glycogen storage disease

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glycogen

 [gli´ko-jen]
a polysaccharide that is the chief carbohydrate storage material in animals, being converted to glucose by depolymerization; it is formed by and largely stored in the liver, and to a lesser extent in muscles, and is liberated as needed.
glycogen disease glycogen storage disease.
glycogen storage disease any of a group of genetically determined disorders of glycogen metabolism, marked by abnormal storage of glycogen in the body tissues. Type I is called gierke's disease; type II is called pompe's disease; type III is called forbes' disease; type IV is called amylopectinosis; type V is called mcardle disease; and type VI is called hers' disease. In type VII, a deficiency in phosphofructokinase affects muscle and erythrocytes, with temporary weakness and cramping of skeletal muscle after exercise. In type VIII, the enzyme deficiency is unknown, but the liver and brain are affected, with hepatomegaly, truncal ataxia, and nystagmus; the neurologic deterioration progresses to hypertonia, spasticity, and death. In type IX, a deficiency in liver phosphorylase kinase results in marked hepatomegaly, which may disappear in early adulthood. In type X, a lack of activity of cyclic AMP–dependent kinase affects the liver and muscle, with mild clinical symptoms. Called also glycogen disease and glycogenosis.

glycogen storage disease

n.
Any of various genetic diseases caused by deficiency of one of the enzymes involved in breaking down or synthesizing glycogen, resulting in storage of abnormal amounts or types of glycogen and often affecting the liver, muscles, or both. Also called glycogenosis.

glycogen storage disease

Etymology: Gk, glykys + genein + L, instaurare, to renew, dis, opposite of; Fr, aise, ease
any of a group of inherited disorders of glycogen metabolism. An enzyme deficiency or defect in glycogen transport causes glycogen to accumulate in abnormally large amounts in various parts of the body. Biopsy and chemical analysis reveal the missing enzyme. Also called glycogenosis.

glycogen storage disease, type Ia


glycogen storage disease, type Ib

a form of glycogen storage disease in which excessive amounts of glycogen are deposited in the liver and leukocytes. Some symptoms are similar to, but less severe than, those of glycogen storage disease, type Ia (von Gierke's disease). Additional symptoms include neutropenia and recurrent GI inflammatory disease. Biopsy of the affected organs reveals the absence of glucose-6-phosphatase translocase, an enzyme necessary for glycogen metabolism.

glycogen storage disease, type II


glycogen storage disease, type III


glycogen storage disease, type IV


glycogen storage disease, type V


glycogen storage disease, type VI


glycogen storage disease, type VII

A clinically benign autosomal recessive [MIM 232700] metabolic disorder caused by a deficit of glycogen phosphorylase [EC 2.4.1.1] encoded on 14q21-q22

glycogen storage disease

Glycogenosis Any of a group of 12 inherited AR defects in the ability to store and/or retrieve glucose from intracellular depots, resulting in accumulation of glycogen in liver, muscle, heart, kidney, and other tissues enzyme defects, and hepatosplenomegaly, cardiomegaly, mental retardation–eg, dancing eyes syndrome–GSD VIII
Glycogen storage disease
Type  Deficient enzyme
0 Hepatic glycogen synthetase
I Glucose-6-phosphatase
II Lysosomal acid maltase alpha-1,4 glucosidase
III Amylo-1,6 glucosidase ('debrancher' disease)
IV Amylo-1,4-1,6-trans-glucosidase–'brancher' disease
V  Myophosphorylase
VI Hepatic phosphorylase
VII Phosphofructokinase
VIII Inactive hepatic phosphorylase  

glycogen storage disease

any of a group of genetically determined disorders of glycogen metabolism, marked by abnormal storage of glycogen in the body tissues. Includes Pompe's disease, Cori's disease, phosphofructokinase deficiency. See also glycogenosis.
References in periodicals archive ?
No definite data exist on whether this is also true for type IB shortens lifespan.
Pinpointing a progenitor star at exactly the same location as a Type Ib supernova was the best way to test the theories about the genesis of this type of explosion," Kasliwal said.
Detailed analysis of different types of observations of the supernova confirmed that it was, indeed, a Type Ib, and that it reached full luminosity two weeks from its initial explosion.
A defect in the metabolic activation of sulfate in a patient with achondrogenesis type IB.
Undersulfation of proteoglycans synthesized by chondrocytes from a patient with achondrogenesis type IB homozygous for an L483P substitution in the diastrophic dysplasia sulfate transporter.
Achondrogenesis type IB is caused by mutations in the diastrophic dysplasia sulphate transporter gene.
Achondrogenesis type IB (Fraccaro): study of collagen in the tissue and in chondrocytes cultured in agarose.
Type Ib and Ic supernovae, in contrast, show strong emission lines of intermediate-mass elements, primarily oxygen and calcium.
Supernovae of Type Ib and Ic are roughly a fourth as luminous as those of Type Ia.
These observations suggest that Type Ia supernovae come from relatively older, and hence less massive, stars than objects of Type Ib, Ic, and II.
Some theorists initially proposed that Type Ib and Ic blasts result from thermonuclear runaway in peculiar white dwarfs.