The mineral component of human cardiovascular deposits: morphological, structural and crystal‐chemical characterization

Abstract

Complementary experimental techniques were applied to characterize bioapatite nanocrystals from pathological cardiovascular deposits. The investigated collection included the leaflets from aortic valve, leaflets from mitral valve, leaflets from tricuspid valve and calcified aorta's wall. XRD, EDX and FTIR data have shown that all studied samples consist of imperfect apatite with different crystallinity and variable chemical composition. In accordance with TEM data, the crystals of pathological calcified deposits frequently have oblong or rod‐like shape (length of 60‐90 nanometers, width of 20‐30 nanometers). At the same time, in the SEM and TEM experiments, the complex spheroid assemblies and planar sheet‐like shaped formations with crystal structure close to apatite were observed. Probably, the different shape and morphology of the particles are caused by different ways of crystal nucleation and growth, although the exact mechanisms remain an open question.

Step down Vascular Calcification Analysis using State-of-the-Art Nanoanalysis Techniques

“…The variance in the EDX-results on the trabecular bone sample is somewhat higher, showing Ca/P-ratios varying with sample location between 1.4 and slightly above 1.6, which is close to that of ideal hydroxylapatite (Ca/P-ratio = 1.67). A Ca/P-ratio below 1.5 is indicative of non-apatitic structure 17 18 . Inconsistencies in the quantitative results are most likely to be due to material inhomogeneity.…”

Composition and morphological characteristics of sialoliths

“…In more detail, apart from the characteristic ν 3 band at 1035 cm −1 , peaks attributed to other PO vibrational modes of the phosphate group appear at 601 cm −1 and 561 cm −1 . The bands at 1457 cm −1 and 1419 cm −1 arise from vibrations due to the presence of carbonate ions and along with the at 874 cm −1 band are characteristic for biological apatites .…”

“…Carbonate ions are the most common substitutions and they can replace either hydroxyl or phosphate lattice sites; often reffered to as A‐ and B‐type substitutions. It is well known that the presence of carbonates in the HAP structure is quite common in biological apatites , having a profound effect on their physicochemical properties. More specifically, crystallinity decreases with the increase of carbonate content.…”

Papillary thyroid carcinoma with biomineralization: clinical and morphological features

“…Співвідношення Са та Р у капсулі пухлинного вузла й ПТ при ПРЩЗ відповідає мінералу гідроксиапатиту. Присутність гідроксиапатиту є характерною також для інших локалізацій патологічних процесів із проявами дистрофічної кальцифікації, що показано у наших попередніх роботах [12][13][14].…”