摘要:

AbstractA follow‐up study of muscle strength, muscle morphology, and enzymatic activity in 23 men, 73–83 years of age, was performed 7 years after the first investigation. With the exception of two men treated for congestive heart failure and four treated for hypertension, all were apparently clinically healthy and none had functional locomotor disturbances. Body weight was reduced by 2% and body cell mass by 6%, whereas the quadriceps muscle strength decreased 10%–22% over the 7‐year period. Fiber composition in the vastus lateralis did not change significantly, and there was no significant difference between the biopsies from the biceps brachii and vastus lateralis. In the vastus lateralis, there was a reduction in fast‐twitch fiber areas, which were smaller than in the biceps brachii (not studied at the previous investigation). There were also more histopathologic changes in the vastus lateralis than in the biceps brachii. The enzymatic activities of lactate dehydrogenase and myokinase, which were studied on both occasions in the vastus lateralis, did not change, and the activities of the other measured enzymes indicated a maintained metabolic capacity at high age. Oxidative enzymatic activities were higher in the vastus lateralis, and glycolytic enzymatic activities were higher in the biceps brachii, which could partly be explained by differences in relative fi

ISSN:0148-639X    

DOI:10.1002/mus.880090702

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

年代:1986

数据来源: WILEY

摘要:

AbstractWe measured distal sympathetic and vagal function in 73 consecutive patients with diabetic neuropathy seen at the Mayo Autonomic Reflex Laboratory. Postganglionic sympathetic failure measured proximally within the foot occurred as commonly as vagal failure (58% and 55%, respectively) and‐occurred much more frequently than did orthostatic hypotension (26%). Either vagal or distal sympathetic abnormalities occurred in isolation in about one in six patients with diabetic neuropathy. We conclude that distal sympathetic failure and vagal failure occur with equal frequency when sensitive and quantitative recording methods are used and that it is advantageous to test both systems, as only one may be involved in some patient

ISSN:0148-639X    

DOI:10.1002/mus.880090703

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

年代:1986

数据来源: WILEY

摘要:

AbstractNormal and dystrophic hamster myoblasts and fibroblasts were compared for characteristic indicators of growth and differentiation. Clonal analysis of myoblast cultures indicated that 80% of colonies judged to be fusion‐competent had differentiated. Dystrophic myoblasts were identical to normal in terms of their morphology, fusion potential (81.4%), and myokinase activity (59.6–49.1 mU/mg at 2–7 days), but displayed a significantly higher plating efficiency (normal: 52.6%; dystrophic: 82.1%), a longer doubling time (normal: 21.7 hours; dystrophic: 33.3 hours), and a lower day‐7 creatine kinase activity (normal: 60.7 mU/mg; dystrophic: 41.3 mU/mg). Dystrophic fibroblasts were indistinguishable from normal ones in terms of their morphology, plating efficiency (90.4%), and doubling time (32.5 hours), but displayed a significantly lower day‐2 creatine kinase activity (normal 58.3 mU/mg; dystrophic: 35.8 mU/mg) and day‐7 myokinase activity (normal: 52.7 mU/mg; dystrophic: 39.9 mU/mg). The results are suggestive of an early and differential expression of the primary defect in dystrophic hamster myoblasts and fibroblasts

ISSN:0148-639X    

DOI:10.1002/mus.880090704

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

年代:1986

数据来源: WILEY

摘要:

AbstractDisorders of neuromuscular transmission in infants and children can be divided into two groups. The first group includes conditions similar to those seen in adults: autoimmune myasthenia gravis, Lambert‐Eaton myasthenic syndrome, and botulism. The second includes several disorders that are unique to this age group, such as the congenital myasthenias and infantile botulism. This review discusses the diseases of neuromuscular transmission found in the pediatric population, with emphasis on electrodiagnosis. The distinctive clinical and electrophysiologic features allow the clinician to identify these illnesses correctly, so that appropriate treatment can be instituted or further specialized investigation can be undertake

ISSN:0148-639X    

DOI:10.1002/mus.880090705

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

年代:1986

数据来源: WILEY

摘要:

AbstractNine patients with complete denervation of the tibialis anterior were admitted to a stimulation program in order to restore dorsiflexion of the foot. Best results were obtained with pulses of 20‐msec pulse width and 20‐msec interval. After 3 weeks of training for 2 × 20 min/day, dorsiflexion due to stimulation was increased in all patients. In some of them, gait could be improved during the swing phase using electrical stimulation. The applied training program thus reversed the course of disuse atrophy and proved the feasibility of functional electrical stimulation for patients with denervated mus

ISSN:0148-639X    

DOI:10.1002/mus.880090706

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

年代:1986

数据来源: WILEY

摘要:

AbstractAn apparently inherited myopathy, characterized by the presence of large numbers of nemaline rods in skeletal muscle fibers, was investigated in five cats. Onset of signs varied from 6 months to 1.5 years of age and consisted of reluctance to move, jerky gait and muscle twitching, hyporeflexia, and muscle wasting, which was most prominent in the proximal muscles of the forelimbs. All of the cats, three males and two females, were from the same dam. In addition to the presence of rods, the myopathy was characterized by marked fiber size variation, with atrophy of type 1 and type 2a muscle fibers. In addition, there was infolding of the sarcolemma and fiber splitting. Ultrastructurally, the rods closely resembled those described in human nemaline myopathy.

ISSN:0148-639X    

DOI:10.1002/mus.880090707

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

年代:1986

数据来源: WILEY

摘要:

AbstractA patient with severe subacute sensory ataxia was found to have an IgM (kappa) cryoglobulin. Clinical, electrophysiologic, and sural nerve biopsy studies indicated that axonal degeneration and segmental demyelination both played a role in the pathogensis of this neuropathy. Corticosteroid therapy was associated with notable clinical improvement and a 50% decrease in cryoglobulin concentration.

ISSN:0148-639X    

DOI:10.1002/mus.880090708

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

年代:1986

数据来源: WILEY

摘要:

AbstractWe are reporting five patients who suffered serious injuries from surgery for thoracic outlet syndrome, which has been a controversial subject from many aspects. Many argue that it is much overdiagnosed and overtreated. The term „disputed thoracic outlet syndrome”︁ has recently been applied to the majority of cases in which there are little or no clinical findings. The much more rare true neurogenic thoracic outlet syndrome does have associated neurologic and electrical findings. Recently, the use and misuse of electrodiagnostic studies in the diagnosis of disputed thoracic outlet syndrome has been discussed in the literature. The cases that we are reporting are especially tragic because the elective surgeries were performed in patients who had little or no clinical abnormalities on examination prior to the su

ISSN:0148-639X    

DOI:10.1002/mus.880090709

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

年代:1986

数据来源: WILEY

摘要:

AbstractEleven patients, comprising three cases of McArdle's disease and eight with an exertional muscle pain syndrome (EMPS) of unknown cause, entered a double‐blind crossover study of verapamil and placebo. None of the patients with McArdle's disease responded to verapamil, but two patients with unclassified EMPS experienced a striking improvement in symptoms and two others showed a partial response. No patient responded to placebo. Six of the eight cases with unclassified EMPS, including the four patients who responded to verapamil, had symptoms that indicated possible abnormalities of muscle metabolism, and four showed nonspecific biochemical, electromyographic, and muscle biopsy abnormalities. The two other EMPS patients had symptoms that suggested that a primary muscle disease was unlikely. They showed no laboratory evidence of muscle disorder, but had abnormal profiles on personality (MMPI) testing. Calcium antagonists, such as verapamil, may be useful in the treatment of some patients with benign exertional myalgia, but the mechanism of action of the drug in such cases is unclea

ISSN:0148-639X    

DOI:10.1002/mus.880090710

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

年代:1986

数据来源: WILEY

摘要:

AbstractIn this study, the relative endplate position of fibers of rat gastrocnemius caput mediale (GM) muscle was determined by counting numbers of sarcomeres. Isolated fibers were teased from the proximal, intermediate, and distal regions of the muscle. Endplates of distal fibers were located on the proximal third of their lengths. Endplates of intermediate fibers were located at half fiber length, and for proximal fibers, a variable endplate position was obtained: in half of the muscles studied, endplates occurred around the proximal one‐third and in the other half near the midpoint of the fiber. Endplate position relative to fiber length was thus found to be dependent on the region of the muscle. Changes in the orientation of endplate zone relative to the muscle belly is likely to take place with changes in muscle length, as shown by a planimetric muscle model. It is argued that architecture of pennate muscles may highly affect characteristics of motor unit potential

ISSN:0148-639X    

DOI:10.1002/mus.880090711

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

年代:1986

数据来源: WILEY