Reorganization of the Somatosensory Cerebral CortexAfter Peripheral Damage

Physiology ◽  
1986 ◽  
Vol 1 (1) ◽  
pp. 15-19
Author(s):  
R Verley

If a sensory nerve is sectioned, it is expected that the centrally deprived projection area should be reduced to silence and atrophy. However, in recent years the capacity of the central nervous system for reorganization has received increasing attention. This article concerns elimination of input from the tactile system on the head of rodents, which has two components, the long vibrissae and the common fur. After early destruction of the vibrissae in newborn rats, the deprived cortex unexpectedly was not significantly reduced because substitution occurred. If only the vibrissae were destroyed, small fur hairs substituted for them. If both vibrissae and small hairs on the muzzle were destroyed, fur hairs of other head regions took over. This shows that early deprivation leads to reorganization in the somatosensory cortex that reveals greater than expected plasticity. Thus the principle of specificity of neural connections, a basic principle of neurology, must be reappraised.

Author(s):  
Ezzatollah Keyhani

Acetylcholinesterase (EC 3.1.1.7) (ACHE) has been localized at cholinergic junctions both in the central nervous system and at the periphery and it functions in neurotransmission. ACHE was also found in other tissues without involvement in neurotransmission, but exhibiting the common property of transporting water and ions. This communication describes intracellular ACHE in mammalian bone marrow and its secretion into the extracellular medium.


1973 ◽  
Vol 71 (1-2) ◽  
pp. 1-8 ◽  
Author(s):  
Sylvio Celso Goncalves da Costa ◽  
Samuel B. Pessoa ◽  
Neize de Moura Pereira ◽  
Tania Colombo

The main object of the present paper is to furnish a brief account to the knowledgement of Protozoa parasitic in common Brazilian frog of the genus Leptodactylus for general students in Zoology and for investigators that use this frog as a laboratory animal. Hepatozoon leptodactyli (Haemogregarina leptodactyli) was found in two species of frogs - Leptodactylus ocellatus and L. pentadactylus - in which develop schizogony whereas sporogony occurs in the leech Haementeria lutzi as was obtainded in experimental conditions. Intracellular forms have been found in peripheral circulation, chiefly in erythrocytes, but we have found them in leukocytes too. Tissue stages were found in frog, liver, lungs, spleen, gut, brain and heart. The occurence of hemogregarine in the Central Nervous System was recorded by Costa & al,(13) and Ball (2). Some cytochemical methods were employed in attempt to differentiate gametocytes from trophozoites in the peripheral blood and to characterize the cystic membrane as well. The speorogonic cycle was developed in only one specie of leech. A brief description of the parasite is given.


1990 ◽  
Vol 123 (1) ◽  
pp. 100-107
Author(s):  
L. Goya ◽  
C. Aláez ◽  
A. M. Pascual-Leone

Abstract. The development of epinephrine, norephinephrine, and total catecholamine secretion in plasma and andrenal glands was studied in newborn rats at short intervals: at day 2, 4, 6, 8, 10, 12 and 23. The increase in the plasma level of epinephrine represents a maturation of the secretion of the adrenal medulla. The increase in plasma of epinephrine and norepinephrine and the content of catecholamines in the adrenal glands of both normal animals and those treated with either high doses of T4 or cortisol at birth suggest a slowing down of the normal development of epinephrine secretion. This was confirmed by inducing hypoglycemia in these three groups of animals by a 20-h fast or by insulin administration (0.1436 μmol/kg). We conclude that both high doses of T4 and cortisol administered at birth seem to retard the development of the autonomic nervous system similar to the effect on the central nervous system.


1959 ◽  
Vol 36 (3) ◽  
pp. 501-511
Author(s):  
M. J. WELLS

1. Octopuses blinded by section of the optic nerves were trained by means of 5-10 V. a.c. shocks to reject objects that they would otherwise take. 2. With trials at 3, 5, or 20 min. intervals, in which the test object was always presented to the same arm, animals learned within four or five trials, thereafter rejecting the test object whenever it was presented. 3. When, after a succession of such negative responses, the object was presented to another arm on the other side of the octopus, the result depended upon the rate of training before the change. Thus the object was taken in the trial immediately following the arm change in nineteen out of twenty-six sets of tests with trials at 3 or 5 min. intervals, but in only two out of twelve sets with trials at 20 min. intervals; further experiments in which changes were made between arms on the same side produced similar results. 4. These results are interpreted as showing that changes occurring as a result of experience directly affecting one arm take a period of several hours to spread and become effective in determining the reactions of the rest. This in turn implies the existence of functionally independent neurone fields representing the individual arms, and is discussed in relation to what is already known about the organization of the tactile system of the octopus.


Development ◽  
1994 ◽  
Vol 120 (5) ◽  
pp. 1151-1161 ◽  
Author(s):  
Y. Zhang ◽  
A. Ungar ◽  
C. Fresquez ◽  
R. Holmgren

Previous studies have shown that the segment polarity locus gooseberry, which contains two closely related transcripts gooseberry-proximal and gooseberry-distal, is required for proper development in both the epidermis and the central nervous system of Drosophila. In this study, the roles of the gooseberry proteins in the process of cell fate specification have been examined by generating two fly lines in which either gooseberry-distal or gooseberry-proximal expression is under the control of an hsp70 promoter. We have found that ectopic expression of either gooseberry protein causes cell fate transformations that are reciprocal to those of a gooseberry deletion mutant. Our results suggest that the gooseberry-distal protein is required for the specification of naked cuticle in the epidermis and specific neuroblasts in the central nervous system. These roles may reflect independent functions in neuroblasts and epidermal cells or a single function in the common ectodermal precursor cells. The gooseberry-proximal protein is also found in the same neuroblasts as gooseberry-distal and in the descendants of these cells.


Author(s):  
Andrea C. Adams

Many immune-mediated diseases and infections affect the central and peripheral nervous systems. The common feature that characterizes both immune-mediated diseases and infections is a subacute temporal profile. Immune-mediated disease can affect only the nervous system or involve the nervous system as part of a systemic illness, as in vasculitis and connective tissue disease. Multiple sclerosis (MS), the most common disabling neurologic illness of young people, is the prototypical immune-mediated disease of the central nervous system (CNS).


Oncoreview ◽  
2016 ◽  
Vol 6 (4) ◽  
pp. 0-0 ◽  
Author(s):  
Łukasz Galus

Ifosfamide is a cytostatic drug commonly used in chemotherapy. One of the common adverse effects resulting from the treatment with ifosfamide is encephalopathy. This paper describes a case study of a 64-year-old patient who suffered from a full-blown encephalopathy as a result of chemotherapy administered during the treatment of fibrosarcoma of the femur. It provides a hypothesis of the mechanism behind toxic effects of ifosfamide on the central nervous system and elaborates on a number of documented ways of preventing aforementioned complications.


2020 ◽  
Author(s):  
Shahrzad Nazari ◽  
Amirhossein Azari Jafari ◽  
Seyyedmohammadsadeq Mirmoeeni ◽  
Saeid Sadeghian ◽  
Mohammad Eghbal Heidari ◽  
...  

Background: At the end of December 2019, a novel respiratory infection, initially reported in China, known as COVID-19 initially reported in China, and later known as COVID-19, led to a global pandemic. Despite many studies reporting respiratory infections as the primary manifestations of this illness, an increasing number of investigations have focused on the central nervous system (CNS) manifestations in COVID-19. In this study, we aimed to evaluate the CNS presentations in COVID-19 patients in an attempt to identify the common CNS features and provide a better overview to tackle this new pandemic. Methods: In this systematic review and meta-analysis, we searched PubMed, Web of Science, Ovid, Embase, Scopus, and Google Scholar. Included studies were publications that reported the CNS features between January 1st, 2020, to April 20th, 2020. The data of selected studies were screened and extracted independently by four reviewers. Extracted data analyzed by using STATA statistical software. The study protocol registered with PROSPERO (CRD42020184456). Results: Of 2353 retrieved studies, we selected 64 studies with 11282 patients after screening. Most of the studies were conducted in China (58 studies). The most common CNS symptom of COVID-19 were Headache (8.69%, 95%CI: 6.76%-10.82%), Dizziness (5.94%, 95%CI: 3.66%-8.22%), and Impaired consciousness (1.9%, 95%CI: 1%-2.79%). Conclusions: The growing number of studies have reported COVID-19, CNS presentations as remarkable manifestations that happen. Hence, understanding the CNS characteristics of COVID-19 can help us for better diagnosis and ultimately prevention of worse outcomes.


Sign in / Sign up

Export Citation Format

Share Document