PubMed HealthSearch

Biomedical subjects

E Morgenstern

Publications and source records attributed to E Morgenstern.

8 recordsLinked to original sources

The nucleated thrombocytoid cells. I. Electron microscopic studies on chicken blood cells.

By analyses of electron micrographs it was investigated whether nucleated thrombocytes of chickens described in the literature can be differentiated from lymphoid cells with sufficient certainty as an independent cell system. The result was negative. The mixture of lymphoid cells and so-called thrombocytes investigated was extremely polymorphous and, unlike mammalian platelets, proved to be one cell system containing younger and more mature cells. In the literature cells with signs of overmaturity or activation are designated as thrombocytes. Our studies suggest that a genuine thrombocyte system of chickens and other birds is not existent. The cell hitherto considered as nucleated thrombocytes seem to belong to the lymphoid system.

Animals

Disassembly of microtubules in the Lesch-Nyhan Syndrome? (Lesch-Nyhan syndrome and microtubules).

The Lesch-Nyhan syndrome is an unusual disease. It combines neurological disorders, behavioural disturbances, metabolic changes and haematological symptoms. The syndrome is caused by an X-chromosomal transmitted enzyme deficiency of the 'salvage pathway' in purine metabolism. The hitherto unexplained pathogenesis was the reason for investigations into metabolism and morphology of the blood cells of a patient suffering from the syndrome. Along with the defect in guanine nucleotide resynthesis there was a defect of microtubules in platelets and a sphaerocytosis in red cells, which could be the result of a disassembly of structural proteins. The development and maintenance of the highly heteromorphic structure of nerve cells and the neuronal function including axonal transport of cell organelles and transmitters is dependent on microtubules. Thus a disassembly of microtubules could be the mechanism in the pathogenesis of this complex syndrome.

Adenine Phosphoribosyltransferase

[Cytochemical studies of ultrathin frozen sections of blood platelets].

Results obtained by conventional techniques and freeze-ultramicrotomie have been compared. Ultrathin frozen sections of platelets, which are fixed by glutaraldehyde, freeze-protected by polyvinyl-pyrrolidone and encapsulated in gelatin show a well preserved fine structure after staining with buffered OsO4, phosphotungstic, phosphomolybdic or ammoniummolybdic acid. The preservation of polysaccharides or mucopolysaccharides depends on a suitable fixation, that of glycogen in certain cases depends on a double fixation (glutaraldehyde and OsO4). Cytoplasmic nucleoproteins like ribosomes are visible only after drying of sections and staining with uranyl-acetate. Lipids, both membrane lipoproteins as well as lipids in the matrices of cell organelles, are well preserved. For example the zinc-iodide osmiumtetroxide reaction yields positive results in frozen sections contrary to such obtained by conventional methods. Furthermore, the extraction of altered lipids after staining with dyes like acridine orange does not take place with this method. For this reasons the freeze-ultramicrotomy seems to be an useful alternative method.

Animals