摘要:

AbstractClinical and laboratory data of five cases of Emery—Dreifuss muscular dystrophy in three generations of a family are reported. Severity of the myopathic picture varied in the five patients considerably from almost noninvolvement to severe manifestations. In contrast, cardiomyopathy was severe not only in three adults but also in a 13‐year‐old boy. A review is given of 73 cases from the 6 major families reported in the literature. Most striking is the high incidence of sudden death. A wide variability in the severity of the myopathic picture was also ev

ISSN:0148-639X    

DOI:10.1002/mus.880090602

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

年代:1986

数据来源: WILEY

摘要:

AbstractWe have defined three new features of the electromyographic (EMG) interference pattern (IP): activity, upper centile amplitude (UCA), and number of small segments (NSS). These parameters were measured in simulated IPs constructed by adding together motor unit action potentials (MUAPs) recorded with a concentric needle EMG electrode. The activity increases linearly with the number of MUAP discharges to approximately 80% of its theoretical maximum value. The UCA correlates strongly with the peak‐to‐peak amplitude of the largest MUAP in the IP and the mean segment amplitude and does not depend on the discharge rate of the largest MUAPs. We infer that the UCA defines the upper limit of the peak‐to‐peak amplitude of the MUAPs contained in the IP. The NSS increases with the number of MUAP discharges, but reaches a constant value at higher MUAP discharge rates, probably because small amplitude MUAPs are masked by the large amplitude MUAPs. The potential value of these parameters in automated IP analysis is di

ISSN:0148-639X    

DOI:10.1002/mus.880090603

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

年代:1986

数据来源: WILEY

摘要:

AbstractThe electromyographic (EMG) interference pattern (IP) was measured in the biceps muscle of 16 normal male and 17 normal female subjects. The activity, upper centile amplitude (UCA), and the number of small segments (NSS) (defined in a companion paper) were measured from 500‐msec epochs of the IP. The normal values of these features were defined separately for men and women by plotting the UCA and NSS values against activity for each epoch and defining an area on these plots, called a “cloud,” that contained more than 90% of the datum points from each study. The mean deviation of the individual datum points from the overall mean values was also calculated for each study. A study in one muscle is considered to be normal if more than 90% of the datum points from that muscle are within the normal clouds and the deviation values are within their normal range. In patients with neuropathy, the characteristic pattern was increased UCA with normal or decreased NSS. In patients with myopathy, NSS was increased and the UCA was normal or decreased. In all studies, the interpretations of the IP from the plots agreed with qualitative assessments of the IP made independently by an electromyographer. The use of these features to understand and quantitate the changes in the motor units produced by disease is demonstrated by serial studies performed in a patient with motor neuron di

ISSN:0148-639X    

DOI:10.1002/mus.880090604

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

年代:1986

数据来源: WILEY

摘要:

AbstractMuscular dystrophy induces extensive changes in the patterning of sarcolemmal caveolae of fast‐twitch fibers from the chicken posterior latissimus dorsi (PLD) muscle, which in healthy fibers are arranged in striking bands over the myofibrillar I‐bands. In dystrophic fibers the caveolae lack this patterned arrangement, and instead are dispersed over the entire sarcolemma, are irregular in shape, and are more numerous in older birds. Quantitative analysis of these differences provides three independent numerical indices of the dystrophic state and suggests that constraints responsible for normal patterning are lost in diseased fibers. These observations support theories that defects of the muscle plasma membrane are important for dystrophic pathogenesis in contrast, the sarcolemma of slow tonic fibers from anterior latissimus dorsi (ALD) and metapatagialis latissimus dorsi (MLD) muscles have randomly dispersed caveolae whose appearance and distribution are unaffected by the dise

ISSN:0148-639X    

DOI:10.1002/mus.880090605

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

年代:1986

数据来源: WILEY

摘要:

AbstractAn in vitro system for the combined biochemical and physiologic analysis of striated muscle has been developed. It is hoped that its eventual application will be to the evaluation of human muscle disease. To test the method's usefulness in evaluating metabolic defects, we used iodoacetate to induce a glycolytic defect in animal muscle. This produced the expected effects of precipitous fatigue on repetitive stimulation, increased inosine monophosphate (IMP) and decreased adenosine triphosphate (ATP) and phosphocreatine; in addition, the severity of the glycolytic block was directly related to the amount of IMP produced per gram twitch tension.

ISSN:0148-639X    

DOI:10.1002/mus.880090606

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

年代:1986

数据来源: WILEY

摘要:

AbstractA patient with the Lambert‐Eaton syndrome (LES) and small cell lung cancer developed respiratory failure several hours after verapamil was given. Improvement in respiratory function did not occur when guanidine was given, but was delayed until verapamil was discontinued 3 days later. Although other factors may have contributed to the clinical deterioration of our patient, the temporal relationship to verapamil and the theoretical danger of calcium channel blockade lead us to believe that the drug should be used cautiously in LE

ISSN:0148-639X    

DOI:10.1002/mus.880090607

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

年代:1986

数据来源: WILEY

摘要:

AbstractPurified IgG antibodies were prepared by ion‐exchange chromatography from the plasma of a patient with nonneoplastic form of the Lambert‐Eaton myasthenic syndrome (LES). The antibodies were injected into mice with daily doses of 0.15–10 mg for 20–22 days, following which the integrity of neuromuscular transmission was assessed in vitro in phrenic nerve‐diaphragm muscle preparations. The injected animals manifested electrophysiologic features of human LES, which were characterized by: (1) dose‐dependent reduction in the quantal content of nerve‐evoked endplate potentials, (2) an abnormally small increase in the frequency of spontaneous miniature endplate potentials (MEPPs) with elevated [K+]0, and (3) normal MEPP amplitude with no evidence of postjunctional deficiency. Crude immunoglobulins (Igs) from the same patient and two LES patients with associated malignancy similarly transferred the defects in quantal transmitter release. In contrast, animals receiving Igs from control subjects or from a patient with small‐cell carcinoma of the lung manifested no functional impairment of neuromuscular transmission. Instead, the evoked release in these animals was significantly enhanced relative to that found in normal untreated mice. These results suggest that an IgG antibody produces the presynaptic impairment that is characteristic of LES and support the concept that LES with and without cancer has an autoimmu

ISSN:0148-639X    

DOI:10.1002/mus.880090608

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

年代:1986

数据来源: WILEY

摘要:

AbstractCronassial, a combination of four different cerebral gangliosides, was administered intramuscularly (40 mg daily) in a double‐blind controlled study of 28 patients with moderate to severe diabetic neuropathy. Clinical neurologic and near‐nerve electrophysiologic studies were performed. The 14 patients receiving gangliosides experienced statistically significant improvement in their clinical scores due to an increase in lower extremity sensory perception. No other clinical or electrophysiologic changes were present. No side effects were noted. Further studies employing greater numbers of patients and higher doses are required to confirm the efficacy of gangliosides in diabetic neuropa

ISSN:0148-639X    

DOI:10.1002/mus.880090609

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

年代:1986

数据来源: WILEY

摘要:

AbstractIn Japanese quails with late‐onset acid maltase deficiency (AMD), the activity of acid α‐glucosidase was severely reduced to approximately 16% of the normal level from an embryonic age. The kinetic characteristics and inhibition by Zn indicated that the residual activity was responsible for the intrinsic activity of acid α‐glucosidase. However, in affected embryos, the glycogen content and other lysosomal enzyme activities were normal, despite the low acid α‐glucosidase activity. In a separate study, we found the existence of two age‐dependent neutral α‐glucosidases— “embryonic” and “adult” α‐glucosidases. In affected quails, the transition from the embryonic neutral α‐glucosidase to the adult type was not influenced by the disease. The activity toward maltose and glycogen of the embryonic neutral α‐glucosidase may explain the normal glycog

ISSN:0148-639X    

DOI:10.1002/mus.880090610

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

年代:1986

数据来源: WILEY

摘要:

AbstractThe utilization of so‐called standard muscles for biopsy in patients with the clinical features of facioscapulohumeral muscular dystrophy (FSH) often results in nondiagnostic pathologic findings. Five patients are presented who had biopsies of the supraspinatus muscle in addition to one of the standard muscles. The supraspinatus muscle was diagnostic in all five cases. The findings suggest that the supraspinatus muscle should be considered as the biopsy site of first choice in those patients in whom the clinical picture suggests facioscapulohumeral‐type muscular dystro

ISSN:0148-639X    

DOI:10.1002/mus.880090611

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

年代:1986

数据来源: WILEY