CALCIFICATION IN THE CARDIOVASCULAR SYSTEM

总体目标是开发关于运动的足够信息， 心血管钙化的热力学和结构性质 存款使这方面的预防和治疗成为可能 病理学。有强有力的证据表明钙化是通过 酸性磷酸钙(含HPO4)前驱体的形成 其速率可以通过生理上可接受的抑制剂来降低。 具体目标： I.钙化改进剂，包括锌离子、镁离子、锶离子和磷74-离子， 将根据他们改变利率的相对能力进行评估 钙化。 II.钙化机制的适用性将通过以下方式进行测试 牛心包种植体钙化的进展 大鼠~(32)P热解技术及其钙磷比的测定 押金。 来自心血管系统不同部位的存款将被 分析以确定是否有相似之处表明 间接地，一种控制它们形成的共同机制。 四、对直接投资获得的产品进行比较 与前驱钙化机制的对比；其中一个方面是 确定导致化学计量比形成的条件 羟基磷灰石。 五、已发现生物磷灰石前驱体的组成和结构 将通过使用化学物质来确定心血管沉积物中的 分析、IR、X-射线粉末衍射和单晶分析。 六.在#年发现的碳酸盐的另一种结合机制 将对心血管存款进行调查。需要检验的一个假设是 其中一种前体可以将碳酸盐结合到它的结构中 形成一种盐，在生理条件下会水解成碳酸盐磷灰石 条件。元素分析、X射线衍射、拉曼光谱和红外光谱将用于 描述这些化合物的特征。 Vii.白锁石溶解度的测定，即 在其他生物组织中偶尔发现的Ca18Mg2H2(PO4)14将有所帮助 确定它是否可能是钙化心血管的一个组成部分 含有镁离子的沉积物。 八.引起内在(表层下)钙化的机制 将对组织衍生植入物进行研究。结果将会是 表征种植体组织和组织的渗透选择膜特性 确定生理离子在组织中的扩散特征。 当代试验设计和分析的统计方法 将使用数据。

The overall objective is to develop sufficient information on the kinetic, thermodynamic, and structural properties of cardiovascular calcific deposits to make possible prevention and cure of this aspect of the pathology. There is strong evidence that the calcification occurs by way of acidic calcium phosphate (containing HPO4) precursors, the formation rates of which can be reduced by physiologically acceptable inhibitors. Specific aims: I. Calcification modifiers, including Zn2+, Mg2+, Sr2+, and P2O74- ions, will be evaluated for their comparative abilities to alter rates of calcification. II. The applicability of the calcification mechanism will be tested by following the progression of bovine pericardium implant calcification in rats using a 32P-pyrolysis technique and Ca/P ratio measurements of the deposits. III. Deposits from different sites of the cardiovascular system will be analyzed to determine whether there are similarities that would indicate indirectly a common mechanism that controls their formation. IV. A comparison will be made of the products obtained by the direct versus the precursor calcification mechanism; one aspect of this is to determine conditions that lead to the formation of stoichiometric hydroxyapatite. V. The compositions and structures of the precursors of bioapatites found in cardiovascular deposits will be determined with the use of chemical analysis, IR, X-ray powder diffraction, and single-crystal analysis. VI. An alternative mechanism for the incorporation of carbonate found in cardiovascular deposits will be investigated. A hypothesis to be tested is that one of the precursors can incorporate carbonate into its structure to form a salt that will hydrolyze to carbonate apatite under physiological conditions. Elemental analyses, XRD, Raman and IR will be used to characterize the compounds. VII. A determination of the solubility of whitlockite, which is Ca18Mg2H2(PO4)14, occasionally found in other biological tissues, will help determine whether it could be a component of calcified cardiovascular deposits, which contain Mg ions. VIII. Mechanisms that cause intrinsic (subsurface) calcification of tissue-derived implants will be investigated. The results will characterize the permselective membrane properties of implant tissues and determine the diffusion features of physiological ions into the tissues. Contemporary experimental designs and statistical methods for analyzing data will be used.