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)

We report a right-handed 22-year-old man with muscle atrophy. His prenatal course and the delivery were uneventful, but he walked unsupported at 15 months of the age for the first time. He was apparently well but he was in the slowest group in running in schools. He noted a difficulty in climbing up stairs at 19 years of the age, and he was admitted to our hospital for the work up when he was 22-year-old. His family history and past medical history were unremarkable. On admission, he was a slender and tall guy in no acute distress. General physical examination was unremarkable, but he had high-arched palate and high-arched feet. On neurologic examination, mental status and higher cerebral functions were normal. Cranial nerves appeared intact, however, he had a thin and long face without weakness. The sternocleidomastoid muscles appeared somewhat atrophic and were moderately weak. He was able to walk normally, however, he needed a handrail when he went up stairs. Thigh muscles and triceps surae muscles were atrophic and slightly weak (4/ 5). Muscle tone was hypotonic and no deep tendon reflexes were elicited except for jaw jerk. No ataxia or involuntary movements were seen; sensation was intact. Laboratory examination was unremarkable except for slight increase in serum CK to 145 IU/L. An ischemic forearm exercise test revealed slight elevation of lactate and pyruvate in that base line levels were 5.4 mg/dl and 0.52 mg/dl, respectively, which rose to 11.4 mg/dl and 0.85 mg/dl, respectively, 20 minutes after the initiation of the ischemic exercise. The base line serum ammonia was 102.5 micrograms/dl which decreased to 64.8 micrograms/dl at 20 minutes. A diagnostic biopsy was performed from the left quadriceps femoris muscle. The patient was discussed in a neurologic CPC, and the chief discussant arrived at the conclusion that the patient had nemaline myopathy. Opinions were divided between nemaline myopathy and debranching enzyme deficiency. The results of the ischemic exercise was not typical of glycogen storage disease, but elevations of lactate and pyruvate did not appear to be sufficient to be interpreted as normal. Histologic examination of the biopsied specimen revealed marked type I fiber predominance and abundant nemaline rods. Cytoplasmic bodies were also seen. Histologic characteristics were consistent with the diagnosis of nemaline myopathy. The possibility of concomitant presence of AMP deaminase deficiency was discussed, because serum ammonia did not elevate in the ischemic exercise test.
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PMID:[A 22-year-old man with long-standing weakness and atrophy predominantly in the lower extremities]. 879 13

In cattle with hepatic lipidosis, hepatic abscessation, leptospirosis, biliary calculi or fasciolosis, the progression of the disease was studied by serial measurements of serum total bile acid concentrations, plasma glutamate dehydrogenase, gamma-glutamyltransferase, 5'-nucleotidase and leucine aminopeptidase activities Terminalia avicennioides and by liver biopsy. Regardless of the cause of the hepatic disease, weight loss, anorexia, dullness and depression were consistent features. Signs of hepatic encephalopathy, such as blindness, head pressing, excitability, ataxia and weakness were less common and, together with pyrexia and jaundice, were grave prognostic signs. Plasma ammonia concentrations were significantly elevated compared to clinically normal cattle, but such changes were not always accompanied by a decline in plasma urea concentrations. In normal, healthy cattle, the plasma ammonia:urea concentration ratio is 9:1 and the plasma ammonia:glucose concentration is 11:1. In hepatic disease, a plasma ammonia:glucose ratio > 40:1 or plasma ammonia:urea ratio > 30:1, particularly with a rising total ketone body concentration and a declining glucose concentration, carried a guarded prognosis. The study suggested that other factors, such as hypokalaemia, alkalosis, short-chain volatile fatty acids, and false and true neuro-transmitters, may be important in the pathogenesis of hepatic coma in cattle.
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PMID:Clinical and pathological studies in cattle with hepatic disease. 909 45

The purpose of this study was to determine the time of onset, duration, and the efficacy of in vivo gene transfer in protecting the ornithine transcarbamylase deficient spf/Y mouse from an acute ammonium challenge. The animals were challenged with ammonia (10 mmol/kg NH4Cl) 1, 2, 7, 14, or 28 d after the administration of a recombinant adenoviral construct deleted in E1 and with a temperature sensitive mutation in E2. Although there was no protection with the control LacZ virus, the ornithine transcarbamylase (OTC)-containing vector provided partial protection from both behavioral symptoms (ataxia, seizures, and abnormal response to sound) and biochemical abnormalities (ammonium, aspartate, alanine, and glutamine) within 24 h and complete protection by 48 h. Mortality was also decreased. Animals receiving the vector 7 and 14 d before the ammonium load were also protected, whereas those treated 28 d before the challenge were not. OTC enzyme activity in liver of untreated spf/Y mice was 5% of control C3H mice. After gene transfer, activity was increased to near control levels through 14 d but had returned to baseline by 28 d. These studies indicate that adenovirus-mediated gene transfer confers a metabolic benefit within 24 h of administration and provides protection against an acute metabolic insult for at least 2 wk.
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PMID:Adenovirus-mediated in vivo gene transfer rapidly protects ornithine transcarbamylase-deficient mice from an ammonium challenge. 909 55

A 18-year-old Dutch Warmblood mare was referred for colic. Upon arrival, lethargy, blindness, head pressing, ataxia, and circling were the main clinical signs. On rectal examination a hard mass and oedema around the cranial mesenteric artery were palpated. Plasma liver enzyme activities and the ammonia level were elevated. Atrial fibrillation with a pulse frequency of 36-52 beats per minute was noticed. On both sides a holosystolic murmer with the maximum intensity on the right side could be auscultated. Postmortem examination revealed eccentric hypertrophy of the right atrium and a pale spotted myocardium, most prominently of the right ventricle, with secondary venous congestion of the azygos and mesenteric veins. The liver changes were indicative of chronic congestion. Despite the normal pulse rate, it appeared that congestive heart failure due to cardiomyopathy, was responsible for the presenting symptoms of this patient.
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PMID:Atrial fibrillation associated with central nervous symptoms and colic in a horse: a case of equine cardiomyopathy. 956 65

Neuropsychiatric symptoms of hyperammonaemia include alterations of mood and personality, cognitive impairment, ataxia, convulsions and coma. The nature and severity of CNS dysfunction depend upon the aetiology and degree of hyperammonaemia, its acuteness of onset and the age of the patient. Neuropathological studies reveal Alzheimer type II astrocytosis in the adult hyperammonaemic patient, whereas hyperammonaemia in the infant resulting from congenital urea cycle disorders or Reye syndrome is accompanied by cerebral atrophy, neuronal loss and cerebral oedema. Several electrophysiological and biochemical mechanisms have been proposed to explain the deleterious effects of ammonia on CNS function. Such mechanisms include direct effects of the ammonium ion on excitatory and inhibitory neurotransmission and a deficit in cerebral energy metabolism due to ammonia-induced inhibition of alpha-ketoglutarate dehydrogenase. In addition, ammonia has been shown to interfere with normal processes of uptake, storage and release of various neurotransmitters. Ammonia disrupts monoamine storage, inhibits the high-affinity uptake of glutamate by both astrocytic and neuronal elements and activates 'peripheral-type' benzodiazepine receptors leading to the potential synthesis of neuroactive steroids in brain. On the basis of these actions, it has been proposed that ammonia disrupts neuron-astrocyte trafficking of amino acids and monoamines in brain. The increased formation of brain glutamine in hyperammonaemic syndromes could be responsible for the phenomenon of brain oedema in these disorders. Therapies aimed at either decreasing ammonia production in the gastrointestinal tract or increasing ammonia removal by liver or skeletal muscle are the mainstay in the prevention and treatment of the CNS consequences of hyperammonaemia. New therapeutic approaches aimed at correction of the neurotransmitter and cerebral energy deficits in these syndromes could hold promise for the future.
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PMID:Effects of hyperammonaemia on brain function. 968 41

In forty-five Holstein Frisian dairy cows (1-6 weeks post partum; mean age: 5.1 +/- 1.2 years) the serum total bile acid concentrations (SBA) were measured enzymatically. In all cows a left sided abomasal displacement was corrected surgically by right side laparotomy and omentopexy three days before investigation. The liver fat content was determined in all cows histologically. Liver failure was assumed if typical clinical signs (ataxia, general depression, recumbency or coma), an increased venous plasma ammonia level (> 35 mumol/l) and a decreased plasma amino acid index (< 4.0) were found. Cows without liver failure (N = 29) were grouped according to the liver fat content as cows with mild (N = 5), moderate (N = 19) or severe hepatosteatosis (N = 5). Histological examination of liver biopsies in cows with liver failure (N = 16) revealed in twelve cases a severe fatty liver and in four cases a hydropic degeneration of the liver tissue. Although in cows without liver failure mean SBA concentrations were higher in the group with moderate (47.3 +/- 30.9 mumol/l) or severe fatty liver (32.9 +/- 21.7 mumol/l) than in that with mild lipidosis (18.0 (16.8 mumol/l), differences were not significant. The mean SBA concentration in cows with liver failure (70.5 +/- 49.5 mumol/l) was only significantly (p < 0.05) increased compared to cows with uncomplicated mild hepatic lipidosis. In conclusion, the determination of SBA concentrations is of little value in the recognition of fatty liver or even liver failure due to the considerable variance of SBA concentrations in dairy cows.
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PMID:Total serum bile acid concentrations in dairy cows with fatty liver and liver failure. 1002 57

Six enzyme defects of the urea cycle have been described. Ornithine transcarbamylase deficiency is the most frequent of these diseases. The cumulative frequency is 1:8000. Most patients become symptomatic in childhood, but onset of symptoms may occur later in childhood or even adulthood. The patients present with recurrent episodes of an unspecific acute encephalopathy, seizures and clouding of consciousness to a variable degree. Focal neurological signs such as hemiparesis, aphasia or ataxia may also occur. These episodes may be triggered by infection, protein overload or drugs. Diagnostic are increased blood ammonia levels. Characteristic patterns of plasma amino acids and the determination of orotic acid in the urine mostly discriminate the individual disorders. Further diagnostic steps include the allopurinol challenge test, liver or skin biopsy for measurement of enzyme activity and molecular genetic studies. Treatment requires restriction of protein intake, supplementation of arginine and activation of alternative pathways of nitrogen excretion with benzoate or phenylbutyrate. Untreated, the acute episode may be lethal. Long-term treatment improves the clinical outcome considerably. Urea cycle defects should be included in the differential diagnosis of any encephalopathy or coma of unclear origin, and blood ammonia should be determined early in the evaluation of such patients.
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PMID:[Enzyme defects of the urea cycle in differential acute encephalopathy diagnosis in adulthood. Diagnosis and current therapy concepts]. 1009 45

A 58-year-old woman began to show ataxia at age 45 and dysarthria at age 56. Neurological examination revealed slurred speech, truncal ataxia, and pyramydal sign. Neither history of alcoholism nor hereditary factors were found. The level of serum ammonia was increased. Brain MRI study showed a high signal intensity in the cerebral peduncle and globus pallidus and mild cerebellar atrophy on T1-weighted image. A portal-systemic shunt due to a shunt vessel was found between the left splenic and kidney veins although she did not show any other symptoms or signs due to liver cirrhosis. Her symptoms dramatically improved by an intravenous administration of branched amino acid. The present case suggests an importance in finding a treatable cerebellar ataxia.
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PMID:[Portal-systemic shunt with cerebellar ataxia as the initial neurological manifestation which was dramatically improved by an intravenous administration of branched amino acid]. 1186 49

Experimental evidence indicates that ammonia causes neuroexcitation and seizures. This contrasts with the lethargy, confusion and other manifestations of global CNS depression commonly considered to be major components of hyperammonemic encephalopathies. Substantial data now indicates that ammonia can modulate GABAergic neurotransmission through direct and indirect mechanisms. This modulation consists of an enhancement of GABAergic neurotransmission at concentrations commonly encountered in hyperammonemic states and precedes the suppression of inhibitory neuronal function observed at higher (>1mM) ammonia concentrations. Not only is this increase in GABAergic neurotransmission consistent with the clinical picture of lethargy, ataxia and cognitive deficits associated with liver failure and congenital hyperammonemia, but it also provides a mechanism for testing new therapeutic modalities for the treatment of hyperammonemic encephalopathy.
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PMID:Direct and indirect enhancement of GABAergic neurotransmission by ammonia: implications for the pathogenesis of hyperammonemic syndromes. 1202 Jun 12

Methionine tablets are used as urinary acidifiers for pets and to decrease damage from dog urine to lawns. A 39-kg Labrador Retriever ingested approximately 350 tablets containing 150 mg methionine/tablet and was presented after repeated episodes of vomiting. The only abnormality was posterior ataxia suggestive of spinal cord injury. The animal was treated with i.v. fluids, steroids and gastrointestinal protectants. Approximately 4.5 h after entering the clinic the dog had a single seizure episode lasting 2-3 min which was treated with phenobarbital. Serum ammonia at that time was normal (0.19 mg/dL). The animal did not show further CNS abnormalities and awoke apparently normal. A musty odor to the breath was noticed through the course of the day, possibly due to volatile mercaptans produced from methionine metabolism. The animal made an uneventful recovery and was discharged the next day.
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PMID:Overingestion of methionine tablets by a dog. 1464 Apr 82


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