bluuebunny/crossref_metadata_2025_split huggingface dataset:
Technical artifact simulating “Motor Axonopathy”
Authors: Gilchrist James M. , Dosremedios Edmund , Johnson Gary , Tornabene Joseph 
Published: January 2005

AbstractWe describe 3 patients, referred for other problems, whose nerve conduction studies revealed low compound motor amplitudes, normal motor conduction velocities and normal sensory nerve studies, consistent with a motor axonopathy. EMG was normal. The unexpected nature of these findings precipitated a search for technical artifact. A partial transection of the active electrode was found. After replacement, repetition of the motor studies was normal. Our explanation was of a normal “reference” signal being subtracted from a present but diminished “active” signal.
Cyclosporin a therapy in paraprotein‐associated neuropathy
Authors: Waterston John A. , Brown Martin M. , Ingram David A. , Swash Michael 
Published: January 2005

AbstractA case of IgG paraprotein‐associated demyelinating neuropathy complicated by respiratory failure, which was unresponsive to standard immunosuppressive drug therapy, is reported. Cyclosporin A therapy resulted in a marked clinical recovery with objective improvement in nerve conduction and vital capacity. The beneficial response suggests that cell‐mediated immunity is an important pathogenetic mechanism, and that cyclosporin A may be useful in the treatment of other refractory cases of paraprotein‐associated neuropathy.
Fatal familial infantile glycogen storage disease: Multisystem phosphofructokinase deficiency
Authors: Amit Rami , Bashan Nava , Abarbanel Jacob M. , Shapira Yehuda , Sofer Shaul , Moses Shimon 
Published: January 2005

AbstractAn infant girl of consanguinous Bedouin parents suffered from fatal early onset of progressive generalized muscle weakness. Her older brother suffered from similar weakness and cardiomyopathy, which led to his death at the age of 21 months. A muscle biopsy performed on the propositus at the age of 9 months was PAS‐negative, and showed nonspecific myopathic changes. A second muscle biopsy, performed at 21 months of age, a few days before her death, and postmortem study of heart and liver, disclosed excessive extralysosomal glycogen storage and reduced phosphofructokinase‐1 (PFK‐1) activity. Because the genes encoded for PFK‐1 in liver and muscle are located on separate chromosomes, the reduced enzyme activity in both tissues could not be related to a single mutation for this enzyme. Activity of 6‐phosphofructose‐2‐kinase (PFK‐2), a recently discovered physiological activator to all PFK‐1 isozymes, was normal in the liver. The possibility that this multisystem PFK‐1 deficiency may be related to the absence of a yet unknown activator, common to all PFK‐1 isozymes, is discussed.
AAEM minimonograph #38: Neuropathies in connective tissue disease
Authors: Olney Richard K. 
Published: January 2005

AbstractNeuropathies are common in patients with known or suspected connective tissue disease. A vasculitic mononeuropathy multiplex is often seen in patients initially presenting with polyarteritis nodosa or developing arteritis as a complication of rheumatoid arthritis. However, vasulitic neuropathy may become confluent and present as as distal symmetrical polyneuropathy or occur without systemic necrotizing vasculitis. Distal symmetrical polyneuropathies without associated vasculitis are also common in many connective tissue diseases. Compression neuropathies, especially carpal tunnel syndrome, occur with increased frequency in rheumatoid arthritis. Finally, certain neurpathies may be the major presenting feature of particular connective tissue diseases. For example, trigeminal neuropathy often heralds the onset of systemic sclerosis or mixed connective tissue disease, and sensory neuronopathy may be the initial presenting feature of Sjögren's syndrome.
The heart in becker muscular dystrophy, facioscapulohumeral dystrophy, and bethlem myopathy
Authors: de Visser Marianne , de Voogt Willem G. , la Rivière Guusje V. 
Published: January 2005

AbstractWe report a study, assessing involvement of the heart in 33 familial cases of Becker muscular dystrophy (BMD), 31 familiar cases of facioscapulohumeral (FSH) dystrophy, and 27 familial cases of Bethlem myopathy. In the patients with BMD, correlations of myocardial involvement with age and extent of musculoskeletal involvement were made. We performed physical examination, chest X‐ray, electrocardiographic (EKG), and echocardiographic extients with FSH dystrophy. Thirteen patients with BMD (45%) showed EKG changes similar to those found in Duchenne muscular dystrophy. Only 1 of the 13 individuals with cardiac invovement was wheelchairbound. We found no evidence of cardiac changes in the patients with FSH dystrophy. In Bethlem myopathy, only 1 patient had a form of hypertrophic cardiomyopathy (asymmetrical septal hypertrophy).
Leakage of carbonic anhydrase III from normal and denervated rat skeletal muscle following contractile activity
Authors: Ashmark Håkan , Wistrand Per J. 
Published: January 2005

AbstractSkeletal muscle extracellular carbonic anhydrase III was investigated in anesthetized rats by a microdialysis technique. A small dialysis probe was inserted into the tibialis anterior (TA) muscle and perfused continuously. Perfusates were collected before and during muscle contraction, induced by electrical stimulation of the muscle or of the sciatic nerve. In the perfusate of resting normal and denervated muscle, the concentration of CA III was 10 to 12 ng/mL, as measured by a radiommunosorbent technique. During contractile acitvity, the concentrations of CA III increased markedly in hte normal and denervated muscle. A TA muscle suspended in physiological saline behaved similarly, even though the leakage before and during contrafction was higher than in vivo. The results show that skeletal muscle leaks CA III both in vivo and in vitro, a leakage which was markedly increased by contractile activity. The microdialysis technique should also be useful in humans to study the efflux of various proteins from different kinds of diseased or fatigued muscles.
Reciprocal changes in myosin isoform mRNAs of rabit skeletal muscle in response to the initiation and cessation of chronic electrical stimulation
Authors: Brownson Carol , Little Pauline , Jarvis Jonathan C. , Salmons Stanley 
Published: January 2005

AbstractChanges in myosin heavy chain (MHC) mRNAs were studied in rabbit fasttwitch muscles during continuous electrical stimulation at 10 Hz for periods up to 3 weeks, and during the first 12 days of the recovery process that followed cessation of 6 weeks' stimulation. Two cDNA probes were used to detect MHC mRNAs specific to fast‐ and slow‐twitch skeletal muscle in RNase protection assays and Northern‐ and slot‐blot analyses. The isolation and base sequence of one of these probes, corresponding to the MHC gene expressed in soleus (slow‐twitch), is described. At an early stage of the response to stimulation, fast MHC mRNA was replaced by slow MHC mRNA. During recovery, this process occurred in reverse but took longer. The time course of recovery was slightly faster in tibialis anterior than in extensor digitorum longus. The changes in mRNAs during both stimulation and recovery reflected changes in the corresponding muscle proteins.
Transcranial magnetic stimulation of the facial nerve: Intraoperative study on the effect of stimulus parameters on the excitation site in man
Authors: Schmid Urs D. , Møller Aage R. , Schmid Judith 
Published: January 2005

AbstractMagnetic stimulation (magStim) of the intracranial facial nerve is performed in clinical and research settings, but the activation site is a matter of controversy. Latencies of nasalis muscle responses to magStim were, therefore, compared with those obtained by direct electrical stimulation of the facial nerve (a) at the root exit zone (REZ); (b) at the porus of the facial canal; and (c) in the stylomastoid fossa during microvascular decompression operations in the cerebellopontine angle (CPA). Measurements of latencies of the nasalis muscle response, obtained while the stimulating coil was placed over the parieto‐occipital area of the scalp, indicated that it was the labryinthine segment of the facial canal, 5 to 16 mm distal to the CPA, that was activated. This would be in agreement with studies of physical models reported in the literature that showed (a) the strength of the electrical current generated by a magnetic field is particularly high close to a nerve foramen; and (b) excitation to magStim is most likely to occur where the induced electrical field changes rapidly over distance, i.e., at anatomical boundaries between media of high and low specific resistance. These characteristics are found at the end of the labyrinthine segment of the facial canal, where the facial nerve leaves the low‐resistance cerebrospinal fluid and enters the high‐resistance petrous bone. The site of neural excitation is robust and unaffected by stimulus intensity and current direction within a wide range, or by large changes in location of the coil. The practical implication of this study is that transcranial magStim does not reflect nerve conduction in segments of the facial nerve that are located proximal to the facial canal, which accounts for about 40% of the nerve length between the REZ and the stylomastoid fossa.
Twitch and tetanus in mdx mouse muscle
Authors: Quinlan John G. , Johnson Scott R. , McKee Mari K. , Lyden Sean P. 
Published: January 2005

AbstractWe compared mdx and C57BL10 anterior tibial muscle force in situ (single pulse, multiple pulse, staircase, posttetanic potentiation, and fatiguing stimulation patterns) to define muscle strength, physiology, and fatigue resistance. The relatively hypertrophied mdx muscle showed: reduced strength (N/cm2), an increased twitch‐tetanus ratio, and resistance to postfatigue twitch slowing. These differences implicate altered mdx calcium regulation, and emphasize the importance of measuring both muscle function and morphology in mdx treatment trials. © 1992 John Wiley & Sons, Inc.
Effects of phenytoin in two myotonic horses with hyperkalemic periodic paralysis
Authors: Beech Jill , Fletcher Jeffrey E. , Tripolitis Linda , Lindborg Sue 
Published: January 2005

AbstractThe effects of phenytoin treatment were evaluated in 2 myotonic horses with hyperkalemic periodic paralysis (HPP). Phenytoin treatment abolished the clinical signs of muscle fasciculations following oral potassium challenge and decreased or abolished repetitive firing and myotonic discharges found on electromyographic examination. In both horses, an abnormally low threshold for calcium‐induced calcium release was measured in heavy sarcoplasmic reticulum fractions from skeletal muscle, and this threshold increased with phenytoin treatment. Results suggest phenytoin is useful in modifying disordered ion regulation in the sarcolemma and sarcoplasmic reticulum of skeletal muscle in equine hyperkalemic periodic paralysis. © 1992 John Wiley & Sons, Inc.
The spectrum of concentric macro EMG correlations. Part I. Normal subjects
Authors: Bauermeister Wolfgang , Jabre Joe F. 
Published: January 2005

AbstractUsing a concentric macro electrode, both the concentric and macro action potentials of a motor unit were analyzed for duration, area, and amplitude. Eighty‐six different motor units were analyzed from the tibialis anterior muscle in 10 normal subjects. The aim of this work was to compare concentric and macro action potential measurements of the same motor unit. The study revealed significant correlations between concentric and macro samples, with the concentric potential's area correlating better with the macro potential than its amplitude. This shows that the 10 to 15 muscle fibers studied by the concentric electrode serve as a good sample of the motor unit as a whole. We briefly review the technique used in concentric macro EMG, as well as describe the methods used for collecting and comparing both concentric and macro action potentials. © 1992 John Wiley & Sons, Inc.
Inorganic mercury is transported from muscular nerve terminals to spinal and brainstem motoneurons
Authors: Arvidson Björn 
Published: January 2005

AbstractThe distribution of mercury within the brainstem and spinal cord of mice was investigated with the autometallographic technique after intramuscular administration of a single dose of mercuric mercury (HgCl2). Deposits of mercury were localized to motor neurons of the spinal cord and to to brainstem motor nuclei; i.e., neurons with their peripheral projections outside the blood‐brain barrier. Unilateral ligation of the hypoglossal nerve prior to the injection of HgCl2 prevented the accumulation of mercury deposits in the ipsilateral hypoglossal nucleus. The selective accumulation of mercury in spinal and brainstem motoneurons is most probably due to a leakage of metal‐protein complexes form capillaries in muscle into myoneural junctions, followed by uptake into nerve terminals and retrograde axonal transport. The possible link between this process and the developmentof motor neuron degeneration in ALS is discussed. © 1992 John Wiley & Sons, Inc.
An augmented computer model of motor unit reorganization in neurogenic diseases of skeletal muscle
Authors: Lester James M. , Soule Norman W. , Bradley Walter G. , Brenner John F. 
Published: January 2005

AbstractA computer model of denervation and complete reinnervation in skeletal muscle was originally developed for the purpose of furthering an understanding of the underlying mechanisms of motor unit reorganization in neurogenic diseases. We now describe its successor, a computer model for investigating different rates of denervation and reinnervation, as well as incomplete reinnervation. The new model introduces the concept of permanent denervation and features enhanced interactive control over the distribution of motor unit centers and additional measures of dispersion and co‐dispersion of muscle fibers. The use of this model for investigating pathophysiologically significant issues in denervating diseases is illustrated pathophysiologically significant issues in denervating diseases is illustrated with five different sets of parameters. These simulate some of the processes that may be operational in chronic spinal muscular atrophy, amyotrophic lateral sclerosis, and progressive postpolio muscular dystrophy. The enhanced model will allow in‐depth analysis of the influence of hypothesized pathophysiological processes on clinical, electrophysiological and pathological outcomes in human disease. © 1993 John Wiley & Sons, Inc.
Single fiber EMG in a congenital myasthenic syndrome associated with facial malformations
Authors: Sadeh Menachem , Blatt Ilan , Goldhammer Yochanan 
Published: January 2005

AbstractSix patients with a newly described genetic syndrome in Iraqi and Iranian Jews of congenital myasthenia associated with facial malformations were studied with voluntary and stimulation single fiber EMG (SFEMG). Voluntary SFEMG revealed abnormal jitter in all patients in both extensor digitorum communis (EDC) and orbicularis oculi (OOC) muscles, though much smaller in the clinically unaffected EDC. SFEMG study of OOC muscle by axonal stimulation at rates from 1 to 48 Hz showed the most increased jitter at the highest stimulation frequencies in the majority of end‐plates, one‐third of which showed maximal jitter at intermediate rates. These results may suggest a postsynaptic abnormality as the underlying cause for the neuromuscular transmission defect, and demonstrate the usefulness of SFEMG in the diagnosis of congenital myasthenia. © 1993 John Wiley & Sons, Inc.
Factors affecting muscle fiber transformation in cross. Reinnervated muscle
Authors: Thomas P. E. , Rantunga K. W. 
Published: January 2005

AbstractNerves of two fast muscles [peroneus longus (PL) and extensor digitorum longus (EDL)], having different type 2 muscle fiber compositions, were used to cross‐reinnervate the slow soleus muscle in the rat. Contraction characteristics, histochemical muscle fiber type compsotions and myosin heavy chain (MHC) isoform compositions were determined for the reinnervated muscles. Shortening velocity increased in soleus muscles crossreinnervated with EDL nerve [X‐SOL(EDL)] but not in muscles cross‐reinnervated with PL nerve [X‐SOL(PL)]. Type 2A MHC isoform content was increased in X‐SOL(EDL) but not in X‐SOL(PL), where MHC isoform composition remained similar to normal soleus. The complement of type 1 (slow) muscle fibers was reduced and that of type 2 (fast) fibers increased in both types of X‐SOL muscle, but this change was significantly greater in X‐SOL(EDL); the majority of the type 2 fibers in X‐SOL muscles were of type 2A. Results show that “the type 2 composition” of the reinnervating motoneuron pool is an important factor in determining the transformation of a target slow muscle after cross‐reinnervation. © 1993 John Wiley & Sons, Inc.
Muscle ultrasonography and computed tomography in elderly trained and untrained women
Authors: Sipilä Sarianna , Suominen Harri 
Published: January 2005

AbstractUltrasonography (US) and computed tomography (CT) were compared in studying the associations between long‐term physical training and quadriceps muscle mass and structure in female athletes and controls, aged 66–85 years. Muscle cross‐sectional area (CSA) measured using US correlated highly with that measured using CT, but the latter technique yielded 30% higher values on average. The echo intensity of the fasciae and bone measured by US correlated positively with the mean radiological density and negatively with the relative proportion of fat obtained from CT. Low intramuscular echo intensity was accompanied by high muscle density and low relative proportion of fat. The athletes had larger quadriceps CSA and more discerned fasciae and connective tissue septa but less fat than the controls. The results indicate that US and CT both are useful methods in comparing muscle mass and structure in elderly trained and untrained women. © 1993 John Wiley & Sons, Inc.
Metabolic changes in reflex sympathetic dystrophy: A 31P NMR spectroscopy study
Authors: Heerschap Arend , Hollander Jan A. Den , Reynen Han , Goris R. Jan A. 
Published: January 2005

AbstractThe lower leg skeletal muscles of 11 patients affected by reflex sympathetic dystrophy were investigated at rest by 31P nuclear magnetic resonance spectroscopy at a fieldstrength of 1.5 T. The results were compared with similar investigations of unaffected lower leg muscles of patients and volunteers. A significant increase was observed for the average tissue pH of the muscles of affected legs as deduced from the chemical shift of the resonance for inorganic phosphate. The average inorganic phosphate/phosphocreatine ratio of these muscles was also increased. The impairment of high energy phosphate metabolism, as deduced from the NMR data, may be caused by cellular hypoxia or diminished oxygen utilization, which would agree with previous findings that oxygen extraction is reduced in extremities affected by reflex sympathetic dystrophy. © 1993 John Wiley & Sons, Inc.
Multiple descending corticospinal volleys demonstrated by changes of the wrist flexor H‐reflex to magnetic motor cortex stimulation in intact human subjects
Authors: van der Linden Chris , Bruggeman Richard 
Published: January 2005

AbstractTo study noninvasively multiple descending volleys on alpha motoneurons, we used a 30–50% maximum H‐reflex in the wrist flexor muscle conditioned by a subthreshold magnetic stimulus of the contralateral motor cortex as a parameter of motoneuronal excitability in seven neurologically healthy subjects. The time interval of the median nerve (test) stimulus and the magnetic (conditioning) stimulus was varied. In all subjects the conditioned H‐reflex significantly (P < 0.05) enhanced at conditioning‐test intervals between ‐1 ms and +10 ms. Superimposed on the overall facilitation there were at least two short duration periods of enhanced facilitation in all but one subject. These periods were separated by 2–4 ms and suggest increased excitability at the alpha motoneuronal pool brought on by the descending volleys. We conclude that with subthreshold magnetic cortical stimuli it is possible to produce multiple descending corticospinal volleys, which probably represent descending I waves. This should be taken into account when analyzing motor evoked potentials (MEPs) in clinical studies. © 1993 John Wiley & Sons, Inc.
Comparison of sympathetic sudomotor and skin responses in alcoholic neuropathy
Authors: Navarro Xavier , Miralles Ramon , Espadaler Josep M. , Rubiés‐Prat Juan 
Published: January 2005

AbstractWe evaluated sympathetic sudomotor and parasympathetic vagal function in 30 chronic alcoholic patients and 28 control subjects by means of silicone imprints, sympathetic skin responses (SSR), and cardiorespiratory reflex tests. Mean values from alcoholic patients were significantly lower than those from control subjects for all tests. The number of secreting sweat glands (SGN) was below normal in the foot of 18 patients, and in the hand of 7 patients; 16 patients had absent SSR on the sole, and 4 on the palm. Only two patients had both test results abnormal on the hand and 10 on the foot. The SGN did not correlate with the amplitude of the SSR in the subjects studied. There was no clear correlation of abnormalities found in cardiorespiratory tests and sympathetic tests. Abnormalities in sensory nerve conduction were associated with absent SSR, but not with decreased SGN. The silicone mold technique is a more specific test to detect abnormalities in sympathetic efferent fibers, as SSR may be influenced by sensory afferent fiber involvement. © 1993 John Wiley & Sons, Inc.
Purification of human muscle satellite cells by flow cytometry
Authors: Baroffio Anne , Aubry Jean‐Pierre , Kaelin Andre , Krause Ryoko M. , Hamann Martine , Bader Charles R. 
Published: January 2005

AbstractTo purify satellite cells directly from human muscle biopsies, we have developed a method based on size separation of dissociated cells by flow cytometry. Immediately after tryptic dissociation of human muscle biopsies and elimination of erythrocytes, microscopic observation and flow cytometry analysis of cell suspensions revealed two populations of cells differing in size and nucleocytoplasmic ratio. Clonal cultures of these two cell types with a manual procedure demonstrated that only the small cells were myogenic satellite cells. Flow cytometry‐sorting and analysis of the small cell population showed that (1) all sorted cells contained desmin immediately after dissociation and plating; (2) more than 98% of the cells expressed the 5.1.H11 epitope after 2 weeks of proliferation in culture; and (3) 90% of the sorted cells were able to form myotubes when cultivated at low density or in clonal cultures. Thus, human muscle satellite cells can be directly purified from human muscle samples using flow cytometry. © 1993 John Wiley & Soncs, Inc.
The rigid spine syndrome: A vacuolar variant
Authors: Lotz Barend P. , Stübgen Joeerg‐P 
Published: January 2005

AbstractThe rigid spine syndrome encompasses a number of disorders. We report 7 males and 2 females with this phenotype and a single, not previously reported, nosology. The salient muscle histological features were autophagic vacuoles, vacuoles containing capillaries, muscle spindle swelling, and type l fiber predominance. Disease onset was before age 6 years in all patients. Inheritance was probably autosomal recessive as siblings were affected in two families. Pulmonary function tests showed severely restricted ventilation, 3 patients required nocturnal ventilatory assistance, 2 patients had cor pulmonale, and mitral valve abnormalities were common. Serum CK levels were moderately elevated. EMG studies showed evidence of an active, chronic myopathy. The mean motor unit potential duration was statistically significantly shorter compared to controls in the triceps and anterior tibial muscles. Single fiber EMG “jitter” and evoked potential studies were normal. © 1993 John Wiley & Soncs, Inc.