Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024591 (malignant hyperthermia)
 2,353 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Myoadenylate deaminase deficiency, the most common of the known enzyme deficits of muscle, appears to occur in two forms. The primary type seems to be inherited as a complete gene block in an autosomal recessive pattern. Although occasionally diagnosed in infancy, when muscle biopsy is performed on a hypotonic but normoreflexic child, the deficiency is usually not symptomatic until adult or middle age, when muscle cramping and exercise intolerance develop. The skeletal muscle isozyme is immunologically, and presumably genetically, unique, and these patients have normal levels of adenylate deaminase in their other cells and tissues. A presumptive diagnosis can usually be made by an ischemic forearm exercise test, which shows a negligible increase in blood ammonia, despite a normal rise in lactate. Despite the absence of more than 99% of normal adenylate deaminase activity, the muscle biopsy shows no anatomic pathology, and other enzymes are at normal levels. These patients do not suffer progressive disease, and should be reassured and encouraged to maintain physical activity. The heterozygous state is probably asymptomatic, except, perhaps, on extreme exercise, but may be associated with an increased incidence of malignant hyperthermia susceptibility. Since the gene defect is not rare, it is not surprising that some cases of the deficiency will be coincidentally associated with other neuromuscular disease. However, there is also a secondary form of myoadenylate deaminase deficiency, consequent to muscle damage from other disease. In this form, the residual activity is higher (1-10% of normal), may present rare foci of positive stain in the section, and reacts normally with antibody to the muscle isozyme. Other muscle enzymes are also depleted, although not as severely, and the prognosis in such cases is dictated by the primary disease. Since the heterozygous state is common, these patients might have been carriers whose adenylate deaminase levels have been lowered to the deficient category by the advent of other neuromuscular disease.
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PMID:Myoadenylate deaminase deficiency: primary and secondary types. 378 46

Myoadenylate deaminase deficiency, the most common of the known enzyme deficits of muscle, appears to occur in two forms. The primary type seems to be inherited as a complete gene block in an autosomal recessive pattern. Although occasionally diagnosed in infancy, when muscle biopsy is performed on a hypotonic but normoreflexic child, the deficiency is usually not symptomatic until adult or middle age, when muscle cramping and exercise intolerance develop. The skeletal muscle isozyme is immunologically, and presumably genetically, unique, and these patients have normal levels of adenylate deaminase in their other cells and tissues. A presumptive diagnosis can usually be made by an ischemic forearm exercise test, which shows a negligible increase in blood ammonia, despite a normal rise in lactate. Despite the absence of more than 99% of normal adenylate deaminase activity, the muscle biopsy shows no anatomic pathology, and other enzymes are at normal levels. These patients do not suffer progressive disease, and should be reassured, and encouraged to maintain physical activity. The heterozygous state is probably asymptomatic, except, perhaps, on extreme exercise, but may be associated with an increased incidence of malignant hyperthermia susceptibility. Since the gene defect is not rare, it is not surprising that some cases of the deficiency will be coincidentally associated with other neuromuscular disease. However, there is also a secondary form of myoadenylate deaminase deficiency, consequent to muscle damage from other disease. In this form, the residual activity is higher (1-10% of normal), may present rare foci of positive stain in the section, and reacts normally with antibody to the muscle isozyme. Other muscle enzymes are also depleted, although not as severely, and the prognosis in such cases is dictated by the primary disease. Since the heterozygous state is common, these patients might have been carriers, whose adenylate deaminase levels have been lowered for the deficient category by the advent of other neuromuscular disease.
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PMID:Myoadenylate deaminase deficiency: inherited and acquired forms. 400 19

Using portacaval anastomosis (PCA) rats as a model with or without injection of ammonium acetate, we investigated the effects of MHS-G on the abnormalities of electroencephalogram (EEG) and brain amines metabolism in comparison with those of SF-1008C, a commercial nutritional preparation for hepatic failure. MHS-G (0.68 g/kg, p.o.) clearly improved both the abnormalities of EEG (such as reduction of amplitude, increasing delta wave distribution and decreasing beta wave distribution) and brain amines metabolism (such as increasing of Trp and DOPAC content) after injection of ammonium acetate. Moreover, MHS-G significantly increased branched chain amino acid concentrations and decreased aromatic amino acid concentrations in plasma and brain in comparison with water, and it significantly decreased the ammonia level in plasma in comparison with water and SF-1008C. These results suggest that MHS-G has a positive effect on abnormalities of EEG and amino acids metabolism in the plasma and brain of PCA rats.
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PMID:[Effect of MHS-G, an amino acids granule, on hepatic encephalopathy in portacaval anastomosis rats]. 828 69