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Christopher A. Lemmon^1,2, Nathan J. Sniadecki³, Sami Alom Ruiz^1,3, John L. Tan, Lewis H. Romer^2,4,5, Christopher S. Chen^3,4
Molecular & Cellular Biomechanics, Vol.2, No.1, pp. 1-16, 2005, DOI:10.3970/mcb.2005.002.001
Abstract The interplay of mechanical forces between the extracellular environment and the cytoskeleton drives development, repair, and senescence in many tissues. Quantitative definition of these forces is a vital step in understanding cellular mechanosensing. Microfabricated post array detectors (mPADs) provide direct measurements of cell-generated forces during cell adhesion to extracellular matrix. A new approach to mPAD post labeling, volumetric imaging, and an analysis of post bending mechanics determined that cells apply shear forces and not point moments at the matrix interface. In addition, these forces could be accurately resolved from post deflections by using images of post tops and bases. Image… More >

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ARTICLE

Nan Shen^1,2, Dabajyoti Datta¹, Chris B. Schaffer^1,3,4,5, Eric Mazur^1,6
Molecular & Cellular Biomechanics, Vol.2, No.1, pp. 17-26, 2005, DOI:10.3970/mcb.2005.002.017
Abstract Analysis of cell regulation requires methods for perturbing molecular processes within living cells with spatial discrimination on the nanometer-scale. We present a technique for ablating molecular structures in living cells using low-repetition rate, low-energy femtosecond laser pulses. By tightly focusing these pulses beneath the cell membrane, we ablate cellular material inside the cell through nonlinear processes. We selectively removed sub-micrometer regions of the cytoskeleton and individual mitochondria without altering neighboring structures or compromising cell viability. This nanoscissor technique enables non-invasive manipulation of the structural machinery of living cells with several-hundred-nanometer resolution. Using this approach, we unequivocally demonstrate that mitochondria are… More >

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K. Y. Volokh ^{1, 2} , Y. Lev³
Molecular & Cellular Biomechanics, Vol.2, No.1, pp. 27-40, 2005, DOI:10.3970/mcb.2005.002.027
Abstract A simple phenomenological theory of tissue growth is used in order to demonstrate that volumetric growth combined with material anisotropy can lead to accumulation of residual stresses in arteries. The theory is applied to growth of a cylindrical blood vessel with the anisotropy moduli derived from experiments. It is shown that bending resultants are developed in the ring cross-section of the artery. These resultants may cause the ring opening or closing after cutting the artery \textit {in vitro} as it is observed in experiments. It is emphasized that the mode of the arterial ring opening is affected by the parameters… More >

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643

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Wei Zhang^1,2, Carly Herrera¹, Satya N. Atluri¹, Ghassan S. Kassab^2,3
Molecular & Cellular Biomechanics, Vol.2, No.1, pp. 41-52, 2005, DOI:10.3970/mcb.2005.002.041
Abstract It is well known that blood vessels shorten axially when excised. This is due to the perivascular tethering constraint by side branches and the existence of pre-stretch of blood vessels at the \textit {in situ} state. Furthermore, vessels are radially constrained to various extents by the surrounding tissues at physiological loading. Our hypothesis is that the axial pre-stretch and radial constraint by the surrounding tissue homogenizes the stress and strain distributions in the vessel wall. A finite element analysis of porcine coronary artery and rabbit thoracic aorta based on measured material properties, geometry, residual strain and physiological loading is used… More >

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