CHARACTERIZATION OF INORGANIC BONE MINERAL PHASES

无机骨矿物相的表征

• 批准号: 3456924
• 负责人: DOSUK D LEE
• 金额: $ 11.22万
• 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/3456924
• 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化学组成 正常部分的初始和后续矿物相 和维生素dDECOINIGINE的成骨骨组织。 此外， 为了确定时间关系，本研究将使用高 电压电子显微镜与计算机一起 图形重建以获得三二维位置 关于组织超微结构的矿物质。 虽然羟基磷灰石的存在已得到充分确立，但 磷酸二钙矿物质的情况并非如此 具有较低钙/磷酸盐比的相位，例如刷子， 八钙磷脂和磷酸三钙（存在于 牙齿中的一些病理相关钙化）。 不 尚未报告患病的骨骼组织 涉及由于不足而导致的矿物质不足 钙和/或磷酸盐水平。 这些继发磷酸钙相继承了更高的 溶解度和溶解速率比羟基矿相。 因此，确定这些阶段在代谢中的存在 骨骼疾病，例如骨瘤或其他涉及的疾病 骨质骨质中的矿物质不足，不仅在 了解骨骼中矿物形成的物理化学 而且还要开发骨骼的概念和潜在解决方案 组织病理。 为了消除化学固定和染色，我们将 采用超细胞切开术方法进行标本制备。 为了最大程度地提高仪器灵敏度以检测小 无机组成部分，高压电子 微屈光技术将进行调整。 高压 电子显微镜配备了环境室 这允许检查组织以其自然状态，在 他们的水合条件未结合。 另外，高压 立体显微镜和三维计算机重建 将用于获取结构信息，因此将 并确定时间序列。 这些是最大的 上调方法，以获得最完整，最亲密的方法 迄今为止骨组织的无机成分的知识 获得。