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Query: UMLS:C1762617 (weakness)
 37,932 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A new type of hereditary muscle disease, characterized by weakness and painful spasms during effort, without electrical activity in the shortened muscles, is described. These phenomena are limited principally to the upper limbs. In addition we found electromyographical signs of a generalized myotonic syndrome. The histological and histochemical investigations reveal only minimal non-specific signs of myopathy. The activities of CPK and aldolase in the blood serum are increased at times. A normal elevation of venous lactate was observed during ischemic work. The biochemical studies of muscular tissue exhibit normal activities of the analyzed enzymes, especially as regards phosphorylase. An increased concentration of calcium ions in blood serum may be related to the contraction during strenuous work; it is known that calcium ions are an important factor in the contraction-relaxation cycle of striated muscle. The age of manifestation varied from 4 to 33 years in 4 cases of the relatives observed. The disease shows no signs of aggravation as to the severity and extent of the disorders. The nature of the underlying metabolic defect is still unknown.
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PMID:[Myopathia myotonica. A new type of hereditary muscle disease (author's transl)]. 5 Oct 68

A girl had generalized, rapidly progressive weakness beginning at age 4 weeks, and causing severe respiratory insufficiency and death at age 13 weeks. Histochemical and biochemical investigations of a muscle biopsy showed increased glycogen concentration and complete lack of phosphorylase activity. The enzyme protein appeared to be absent by immunodiffusion, and the metabolic block was documented by studies of anaerobic glycolysis in vitro. The biochemical basis for the unusual clinical picture is obscure, but muscle phosphorylase deficiency has to be considered in the differential diagnosis of the "floppy baby syndrome".
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PMID:Fatal infantile form of muscle phosphorylase deficiency. 10 96

Two brothers, 29 and 33 years of age, had recurrent myoglobinuria, renal failure and azotemia, but were otherwise normal, without apparent muscle weakness or exercise intolerance. Ischemic exercise resulted in normal lactate production. Muscle glycogen content and activities of phosphorylase and phosphofructokinase were normal. Plasma triglycerides were elevated (500 mg per deciliter) on a regular diet and rose during fasting. During a 72-hour fast, serum creatine phosphokinase rose more than 10 times, and myoglobin was detected in urine. Plasma ketone production was minimal during fasting, but prompt ketonemia ( a normal response) occurred after ingestion of medium-chain triglycerides. Carnitine palmityl transferase activity was virtually absent in crude muscle extracts and mitochondrial fractions. Lack of this enzyme impairs long-chain fatty acid utilization, reflected in increased content of plasma free fatty acids and plasma triglycerides. Depletion of ATP because of this metabolic block in muscle may account for the attacks of myoglobinuria.
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PMID:A disorder of muscle lipid metabolism and myoglobinuria. Absence of carnitine palmityl transferase. 12 38

In the differential diagnosis of intermittent claudication some rare myopathies have to be considered. The most frequent is phosphorylase deficiency (McArdle's disease). Exercise-induced muscular pain, weakness, contractures and occasionally myoglobinuria are the most prominent clinical signs. Serum creatine phosphokinase, aldolase and lactic dehydrogenase may be elevated after exertion. In the ischemic forearm test there is no rise of serum lactic acid. The enzyme deficiency can be demonstrated by histochemical and biochemical examination of a muscle specimen. Further, but more infrequent, enzymatic disturbances of glycolysis are phosphofructokinase deficiency and phosphohexoisomerase inhibitor, which also yield an abnormal ischemic forearm test and must be demonstrated histochemically and biochemically. Apart from muscular signs, myopathy with lactic acidosis is associated with palpitation, dyspnea and exhaustion, and a disproportionate rise in serum lactic acid level after exertion. Histochemically and electronmicroscopically demonstrable fat accumulation in the muscle can be a sign of a disturbance in lipid metabolism. This type of exercise-induced myopathy has been reported only in a few cases with carnitine-pylmityltransferase deficiency, which has to be demonstrated biochemically. Muscular contractures also exercise-induced but painless and reversible within seconds may be due to deficient uptake of sarcoplasmic calcium in the tubular system. Dyskalemic paralysis causes painless paresis within minutes of hours after exertion, which disappears within hours to a few days. Myopathy with tubular aggregates can be differentiated from other exercise-induced myopathies by morphology. Myotonia combined with painful contractures characterizes myopathia myotonica.
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PMID:[Exercise-induced muscular weakness, myalgia and contractures. I. A clinical review]. 13 80

A patient with McArdle's disease is reported in whome proximal muscle weakness began in the 7th decade. Other unusual features included the absence of muscle cramps at any stage, asymmetrical wasting of the shoulder girdle muscles and calf hypertrophy. Muscle biopsy revealed a vacuolar myopathy, absent phosphorylase staining and qualitatively low glycogen content.
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PMID:McArdle's disease--what limit to the age of onset? 27 90

Five patients, 4 men and 1 woman, had adult-onset and slowly progressive weakness. There was distal wasting in 2, hepatomegaly in 3, and congestive heart failure in 2. Electromyography showed a mixed pattern with abundant fibrillations. Serum creatine phosphokinase was increased 5- to 45-fold. Blood glucose failed to respond to epinephrine or glucagon, and venous lactate did not rise after ischemic exercise. Muscle biopsy showed vacuolar myopathy affecting both fiber types. By electron microscopy the vacuoles corresponded to large pools of glycogen not limited by a membrane. Glycogen concentration was 3 to 5 times normal in muscle and 7 to 21 times normal in erythrocytes. In the presence of iodine, muscle glycogen showed a spectrum characteristic of phosphorylase-limit-dextrin. Debrancher activity was measured by a spectrophotometric assay and by a radioactive reverse reaction. The activity was lacking in muscle and erythrocytes of 4 patients according to both assays; in 1 patient the reverse reaction was not impaired. Though previously reported in only 5 patients, debrancher deficiency myopathy may not be rare and should be considered in the differential diagnosis of adult-onset hereditary myopathies.
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PMID:Debrancher deficiency: neuromuscular disorder in 5 adults. 28 18

A prolonged glucose load was administered to four patients with hypokalaemic periodic paralysis and four healthy control sujbects. Muscle ATP and CP concentrations as well as lactate dehydrogenase, hexokinase and phosphorylase activities were similar in those two groups, but succinate dehydrogenase was approximately 50% higher in the control muscles. Muscles fibre composition was almost identical in the two groups, whereas patients had a higher degree of capillarization. Complete muscle weakness was produced in all patients, accompanied by hypokalaemia. Glucose loading resulted in elevated insulin levels and a minor rise in blood glucose level was seen in the patients compared to the control subjects. Glucose loading decreased hexokinase activity in controls, but increased this in the patients. At similar times, muscle and blood lactate levels and blood pyruvate values were generally higher in the patients over the course of the experiment. Initial glycogen concentrations were higher in patients, but glucose loading did not result in greatly increased glycogen values. These data suggest that patients with hypokalaemic periodic paralysis have an enhanced metabolism of carbohydrates and that insulin seems to be an important factor leading to the onset of muscle weakness.
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PMID:Skeletal muscle characteristics and carbohydrate metabolism after glucose loading in hypokalaemic periodic paralysis. 70 37

Two sisters with exercise-induced myalgias, muscular weakness and contractures are reported. Neurologic and psychiatric findings were normal, nor did electromyography, serum enzymes and ischemic forearm exercise test reveal specific findings. Under the light microscope multiple muscle fibers contained small vacuoles which stained positive with Oil Red O. No further information resulted from histochemical examinations. In the more seriously affected patient morphometric analysis of electronmicrographs showed a tenfold increase of fat content in comparison to normal controls. Alterations in the enzymatic activities could be demonstrated in glycogenolysis, glycolysis and in fat metabolism, but there were no previously described enzyme defects such as phosphorylase deficiency, phosphofructokinase deficiency, phosphohexoisomerase inhibitor, carnitine or carnitine-palmityltransferase deficiency. Myopathy with lactic acidosis, prolonged muscular relaxation due to deficient reabsorption of sarcoplasmic calcium in the tubular system and dyskalemic paralysis can be ruled out on the basis of the clinical signs. This myopathy may be due to an as yet unknown metabolic disturbances.
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PMID:[Exercise-induced muscular weakness, myalgia and contractures. II. Casuistic contribution]. 84 45

A sporadic case of central core disease in a 5 1/2-year-old girl is reported. Clinically, a retarded motor development existed, furthermore, a muscle weakness and hypotonia of the extremities and trunk, contractures of the hip- and knee-joint,and luxation of both hip-joints. Biopsy specimens are taken from both Mm. gastrocnemii. Muscle fibres show, by morphologic examination, 95 per cent cores, which are characteristic for this myopathy. A further abnormality is seen inthe histochemical preparations for phosphorylase, succinate dehydrogenase, NAD diaphorase tetrazolium reductase, myofibrillar ATPase as well as AS-reaction with and without diastase digestion. With these techniques the muscle fibres show an uniform reaction pattern in which the activities of the oxidative andglycolytic enzymes correspond to the type I fibres of healthy persons. The cores show a lack of a activity of the oxidative and glycolytic enzymes as well as are ATPase- and PAS-negative. By reason of this histochemical behaviour it is suggested that the cores are predominantly unstructured. The cause of this disease might be complex disturbances in the neuro-muscular system manifested in the fetal period.
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PMID:[A case of central core disease. Light microscopic and histochemical studies (author's transl)]. 84 74

A 16-year-old boy with a two-year history of recurrent attacks of myalgia, muscle cramps without weakness, and myoglobinuria was shown to have a deficiency in muscle carnitine palmityltransferase. Serum concentrations of creatinine phosphokinase, serum glutamic oxalacetic transaminase, and aldolase were elevated. An electromyogram was consistent with a nonspecific myopathy as were microscopic and ultrastructural examinations of biopsied muscle. Venous lactic acid response to ischemic exercise was compatible with paroxysmal idiopathic myoglobinuria. Activities of muscle phosphorylase A and B, phosphofructokinase, muscle palmityl CoA synthetase, carnitine, and serum carnitine were normal as was the glycogen content. Activity of muscle carnitine palmityltransferase (2.7 microM/minute/mg protein), as measured by a spectrophotometric method and by radioactive assay, was significantly reduced when compared to normal control subjects (14.5 microM/minute/mg protein) and ischemic control subjects (13.8 microM/minute/mg protein). Muscle carnitine acetyltransferase (13.4 microM/minute/mg protein) was approximately 50% of normal control values (25.5 microM/minute/mg protein). This is the third reported case of myoglobinuria in a patient associated with a deficiency of muscle carnitine palmityltransferase activity.
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PMID:Recurrent myoglobinuria and muscle carnitine palmityltransferase deficiency. 87 82


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