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Biomedical subjects

J M Valigorsky

Publications and source records attributed to J M Valigorsky.

5 recordsLinked to original sources
PubMed1976

Aging changes in the human aortic valve in relation to dystrophic calcification.

To elucidate the pathogenesis of aging changes and their relation to age associated calcification, a morphological study of 27 human aortic valves was carried out. Nine valves were obtained from immediate autopsies and 18 valves from routine autopsies done within four hours after death. Calcium deposition was present deep in the zona fibrosa along a zone of lipid accumulation. Fibrocytes in the zona fibrosa showed predominant age associated changes, i.e., a massive accumulation of residual bodies in the cytoplasm probably derived from autophagic vacuoles. Light microscopic lipid accumulation corresponded with both intracellular accumulation of electron dense spherules and membranous vesicles derived from degenerate fibrocytes. Calcium deposition in various stages, including needle shaped hydroxyapatite crystals, was seen in close association with these cellular degradation products rather than collagen or elastic fibers. Dystrophic calcification in the aortic valve appears to result from cellular aging and death followed by petrification of cellular degradation products, which may progress to calcific aortic stenosis.

Adolescent↗
PubMed1975

The application of electron microscopy and cellular biochemistry to the autopsy. Observations on cellular changes in human shock.

A method based on the utilization of electron microscopy, morphometric analysis, tissue culture, and biochemical analysis in the study of human autopsies is described. In this method rapid sampling immediately following somatic death is conducted in order to make meaningful the application of such techniques. In addition to describing the procedure, we present some new findings relating to cellular changes associated with shock. As in cellular pathobiology, it is of utmost importance that ultrastructural changes be correlated with alterations in chemistry and function.

Adolescent↗
PubMed1975

Effects of shock on the pancreatic acinar cell. Cellular and subcellular effects in humans.

Pancreatic tissues from 22 patients with a wide variety of types of shock were obtained within minutes of somatic death for light and electron microscopy and for cytochemical studies. By light microscopy, it was difficult to ascertain any differences between the shock groups; however, electron microscopy disclosed subcellular alterations that could be correlated well with the type, severity, and duration of shock. Mild cases of shock or shock of short duration showed mild cell damage, while extreme cases of hemorrhagic or septic shock showed cell death and necrosis. No morphological evidence for lysosomal initiation of damage was seen, but it is clear that the pancreas can undergo severe cell injury during shock that could result in release of further damaging enzymes, most probably from zymogen granules rather than from lysosomes.

Adolescent↗