bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tellurium‐induced demyelination: An electrophysiological and morphological study
Authors: Uncini Antonino , England John D. , Rhee Edward K. , Duckett Serge W. , Sumner Austin J. 
Published: January 2005

AbstractTellurium (Te) is a naturally occurring element with many industrial uses. Microinjection of 0.3 μg of potassium tellurite [K(2)TeO(3)] into the endoneurial space of rat tibial nerve causes a rapidly progressing focal conduction block as measured by the disappearance of the evoked compound muscle action potential (CAMP) of the intrinsic foot muscles following stimulation proximal to the injection site. Conduction block was fully established within 6 hours and persisted for approximately 7 days, followed by the appearance of low amplitude, long latency, temporally dispersed potentials. The proximal CMAPs increased in amplitude and decreased in latency and temporal dispersion until normalization by 28 days after injection. The distal CMAP showed a minimal decline in amplitude. Morphological observations showed splitting of myelin, especially in the paranodal regions, followed by accumulation of myelin debris in Schwann cells and macrophages. Although the exact mechanism remains unknown, this in vivo model provides a unique opportunity to study the electrophysiological and morphological correlates of an acutely evolving demyelinative process.
Nonlinear force addition of newly recruited motor units in the cat hindlimb
Authors: Clamann H. Peter , Schelhorn Teresa B. 
Published: January 2005

AbstractThe present experiments were designed to examine the interaction of simulaltaneoously active motor units. Pairs of medial gastrocnemius (MG) or soleus (Sol) units were stimulated individually and then together with constant frequency trains of 5–40 pulses per second. Stimulating two units asynchronously produced a smoother contraction than synchronous stimulation, but rarely a force increase. This contrasts with similar experiments on whole muscle bundles. A force increase may require that adjacent muscle fibers be active. The combined force to two motor units exceeded the algebraic sum of their separate forces by 12% in MG and 5% in Sol on average. The force a unit could sustain after a second unit fell silent was greater than the force the unit produced alone (21% in MG and 8% in Sol).We conclude that motor units produce more force when interacting than alone. During derecruitment the units remaining active produce more force than when recruited.
Demyelination induced by intraneural injection of human antimyelin‐associated glycoprotein antibodies
Authors: Willison Hugh J. , Trapp Bruce D. , Bacher John D. , Dalakas Marinos C. , Griffin John W. , Quarles Richard H. 
Published: January 2005

AbstractIgM monoclonal antibodies present in the sera from some patients with peripheral neuropathy react with an antigenic carbohydrate determinant that is present on the myelin‐associated glycoprotein (MAG) and other peripheral nerve glycoproteins and glycolipids. It is generally believed that the neuropathy in these patients may be caused by antibody‐ mediated nerve damage. Intraneural injection of serum from patients with this disease produced an extensive inflammatory, macrophage‐mediated demyelination of feline peripheral nerve. This only occurred with very fresh sera which had been supplemented with additional complement. Injection of sera from normal subjects failed to produce any demyelination. These results are in accordance with a recent study by Hays et al.13 and contradict earlier negative reports of similar studies. It is important to note that the pathology observed in these experimental studies bears little resemblance to that seen in the human neuropathy, and caution must therefore be exercised when interpreting this data in relation to the pathogenic mechanisms that might operate in the human disease.
Transient Lambert‐Eaton myasthenic syndrome associated with systemic lupus erythematosus
Authors: Bromberg Mark B. , Albers James W. , McCune W. Joseph 
Published: January 2005

AbstractWe present a patient who developed the Lambert–Eaton myasthenic syndrome (LEMS) in association with systemic lupus erythematosus (SLE). Severe proximal weakness with electrodiagnostic evidence of LEMS developed over 2 days during an exacerbation of cutaneous manifestations (bullous pemphigoid) associated with SLE. Following an increase in the daily dose of prednisone, there was complete clinical restitution of strength within 2 weeks and a slower resolution of electrodiagnostic abnormalities over 6 months. Marked serologic abnormalities were present at the onset and showed improvement over 6–8 months. LEMS had been infrequently described in association with SLE. The immunologic features of both SLE and LEMS suggest a linkage between the two diseases in this patient. We hypothesize that increased antibodies associated with exacerbation of SLE cross reacted with the neuromuscular junction membrane to produce LEMS.
Central core disease: Ultrastructure of the sarcoplasmic reticulum and T‐tubules
Authors: Hayashi Kazuko , Miller Rodman G. , Brownell A. Keith W. 
Published: January 2005

AbstractThe modified Golgi staining method was used to study the sarcoplasmic reticulum (SR) and t‐ tubules of skeletal muscle in central core disease. Significant pathological changes were documented in both of these organelles in seven patients. Pathological changes were seen in both core and non‐core regions, with the abnormalities being greatest in the cores. In noncore regions, distortions in the normal anatomy were minor. In cores, there was much more significant distortion of the normal anatomy and also an increase in the amount of SR and number of t‐tubules.
AAEE case report #18: Ulnar neuropathy in the distal forearm
Authors: Campbell William W. 
Published: January 2005

AbstractA 66‐year‐old professional golf instructor developed pain, numbness, and weakness in an ulnar distribution, but the lesion could not be localized to either elbow or wrist by routine nerve conduction techniques. Stimulation along serial 1‐cm increments in the distal forearm disclosed a point of focal conduction block approximately 7 cm proximal to the ulnar styloid. At surgery, the flexor carpi ulnaris was enlarged, with muscle fibers extending all along the normally tendinous distal portion. A dense fibrovascular band coursed from the ulnar artery to the abnormal muscle, compressing the adjacent ulnar nerve. Intraoperative electroneurography precisely localized the area of conduction abnormality and helped identify the band as the compressing structure. Within 2 months following surgical decompression there was complete resolution of conduction block with excellent clinical recovery.
Org.2766 stimulates collateral sprouting in the soleus muscle of the rat following partial denervation
Authors: de Koning Paul , Verhaagen Joost , Sloot Willem , Jennekens Frans G. I. , Gispen Willem H. 
Published: January 2005

AbstractThe influence of melanocortins on the process of collateral sprouting has been investigated in rat soleus muscle. The soleus muscle was partially denervated by transecting and ligating the L5 mixed nerve. Collateral sprouting was assessed by means of isometric twitch tension measurements of soleus motor units that remained following L5 transection. The smaller the number of remaining soleus motor units, the larger the extent of collateral sprouting. Seven days following partial denervation, the index of sprouting (ratio between twitch tension of motor units in partly denervated muscles and in normal muscles) was significantly increased by treatment with the ACTH4–9 analog Org.2766 (1 μg/48 hours). This increase appeared to be present also 28 days following partial denervation. The electrophysiological results were confirmed by histological investigations. The results provide evidence that Org.2766 increases the motor neuron collateral sprouting capacity of peripheral nerve. Org.2766 did not induce muscle fiber hypertrophy.
SSEP and F‐wave studies in acute inflammatory demyelinating polyradiculoneuropathy
Authors: Gilmore Robin L. , Nelson Kevin R. 
Published: January 2005

AbstractSomatosensory evoked potentials (SSEPs) and F‐wave responses were compared after tibial (PTN) and median (MN) nerve stimulation in patients with acute inflammatory demyelinating polyradiculoneuropathy (AIDP). Nineteen patients were evaluated within 2 weeks of AIDP onset. Each had F‐wave and PTN‐SSEP studies; 18 had MN‐SSEP studies. Ten patients had absent or prolonged MN‐SSEP latencies, whereas 16 had abnormal MN F‐wave studies. Seventeen patients had an abnormal PTN‐SSEP while 12 had abnormal PTN F waves. Every patient with an abnormal MN‐SSEP also had an abnormal PTN‐SSEP. The most common PTN‐SSEP findings were an absent or prolonged latency of N8 or N22. All patients had either an abnormal MN F wave or PTN‐SSEP.
Regeneration of skeletal muscle fibers from autologous satellite cells multiplied in vitro. An experimental model for testing cultured cell myogenicity
Authors: Alameddine Hala S. , Dehaupas Michèle , Fardeau Michel 
Published: January 2005

AbstractAn experimental model used to test in vivo myogenicity of autologous satellite cells multiplied in vitro is described. Free muscle autotransplantation served as the basis and was combined with x‐irradiation. Administration of 1500, 2500, and 3500 rad doses 24 hours before or after ischemia showed that inhibition of spontaneous regeneration is dose dependent and more efficient when irradiation was applied before injury. A single dose of 2500 rad before injury resulted in the formation of a cystic structure ideal for cell implantation. FITC‐latex beads and/or carbocyanine dyes were internalized by mononucleated satellite cells in vitro. Labeling did not affect survival or development of these cells. No sign of marker release or spreading from labeled to unlabeled cells was detectable unless by the fusion process. These labels were retained for several weeks. Grafting of labeled dense cellular suspensions into x‐irradiated ischemic muscles indicated that satellite cells retain their myogenic characteristic and are able to reform fully differentiated muscle fibers.
Calf enlargement in hereditary motor and sensory neuropathy
Authors: de Visser Marianne , Hoogendijk Jessica E. , de Visser Bram W. Ongerboer , Verbeeten Bernhard J. 
Published: January 2005

AbstractSix members originating from two families with hereditary motor and sensory neuropathy (hypertrophic and neuronal types) were noted to have enlarged calf muscles. Muscle computed tomography revealed that muscle enlargement in the propositus of the family with the hypertrophic type of HMSN was due to an increase in muscle and/or connective tissue. Computed tomography of the legs of the propositus of the family with the neuronal type of HMSN showed infiltration of the medial head of the gastrocnemius muscle by adipose tissue.
Dystrophin is localized to the plasma membrane of human skeletal muscle fibers by electron‐microscopic cytochemical study
Authors: Carpenter Stirling , Karpati George , Zubrzycka‐Gaarn Elizabeth , Bulman Dennis E. , Ray Peter N. , Worton Ronald G. 
Published: January 2005

AbstractElectron‐microscopic immunoperoxidase technique revealed plasmalemmal localization of dystrophin in microscopically normal human skeletal muscle fibers obtained from nine routine diagnostic muscle biopsies. There was no evidence of periodicity of the immunoreactive product nor was there any evidence of immunostaining in any organelle besides the plasma membrane. Dystrophin appears to be a cytoskeletal protein associated with the plasmalemma. Its function is presumed to be the maintenance of the mechanical stability of the surface membrane so that it can withstand the normal contraction‐induced stresses without disruption.
The refractory period of transmission in patients with carpal tunnel syndrome
Authors: Gilliatt Roger W. , Meer Jacob 
Published: January 2005

AbstractIn patients with the carpal tunnel syndrome (CTS) and in control subjects, pairs of shocks at intervals of 0.8 msec and 1.0 msec were used to stimulate the median nerve just above the wrist. Nerve action potentials were recorded at the elbow and from the index or middle finger. In patients but not in controls, recordings from the finger frequently showed loss of the second action potential of the pair, although a second action potential was present at the elbow. In these cases it seemed likely that impulse transmission through the carpal tunnel had failed because the damaged nerve at the level of the lesion had an increased refractory period of transmission (RPT) compared with its refractory period under the stimulating cathode. The possible diagnostic use of RPT measurement in CTS patients is discussed.
Diagnostic and prognostic value of electrophysiologic tests in meralgia paresthetica
Authors: Lagueny Alain , Deliac Marie M. , Deliac Philippe , Durandeau Alain 
Published: January 2005

AbstractElectrophysiologic diagnosis of unilateral meralgia paresthetica is usually assessed by side‐to‐side comparison of SNAP amplitudes, SNCVs, and SEP latencies following stimulation of lateral femoral cutaneous nerves. To determine the relevance for diagnosis of these tests and side‐to‐side comparison, the results were compared in patients with unilateral meralgia paresthetica and normal subjects. The long‐term outcome was also considered, in order to determine whether electrophysiologic findings contribute to the prognosis. In our study, SNAP amplitude comparison was found to be more useful for diagnosis than SNCV and SEP latency comparisons. However the value of the SNAP amplitude on the affected side, just as the results of the other tests, was not found to be predictive of the outcome. Also the results of the tests depend on the methods used and on the nerve's route.
Effect of dantrolene in duchenne muscular dystrophy
Authors: Bertorini Tulio E. , Palmieri Genaro M. A. , Griffin Judy , Igarashi Masanori , Hinton Abbie , Karas James G. 
Published: January 2005

AbstractWe have demonstrated that maneuvers capable of reducing Ca influx into cells have beneficial effects in dystrophic hamsters and Duchenne muscular dystrophy. Since dantrolene inhibits Ca release from the sarcoplasmic reticulum, its effects on DMD was studied in 7 patients of 6 to 13 years of age (mean 10.8 years). Patients were studied for 4 years with tri‐monthly evaluations of manual muscle testing (MMT), functional activity, and serum CK and aldolase. During the first 2‐year period, no medicines were given and served as control. In the second 2‐year period, dantfblene 8 mg/kg/d was administered. No side effects were observed. In 1 patient, mild, weakness occurred that disappeared when the dose was reduced to 6 mg/kg/d. The 95% confidence limit for the difference in slopes of regression lines from tri‐monthly MMT was asymmetric in favor of dantrolerte in 5 of 7 patients. Serum CK did not differ between the first and second year of the control and treatment periods, respectively. However, it fell significantly from the second year of control to the first year of treatment (P = 0.003). The fall during the first year of treatment was significantly greater (P <0.01) than in age‐matched natural history controls during the same length of observation. There was a 3‐fold reduction in CK when the pooled values of the first and second year control vs. treatment periods were analyzed. No changes were observed in functional activity and serum aidolase. The data suggest that dantrolene reduces serum CK in DMD associated with a lessening trend in MMT deterioration.
Involvement of thin afferents in carpal tunnel syndrome: Evaluated quantitatively by argon laser stimulation
Authors: Arendt‐Nielsen Lars , Gregersen Hans , Toft Egon , Bjerring Peter 
Published: January 2005

AbstractThe thin afferent nerves were tested quantitatively by determining the thresholds of warmth and pricking pain to argon laser stimulation and by measuring the brain potentials related to pricking pain. In 27 patients with electrophysiologically verified carpal tunnel syndrome these parameters were measured from fingers 3 and 5 on both hands. All patients had had sensory symptoms ranging from 3 months to 25 years. Both the thresholds were elevated (P <0.05) at finger 3 compared to measurements from finger 5, and compared to finger 3 in a group of 39 controls. Four patients with symptoms for more than 7 years had thresholds below the control values. The power of the pain‐evoked brain potentials elicited from finger 3 was lower (P <0.05) compared to finger 5, and compared to the control group (P <0.01). No correlations were found between the measured parameters and the clinical electrophysiological investigation. The findings support previous assumptions that chronic low‐force compressions cause impairment of intraneural microcirculation, and hence can affect the function of the thin afferents.
Nerve conduction studies in experimental non‐freezing cold injury: I. Local nerve cooling
Authors: Kennett Robin P. , Gilliatt Roger W. 
Published: January 2005

AbstractIn rabbits, the tibial nerve was exposed in the lower thigh under general anesthesia and cooled in a metal trough at 1 to 2°C or 5°C for 2, 3, or 4 hours. Nerve conduction studies showed local failure of conduction at the site of cooling which persisted after rewarming, and which was followed by distal degeneration of affected fibers. No persistent conduction block was seen. Changes in maximal velocity indicated that the fastest‐conducting motor and afferent axons had been preferentially affected. Histological finding in nerves examined at different intervals after cooling confirmed the physiological evidence of primary axonal damage, affecting particularly large diameter fibers. Paranodal demyelination was inconspicuous and restricted to regions just proximal to sites of axonal degeneration. No segmental demyelination was seen. These results clarify previous uncertainties as to the time‐course and distribution of nerve damage after local cooling at temperatures just above freezing point.
Variations in anatomy of the ulnar nerve at the cubital tunnel: Pitfalls in the diagnosis of ulnar neuropathy at the elbow
Authors: Campbell W. W. , Pridgeon R. M. , Riaz G. , Astruc J. , Sahni K. S. 
Published: January 2005

AbstractTwo processes account for most instances of ulnar neuropathy at the elbow: compression in the retroepicondylar groove, and compression by the humeroulnar aponeurotic arcade joining the two heads of the flexor carpi ulnaris. While conventional electrodiagnostic criteria may localize an ulnar neuropathy to the elbow, separating retroepicondylar compression from humeroulnar arcade compression is more difficult. In 130 cadaver elbows, we examined the relationships between the medial epicondyle, flexor carpi ulnaris, and ulnar nerve. The humeroulnar arcade lay from 3 to 20 mm distal to the medial epicondyle, the intramuscular course of the nerve through the flexor carpi ulnaris ranged from 18 to 70 mm, and the nerve exited the flexor carpi ulnaris 28 to 69 mm distal to the medial epicondyle. In 6 specimens, dense fibrous bands bridged directly between the medial epicondyle and the olecranon proximal to the cubital tunnel proper; accessory epitrochleoanconeus muscles were present in 14 specimens: both may cause ulnar neuropathy at the elbow. Anatomical variations may contribute to the difficulty in separating causes of ulnar neuropathy at the elbow.
Analysis of the organophosphate‐induced electromyographic response to repetitive nerve stimulation: Paradoxical response to edrophonium and D‐Tubocurarine
Authors: Maselli Ricardo A. , Soliven Betty C. 
Published: January 2005

AbstractWe studied the mechanism underlying acute organophosphate intoxication (OPI) through in‐vivo and in‐vitro electrophysiologic studies in rats injected with diisopropylfluorophosphate. Intoxicated rats showed weakness, repetitive compound muscle action potentials (CMAPs) in response to a single stimulus, and decremental response to repetitive nerve stimulation that was most pronounced at the second CMAP. The decrement was worsened with the administration of edrophonium, and was completely reversed by D‐tubocurarine. In‐vitro microelectrode studies showed no reduction in the amplitude of miniature endplate potentials (MEPPs) or in the quantal content of end‐plate potentials (EPPs). However, the half‐decay times of MEPPs and EPPs were significantly prolonged. Trains of stimuli induced sustained endplate depolarization via a “staircase phenomenon” of summation of prolonged EPPs, which was enhanced by edrophonium and abolished by D‐tubocurarine. These results indicate that sustained end‐plate depolarization can directly account for the decrement and weakness in acute OPI.
Scanning electron microscopic study of denervated and reinnervated intrafusal muscle fibers in rats
Authors: Dieler Ralf , Volker Anje , Schroder J. Michael 
Published: January 2005

AbstractIsolated muscle spindles from lower lumbrical muscles of rats were used to study the 3‐dimensional organization of intrafusal structures by scanning electron microscopy following (a) complete denervation, (b) reinnervation after a single crush lesion of the sciatic nerve, or (c) reinnervation after transection and immediate suture of this nerve. One week after complete denervation, previous sites of intrafusal motor endplates were transformed into sarcolemmal ovoid bulges. These bulges persisted in denervated muscle spindles up to 12 weeks. Regenerated motor nerve endings were detected on intrafusal muscle fibers 1 month, and thereafter following sciatic nerve crush injuries, and 3 months and later following transection and suture of the nerve. Furthermore, 3 different types of subsynaptic areas of motor nerve terminals were observed. The scanning electron microscopic technique also allowed visualization of splitting and fusion of intrafusal muscle fibers. The findings are discussed in view of their possible functional implications.
Reversible conduction block in human ischemic neuropathy after ergotamine abuse
Authors: Hömberg Volker , Reiners Karlheinz , Toyka Klaus V. 
Published: January 2005

AbstractConduction block [a significant reduction in compound muscle action potential (CMAP) amplitude after proximal compared to distal stimulation] is often found in demyelinating neuropathies,6 including inflammatory neuropathies and degenerative neuropathies, such as “liability to pressure neuropathy.”5 There is experimental evidence that a transient conduction block can occur in rats after ischemic lesions of peripheral nerves are induced either by ligation of arterial vessels supplying nerve trunks,3,9 or by injection of arachidonic acid into peripheral arterial vessels.11,16 Conduction block has also recently been described in cases with necrotizing vasculitis.15 To date, however, no example of a reversible conduction block has been reported in human ischemic neuropathy.
Effect of clenbuterol on protease activitiies and protein levels in rat muscle
Authors: Mantle David , Delday Margaret I. , Maltin Charlotte A. 
Published: January 2005

AbstractTo elucidate the biochemical mechanism by which the sympathomimetic agent clenbuterol promotes skeletal muscle growth, We have determined the activity of a range of proteolytic enzyme types (acid, neutral and alkaline proteinases and peptidases), together with the levels of souble and structural proteins (via SDS‐polyacrylamide) in 5 inner‐vated and denervated muscle types from for any enzyme type in any muscle (in‐nervated or denervated) following clenbuterol treatment; however, one enzyme, arginyl aminopeptidase, showed a small but consistent decrease in acticvity in all of the innervated muscles investigated. Smilar fractionation muscle types (innervated or denervated) in control or clenbuterol‐treated animals, with the exception of one band (subunit molecular mass 18 kD). We conclude that the anabolic action of clenbuterol in promoting skeletal muscle growth does not occur via downregulation of protease activity, or increase in levels of individual muscle proteins.