Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.20 (alpha-glucosidase)
 4,237 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We performed single-fiber electromyography (SFEMG) and correlated the results with muscle-biopsy histochemistry in 56 patients with various neuromuscular diseases. Increased muscle-fiber density, delineated by SFEMG, was most prominent in diseases of ordinary denervation, namely motor neuron disorders and peripheral neuropathies, and it correlated with histochemical fiber type grouping. Both phenomena reflect denervation followed by reinnervation. In patients with central core disease and rod disease, fiber density was not increased despite massive type I fiber predominance. The normal distribution of type I fiber subtypes in those patients indicated tht their fiber predominance was not due to sprouting and reinnervation, but probably to paucity of the type II fibers. In type I fiber hypotrophy with central nuclei, fiber density was increased, perhaps attributable to the small diameter and consequent denser packing of the type I fibers. Fiber density was slightly increased in the majority of patients with acid-maltase deficiency, limb-girdle dystrophy, and polymyositis, in nearly half with mitochondrial myopathy, and in 1 older Duchenne dystrophy patient. In these myopathic disorders, myogenous deinnervation (followed by reinnervation) is one possible explanation. Normal fiber density was present in all patients with muscle phosphorylase deficiency, myotonia congenita, and in the hypokalemic periodic paralysis patients under age 40.
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PMID:Single-fiber electromyography in neuromuscular disorders: correlation of muscle histochemistry, single-fiber electromyography, and clinical findings. 810 13

Glycogen storage disease type II (GSDII) is an autosomal recessive lysosomal disorder caused by mutations in the gene encoding alpha-glucosidase (GAA). The disease can be clinically classified into three types: a severe infantile form, a juvenile and an adultonset form. Cases with juvenile or adult onset GSDII mimic limb-girdle muscular dystrophy or polymyositis and are often characterized by respiratory involvement. GSDII patients are diagnosed by biochemical assay and by molecular characterization of the GAA gene. Ascertaining a natural history of patients with heterogeneous late-onset GSDII is useful for evaluating their progressive functional disability. A significant decline is observed over the years in skeletal and respiratory muscle function. Enzyme replacement therapy (ERT) has provided encouraging results in the infantile form. It is not yet known if ERT is effective in late-onset GSDII. We examined a series of 11 patients before and after ERT evaluating muscle strength by MRC, timed and graded functional tests, 6-minute walk test (6MWT), respiratory function by spirometric parameters and quality of life. We observed a partial improvement during a prolonged follow-up from 3 to 18 months. The use of different clinical parameters in the proposed protocol seems crucial to determine the efficacy of ERT, since not all late-onset patients respond similarly to ERT.
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PMID:Progress in Enzyme Replacement Therapy in Glycogen Storage Disease Type II. 2117 24