ISSN:0148-639X    

DOI:10.1002/mus.880130702

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

年代:1990

数据来源: WILEY

摘要:

AbstractOur experience and review of the literature reveal that Sjogren' syndrome (SS) is an important, poorly recognized cause of peripheral neuropathy. Several forms of peripheral nerve dysfunction occur in SS including trigeminal sensory neuropathy, mononeuropathy multiplex, distal sensory neuropathy, distal sensorimotor peripheral neuropathy and a pure sensory neuronopathy syndrome. Rarely, chronic relapsing inflammatory polyneuropathy and multiple cranial neuropathies appear. Clinical evidence of glandular in volvement is often minimal or absent when patients with SS develop peripheral neuropathy; and the diagnosis of the underlying condition is elusive. We review clinical and laboratory features of this disorder and suggest appropriate evaluation of patients with neuropathy and suspected SS.

ISSN:0148-639X    

DOI:10.1002/mus.880130703

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

年代:1990

数据来源: WILEY

摘要:

AbstractThis study was performed to determine whether electrical stimulation can retard denervation‐induced changes. The denervated extensor digitorum longus of the rabbit, a fast‐twitch muscle, was stimulated at a rate mimicking its motoneuron firing pattern. The 100‐Hz stimulation given intermittently ubjected the muscle to a low mean total daily frequency of 1.6 Hz. Four weeks of stimulation resulted in no effect upon the denervated stimulated muscle. This stimulation protocol, therefore, is unable to substitute for the lost neuronal influence of the nerve. The muscle contralateral to the stimulated side showed physiological changes making it unsuitable to serve as a co

ISSN:0148-639X    

DOI:10.1002/mus.880130704

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

年代:1990

数据来源: WILEY

摘要:

AbstractElectrophysiologic studies in 11 patients with Dejerine‐Sottas disease (hereditary motor and sensory neuropathy type III, HMSN II) showed median and ulnar motor nerve conduction velocities less than 6 m/sec in all but 1 patient. Marked temporal dispersion without conduction block was present in all patients. Uniform slowing in adjacent motor nerves was consistent with other studies of inherited neuropathies, although marked temporal dispersion may make HMSN III more difficult to distinguish from acquired neuropathies than other hereditary conditions. The electrophysiologic features of HMSN III patients were significantly different from a series of patients with other hereditary neuropathies chosen because of very slow nerve conduction velocit

ISSN:0148-639X    

DOI:10.1002/mus.880130705

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

年代:1990

数据来源: WILEY

摘要:

AbstractPrevious reports indicated that glucose uptake in denervated muscle is resistant to insulin, while in non‐weight‐bearing (unweighted) muscle this effect of insuling is enhanced. To extend the comparison of these differences, insulin effects on amino acid uptake and protein metabolism were studied in soleus muscles subjected to denervation or unweighting. Denervated muscle showed insulin resistance of both 2‐deoxy[1,2‐3H] glucose and ‐[methyl‐3H]aminoisobutyric acid uptake whereas unweighted muscle showed an increased or normal response, respectively. Atrophy was greater in denervated than in unweighted muscle, apparently due to faster protein degradation by insulin was generally less in denervated than in unweighted muscle, apparently due to faster protein degradation. The stimulation of protein synthesis and the inhibition of protein degradation by insulin was generally less in denervated than in unweighted muscle. Since metabolic measurements in denervated‐unweighted muscles did not differ from those in denervated‐weight‐bearing muscles, effects of denervation must be independe

ISSN:0148-639X    

DOI:10.1002/mus.880130706

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

年代:1990

数据来源: WILEY

摘要:

AbstractEach digital branch of the median nerve was stimulated in turn in 34 women (55 hands) with carpal tunnel syndrome (CTS). The amplitude and conduction velocity of the sensory nerve action potential (SNAP) recorded at the wrist, and the threshold for patient perception of the electrical stimulus on the median innervated sides of each digit, were compared with the corresponding values in a group of asymptomatic, age‐matched women. Sensory conduction velocity of SNAP amplitude were abnormal in more than 80% of all digital nerves studied apart from those in the index finger. Stimulation of digital nerves in the index finger proved the least sensitive means of detecting the electrophysiological abnormality. We conclude that selective digital nerve stimulation is a sensitive technique in the diagnosis of CTS. If ring electrodes are preferred, our results suggest that the middle rather than the index finger should be use

ISSN:0148-639X    

DOI:10.1002/mus.880130707

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

年代:1990

数据来源: WILEY

摘要:

AbstractEnzymes of energy production were measured in muscle homogenates and in individual muscle fibers from 5 patients with McArdle's disease. Individual fibers were investigated to determine whether fibers of all types were completely devoid of glycogen phosphorylase activity and whether the involved fibers might be biochemically altered in a fiber type dependent manner to enhance the energy‐generating capabilities of the cells through other metabolic pathways. Using highly sensitive biochemical assays, a complete absence of glycogen phosphorylase, a and b, activity was found in fibers of all types in the McArdle's patients. Levels of enzymes representing glycolysis, the Krebs cycle, and high energy phosphate metabolism were essentially normal in each fiber type, indicating an apparent lack in metabolic adaptation of these energy pathways to the absence of fatty acids (β‐hydrosyacyl CoA dehydrogenase, βOAC) was elevated in all patients, and substantially in 4 of the 5. This suggested that lipid substrates can provide support for oxidative endurance capacity in some patients. Individual fiber analysises indicated that the compensation involved fibers of all

ISSN:0148-639X    

DOI:10.1002/mus.880130708

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

年代:1990

数据来源: WILEY

摘要:

AbstractLocal cooling of the muscle resulted in significant increases in M wave surface areas in patients with ALS, myasthenia gravis, the Lambert‐Eaton myasthenic syndrome, and also in controls. The most striking increases were seen in patients with early ALS who had minimal lower motor neuron involvement and/or little defect on neuromuscular transmission and patients with the myasthenic syndrome. Patients with myasthenia gravis had intermediate increases between these groups and the controls; there was a large increases in M wave surface area in myasthenia gravis compared with controls but this could be accounted for by improvement in neuromuscular transmission. The large increase in M wave surface area in early ALS could be the result of temporal summation of individual muscle fibers in motor units with increased fiber densities. The increase in both ALS and the myasthenic syncrome could result also from the loss of a trophic factor causing changes at the muscle membran

ISSN:0148-639X    

DOI:10.1002/mus.880130709

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

年代:1990

数据来源: WILEY

摘要:

AbstractA 23‐year‐old woman with McArdle' disease performed mild leg exercise on a bicycle ergometer. Saline or 10% glucose solution was infused throughout exercise. After exercise with saline infusion, her plasma concentration of ammonia, hypoxathine and creatine kinase increased greatly. Conversely, after exercise with glucose infusion, there were no appreciable changes in these plasma substances. In addition, she noticed that glucose infusion relieved her from muscle symptoms during exercise. These findings seggest that glucose infusion to patiets with McArdle' desease ameliorates excessive ATP degradation in exercising musc

ISSN:0148-639X    

DOI:10.1002/mus.880130710

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

年代:1990

数据来源: WILEY

摘要:

AbstractWe have measured the firing rate and amplitude of 4551 motor unit action potentials (MUAPs) recorded with concentric needle electrodes from the brachial biceps muscles of 10 healthy young adults before, during, and after 45 minutes of intermittent isometric exercise at 20% of maximum voluntary contraction (MVC), using an automatic method for decomposition of electromyographic activity (ADEMG). During and after exercise, MUAPs derived from contractions of 30% MVC showed progressive increase in mean firing rate (P ⩽ .01) and amplitude (P ⩽ .05). The firing rate increase preceded the rise in mean amplitude, and was evident prior to the development of fatigue, defined as reduction of MVC. Analysis of individual potentials revealed that the increase in firing rate and in amplitude reflected different MUAP subpopulations. A short‐term (<1 minute) reduction in MUAP firing rates (P ⩽ .05) was also observed at the onset of each test contraction. These findings suggest that motor units exhibit a triphasic behavioral response to prolonged submaximal exercise: (1) short‐term decline and stabilization of onset firing rates, followed by (2) gradual and progressive increase in firing rates and firing variability, and then by (3) recruitment of additional (larger) motor units. The (2) and (3) components presumably compensate for loss of force‐generating capacity in the exercising muscle, and give rise jointly to the well‐known increase in total surface EMG which accompanies m

ISSN:0148-639X    

DOI:10.1002/mus.880130711

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

年代:1990

数据来源: WILEY