Tissues mechanical properties

At this point, it is worth noting that there is limited data regarding the actual local mechanical properties of native and diseased tissues. Rather, our knowledge of tissue mechanical properties is largely based on macroscopic mechanical measurements. The lack of mechanical property characterization at the microscale... 

Form and function target tissue mechanical properties and device function as inputs for tailoring the polymer mechanical properties... 

Nonlinear ionic channels conductance, 28-8 Nonmineralized human tissues, mechanical properties,... 

Yerramshetty, J.S., Lind, C., and Akkus, O. (2006) The compositional and physicochemical homogeneity of male femoral cortex increases after the sixth decade. Bone, 39 (6), 1236-1243. Donnelly, E. et al. (2010) Effects of tissue age on bone tissue material composition and nanomechanical properties in the rat cortex. J. Biomed. Mater. Res. A, 92 (3), 1048-1056. Donnelly, E. et al (2010) Contribution of mineral to bone structural behavior and tissue mechanical properties. Calcif. Tissue Int., 87 (5), 450—460. Pathak, S. et al (2012) Assessment of lamellar level properties in mouse bone utilizing a novel spherical nanoindentation data analysis method. J. Mech. Behav. Biomed. Mater., 13, 102—117. Burket, J.C. et al (2013) Variations in nanomechanical properties and tissue composition within trabeculae from an ovine model of osteoporosis and treatment. Bone, 52 (1), 326-336. Carden, A. et al (2003) Ultrastructural changes accompanying the mechanical deformation of bone tissue a Raman imaging study. Calcif. Tissue Int., 72 (2), 166-175. 

The first synthetic polyglycoHc acid suture was introduced in 1970 with great success (21). This is because synthetic polymers are preferable to natural polymers since greater control over uniformity and mechanical properties are obtainable. The foreign body response to synthetic polymer absorption generally is quite predictable whereas catgut absorption is variable and usually produces a more intense inflammatory reaction (22). This greater tissue compatibihty is cmcial when the implant must serve as an inert, mechanical device prior to bioresorption. 

Resilient Diners. Resilient liners reduce the impact of the hard denture bases on soft oral tissues. They are designed to absorb some of the energy produced by masticatory forces that would otherwise be transmitted through the denture to the soft basal tissue. The liners should adhere to but not impair the denture base. Other critical properties include total recovery from deformation, retention of mechanical properties, good wettability, minimal absorption of... 

Materials used in body implants must meet several essential requirements such as tissue compatibility, enzymatic and hydrolytic stability. They must also be chemically resistant and have good mechanical properties. They must not be toxic, or the surrounding tissue will die. They must be resistant to the body fluids which usually have a high percentage of chloride ions. They must be biologically active if an interfacial bond is to be achieved. In some cases, they must be able to withstand continued high mechanical stresses for many years. 

The PGS obtained by Wang and coworkers was a kind of thermoset elastomer with the Young s modulus of 0.282 0.025 MPa, a tensile strain of at least 267 zE 59.4%, and a tensUe strength was at least 0.5 MPa. The mechanical properties of PGS were well consisted with that of some common soft tissues. Although PGS is a thermoset polymer, its prepolymer can be processed into various shapes by solving it in common organic solvents such as 1,3-dioxolane, tetrahydrofuran, isopropanol, ethanol, and iV,M-dimethylformamide. Porous scaffolds can be fabricated by salt leaching. 

Another example was done by Opitz et al. They utilized P4HB scaffolds to produce viable ovine blood vessels, and then implanted the blood vessels in the systemic circulation of sheep. Enzymatically derived vascular smooth muscle cells (vSMC) were seeded on the scaffolds both under pulsatile flow and static conditions. Mechanical properties of bioreactor-cultured blood vessels which were obtained from tissue engineering approached those of native aorta. 

Furthermore, our results on the characterization of the physico-mechanical properties of tyrosine-derived poly(iminocarbonates) provide preliminary evidence for the soundness of the underlying experimental rationale The incorporation of tyrosine into the backbone of poly(iminocarbonates) did indeed result in the formation of mechanically strong yet apparently tissue-compatible polymers. 

Multiple applications for resilin-like polypeptides have garnered renewed research interest since the report of the first recombinant resilin in 2005. The excellent mechanical properties of the resilin-like polypeptides has directed investigation toward their use as high-performance materials and in tissue engineering applications. It is widely acknowledged that cells interact and take cues from their microenvironment and, therefore, the development of polymeric scaffolds to mimic the extracellular matrix and drive desired cell or tissue responses has been of wide interest. To this end, our laboratories have developed a modular resilin-like polypeptide (RLP12) (see Fig. 20) that contains not only twelve repeats of the... 

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