Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004134 (ataxia)
 15,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Twenty-seven sheep were assigned to three groups in order to study acute urea toxicity. Groups I, II and III were dosed with 0.5, 0.6 annd 0.75 g/kg of urea, respectively. The mean survival times were 165, 109 and 60 minutes, respectively. The following clinical signs such as pronounced muscle fasciculation, trembling, grinding teeth, ataxia, lateral recumbency, bloating, regurgitation, hyperesthesia, mydriasis and convulsions were observed. Anuria and lack of salivation were also present. The primary cause of death in this study was due to respiratory arrest and not cardiovascular collapse. Plasma examinations showed a marked increase in glucose, ammonia and urea levels but no change in ketone body concentration.
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PMID:Acute urea toxicity in sheep. 64 59

Siblings, aged 9 and 7 years, had simultaneous onset of vomiting, disorientation, ataxia, and coma. Both children had prodromal symptoms of upper respiratory tract infections, and had been treated with large doses of aspirin. Laboratory data showed evidence of hepatocellular dysfunction, with an elevated serum ammonia level in one patient; salicylate levels were 50 and 44 mg/100 ml. The child who died had autopsy evidence of cerebral edema and fatty liver. The difficulty in clinically differentiating Reye syndrome from salicylate intoxication is discussed.
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PMID:Acute encephalopathy in siblings. Reye syndrome vs salicylate intoxication. 125 38

Subacute necrotizing encephalopathy (Leigh syndrome) is characterized by lactacidosis, seizures, ataxia, multiple cerebral hypervascularized lesions and mitochondrial oxidation defects. This is a report on a 21-year-old patient with proven Leigh syndrome, mild central and provokable peripheral lactacidosis, an extra-erythrocyte complex II defect, functionally reduced myokinase adenylate deaminase activity, but no ultrastructural mitochondrial changes. Determination of lactate, pyruvate and ammonia under ischemic conditions plus a pyruvate loading test were particularly useful. Oral flunarizine (Sibelium 30 mg/d) proved to be therapeutically effective.
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PMID:Diagnosis and treatment in a case of juvenile subacute necrotizing encephalopathy Leigh without cytochrome c oxidase deficiency. 132 78

The medical records of 18 dogs that had hepatic disease and received phenobarbital as an anticonvulsant for 5 to 82 months were reviewed. Clinical signs included sedation and ataxia in all dogs, 5 dogs were also anorectic, 2 had coagulopathy, 3 were icteric, and 5 had ascites. Serum biochemical analysis revealed serum albumin concentration less than or equal to 2.2. g/dl in 12 dogs, serum alkaline phosphatase activity greater than or equal to 169 U/L in 18 dogs, serum alanine transaminase activity greater than or equal to 57 U/L in 15 dogs, and total bilirubin concentration greater than or equal to 1 mg/dl (in the absence of lipemia) in 7 dogs. Serum phenobarbital concentration was greater than or equal to 40 micrograms/ml in 12 of 17 dogs. Sulfobromophthalein excretion was prolonged in 8 of 10 dogs. Preprandial serum bile acid concentrations were high in 8 of 10 dogs, and 2-hour postprandial serum bile acid concentrations were high in 9 of 10 dogs. Two of 4 dogs tested had resting plasma ammonia concentrations greater than 200 mg/dl. An ammonia tolerance test was performed on 2 other dogs; both had ammonia concentration greater than or equal to 200 mg/dl in the plasma 30 minutes after receiving 100 mg of ammonium chloride/kg of body weight, PO. Nine dogs died, 1 was euthanatized, and necropsies were performed on these 10 dogs. Biopsies and necropsies of 6 dogs revealed chronic hepatic fibrosis with nodular regeneration (cirrhosis). One dog had hepatocellular carcinoma and mild cirrhosis. In 1 dog, after phenobarbital had been withheld, necropsy revealed complete recovery of the previously observed lesions.
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PMID:Hepatotoxicity of phenobarbital in dogs: 18 cases (1985-1989). 174 13

Quantitative autoradiography was used to assess the densities of gamma-aminobutyric acid (GABAA) receptors in the brains of rats with a portacaval end-to-side shunt (PCA). The shunt alone induced only mild encephalopathy with ataxia and decreased locomotion. Aggravation of the encephalopathy was achieved by gavage feeding of packed erythrocytes or by induction of severe hyperammonemia by intraperitoneal injection of urease. Gavage feeding of erythrocytes led to severe encephalopathy in about 50% of the animals with PCA. The combination of PCA and urease treatment caused severe encephalopathy in every animal. The serum ammonia concentration increased 5 times normal by PCA alone, 20 times normal by gavage feeding of erythrocytes and more than 30 times normal by urease-treatment of the PCA-animals. For autoradiography, coronal slices were cut at the level of the hippocampal formation and through the cerebellum. Radioligand binding was measured using as a ligand 3H-muscimol, a specific GABAA receptor agonist. The specific binding of 3H-muscimol was assessed densitometrically in several microregions of cerebral cortex, hippocampus and cerebellar cortex. No significant differences were observed between the magnitude of ligand binding to specific microregions of brains from normal animals, animals with PCA without overt encephalopathy and animals with severe encephalopathy induced by a combination of PCA and gavage feeding of erythrocytes or urease treatment.
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PMID:[Autoradiography determination of the GABA(A) receptor density in the brain of rats with portacaval shunt]. 216 Jul 60

The intent of this paper is to review the recent literature on exercise-induced hyperammonemia (EIH) and to compare the current interpretations of ammonia accumulation during exercise with the recognized clinical symptoms of progressive ammonia toxicity. In doing so, we will speculate on possible exercise-induced symptoms of CNS dysfunction which could result from elevated ammonia during intense short-duration or prolonged exercise. Ammonia is a ubiquitous metabolic product producing multiple effects on physiological and biochemical systems. Its concentration in several body compartments is elevated during exercise, predominantly by increased activity of the purine nucleotide cycle (PNC) in skeletal muscle. Depending on the intensity and duration of exercise, muscle ammonia may be elevated to the extent that it leaks (diffuses) from muscle to blood, and thereby can be carried to other organs. The direction of movement of ammonia or the ammonium ion is dependent on concentration and pH gradients between tissues. In this manner, ammonia can also cross the blood-brain barrier (BBB), although the rate of diffusion of ammonia from blood to brain during exercise is unknown. It seems reasonable to assume that exhaustive exercise may induce a state of acute ammonia toxicity which, although transient and reversible relative to disease states, may be severe enough in critical regions of the CNS to affect continuing coordinated activity. Regional differences in brain ammonia content, detoxification capacity, and specific sensitivity may account for the variability of precipitating factors and latency of response in CNS-mediated dysfunction arising from an exercise stimulus, e. g., motor incoordination, ataxia, stupor. There have been numerous suggestions that elevated ammonia is associated with, or perhaps is responsible for, exercise fatigue, although evidence for this relies extensively on temporal relationships. Fatigue may become manifest both as a peripheral organ or central nervous system phenomenon, or combination of both. Thus, we must examine the sequential or concomitant changes in ammonia concentration occurring in the periphery, the central nervous system (CNS), and the cerebrospinal fluid (CSF) induced by any effector, not only exercise, to interpret and rationalize the diverse physical, physiological, biochemical, and clinical symptoms produced by hyperammonemic states. Since more is known about elevated brain ammonia during other diverse conditions such as disease states, chemically induced convulsion, and hyperbaric hyperoxia, some of these relevant data are discussed.
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PMID:Exercise-induced hyperammonemia: peripheral and central effects. 219 91

Patent ductus venosus was diagnosed in a 10-week-old Holstein heifer with acute onset of collapse and marked tenesmus. Additional clinical signs observed during the course of hospitalization included depression, anorexia, hind limb ataxia, bruxism, and poor growth. Clinicopathologic test results included high blood ammonia concentration, prolonged sulfobromophthalein half-life, and high serum bile acid concentration. Liver biopsy revealed mild periportal fibrosis, but no appreciable hepatocyte atrophy. Mesenteric portography and percutaneous ultrasonography confirmed the patent ductus venosus. An atrial septal defect prosthesis was placed in the ductus venosus, using a catheterization technique. After surgery, however, clinicopathologic test results were unchanged. Ultrasonography revealed that the prosthesis had pulled away from one side of the vessel. When the calf was 10.5 months old, surgical correction was achieved by a transhepatic ligation technique. Ultrasonography confirmed closure of the ductus venosus during and after surgery. Blood ammonia and serum bile acid concentrations and sulfobromophthalein half-life were normal 3 weeks after surgery. The calf had no further episodes of hepatoencephalopathy and was successfully bred at 18 months of age.
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PMID:Diagnosis and surgical correction of patent ductus venosus in a calf. 306 3

Portosystemic shunt was diagnosed in a 6-month-old Quarter Horse filly with acute onset of apparent blindness and a 3-month history of depression, lethargy, and ataxia. Clinicopathologic test results indicated slightly high gamma-glutamyl transpeptidase activity and serum total bilirubin concentration. Sulfobromophthalein half time was prolonged, and plasma ammonia and serum bile acid concentrations were high as well. Histopathologic findings of percutaneous liver biopsy included widespread hepatocyte atrophy and numerous prominent small arterioles in the area of the portal triad. On the basis of history, clinical findings, and clinicopathologic abnormalities, a presumptive diagnosis of portosystemic vascular anomaly was made. To confirm the tentative diagnosis, nuclear hepatic scintigraphy and operative mesenteric portography were performed. Medical treatment was unsuccessful, and the foal was euthanatized. Portosystemic shunts have been described in dogs and cats, but few cases have been reported in large animal species. Other, more common causes of neurologic abnormalities in foals, such as trauma, vertebral body abscesses, brain abscesses, and meningitis, must be ruled out before portosystemic shunt is considered.
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PMID:Clinical and diagnostic features of portosystemic shunt in a foal. 335 82

A 10-year-old boy with the hyperornithinemia, hyperammonemia and homocitrullinuria (HHH) syndrome is described. With dietary restriction of protein intake and supplementary administration of L-ornithine and L-arginine, the high concentration of ammonia decreased and the clinical signs of truncal ataxia and lethargy improved. A deficiency of ornithine transport into liver mitochondria was demonstrated biochemically, and glycogen granules and smooth surface endoplasmic reticulum were increased, but mitochondria showed normal construction ultrastructurally. Cranial computed tomography (CT) showed diffuse white matter low density and cerebellar vermis atrophy. The impairment of ornithine transport and energy production in the central nervous system may be related to the cranial CT findings and neurological signs.
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PMID:Clinical, biochemical and ultrastructural study on the pathogenesis of hyperornithinemia-hyperammonemia-homocitrullinuria syndrome. 340 56

Four families are described with an autosomal dominant illness characterized by the childhood onset of recurrent attacks of prolonged ataxia, server vertigo, and vomiting. The attacks often begin in infancy. On the average, attacks occur monthly, and last between one hour to more than a week. Variations in severity occur within families. During an attack, consciousness is unaltered, but severe vertigo makes walking impossible and vomiting is frequent and severe. An attack is marked by horizontal and vertical jerk nystagmus, accompanied by vertigo which is sometimes worsened by position; however, there is no muscular weakness. During an attack, blood gases, ammonia, and amino acid studies are normal. Between attacks patients manifest combinations of slight horizontal or vertical jerk nystagmus or mild clumsiness. Cochlear and labyrinthine studies and neurologic investigations were noncontributory. Conventional therapies for vertigo, epilepsy, and migraine were ineffective, but acetazolamide (250-500 mg/day) stopped the attacks.
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PMID:Dominant recurrent ataxia and vertigo of childhood. 350 70


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