bluuebunny/crossref_metadata_2025_split huggingface dataset:
Case of the month. Disseminated histoplasmosis presenting as myositis and fasciitis in a patient with dermatomyositis
Authors: Voloshin Denise K. , Lacomis David , McMahon Deborah 
Published: January 2005

AbstractA 54‐year‐old man with dermatomyositis initially responsive to corticosteroids and methotrexate developed severe myalgias, increasing weakness, and fevers. Laboratory studies were suggestive of disseminated histoplasmosis, and muscle biopsy revealed myositis, fasciitis, and yeast in the perimysial connective tissue. Histoplasma capsulatum was cultured from skeletal muscle. Despite antifungal therapy, necrotizing fasciitis progressed to gluteal abscess formation. Disseminated histoplasmosis may present atypically in immunocompromised hosts as fasciitis and myositis. Patients with dermatomyositis could be particularly vulnerable to soft tissue invasion by fungi due to their underlying microangiopathy. © 1995 John Wiley & Sons, Inc.
Reliability of measurements of muscle strength and voluntary activation using twitch interpolation
Authors: Allen G. M. , Gandevia S. C. , McKenzie D. K. 
Published: January 2005

AbstractWe investigated the reproducibility of measurements of maximal voluntary torque and maximal voluntary activation using twitch interpolation. On 5 days, each of 5 subjects performed 10 maximal voluntary isometric contractions of their elbow flexors. Single supramaximal stimuli were delivered over biceps brachii at the measured peak torque during each effort, and in the relaxed muscle 5 s later. A voluntary activation score was calculated from the size of twitches evoked by the stimuli (resolution < 0.15 Nm). Although all subjects were able to drive the stimulated elbow flexor muscles maximally in some trials, they did not do so in 75% of all contractions. Maximal voluntary torques did not vary significantly within a subject between sessions. There were consistent differences in the level of maximal voluntary activation between subjects (P < 0.01), but no differences in voluntary activation within an individual across days in 4 of 5 subjects. Failure to drive the stimulated elbow flexor muscles maximally was not associated with inadvertent co‐contraction of the antagonist muscles. © 1995 John Wiley & Sons, Inc.
Neuromuscular disorders in systemic malignancy and its treatment
Authors: Stübgen Joerg‐Patrick 
Published: January 2005

AbstractNeuromuscular dysfunction in patients with known or suspected malignancy has three basic etiologies: (1) a direct effect of the neoplasm, either by compression or infiltration; (2) a “remote,” or paraneoplastic, effect of cancer; or (3) a side effect of anticancer treatment, radiation or chemotherapy. A variety of clinical features or syndromes are due to damage either at the level of the neuron (anterior horn cell or dorsal root ganglion neuron), nerve root(S), brachial or lumbosacral plexus, peripheral nerve (motor, sensory, and/or autonomic), neuromuscular junction, or muscle. A complex clinical picture evolves when dysfunction in due to more than one cause at more than one anatomical site. © 1995 John Wiley & Sons, Inc.
Dynamical analysis of neuromuscular transmission jitter
Authors: Gilchrist James M. , Perrone Michael , Ross John 
Published: January 2005

AbstractUtilizing prolonged axonal stimulation single fiber EMG, neuromuscular transmission becomes a time‐series of interpotential intervals (IPIs). In this form, the underlying processes of neuromuscular transmission can be studied using standard numerical techniques to determine whether these processes can be described by a simple mathematical model. In particular, neuromuscular transmission jitter can be examined in this way. In this article, we attempt to determine whether healthy jitter is noise or deterministic chaos. The presence of deterministic chaos was assessed by analysis of the IPI time‐series using visual inspection of both phase‐space plots and their principal component dimensions, and using the Grassberger–Procaccia algorithm to determine the correlation dimension of the time‐series dynamics. These graphical and mathematical techniques provided little evidence for the existence of deterministic chaos. Linear autoregression time‐series prediction also failed to account for the variability of the data and IPI histograms exhibited simple gaussian distributions. These results suggest normal neuromuscular transmission jitter is the result of intrinsic noise. © 1995 John Wiley & Sons, Inc.
Characterization of the glycolysis in lactate dehydrogenase‐A deficiency
Authors: Miyajima Hiroaki , Takahashi Yoshitomo , Kaneko Eizo 
Published: January 2005

AbstractRecurrent rhabdomyolysis due to decreased glycolysis occurred during strenuous exercise by patients with lactate dehydrogenase‐A subunit (LDH‐A; muscle) deficiency. We report the glycolytic features of 4 patients from 2 families in whom the severity of the disease differed. There was no difference in the gene abnormality. The enzyme activity of LDH in the muscle was less than 5% that of the control value. Glycolysis in the muscle showed that the respective sums of the pyruvate and lactate levels in the patients with mild and severe symptoms were reduced to approximately 65% and 35% that of the control value. Comparable amounts of glycerol 3‐phosphate were produced. Glycerol 3‐phosphate dehydrogenase activity in the muscles of patients with mild symptoms was three times the control value. These findings suggest that the disease severity in our patients may be related to the degree of NADH reoxidation by glycerol 3‐phosphate dehydrogenase substituting for LDH. © 1995 John Wiley & Sons, Inc.
Number and relative size of thenar motor units estimated by an adapted multiple point stimulation method
Authors: Wang François‐Charles , Delwaide Paul J. 
Published: January 2005

AbstractAn adapted multiple point stimulation (AMPS) method is described for estimating the number and relative size of thenar motor units. With this method, the median nerve was stimulated at various sites from the wrist to the elbow. To avoid alternation, only two or three clearly identifiable surface‐recorded motor unit action potentials (S‐MUAPs) were recruited at each point by incremental stimulation. A total of 10 S‐MUAPs, eleicited from four to five distinct stimulatin points, was used to calculate the average S‐MUAP size. By dividing the maximum M‐potential size by that value, a motor unit number estimate (MUNE) was derived. In 59 healthy volunteers, from 19 to 87 years old, the mean average S‐MUAP size was 87 ± 27.6 μV. ms and the mean MUNE was 278 ± 113 motor units. When performed repeatedly, the results were reproducible. The number of motor units declined exponenetially with age while average S‐MUAP sized increased only moderately. To assess the validity of the AMPS method, its results were correlated with those obtained using the F‐response technique. The correlation coefficient was 0.83 (P < 0.001). © 1995 John Wiley & Sons, Inc.
Increased laminin a expression in regenerating myofibers neuromuscular disorders
Authors: Mundegar Rustam R. , Von Oertzen Joachim , Zierz Stephan 
Published: January 2005

AbstractLaminin is a basement membrane (BM) glycoprotein composed of three of five subunits, the A, M, B1, B2, and the S chain. Four forms of laminin, A‐B1‐B2, A‐S‐B2, M‐B1‐B2, and M‐S‐B2, have been identified. Laminin is implicated in various biological processes such as cell adhesion and differentiation. We studied immunohistochemically the expression of the four laminin subunits A, M, B1, B2 as well as of neural cell adhesion molecule (N‐CAM, CD56), a marker of regenerating myofibers, in various neuromuscular disorders. In normal muscle, the predominant subunits of myofiber laminin were M, B1, and B2. The A chain was only faintly expressed in myofiber BM. In inflammatory myopathies and dystrophinopathies myofiber laminin A expression was greatly increased. An average of 80% and 63% of laminin A–positive myofibers in inflammatory myopathies and dystrophinopathies, respectively, were additionally CD56 positive. Laminin A and CD56 expression in denervating diseases and mitochondrial myopathies were negligible. Expression of M, B1, and B2 subunits did not seem to be altered in the diseased conditions examined above. The data suggest that laminin A is upregulated in inflammatory myopathies and dystrophinopathies and, most markedly in regenerating myofibers. © 1995 John Wiley & Sons, Inc.
Regeneration across preserved peripheral nerve grafts
Authors: Evans Peter J. , Mackinnon Susan E. , Best Timothy J. , Wade Judith A. , Awerbuck David C. , Makino Akira P. , Hunter Daniel A. , Midha Rajiv 
Published: January 2005

AbstractThe potential to store nerve grafts for a prolonged period of time was assessed in a rat sciatic nerve model. Three‐centimeter syngeneic nerve grafts were stored in Belzer/University of Wisconsin cold storage solution at different temperatures (5°C, 22°C, or 37°C) for varying time periods (6 h, 24 h, or 3 weeks) prior to transplantation. Functional assessment using serial walking track analyses revealed no difference between storage times and temperatures. At 14 months postengraftment, the conduction velocities and the number of myelinated fibers that had regenerated across all grafts stored at 5°C for all time periods tested were superior to grafts stored at either 22°C or 37°C. Nerve grafts stored for up to 3 weeks at 5°C acted as effective conduits for proximal regenerating fibers and resulted in histologic, electrophysiologic, and functional results equivalent to fresh nerve grafts. Nerve graft storage may be applicable to nerve allografts and potentially provide allograft material that requires reduced or no associated host immunosuppression.© 1995 John Wiley & Sons, Inc.
Multi‐motor unit action potential analysis (MMA)
Authors: Nandedkar Sanjeev D. , Barkhaus Paul E. , Charles Alison 
Published: January 2005

AbstractWe have developed an algorithm, called multi–motor unit action potential analysis (MMA), to aid quantification in routine needle EMG examination. In only 5–8 min, it was possible to extract, analyze, and validate 20 motor unit action potentials (MUAPs). In the biceps muscle of normal subjects, the MUAP measurements are compared with measurements using manual, triggered averaging, automatic decomposition, and other MMA algorithms described in the literature. The mean values of MUAP features by MMA fell between the extreme limits obtained from the amplitude‐triggered method and the manual method described in the literature. In patients, the results are consistent with routine EMG and similar to those results described in the literature. Fast acquisition and analysis of MUAPs as well as interference pattern (IP) analysis make this technique useful to document EMG abnormalities in routine needle examination.© 1995 John Wiley & Sons, Inc.
The relation between conduction velocity and axonal length
Authors: Zwarts Machiel J. , Guechev Antonin 
Published: January 2005

AbstractMotor evoked potentials (MEPs) obtained by electrical root stimulation and F waves were used to examine the proximal nerve conduction velocity (CV) to tibialis anterior (TA), extensor digitorum brevis (EDB), flexor carpi radialis (FCR), and abductor pollicis brevis (APB) muscles in 40 humans. By subtracting motor latencies obtained by stimulating the peripheral nerve at the same point from the F‐wave and MEP latencies, we could measure the CV over identical proximal segments. It was found that proximal CV to TA and FCR was significantly higher than to EDB and APB, respectively. Combining the data of the proximal CV to all four muscles in relation with axonal length resulted in a highly significant inverse relationship (r2 = 0.77). Thus the axonal length explained to a large extent the higher CV of the arm nerves and also the inverse relation between body height and CV. The distal CV was always lower than proximal CV; however, there was no support for an additional effect of this gradient in explaining the relationship between CV and height since it was constant for all body heights. © John Wiley & Sons, Inc.
Superoxide dismutases of muscle in mitochondrial encephalomyopathies
Authors: Ohkoshi Norio , Mizusawa Hldehlro , Shiraiwa Nobuko , Shoji Shin'Ichi , Harada Katsutoshi , Yoshizawa Kazuo 
Published: January 2005

AbstractLmmunohistochemical analyses were made of the superoxide dismutases (Mn‐SOD and CuiZn‐SOD) in biopsied muscles from 7 patients with mitochondrial encephalomyopathies that included mitochondrial encephalomyopathy, lactic acidosis and strokelike episodes (MELAS), and chronic progressive external ophthalmoplegia (CPEO). Mn‐SOD mainly was present in the subsarcolemmal region, but it also was found in a coarsely granular, reticular, or diffuse pattern of staining within the muscle fibers. These Mn‐SOD‐positive fibers corresponded almost completely to the ragged‐red fibers. The immunoreaction for CuiZn‐SOD was weakly positive in some of the muscle fibers positive for Mn‐SOD. In CPEO, Mn‐SOD‐positive fibers predominantly showed decreased cytochrome c oxidase (COX) activity. In MELAS, Mn‐SOD‐positive fibers tended to be stained deeply for COX although a few were COX‐negative. These findings suggest that Mn‐SOD‐positive fibers can be used to make a differential diagnosis between CPEO and MELAS and that in mitochondrial encephalomyopathies Mn‐SOD in the raggedred fibers may protect against oxidative stress. © John Wiley & Sons, Inc.
Evidence of an abnormal intramuscular component of fatigue in multiple sclerosis
Authors: Sharma Khema R. , Kent‐Braun Jane , Mynhier Mark A. , Weiner Michael W. , Miller Robert G. 
Published: January 2005

AbstractThe goals of this study were to investigate muscle fatigue in patients with multiple sclerosis (MS), and to determine the relationships between muscle fatigue, clinical status, and perceived fatigue. The fatigability of the anterior tibial muscle was quantitated in patients and controls during 9 min of intermittent stimulation (used to eliminate central sources of muscle fatigue). During exercise, the decline in tetanic force, phosphocreatine, and intracellular pH was greater in patients than in controls. The compound muscle action potential amplitude did not decrease during exercise, indicating that there was no failure of neuromuscular transmission during fatigue. Thus, the excessive fatigue in MS developed from sources beyond the muscle membrane. Following exercise, the recovery of tetanic force was delayed in patients (a pattern that suggests abnormal excitation–contraction coupling), whereas the recovery of metabolites was complete in both groups. Muscular fatigue was correlated with clinical disability but not with perceived fatigue. These results suggests that fatigue in MS has both central (perception, upper motor neuron dysfunction) and peripheral (impaired metabolism and excitation–contraction coupling) components.© 1995 John Wiley &Sons, Inc.
Spinal motor neuron excitability during the cutaneous silent period
Authors: Leis A. Arturo , Štětkářová Ivana , Berić Aleksandar , Stokić Dobrivoje S. 
Published: January 2005

AbstractThe physiologic mechanisms generating the cutaneous silent period (CSP) remain uncertain. It is not known whether the CSP occurs because of inexcitability of the spinal motor neuron. We, therefore, assessed excitability of the motor neuron during the CSP using F‐wave responses. H‐reflexes were also elicited during the CSP. Electrical stimulation to the fifth digit produced the CSP in the voluntarily contracting abductor pollicis brevis muscle (APB). Median nerve stimulation at the wrist elicited control F or H responses during isometric APB contraction (condition 1) and in resting muscle (condition 2). Control amplitudes were compared to those elicited in the midst of the CSP. In Condition 1, F‐wave amplitudes and frequency during the CSP were unchanged compared with controls. However, F‐waves were increased in amplitude and frequency during the CSP (P < 0.001) relative to responses elicited in resting muscle (condition 2). H‐reflexes during the CSP were suppressed (P < 0.001) compared with controls elicited during contraction (condition 1), but facilitated relative to the resting state (condition 2) in which no H‐reflexes were elicitable. We conclude that spinal motor neurons remain excitable to antidromic volleys at the same time that the corticospinal volley is inhibited to produce the CSP. Moreover, motor neuron excitability appears to be increased during the CSP compared to the relaxed state. © 1995 John Wiley & Sons, Inc.
Applications of manganese‐enhanced magnetic resonance imaging (MEMRI) to image brain plasticity in song birds
Authors: Van der Linden Annemie , Van Meir Vincent , Tindemans Ilse , Verhoye Marleen , Balthazart Jacques 
Published: January 2005

AbstractThe song control system of song birds is an excellent model for studying brain plasticity and has thus far been extensively analyzed by histological and electrophysiological methods. However, these approaches do not provide a global view of the brain and/or do not allow repeated measures, which are necessary to establish correlations between alterations in neural substrate and behavior. Application of in vivo manganese‐enhanced MRI enabled us for the first time to visualize the song control system repeatedly in the same bird, making it possible to quantify dynamically the volume changes in this circuit as a function of seasonal and hormonal influences. In this review, we introduce and explore the song control system of song birds as a natural model for brain plasticity to validate a new cutting edge technique, which we called ‘repeated dynamic manganese enhanced MRI’ or D‐MEMRI. This technique is based on the use of implanted permanent cannulae—for accurate repeated manganese injections in a defined target area—and the subsequent MRI acquisition of the dynamics of the accumulation of manganese in projection brain targets. A compilation of the D‐MEMRI data obtained thus far in this system demonstrates the usefulness of this new method for studying brain plasticity. In particular it is shown to be a perfect tool for long‐term studies of morphological and functional responses of specific brain circuits to changes in endocrine conditions. The method was also successfully applied to obtain quantitative measures of changes in activity as a function of auditory stimuli in different neuronal populations of a same nucleus that project to different targets. D‐MEMRI, combined with other MRI techniques, clearly harbors potential for unraveling seasonal, hormonal, pharmacological or even genetically driven changes in a neuronal circuit, by simultaneously measuring changes in morphology, activity and connectivity. Copyright © 2004 John Wiley & Sons, Ltd.
Interference with one‐trial appetitive and aversive learning by ether and ECS
Authors: Herz Michael J. 
Published: January 2005

AbstractStudies were undertaken to explore the effects of two amnesic agents upon appetitive and aversive learning in the same apparatus. Ss given electroconvulsive shock (ECS) within 80 sec or 15 min of punishing shock, and Ss administered ECS or ether 20 sec after the end of a 60‐sec water reinforcement period evidenced significant deficits on retention tests. The footshock‐ECS Ss showed significantly shorter latencies and greater activity than Ss given footshock alone. Conversely, Ss given water reinforcement and ECS had longer latencies and less activity than Ss given only water reinforcement. The results support the contention that postrial ECS and either disrupt perseverative neural processes representing appetitive as well as aversive learning and suggest the possibility that memory consolidation takes place at different rates for the two types of tasks.
L‐glutamate blockade of transmission at the giant synapse of the squid stellate ganglion
Authors: Kelly J. S. , Gage P. W. 
Published: January 2005

AbstractThe addition of L‐glutamate to the perfusion fluid of the squid stellate ganglion in concentrations from 5–100 mM led to a marked depression of the maximum rate of the rise of the PSP but never caused a detectable change in the membrane potential or conductance. In solutions containing 5 mM of glutamate, the reduction in the maximum rate of rise of the PSP occurred slowly and was incomplete after 60 min, however, in high concentrations the decline was much more rapid and the PSP disappeared completely. In glutamate free sea water the PSP rapidly reappeared and recovered its initial rate of rise in about 30 min. Since glutamate depression can be attributed to desensitization this result is consistent with the view that the transmitter substance is either glutamate or a chemically related compound. In the presence of 100–50 mM of magnesium the synapse is insensitive to 5 mM of glutamate and 10 mM is much less effective, perhaps as a result of magnesium glutamate binding. Thiosemicarbazide, an inhibitor of the enzyme system, glutamate decarboxylase, failed to cause an increase in the amplitude or duration of the PSP or an increase in potency of exogenous glutamate.
Effectiveness of temporal pattern in the input to a ganglion: Inhibition in the cardiac ganglion of spiny lobsters
Authors: Rao K. Pampapathi , Babu K. Sasira , Ishiko N. , Bullock Theodore H. 
Published: January 2005

Abstract(1) The single inhibitor axon of one side, going to the cardiac ganglion of Panulirus in a preparation with the central nervous system removed, was stimulated at a constant mean frequency but with different temporal fine structure. In particular, inhibitory trains with uniform intervals are compared with trains of alternately short and long intervals (“paired pulses”). Different ratios of short to long interval were used and, besides pairs, groups of up to 8 shocks. (2) Sixteen different measures of the inhibitory effect upon various aspects of the electroneurogram of the heart beat are compared. Some are more sensitive, others are more consistent. (3) Pattern sensitivity is found, that is the heart beat slows to different extents for different temporal structures. Trains of uniform intervals were generally more effective than any other pattern. Bursts of 7 or 8 are less effective than shorter bursts with the same minimum and mean interval. (4) The same burst has a different effect according to the phase of the heart cycle at which it arrives; the later the arrival the greater the effect. At the optimal phase and impulse interval, the minimum number of impulses for a just noticeable inhibitory effect (5–10%) is about 4. (5) In some preparations aging was associated with a reversal from inhibition to acceleration and such changes were not necessarily in parallel for different stimulus patterns. (6) On present evidence it cannot be said that the pattern sensitivity is explained by the effect of conditioning shock‐test shock interval on the synaptic response to the test shock. (7) Evidence does not yet permit evaluation of the possible role of pattern sensitivity under normal conditions. The significance at presetn is the finding that in a nearly ideal preparation for testing, a postsynaptic neuron can “read,” i.e., respond differently to the same mean frequency according to temporal fine structure.