摘要:

AbstractA new EMG recording technique called macro EMG is described. The recording electrode is the cannula of the modified single fiber electromyography (SFEMG) electrode. By means of spike triggered averaging, the contribution from all muscle fibers in a motor unit is extracted. The resulting signal reflects the number and size of muscle fibers in one motor unit. This paper presents the details of the technique, the neurophysiological basis for generation of the macro EMG signal, and the typical findings in normal and diseased muscles. Finally, examples are given of the additional information that can be obtained by combining investigations with SFEMG, conventional EMG, and macro EMG in the same muscles.

ISSN:0148-639X    

DOI:10.1002/mus.880060902

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractAxonal swellings associated with large aggregates of neurofilaments are characteristic of neuropathies caused by chemical neurotoxins (nhexane, methyl n‐butyl ketone, and acrylamide) or giant axonal neuropathy (GAN—an autosomal recessive genetic disease). In GAN, filamentous aggregates have been shown also to occur in other cell types including cultured skin fibroblasts. Therefore, we studied the effects of 2,5‐hexanedione (the neurotoxic metabolite of n‐hexane and methyl n‐butyl ketone) and acrylamide on normal human skin fibroblasts in tissue culture. We show that both neurotoxins induce aggregation of intermediate, filaments of the vimentin type in the cultured fibroblasts without disrupting mic

ISSN:0148-639X    

DOI:10.1002/mus.880060903

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractAcetylcholinesterase (AChE) was extracted from normal and dystrophic C57BL/6J mouse hindlimb muscles and its molecular forms fractionated by sucrose density gradient ultracentrifugation. In the soleus muscles from 6‐ to 7‐week‐old mice an increase in the 3 Svedberg unit (S) and a decrease in the 16S AChE molecular forms was observed in dystrophic animals compared to controls. At 12–13 weeks of age, no major significant differences in the relative proportions of AChE molecular forms were noted. In the extensor digiorum longus (EDL) muscles of 6‐ to 7‐week‐old dystrophic mice a significant decrease in the proportion of the 10S AChE molecular form and an increase in the 3S and 5S forms was observed. At 12–13 weeks, the dystrophic EDL muscles again displayed a decrease in the 10S form; however, the increase in the 3S and 5S AChE forms, while still apparent, was not significant. These results provide evidence for a biochemical abnormality in the distribution of specific AChE molecular forms, and a differential expression of this abnormality in the soleus

ISSN:0148-639X    

DOI:10.1002/mus.880060904

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractCylindrical spirals are abnormal uniform membranous inclusions in skeletal muscle, usually confined to type 2 fibers. Hitherto, only five cases have been published with various clinical syndromes. Here, a case is presented for the first time with detailed electrophysiological, histometrical, and biochemical analysis: a 60‐year‐old man with slowly progressing polyneuropathy confirmed by electrophysiological findings, and a history of diabetes, alcoholism, nicotine abuse, and weight reduction. In various muscle biopsies, large aggregates of cylindrical spirals were found almost exclusively in type 2B fibers. Obviously, the aggregates were derived from abnormal perinuclear and, therefore, mainly subsarcolemmal tubulovesicular structures. Morphometrical, histochemical, and biochemical analysis of muscle revealed no further information about the nature of these inclusions. They were not present in skin biopsy containing subcutaneous ner

ISSN:0148-639X    

DOI:10.1002/mus.880060905

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractD‐Penicillamine added to lymphocyte cultures from myasthenia gravis patients infrequently and inconsistently stimulated anti‐AChR production. This usually occurred in the presence of pokeweed mitogen (PWM), and often only at a single concentration ofD‐penicillamine which varied among patients. The change was typically paralleled by an increase in total IgG production of similar magnitude, suggesting that the effect was nonspecific.D‐penicillamine did not affect AChR expression in cultured thymic adherent cells. These data provide no evidence that penicillamine induces myasthenia gravis by direct stimulation of anti‐AChR antibody‐prod

ISSN:0148-639X    

DOI:10.1002/mus.880060906

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractWe have localized β‐enolase activity in human skeletal muscle fiber using the immunohistochemical method (two‐step method). The first immunoreagent was rabbit anti‐human β‐enolase serum raised in New Zealand white rabbit, and the second was peroxidase conjugated staphylococcal protein A. The immunohistochemical reaction for β‐enolase was noted higher in type 2 fiber, which demonstrates the low oxidative and high glycolytic enzyme activity, than in

ISSN:0148-639X    

DOI:10.1002/mus.880060907

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractTarsal tunnel syndrome is relatively rare and the diagnosis may be difficult even though the etiologies for the syndrome are multiple. The symptoms are often vague but are usually burning pain and paresthesias in the toes and soles of the feet with nocturnal exacerbations. The physical examination may elicit a sensory deficit over the cutaneous distribution of the median and/or lateral plantar nerve. There may also be tenderness over the flexor retinaculum. Electrodiagnosis, especially with the addition of the orthodromic compound nerve action potential latency technique, is essential to confirm the diagnosis. The findings may be confined to the distribution of either the medial or lateral plantar nerves and, thus, both distal latencies must be determined. Surgical decompression of the tarsal tunnel has usually proven to be helpful in those patients who do not respond to conservative treatment.

ISSN:0148-639X    

DOI:10.1002/mus.880060908

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractThe possibility that some features of Duchenne muscular dystrophy (DMD) can be explained as a disturbance of nerve‐muscle interaction during development is discussed. It is argued that the initial disturbance in DMD is due to a slower rate of maturation of skeletal muscle fibers. Normally, the maturation of the motor reflexes is closely followed by maturation of the muscle fibers. The possibility is considered that if muscle fibers mature more slowly than normal, they are not able to withstand the type of activity imposed upon them by the mature motoneuron. This applies mainly to the high frequency activity imposed on the fibers of motor units that are destined to become “fast.” Experimental evidence suggesting such a mechanism is pres

ISSN:0148-639X    

DOI:10.1002/mus.880060909

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractOver 1,000 needle biopsies have been carried out at University College Hospital in London. Needle biopsy has been used by us for histochemical and electron microscopic examination of muscle during the diagnosis and treatment of neuropathic and myopathic disorders, for the diagnosis of mitochondrial myopathies, to study the course of recovery in polymyositis, and for investigations into muscle changes in systemic lupus erythematosus (SLE) and other autoimmune conditions. We have developed a microprocessor system for the measurement of muscle fiber areas, and needle biopsy specimens provide suitable material for such measurements. We have also used needle biopsy specimens for studies of protein turnover using stable isotopes and for trace metal and electrolyte analyses. Needle biopsy is safe and rapid. As the patient usually experiences only minimal discomfort and thereis no permanent scar, repeat biopsies are well tolerated allowing follow‐up studies after treatmen

ISSN:0148-639X    

DOI:10.1002/mus.880060910

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

ISSN:0148-639X    

DOI:10.1002/mus.880060911

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY