Cells can sense and respond to mechanical signals over relatively long distances across fibrous extracellular matrices. Recently proposed models suggest that long-range force transmission can be attributed to the nonlinear elasticity or fibrous nature of collagen matrices, yet the mechanism whereby fibers align remains unknown. Moreover, cell shape and anisotropy of cellular contraction are not...

We describe 3D single particle tracking of gold nanoparticles (AuNPs) moving along collagen fibers in aqueous environment with two-photon excitation conditions. The photoacoustic effect at the collagen fiber caused by the irradiation with ultrashort, near-infrared laser pulses propels the particles adsorbed to the surface of the collagen fibers. We report the tracking of individual AuNPs in thr...

BACKGROUND Mammary gland morphogenesis involves ductal elongation, branching, and budding. All of these processes are mediated by stroma--epithelium interactions. Biomechanical factors, such as matrix stiffness, have been established as important factors in these interactions. For example, epithelial cells fail to form normal acinar structures in vitro in 3D gels that exceed the stiffness of a ...

Introduction: The load-dependent collageneous fiber organization in the joint cartilage determines the biomechanical properties of this tissue. It has been shown that the deformation mechanisms of the collagen network under compressive load depend on the morphological and structural intactness of the cartilage [1, 2]. Thus, the analysis of load-reactions of joint cartilage could be a successful...

PURPOSE Previous studies have suggested that the lamina cribrosa (LC) and its surrounding sclera are biomechanically important in the pathogenesis of glaucoma, but many were limited by assumptions of tissue isotropy and homogeneity. Here, we used an improved biomechanical model driven by experimental measurements of scleral and LC collagen fiber organization to more accurately evaluate optic ne...

Objective(s): Iranian crack (IC) is a heroin-based substance manifesting various pathologic side effects. Herein, we aimed to investigate the mechanism of IC-induced liver injuries in Wistar rats. Materials and Methods: Twenty male Wistar rats were randomly divided into two groups: control, and IC (0.9 mg/kg/day/IP, for 30 days). Mitochondrial reactive oxygen species (ROS) production was measur...

A method for measuring three-dimensional (3-D) direction images of collagen fibers in biological tissue is presented. Images of the 3-D directions are derived from the measured transmission Mueller matrix images (MMIs), acquired at different incidence angles, by taking advantage of the form birefringence of the collagen fibers. The MMIs are decomposed using the recently developed differential d...

Two aldimine bonds have been shown to be present as stabilizing cross-links in intact collagen fibres from soft tissues: dehydrohydroxylysinonorleucine as a major component and dehydrolysinonorleucine being present in trace quantities. In the highly insoluble collagens less dehydrohydroxylysinonorleucine is present but the proportion of dehydrolysinonorleucine increases. In elastin the latter a...

Characterizing the collagen fiber orientation and organization in the eye is necessary for a complete understanding of ocular biomechanics. In this study, we assess the performance of polarized light microscopy to determine collagen fiber orientation of ocular tissues. Our results demonstrate that the method provides objective, accurate, repeatable and robust data on fiber orientation with µm-s...

To optimize the mechanical properties and integrity of tissue-engineered aortic heart valves, it is necessary to gain insight into the effects of mechanical stimuli on the mechanical behavior of the tissue using mathematical models. In this study, a finite-element (FE) model is presented to relate changes in collagen fiber content and orientation to the mechanical loading condition within the e...