bluuebunny/crossref_metadata_2025_split huggingface dataset:
Becker muscular dystrophy recombinant DNA studies in identical twins
Authors: Ionasescu Victor , Ionasescu Rebecca , Searby Charles , Burns Trudy 
Published: January 2005

AbstractTwo identical twins with becker Muscular Dystrophy are reported. Both twins had the same red cell types for ABO, Rh, CDE, MNSs, Kelly, Lewis, Duffy, and Kidd. HLA typing detected the same antigens in both twins: A1, A26, B8, B17, DR3, DR7. Family history was negative. The twin patients showed identical haplotypes that were different from the haplotypes of the normal male members of the family. The sister of the twins showed a recombinant X chromosome. The informative haplotype with respect to the gene of BMD, present in the twins, was ascertained in their mother as well. Our findings strongly suggest that a mutation has occurred either in the mother or in the twins.
New concepts of the reinnervated motor unit revealed by vaccine‐associated poliomyelitis
Authors: Wiechers David O. 
Published: January 2005

AbstractA late onset of slowly progressive muscle weakness 30–40 years after acute polio is well known. Previous studies by the author and others have demonstrated transmission abnormalities within the reinnervated motor unit. These transmission abnormalities shown by motor unit action potential (MUAP) instability in size and shape with repetitive discharges occurs in postpolio patients who are and who are not complaining of progressive muscle weakness. Although some reinnervated MUAPs do seem to stabilize their neuromuscular transmission with time in mildly affected muscles, the question arises as to whether or not some MUAPs ever stabilize after polio. Two cases of acute polio personally followed by the author, one over a 9 1/2 year period, are presented. In both cases, in muscles where there are more deinnervated muscle fibers than could possibly be reinnervated, the MUAPs have remained unstable. New concepts of function in the reinnervated motor unit following polio are presented.
A clinical neurophysiologic study of tropical spastic paraparesis
Authors: Ludolph Albert C. , Hugon Jacques , Román Gustavo C. , Spencer Peter S. , Schoenberg Bruce S. 
Published: January 2005

AbstractDuring a field study in the Seychelles Islands, 19 patients with tropical spastic paraparesis (TSP) were evaluated electrophysiologically. Methods of assessment included motor and sensory nerve conduction studies, electromyography, and analysis of the somatosensory evoked potentials after stimulation of the tibial and median nerves. The results showed that the most prominent feature of the disease, a spastic paraparesis, is accompanied by subclinical involvement of spinal sensory pathways and a comparatively minor peripheral sensorimotor polyneuropathy.
False positive electrodiagnostic tests in carpal tunnel syndrome
Authors: Redmond M. David , Rivner Michael H. 
Published: January 2005

AbstractOf 50 normal subjects, 23 (46%) had at least one false positive electrodiagnostic test for carpal tunnel syndrome (CTS). There were 30% of the subjects who exhibited an abnormal median to ulnar sensory amplitude ratio of less than 1.1. In 7 subjects 8 extremities (14%) revealed prolonged residual latencies, and 4 extremities in 4 subjects (8%) had a difference of 0.4 msec between the median and ulnar palmar sensory latencies. The results of this study indicate that certain reported criteria for CTS are abnormal in a high percentage of normal subjects, thereby making them of limited value in the diagnosis of CTS. Of all the criteria studied, it appears that the comparison of the median to ulnar sensory latency across the carpal tunnel is of greatest potential value. However, even here a more conservative difference of 0.5 msec between median and ulnar nerves must be used to avoid false positive tests for CTS.
Jitter correction: A computer algorithm for reduction of the velocity recovery function artifact
Authors: Davis Graham R. , Ingram David A. , Fincham William F. , Swash Michael , Schwartz Martin S. 
Published: January 2005

AbstractThe measurement of neuromuscular jitter in single fiber electromyography may be artifactually raised by a component of interdischarge interval (IDI)‐dependent jitter caused by the velocity recovery function (VRF) in muscle fibers. We have developed a computer algorithm for on‐line mathematical correction for this artifact, thus improving the reliability of neuromuscular jitter estimates. The method, based on a modeling technique, was validated using intramuscular stimulation in order to either exclude an IDI‐dependent component (using regular stimulation) or to include an IDI‐dependent component (using pseudorandom stimulation). In 10 normal subjects the distribution of 106 corrected jitter values obtained using voluntary activity showed no difference from the measured values. This finding implies that previously published values for normal jitter are not likely to have been influenced by the VRF effect.
Effects of glycerol injection into rat sciatic nerve
Authors: Vallat J. M. , Leboutet M. J. , Loubet A. , Hugon J. , Moreau J. J. 
Published: January 2005

AbstractIn recent years, injection of pure glycerol into the trigeminal cistern has been used for the treatment of trigeminal neuralgia. The mechanism of action of this therapy remains unclear. Using both light and electron microscopy, we investigated the effects of microinjections of sterile, pure glycerol into the endoneurium of the sciatic nerve of the rat. We observed total destruction of both myelinated and unmyelinated fibers. In nearly all animals, signs of automutilation were observed in the paralyzed limb. Histological evidence of nerve degeneration appeared soon after injection, with intense proliferation of perineurial cells that eventually divided the endoneurium into numerous microcompartments.
Orthodromic study of the sensory fibers innervating the fourth finger
Authors: Valls Jose , Llanas Jose M. 
Published: January 2005

AbstractFourth finger stimulation has been used to obtain the compound nerve action potential (CNAP) of the median and ulnar nerves by a single cutaneous bipolar recording electrode placed in some specific sites of the upper limb. In normal subjects, the response was a combination of both action potentials which could be seen as separated peaks only when the recording was made at midarm with the elbow flexed at 90°. This finding is mainly attributed to the longitudinal sliding of nerves according to the joint movements. In patients with a carpal tunnel syndrome, there were a striking separation between the responses of both nerves in wrist recording. This finding allows this technique to be applied in the clinical inspection of median nerve entrapment at wrist, demonstrating graphically the delay on the median nerve action potential with regard to that of the ulnar nerve.
The Ca2+ ATPase content of slow and fast twitch fibers of guinea pig
Authors: Ferguson Donald G. , Franzini‐Armstrong Clara 
Published: January 2005

AbstractThe Ca ATPase content in the sarcoplasmic reticulum (SR) of fast and slow twitch skeletal fibers was estimated using two well‐characterized muscles of the guinea pig: the white bundle of the vastus lateralis and the soleus. Ca ATPase surface density was determined by counting the projections of individual molecules revealed on the cytoplasmic surface of freeze‐dried, rotary‐shadowed microsomal vesicles isolated from the two muscles. The Ca ATPase densities were 32,000/μm2 and 25,000/μm2 for the vastus lateralis and soleus muscles, respectively. The percentage of membrane area occupied by Ca ATPase‐free lipid patches was estimated using freeze‐fractured, rotary‐shadowed in situ SR. In soleus muscle the free SR of terminal cisternae and the longitudinal SR have 34.5 and 19.7% of their surface free of ATPase, respectively. In the white vastus less than 1% of the surface was not occupied by Ca ATPase. These values were combined with stereological data from the literature to give a ratio of total Ca ATPase content per unit fiber volume of 1:2, slow versus fast. This is considerably less than the approximately sixfold difference in the overall relaxation time and the half times to relaxation between the two fiber types. This suggests that other factors such as differences in enzyme kinetics or cytoplasmic Ca buffering proteins must also play a role in determining rate of relaxation.
Reinnervation of sweat glands in the mouse: Axonal regeneration versus collateral sprouting
Authors: Kennedy William R. , Navarro Xavier , Kamal Hiroyuki 
Published: January 2005

AbstractThe capacity of sudomotor axons to reinnervate sweat glands by regeneration after freezing was compared with their capacity to reinnervate by the mechanism of collateral sprouting. Two groups of mice were prepared in the same manner, with a single exception. All nerves to the hind paw were cut and tied to prevent regrowth. The exception, the lateral plantar nerve, was left intact in one group and frozen at the ankle in the other group. Reinnervation of sweat glands in the paw was charted frequently for 10 weeks using a silastic mold method. We found that sudomotor axons regenerating from the frozen nerve functionally reinnervated sweat glands of the paw sooner, beginning at 15 days postoperation, and at a higher rate than reinnervation from the collateral branching intact nerve, that began at about 25 days. Full recovery occurred by 41 days in most animals of both groups. We also found that stimulation of sweating by pilocarpine activated more sweat glands during the reinnervation period than stimulation by heating the mice, suggesting that the newly regenerating sudomotor axons have a high threshold.
Carnitine stimulation of pyruvate dehydrogenase complex (PDHC) in isolated human skeletal muscle mitochondria
Authors: Uziel Graziella , Garavaglia Barbara , Di Donato Stefano 
Published: January 2005

AbstractL‐carnitine stimulated CO2 production from 1‐14C pyruvate in mitochondria from human skeletal muscle nearly twofold. A comparable increase in the pyruvate dehydrogenase complex (PDHC) activity was seen. Moreover, in the presence of L‐carnitine and at pyruvate concentration greater than 0.25 mM, this effect was associated with a marked increase of acetylcarnitine synthesis. Deoxycarnitine, an inhibitor of carnitine acetyltransfersase (CAT), partially reversed the effect of carnitine on PDHC activity. The stimulatory effect of carnitine on PDHC activity in human mitochondria is mediated by the modulation of the intramitochondrial acetylCoA/CoASH ratio.
Conduction studies in peripheral cat nerve using implanted electrodes: I. Methods and findings in controls
Authors: Christian Krarup , Loeb Gerald E. 
Published: January 2005

AbstractSilicone rubber cuff and patch electrodes with multiple contacts were implanted along the sciatic‐tibial‐plantar nerves in cat for repeated studies of conduction properties of normal peripheral nerve over periods of time. The contacts were used in various combinations for precise localization of changes in conduction velocities and excitability along the extent of normal nerves. In this paper the particular characteristics and limitations associated with cuff‐electrode recordings of neural activity are discussed. The nerve action potential was recorded using a tripolar configuration with a central lead flanked by two shunted leads at symmetrical distances. This configuration records the spatial derivative of the action potential and rejects potentials from sources outside the cuff. The voltage changes are restricted by the silicone cuff, and the dynamic range is therefore very high, allowing detection from single myelinated fibers to whole nerve responses. The electrodes are well suited for following the development of regeneration and degeneration following experimental lesions.
Changes in center of gravity in boys with duchenne muscular dystrophy
Authors: Barrett Ruth , Hyde Sylvia A. , Scott Oona M. , Dubowitz Victor 
Published: January 2005

AbstractA study was undertaken, using methods of stabilometry to compare stability of stance in normal children (n = 37) and those with Duchenne muscular dystrophy (n = 61). The purpose of this study was to monitor changes in the locus of the center of gravity and the range and frequency of sway and to evaluate the effect of orthotic application in an attempt to obtain information that would assist further development of orthoses.In group 1, boys with Duchenne muscular dystrophy who were still walking without assistance (mean age 7.2 ± 1.76 years), the analysis of sway showed that, between 5 and 6 years of age, the boys already had ranges of anteroposterior (A/P) and lateral (Lat) sway that were significantly greater than those found in normal children (A/P P < 0.05, Lat P < 0.01). In group 2, boys with Duchenne muscular dystrophy when orthoses had been introduced (n = 23, mean age 10.4 ± 1.47 years), the center of gravity was returned to a more normal position. There was a reduction of the antero‐posterior range of sway, but the lateral range of sway remained significantly greater (P < 0.01) as did the frequency of sway in both the anteroposterior and lateral directions (A/P P < 0.001, Lat P < 0.001).
Longitudinal conduction studies in hereditary motor and sensory neuropathy type 1
Authors: Roy E. Pierre , Gutmann Ludwig , Riggs Jack E. 
Published: January 2005

AbstractMotor conduction studies were performed serially in 10 patients, ages 10–62 years, with clinical and electrophysiological criteria of hereditary motor and sensory neuropathy type 1 (HMSN‐1) over periods of 11–19 years. Median nerve conduction velocity (MNCV) and distal motor latency showed no significant change on serial studies. Mean median compound muscle action potential (CMAP) amplitude values, however, decreased 66% in 8 patients. Observed clinical progression in HMSN‐1, over prolonged periods of time, was not associated with MNCV slowing. However, CMAP amplitude reduction, reflecting progressive axonal loss, correlated with clinical deterioration.
Proportions and sizes of muscle fiber types in the hamster diaphragm
Authors: Reid W. Darlene , Hards Jennifer M. , Wiggs Barry R. , Wood Elizabeth N. , Wright Peggy V. , Pardy Richard L. 
Published: January 2005

AbstractThis study demonstrated that there was interanimal and interregional variability of proportions and sizes of the muscle fiber types in the hamster diaphragm. Muscle fiber type proportions and sizes were determined for each side (right, left), surface (abdominal, thoracic), and region (sternal, anterior costal, posterior costal, crural) in six hamsters. There was marked regional and surface‐to‐surface variability and some interanimal variability in proportions and sizes of fiber type within the hamster diaphragm. The sternal and costal regions were relatively homogeneous. However, there were differences in both proportions and sizes of fiber types between the thoracic surface of the crural region and the abdominal surface of the crural region. These two surfaces of the crural region differed from the rest of the diaphragm. For muscle fiber type proportions, type 2a fibers demonstrated the most interanimal variability. Muscle fiber size varied little between animals.
Internalized myofiber capillaries: Observations on their origin and clinical features
Authors: Gutmann Ludwig , Wolf Robert , Nix Wilfred , Goebel Hans H. , Schochet Sydney S. , Hopf Hanns C. , Kramer Günter 
Published: January 2005

AbstractInternalized capillaries limited to type 1 muscle fibers were noted in seven patients. They occurred in each case in association with a similar admixture of neurogenic and myopathic features that included atrophic and hypertrophic fibers, internal nuclei, fiber splitting, and endomyseal and perimyseal fibrosis. Internalized capillaries in enlarged type 1 fibers arose from fiber splits on step section study of four patients. They occurred in the gastrocnemius, quadriceps, and soleus muscles from patients with a variety of disorders that included Becker dystrophy, diabetes mellitus and strenuous leg activities, Achilles tendon rupture, and myotonic dystrophy. Exercise‐induced myalgias were noted in the four patients with most plentiful intramuscular capillaries, and in three of these muscle hypertrophy was present. The concurrence of internalized myofiber capillaries and exercise induced myalgias may represent an associated biochemical/pathological defect.
Sural nerve biopsy in chronic inflammatory demyelinating polyradiculoneuropathy
Authors: Krendel David A. , Parks Helen P. , Anthony D. Carter , St. Clair Mary Beth , Graham Doyle G. 
Published: January 2005

AbstractWe compared histologic features of sural nerve biopsies in 14 patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) with those in other forms of neuropathy. In CIDP endoneurial pericapillary cellular infiltrates were found in 4 patients (29%), onion bulbs in 5 patients (36%), and predominant demyelination in 7 patients (50%). None of these abnormalities was specific, but cellular infiltrates and onion bulbs appear to be diagnostically useful when combined with clinical information. To detect macrophage infiltration of myelin, cell nuclei were counter‐stained in 20 teased fiber preparations. Nine patients with CIDP had a significantly higher mean number of cells per centimeter of teased fiber than 11 patients with other neuropathies. Despite overlap, significant infiltration of myelin detected by this method suggests CIDP in an appropriate clinical setting.
Diazepam improves recording of lumbar and neck somatosensory evoked potentials
Authors: Pfeiffer Frederick E. , Peterson LaVonne , Daube Jasper R. 
Published: January 2005

AbstractTo determine whether the decrease in muscle artifact provided by diazepam is of sufficient clinical value to justify its use, somatosensory evoked potentials recorded in examinations of 73 consecutive patients were compared with those recorded from 33 subsequent patients who were given 10 mg of diazepam orally just before the examination. With diazepam pretreatment there was clear improvement in the quality of lumbar and neck recordings—increased reproducibility and definition and ease of measurement— and also greater tolerance of the procedure and a slight shortening of time required for the test.
Effects of different sensory inputs on the median‐derived somatosensory evoked potential
Authors: Reisin Ricardo C. , Goodin Douglas S. , Aminoff Michael J. , Mantle Mary M. 
Published: January 2005

AbstractWe studied the effect of a variety of “interfering” stimuli on the median‐derived somatosensory evoked potentials recorded over Erb's point, cervical spine, and scalp. We found that the amplitude of N20 and P27 recorded over the scalp was attenuated by active movement, vibration, and tactile stimulation of the ipsilateral hand but not by passive movement. Cervical and peripheral responses were unaffected. The pathophysiologic basic and clinical significance of these findings are discussed.
Preferential activation of muscle fibers with peripheral magnetic stimulation of the limb
Authors: Lotz Barend P. , Dunne John W. , Daube Jasper R. 
Published: January 2005

AbstractMagnetic and electric activation of limb nerve and muscle were compared in normal subjects of different age, gender, and habitus. Direct stimulation of nerve and muscle showed that activation of intramuscular nerve fibers in the arm and leg occurs at a lower threshold for magnetic stimulation than for electric stimulation. Sensory nerve fibers had a lower threshold with electric stimulation. Muscle activation and stimulus artifact with magnetic stimulation precluded reliable recording of distal sensory nerve action potential in all subjects.
Survival prediction in amyotrophic lateral sclerosis
Authors: Jablecki Charles K. , Berry Charles , Leach Judy 
Published: January 2005

AbstractThis longitudinal study of 194 patients with sporadic ALS demonstrated that it is possible for physicians to predict the approximate survival time for an individual ALS patient given: (1) the age of the patient, (2) the duration of his weakness and (3) an estimate of his clinical disability (ALS Score). This information is of value in the clinical management of ALS patients, and it should facilitate construction of experimental therapeutic trials in ALS.
Dystrophin distribution in heterozygote mdx mice
Authors: Watkins Simon C. , Hoffman P. , Slayter Henry S. , Kunkel Louis M. 
Published: January 2005

AbstractThe distribution of dystrophin in myofibers from normal, mdx hemizygous, and mdx heterozygous mice was studied at various times in development. While normal mice exhibit dystrophin immunostaining around the entire fiber periphery regardless of age, mdx hemizygous mice exhibit no staining (0–35 days). In contrast, young (10 day) heterozygous mdx mice showed neighboring dystrophin‐negative and dystrophin‐positive fibers as well as fibers with a discontinuous or patchy dystrophin labelling. Older heterozygotes displayed very few negative fibers, with most fibers exhibiting apparently complete dystrophin immunostaining. This, coupled with the absence of muscle fiber degeneration at any age point, and the apparently normal levels of dystrophin in older heterozygous mice, indicates that myonuclei containing the dystrophin gene can compensate for myonuclei which do not contain the dystrophin gene within the same myofiber.
Muscle fatigue in some neurological disorders
Authors: Lenman Andrew J. R. , Tulley Francis M. , Vrbova Gerta , Dimitrijevic Milan R. , Towle Josie A. 
Published: January 2005

AbstractFatigue of tibialis anterior (TA) was induced by repetitive electrical stimulation. Using this test, patients with upper motor neuron muscle weakness owing to multiple sclerosis (MS) and injuries to the spinal cord showed greater fatigability of their TA muscles, suggesting that the muscle fiber population changed toward that typical of fatigable motor units. During repetitive stimulation, in addition to the decrement in tension there was an increase in half‐relaxation time of tetanic contractions at 40 Hz in both subjects and patients. The increase in half relaxation during repeated activity was greater in patients with MS and spinal cord injury than in healthy subjects, suggesting that the long‐term inactivity affected the efficiency of the Ca2+ uptake mechanism of their muscle fibers. Thus long‐term inactivity of patients with upper motoneuron dysfunction leads to increased fatigability of their muscles and exaggerates the slowing of muscle relaxation after prolonged exercise.
Electrophysiologic evaluation of spinal cord motor conduction
Authors: Berger Alan R. , Shahani Bhagwan T. 
Published: January 2005

AbstractSpinal cord motor conduction was determined by stimulating with a monopolar needle at the C5 cord level and recording evoked motor potentials from the ipsilateral tibialis anterior muscle. Minimal F wave and direct motor latencies from the peroneal nerve were used to calculate peripheral conduction time. Mean velocity index (defined as the distance from C5 to L4 divided by central conduction time) of 15 normal subjects was 64.9 m/sec (SD 7.5). In 5 patients with multiple sclerosis the mean velocity index was 40.6 m/sec (SD 6.5), whereas in 3 patients with cervical myelopathies, due to extradural compression, the mean velocity index was 32.8 m/sec. A repeat study in one of the latter patients, 4 days after removal of a C5 disc, documented a marked improvement in cord conduction. In a patient with a thoracic and cervical syrinx, cervical cord stimulation on the clinically affected side failed to evoke a motor potential, whereas the unaffected side was normal. This method provides a simple and effective way to evaluate spinal cord motor conduction using routine electrodiagnostic equipment.