scholarly journals ELECTRON MICROSCOPIC OBSERVATIONS OF THE CENTRAL NERVOUS SYSTEM

1956 ◽  
Vol 2 (5) ◽  
pp. 531-542 ◽  
Author(s):  
Sarah A. Luse
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Plasma Membrane ◽  
Longitudinal Section ◽  
Ependymal Cells ◽  
Proliferating Cells ◽  
Electron Microscopic ◽  
Granular Component ◽  
The Central Nervous System ◽  
Fibrous Astrocytes

In order to establish criteria for the identification of the neural and glial cells of the central nervous system, sections of the brains and spinal cords of mice, rabbits, guinea pigs, and rats; and portions of tumors of the human brain have been examined by electron microscopy. Identification of neurons is made possible by the characteristic cytoplasmic picture, in which there is a distinct granular and less constant membranous ergastoplasmic pattern. In no other cell of the central nervous system is such a distinct granular component present in the ergastoplasm. The shape of the neuron in electron microscopic preparations is similar to that seen by light microscopy with several dendrites containing a similar cytoplasm arising from the perikaryon. Synapses are relatively common on the surface of the neuron and its dendrites. Microglial cells are relatively small and dense with few processes, and are arranged as perineuronal and perivascular satellites for the most part. Occasionally phagocytized material is present in their cytoplasm. The oligodendroglial cells are identifiable by their position as perineuronal satellites and in the white matter as cells arranged in rows. They have a uniformly round to ovoid nucleus with a pale cytoplasm, which has a sparse, finely granular component and a few small mitochondria. The processes are few and relatively straight when cut in longitudinal section. The predominant cellular type in an oligodendroglioma was similar, with a pale cytoplasm. The astrocytes are variable in appearance. Their nuclei are moderately large, irregularly ovoid, and the cytoplasm adjacent to the nucleus is finely granular and scant. In the protoplasmic astrocytes the cytoplasm has a complicated infolded arrangement with reduplication of the plasma membrane, numerous processes extending radially from the cell and rebranching. To a certain extent this same folded plasma membrane was noted in the fibrous astrocytes. However, their more distant processes were narrowed, relatively straight, and filled with numerous dense fibrils. The processes of the astrocyte often surrounded axons, and other cellular processes, and surrounded some vessels, while attaching to a part of the wall of another vessel. Proliferating cells in experimentally produced gliosis and in astrocytic neoplasms were similar in structure. The ependymal cells and the epithelium of the choroid plexus have a specialized surface with microvillous projections of the cytoplasm covered by the plasma membrane. Cilia in varying numbers are present in both epithelia.

scholarly journals CHARACTERIZATION OF AN UNUSUAL CATECHOLAMINE-CONTAINING CELL TYPE IN THE TOAD HYPOTHALAMUS

1971 ◽  
Vol 48 (3) ◽  
pp. 650-672 ◽  
Author(s):  
Olivia C. McKenna ◽  
Jack Rosenbluth
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Chromaffin Cells ◽  
Cell Types ◽  
Ependymal Cells ◽  
Electron Microscopic ◽  
Large Numbers ◽  
The Central Nervous System ◽  
Cytological Characteristics

A nucleus of catecholamine-containing cells bordering the preoptic recess of the toad hypothalamus has been studied by both fluorescence histochemical and electron microscopic methods. The perikarya of these cells form one to three rows immediately subjacent to the ependyma. They send brightly fluorescent apical processes between the ependymal cells to the ventricular surface, and also give rise to long basal processes, the proximal portions of which are also fluorescent. These cells contain two distinctive constitutents: juxtanuclear bundles of tightly packed filaments, the members of which are separated from one another by only ∼100 A, and large numbers of dense-cored vesicles (400–2200 A in diameter), which appear to arise from an agranular tubular reticulum distinct from the Golgi apparatus. Axons containing either clear vesicles alone or clear and dense-cored vesicles form synapses on the subependymal cells, but no evidence has been found that the subependymal cells themselves form presynaptic contacts, or that axons originate from them. The cytological characteristics of these catecholamine-containing cells, plus the fact that they border directly on the cerebrospinal fluid, suggest that they may be more closely related to peripheral chromaffin cells than to the other cell types intrinsic to the central nervous system, and the name "encephalo-chromaffin cells" is therefore proposed for them. The possible functions of such cells in the central nervous system are discussed.

scholarly journals Reovirus Neurotropism and Virulence Are Dictated by Sequences in the Head Domain of the Viral Attachment Protein

2018 ◽  
Vol 92 (23) ◽  
Author(s):  
Danica M. Sutherland ◽  
Pavithra Aravamudhan ◽  
Melanie H. Dietrich ◽  
Thilo Stehle ◽  
Terence S. Dermody
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Ependymal Cells ◽  
Attachment Protein ◽  
Newborn Mice ◽  
Viral Attachment ◽  
Head Domain ◽  
Serotype 1 ◽  
The Central Nervous System ◽  
The Brain

ABSTRACTViral capsid components that bind cellular receptors mediate critical functions in viral tropism and disease pathogenesis. Mammalian orthoreoviruses (reoviruses) spread systemically in newborn mice to cause serotype-specific disease in the central nervous system (CNS). Serotype 1 (T1) reovirus infects ependymal cells to cause nonlethal hydrocephalus, whereas serotype 3 (T3) reovirus infects neurons to cause fulminant and lethal encephalitis. This serotype-dependent difference in tropism and concomitant disease is attributed to the σ1 viral attachment protein, which is composed of head, body, and tail domains. To identify σ1 sequences that contribute to tropism for specific cell types in the CNS, we engineered a panel of viruses expressing chimeric σ1 proteins in which discrete σ1 domains have been reciprocally exchanged. Parental and chimeric σ1 viruses were compared for replication, tropism, and disease induction following intracranial inoculation of newborn mice. Viruses expressing T1 σ1 head sequences infect the ependyma, produce relatively lower titers in the brain, and do not cause significant disease. In contrast, viruses expressing T3 σ1 head sequences efficiently infect neurons, replicate to relatively higher titers in the brain, and cause a lethal encephalitis. Additionally, T3 σ1 head-expressing viruses display enhanced infectivity of cultured primary cortical neurons compared with T1 σ1 head-expressing viruses. These results indicate that T3 σ1 head domain sequences promote infection of neurons, likely by interaction with a neuron-specific receptor, and dictate tropism in the CNS and induction of encephalitis.IMPORTANCEViral encephalitis is a serious and often life-threatening inflammation of the brain. Mammalian orthoreoviruses are promising oncolytic therapeutics for humans but establish virulent, serotype-dependent disease in the central nervous system (CNS) of many young mammals. Serotype 1 reoviruses infect ependymal cells and produce hydrocephalus, whereas serotype 3 reoviruses infect neurons and cause encephalitis. Reovirus neurotropism is hypothesized to be dictated by the filamentous σ1 viral attachment protein. However, it is not apparent how this protein mediates disease. We discovered that sequences forming the most virion-distal domain of T1 and T3 σ1 coordinate infection of either ependyma or neurons, respectively, leading to mutually exclusive patterns of tropism and disease in the CNS. These studies contribute new knowledge about how reoviruses target cells for infection in the brain and inform the rational design of improved oncolytic therapies to mitigate difficult-to-treat tumors of the CNS.

Toxoplasmosis of the central nervous system in the adult. Electron microscopic observations

1978 ◽  
Vol 41 (3) ◽  
pp. 211-216 ◽  
Author(s):  
H. C. Powell ◽  
C. J. Gibbs ◽  
A. M. Lorenzo ◽  
P. W. Lampert ◽  
D. C. Gajdusek
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Electron Microscopic ◽  
The Central Nervous System

Plasma-membrane calcium pumps and hereditary deafness

2007 ◽  
Vol 35 (5) ◽  
pp. 913-918 ◽  
Author(s):  
M. Brini ◽  
F. Di Leva ◽  
T. Domi ◽  
L. Fedrizzi ◽  
D. Lim ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Plasma Membrane ◽  
Alternative Splicing ◽  
Membrane Domains ◽  
Hereditary Deafness ◽  
Calcium Pumps ◽  
Specific Targeting ◽  
Alternatively Spliced ◽  
The Central Nervous System

In mammals, four different genes encode four PMCA (plasma-membrane Ca2+-ATPase) isoforms. PMCA1 and 4 are expressed ubiquitously, and PMCA2 and 3 are expressed predominantly in the central nervous system. More than 30 variants are generated by mechanisms of alternative splicing. The physiological meaning of the existence of so many isoforms is not clear, but evidently it must be related to the cell-specific demands of Ca2+ homoeostasis. Recent studies suggest that the alternatively spliced regions in PMCA are responsible for specific targeting to plasma membrane domains, and proteins that bind specifically to the pumps could contribute to further regulation of Ca2+ control. In addition, the combination of proteins obtained by alternative splicing occurring at two different sites could be responsible for different functional characteristics of the pumps.

Ewing's Family of Tumors Involving Structures Related to the Central Nervous System: A Review

2000 ◽  
Vol 3 (3) ◽  
pp. 203-210 ◽  
Author(s):  
M. Gary Hadfield ◽  
Martha M. Quezado ◽  
Robert L. Williams ◽  
Vivian Y. Luo
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Soft Tissues ◽  
Case Reports ◽  
Spinal Column ◽  
Diagnostic Methods ◽  
Electron Microscopic ◽  
Adjacent Structures ◽  
Microscopic Features ◽  
The Central Nervous System

This review consolidates information gleaned from several case reports and larger series on Ewing's sarcoma family of tumors (EFT) involving structures related to and found in the central nervous system (CNS). These tumors involve the skull, the spinal column, adjacent soft tissues, the meninges, and the brain. We have separated the cases by skull region and spinal column level, and we discuss the attendant differences in prognosis following treatment by neurosurgery, radiation, and chemotherapy. Light and electron microscopic features can be used to differentiate EFT from other small round blue cell tumors that involve the CNS (central primitive neuroectodermal tumor, lymphoma, etc.). Recent molecular and genetic findings in EFT provide new diagnostic methods. We conclude that EFT involving the CNS and adjacent structures is not so rare as previously stated and that the prognosis is more favorable, as a rule, than for the more common examples arising in the long bones and pelvis.

scholarly journals Tissue-specific expression of the heat shock protein HSP27 during Drosophila melanogaster development.

1990 ◽  
Vol 111 (3) ◽  
pp. 817-828 ◽  
Author(s):  
D Pauli ◽  
C H Tonka ◽  
A Tissieres ◽  
A P Arrigo
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Drosophila Melanogaster ◽  
Heat Shock ◽  
Stress Protein ◽  
Pupal Stage ◽  
Adult Brain ◽  
Proliferating Cells ◽  
Specific Expression ◽  
The Central Nervous System

The alpha-crystallin-related heat shock (stress) protein hsp27 is expressed in absence of heat shock during Drosophila melanogaster development. Here, we describe the tissue distribution of this protein using an immunoaffinity-purified antibody. In embryos, hsp27 translated from maternal RNA is uniformly distributed, except in the yolk. During the first, second, and early third larval stages, hsp27 expression is restricted to the brain and the gonads. These tissues are characterized by a high level of proliferating cells. In late third instar larvae and early pupae, in addition to the central nervous system and the gonads, all the imaginal discs synthesize hsp27. The disc expression seems restricted to the beginning of their differentiation since it disappears during the second half of the pupal stage: no more hsp27 is observed in the disc-derived adult organs. In adults, hsp27 is still present in some regions of the central nervous system, and is also expressed in the male and female germ lines where it accumulates in mature sperm and oocytes. The transcript and the protein accumulate in oocytes since the onset of vitellogenesis with a uniform distribution similar to that found in embryos. The adult germ lines transcribe hsp27 gene while no transcript is detected in the late pupal and adult brain. These results suggest multiple roles of hsp27 during Drosophila development which may be related to both the proliferative and differentiated states of the tissues.

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