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Query: UMLS:C0004134 (ataxia)
 15,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The epidemiological, clinical, electrophysiological and nerve biopsy findings of 3 cases of n-hexane neuropathy in shoe industry are reported. The disease affects more than 1 person working in the same environment, regardless of their specific role, and occurs in factories where standards of hygiene are low. In the most severe cases the picture of peripheral neuropathy is associated with symptoms suggesting a concurrent involvement of the central nervous system such as dysarthria, disproportionate ataxia of the gait, blurred vision, and sometimes, after the recovery of the peripheral neuropathy, appearance of leg spasticity. Light- and electron microscopic study of peripheral nerve biopsies shows that the toxic produces a primary axonopathy characterized by segmental swellings of the fibers, due to accumulation of filaments. Retraction of the myelin from the node and segmental demyelination are secondary to the axonal changes. Experimental models of hexacarbon neurotoxicity may offer an explanation for the anatomical substrate underlying the symptoms related to the involvement of the central nervous system.
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PMID:n-hexane polyneuropathy. An occupational disease of shoemakers. 624 7

Twelve cases of chronic sensorimotor neuropathy associated with benign IgM paraproteinaemia are described. The onset was in the sixth or seventh decades and 9 cases were male. Tremor and ataxia were common features. The ESR was raised in 6 cases and the CSF protein content elevated in 10. There was severe reduction of motor nerve conduction velocity. Sera from all cases contained monoclonal IgM antibodies strongly reactive with human peripheral myelin, made up by the paraprotein. Histological studies on nerve biopsies taken from 8 cases all demonstrated a demyelinating neuropathy. Eight biopsies were examined by immunofluorescence. Monoclonal IgM was present on the myelin sheaths of surviving myelinated nerve fibres. The findings suggested that the neuropathy was of autoimmune origin and caused directly by the antimyelin antibody.
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PMID:Chronic demyelinating neuropathy associated with benign IgM paraproteinaemia. 633 2

Hens injected in one sciatic artery with diisopropylfluorophosphate (DFP) (0.184 mg/kg) developed monolateral ataxia on the injected side 10-12 days later. The inhibition of neuropathy target esterase (NTE) was 85% in the sciatic nerve of the injected leg and less than 60% in the contralateral sciatic nerve, in spinal cord and in brain. Other hens injected in the wing vein with the same dose of DFP showed low inhibition of NTE in the nervous system and did not develop delayed neuropathy. Hens injected in one sciatic artery with phenylmethanesulphonyl fluoride (PMSF) (1 mg/kg) and 24 hr later with high subcutaneous dose of DFP (1.1 mg/kg) developed monolateral ataxia 10-12 days later on the side not injected with PMSF. The level of NTE inhibition after PMSF was greater than 40% in the sciatic nerve on the injected side compared with less than 20% in other parts of the nervous system. The same dose of PMSF injected in the wing vein produced low NTE inhibition in the nervous system and failed to protect the animals from the same high systemic dose of DFP. We conclude that both toxic and protective effects of NTE inhibitors for delayed neuropathy are better related to the level of NTE inhibition in the peripheral nerve on the site of injection than to NTE inhibition in other parts of the nervous system. Furthermore we suggest that NTE inhibition should also be measured in the peripheral nerve in the standard toxicity testing for organophosphate-induced delayed neurotoxicity.
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PMID:Intra-arterial injection of diisopropylfluorophosphate or phenylmethanesulphonyl fluoride produces unilateral neuropathy or protection, respectively, in hens. 648 68

The reduction of neurogenic posttetanic potentiation in the slow twitch, soleus muscle is an index of impaired motor nerve function in cats with organophosphate-induced neuropathy. We have applied the measurement of posttetanic potentiation to study the functional state of the slow, tonic, plantaris muscle and its motor innervation in adult White Leghorn hens with tri-o-tolyl phosphate (TOTP)-induced neuropathy. At suitable intervals following single oral doses of vehicle or TOTP (500 mg/kg), nerve conduction velocity and posttetanic potentiation were measured in anesthetized hens. Conduction in the sciatic nerve was not altered by TOTP. The plantaris muscle of birds treated with vehicle (peanut oil) either failed to contract or responded to nerve stimulation at 0.4 Hz with very small twitches. Following nerve stimulation at frequencies inducing tetanus (50-140 Hz), the muscles responded with large, slow twitches that gradually decayed in amplitude. The area under the curve formed by the amplitude of these twitches over time (posttetanic potentiation) was directly proportional to the frequency and duration of nerve stimulation. In hens at 1,2, and 4 weeks following treatment with TOTP, the average amount of posttetanic potentiation was reduced concomitantly with the development of ataxia, paralysis, and pathological changes in the peripheral nerves. This difference between vehicle- and TOTP-treated hens was not significant, owing to large interbird variations. Since TOTP-treated hens showed greater disturbances in gait following moderate exercise, the fatigue of posttetanic potentiation with periodic neuronal stimulation was measured.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The function of motor nerves innervating slow tonic skeletal muscle in hens with delayed neuropathy induced by tri-o-tolyl phosphate. 650 74

Central and peripheral nerve fibre damage has been produced in Long-Evans hooded male rats with tri-ortho-cresyl phosphate. Animals were dosed by gavage with intermittent or daily amounts of the organophosphate and examined after 2, 6, 12, 18 and 24 weeks. The distribution of central nervous system (spinal cord) damage and the differential vulnerability among various peripheral nerves supported a "dying-back' classification for the neuropathy. Giant axonal swellings, containing massive accumulations of smooth endoplasmic reticulum, hallmarked the neuropathy. In spite of severe neurological damage the animals displayed only moderate functional disturbances. These findings have shown that the rat is highly sensitive to the structural damage caused by organo-phosphates, although resistant to the ataxia.
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PMID:A rodent model of organophosphorus-induced delayed neuropathy: distribution of central (spinal cord) and peripheral nerve damage. 652 45

Percutaneously inserted spinal cord electrical stimulation (PISCES) was carried out in eleven intractable pain cases and in one spastic paraplegic case. The causes of intractable pain constitute subacute myelo-optic neuropathy (SMON) 6 cases, cerebrovascular disease 2 cases, multiple sclerosis (MS) 1 case, Charcot-Marie-Tooth (CMT) 1 case and transverse myelitis (TM) 1 case. The cause of spastic paraplegia was due to the ossification of posterior longitudinal ligament (OPLL). A trial stimulation was performed about two weeks before planning a permanent implantation of PISCES system. For the trial stimulation, epidural electrodes were percutaneously inserted with a guide of fluoroscopy in a X-ray room. The conditions of stimulation were adjusted to give an optimal electric dysesthesia. We employed pulse width 0.1-1.0 msec, pulse rate 1-120 Hz and pulse amplitude 0-10 Volt. If an excellent effect was obtained by trial study, we proceeded to the chronic implantation of PISCES system which were composed of epidural electrodes, a subcutaneous receiver and a surface antenna. The procedure of implantation was carried out in an operating room under local anesthesia. In our series, seven subjects (58%) experienced a rewarding effect by the trial stimulation and three underwent the permanent implantation of PISCES. We summarized the clinical courses of these three cases which were OPLL, CMT and SMON. Compared with the other methods for pain relief, PISCES is most characteristic in its safety and simplicity. To date, PISCES has been applied to various disorders; such as ataxia, spasticity, intractable pain, neurogenic bladder and peripheral vascular disease. But its efficacy has not been established in all these disorders.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Our experiences of PISCES (percutaneously inserted spinal cord electrical stimulation) in SMON and other neurologic disorders]. 661 Nov 63

The effect of cobalamin inactivation by the anaesthetic gas nitrous oxide on the concentration of S-adenosylmethionine (Ado Met) in brain and liver of fruit bats (Rousettus aegyptiacus) was examined. Test animals exposed to N2O-oxygen (50:50, v/v) developed ataxia and paralysis leading to death after an average of 9.8 weeks (n6). Animals receiving pteroylmonoglutamic acid supplements in the diet became ataxic earlier (mean 8.8 weeks) while those receiving methionine supplements survived for significantly longer periods (12.5 weeks, P less than 0.01). Plasma cobalamin levels indicated severe depletion of cobalamin stores in N2O-exposed animals. The mean concentration of Ado Met in the brain of N2O-treated bats was nearly 50% higher than that of untreated controls. Ado Met levels in treated bats receiving pteroylmonoglutamic acid or methionine supplements were respectively 18 and 25% higher than in controls. In contrast, the concentration of Ado Met in the liver of all the N2O-treated groups was slightly lower than in controls. These results suggest that the N2O-induced neuropathy in the fruit bat is not related to a depletion of Ado Met in the nervous system.
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PMID:Tissue S-adenosylmethionine levels in fruit bats (Rousettus aegyptiacus) with nitrous oxide-induced neuropathy. 661 64

Phase three of the Quebec Cooperative Study of Friedreich's Ataxia was devoted to an understanding of the physiopathology of individual symptoms on the basis of previously discovered biochemical leads. The present paper attempts to pull these results together by presenting, as a hypothesis, a unifying scheme of possible interactions and relationships. The central core of this hypothesis is the demonstration in Friedreich's ataxia of a state of mitochondrial energy deprivation. This is indirectly responsible for such associated and important symptoms as muscle weakness, dying-back neuropathy, scoliosis and hypertrophic cardiomyopathy. Secondarily, and possibly as an independent but linked-event, the entry of glucose into cells and pyruvate oxidation, are slowed down, favoring the development of diabetes. As a consequence, tissue concentrations of glutamic acid and aspartic acid are decreased, particularly in more vulnerable areas such as the cerebellum, brain stem and dorsal root ganglia. This tissue deficiency in putative excitatory neurotransmitters is directly responsible for the symptom of ataxia. This conclusion is reinforced by the correction of the ataxia in experimental animals, by the intraventricular injection of the same amino acids, and not by the injection of other stimulants of motricity. The observed mitochondrial energy deprivation could be the metabolic consequence of major changes in the linoleic acid (18.2) composition of inner mitochondrial membrane phospholipids, such as cardiolipin. Such decreases in membrane 18:2 could be the result of interference with the normal incorporation of this fatty acid to lipoproteins and/or cell membranes. It is at this level that the search for the specific enzyme defect in Friedreich's ataxia is continuing.
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PMID:Friedreich's ataxia 1980. An overview of the physiopathology. 678 90

Acrylamide, a widely used and chemically active substance, has caused delayed distal neuropathy in man and in experimental animals. Male rats administered 50 mg/kg/day acrylamide for 5 days demonstrated ataxia in preliminary rotorod experiments. Additional groups of rats were dosed with 5, 15 or 50 mg/kg/day acrylamide for 5 days, then sacrificed on day 6 at various time intervals after iv injections of tritiated tyrosine (Tyr) or tryptophan (Trp). Brain levels of Tyr, Trp, norepinephrine (NE), dopamine (DA), serotonin (5-HT), and respective metabolites, 3-methoxy-4-hydroxyphenylethyleneglycol sulfate (MOPEG-sulfate), 3,4-dihydroxyphenylacetic acid (DOPAC), and 5-hydroxyindoleacetic acid (5-HIAA) were assayed fluorometrically. Turnover rates of NE, DA and 5-HT were estimated by evaluating the rates of specific activity changes in neurotransmitters and precursor amino acids over time. A slight reduction of whole brain NE content was observed in rats administered 50 mg/kg/day acrylamide. Other neurotransmitter levels were not affected by acrylamide levels administered, nor were turnover rates affected. Levels of MOPEG-sulfate and DOPAC were unchanged at any dose tested. Increased levels of 5-HIAA were observed in rats receiving 15 and 50 mg/kg/day acrylamide. Results suggest that acrylamide neurotoxicity does not entail widespread damage to the neurons associated with these biogenic amines; however, the acid metabolite efflux from brain was significantly inhibited.
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PMID:Evaluation of acrylamide treatment on levels of major brain biogenic amines, their turnover rates, and metabolites. 688 32

O-n-Propyl O-(2-propynyl) phenylphosphonate (NIA-16388), which has been recommended for use as insecticide synergist, was synthesized and tested for acute and neurotoxicities in hens. The 24-h LD50 value of this compound in the hen was found to be about 340 mg/kg. Hens treated with this compound at 400 mg/kg with atropine sulfate as an antidote developed clear clinical signs of delayed neurotoxicity 12-17 d after single oral treatment. The signs of neurotoxicity gradually progressed from ataxia through paralysis. Biochemical tests indicated that at the tested dose level of this compound, the level of hen-brain neurotoxic esterase (NTE) was inhibited in vivo to less than 10% of the normal level 1 d after treatment. These clinical and biochemical signs of neurotoxicity are supported by histopathological findings. Degenerative lesions of axons were observed in the NIA-treated group of hens. The lesions in the spinal cord were seen most frequently and most prominently in the lateral columns, although they sometimes were observed in other areas, e.g., in the anterior columns (especially in thoracic and lumbar sections). Generally, the lesions were more apparent in the longitudinal sections than in the cross-sections. Two other phenylphosphonate derivatives, O-ethyl S-benzyl phenylphosphonothioate (ESBP) and O-methyl O-(4-benzylidenylphenylhydrazone) phenylphosphonothioate, were also synthesized and tested for neurotoxicity to hens. The LD50 values for these two compounds in the hen were more than 1000 mg/kg. No signs of delayed neuropathy were detected in hens given either ESBP or the hydrazone compound at single oral doses of 1000 mg/kg.
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PMID:Delayed neuropathy in hen by the insecticide synergist O-n-propyl O-(2-propynyl) phenylphosphonate (NIA-16388) and other phenylphosphonate esters. 716 38


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