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M R Issidorides

Publications and source records attributed to M R Issidorides.

26 records · Page 2Linked to original sources
PubMed1978

Protein-rich cytoplasmic bodies of substantia nigra and locus ceruleus. A comparative study in parkinsonian and normal brain.

A histochemical study of substantia nigra and locus ceruleus from postmortem brains showed the presence of small spherical cytoplasmic bodies stained selectively by the anionic phosphotungstic acid-hematoxylin (PTAH) stain at a pH of 2.5. The metachromatic reaction to PTAH indicates that these protein bodies contain a protein rich in free basic amino groups. The protein bodies are localized within the neuronal perikaryon as well as in their dendritic processes. These bodies abundantly present in the substantia nigra and locus ceruleus of normal brains were noticeably reduced or absent in parkinsonian brains. Lewy bodies when present show that their core gives the same metachromatic reaction to PTAH as do the protein bodies. These findings suggest that an abnormality of protein synthesis in the substantia nigra and locus ceruleus of parkinsonian brains may be related to the absence of protein bodies and the formation of Lewy bodies and play a role in pathogenesis of the parkinsonian state.

Aged↗
PubMed1976

Histochemical changes in the blood cells of schizophrenic patients under pimozide treatment.

Chromatin structure and nucleohistone pattern were investigated histochemically in the neutrophils of 11 schizophrenics and 16 healthy controls. Compared to controls, all schizophrenic parents prior to medication showed a distinctly different histochemical pattern consisting of increased concentration and abnormal distribution of nucleohistones. This pattern has been attributed to an increase of arginine-rich histones in schizophrenics. Pimozide administration exerted a normalizing effect on the nucleohistone distribution pattern. These findings further support our view that genomic expression abnormalities may be related to schizophrenic illness.

Adolescent↗
PubMedDate not supplied

Ultrastructural identification of protein bodies, cellular markers of human catecholamine neurons, in a temporal lobe ganglioglioma.

A temporal lobe ganglioglioma, surgically removed from an 8-year-old body, and a human brainstem at the level of locus coeruleus (LC) were processed for light microscopy (LM), with formalin fixation and paraffin embedding, and for electron microscopy (EM) with glutaraldehyde fixation, potassium permanganate postfixation, phosphotungstic acid-hematoxylin block-staining, and epoxy resin embedding. The paraffin sections were stained with toluidine blue O/rhodamine B and observed under epi-fluorescence. The thin sections for EM were viewed directly without further staining. The neuronal neoplastic cells of ganglioglioma and the neurons of LC are known to produce catecholamines. Both also contain spherical protein bodies (pb), cellular markers that identify catecholamine neurons in humans. The ultrastructural characteristics of the pb in LC were compared with those of the pb in neoplastic ganglion cells. These bodies had an identical ultrastructure, in both tissues, consisting of electron-lucent core surrounded by an electron-dense thin rim. The rhodamine B-stained sections also emphasized the identical morphology of the pb in ganglioglioma and LC. Based on the EM comparison, these brightly fluorescing spherical bodies are ideal markers for identifying in LM, the clusters of large neoplastic cells, representing neurons, which are the most important clue to the correct diagnosis of gangliogliomas.

Biomarkers↗