Role of Microstructure in Nanomechanical Behavior of Bone Tissue

微结构在骨组织纳米力学行为中的作用

• 批准号: 7643348
• 负责人: Marjolein C van der Meulen
• 金额: $ 31.46万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2011-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7643348
• 关键词: Affect; Behavior; Bone Density; Bone Matrix; Bone Tissue; Collagen; Data; Disease; Dose; Elastic Tissue; Failure; Femur; Fluorides; Fracture; Generations; Goals; Hardness; Heterogeneity; Human; Length; Link; Measurement; Measures; Mechanics; Metabolic acidosis; Microscopy; Minerals; Modeling; Osteoporosis; Performance; Pre-Clinical Model; Property; Rattus; Research Personnel; Role; Science; Sheep; Skeleton; Solid; Specimen; Spectroscopy, Fourier Transform Infrared; Stress; Structure; Techniques; Testing; Time; Tissues; Translating; Vertebral Bone; Vitamin D Deficiency; Weight-Bearing state; base; bisphosphonate; bone; bone geometry; bone mass; bone strength; density; effective therapy; infrared microscopy; lumbar vertebra bone structure; mechanical behavior; mineralization; multi-scale modeling; nanoindentation; nanomechanical; programs; second harmonic; skeletal; submicron

DESCRIPTION (provided by applicant): The role of tissue microstructure in the tissue mechanical properties is important to understanding the determinants of skeletal integrity. The goal of this proposal is to correlate bone tissue composition with tissue mechanical properties for treatments that result in well-established alterations in bone matrix composition and altered whole bone strength to test the following hypotheses: Hypothesis 1: Reduced bone mineral density or increased mineral crystal size reduces tissue elastic modulus and hardness. Specific Aim 1a: Mineral content will be reduced by 3 and 4 weeks of vitamin D-deficiency in growing rats. The treatment will be confirmed with whole bone bending tests. Tissue elastic modulus, composition and microstructure will be characterized. Tissue composition and microstructure will be correlated with indentation moduli and hardness in the femur and lumbar vertebra. Specific Aim 1b: Altered mineralization will be produced by 3 and 4 weeks of fluoride treatment of growing rats to weaken whole bone structure and alter mineral crystal size. Tissue properties will be analyzed and correlated as in Specific Aim 1 a. Hypothesis 2: Metabolic acidosis produces matrix changes that reduce tissue elastic modulus. Specific Aim 2: Metabolic acidosis in sheep is a preclinical model of human osteoporosis that reduces bone mass and alters tissue mineralization. The tissue properties will be analyzed and correlated in this sheep model as in Specific Aim 1. Additionally, bulk properties will be determined for specimens from the cortex. Models incorporating microstructural detail will be used to relate the behavior across length scales. Hypothesis 3: Bisphosphonate treatment increases tissue elastic modulus and hardness. Specific Aim 3: Bisphosphonate treatment will be used to overcome osteoporosis following metabolic acidosis from Specific Aim 2. Tissue and bulk properties will be analyzed and correlated as in Specific Aim 2. We will relate composition and microstructure of bone tissue to the elastic behavior, focusing on the role of mineral and collagen content, crystal size and collagen alignment. Our approach will cross-correlate several microlevel techniques that have not been previously used to characterize bone tissue mechanics.

描述（由申请人提供）：组织微观结构在组织机械性能中的作用对于理解骨骼完整性的决定因素很重要。该提案的目的是将骨骼组织组成与组织机械性能相关联，用于治疗，从而导致骨基质组成的良好变化并改变了整个骨骼强度以检验以下假设：假设1：骨矿物质密度降低或矿物质尺寸的降低可减少组织弹性模块和硬度。特定的目标1A：矿物质含量将减少3周和4周的生长大鼠维生素D缺乏症。将通过全骨弯曲测试来确认治疗。将表征组织弹性模量，组成和微观结构。组织组成和微观结构将与股骨和腰椎的压痕模量和硬度相关。特定的目标1B：矿化的改变将由生长大鼠的氟化物处理3和4周产生，以削弱整个骨骼结构并改变矿物质晶体尺寸。组织特性将被分析和相关，如特定目标1 a所示。假设2：代谢性酸中毒会产生基质变化，以减少组织弹性模量。具体目标2：绵羊中的代谢性酸中毒是人类骨质疏松症的临床前模型，可减少骨骼质量并改变组织矿化。在该绵羊模型中，将分析和相关组织的组织特性，如在特定目标1中。此外，将确定来自皮质样本的散装特性。结合微观结构细节的模型将用于将长度尺度的行为联系起来。假设3：双膦酸盐处理增加了组织弹性模量和硬度。特定目的3：将双膦酸盐治疗从特定目标2中进行克服骨质疏松症。2。将分析和相关性和相关性与特定目标2一样。我们将将骨组织的组成和微观结构与弹性行为相关联，集中在矿物质和胶原蛋白含量和胶原蛋白含量和胶原蛋白的作用上，晶体尺寸和浓collagen，crystal and crystal，crystal，crystal alignment，crystal Alignment。我们的方法将跨色的几种微观技术，这些技术以前尚未用于表征骨组织力学。