Electron microscope and X-ray crystal analysis of the calcified elastic tissue

Abstract

Summary By means of electron microscope and X-ray powder method, the mineral phase of the calcified elastic tissue of human aortas was investigated. Its mineral group was found to be that of apatites. In the electron micrographs it appears as a sponge- like structure further resolvable in an aggregation of rod-like crystallites. Among these, the smallest ones are about 40 by 160 A. In some areas, the mutual orientation and meeting of the crystallites are so that they result in the formation of flakes, prisms and needle-like structures. From the X-ray crystal size determination, in fact, an average value of about 120 by 460 A was found. Moreover, in the electron micrographs no evident prevailing orientation of the crystallites, with respect to the organic substrate, was detectable as also revealed by the electron diffraction patterns where no arcing in 0.0.2 and 0.0.4 reflections can be seen.