Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0026850 (muscular dystrophy)
 5,870 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Electromyographic and histopathological studies were performed on 112 skeletal muscles in 101 subjects with myopathy. The diagnostic significance of large action potentials (LAPs) in myopathy was studied. LAPs were defined as those action potentials with a duration of over 13 ms and an amplitude of over 3 mV (peak to peak). The following results were obtained: Most muscles with LAPs showed the grouped atrophy of small fibers of neuropathic change in addition to myopathic findings. Even in myopathy most LAPs reflected neuropathic change, except in thyrotoxic myopathy. LAPs were not related to an increase of connective tissue increasing the impedance in volume conduction of the action potentials. LAPs were frequently seen in: progressive muscular dystrophy of limb-girdle type; scapuloperoneal dystrophy; distal myopathy; oculopharyngeal dystrophy; myotonic dystrophy; polymyositis; and thyrotoxic myopathy. Other types of myopathy had few LAPs. There were two types of progressive muscular dystrophy. One had LAPs frequently and the other, rarely. In myotonic dystrophy the muscles with LAPs showed scattered small angular fibers, possibly indicating neurogenic changes. Interstitial myositis had LAPs more frequently than parenchymatous polymyositis. The chronic phase of polymyositis had LAPs more frequently than the acute or subacute phases. In thyrotoxic myopathy the muscles with LAPs rarely showed definite neuropathic change histopathologically. Therefore, LAPs in thyrotoxic myopathy may not indicate denervation.
 ...
PMID:The diagnostic significance of large action potentials in myopathy. 664 25

Myotonic dystrophy is a unique form of muscular dystrophy which is associated with a variety of ocular manifestations. Perhaps the most noteworthy of these is the distinctive myotonic cataract which often appears early on in the course of the disorder. In this report, a seemingly healthy young man who presented for routine visual examination was found to have specific lenticular changes suggestive of myotonic dystrophy. Other signs of this condition, including the myotonic facies, restrictions of ocular motility, and the myotonic handshake, were not readily apparent. Although visual acuity was not dramatically impaired, the unusual nature of the lens opacities, and in particular the presence of brilliant polychromatic particles, called for a neurologic consultation which promptly confirmed the diagnosis.
 ...
PMID:Cataracts in myotonic dystrophy. 665 88

The regenerative ability of muscles was studied in various neuromuscular disorders by quantitative electron microscopy using two indices of both the satellite cell population and the euchromatin percentage of satellite cell nucleus. Both the number of satellite cells and the euchromatin percentage were increased in polymyositis. Duchenne muscular dystrophy and myotonic dystrophy showed only an increased number of satellite cells without increased euchromatin percentage, while amyotrophic lateral sclerosis had only an increased euchromatin percentage without increased satellite cell number. These results suggest that some defects of satellite cell function probably exist in progressive muscular dystrophy and amyotrophic lateral sclerosis, while in polymyositis the muscle fiber may have the ability to regenerate completely. The euchromatin percentages of myonuclei were increased in polymyositis and Duchenne muscular dystrophy, but not in amyotrophic lateral sclerosis or myotonic dystrophy compared to those of controls. This suggests the activated function of the remaining muscle fibers in polymyositis and Duchenne muscular dystrophy.
 ...
PMID:A quantitative study of the muscle satellite cells in various neuromuscular disorders. 666 77

Using radionuclide angiocardiography, we studied cardiac function in 10 men with myotonic muscular dystrophy who had no cardiac symptoms and were less than 50 years of age, comparing resting and exercise performance of the heart. Nine of 10 patients had an abnormality of myocardial function. The interaction of exercise-induced cardiomyopathy with conduction system abnormalities may be important in sudden cardiac dysfunction in patients with myotonic dystrophy.
 ...
PMID:Radionuclide angiocardiographic analysis of myocardial function in myotonic muscular dystrophy. 668 7

This report deals with morphometric investigations of muscle biopsies using a semiautomatic manual analysis system. Examples for differential diagnostic value of metric results are described: 1) Different distribution curves of muscle fibers are helpful in differentiating between two important groups of muscle diseases, chronic polymyositis and muscular dystrophy. 2) Some groups of disorders (e.g. interstitial myositis, neurogenic atrophy) may be subtyped by metric data. 3) Several diseases (e.g. myotonic dystrophy) are characterized by selective atrophy of one fiber type only in distinct muscle groups.
 ...
PMID:[Value of myometric findings in the morphological differential diagnosis of neuromuscular disorders (author's transl)]. 693 Dec 79

Insulin insensitivity of uncertain etiology often exists in myotonic muscular dystrophy, a multitissue, autosomal dominant disorder hypothesized to be a hereditary membrane disease. The present studies show that monocytes from patients with myotonic dystrophy fail to demonstrate the normally observed qualitative increase in insulin-binding affinity after oral glucose loading. Monocytes from 10 normal volunteers developed a significantly increased insulin-binding affinity by 2 hr after glucose ingestion (mean +/- SEM, 11.7 +/- 2.7 ng/ml compared to basal 50% insulin displacement value of 23.3 +/- 2.2 ng/ml, P less than 0.005). This increase was maintained at 5 hr (13.5 +/- 2.7 ng/ml, P less than 0.05). In contrast, no significant increase in monocyte insulin-binding affinity occurred in cells from nine myotonic dystrophy patients at 2 and 5 hr after glucose loading (50% insulin displacement values: basal, 14.2 +/- 2.8 ng/ml; 2 hr, 16.7 +/- 1.7 ng/ml; 5 hr, 10.8 +/- 2.1 ng/ml). These alterations document the presence of abnormalities in the insulin receptor or receptor-associated processes that modulate insulin binding. A hereditary plasma membrane defect may underlie these findings. This abnormality may have an etiologic role in the decreased insulin sensitivity that frequently afflicts patients with myotonic dystrophy.
 ...
PMID:Abnormal regulation of monocyte insulin-binding affinity after glucose ingestion in patients with myotonic dystrophy. 701 35

Proximal spinal muscular atrophy (Kugelberg-Welander syndrome) is a degenerating disease of the anterior horn cells of the spinal cord with atrophy of the proximal muscles resembling muscular dystrophy. The patient in this report exhibits radiographic features in the gastrointestinal tract similar to those seen in the muscular dystrophies, including myotonic dystrophy.
 ...
PMID:Gastrointestinal radiologic manifestations of proximal spinal muscular atrophy (Kugelberg-Welander syndrome). 712 Apr 81

Biopsy material from the vocal muscle of patients suffering from Steinert's muscular dystrophy, Duchenne's muscular dystrophy, oculopharyngeal progressive muscular dystrophy, and paraneoplastic myopathy was examined under the light and electron microscope. The histological findings were compatible with the muscular changes seen in the skeletal muscles of the extremities of the same patients. Slight differences in the severity of the pathologic process were noticed in correlation with the muscles of the extremities which were always more seriously affected than the vocal muscles. The ultrastructural study revealed a moderate to very permanent dilatation of the sarcotubular system, involving the T-tubules and the cisternae of the smooth endoplasmic reticulum as well. From the clinical point of view, the vocal muscle biopsy was beneficial to the patients suffering from Steinert's myotonic muscular dystrophy, whereas it did not affect the clinical condition of the others.
 ...
PMID:Histological and ultrastructural findings in the vocal muscles of patients suffering from muscular dystrophies. 729 78

Respiratory impairment in patients with Steinert's muscular dystrophy is known to lead to respiratory failure. Both the blunted chemical drive of breathing and the respiratory muscle weakness have been cited in the pathophysiology of premature death in these patients. To further assess the chemical control of breathing in these patients, we measured their respiratory responses to hypoxia (Weil's method), hyperoxia (Dejours' method), and hypercapnia (Read's method). In response to the stimuli from these respiratory centers, minute ventilation (VE), tidal volume (VT), respiratory frequency (F), mean inspiratory flow rate (VT/Ti), and occlusion pressure (P0.1) were measured in 12 patients and in 12 normal persons matched to the patients on the basis of age, sex, and arm span. The patients were similar to the control subjects in occlusion pressure results. However, they differed significantly (P less than 0.01) in ventilatory responses by a lower VE, lower VT, higher F, and lower VT/Ti in response to the hypercapnia and hypoxia tests. The responses of patients and control subjects were similar during the hyperoxia tests. Our study, therefore, established that the chemosensitivity of the respiratory centers, as measured by P0.1, is well preserved in Steinert's myotonic dystrophy, but the output to breathing (VE, VT, F, VT/Ti) is modulated by the impaired respiratory mechanics causing a tachypneic breathing pattern, even in the absence of restricted lung volume.
 ...
PMID:Control and modulation of respiration in Steinert's myotonic dystrophy. 736 35

Volume selective proton magnetic resonance spectroscopy of brain was performed on a 1.5 T magnet in 5 patients with congenital muscular dystrophy and compared to the results in 46 healthy children and 1 healthy adult. Peaks of N-acetyl aspartate, choline, and creatine but not lactate, were observed in both groups on proton magnetic resonance spectroscopy. Spectroscopy of controls revealed an increase with advancing age in the ratio of N-acetyl aspartate/choline and N-acetyl aspartate/creatine and a decrease in the choline/creatine ratio. In patients with congenital myotonic dystrophy, the N-acetyl aspartate/choline ratio did not increase with advancing age, but the N-acetyl aspartate/creatine ratio did. The choline/creatine ratio decreased with advancing age, which matched the results of controls. At any age older than 4 years, the N-acetyl aspartate/choline and N-acetyl aspartate/creatine ratios were lower in patients with congenital myotonic dystrophy than in controls. The choline/creatine ratio did not differ between congenital myotonic dystrophy and controls. These results suggest that in patients with congenital myotonic dystrophy N-acetyl aspartate decreases and there exists a developmental disorder of neurons in brain.
 ...
PMID:Proton magnetic resonance spectroscopy of brain in congenital myotonic dystrophy. 754 6


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>