Atherosclerotic plaque: x-ray diffraction investigation.

Human atherosclerotic plaque material continuotusly maintained in an aqueous environment has been subjected to examination by x-ray diffraction. The first diffraction pattern from single crystals of human biological apatite was obtained from the plaque material of a freshly excised plaque when it was equilibrated with its aqueous environment. As the plaque material dried, the discrete spots characteristic of single crystal diffraction disappeared, leaving only the powder pattern of apatite.