BIOTRIBOLOGY OF DIARTHRODIAL JOINTS

关节生物摩擦学

• 批准号: 6375016
• 负责人: GERARD A. ATESHIAN
• 金额: $ 19.7万
• 依托单位: COLUMBIA UNIV NEW YORK MORNINGSIDE
• 依托单位国家: 美国
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-06-15 至 2004-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6375016
• 关键词: articular cartilage; biomechanics; joints; mechanical pressure; mechanical stress; protein degradation; surface property; synovial fluid; tissue /cell culture

DESCRIPTION (adapted from the Investigator's abstract): This is a first renewal application of an excellent, highly productive team of a Bioengineer (G. Ateshian) with a Biochemist (W. Valhmu) who are studying the mechanisms of articular cartilage lubrication and/or failure of lubrication on loading/frictional characteristics of bovine articular cartilage. Based on previous theories and experiments, the authors propose new experiments to further characterize the relationships between friction and fluid pressurization of articular cartilage. The overall theory being tested is that pressurization shifts load away from contacting cartilage surfaces, thus decreasing friction until pressurization subsides. Three relevant hypotheses are to be tested in this renewal: 1/that friction depends on interstitial fluid support load, equilibrium frictional coefficient and solid-to-solid contact; that cartilage-on-cartilage contact fraction area is smaller than cartilage on glass. 2/ under normal loading, cartilage always maintains high interstitial fluid support with low friction and 3/ enzymatic degradation will defeat interstitial load mechanisms and increase the coefficient of friction. Using a unique load-or-displacement controlled frictional testing apparatus containing a microchip pressure transducer to measure cartilage interstitial fluid pressurization directly, the authors will systematically test these hypotheses through a series of carefully thought out permutations and combinations of load-versus-displacement controlled tests. The ability to test the fluid pressures within cartilage samples under these various, well-controlled, physiologically relevant loading conditions, in order to test various theories of cartilage lubrication and friction, is extremely important and unique. The investigators provide extensive evidence that this proposal is both logical and feasible. Their background review on the topic, along with their papers on the topic over the past few years are all outstanding. They provide both strong theoretical and experimental evidence to support the concepts that they are testing. The main concept is that fluid pressurization is critical to controlling cartilage friction. They will test that theory using cartilage-on-glass tests along with some very important and unique cartilage-on-cartilage tests at stresses from 0.05Mpa-5 Mpa, frequencies of 0.0005Hz - 0.5 Hz and up to 10 percent compressive strains, with and without enzymatic (collagenase, chondroitinase ABC and hyaluronidase) treatments.

描述(改编自调查者摘要)：这是第一次更新 应用一支优秀的、高生产率的生物工程师团队(G. Ateshian)和一位生物化学家(W.Valhmo)，他们正在研究 关节软骨润滑和/或润滑失效 牛关节软骨的载荷/摩擦特性。基于 以前的理论和实验，作者提出了新的实验来 进一步描述摩擦力和流体之间的关系 关节软骨加压。正在测试的总体理论是 加压将负荷从接触软骨表面转移，因此 减少摩擦力，直到加压作用减弱。三个相关假设 将在这次更新中得到检验：1/摩擦力取决于间质流体 支承载荷、平衡摩擦系数和固-固接触； 软骨-软骨接触分数面积小于软骨-软骨接触面积。 玻璃杯。2/在正常负荷下，软骨始终保持高间质 低摩擦和3/酶降解的流体支撑体将失败 间隙载荷机制和增加摩擦系数。使用 独特的载荷或位移控制摩擦测试仪器，包含 一种测量软骨间质液的微芯片压力传感器 直接加压，作者将系统地检验这些假说 通过一系列仔细考虑的排列和组合 载荷-位移控制试验。测试液体的能力 软骨样本内的压力在这些不同的、控制良好的 生理相关的载荷条件，以检验各种理论 软骨的润滑和摩擦，是极其重要和独特的。这个 调查人员提供了大量证据，证明这一提议既合乎逻辑，又 可行。他们对这一主题的背景回顾，以及他们关于 这几年的话题都很突出。它们既提供了强大的 理论和实验证据支持它们是 测试。主要的概念是流体增压对 控制软骨摩擦。他们将用来测试这个理论 玻璃上的软骨测试以及一些非常重要和独特的 在0.05 Mpa-5 Mpa的应力下进行软骨对软骨的测试，频率 0.0005赫兹-0.5赫兹和高达10%的压缩应变，有无应变 酶(胶原酶、软骨素酶ABC和透明质酸酶)处理。