bluuebunny/crossref_metadata_2025_split huggingface dataset:
Distant effects of locally injected botulinum toxin: A double‐blind study of single fiber EMG changes
Authors: Lange Dale J. , Rubin Michael , Greene Paul E. , Kang Un J. , Moskowitz Carol B. , Brin Mitchell F. , Lovelace Robert E. , Fahn Stanley 
Published: January 2005

AbstractWe used single fiber electromyography (SFEMG) to study 42 patients who had enroleld in a double‐blind, placebo‐controlled trial undertaken to assess the efficacy of botulinum toxin (BTX) injection of neck muscles to treat torticollis. SFEMG in a limb muscle was performed before treatment, 2, and 12 weeks after injection of placebo or BTX. Before treatment, the mean jitter was 26.8 μsec in patients who were to receive BTX, and 25.7 μsec in the placebo group. Two weeks after injection, mean jitter in the group receiving BTX was 43.6 μsec. In the placebo group, it was 26.5 μsec (P = <.05). Twelve weeks after injection, mean jitter in the BTX group was 35.5; for the placebo group it was 24.5. Fiber density did not change in any patient during the study. There were no remote clinical effects of BTX. Injection of BTX into muscles affected with focal dystonia is a promising and safe treatment, but there are subclinical effects on uninjected muscles.
Large amplitude sensory action potentials in myelopathy: An observation
Authors: Pullman Seth L. , Rubin Michael 
Published: January 2005

AbstractSubjects with at least one sensory action potential (SAP) amplitude greater than 2 SD above the age‐matched mean during standard nerve conduction tests were evaluated for evidence of spinal cord disease. From a total of 153 subjects, 16 had at least one large amplitude SAP and 12 of 16 (75%) had a documented myelopathy. While a mechanism has yet to be determined, this observation suggests that SAP amplitudes greater than 2 SD above normal may be correlated with clinical evidence of injury to the central nervous system.
AAEM minimonograph #14: The influence of temperature in clinical neurophysiology
Authors: Denys Eric H. 
Published: January 2005

AbstractAAEM MINIMONOGRAPH #14Temperature affects biologic and neurophysiologic processes and is, therefore, always well controlled in in vitro experiments. Its role is equally important in the clinical laboratory but has often been neglected. Lower temperatures cause slower nerve conduction velocities (NCVs), and increased amplitudes of muscle and nerve potentials. Fibrillations may disappear, and muscle contraction will be slower and weaker. Neuromuscular transmission improves. Somatosensory evoked potentials (SEPs) are similarly vulnerable in the peripheral segments, or with changes in central temperature. As a result, abnormalities are artificially created or existing defects are not detected, resulting in false or missed diagnoses. Control of temperature, albeit somewhat time consuming, will result in greater diagnostic accuracy.
Use of a catchlike property of human skeletal muscle to reduce fatigue
Authors: Binder‐Macleod Stuart A. , Barker Charles B. 
Published: January 2005

AbstractThis study compared the force output produced by variable frequency, short‐duration trains (VFTs) of electrical pulses with the forces produced by constant frequency, short‐duration trains (CFTs). Human quadriceps femoris muscle was stimulated with a 300‐msec train of pulses once every second for 180 seconds. Each subject (n = 12) participated in 4 randomly assigned experimental sessions. During 3 sessions, a CFT of 80, 40 or 20 pps was used. During a fourth session, a VFT, which consisted of all 3 of the above frequencies, was used. The force at 100 msec, average force of each contraction and peak force were calculated for every 30th contraction. By the 90th contraction, the force at 100 msec and the average force were significantly greater for the VFT than for each CFT. Thus, the VFT, by using a catchlike property, may provide significant advantages over any CFT when using electrical stimulation for functional electrical stimulation.
Far‐field potentials in muscle
Authors: Dumitru Daniel , King John C. 
Published: January 2005

AbstractFar‐field potentials have been predicted by computer simulations as well as demonstrated in both animals and humans with respect to the peripheral and central nervous systems. Computer simulations have also predicted far‐field potentials originating at the termination of muscle tissue. This investigation demonstrates the occurrence of 2 far‐field potentials in the human biceps muscle resulting from action potential termination at the musculotendonous junctions. A monophasic potential is produced at both the muscle's origin and insertion, and the polarity is entirely dependent upon the recording montage. Sequential stimulation of the biceps muscle at 2.5‐cm increments resulted in the 2 far‐field potentials and their respective latencies changing proportional to the distance between the stimulus site and the 2 musculotendonous junctions. Various stimulation and recording montages are used to investigate the properties of these far‐field potentials. The leading/trailing dipole model is utilized to explain the production and polarity of far‐field potentials generated by muscle tissue.
Axonal damage in Guillain‐Barré syndrome
Authors: Van Der Meché Frans G. A. , Meulstee Jan , Kleyweg Ruud P. 
Published: January 2005

AbstractIn Guillain‐Barré syndrome patients, severe axonal degeneration occasionally occurs, often resulting in permanent functional deficit. In order to assess the development of axonal degeneration, we followed a consecutive series of 42 patients longitudinally using clinical and neurophysiological methods. Eight patients were considered to have severe axonal degeneration: in these patients denervation potentials were eventually found and at least 1 nerve proved inexcitable, and clinical recovery was slow and incomplete. Five of these 8 patients initially showed a pronounced generalized conduction block, the physiological hallmark of demyelination, before signs of axonal degeneration developed. In the remaining three patients, the first evaluation revealed low amplitudes with only modest conduction block; this is consistent with predominantly distal demyelination, but might, alternatively, be explained by primary axonal degeneration. Caution is necessary in using distal CMAP parameters for prognostic purposes, because the distal CMAP may be relatively spared in the early phase of the disease despite severe axonal degeneration later.
Autonomic function in hereditary motor and sensory neuropathy (charcot‐marie‐tooth disease)
Authors: Ingall Timothy J. , McLeod James G. 
Published: January 2005

AbstractAutonomic tests of heart rate and blood pressure control using both invasive and noninvasive techniques were performed on 11 patients with hereditary motor and sensory neuropathy (HMSN) types 1, and 4 patients with HMSN type 2. The results were compared with those of 76 control subjects. No significant difference was found between the patient and control groups. Impairment of sweating on the extremities was found in patients with HMSN types 1 and 2, consistent with distal degeneration of sympathetic fibers in peripheral nerves, but there were no abnormalities of cardiovascular reflex control mechanisms.
Stimulated single‐fiber electromyography in lambert‐eaton myasthenic syndrome
Authors: Chaudhry Vinay , Watson Danny F. , Bird Shawn J. , Cornblath David R. 
Published: January 2005

AbstractThe Lambert‐Eaton myasthenic syndrome (LEMS) is an autoimmune disorder of neuromuscular transmission. Electrodiagnosis is confirmed by an increase in compound muscle action potential amplitude during high‐frequency repetitive nerve stimulation or following brief exercise. We describe the results of stimulated single‐fiber electromyography in 4 patients with disorders of neuromuscular transmission: LEMS (2), LEMS/myasthenia gravis (MG) overlap (1), and MG (1). Stimulated SFEMG was performed in the extensor digitorum communis muscle with axonal intramuscular suprathreshold stimulation at low and high rates. In all 4 patients, a rate dependence of jitter was found. In LEMS and LEMS/MG, jitter and blocking improved with high stimulation rates, as compared with the opposite effect in MG. We conclude that stimulated SFEMG is a valuable technique in the diagnosis of LEMS.
Class II MHC antigens in normal human skeletal muscle
Authors: Cifuentes‐Diaz Carmen , Delaporte Christine , Dautréaux Brigitte , Charron Dominique , Fardeau Michel 
Published: January 2005

AbstractClass II MHC antigen expression has been investigated in muscle tissue and cultured cells from normal human skeletal muscle by light and electron immunocytochemistry. In muscle tissue, these antigens were detected in satellite cells, interstitial cells, and blood vessels. In cultures, muscle cells were stained with a pan‐reactive anti‐HLA class II antibody and with isotypes specific for DP, DQ, and DR. The staining was present on mononucleated cells and persisted on myotubes; it was stronger for DR and DQ isotypes than for DP. At the subcellular level, staining was located not only at the cell surface, but also next to the endoplasmic reticulum and in the cytosol. Thus, myosatellite cells and aneurally cultured cells from human normal skeletal muscle express class II MHC antigens. Moreoever, the myotube staining and the presence of gold particles inside the cells suggested synthesis of these antigens after myoblast fusion.
Muscle fatigue measured with evoked muscle vibrations
Authors: Barry Daniel T. , Hill Timothy , Im Dukjin 
Published: January 2005

AbstractSkeletal muscle vibrates laterally during voluntary and evoked muscle contractions. We hypothesized that the vibration amplitude from evoked muscle twitches is directly related to evoked twitch force from fatiguing muscle. To test the hypothesis, vibrations produced by evoked muscle twitches were recorded during short (5‐second) rest periods as the muscle was intermittently exercised with voluntary contractions. Trials were performed at 30%, 50%, and 70% of maximal coluntary contraction. Evoked muscle twitches eliminated the problems of motivation and tremor that complicatye sound and vibration measurements during voluntary contractions. Results from the first dorsal interosseus hand muscle in 11 normal adult volunteers from the first dorsal interosseus hand muscle in 11 normal adult volunteers revealed that the vibration amplitude is highly correlated (r2 = 0.93, at 70% MVC, r2 = 0.97, at 50% MVC; r2 = 0.85, at 30% MVC) with force. Both potentiation and reduction of force with exercise were accompanied by parallel changes in vibration amplitude, as measured with an accelerometer. Compound muscle action potentials did not increase with exercise‐induced twitch potentiation, and did not correlate as highly with force during fatigue.
Muscle energy metabolism in female DMD/BMD carriers: A 31P‐MR spectroscopy study
Authors: Barbiroli Bruno , Funicello Rosanna , Ferlini Alessandra , Montagna Pasquale , Zaniol Paolo 
Published: January 2005

Abstract31P nuclear magnetic resonance spectroscopy (31P‐MRS) was used to investigate the energy metabolism of the gastrocnemius muscle in 16 DMD/BMD female carriers. No significant difference was found with the controls in the resting muscle, while all carriers showed a decreased ability to perform work, and a higher Pi/PCr ratio for comparable relative levels of steady‐state work. The rate of postexercise recovery of PCr/Pi ratio was lower in all carriers. The decreased rate of PCr/Pi recovery appears to be mainly due to a decreased rate of Pi recovery. Our findings show abnormal muscle energy metabolism in DMD/BMD female carriers.
X‐linked recessive Charcot–Marie‐Tooth neuropathy: Clinical and genetic study
Authors: Ionasescu Victor V. , Trofatter James , Haines Jonathan L. , Summers Anne M. , Ionasescu Rebecca , Searby Charles 
Published: January 2005

AbstractWe describe three families with X‐linked recessive Charcot–Marie–Tooth (CMT) neuropathies. The disease phenotype in family 1 was characterized by infantile onset, weakness of lower legs, areflexia, pes cavus, and mental retardation (2 of 5 patients). The disease phenotype in families 2 and 3 was characterized by late onset, distal weakness, and normal intelligence. Hereditary spastic paraparesis was also present in the CMT patients of family 2. Thirty X‐linked DNA markers were used for linkage studies. A maximum lod score of +3.48 was obtained by multipoint linkage analysis for the DXS16 locus mapped at Xp22.2 in family 1. In families 2 and 3, there was suggestion of linkage of Xq26 markers; the peak mutlipoint lod score for these 2 CMT families was 1.81, at DXS144. These results were suggestive of heterogeneity. The joint analysis including both regions (Xp22.2 and Xq26) provided evidence against homogeneity (χ2 = 9.12, P < 0.005).
Dantrolene sodium and fatigue of long duration
Authors: Moussavi Robabe S. , Lehman Steven L. , Miller Robert G. 
Published: January 2005

AbstractA long‐lasting imparment of muscular force generation follows fatiguing exercise (fatigue of long duration), the physiological basis of which is not well understood. To investigate the role of reduced calcium release in longlasting fatigue, we examined the effects of dantrolene sodium, which selectively decreases calcium release from the sarcoplasmic reticulum. The drug impaired muscle function in a pattern identical to that of long‐lasting fatigue. The results are consistent with either indeependent effects of dantrolene and exercise at the same site in the excitation–contraction coupling chain, or independent actions at separate serial sites.
Adverse effect of verapamil in myasthenia gravis
Authors: Swash Michael , Ingram David A. 
Published: January 2005

AbstractVerapamil, a class IV anti‐arrhythmic drug that blocks voltage‐dependent calcium channels in cardiac and smooth muscle, also has effects on presynaptic and postsynaptic voltage‐dependent calcium channels at the neuromuscular junction. In a postoperative patient with pre‐existent myasthenia gravis, oral verapamil caused a marked exacerbation in myasthenic weakness.
Jitter of the stimulated motor axon
Authors: Trontelj Jože V. , Stålberg Erik , Mihelin Marjan , Khuraibet Adnan 
Published: January 2005

AbstractElectrical microstimulation of motor axons in conjunction with single fiber EMG (SFEMG) is increasingly used to measure the jitter of the motor endplates. This study examines the jitter of the stimulation site on the axon when stimulus strength is at threshold. In the absence of spurious blocking, this was found to be 5 µs on the average. With intermittent blocking, however, a mean additional jitter of 40 µs was obtained. The latter is considered to result from changing propagation velocity in the muscle fiber due to irregularity of activation rate. In clinical jitter studies, inadvertent threshold stimulation can result in significant error when associated with intermittent blocking.
Modulation of soleus H reflex by lateral tilting in man
Authors: Aiello I. , Rosati G. , Sau G. F. , Cacciotto R. , Lentinu M. E. , Tidore B. , Traccis S. 
Published: January 2005

AbstractStatic vestibular infuences on extensor tone of the lower limbs in man were studied by analyzing the changes in right soleus H‐reflex (RSHR) area in relation to lateral titings. Eight normal asult volunteers were tested in an experimental situation designed to minimize all afferent inputs, except the vestibular ones. Each subject was seated on a chair which could be tited laterally from the vertical to both sieds. Lateral titings were applied at a random order from the vertical (0° control position) to 4°, 8°, 12°, 16°, and 20°, of both sides (test positions). The results showed inhibtion in SHR area of the leg ipsilateral to the titing and facilitation of the contralateral SHR. These data indicate that, in man as in the decerebrate cat, tonic labyrinth reflexes act asymmetrically and that, in static condition, the vestibular syseral perturbation of upright position.
Localization of protein kinase C in human skeletal muscle
Authors: Nakano Satoshi , Shimohama Shun , Saitoh Tsunao , Akiguchi Ichiro , Kimura Jun 
Published: January 2005

AbstractThe immunolocalization of protein kinase C (PKC) isozymes α, βI, and βII, was investigated in human skeletal muscle. All three isozymes were present on the muscle fiber surface membrane and within the muscle fibers. The α‐isozyme was most clearly delineated on the surface membrane of the muscle fiber and on small blood vessels in the connective tissue. The axons of myelinated intramuscular nerves stained intensely for the βI isozyme, whereas the endoneurial connective tissue reacted more strongly for the α‐ and βII‐isozymes. PKC isozymes may regulate intracellular signal transduction in human skeletal muscle, as in the other tissues. but their exact role in muscle remains unknown.
Human myoblast transplantation: Preliminary results of 4 cases
Authors: Huard J. , Bouchard J. P. , Roy R. , Malouin F. , Dansereau G. , Labrecque C. , Albert N. , Richards C. L. , Lemieux B. , Tremblay J. P. 
Published: January 2005

AbstractMyoblasts from immunocompatible donors have been transplanted into the muscles (tibialis anterior, biceps brachii, and/or extensor carpi radialis longus) of 4 Duchenne patients in the advanced stages of the disease. Although no immunosuppressive treatment was used, none of the patients showed any clinical signs of rejection such as fever, redness, and inflammation. One patient transiently produced antibodies against the donor myoblasts as determined by cytofluorometric analysis. This patient and 2 others were shown to form antibodies against their donor's myotubes. Muscle biopsies of the injected tibialis anterior of 4 patients revealed that 80%, 75%, 25% and 0% of the muscle fibers, respectively, showed some degree of dystrophin immunostaining, The contralateral noninjectd muscles of the latter 3 patients did not contain any dystrophin positive fibers, while that of the first patient showed dystrophin expression in 16% of the fibers examined. Myoblasts were also injected into the extensor carpi radialis longus or the biceps brachii of these patients. A few months subsequent to injection, one patient was shown to have a 143% increase of strength during static wrist extension. This result must be interpreted with caution because a double‐blind strength‐measuring protocol was not used. Furthermore, we have noted that this change slowly decayed over time. The strength of 2 other patients was increased less remarkably (41% and 51%), while the strength of the fourth patient was unchanged.
Eosinophilia–myalgia syndrome: Myopathic electrodiagnostic characteristics
Authors: Tanhehco Justina L. , Wiechers David O. , Golbus Joseph , Neely Sarah E. 
Published: January 2005

AbstractEosinophilia–myalgia syndrome (EMS) is disorder characterized by generalized muscle pain and eosinophilia. The etiology of this syndrome appears to be related to the ingestion of L‐tryptophan. Most studies to date describe an associated peripheral neuropathy or combined myopathy and peripheral neuropathy. This report presents 2 EMS patients with myopathy, confirmed by muscle biopsy in 1 case and electrophysiology in both cases. No clinical evidence of neuropathy was found. Both routine and single fiber electromyography failed to demonstrate abnormalities, suggesting neuropathy. Electrodiagnostic abnormalities paralleled the clinical course. After 10 months, both patients continued to have symptoms of muscle cramping and reduced endurance, with mild electromyographic abnormalities, perhaps reflecting changes in their motor unit.
Median–ulnar nerve communications and anomalous innervation of the intrinsic hand muscles: An electrophysiological study
Authors: Amoiridis Georgios 
Published: January 2005

AbstractOne hundred (100) left arms were examined for median‐to‐ulnar or ulnar‐to‐median nerve anastomoses using surface electrodes. Muscles innervated by the anastomosis were determined using a concentric needle electrode. We found a motor median‐to‐ulnar nerve anastomosis in the forearm in 32% of the cases (Martin–Gruber anastomosis, MGA). No case of motor ulnar‐to‐median nerve anastomosis in the forearm could be found. The MGA mainly innervated muscles, which are normally supplied by the ulnar nerve. The high incidence of MGA in this study shows that all clinically relevant motor median‐to‐ular nerve communications in the forearm can be detected using surface electrodes in routine examinations. Stimulus spread must be looked for and eliminated by the methods described.
Neuromuscular causes of prolonged ventilator dependency
Authors: Spitzer A. Robert , Giancarlo Thomas , Maher Leo , Awerbuch Gavin , Bowles Alvin 
Published: January 2005

AbstractWe prospectively evaluated 21 patients with prolonged ventilator dependency, to determine the frequency of unsuspected neuromuscular disease as a cause of this condition, and to determine the types of such diseases. Assessment was performed with routine and specialized electrophyiologic procedures. None of the patients had known prior neuromuscular disease, and none of had ongoing medical problems that could account for their continued ventilator dependency. Sixty‐two precent were found to have a neuromuscular disease severe enough to account for the ventilator dependency. Most of the remaining cases had a contributory neuromuscular disease. In addition to critical illness polyneuropathy, several other significant categories were identified. Myopathic EMG changes were found in 50% of the subgroup assessed by quantitative EMG. We conclude that neuromuscular disease is the most important factor in prolonged ventilator dependency, and that disease other than critical illness polyneuropathy represent an important cause of this syndrome.
Modeling fiber type grouping by a binary markov random field
Authors: Venema Henk W. 
Published: January 2005

AbstractA new approach to the quantification of fiber type grouping is presented, in which the distribution of histochemical type in a muscle corss section is regarded as a realization of a binary Markov random field (BMRF). Methods for the estimation of the parameters of this model are discussed. The first order BMRF, which is used in this article, contains 2 parameters: α and β. The parameter β is of prime importance, as it is an interaction parameter which governs the degree of type grouping. The value of this parameter is estimated for 9 muscle biopsies. The interpretation of the results is discussed.
Dominantly inherited malignant hyperthermia (MH) in the King–Denborough Syndrome
Authors: Isaacs Hyam , Badenhorst Margaret E. 
Published: January 2005

AbstractA 14‐year‐old boy, an only child, with the phenotypical dysmorphic features of the King–Denborough Syndrome developed a severe hyperthermic episode during anesthesia which responded to the administration of sodium dantrolene. As adequate metabolic studies were not available at the time of the crisis he was referred for confirmation of the malignant hyperthermia (MH) status. Muscle tension studies confirmed the presence of MH. The patient's mother and father were subsequently tested and the mother was found to be MH positive, the father MH negative.
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

AbstractWe 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.