Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030552 (paresis)
 5,831 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The nucleoside analog 2',3'-dideoxycytidine (ddC) is a potent inhibitor of the reverse transcriptase of human immunodeficiency virus and a DNA chain terminator. In clinical trials in patients with acquired immunodeficiency syndrome, ddC treatment has been associated with a dose-limiting and dose-dependent, painful, sensorimotor peripheral neuropathy. In search of an animal model for ddC-induced neurotoxicity we studied 36 New Zealand White rabbits (3 males/3 females/group) given 0, 10, 50, 100, 150, or 250 mg/kg/day of ddC, by oral intubation, for 13 or 18 weeks. Rabbits in the 150 and 250 mg/kg/day groups were sacrificed at 13 weeks because of hematopoietic toxicity. After 16 weeks, rabbits in the 50 and 100 mg/kg/day groups showed hindlimb paresis and/or gait abnormalities. Nerve conduction velocities and amplitudes in the 100 mg/kg/day rabbits were reduced by 30 to 50%. The most prominent pathologic changes in peripheral nerve and ventral roots of ddC-treated rabbits were (a) myelin splitting and intramyelinic edema, (b) demyelination and remyelination of axons, and (c) axonal loss. Treatment-related histologic lesions were not observed in spinal cord, brain, or retina. The pathology in these ddC-treated rabbits is consistent with a peripheral myelinopathy and axonopathy. This represents the first clinical, electrophysiologic, and pathologic description of an animal model of a peripheral neuropathy induced by a nucleoside analog.
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PMID:Peripheral neuropathy induced by 2',3'-dideoxycytidine. A rabbit model of 2',3'-dideoxycytidine neurotoxicity. 130 30

Unprecedented mortality occurred in bald eagles (Haliaeetus leucocephalus) at DeGray Lake, Arkansas, during the winters of 1994-1995 and 1996-1997. The first eagles were found dead during November, soon after arrival from fall migration, and deaths continued into January during both episodes. In total, 29 eagles died at or near DeGray Lake in the winter of 1994-1995 and 26 died in the winter of 1996-1997; no eagle mortality was noted during the same months of the intervening winter or in the earlier history of the lake. During the mortality events, sick eagles were observed overflying perches or colliding with rock walls. Signs of incoordination and limb paresis were also observed in American coots (Fulica americana) during the episodes of eagle mortality, but mortality in coots was minimal. No consistent abnormalities were seen on gross necropsy of either species. No microscopic findings in organs other than the central nervous system (CNS) could explain the cause of death. By light microscopy, all 26 eagles examined and 62/77 (81%) coots had striking, diffuse, spongy degeneration of the white matter of the CNS. Vacuolation occurred in all myelinated CNS tissue, including the cerebellar folia and medulla oblongata, but was most prominent in the optic tectum. In the spinal cord, vacuoles were concentrated near the gray matter, and occasional swollen axons were seen. Vacuoles were uniformly present in optic nerves but were not evident in the retina or peripheral or autonomic nerves. Cellular inflammatory response to the lesion was distinctly lacking. Vacuoles were 8-50 microns in diameter and occurred individually, in clusters, or in rows. In sections stained by luxol fast blue/periodic acid-Schiff stain, the vacuoles were delimited and transected by myelin strands. Transmission electron microscopy revealed intramyelinic vacuoles formed in the myelin sheaths by splitting of one or more myelin lamellae at the intraperiodic line. This lesion is characteristic of toxicity from hexachlorophene, triethyltin, bromethalin, isonicotinic acid hydrazide, and certain exotic plant toxins; however, despite exhaustive testing, no etiology was determined for the DeGray Lake mortality events. This is the first report of vacuolar myelinopathy associated with spontaneous mortality in wild birds.
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PMID:Epizootic vacuolar myelinopathy of the central nervous system of bald eagles (Haliaeetus leucocephalus) and American coots (Fulica americana). 982 89

Transgenic mice expressing mutant (P301L) tau develop paresis, neurofibrillary tangles and neuronal loss in spinal motor neurons beginning at 4 to 6 months of age. Astrocytes and oligodendrocytes acquire filamentous tau inclusions at later ages. Here we report pathology in the spinal white matter of these animals. Progressive white matter pathology, detected as early as 2 months of age, was most marked in lateral and anterior columns, with sparing of posterior columns until late in the disease. Early changes in Luxol fast blue/periodic acid Schiff (LFB/PAS) and toluidine blue stained sections were vacuolation of myelin followed by accumulation of myelin figures within previous axonal tubes and finally influx of PAS-positive macrophages. Myelin debris and vacuoles were found in macrophages. At the ultrastructural level, myelinated axons showed extensive vacuolation of myelin sheaths formed by splitting of myelin lamellae at the intra-period line, while axons were atrophic and contained densely packed neurofilaments. Other axons were lost completely, resulting in collapse and phagocytosis of myelin sheaths. Also present were spheroids derived from swollen axons with thin myelin sheaths containing neurofilaments, tau filaments and degenerating organelles. Many oligodendrocytes had membrane-bound cytoplasmic bodies composed of tightly stacked lamellae capped by dense material. The vacuolar myelopathy in this model to some extent resembles that reported in acquired immune deficiency syndrome and vitamin B12 deficiency. The progressive axonal pathology is most consistent with a dying-back process caused by abnormal accumulation of tau in upstream neurons, while vacuolar myelinopathy may be a secondary manifestation of neuroinflammation.
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PMID:Progressive white matter pathology in the spinal cord of transgenic mice expressing mutant (P301L) human tau. 1690 61

A clinical-electroneuromyographical study of 40 children (32 (80%) of them aged from 12 to 17 years, mean age 13,9+/-1,8 years, and 8 (20%) - from 1 to 8 years, mean age 4,4+/-2,1 years) were studied in the acute period of facial nerve paralysis (FNP). Six (15%) children had FNP in the anamnesis. Among precipitating factors were the cold exposure the day before disease onset (20 (50%) patients), symptoms of flu (13 (32,5%) patients) and psycho-emotional tension (3 (7,5%) patients). No precipitation was noted in 4 (10%) children. The degree of muscle paresis was 81,9+/-7% that corresponded to clinical stages III-IV according to K. Rosler. An electroneuromyographical analysis of motor ortho- and antidromic response to the facial nerve stimulation on the side of paresis and on the contralateral side in patients and controls revealed the presence of proximal axon- and myelinopathy of facial nerve with the involvement of its own motorneurons and brain stem interneurons. The maintenance of wink reflex and F-wave blocks in the period over 3 weeks are prognostically unfavorable factors for restoration of mimic muscle function in the early stage of disease.
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PMID:[Clinical-electroneuromyographical characteristics of facial nerve paralysis in children]. 2003 48

Recurrent Laryngeal Neuropathy (RLN) is a highly prevalent and predominantly left-sided, degenerative disorder of the recurrent laryngeal nerves (RLn) of tall horses, that causes inspiratory stridor at exercise because of intrinsic laryngeal muscle paresis. The associated laryngeal dysfunction and exercise intolerance in athletic horses commonly leads to surgical intervention, retirement or euthanasia with associated financial and welfare implications. Despite speculation, there is a lack of consensus and conflicting evidence supporting the primary classification of RLN, as either a distal ("dying back") axonopathy or as a primary myelinopathy and as either a (bilateral) mononeuropathy or a polyneuropathy; this uncertainty hinders etiological and pathophysiological research. In this review, we discuss the neuropathological changes and electrophysiological deficits reported in the RLn of affected horses, and the evidence for correct classification of the disorder. In so doing, we summarize and reveal the limitations of much historical research on RLN and propose future directions that might best help identify the etiology and pathophysiology of this enigmatic disorder.
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PMID:Pathological classification of equine recurrent laryngeal neuropathy. 2969 4