Vol.6, No.2, pp. 121-134, 2009, DOI:10.3970/mcb.2009.006.121
Abstract Image-based computational models for atherosclerotic plaques have been developed to perform mechanical analysis to quantify critical flow and stress/strain conditions related to plaque rupture which often leads directly to heart attack or stroke. An important modeling issue is how to determine zero stress state from in vivo plaque geometries. This paper presents a method to quantify human carotid artery axial and inner circumferential shrinkages by using patient-specific ex vivo and in vivo MRI images. A shrink-stretch process based on patient-specific in vivo plaque morphology and shrinkage data was introduced to shrink the in vivo geometry first to find the zero-stress… More >