CHARACTERIZATION OF INORGANIC BONE MINERAL PHASES

无机骨矿物相的表征

• 批准号: 3456925
• 负责人: DOSUK D LEE
• 金额: $ 10.12万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-07-01 至 1991-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3456925
• 关键词: calcium phosphate; chickens; computer graphics /printing; electron microscopy; laboratory rat; normal ossification; osteomalacia; vitamin D deficiency

The proposed study will identify the microchemical composition of the initial and subsequent mineral phases in sections of normal and vitamin Ddeficient osteomalacic bone tissues. in addition, to determine the temporal relationship, this study will use high voltage electron stereomicroscopy together with computer graphic reconstructions to obtain threedimensional locations of the minerals in respect to the tissue ultrastructure. While the presence of hydroxyapatite has been well established, the same is not true for secondary calcium phosphate mineral phases with lower calcium/phosphate ratios, such as brushite, octacalcium phosphatem, and tricalcium phosphate (which exist in some pathologicallyrelated calcification in teeth). No investigation has yet been reported on diseased bone tissues involving inadequate mineralizaiton resulting from deficient calcium and/or phosphate levels. These secondary calcium phosphate phases inherit higher solubility and dissolution rate than the hydroxypatite phase. Therefore, determining the presence of these phases in metabolic bone diseases, such as osteomalacia, or other diseases involving insufficient amount of minerals in osteoid, is critical in not only understanding the physicochemistry of mineral formation in bone but also to developing concepts and potential solutions to bone tissue pathologies. In order to eliminate chemical fixation and staining, we will employ the ultracryomicrotomy method for specimen preparation. To maximize instrumental sensitivity for the detection of small amounts of inorganic constitutents, high voltage electron microdiffraction techniques will be adapted. The high voltage electron microscope is equipped with an environmental chamber that allows the examination of the tissue in their natural state, in their unfrozen hydrated condition. In addition, high voltage stereomicroscopy and threedimensional computer reconstruction will be used to obtain the structural information, and thus, spatial and temporal sequence will be determined. These are the most uptodate methods for obtaining the most complete and intimate knowledge of the inorganic constituents of bone tissue heretofore obtained.

拟议的研究将确定微量化学成分 初始和后续矿物阶段的正常剖面 和维生素D缺乏的骨软化骨组织。 此外，本发明还涉及一种用于该方法， 为了确定时间关系，本研究将使用高 电压电子体视显微镜与计算机联用 图像重建以获得 组织超微结构方面的矿物质。 虽然羟基磷灰石的存在已经得到很好的证实， 对于二次磷酸钙矿物质，情况并非如此 具有较低钙/磷酸盐比的相，例如透钙磷石， 磷酸八钙和磷酸三钙（存在于 牙齿中某些病理相关钙化）。 没有 对患病骨组织的研究尚未有报道 由于缺乏足够的矿物质 钙和/或磷酸盐水平。 这些二级磷酸钙相继承了较高的 溶解度和溶解速率比羟基磷灰石相。 因此，确定代谢中这些相的存在， 骨疾病，如骨软化症，或其他涉及 类骨质中矿物质含量不足，不仅 了解骨骼中矿物质形成的物理化学 同时也是为了发展骨骼的概念和潜在的解决方案， 组织病理学 为了消除化学固定和染色，我们将 采用冷冻切片法制备标本。 为了最大限度地提高仪器的灵敏度， 无机物含量，高压电子 将采用微衍射技术。 高压 电子显微镜配备有环境室 允许检查自然状态下的组织， 它们解冻后的含水状态 此外，高电压 体视显微镜和三维计算机重建 将被用来获得结构信息，因此，空间 并将确定时间顺序。 这些是最 最新的方法来获得最完整和最亲密的 迄今为止，对骨组织无机成分的认识 得到了