bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thyrotoxic periodic paralysis and the sodium/potassium pump
Authors: Marx Alexander , Ruppersberg Johann Peter , Pietrzyk Christian , Rüdel Reinhardt 
Published: January 2005

AbstractThe hypothesis of altered Na+/K+ transport in thyrotoxic periodic paralysis (TPP) was tested in an investigation of the K+ influx into erythrocytes from two patients with episodes of thyrotoxic muscle weakness. A patient with primary hypokalemic periodic paralysis (HPP) and three healthy volunteers served as controls. The TPP patients were of Oriental and Caucasian origin and differed in their clinical symptoms. For the Caucasian patient, the Na+ content of the erythrocytes was twice the control, for the Oriental patient it was normal. The K+ dependence of the ouabain‐inhibitable K+ influx (the pump action) was also abnormal in the Caucasian patient, the flux being 70% of control at 2 mM [K+]e and normal at 4 mM[K+]e. The K+ influx was normal in the Oriental patient. By contrast, the K+ leak of the cells was normal in the Caucasian and was increased in the Oriental patient. The pump/leak ratio was thus reduced in both TPP patients. All parameters investigated were normal in the patient with primary HPP. It is concluded that the ion transport systems of muscle may be altered in TPP, but that the pathomechanism might be different in the rare Caucasian cases and the rather more common Oriental cases.
Immunohistochemical differential distribution of S‐100α and S‐100β in the peripheral nervous system of the rat
Authors: Sugimura Kimiya , Haimoto Hajime , Nagura Hiroshi , Kato Kanefusa , Takahashi Akira 
Published: January 2005

AbstractThe localization of the α subunit of the S‐100 protein (S‐100α) and β subunit (S‐100β) was studied in the peripheral nervous system of the rat. In peripheral nerves, S‐100α and S‐100β were found in the cytoplasm of Schwann cells. Axons were positively stained in part by S‐100α and almost totally by S‐100β. In the dorsal root ganglia, S‐100β was found in satellite cells and their processes and in some neurons. S‐100β was found in more of the large neurons, but almost all of the small neurons were negative for S‐100β. In the anterior horn cells, S‐100β staining was stronger than that of S‐100β. In Schwann cells, both S‐100β and S‐100β were present on the rough endoplasmic reticulum, free ribosomes, and nucleus, as seen by electron microscopy. The S‐100α and S‐100β in axons were associated with microtubules and neurofilaments.
Distribution of nerve conduction velocities in acute thallium poisoning
Authors: Yokoyama Kazuhito , Shunichi Araki , Abe Haruo 
Published: January 2005

AbstractTo assess the effects of thallium on the conduction velocities of faster and slower nerve fibers, the distribution of conduction velocities in sensory fibers of the median nerve was examined in a patient with acute thallium poisoning 2 and 11 months after the onset of symptoms. In the first examination, the patient showed evidence of a distal sensorimotor neuropathy and had an elevated urinary thallium concentration (3.5 mg/L); the conduction velocities of faster fibers were below the normal lower limit, whereas those of slower fibers were within normal limits. At the second examination, the conduction velocities of all faster and slower fibers increased and were within normal limits: clinical signs and symptoms of neuropathy almost disappeared. It is concluded that the conduction velocities of faster fibers significantly decrease in an early stage of acute thallium poisoning and recover following recuperation from the poisoning; those of slower fibers are minimally affected and then improve.
Cortical magnetic stimulation in amyotrophic lateral sclerosis
Authors: Eisen Andrew , Shytbel Wayne , Murphy Kirsten , Hoirch Maureen 
Published: January 2005

AbstractForty patients with ALS underwent cortical magnetic stimulation. Twelve had marked pseudobulbar signs; in these motor evoked potentials (MEPs) could not be elicited. Mean MEP latencies in the others, who had predominantnantly lower motor neuron signs, measured 23.3±2.1 msec (thenar), 18.7±5.3 msec (EDC), and 13.4±2.9 msec (biceps), respectively. These values were significantly longer (P > 0.001) compared with normal values (n=35), which measured 20.2±1.6, 14.2±1.7, and 9.4±1.7 msec, respectively. MEP amplitude was often markedly reduced (less than 15% of the M wave) compared with a normal mean of 39.5±13.0%. Overall abnormal MEPs (delayed, absent, or reduced in amplitude) approached 100%. It is argued that measuring central motor delay, which was not significantly different in the patients compared with normals, is subject to error in ALS.
Familial hypertrophic cardiomyopathy and muscle carnitine deficiency
Authors: Bautista J. , Rafel E. , Martinez A. , Sainz I. , Herrera J. , Segura L. , Chinchon I. 
Published: January 2005

AbstractFive members of the same family, along three generations, presented with hypertrophic cardiomyopathy. Neurological examination, muscle strength, electromyography, and serum creatine kinase were normal. Skeletal muscle biopsy showed abnormal lipid accumulation and carnitine deficiency. In three patients the cardiac symptoms and echocardiographic findings improved after treatment withL‐carnitine, 3–4 g daily, and a long‐chain fattyacid‐free diet.
Resealed fiber segments for the study of the pathophysiology of human skeletal muscle
Authors: Lehmann‐Horn Frank , Iaizzo Paul A. 
Published: January 2005

AbstractThe usefulness of long fiber segments for the study of the pathophysiology of human skeletal muscle was evaluated. Immediately after biopsy, the fiber segments were depolarized. Within 3 hours the cut ends resealed, and if the segments were ≥ ‐ 2.5 cm long they regained normal resting membrane potentials (i.e., negative to −80 mV). Miniture endplate potentials, endplate potentials, action potentials, the current‐voltage relationship, and the resting intracellular Ca2+ concentration of the resealed fiber segments were similar to those in fibers that were intact from tendon to tenon. In addition, specific properties of intact fibers obtained from patients with various neuromuscular diseases were preserved in the resealed fiber segments prepared from the same patients or patients with the same diseases. These segments are easily obtained as a routine muscle biopsy performed under local anesthesia; they provide valuable preparations for the study of the pathophysiology of human skeletal muscle as well as for in vitro pharmacological tests.
Carpal tunnel area as a risk factor for carpal tunnel syndrome
Authors: Winn Francis J. , Habes Daniel J. 
Published: January 2005

AbstractCarpal tunnel area was investigated as a risk factor for carpal tunnel syndrome (CTS). It was hypothesized that if canal area is a risk fctor for the syndrome, individuals who develop the syndrome should have smaller carpal canal areas than those who remain free of the syndrome. Sixty‐one subjects, approximately equally divided by sex, age group, and diagnosis, were examined. A measurement of cross‐sectional areas of the carpal canal by computerized axial tomography indicated that individualsdiagnosed as carpal tunnel patients had significantly larger carpal canal areas than controls. The results indicate that a small carpal canal aresa does not appear to be a risk factor for carpal tunnel syndrome.
A myasthenia gravis plasma immunoglobulin reduces miniature endplate potentials at human endplates in vitro
Authors: Burges Judith , Wray Dennis W. , Pizzighella Sergio , Hall Zach , Vincent Angela 
Published: January 2005

AbstractA particular myasthenia gravis (MG) plasma Ig has previously been shown to block a single α‐bungarotoxin (α‐BuTX) binding site on embryonic rat muscle acetylcholine receptor (AChR). We have investigated its effect on embryonic/denervated and adult human AChR both in extracts and in situ. Plasma Ig blocked 125I‐α‐BuTx binding by greater than 85% to the AChR extracted from denervated muscle, but only by 55% to AChR extracted from normal human muscle. Incubation of intact human muscle fibers with the plasma Ig reduced 125I‐α‐BuTx binding to the endplate AChRs by 63%, and substantially decreased the amplitude of miniature endplate potentials. We conclude that anti‐α‐BuTx site antibodies, when present, can be important in the pathophysiology of the disease.
Carpal tunnel syndrome : Which finger should be tested? An analysis of sensory conduction in digital branches of the median nerve
Authors: MacDonell Richard A. L. , Schwartz Martin S. , Swash Michael 
Published: January 2005

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 used.
Neuralgic amyotrophy with involvement of cranial nerves IX, X, XI and XII
Authors: Pierre Philippe A. , Laterre Christian E. , Van Den Bergh Peter Y. 
Published: January 2005

AbstractWe report a patient who presented with involvement of multiple cranial nerves associated with otherwise typical neuralgic amyotrophy. This syndrome of unknown etiology is not limited to the brachial plexus. Simultaneous involvement of cranial nerves IX, X, XI, and XII is a unique presentation. The electrophysiological data indicate the presence of a multifocal neuropathy.
Myasthenia gravis presenting as weakness after magnesium administration
Authors: Bashuk Robert G. , Krendel David A. 
Published: January 2005

AbstractWe studied a patient with no prior history of neuromuscular disease who became virtually quadriplegic after parenteral magnesium administration for preeclampsia. The serum magnesium concentration was 3.0 mEq/L, which is usually well tolerated. The magnesium was stopped and she recovered over a few days. While she was weak, 2‐Hz repetitive stimulation revealed a decrement without significant facilitation at rapid rates or after exercise, suggesting postsynaptic neuromuscular blockade. After her strength returned, repetitive stimuation was normal, but single fiber EMG revealed increased jitter and blocking. Her acetylcholine receptor antibody level was markedly elevated. Although paralysis after magnesium administration has been described in patients with known myasthenia gravis, it has not previously been reported to be the initial or only manifestation of the disease. Patients who are unusually sensitive to the neuromuscular effects of magnesium should be suspected of having an underlying disorder of neuromuscular transmission.
Quantitative clinical electrophysiology in the evaluation of nerve injury and regeneration
Authors: Dorfman Leslie J. 
Published: January 2005

AbstractNeuromuscular elecrophysiological techniques can provide clinically important information about the localization, severity, and pathophysiology of peripheral nerve injuries, and about the progress of reinnervation. The relevant variables for study are compound nerve and muscle action potentials, motor unit action potentials, and denervation potentials. Available methods do not permit meaningful quantitation of regeneration. Newer methods under development attempt to estimate the number of motor units in a muscle and the number of axons in a nerve.
Single fiber EMG evaluation in denervation and reinnervation
Authors: Wiechers David 
Published: January 2005

AbstractSFEMG can be used o follow the course of reinnervation. The parameters of fiber density, mean jitter and percent blocking must each be followed and related to the type of injury to determine the stage of reinnervation. The few reported cases in the literature of SFEMG recordings followed over time after nerve compromise are reviewed and an additional case is presented by the author. Mean jitter values can return to normal approximately 1½ years postonset of reinnervation. Some individual recordings may remain abnormal permanently.
Schwartz–Jampel syndrome with dominant inheritance
Authors: Pascuzzi Robert M. , Gratianne Roberto , Azzarelli Biagio , Kincaid John C. 
Published: January 2005

AbstractThe Schwartz–Jampel syndrome (SJS) is a rare congenital multisystem disorder of unknown pathogenesis which is characterized by distinct faces, skeletal deformities, joint contractures, short stature, muscle hypertrophy, clinical myotonia, and continuous muscle fiber activity. The inheritance pattern of SJS has been assumed to be autosomal recessive. We report the occurrence of the classic SJS syndrome in both a father and son in a non‐consanguineous family, suggesting that SJS has the potential for a dominant pattern of inheritance.
Carpal tunnel syndrome: Correlations between pressure measurement and intraoperative electrophysiological nerve study
Authors: Luchetti Riccardo , Schoenhuber Rudolf , Alfarano Mauro , Deluca Stefano , De Cicco Giorgio , Landi Antonio 
Published: January 2005

AbstractIn 19 carpal tunnel syndrome (CTS) patients and 4 control subjects a catheter was introduced into the carpal tunnel and slowly retracted in 5 mm steps. Pressure was measured with the continuous infusion technique. In the same group of patients and controls, median nerve antidromic sensory action potential (aSAP) was detected introperatively stimulating proximally (S1), in the center (S2), and distally (S3) to the carpal tunnel and recording from the third finger (R). Sensory conduction velocity (SCV) and aSAP amplitude were considered in S1‐S2, S2‐S3 and S3‐R segments. The intracarpal tunnel pressure was significantly higher in CTS patients than in controls, with the highest values located between 25 and 35 mm distal to the proximal border of the flexor retinaculum. SCV and aSAP amplitude were also decreased most often in the distal part (S2‐S3) of the carpal tunnel.
On the shape of the normal turns‐amplitude cloud
Authors: Nandedkar Sanjeev D. , Sanders Donald B. , Stalberg Erik V. 
Published: January 2005

AbstractFactors that affect the shape of the so‐called “normal cloud” of the turns and amplitude measurements of the electromyographic interference pattern are investigated. As the force of voluntary contraction increase from low to moderate levels, the number of turns in the signal increase faster than does the mean amplitude change between turns. This results in a cloud that is concave downward. At higher force levels, the pattern is reversed. The overall shape of the cloud thus depends on the maximum effort at which recordings are made, which is determined by the procedure of muscle activation.
Nerve‐muscle involvement in a large family with mitochondrial cytopathy: Electrophysiological studies
Authors: Torgbergsen Torberg , Stålberg Erik , Bless Janne K. 
Published: January 2005

AbstractThirteen patients with mitochondrial cytopathy were investigated. They represent different generations, ages, stages, and severities of the disease. All were assumed to have the same metabolic defect. The disease is a multisystem disorder with a metabolic defect located at complex 1 in the respiratory chain. Clinically, the disorder gives symptoms such as hearing loss, retinal pigmental degeneration, ataxia, cardiomyopathy, muscular fatiguability and neuropathy. The patients were investigated with nerve conduction studies, concentric needle EMG, SFEMG, and macro EMG examinations. Neurophysiologic studies revealed signs of myopathy in both the younger members and in those with slight muscular symptoms. In the more advanced stages, neuropathic changes of the axonal type were seen as well. Macro EMG was interpreted as indicating muscle fiber membrane abnormalities in the early stages. Single fiber EMG studies indicate that this metabolic defect does not distrub neuromuscular transmission.
Expression of superfast myosin in aneural regenerates of cat jaw muscle
Authors: Bssc Joseph F. Y. Hoh , Hughes Suzanne 
Published: January 2005

AbstractWe investigated whether innervation is necessary for the expression of superfast myosin in regenerating cat jaw‐closing muscle. Strips of jaw muscle were permitted to regenerate bilaterally in the beds of a fast limb muscle with innervation on one side being prevented surgically. Immunocytochemical analyses using anti‐myosin heavy chain antibodies were done at various times postoperatively, the latest being after 78 days. We found little difference between innervated and uninnervated regenerates up to 27 days postoperatively. All regenerating myotubes expressed fetal myosin. In addition, some myotubes stained for superfast or slow myosin, while others stained for both superfast and slow myosins. Subsequently, uninnervated myotubes became atrophic but continued to express fetal, slow, and superfast myosins while innervated myofibers suppressed fetal and slow myosin expression. These results are consistent with the notion that satellite cells of jaw‐closing muscles are committed to express superfast myosin during myogenesis, and that the expression of this program is independent of innervation.
External recording of twitch time course in cat ankle muscles
Authors: Eerbeek O. , Kernell D. 
Published: January 2005

AbstractIn chronic experiments concerning the activity‐dependent plasticity of muscle properties, a simple and noninvasive method was used for monitoring changes of twitch speed in conscious adult cats. The animals had been provided with implanted electrodes for nerve stimulation, and a hand‐held force transducer was pressed against the fully extended ankle joint while single test pulses were delivered to the common peroneal nerve. In the present report, this technique for the recording of ankle twitches is subjected to critical analysis and evaluation. The measurements were highly reproducible with respect to contraction time (time‐to‐peak) but less so for half‐relaxation time and twitch amplitude; other methods should be used for the long‐term monitoring of contractile force. The total force (torque) of the ankle twitch was mainly produced by tibialis anterior (about 45%), peroneus longus (PerL; 27%) and extensor digitorum longus (23%). The ankle twitch produced by PerL alone had about the same contraction time as that of all the muscles together. Among muscles that had become changed as a result of long‐term electrical stimulation there was, in general, a good correspondence between the contraction times from simple external recordings of ankle twitches and those separately measured for PerL under general anesthesia (force transducer then directly connected to PerL tendon).
Assessment of locomotor function in young boys with duchenne muscular dystrophy
Authors: Smith Robert A. , Newcombe Robert G. , Sibert Jo R. , Harper Peter S. 
Published: January 2005

AbstractThirty‐three young boys (mean age 3.42 years) with Duchenne muscular dystrophy (DMD) and 21 normal control boys (mean age 3.51 years) were studied prospectively to determine whether it is possible to objectively assess locomotor function in young boys with DMD so that they can be included in treatment trials. An initial reproducibility study using a hand‐held myometer demonstrated that this method was not useful. The Hammersmith Motor Ability Score demonstrated an increase in developmental abilities with age which was markedly different from normal. The locomotor quotient of the Griffiths' Scales demonstrated a deterioration of quotient scores and is a useful method of assessment that could be used in treatment trials involving young boys with DMD. Sample size planning for treatment trials is discussed.
A technique for needle localization in paraspinal muscles with cadaveric confirmation
Authors: Haig Andrew J. , Moffroid Mary , Henry Sharon , Haugh Larry , Pope Malcolm 
Published: January 2005

AbstractInvasive electromyography (EMG) of the paraspinal muscles is useful in clinical and research settings. No technique for localization of the needle in specific fascicles has been validated. Recent descriptions of the segmented innervation of the multifidus imply that such a technique would add greatly to the EMG determination of root level of a radiculopathy. We have developed a technique for localization which relies on palpation of bony structures and needle insertion at certain angles and depths. The technique was evaluated by injecting latex dye in 199 locations in 13 cadavers. Dissection demonstrated that the technique was accurate in 91 of 112 injections into specific fascicles of the multifidus (originating from different spinous processes), 39 of 43 injections into the longissimus, and 35 of 44 injections into the iliocostalis. Certain types of errors would not have occurred with the aid of EMG in vivo. When these are added to the correct injections, accuracy improves 97%, 93%, and 82%, respectively. The technique described here should be useful for kinesiological studies, biopsies and injections, as well as for the EMG confirmation of a radiculopathy.
Comparison of stimulation and insulin effects on denervated mouse soleus muscles
Authors: Hofmann William W. 
Published: January 2005

AbstractA comparison has been made between the responses of denervated mouse soleus muscles to direct electrical stimulation, as reported by earlier workers, and to incubation with supraphysiological concentrations of insulin. The parameters of interest were resting membrane potential (RMP), qualities of the active state, the amount of alpha bungarotoxin (BUTX) binding, and chemosensitivity, as measured by the strength of acetylcholine (ACh)‐induced contractures. In all aspects, the changes recorded after insulin, were in the same direction as with direct stimulation, however, owing to the time limitations of in vitro testing were smaller. It is suggested that the effects of electric shocks on denervated muscles are the result of activation of the insulin receptor, or some similar macromolecule, which appears to be sensitive to the membrane potential. The possible interrelations between acetylcholine and insulin receptors in neurotrophic control are discussed.
Glucocorticoids and immunosup pressants do not change the prevalence of necrosis and regeneration in mdx skeletal muscles
Authors: Weller Boaz , Massa Roberto , Karpati George , Carpenter Stirling 
Published: January 2005

AbstractTherapeutic doses of methylprednisolone, azathioprine, cyclosporin A, and cyclophosphamide administered to mdx mice between 15 and 45 days of age failed to significantly influence the time course and prevalence of necrosis and regeneration or serum creatine kinase activity. This finding contrasts with previously reported findings of beneficial effects of glucocorticoids in Duchenne muscular dystrophy (DMD). This may indicate that, mechanisms upon which beneficial effects of glucocorticoids depend in DMD, do not operate (sufficiently) in mdx mice.
Dorsal nerve of the penis nerve conduction velocity: A new technique
Authors: Clawson David R. , Cardenas Diana D. 
Published: January 2005

AbstractIn the evaluation of a possible peripheral neuropathic process as the etiology of erectile dysfunction, studies of the dorsal nerve of the penis may be unique in that they allow examination of the most distal segment of pudendal nerve in isolation. This study describes a new technique using a simple traction device for elongation of the penis to determine the orthodromic nerve conduction of the dorsal nerve of the penis. With stimulation at the glans, and recording at the base of the penis, the value obtained in 20 normal subjects was 36.2 ± 3.2 m/s with an amplitude of 2.29 ± 1.08 mV.