Habituation of a monosynaptic response in vertebrate central nervous system: lateral column-motoneuron pathway in isolated frog spinal cord

1973 ◽  
Vol 36 (6) ◽  
pp. 1117-1130 ◽  
Author(s):  
P. B. Farel ◽  
D. L. Glanzman ◽  
R. F. Thompson
Development ◽  
1998 ◽  
Vol 125 (15) ◽  
pp. 2759-2770 ◽  
Author(s):  
M.P. Matise ◽  
D.J. Epstein ◽  
H.L. Park ◽  
K.A. Platt ◽  
A.L. Joyner

Induction of the floor plate at the ventral midline of the neural tube is one of the earliest events in the establishment of dorsoventral (d/v) polarity in the vertebrate central nervous system (CNS). The secreted molecule, Sonic hedgehog, has been shown to be both necessary and sufficient for this induction. In vertebrates, several downstream components of this signalling pathway have been identified, including members of the Gli transcription factor family. In this study, we have examined d/v patterning of the CNS in Gli2 mouse mutants. We have found that the floor plate throughout the midbrain, hindbrain and spinal cord does not form in Gli2 homozygotes. Despite this, motoneurons and ventral interneurons form in their normal d/v positions at 9.5 to 12.5 days postcoitum (dpc). However, cells that are generated in the region flanking the floor plate, including dopaminergic and serotonergic neurons, were greatly reduced in number or absent in Gli2 homozygous embryos. These results suggest that early signals derived from the notochord can be sufficient for establishing the basic d/v domains of cell differentiation in the ventral spinal cord and hindbrain. Interestingly, the notochord in Gli2 mutants does not regress ventrally after 10.5 dpc, as in normal embryos. Finally, the spinal cord of Gli1/Gli2 zinc-finger-deletion double homozygous mutants appeared similar to Gli2 homozygotes, indicating that neither gene is required downstream of Shh for the early development of ventral cell fates outside the ventral midline.


2018 ◽  
Vol 23 (1) ◽  
pp. 10-13
Author(s):  
James B. Talmage ◽  
Jay Blaisdell

Abstract Injuries that affect the central nervous system (CNS) can be catastrophic because they involve the brain or spinal cord, and determining the underlying clinical cause of impairment is essential in using the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), in part because the AMA Guides addresses neurological impairment in several chapters. Unlike the musculoskeletal chapters, Chapter 13, The Central and Peripheral Nervous System, does not use grades, grade modifiers, and a net adjustment formula; rather the chapter uses an approach that is similar to that in prior editions of the AMA Guides. The following steps can be used to perform a CNS rating: 1) evaluate all four major categories of cerebral impairment, and choose the one that is most severe; 2) rate the single most severe cerebral impairment of the four major categories; 3) rate all other impairments that are due to neurogenic problems; and 4) combine the rating of the single most severe category of cerebral impairment with the ratings of all other impairments. Because some neurological dysfunctions are rated elsewhere in the AMA Guides, Sixth Edition, the evaluator may consult Table 13-1 to verify the appropriate chapter to use.


1963 ◽  
Vol 44 (3) ◽  
pp. 475-480 ◽  
Author(s):  
R. Grinberg

ABSTRACT Radiologically thyroidectomized female Swiss mice were injected intraperitoneally with 131I-labeled thyroxine (T4*), and were studied at time intervals of 30 minutes and 4, 28, 48 and 72 hours after injection, 10 mice for each time interval. The organs of the central nervous system and the pituitary glands were chromatographed, and likewise serum from the same animal. The chromatographic studies revealed a compound with the same mobility as 131I-labeled triiodothyronine in the organs of the CNS and in the pituitary gland, but this compound was not present in the serum. In most of the chromatographic studies, the peaks for I, T4 and T3 coincided with those for the standards. In several instances, however, such an exact coincidence was lacking. A tentative explanation for the presence of T3* in the pituitary gland following the injection of T4* is a deiodinating system in the pituitary gland or else the capacity of the pituitary gland to concentrate T3* formed in other organs. The presence of T3* is apparently a characteristic of most of the CNS (brain, midbrain, medulla and spinal cord); but in the case of the optic nerve, the compound is not present under the conditions of this study.


1985 ◽  
Vol 55 ◽  
Author(s):  
F. Terry Hambrecht

ABSTRACTNeural prostheses which are commercially available include cochlear implants for treating certain forms of deafness and urinary bladder evacuation prostheses for individuals with spinal cord disorders. In the future we can anticipate improvements in bioelectrodes and biomaterials which should permit more sophisticated devices such as visual prostheses for the blind and auditory prostheses for the deaf based on microstimulation of the central nervous system.


1982 ◽  
Vol 60 (11) ◽  
pp. 1415-1424 ◽  
Author(s):  
H. B. Demopoulos ◽  
E. S. Flamm ◽  
M. L. Seligman ◽  
D. D. Pietronigro ◽  
J. Tomasula ◽  
...  

The hypothesis that pathologic free-radical reactions are initiated and catalyzed in the major central nervous system (CNS) disorders has been further supported by the current acute spinal cord injury work that has demonstrated the appearance of specific, cholesterol free-radical oxidation products. The significance of these products is suggested by the fact that: (i) they increase with time after injury; (ii) their production is curtailed with a steroidal antioxidant; (iii) high antioxidant doses of the steroidal antioxidant which curtail the development of free-radical product prevent tissue degeneration and permit functional restoration. The role of pathologic free-radical reactions is also inferred from the loss of ascorbic acid, a principal CNS antioxidant, and of extractable cholesterol. These losses are also prevented by the steroidal antioxidant. This model system is among others in the CNS which offer distinctive opportunities to study, in vivo, the onset and progression of membrane damaging free-radical reactions within well-defined parameters of time, extent of tissue injury, correlation with changes in membrane enzymes, and correlation with readily measurable in vivo functions.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Guojia Du ◽  
Yandong Li ◽  
Pan Wu ◽  
Xin Wang ◽  
Riqing Su ◽  
...  

Abstract Background To explore central nervous system (CNS) involvement in this disease, from the perspectives of diagnosis, treatment, and misdiagnosis Methods Twenty-eight patients with CNS echinococcosis were included in this retrospective study, including 18 males (64.3%) and 10 (35.7%) females. The average age of all the patients were 23.5 years (ranged 4–60 years). Twenty-three (23) patients (82.1%) received the first surgical resection in our hospital. Five (5) patients (17.9%) gave up surgical treatment for multiple-organ hydatidosis and previous surgery history at other hospitals, and albendazole was applied for a long-term (3–6 months) adjunct therapy for the 5 patients. The average follow-up time was 8 years. Results For the 28 patients, 23 cases received surgical treatments, and the diagnosis was confirmed by pathological examinations. The diagnosis of 4 cases of brain echinococcosis and 2 cases of spinal cord echinococcosis could not be confirmed, resulting in a misdiagnosis rate of 21.4% (6/28). For the pathological examination, a total of 17 cases were infected with Echinococcus granulosus (including 2 cases of spinal cord echinococcosis), and 6 cases were infected with Echinococcus alveolaris. Conclusion The diagnosis should be specifically considered in endemic regions. The clinical features of CNS hydatidosis were intracranial space-occupying lesions. For the treatment, the surgical removal of cysts should be necessary. In addition, the adjuvant therapy with drug and intraoperative prophylaxis is also suggested. The misdiagnosis may have resulted from atypical clinical features and radiographic manifestations, as well as the accuracy of hydatid immunologic test.


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