摘要:

AbstractMotoneurons can be activated both reflexly and antidromically following electrical stimulation of peripheral nerves. These H reflexes and F waves are clinically useful responses which interface at the level of the peripheral nerves and the spinal cord. Because these responses are commonly employed in the electrodiagnostic evaluation of patients, an understanding of their physiology and clinical applications is important. These are reviewed. Reasoning from the physiology, both the value and limitations of H‐reflex and F‐wave studies are considered for disorders of peripheral nerves, roots, and the central nervous system. Theoretical concepts about the physiology and pathophysiology of the nervous system based on H‐reflex and F‐wave data are also discussed. © 1992 John Wiley&S

ISSN:0148-639X    

DOI:10.1002/mus.880151102

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

年代:1992

数据来源: WILEY

摘要:

AbstractWe desribe 2 patients of Jewish Libyan descent, who presented with a clinical syndrome compatible with Creutzfeldt–Jakob disease and who were found to have a mutation of codon 200 in the prion protein. The patients developed symptoms and signs of peripheral nerve involvement diagnosed by electrodiagnostic and histopathological studies as demyelinating neuropathy. This may be a rare manifestation of Creutzfeldt–Jakob disease. © 1992 John Wiley&Sons,

ISSN:0148-639X    

DOI:10.1002/mus.880151103

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

年代:1992

数据来源: WILEY

摘要:

AbstractThe usefulness of multichannel surface recording of fasciculations was evaluated by a retrospective study of 116 patients with various neurological disorders. Eight channels of a conventional electroencephalograph were used with plate electrode recordings from the upper arms and legs. Widespread fasciculations (defined as five or more of the eight muscle groups) were recorded in 48 of 54 patients with motor neuron disease, spinal muscular atrophy or postpolio syndrome, but noted on routine clinical examination at presentation in only 6. Eleven of 23 patients with peripheral neuropathy or myelopathy had fasciculations in five or more leads compared to one clinically, and 3 of 39 with other neurological diseases had fasciculations electrically but in only one were they clincally observed. The method is a noninvasive and sensitive adjunct to clinical examination for detecting fasciculations. Its diagnostic value is limited by the relatively high incidence of fasciculations in neuropathies and myelopathies. However, this study suggests that “false negatives” are rare and that the diagnosis of motor neuron disease should be reconsidered when less than five leads shows fasciculations. © 1992 John Wiley&Sons,

ISSN:0148-639X    

DOI:10.1002/mus.880151104

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

年代:1992

数据来源: WILEY

摘要:

AbstractWe report, for the first time, muscle immunocytochemical studies in sporadic, adult onset myotubular myopathy (SAOMM), which show intramyofibrillar central, perinuclear desmin and vimentin. This pattern was absent in a normal control and in myofibers with increased internal nuclei associated with denervation and myotonic muscular dystrophy (MyD). These findings resemble those reported in 8‐ to 15‐week‐old human fetal myotubes and myofibers of infantile MM, implying a possible regression of intermediate filaments of adult myofibers to an early developmental phase in SAOMM. © 1992 John Wiley&Son

ISSN:0148-639X    

DOI:10.1002/mus.880151105

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

年代:1992

数据来源: WILEY

摘要:

AbstractMedian motor studies are commonly “normal” in mild carpal tunnel syndrome (CTS). This reflects either the sparing of motor compared to sensory fibers, or the inability of conventional studies to detect an abnormality. A novel approach to demonstrate early motor fiber involvement in CTS is the placement of the same active electrode lateral to the third metacarpal, allowing recording from the second lumbrical or the deeper interossei, when stimulating the median or ulnar nerves at the wrist, respectively. We compared the difference between these latencies in 51 normal control hands to 107 consecutive patient hands referred with symptoms and signs suggestive of CTS, who were subsequently proven to have electrophysiologic CTS by standard nerve conduction criteria. A prolonged lumbrical—interossei latency difference (>0.4 ms) was found to be a sensitive indicator of CTS in all patient groups. It was also helpful in patients with coexistent polyneuropathy, where localization at the wrist was otherwise difficult. © 1992 John Wiley&Son

ISSN:0148-639X    

DOI:10.1002/mus.880151106

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

年代:1992

数据来源: WILEY

摘要:

AbstractIn skeletal muscles from rats treated with germanium for 23 weeks, there were numerous ragged‐red fibers and cytochrome‐coxidase (COX)‐deficient fibers. Biochemically, germanium reduced the enzyme activities in the mitochondrial respiratory chain. Rotenone‐sensitive NADH–cytochrome‐creductase as well as COX activities were markedly reduced, while succinate–cytochrome‐creductase was less severely, but significantly, affected. The histopathological findings in these muslces were similar to those seen in patients with mitochondrial encephalomyopathy, suggesting that germanium‐induced myopathy may be a useful experimental model. Coenzyme Q10administration appeared to be ineffective in preventing this experimental myopathy. © 1992 Jo

ISSN:0148-639X    

DOI:10.1002/mus.880151107

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

年代:1992

数据来源: WILEY

摘要:

AbstractA patient in whom multiple sclerosis (MS) was ultimately diagnosed presented with a lower motor neuron syndrome involving 1 hand, with EMG evidence of denervation. Twelve other patients were subsequently identified with definite MS and asymmetric hand atrophy. These patients were studied clinically and electrophysiologically. Evidence of chronic and ongoing denervation was noted in the hands of 12 of the 13 patients; in only 3 patients could the EMG abnormalities be accounted for by peripheral nerve lesions. Thus, lesions resulting in lower motor neuron damage may occur in the central nervous system in MS patients. We suggest that demyelination in the region of the ventral root exit zone may account for these findings. © 1992 John Wiley&Sons, Inc

ISSN:0148-639X    

DOI:10.1002/mus.880151108

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

年代:1992

数据来源: WILEY

摘要:

AbstractInfection of human embryonic myoblasts by West Nile virus (WNV), a flavivirus, caused significant upregulation of class I and II MHC expression as determined by flow cytometry. After 48 hours at a multiplicity of infection of 5 pfu/cell, a sixfold increase in MHC class I expression was induced from initially low levels of expression. In contrast, MHC class II was induced de novo to five times the control fluorescence level. At least 70% of the cells were infected as determined using fluorescence microscopy and anti‐WNV antibody labeling. Myoblasts were>90% pure as shown by anti–Leu‐19 labeling. MHC class I (but not class II) was increased threefold after exposure to virus‐inactivated supernatant from 48‐hour–infected cells, indicating the presence of factor(s) contributing to the MHC class I increase. These findings may be important in establishing a link between viral infection of human cells and induction of inflammatory autoimmune disease. We discuss the possibility of using WNV as an in vivo model. © 1992 John Wil

ISSN:0148-639X    

DOI:10.1002/mus.880151109

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

年代:1992

数据来源: WILEY

摘要:

AbstractA technique for eliciting and recording the stretch reflex (R) of the medial pterygoid muscle (Pter) is described. The latency was 6.9 ± 0.43 ms in 23 healthy volunteers (mean age 23.7 years) showing a side‐to‐side difference of 0.29 ± 0.21 ms. The PterR latencies were little shorter and side‐to‐side difference little greater than of the masseter reflex. Observations in 5 selected patients with small brainstem lesions suggest that the neurons of the PterR afferents form a cluster within the caudal portion of the trigeminal mesencephalic nucleus. Testing the masseter and pterygoid reflexes provides a more precise localization of small ponto‐mesencephalic lesions. © 1992 John Wil

ISSN:0148-639X    

DOI:10.1002/mus.880151110

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

年代:1992

数据来源: WILEY

摘要:

AbstractThe presence, morphology, distribution, and abundance of axonal swellings in intramuscular nerves were evaluated. Axonal swellings were present in intramuscular nerves in 42% of 127 muscle biopsies from patients with a variety of conditions. The incidence was highest in muscle from patients with peripheral neuropathy, but swellings were present in muscle from patients with motor neuron disease, primary muscle diseases, and some individuals without clinical or histological evidence of neuromuscular disease. The greatest number of swellings in intramuscular nerves was in muscle from patients with chronic inflammatory demyelinating neuropathy. Swellings were spherical or elliptical, 4–20 μm in diameter, 5–30 μm in length, and composed of neurofilaments. Swellings were present only in myelinated axons of intramuscular nerves, proximal to nodes of Ranvier or in internodal regions. Swellings were not associated with axonal degeneration. They were probably not transported. The formation or accumulation of swellings may reflect altered axonal dynamics common to a number of disease processes. © 1992 John Wiley&Son

ISSN:0148-639X    

DOI:10.1002/mus.880151111

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

年代:1992

数据来源: WILEY