bluuebunny/crossref_metadata_2025_split huggingface dataset:
Direct monitoring of coronary artery motion with cardiac fat navigator echoes
Authors: Nguyen Thanh D. , Nuval Anthony , Mulukutla Suresh , Wang Yi 
Published: July 2003

AbstractNavigator echoes (NAVs) provide an effective means of monitoring physiological motion in magnetic resonance imaging (MRI). Motion artifacts can be suppressed by adjusting the data acquisition accordingly. The standard pencil‐beam NAV has been used to detect diaphragm motion; however, it does not monitor cardiac motion effectively. Here we report a navigator approach that directly measures coronary artery motion by exciting the surrounding epicardial fat and sampling the signal with a k‐space trajectory sensitized to various motion parameters. The present preliminary human study demonstrates that superior‐inferior (SI) respiratory motion of the coronary arteries detected by the cardiac fat NAV highly correlates with SI diaphragmatic motion detected by the pencil‐beam NAV. In addition, the cardiac fat navigator gating is slightly more effective than the diaphragmatic navigator gating in suppressing motion artifacts in free‐breathing 3D coronary MR angiography (MRA). Magn Reson Med 50:235–241, 2003. © 2003 Wiley‐Liss, Inc.
Steady‐state imaging for visualization of endovascular interventions
Authors: Martin Alastair J. , Weber Oliver M. , Saeed Maythem , Roberts Timothy P.L. 
Published: July 2003

AbstractSteady‐state imaging techniques offer the potential to couple high spatial and temporal resolution with good signal‐to‐noise ratio (SNR), which makes them ideally suited for fluoroscopic applications. However, disturbance of the steady state can result in artifacts and substantially reduced signal levels. In this study the use of steady‐state imaging techniques was investigated as a means of guiding endovascular interventions with fluoroscopic MRI. Devices containing localized susceptibility defects were shown to disturb the steady‐state signal of spins that pass through the magnetic field disturbances. It was demonstrated that these effects are appreciable and can make delineation of interventional devices difficult in the presence of flow. T1‐shortening contrast agents were shown to dramatically reduce these effects by reducing the time taken to achieve steady state. The addition of a blood pool agent in an in vivo model was found to be necessary for adequate visualization of a dysprosium‐marked catheter. Magn Reson Med 50:434–438, 2003. © 2003 Wiley‐Liss, Inc.
Combination of transfection agents and magnetic resonance contrast agents for cellular imaging: Relationship between relaxivities, electrostatic forces, and chemical composition
Authors: Kalish H. , Arbab A.S. , Miller B.R. , Lewis B.K. , Zywicke H.A. , Bulte J.W.M. , Bryant L.H. , Frank J.A. 
Published: July 2003

AbstractThe purpose of this study was to investigate the changes in electrostatic and magnetic resonance (MR) properties observed when MR contrast agents (CAs) (Feridex®, MION‐46L, or G5‐dendrimer‐DOTA‐Gd) are combined with transfection agents (TAs) under various conditions for use as a CA‐TA complex basis for cellular labeling and MRI. CAs were incubated with various classes of TAs for 0–48 hr in solutions of varying concentrations and pH values. NMR relaxation rates (1/T1, 1/T2), MRI and zeta potential (ZP) of CA‐TA solutions were measured. TAs decreased the 1/T1 and 1/T2 of G5‐DOTA‐Gd, Feridex®, and MION‐46L by 0–95%. Altering the pH of G5‐DOTA‐Gd‐TA decreased the T1‐weighted signal intensity (SI) on MRI from 0 to 78%. Measured ZP values for G5‐DOTA‐Gd, Feridex®, and MION‐46L were −51, −41, and −2.0 mV, respectively. The TA LV had a negative ZP, while the other TAs had ZPs ranging from +20 to +65 mV. The alteration of the ZP and NMR relaxivities of the MR CAs, Feridex®, MION‐46L, and G5‐DOTA‐Gd by TAs has been demonstrated. These results enhance our understanding of the relationship between electrostatic and MR properties. Magn Reson Med 50:275–282, 2003. Published 2003 Wiley‐Liss, Inc.
Lyme disease and the peripheral nervous system
Authors: Halperin John J. 
Published: July 2003

AbstractLyme disease, the multisystem infectious disease caused by the tick‐borne spirochete Borrelia burgdorferi, causes a broad variety of peripheral nerve disorders, including single or multiple cranial neuropathies, painful radiculopathies, and diffuse polyneuropathies. Virtually all appear to be varying manifestations of a mononeuropathy multiplex. Diagnosis requires that the patient should have had possible exposure to the only known vectors, Ixodes ticks, and also have either other pathognomonic clinical manifestations or laboratory evidence of exposure. Treatment with antimicrobial regimens is highly effective. The mechanism underlying these neuropathies remains unclear, although interactions between anti‐Borrelia antibodies and several peripheral nerve constituent molecules raise intriguing possibilities. Muscle Nerve 28: 133–143, 2003
The H‐reflex as a tool in neurophysiology: Its limitations and uses in understanding nervous system function
Authors: Misiaszek John E. 
Published: July 2003

AbstractThe Hoffmann reflex (H‐reflex) is extensively used as both a research and clinical tool. The ease with which this reflex can be elicited in several muscles throughout the body makes it an attractive tool. This review discusses some of the important limitations in using the H‐reflex. In particular, the inaccurate but widely held assumptions that the H‐reflex (1) represents the monosynaptic reflex of the Ia afferent onto homonymous motoneurons, and (2) can be used to measure motoneuronal excitability are addressed. The second part of this review explores the utility of the H‐reflex as a neural probe in neurophysiology and motor control research. Applications ranging from the investigation of the functional organization of neural circuitry to the study of adaptive plasticity in spinal structures in health and disease suggest that the H‐reflex will continue to be an extensively used tool in motor control neurophysiology. Muscle Nerve 28: 144–160, 2003
Paramyotonia congenita due to a de novo mutation: A case report
Authors: Fukudome Takayasu , Izumoto Hajime , Goto Hirofumi , Matsuo Hidenori , Yoshimura Toshiro , Sakoda Shun‐Ichi , Shibuya Noritoshi 
Published: July 2003

AbstractA Japanese man with a negative family history of paramyotonia congenita (PMC) was evaluated for symptoms of cold‐induced weakness and stiffness. Exercise testing revealed findings characteristic of PMC, and a genetic analysis was therefore performed. A well‐known sodium channel mutation for PMC (T1313M) was identified in the patient, but was absent in his biological parents. These data demonstrate the occurrence of a de novo mutation, suggesting that evaluation for PMC should be performed in patients with typical symptoms even if the family history is negative. Muscle Nerve 28: 232–235, 2003
Effects of imagery motor training on torque production of ankle plantar flexor muscles
Authors: Zijdewind Inge , Toering Sjoukje T. , Bessem Bram , van der Laan Occo , Diercks Ron L. 
Published: July 2003

AbstractThe aim of this study was to investigate in control subjects the effect of imagery training on the torque of plantar‐flexor muscles of the ankle. Twenty‐nine subjects were allocated to one of three groups that performed either imagery training, low‐intensity strength training, or no training (only measurements). The low‐intensity training served as an attention control group. Plantar‐flexor torques were measured before, during, directly after, and 4 weeks after the training period. At the end of a 7‐week training program, significant differences were observed between the maximal voluntary torque production of the imagery training group (136.3 ± 21.8% of pretraining torque) vs. the low‐intensity training group (112.9 ± 29.0%; P < 0.02) and the control group (113.6 ± 19.2%; P < 0.02). The results of this study show that imagery training of lower leg muscles significantly increased voluntary torque production of the ankle plantar‐flexor muscles and that the force increase was not due to nonspecific motivational effects. Such muscle strengthening effects might be beneficial in rehabilitation for improving or maintaining muscle torque after immobilization. Muscle Nerve 28: 168–173, 2003
Changes in neuromuscular function after training by functional electrical stimulation
Authors: Marqueste Tanguy , Hug François , Decherchi Patrick , Jammes Yves 
Published: July 2003

AbstractWe examined whether the neuromuscular function of rectus femoris (RF) and flexor digitorum brevis (FDB) in humans was modified after a 6‐week training period of functional electrical stimulation (FES), and whether any effects persisted at the end of a 6‐week post‐FES recovery period. In both the stimulated and contralateral nonstimulated muscles, we recorded the muscle force, surface electromyogram, and M wave, and also measured the root mean square (RMS) and the median frequency (MF) during static contraction sustained until exhaustion at 60% of maximal voluntary contraction (MVC). FES was performed with symmetric biphasic pulses, with a ramp modulation of both the stimulation frequency and pulse duration. No changes in MCV and endurance time to exhaustion occurred in nonstimulated muscles, whereas a significant MVC increase occurred immediately after FES in RF (+14 ± 5%) and FDB (+13 ± 5%), these effects persisting 6 weeks after the end of FES. In FDB, FES also elicited a significant increase in endurance time to exhaustion (+18 ± 7%). The M‐wave characteristics never varied after FES, but a marked attenuation occurred in the MF decrease and the RMS increase measured at endurance time to sustained 60% MVC, especially in FDB, which contains the higher proportion of type II fibers. These data indicate that FES improves muscle function and elicits changes in central muscle activation. The benefits of FES were greater in FDB, which is highly fatigable, and persisted for at least a 6‐week period. Muscle Nerve 28: 181–188, 2003
Progressive arm weakness and tonic hand spasm from multifocal motor neuropathy in the brachial plexus
Authors: Veltkamp R. , Krause M. , Schranz C. , Meinck H.‐M. 
Published: July 2003

AbstractA 50‐year‐old waitress presented with a 10‐year history of progressive weakness in her right arm without atrophy and with tonic hand spasms suggesting a central motor disorder. Electromyography, however, disclosed chronic neurogenic changes including fasciculations and atypical cramps. Isolated motor conduction block in the right brachial plexus suggested a variant of multifocal motor neuropathy. Strength recovered and cramps disappeared after intravenous immunoglobulins. Motor neuropathies may thus manifest with features of central motor disorders. Muscle Nerve 28: 242–245, 2003
Decremental response of the nasalis and hypothenar muscles in myasthenia gravis
Authors: Niks Erik H. , Badrising Umesh A. , Verschuuren Jan J. , van Dijk J. Gert 
Published: July 2003

AbstractRepetitive nerve stimulation (RNS) is a standard diagnostic procedure in myasthenia gravis (MG). Although RNS sensitivity is highest in weak muscles, RNS is easier to perform in distal muscles that are often not affected. Twenty‐five patients with MG were assessed to compare the sensitivity of RNS of the nasalis muscle to that of the hypothenar muscles. Abnormal decrement was found in hypothenar muscles in 9 patients (36%) and in the nasalis muscle in 13 patients (52%). RNS of the nasalis muscle appeared more useful to detect abnormal neuromuscular transmission in patients with oculobulbar MG (5 of 5) than hypothenar RNS (1 of 5). In patients with generalized MG, hypothenar muscles had a similar yield of abnormal RNS tests. Muscle Nerve 28: 236–238, 2003
Changing stimulation patterns improves performance during electrically elicited contractions
Authors: Scott Wayne B. , Binder‐Macleod Stuart A. 
Published: July 2003

AbstractThe clinical efficacy of functional electrical stimulation (FES) is limited by the rapid onset of fatigue. FES applications use electrical stimuli separated by regular interpulse intervals (constant‐frequency trains or CFTs) to activate muscles. However, doublet‐frequency trains (DFTs) may produce greater forces than CFTs, but also produce more fatigue. DFTs contain a series of doublets, two pulses separated by a short (5‐ms) interpulse interval. We hypothesized that a combination of CFTs followed by DFTs would improve performance compared to either train type alone. Quadriceps muscles of 15 normal subjects were fatigued with either 150 DFTs, or initially fatigued with CFTs until the targeted isometric force was no longer produced and then switched to DFTs. The combination reached the targeted isometric force (mean ± SEM) more times (59.80 ± 4.03) than either the CFTs alone (51.20 ± 3.50) or DFTs alone (55.33 ± 3.81). This finding suggests that combining train types may be a useful strategy to offset the rapid fatigue that persons with neurological dysfunction, such as spinal cord injury, experience when using FES. Muscle Nerve 28: 174–180, 2003
Evaluation of morphological and functional regeneration of rat nerve–muscle units after temporary and permanent tubulization
Authors: Odaka Mitsuaki , Uchiyama Yoshiyasu , Oka Yoshinori , Tamaki Tetsuro 
Published: July 2003

AbstractWe compared the ability of temporary and permanent tubing to achieve morphological and functional recovery of nerve–muscle units, following experimental nerve transection (8‐mm gap) in rat tibial nerve. Electrical stimulation of the sciatic nerve was used to analyze tension output, evoked electromyogram and conduction‐transmission time (CTT) of denervated nerve–muscle units. Morphological analysis of the nerve and muscle was also performed. Within 6 weeks, the nerve gap had been bridged by a thin nerve trunk, and a few myelinated fibers were observed, although there was still no functional recovery. The rats were divided into two groups: permanent tubing (PT) and temporary tubing (TT; tubing subsequently removed). At 10 weeks after the operation, the TT group showed apparently greater thickness of regenerated nerve trunks, significantly higher tension output of plantar flexors, shorter CTT, and heavier muscle mass. These results were consistent with the presence of myelinated fibers in the regenerated nerve trunks, as shown histologically. Thus, removal of the silicone chamber results in faster and better recovery than tubing left permanently in place. Muscle Nerve 28: 194–203, 2003
Monophasic and biphasic stimulation evoke different responses
Authors: Field‐Fote Edelle C. , Anderson Brent , Robertson Valma J. , Spielholz Neil I. 
Published: July 2003

AbstractIn 31 subjects, psychophysiological sensory perception threshold and the waveform of orthodromic sensory nerve action potentials (SNAPs) produced by constant‐current 100‐μs monophasic negative pulses were compared to those produced by biphasic (negative–positive) symmetrical pulses (100‐μs per phase). In addition, the effects of 200‐μs monophasic negative pulses were studied. Graded stimuli were delivered to the index finger, and SNAPs were recorded over the median nerve at the wrist. Perception threshold was significantly different among the three conditions. Furthermore, in 26 subjects, at the lower intensities at which SNAPs first appeared, the evoked potential waveform had two small negative phases with biphasic stimuli, but a single negative phase in response to monophasic pulses. At higher stimulus intensities, all SNAPs had a single large negative phase regardless of the stimulus. These perception and waveform findings suggest that, contrary to historical belief, the trailing positive phase of a biphasic pulse has a stimulating effect at low stimulus intensities. Muscle Nerve 28: 239–241, 2003
Motor unit number estimate of distal and proximal muscles in Charcot–Marie–Tooth disease
Authors: Lewis Richard A. , Li Jun , Fuerst Darren R. , Shy Michael E. , Krajewski Karen 
Published: July 2003

AbstractIn order to determine the utility of motor unit number estimation (MUNE) in assessing axonal loss in chronic inherited neuropathies, we determined MUNEs in 54 patients with Charcot–Marie–Tooth (CMT) disease (29 patients with CMT‐1A, 13 with CMT‐X, and 12 with CMT‐2) by using spike‐triggered averaging (STA) of the ulnar‐innervated abductor digiti minimi/hypothenar muscles (ADM) and the musculo‐cutaneous innervated biceps/brachialis (BB) muscles. MUNEs were analyzed in relationship to the corresponding compound muscle action potential (CMAP) amplitudes as well as to clinical strength. Proximal muscles, which appeared strong clinically, had evidence of chronic denervation/reinnervation, although to a lesser extent than weak distal hand muscles, supporting the concept that axonal loss in CMT occurs in a length‐dependent fashion. The reduction in ADM‐MUNE strongly correlated with clinical weakness in the hand. Both the ADM‐MUNE and BB‐MUNE were abnormal more often than CMAP amplitude, probably reflecting extensive motor unit reconfiguration and enlargement that maintains CMAP amplitude despite severe motor unit loss. This study suggests that MUNE can assess motor unit loss in CMT and may better reflect axonal loss than CMAP amplitude. The STA technique of MUNE may be useful in longitudinal studies of proximal and distal motor unit changes in CMT. Muscle Nerve 28: 161–167, 2003
Dispersion of the distal compound muscle action potential in chronic inflammatory demyelinating polyneuropathy and carpal tunnel syndrome
Authors: Cleland James C. , Logigian Eric L. , Thaisetthawatkul Pariwat , Herrmann David N. 
Published: July 2003

AbstractMedian neuropathy at the wrist can confound the electrodiagnosis of chronic inflammatory demyelinating polyneuropathy (CIDP), since both conditions can prolong median distal motor latency. Dispersion of the distal CMAP (DCMAP) has recently emerged as a potentially useful adjunct in the electrodiagnosis of CIDP, with good specificity in distinguishing CIDP from certain axon‐loss disorders. However, it is uncertain whether focal compression neuropathies produce dispersion of the DCMAP in a manner similar to CIDP. In this study we compared median DCMAP duration in 27 patients with CIDP and 86 with carpal tunnel syndrome, using 39 patients with non‐neuropathic musculoskeletal pain syndromes as electrophysiologic controls. We found that, in contrast to CIDP, dispersion of the median DCMAP is uncommon, even in advanced carpal tunnel syndrome, being seen in only 8 of 103 (7.8%) hands. Although the pathophysiologic reasons for a differential effect of focal compression‐mediated demyelination and multifocal immune‐mediated demyelination (CIDP) on DCMAP duration are uncertain, our findings suggest that the presence of dispersion of the median DCMAP may prove useful in distinguishing immune‐mediated demyelination from compression neuropathy alone. Muscle Nerve 28: 189–193, 2003
Noninactivating, tetrodotoxin‐sensitive Na+ conductance in peripheral axons
Authors: Tokuno Hajime A. , Kocsis Jeffery D. , Waxman Stephen G. 
Published: July 2003

AbstractA noninactivating, persistent sodium current has been demonstrated previously in dorsal root ganglia neurons and in rat optic nerve. We report here that Na+ channel blockade with tetrodotoxin (TTX) in isolated dorsal and ventral roots elicits membrane hyperpolarization, suggesting the presence of a persistent Na+ current in peripheral axons. We used a modified sucrose‐gap chamber to monitor resting and action potentials and observed a hyperpolarizing shift in the nerve potential of rat dorsal and ventral roots by TTX. The block of transient inward Na+ currents was confirmed by the abolition of compound action potentials (CAPs). Moreover, depolarization of nerve roots by elevating extracellular K+ concentrations to 40 mM eliminated CAPs but did not significantly alter TTX‐induced hyperpolarizations, indicating that the persistent Na+ currents in nerve roots are not voltage‐dependent. Tetrodotoxin‐sensitive persistent inward Na+ currents are present in both dorsal and ventral root axons at rest and may contribute to axonal excitability. Muscle Nerve 28: 212–217, 2003
Preferential motor reinnervation in the mouse: Comparison of femoral nerve repair using a fibrin sealant or suture
Authors: Robinson Grant A. , Madison Roger D. 
Published: July 2003

AbstractPrevious studies in rat femoral nerve demonstrated that regenerating motor axons preferentially reinnervate a nerve branch to muscle as opposed to skin, a process that has been termed preferential motor reinnervation (PMR). This process has not been previously reported in the mouse, where the use of transgenic animals could be a powerful tool to study the basic mechanisms that determine accuracy of regenerating motor axons. In the mouse, we applied the same nerve repair (suture) and retrograde labeling strategies that successfully demonstrated PMR in the rat femoral nerve but surprisingly were unable to demonstrate PMR. However, if the mouse femoral nerve was repaired with a fibrin sealant, PMR was readily apparent, suggesting that PMR in the mouse is dependent on the method of nerve repair. Muscle Nerve 28: 227–231, 2003
Axonal pharyngeal‐cervical‐brachial variant of Guillain–Barré syndrome without Anti‐GT1a IgG antibody
Authors: Arai Motomi , Susuki Keiichiro , Koga Michiaki 
Published: July 2003

AbstractWe report two cases of pharyngeal‐cervical‐brachial (PCB) variant of Guillain–Barré syndrome (GBS). The patients developed dysphagia and weakness of the neck and arms subsequent to Campylobacter jejuni infection. Oropharyngeal palsy recovered poorly. Electrophysiological findings demonstrated axonal conduction failure. Anti‐GD1a immunoglobulin G (IgG) antibody was detected in one case, and anti‐GM1b IgG antibody in another. Anti‐GT1a IgG and immunoglobulin M (IgM) antibodies were negative in both cases. The current cases suggest that the PCB and axonal variants of GBS form a continuous spectrum from the viewpoint of electrophysiological studies as well as antiganglioside serology. Muscle Nerve 28: 246–250, 2003
Decomposition‐based quantitative electromyography: Methods and initial normative data in five muscles
Authors: Doherty Timothy J. , Stashuk Daniel W. 
Published: July 2003

AbstractQuantitative electromyographic (EMG) techniques provide clinically useful information to aid in the diagnosis and follow the course or response to treatment of diseases affecting the motor system. The purpose of this study was to describe a decomposition‐based quantitative electromyography method (DQEMG) designed to obtain clinically applicable information relating to motor unit
potential (MUP) size and configuration, and motor unit (MU) firing characteristics. Additionally, preliminary normative data were obtained from the deltoid, biceps brachii, first dorsal interosseous, vastus medialis, and tibialis anterior muscles of 13 control subjects. DQEMG was capable of efficiently and accurately extracting MUP data from complex interference patterns during mild to moderate contractions. MUP amplitude, surface‐detected MUP (S‐MUP) amplitude, MUP duration, number of phases, and MU firing frequencies varied significantly across muscles. The mean parameter values for the individual muscles studied were similar to previous reports based on other quantitative methods. The main advantages of this method are the speed of data acquisition and processing, the ability to obtain MUPs from MUs with low and higher recruitment thresholds, and the ability to obtain both S‐MUP or macro‐MUP data as well as MU firing rate information. Muscle Nerve 28: 204–211, 2003