bluuebunny/crossref_metadata_2025 huggingface dataset:
Severe acute axonal form of Guillain–Barré syndrome associated with IgG anti‐GD1a antibodies
Authors: Yuki Nobuhiro , Yoshino Hiide , Sato Shuzo , Shinozawa Kazuki , Miyatake Tadashi
Published: January 2005

We report cases of 2 patients with pure motor Guillain‐‐Barré syndrome of explosive onset who required mechanical ventilation for more than 2 months. Their electrophysiologic findings and poor clinical recoveries suggested severe axonal degeneration involving the motor nerves. Enzymelinked immunosorbent assay and thin‐layer chromatogram‐immunostaining showed the sera of both patients had high IgG antibody titer against GD1a ganglioside. Their titers decreased with the clinical course of the illness. GD1a as well as GM1, appears to be the target pathogenic antigen in motor axon disorders. Elevated IgG anti‐GD1a antibody titer may prove useful for predicting severe GBS. © 1992 John Wiley & Sons, Inc.
Obstetrical lumbosacral plexus injury
Authors: Feasby T. E. , Burton S. R. , Hahn A. F.
Published: January 2005

Injuries to the lumbosacral plexus during labor and delivery have been reported in the literature for years, but have lacked electrophysiologic testing to substantiate the location of the nerve injury. We report 2 cases with comprehensive electrophysiologic testing which localizes the site of this obstetrical paralysis to the lumbosacral trunk (L4‐5) and S‐1 root where they join and pass over the pelvic rim. The paralysis may be mild or severe. Small maternal size, a large fetus, midforceps rotation, and fetal malposition may place the mother at risk for this nerve injury. © 1992 John Wiley & Sons, Inc.
AAEM case report #25: Anterior interosseous nerve syndrome
Authors: Wertsch Jacqueline J.
Published: January 2005

A case study is reported regarding a 57‐year‐old woman, chose chief complaint was weakness in her thumb that she had noted while gardening. The patient described difficulty pulling weeks out because of an inability to get a firm grip when using the thumb. Physical examination showed weakness of the flexor pollicis longus and flexor digitorum profundus to the index finger. There was no other weakness and no clinical sensory deficit. Electrodiagnostic studies revealed normal median motor and sensory nerve conduction studies with needle examination abnormalities noted only in the flexor pollicis longus, flexor digitorum profundus, and pronator quadratus. The literature on anterior interosseous nerve syndrome (AINS) is reviewed. It is important to differentiate those with idiopathic AINS as part of a neuralgic amyotrophy picture from those with an anatomic cause such as a fibrous band or anomalous muscle. Electrodiagnostic examination can be useful to help make this distinction. © 1992 John Wiley & Sons, Inc.
Immunocytochemical localization of the multicatalytic proteinase (Proteasome) in crustacean striated muscles
Authors: Beyette Jill R. , Mykles Donald L.
Published: January 2005

Multicatalytic proteinase (MCP) is thought to play a central role in the processing and turnover of intracellular proteins in eukaryotic cells. Immunocytochemistry was used to determine the intracellular distribution of the MCP in the claw muscles of the land crab, Gecarcinus lateralis, and the claw and abdominal muscles of the American lobster, Homarus americanus. Cryosections were stained with an affinity‐purified polyclonal antibody to lobster MCP that cross‐reacted with the land crab enzyme. Two types of staining were observed: a diffuse cytoplasmic staining, and a dense aggregate staining primarily associated with invaginations of the cell membrane. The cytoplasmic staining appeared reticulated in favorable transverse sections due to a preferential localization of MCP to the intermyofibrillar space. The aggregate staining was associated with neither nuclei nor mitochondria, since stains specific for these organelles (Hoechst stain and nicotinamide adenine dinucleotide diaphorase histochemistry, respectively) did not colocalize with the aggregates. Trypsinlike peptidase activities of isolated microsomal and postmicrosomal fractions indicated that less than 1% of the total MCP was associated with the microsomal fraction. Immunoprecipitaion of the same fractions confirmed the presence of MCP in the microsomes as well as in the cytosol. These results suggest that the MCP is primarily associated with cytoplasmic components; the aggregate staining may result from the association of the MCP with cellular membrane systems. © 1992 John Wiley & Sons, Inc.
Demyelinating peripheral neuropathy in Creutzfeldt–Jakob disease
Authors: Neufeld Miriam Y. , Josiphov Joseph , Korczyn Amos D.
Published: January 2005

We 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, Inc.
Axonal swellings in human intramuscular nerves
Authors: Alderson Kathy
Published: January 2005

The 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 & Sons, Inc.
Perineurial cell hypertrophic mononeuropathy manifesting as carpal tunnel syndrome
Authors: Mitsumoto Hiroshi , Estes Melinda L. , Wilbourn Asa J. , Culver James E.
Published: January 2005

A 42‐year‐old man showed signs and symptoms suggestive of carpal‐tunnel syndrome, but EMG showed an isolated motor axon‐loss lesion affecting the right median nerve distally. After the MRI revealed a mass in the median nerve, surgical exploration showed a diffusely swollen median motor branch. Biopsy showed a lesion with marked onion‐bulb formation composed of perineurial cells as identified by immunohistochemical analyses and electron microscopic examination. Although we previously coined the term “perineurioma” for this condition, re‐reviews of our cases do not support the idea that the onion‐bulb lesion is a benign tumor; instead, it appears to be reactive hyperplasia. Although rare, electromyographers and neurologists need to be aware of this problem because it is selflimited and does not require surgical resection. © 1992 John Wiley & Sons, Inc.
Duration of amyotrophic lateral sclerosis is age dependent
Authors: Eisen Andrew , Schulzer Michael , MacNeil Maureen , Pant Bhanu , Mak Edwin
Published: January 2005

Since 1985, we prospectively followed 246 patients with ALS. The relation ship between the age of developing neurological impairment and disease duration was analyzed in 138 patients (86 men and 52 women) who died. Mean disease duration was 4.0 ± 3.8 years for men and 3.2 ± 2.5 years for women. There was an inverse, exponential, relationship between onset age and duration (goodness‐of‐fitP> 0.05). Mean duration at onset age 40 years was 8.2 ± 5.0 years compared with 2.6 ± 1.4 years for patients aged 61 to 70 years (P> 0.001). The ratio of young (40 years) men to women was 3.6:1. When matched for age, disease duration was the same for patients with bulbar and nonbulbar onsets. We conclude that onset age, but no sex, is the most significant predictor determining disesae duration in ALS. Longer survival in younger patients probably reflects their greater neuronal reserve. © 1993 John Wiley & Sons, Inc.
Polyneuropathy associated with IgA monoclonal gammopathy of undetermined significance
Authors: Simmons Zachary , Bromberg Mark B. , Feldman Eva L. , Blaivas Mila
Published: January 2005

Although polyneuropathies associated with IgM and IgG monoclonal gammopathies have been well described, polyneuropathy with IgA monoclonal gammopathy of undetermined significance (MGUS) is less commonly seen and has not been well studies. We reviewed the clinical and electrodiagnostic features of 5 such patients, and the sural nerve biopsy findings in 4 of them. One patient was diabetic, while 4 were free of other diagnoses commonly associated with neuropathy. Clinical presentations were varied. Electrodiagnostic and histological studies ranged from primary demyelination to primary axon loss to a mixed axonal/demyelinating picture. Three patients who were treated appeared to respond to prednisone or intravenous gamma globulin, despite clear clinical, electrodiagnostic, and histological differences. We conclude that the polyneuropathy associated with IgA MGUS is heterogeneous, similar to that in IgM and IgG MGUS. A trial of immunomodulating therapy appears to be warranted in such patients if the neuropathy is sufficiently servere. © 1993 John Wiley & Sons, Inc.
Comparative effects of ischemia and acute hypoxemia on muscle afferents from tibialis anterior in cats
Authors: Lagier‐Tessonnier Francoise , Balzamo Emmanuel , Jammes Yves
Published: January 2005

Comparative effects of ischemia and acute hypoxemia (PaO2 = 24 mm Hg) were studied in anesthetized cats on afferents from the tibialis anterior limb muscle. Metaboreceptors (groups III and IV fibers) and mechanoreceptors were identified by their activation by an intraarterial injection of lactic acid (LA) or high‐frequency vibrations (HFV) applied to the extremity of the muscle tendon, respectively. Ischemia and hypoxemia exerted opposite influences on the two categories of muscle afferents: they depressed the response of mechanoreceptors to HFV, but markedly enhanced the spontaneous tonic activity of metaboreceptors. The effects of hypoxamia were delayed but slightly greater and lasted longer during the recovery period than those exerted by ischemia. The inhibitory action on mechanoreceptors exerted by a reduced oxyden supply to muscle is interpreted as a result from local acidosis. Indeed, under normoxic conditions, a LA bolus injection during the HFV test also reduced the firing rate of these receptors. © 1993 John Wiley & Sons, Inc.
Plasma carnitine insufficiency and effectiveness of L‐carnitine therapy in patients with mitochondril myopathy
Authors: Campos, Yolanda , Huertas Rosa , Lorenzo Gustavo , Bautista Juan , Gutierrez Eduardo , Aparicio Manuel , Alesso Luis , Arenas Joaquin
Published: January 2005

Plasma carnitine “insufficiency,” (plasma esterified carnitine to free carnitine ratio above 0.25) was found in 21 48 (43.8%) patients with mitochondrial myopathy, of whom 4 also showed both total and free carnitine deficiencies in plasma. In addition, plasma levels of SCAC and LCAC were higher in patients with mitochondrial myopathy than in controls (P < 0.001 and P <0.01, respectively). Patients diagnosed as having plasma carnitine insufficiency or deficiency were treated with L‐carnitine (50–200 mg/kg per day in four daily doses). Muscle weakness improved in 19 of 20 patients, failure to thrive in 4 of 8, encephalopathy in 1 of 9, and cardiomyopathy in 8 of 8 patients. Plasma carnitine “insufficiency” provides an additional clue to the diagnosis of mitochondrial myopathy and an indication for L‐carnitine therapy. © 1993 John Wiley & Sons, Inc.
Use of the surface EMG signal for performance evaluation of back muscles
Authors: De Luca Carlo J.
Published: January 2005

For well over a decade my associates and I have been developing an objective, noninvasive technique to evaluate the performance of low‐back muscles, with emphasis on being able to distinguish between healthy and dysfunctioned backs. Our approach is based on the well‐known fact that the EMG signal undergoes a compression in the frequency domain during a sustained muscle contraction. In particular we track the median frequency of EMG signals detected from six muscles in the lower back during an isometric extension of the trunk. The measurements are taken with the Back Analysis System which consists of a postural restraining device, special electrodes for detecting the EMG signals, a muscle fatigue monitor which calculates the median frequencies, and the appropriate software. We have found that the pattern of fatigue exhibited by the six median frequency curves can be used to distinguish individuals who have low‐back pain from those who do not with an accuracy of at least 84%. An even more relevant and timely application of our technique is for quantifying the progression of the performance of low‐back muscles during a rehabilitation program. Although more work is required to explore the intricacies of the technique, present results provide a convincing indication that it is reliable and that it is ready to be placed into practice. © 1993 John Wiley & Sons, Inc.
Determining heart‐rate variability: Comparing methodologies using computer simulations
Authors: Harry Jason D. , Freeman Roy
Published: January 2005

Heart rate variation due to respiration is a window onto autonomic nervous system function and many measures exist that quantify this variability. Computer‐based simulations of 1‐minute deep‐breathing tests, along with common artifacts, were used to compare the most frequently used measures. We found distinct differences in the performance of the measures. Some measures (e.g., SDRR and MSSD) are strongly influenced by the underlying mean heart rate while others (e.g., Max–Min and SDHR) are not. All of the measures tested, except R, were influenced by both shifting mean heart rate and single‐beat anomalies. R, on the other hand, is strongly influenced by test duration and breathing asynchronies. Sensitivity to phenomena unrelated to ANS function can reduce the diagnostic discrimination of these measures. We suggest simple improvements to the measures and discuss how some measures may be theoretically superior to others. © 1993 John Wiley & Sons, Inc.
Burn injury—induced nicotinic acetylcholine receptor changes on muscle membrane
Authors: Ward Joanna M. , Martyn J. A. Jeevendra
Published: January 2005

Patients with thermal injury show pharmacological responses akin to those seen following denervation of motor nerve where there is an increase in the number of muscle‐type acetylcholine receptors (AChR). This study in the rat, examined the effect of 20%, 30%, and 50% body surface area burn injury on gastrocnemius and diaphragm AChR number, quantitated by [125I]α‐bungarotoxin (α‐BGT). Pharmacodynamic responses to D‐tubocurarine were evaluated in the gastrocnemius muscle. AChR from gastrocnemius muscle were significantly increased in all burn groups at 14 days after burn. After 28 days, the AChR had returned to control in the 20% and 30% burn groups, but persisted in the 50% burn group. AChR from diaphragm did not show significant changes between groups. Resistance to D‐tubocurarine was not seen in burn groups compared with controls. Burn trauma causes increases of AChR at sites distant from the area of injury. Diaphragm muscle may be less sensitive than gastrocnemius to mediators which upregulate AChR. © 1993 John Wiley & Sons, Inc.
The estimated numbers and relative sizes of thenar motor units as selected by multiple point stimulation in young and older adults
Authors: Doherty Timothy J. , Brown William F.
Published: January 2005

Multiple point stimulation (MPS) is described as a method of estimating the numbers of motor units in the median innervated thenar muscles of young and older control subjects. Stimulation at multiple sites along the course of the median nerve was employed to collect a sample of the lowest threshold, all‐or‐nothing surface‐recorded motor unit action potentials (S‐MUAPs). The average, negative peak area, and peak‐to‐peak amplitude of the sample of S‐MUAPs was determined and divided into the corresponding value for the maximal compound muscle action potential to derive the motor unit estimate (MUE). In 37 trials from 17 younger subjects (20—40 years), the mean MUE was 288 ± 95 SD based on negative peak area and, in 33 trials from 20 older subjects, mean values were 139 ± 68. In 23 young and older subjects, MPS was performed on at least two occasions and the MUEs were found to be highly correlated (r = 0.88). © 1993 John Wiley & Sons, Inc.
The clinical significance of type 1 fiber predominance
Authors: Kyriakides Theodore , Silberstein Jonathon M. , Jongpiputvanich Sungkom , Silberstein E. Peter J. , Walsh Peter J. , Gubbay Sonny S. , Kakulas Byron A.
Published: January 2005

In the course of investigating children with hypotonia, muscle biopsy of the vastus lateralis frequently demonstrates greater than 55% predominance of the aerobic type 1 fibers of “type 1 fiber predominance” (T1FP). The clinical significance or T1FP is not well known. T1FP can be associated with a variety of neurological disorders but a significant proportion has no apparent cause. We followed up 23 children with T1FP to establish whether a neurological disorder subsequently became apparent or whether a distinct clinical entity of T1FP could be identified. Sixty percent of the children were found to have a specific neurological disorder, while 40% did not and may represent a distinct clinical entity. The majority of children with the clinical entity of T1FP improved although some were left with mild motor disability. Such information is important for counseling when patients with T1FP are first assessed. © 1993 John Wiley & Sons, Inc.
Case of the month. Latex hypersensitivity following exposure to gloves during electromyography
Authors: Massagli Teresa L. , Cox Rodde D. , Griggs Robert C. , Mendell Jerry R. , Miller Robert G.
Published: January 2005

A case of a 7‐year‐old boy with myelodysplasia who developed a local acute hypersensitivity reaction after exposure to latex gloves during electromyography is presented. Anaphylaxis from latex gloves has been recently reported, especially in patients with myelodysplasia. Allergens from rubber gloves can be introduced under the skin during EMG and could cause local or systemic acute hypersensitivity reactions. Electromyographers should elicit a history to rule out rubber allergy and use vinyl gloves if suspicion of allergy exists. © 1993 John Wiley & Soncs, Inc.
Discharge properties of single motor units in patients with spinal cord injuries
Authors: Wiegner Allen W. , Wierzbicka M. Margaret , Davies Llewelyn , Young Robert R.
Published: January 2005

To study neurophysiological correlates of spastic paresis, we analyzed the discharge pattern of single motor units (SMUs) during sustained voluntary contraction from muscles weakened by spinal cord injury (SCI) and from muscle of near normal strength just at or above the level of injury., The average firing rate of SMUs was reduced in patients' biceps brachii and tibialis anterior muscles compared with controls, but not in the triceps brachii. Floating serial correlation coefficients obtained form successive interdischarge intervals were significantly more positive in patients than in controls in all three muscles. One statistical measure of regularity of discharge, akin to a coefficient of variation, was best able to differentiate patient and control SMUs. Increased discharge variability in muscle just above the level of injury suggested that subtle effects of traumatic SCIs were more extended than was clinically apparent. Although consistent statistical differences could be measured, these changes were not specific to SCI, nor were all SMUs equally affected. © 1993 John Wiley & Sons, Inc.
Localization of GM1 and GD1b antigens in the human peripheral nervous system
Authors: Kusunoki Susumu , Chiba Atsuro , Tai Tadashi , Tai Tadashi , Kanazawa Ichiro
Published: January 2005

Serum antibodies against ganglioside GM1 and/or GD1b are frequently detected in autoimmune neuropathies such as multifocal motor neuropathy, IgM paraproteinemic neuropathy and Guillain–Barré syndrome. Some of them bind to GM1 or GD1b monospecifically but others cross‐react with both of the antigens. In order to investigate the respective localizations of GM1 and GD1b antigens in the human peripheral nervous system, an immunohistochemical study was performed using two mouse monoclonal antibodies, each monospecific to GM1 and GD1b. GGR12, monospecific to GD1b, bound to neurons in dorsal root ganglia and sympathetic ganglia, and some parts of the peripheral myelin, mainly the paranodal areas. However GMB16, monospecific to GM1, did not bind to either neurons or myelin. GD1b antigen present on neurons and paranodal myelin in the peripheral nervous system can be a target antigen of serum antibodies in autoimmune neuropathies. Further effort should be made to reveal the localization of GM1 antigen in the human peripheral nervous system.
Recovery of muscle after different periods of denervation and treatments
Authors: Finkelstein David I. , Dooley Philip C. , Luff Anthony R.
Published: January 2005

Three aspects of reinnervation and recovery of skeletal muscle following various periods of denervation were investigated: (1) the effect of duration of denervation; (2) the effect of hyperthyroidism on recovery; and (3) whether the muscle or the nerve limits recovery. The rat medial gastrocnemius (MG) nerve was cut and then resutured after 0, 3, 7, 21, or 56 days. In a second group of animals, the MG muscle was denervated and, in addition, the animal received triiodothyronine (T3) supplementation during reinnervation. The third group of animals had the denervated MG muscle reinnervated by a larger number of newly transected foreign axons. The force produced by the reinnervated muscle depends on the period that the muscle was denervated. Recovery was impaired when the period of denervation exceeded 7 days. T3 treatment did not benefit the return of force production, nor did providing the muscle with a larger number of newly transected axons.
Electrophysiological mapping of the segmental innervation of the saphenous and sural nerves
Authors: Phillips Lawrence H. , Park T. S.
Published: January 2005

Delineation of an area of sensory loss is often helpful in localizing a lesion at the spinal or root level. We have studied the segmental innervation of two cutaneous nerves, the saphenous and the sural, during selective posterior rhizotomy. Each nerve was stimulated electrically, and recordings were made from dorsal roots L‐3 to S‐2 in 30 patients. We found that both nerves received innervation through at least three spinal levels. The level of maximum innervation was approximately equally divided between L‐3 and L‐4 for the saphenous nerve. The sural nerve received maximum innervation through S‐1 in 80% of the cases, but the remainder came through L‐5 or S‐2. These findings provide electrophysiologic evidence that these cutaneous nerves have multiple segmental supply, and the sensory area they supply does not lie solely within a single dermatome.© 1993 John Wiley & Sons, Inc.
Sarcoid myopathy presenting with diaphragm weakness
Authors: Dewberry Robert G. , Phillips Lawrence H. , Schneider Bernard F. , Cale William F.
Published: January 2005

Sarcoidosis involving muscle occurs frequently, but it is infrequently symptomatic. The clinical, electromyographic, and histologic features of sarcoidosis involving muscle in a 63‐year‐old woman presenting with diaphragm weakness are described. An electromyogram revealed widespread myotonia and an inflammatory myopathic process, suggestive of adult‐onset acid maltase deficiency disease. Muscle biopsy showed noncaseating granulomas consistent with sarcoidosis. Clinical improvement followed the initiation of oral prednisone therapy. This case illustrates that muscular sarcoidosis may mimic adult‐onset acid maltase deficiency in both its clinical and electromyographic features. © 1993 John Wiley & Sons, Inc.
Colchicine alters apamin receptors, electrical activity, and skeletal muscle relaxation
Authors: Vergara Cecilia , Ramirez Beatriz , Behrens María Isabel
Published: January 2005

A low conductance calcium‐activated K+ channel is thought to regulate the rate of firing of several excitable cells. In skeletal muscle the expression of this channel is under nerve control. Previously, we reported that axonal flow blockade of rat nerves, induced by colchicine, caused atransient increase in muscle apamin receptors, determined by 125I‐apamin binding to membrane fractions. The increase in apamin receptors was correlated with repetitive discharges resembling myotonic potentials in the electromyogram, that were blockable by apamin. Here we show that the increase in muscle apamin receptors and the alteration of the electromyogram are followed closely by a slowing of the twitch relaxation, that in turn, is decreased by apamin. Furthermore, the presence of myotonic‐like alterations in the electromyogram and a slowing of muscle relaxation when muscle apaminreceptors are increased suggests that these channels may participate, amongother factors, in the generation of some kinds of myotonia. © 1993 John Wiley & Sons, Inc.
Use and misuse of conventional electrodiagnosis, quantitative sensory testing, thermography, and nerve blocks in the evaluation of painful neuropathic syndromes
Authors: Verdugo Renato J. , Ochoa José L.
Published: January 2005

A number of laboratory tests are critically important in the quest to diagnose presence or absence of organic neuropathic dysfunction and to establish the relevance of such to the subjective pain complaints. However, none of these tests has absolute diagnostic value and their results must be interpreted in the light of the clinical picture. Conventional electrophysiology evaluates function of large caliber afferent and motor fibers leaving the function of small caliber afferent fibers unexplored, and cannot explore the basis for positive sensory phenomena. The quantitative somatosensory thermotest is the best test available to explore function of small caliber afferents. It allows documentation of positive sensory phenomena in the form of thermal hyperalgesia. Because it is a psychophysical test, it lacks localizing value. Thermography sensitively detects and precisely delineates areas of cutaneous thermal change of neural origin. Three types of diagnostic neurologic blocks are used in the clinic: compression‐ischemia, local anesthetic and sympathetic blocks. Although they may provide important information about the pathophysiology of pain and hyperalgesias, adequate placebo control is of the essence because chronic neuropathic pain patients may express a high incidence of placebo response. © 1993 John Wiley & Sons, Inc.
Human microneurography and intraneural microstimulation in the study of neuropathic pain
Authors: Torebjörk Erik
Published: January 2005

Psychophysical experiments in combination with microneurography and intraneural microstimulation in awake human subjects have yielded some useful information on somatosensory functions under normal and pathologic conditions. Normally, pain is signaled by nociceptive afferents, and tactile sensations are evoked from activation of low‐threshold mechanoreceptors. Following tissue injury, nociceptors are sensitized, and their enhanced responsiveness correlates with hyperalgesia to heat and in some cases to mechanical stimuli. In addition, ongoing activity in sensitized nociceptive afferents may lead to central sensitization in such a way that normally nonpainful gentle stroking the skin evokes pain from activation of low‐threshold mechanoreceptors. This particular change in signal processing in the central nervous system is restored when the ongoing nociceptive input is interrupted, whereas other forms of central sensitization can outlast the duration of the nociceptive input. © 1993 John Wiley & Sons, Inc.
Development and reversal of fatigue in human tibialis anterior
Authors: Reid Michael B. , Grubwieser Gert J. , Stokic Dobrivoje S. , Koch Stephen M. , Leis A. Arturo
Published: January 2005

The lack of easily measurable, objective physiologic indices of muscle fatigue in humans has hampered the evaluation of interventions that putatively inhibit muscle fatigue. In 6 healthy subjects, isometric fatigue of right and left tibialis anterior (TA) was produced using 180 s of intermittent electrical stimulation to the motor point (40 Hz, 650‐ms or 250‐ms trains, 1 train/s). The time course, magnitude, and reproducibility of fatigue and recovery from fatigue was established, and the effect of duty cycle measured. During fatigue, force fell rapidly in all subjects over the first 70 s, then fell more slowly. Recovery was also biphasic—force increased rapidly over the initial 30 s then slowly—and was incomplete at 300 s. Comparing duty cycles of 0.65 versus 0.25, the longer duty cycle caused a greater fall in force (–65% versus –29%; P < 0.001) and lower recovery (P < 0.02). In all subjects, left leg muscles fatigued more than right. We conclude that this noninvasive fatigue and recovery protocol is highly reproducible and that it may prove useful for evaluating the effects of pharmacologic or restorative interventions on human muscle fatigue. © 1993 John Wiley & Sons, Inc.
Sensitivity of three median‐to‐ulnar comparative tests in diagnosis of mild carpal tunnel syndrome
Authors: Uncini Antonino , Dimuzio A. , Awad J. , Manente G. , Tafuro M. , Gambi D.
Published: January 2005

We studied 193 hands of 113 patients referred for typical carpal tunnel syndrome (CTS). Ninety‐five (49%) hands had normal median distal motor latency (≤4.2 ms) and normal or borderline sensory conduction velocity from digit 2 stimulation (≥45 m/s). In these cases we performed three median to ulnar comparative tests: (1) difference between median and ulnar distal motor latencies recorded from the second lumbrical and interossei muscles (2L‐INT); (2) difference between median and ulnar sensory latencies from digit 4 stimulation (D4M‐D4U); and (3) difference between median and ulnar mixed nerve latencies from palmar stimulation (PM‐PU). The 2L‐INT difference was ≥0.6 ms in 10% of hands. PM‐PU and D4M‐D4U were ≥0.5 ms in 56% and 77% of hands, respectively. The greater sensitivity of D4M‐D4U might be explained by the funicular topography and consequent greater susceptibility to compression of the cutaneous fibers from the third interspace which, at the distal carpal tunnel, are clumped superficially in the anteroulnar portion of the median nerve just beneath the transverse ligament. © 1993 John Wiley & Sons, Inc.
Focal myositis of the temporal muscle
Authors: Naumann Markus , Toyka Laus Viktor , Goebel Hans H. , Hofmann Erich , Reichmann Heinz
Published: January 2005

Focal myositis is a rare inflammatory disease of the skeletal muscle that may involve any part of the body. We present a 19‐year‐old man with a short history of a painful pseudotumor in the right temporal region. MRI pictures showed a swollen right temporal muscle and muscle biopsy revealed the characteristic histological and immunocytochemical findings of polymyositis. © 1993 John Wiley & Sons, Inc.
Issues & Opinions: Practice parameter for electrodiagnostic studies in carpal tunnel syndrome: Summary statemem: American association of electrodiagnostic medicine, american academy of neurology, american academy of physical medicine and rehabilitation
Authors: Jablecki Charles K.
Published: January 2005

Carpal tunnel syndrome (CTS) is the most common peripheral mononeuropathy and often requires one or more therapies including surgery. The results of electrodiagnostic (EDX) studies have been found to be highly sensitive and specific for the diagnosis of CTS. This document defines the standards, guidelines, and options for EDX studies of CTS based on a critical review of the literature.
Immunohistochemical characterization of human masseter muscle spindles
Authors: Eriksson Per‐Olof , Butler‐Browne Gill S. , Thornell Lars‐Eric
Published: January 2005

An enzyme‐ and immunohistochemical study has been performed on human masseter muscle spindles. Antibodies selective for different myosin heavy chain (MHC) isoforms and M‐band proteins (M‐protein, myomesin, and MM‐CK) were used. The expression of these proteins was determined in the different intrafusal fiber types. Nuclear bag1 and nuclear bag2 fibers expressed predominantly slow‐twitch and slow‐tonic MHCs. The bag2 fibers in addition contained fetal MHC. Nuclear chain fibers coexpressed embryonic, fetal, and fast‐twitch MHCs. The bag2 and chain fibers contained all three M‐band proteins, whereas the bag1 fibers contained only myomesin. In general the MHC expression in the human masseter intrafusal fiber types was similar to that previously reported for limb muscles in man as well as for limb and masseter muscles in other species. However, the number of intrafusal fibers per spindle was unusually high (up to 36). This reinforces the idea that masseter muscle spindles have a strong proprioceptive impact during the control of jaw movements. © 1994 John Wiley & Sons, Inc.
Multifocal cytomegalovirus demyelinative polyneuropathy associated with AIDS
Authors: Morgello Susan , Simpson David M.
Published: January 2005

A 47‐year‐old man with acquired immunodeficiency syndrome presented 3 months antemortem with the onset of lower extremity sensory abnormalities. A progressive course of multifocal weakness and sensory disturbances ensued. Electrophysiologic studies revealed a generalized asymmetric demyelinating polyneuropathy with secondary axonal loss. The patient was sequentially treated with plasmapheresis, high dose corticosteroids, intravenous immune globulin, and ganciclovir. His neuropathy progressed, and he died of a fulminant bronchopneumonia. At autopsy the patient had a multifocal cytomegalovirus polyradiculoneuropathy, with both demyelinative and necrotizing features. While cytomegalovirus may be associated with a variety of peripheral nerve syndromes, its clinical presentation as a primary demyelinating polyneuropathy is unusual. Its importance vis‐à‐vis potential therapy for AIDS‐associated neuropathies is discussed. © 1994 John Wiley & Sons, Inc.
Human myoblast transplantation in immunodeficient and immunosuppressed mice: Evidence of rejection
Authors: Huard Johnny , Roy Raynald , Guérette Benoît , Verreault Steeve , Trèmblay Genevieve , Tremblay Jacques P.
Published: January 2005

Normal human myoblasts were cloned and transplanted in the tibialis anterior of immunodeficient nude and SCID mice and in mdx mice under different immunosuppressive treatments (cyclosporine A, CsA; antilymphocyte serum, ALS) or not immunosuppressed. This permitted us to show the interaction of the immune system in the myoblast transplantation. The graft success was assessed by verifying signs of humoral and cellular immune reactions and the presence of dystrophin produced by the fusion of the donor myoblasts. This study showed that clones of human myoblasts were able to fuse and produce dystrophin in injected muscles of immunodeficient mice and mdx mice receiving an effective immunosuppressive treatment (i.e., ALS + CsA). However, the same pool of human myoblasts injected in mdx mice inadequately immunosuppressed (i.e. CsA alone or ALS alone) triggered an immune reaction and was rejected. Cells expressing CD4 and CDS antigens were observed in the injected muscles of mice treated with CsA alone. Therefore, evidence of humoral and cellular rejection was observed following human myoblast transplantation. © 1994 John Wiley & Sons, Inc.
Skeletal muscle mitochondrial myopathy as a cause of exercise intolerance in a horse
Authors: Valberg Stephanie J. , Carlson Gary P. , Cardinet George H. , Birks Eric K. , Jones James H. , Chomyn Anne , DiMauro Salvatore
Published: January 2005

Although exertional myopathies are commonly recognized in horses, specific etiologies have not been identified. This is the first report in the horse of a deficiency of Complex I respiratory chain enzyme associated with profound exercise intolerance. Physical examination, routine blood tests, endoscopy, and ultrasonograms of the heart and iliac arteries were unremarkable. With slow, incremental exercise (speeds 1.5–7 m/s), the Arabian mare showed a marked lactic acidosis, increased mixed venous PVO2, and little change in oxygen consumption. Muscle biopsies contained large accumulations of mitochondria with bizarre cristae formations. Biochemical analyses revealed a very low activity of the first enzyme complex in the mitochondrial respiratory chain (NADH CoQ reductase). The exercise intolerance and muscle stiffness in this horse were attributed to a profound lactic acidosis resulting from impaired oxidative energy metabolism during exercise. © 1994 John Wiley & Sons, Inc.
Dual‐energy X‐ray absorptiometry in neuromuscular diseases
Authors: Kanda Fumio , Fujii Yoshio , Takahashi Keiichi , Fujita Takuo
Published: January 2005

Body components were measured noninvasively in patients with neuromuscular disease by using dual‐energy X‐ray absorptiometry (DXA), capable of separately analyzing fat, bone, and muscle content. In all patients with muscle atrophy of myogenic or neurogenic origin, muscle mass was markedly reduced. Although all three components (fat, muscle, and bone) were decreased in neurogenic atrophy patients, fat mass alone was increased significantly in myogenic atrophy patients. The fat/muscle ratio (f/m) was significantly higher in myogenic atrophy patients than in the normal controls and neurogenic atrophy patients. The higher f/m ratio in myogenic atrophy patients seems to reflect a marked fat infiltration into atrophied skeletal muscles of patients with primary muscular disease. Using DXA, it is possible to distinguish clearly between myogenic atrophy from neurogenic atrophy, opening the way to an evaluation of the severity of quantitative and qualitative muscle changes in neuromuscular disease. © 1994 John Wiley & Sons, Inc.
Sensory thresholds in older adults: Reproducibility and reference values
Authors: de Neeling J. Nico D. , Beks Pieter J. , Bertelsmann Frits W. , Heine Robert J. , Bouter Lex M.
Published: January 2005

To evaluate the test–retest reproducibility of vibratory perception (VPT) and thermal discrimination (TDT) thresholds on the foot in older adults, we examined 20 50–76‐year‐old subjects with, and 19 without noninsulin‐dependent diabetes mellitus. Adjusted reference values for both thresholds were obtained by assessing the relations with age, body height, and sex among 216 subjects with normal glucose tolerance, of the same age, sampled randomly from a geographically defined general population. The VPT appeared to be more reproducible than the TDT (reliability coefficient 0.89 vs. 0.54). The reproducibility of the VPT was inversely related to age and better for men than for women. Diabetes and glycemic level did not affect the reproducibility of either threshold. Both thresholds were related to age and height. Women had a higher VPT than men. The relations between sex and sensory thresholds at the lower limb, reported in previous studies, were probably confounded by height. © 1994 John Wiley & Sons, Inc.
Parvalbumin immunocytochemistry and calcium deposition in muscle fiber necrosis and subsequent regeneration following intramuscular injection of metoclopramide
Authors: Olive Montserrat , Rivera Rosa , Ferrer Isidro
Published: January 2005

We have studied the sequential change of parvalbumin immunocytochemistry and its correlation with intracellular Ca242+ deposition in an animal model of muscle fiber necrosis and regeneration induced by intramuscular injection of metoclopramide. Twenty‐four hours after the drug's injection, extensive muscle fiber necrosis, together with dramatic loss of parvalbumin immunoreactivity and intracellular Ca2+ deposition, was observed. Muscle fiber regeneration began on day 4 after the injection and was complete by the end of the third week. Parvalbumin was not detected in the regenerating fibers, but gradually emerged during the second week as muscle fibers increased in size. It can be suggested that loss of parvalbumin in necrotic fibers is secondary to the loss in integrity of the sarcolemma. Alternatively, loss of parvalbumin in degenerating fibers may impair calcium buffering and act as a contributory factor in the necrotic process. The progressive appearance of parvalbumin immunoreactivity in regenerating fibers parallels that found in normal myogenesis. © 1994 John & Sons, Inc.
The relationship between body mass index and the diagnosis of carpal tunnel syndrome
Authors: Werner Robert A. , Albers James W. , Franzblau Alfred , Armstrong Thomas J.
Published: January 2005

Increased weignt and, more recently, body mass index (BMI), have been suggested as risk factors for carpal tunnel syndrome (CTS). In an effort to determine the relative risk (RR) of obesity in the development of CTS, 949 patients who had an evaluation of the right upper extremity that included motor and sensory conduction studies of the median and ulnar nerves were reviewed. Of these patients, 261 were diagnosed with a median mononeuropathy at the wrist. Those individuals who were classified as obese (BMI > 29) were 2.5 times more likely than slender individuals (BMI < 20) to be diagnosed with CTS. Forty‐three percent of obese women and 32% of obese men had the diagnosis of CTS compared to 21% of slender women and 0% of slender men. © 1994 John Wiley & Sons, Inc.
Familial amyloid polyneuropathy in Taiwan: Identification of transthyretin variant (Leu55 → Pro)
Authors: Yamamoto Kanji , Hsu Shih‐Pin , Yoshida Kunihiro , Ikeda Shu‐ichi , Nakazato Masamitsu , Shiomi Kazutaka , Cheng Shaw‐Yi , Furihata Kenichi , Ueno Ichiro , Yanagisawa Nobuo
Published: January 2005

We report a family with familial amyloid polyneuropathy (FAP), showing an early‐onset and a fatal outcome before age 30. Transthyretin (TTR) gene analysis showed one point mutation (T → C change) in the second base of codon 55, and the corresponding amino acid substitution of proline (Pro) for leucine (Leu) was confirmed at the protein level. This is the first FAP family of Taiwanese origin demonstrating a causative gene abnormality, and FAP with TTR‐Pro55 was considered to be more serious compared with other forms of FAP. © 1994 John Wiley & Sons, Inc.
Suppression and long latency excitation of single spinal motoneurons by transcranial magnetic stimulation in health, multiple sclerosis, and stroke
Authors: Boniface S. J. , Schubert M. , Mills K. R.
Published: January 2005

Whether or not suppression at the level of the spinal motoneuron plays a role in motor deficits such as central paresis is unknown. In this study suppression in the firing of tonically active low threshold single motoneurons following low intensity transcranial magnetic stimulation is described in health and disease. Changes in firing probability in the absence of an early excitatory response were studied in a total of 14 motor units from 4 healthy subjects, 5 patients with multiple sclerosis, and 1 patient with stroke. Firing probability began to fall 18–59 ms after the stimulus and remained low for a period of 27–133 ms. There were no obvious differences between the three subject groups. The change in firing probability was not associated with specific physical signs. Late rises in firing probability were seen in 7 of the 14 motor units at latencies that were similar to the secondary peak which is known to occur with higher stimulus intensities. It is argued that the mechanism of partial suppression is not dependent on the full integrity of the pyramidal tract and is likely to involve a transient withdrawal of descending excitatory drive rather than an inhibitory postsynaptic potential at the spinal motoneuron. © 1994 John Wiley & Sons, Inc.
Prolonged paralysis due to nondepolarizing neuromuscular blocking agents and corticosteroids
Authors: Barohn Richard J. , Jackson Carlayne E. , Rogers Susan J. , Ridings Larry W. , McVey April L.
Published: January 2005

The long‐term use of nondepolarizing neuromuscular blocking agents (ND‐NMBA) has recently been implicated as a cause of prolonged muscle weakness, although the site of the lesion and the predisposing factors have been unclear. We report 3 patients (age 37–52 years) with acute respiratory insufficiency who developed prolonged weakness following the discontinuation of ND‐NMBAs. Two patients also received intravenous corticosteroids. Renal function was normal but hepatic function was impaired in all patients, and all had acidosis. Electrophysiologic studies revealed low amplitude compound motor action potentials, normal sensory studies, and fibrillations. Repetitive stimulation at 2 Hz showed a decremental response in 2 patients. The serum vecuronium level measured in 1 patient 14 days after the drug had been discontinued was 172 ng/mL. A muscle biopsy in this patient showed loss of thick, myosin filaments. The weakness in these patients is due to pathology at both the neuromuscular junction (most likely due to ND‐NMBA) and muscle (most likely due to corticosteroids). Hepatic dysfunction and acidosis are contributing risk factors. © 1994 John Wiley & Sons, Inc.
Reference values of motor unit action potentials obtained with multi‐MUAP analysis
Authors: Bischoff Christian , Stålberg Erik , Falck Björn , Eeg‐Olofsson Karin Edebol
Published: January 2005

We collected reference values of motor unit action potentials (MUAPs) from healthy deltoid, brachial biceps, first dorsal interosseous, lateral vastus, and anterior tibial muscles in 105 subjects between 15 and 86 years. The MUAPs were recorded with a concentric needle electrode and extracted with a decomposition method we call multi‐MUAP analysis. The main goal is to identify and extract MUAPs. Also, the firing pattern of the motor units can be followed. No significant changes with age were found for duration, spike duration, thickness, amplitude, area, size index, or number of phases in all muscles studied. We did not find any influence of gender or height. We found higher amplitudes and shorter durations compared with previous studies. This may be due to a higher contraction level that can be used with a decomposition technique. No right‐left side differences were found. The coefficient of variation of the parameters in repeated examinations was small, which implies a good reliability of the measurements. Interexaminer variability of four investigators was not greater than in repeated studies. © 1994 John Wiley & Sons, Inc.
Muscle fiber conduction velocity in the diagnosis of familial hypokalemic periodic paralysis—invasive versus surface determination
Authors: van der Hoeven J. H. , Links T. P. , Zwarts M. J. , van Weerden T. W.
Published: January 2005

Muscle fiber conduction velocity (MFCV) in the brachial biceps muscle was determined in a large family of patients with hypokalemic periodic paralysis (HOPP) by both a surface and an invasive method. Other surface EMG parameters and the muscle force were also determined. Both the surface and the invasive method showed a significantly lower mean MFCV in the proven gene carriers but only the invasive method showed a lower MFCV in all proven carriers. It can be concluded that MFCV determination is a reliable method to detect the membrane defect in HOPP carriers and that the invasive method is not only easy to perform, but also more sensitive. The muscle force and the integrated EMG at maximal voluntary contraction were lower in the carrier group. A positive correlation between the surface MFCV and the neuromuscular efficiency (the quotient of force and integrated EMG) was found in the controls but not in the HOPP carriers. Since type II fibers have a higher neuromuscular efficiency, this suggests a preferential involvement of type II fibers in HOPP. © 1994 John Wiley & Sons, Inc.