1,721,071 research outputs found
Changes in terminal sprout formation in rat sternocostalis muscle during chronic intoxication with 2,5 hexanedione
No full textQualitative and quantitative morphological studies of the sternocostalis muscle innervation were made on rats chronically intoxicated with 2,5 hexanedione (2,5 HD) using the zinc iodide‐osmium (ZIO) technique. Two distinct phases were seen in the events at the motor endplate. First, the number of motor endplates forming spontaneous terminal sprouts was found to increase linearly with time and, from the third week onward, the sprouts appeared to become progressively elongated. This latter change was associated with the appearance of swollen axons wihtin intramuscular nerve bundles. Second, from the sixth week onward, wallerian degeneration of nerve fibers was seen and terminal sprouts began to make new arborizations on muscle fibers. By the eighth week, this occurred in as many as 66% of the rats, and collateral sprouting was also observed at this time. The occurrence of increased spontaneous terminal sprouting due to altered neuromuscular function is discussed in the light of axonal changes resulting from nerofilament accumulation following 2,5 HD intoxication. Copyright © 1984 John Wiley & Sons, Inc
An unusual case of meningeal gliomatosis
No full textA case of meningeal gliomatosis following a primary spinal cord tumor is reported. The clinico-pathological features of this unusual extension of a spinal glioma are described. The rare incidence of this malignancy and its occurrence in young patients only are stressed. The possible pathophysiological events leading to the diffuse dissemination of the neoplastic cells are discussed
No mutation in the TRKA (NTRK1) geneencoding a receptor tyrosine kinase for nerve growth factor in a patient withhereditary sensory and autonomic neuropathy type V
No full textHereditary sensory and autonomic neuropathy type IV (HSAN-IV) and type V (HSAN-V) are autosomal recessive genetic disorders, both characterized by a lack of pain sensation. We report a girl with clinical and neurophysiological findings consistent with a diagnosis of HSAN-V. We sequenced her TRKA gene, encoding a receptor tyrosine kinase for nerve growth factor and responsible for HSAN-IV, but we could not detect any mutation. These data indicate that a gene (or genes) other than TRKA is probably responsible for HSAN-V in some patients
Neuroaxonal dystrophy with dystonia and pallidal involvement
No full textInfantile neuroaxonal dystrophy (INAD) is an autosomal recessive disease of infantile onset, characterised by progressive clinical course, multi-systemic involvement and widespread presence of dystrophic axons in both the central and peripheral nervous system. Clinical, neurophysiological and neuroradiological criteria of the disease are established, but the occurrence of atypical cases is known. Since the availability of molecular markers is still lacking, diagnostic evidence in vivo is provided by the presence of specific axonal lesions distally in the peripheral nerve fibres. In two children who had a protracted course of the disease with dystonic postures of the upper limbs and showed dystrophic axons following sural nerve biopsy, bilateral pallidal hypointensity was observed after T-2-weighted MRI scans. These findings are consistent with iron deposition, and are usually observed in Hallervorden-Spatz syndrome (HSS), a condition which is also characterised by dystrophic axons diffusely present in the central nervous system. but without peripheral nervous system involvement. These observations raise the issue of different phenotypes of INAD, and are consistent with the existence of intermediate forms between INAD and HSS. Altered mechanisms of iron storage and transport to and from the cellular compartments may play a role in the pathogenesis of the disease
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