bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of temporal dispersion on compound action potential area in human peripheral nerve
Authors: Olney Richard K. , Budingen Hans J. , Miller Robert G. 
Published: January 2005

AbstractIn 32 ulnar nerves of healthy volunteers, the mean area of the compound muscle action potential recorded over abductor digiti minimi was reduced by 7.4% when comparing above‐elbow with wrist stimulation and by 1.9% when comparing above‐elbow with below‐elbow stimulation. In 20 of these nerves, the mean area of the compound nerve action potential (CNAP) recorded over the fifth digit was reduced by 36% when comparing above‐elbow with wrist stimulation. Area reduction of the compound action potential, especially of the CNAP, appears to be a characteristic effect of temporal dispersion in peripheral nerve when utilizing the bipolar recording technique routinely employed in clinical neurophysiology. A thorough understanding of the effects caused by temporal dispersion and of their quantitative limits in normal peripheral nerve is important for the proper interpretation of nerve conduction studies.
Response to total body irradiation in dermatomyositis
Authors: Kelly John J. , Madoc‐Jones Hywel , Adelman Lester S. , Andres Patricia L. , Munsat Theodore L. 
Published: January 2005

AbstractThere were two patients with severe dermatomyositis refractory to immunosuppressive therapy treated with 150 rad of total body irradiation given over a period of 5 weeks. Both patients responded promptly with minimal side‐effects and remain in partial remission 42 and 18 months after completion of the treatment. Total body irradiation is effective in some patients with dermatomyositis who are refractory to standard therapy.
Expression of fiber type specific proteins during ontogeny of canine temporalis muscle
Authors: Shelton G. Diane , Cardinet George H. , Bandman Everett 
Published: January 2005

AbstractThe canine masticatory muscles contain a unique adult fiber type composition and different contractile protein isoforms than do adult limb muscles. To determine when these characteristic proteins are expressed during development, samples from canine temporalis (masticatory) and pectineus (limb) muscles were compared between 55 days gestation and 60 days postpartum by histochemical, biochemical, and immunocytochemical analysis. At 55 days gestation and 3 days postpartum, both muscles contained identical histochemical type 2C fibers, native myosin isozymes, and myosin light and heavy chains. By 14 days postpartum, fiber‐type expression in these muscles diverged, with resultant formation of type 1 and type 2M fibers in the temporalis muscle and type 1 and 2A fibers in the pectineus muscle. The distinctive myosin isoforms, light chains, and heavy chain of the temporalis muscle were also expressed 2 weeks postpartum. Based on the methods used in this study, we conclude that (1) the temporalis muscle develops from embryonic fibers that initially contain a myosin indistinguishable from embryonic limb muscle fibers, suggesting they have a common precursor, and (2) the myosin light chains and heavy chain unique to the temporalis muscle are initially expressed 2 weeks postpartum.
Adaptation of skeletal muscle to immobilization in a shortened position
Authors: Baker James H. , Matsumoto Dan E. 
Published: January 2005

AbstractThis study determined the morphological changes and adaptations that occur following immobilization of rat soleus and gastrocnemius muscles when the ankle joint is placed in complete plantar flexion for 2, 5, 7, 14, 21, and 28 days by means of plaster casts. Previous studies of such shortened muscles have shown that the number of sarcomeres in series is reduced, but how the sarcomeres are reduced has not been determined. We observed that the fibers in the midbelly region of the muscles demonstrated a progressive degenerative process over the first few weeks. Myofibrils across the entire width of the affected fibers underwent dissolution. However, by 4 weeks new myofibrils were being formed, and sarcomere lengths appeared normal. Portions of the fibers near the tendon underwent segmental necrosis. These findings are similar to the response of the soleus and gastrocnemius muscles to tenotomy and are clinically relevant to orthopedic procedures that maintain muscles in shortened conditions for prolonged periods.
Muscle imaging in neuromuscular disease using computerized real‐time sonography
Authors: Fischer Asma Q. , Carpenter Darrell W. , Hartlage Patricia L. , Carroll James E. , Stephens Sharon 
Published: January 2005

AbstractThe results of a study utilizing computerized real‐time sonography (CRS) to image muscles in patients with neuromuscular disease are presented for 67 patients, 37 with neuromuscular disease and 4 with upper motor neuron disease, and 26 age‐matched healthy controls between the ages of 2 days and 59 years. CRS is a safe, noninvasive, atraumatic method for evaluating a broad range of neuromuscular diseases. It is capable of differentiating myopathies or dystrophies from neurogenic atrophies and floppy infants with “central” hypotonia from those with neuromuscular diseases.
Spatial distribution of fiber types in skeletal muscle: Test for a random distribution
Authors: Venema Henk W. 
Published: January 2005

AbstractA statistical test is introduced for the assessment of fiber type grouping based on the number of neighboring fibers of different histochemical type. It is conceptually simple and can be applied to regular and irregular fiber patterns alike. One important feature of this test is that it has more power than existing ones, which means that deviations from a normal situation can be detected in an earlier stage than with any other method. The dependency of the outcome of the test on type‐specific size differences is rather small. Moreover, a method is given to correct for this bias. With the aid of the test it is shown that in normal muscle tissue of young persons a slight segregation of fiber type is a common situation.
Comparison of acoustic and electrical signals from erectores spinae muscles
Authors: Stokes Ian A. F. , Moffroid Mary S. , Rush Stanley , Haugh Larry D. 
Published: January 2005

AbstractComparison was made between simultaneous recordings of the electromyogram (EMG) and acoustic myogram (AMG) signals and the torque produced by the lumbar erectores spinae muscles of three healthy subjects while they performed isometric contractions. Repeatability of each signal was studied. The AMG had a relationship to the torque which was more quadratic than linear, whereas that of the EMG was more linear. The coefficient of variability of residuals about a „best‐fit”︁ line was 8.55% for torque‐increasing EMG recordings and 19.2% for torque‐increasing AMG recordings. At the same torque, the EMG was on average about 10% greater for increasing‐torque recordings than for decreasing‐torque parts of the recordings, but the magnitude of the AMG signal was about 10% less. With repeated testing on the same day, the coefficient of variability of the signal/torque relationship (torque‐increasing) was 9% for EMG and 23% for AMG signals. With long‐term testing over 2 weeks these coefficients were 23 and 39%, respectively. Correlation analysis showed that the two signal/torque relationships varied independently of each other.
Neurovascular‐anastomosed muscle grafts in rabbits: Functional deficits result from tendon repair
Authors: Guelinckx Paul J. , Faulkner John A. , Essig David A. 
Published: January 2005

AbstractIn rabbits, 9 g rectus femoris (RFM) muscles were grafted with tendon repair and with (1) nerves and blood vessels intact, (2) nerves intact and blood vessels anastomosed, or (3) nerves and blood vessels anastomosed. The influences of tendon, nerve, and vascular repair on the functional capabilities of grafts were compared 15–120 days after grafting. Data were collected on the mass, total protein content, oxidative capacity, maximum force development, and fatigability of grafts and control RFM muscles. When stabilized 90–120 days after grafting, mean values for the three types of grafts were not significantly different. Compared with values for control RFM muscles, each type of graft had significantly lower mean values for mass, total protein content, and maximum force, but the grafts were more resistant to fatigue. In RFM grafts, nerve and vascular repair do not contribute significantly to the impairments. Consequently, tendon repair appears to be responsible for the major functional deficits.
Spinal roots of rats poisoned with methylmercury: Physiology and pathology
Authors: Arimura K. , Murai Y. , Rosales R. L. , Izumo S. 
Published: January 2005

AbstractThe evoked potentials in the ventral and dorsal roots were recorded independently by stimulating the sciatic nerve of both control and methylmercury‐poisoned rats. Poisoned rats showed markedly decreased amplitudes but normal latencies of the potentials evoked in the dorsal roots. Potentials evoked in the ventral roots had normal latencies and amplitudes. Pathological correlates indicated acute axonal degeneration of the dorsal roots, with a significant decrease of the large and small myelinated fiber densities. The ventral roots were histologically unremarkable. Our pathological confirmation of the electrophysiologic changes in the methylmercury‐poisoned rats enables us to substantially assess the pathophysiological aspects of acute lesions in the spinal roots.
Small‐caliber skeletal muscle fibers do not suffer necrosis in mdx mouse dystrophy
Authors: Karpati George , Carpenter Stirling , Prescott Steven 
Published: January 2005

AbstractThe prevalence of internal nuclei in muscle fibers (centronucleation), which is a reliable cumulative index of all prior muscle fiber necrosis, was measured at different ages in different muscles of mdx mice and was correlated with muscle fiber diameter. The prevalence of centronucleated fibers (as percentage of total number of fibers) rose gradually after age 20 days until it reached a peak level of 80% at age 60 days. No significant centronucleation (or necrosis) was observed in the following circumstances: in 4 different limb muscles before age 15 days, in leg muscles that were denervated by peripheral nerve section or rendered immobile by high thoracic cordotomy at 15 days, or in rotator extraocular muscles throughout the animals' life span. In these situations, muscle fiber diameter remained below approximately 20 μm. The mechanism by which small‐diameter fibers are resistant to necrosis in mdx dystrophy is unknown, but a similar situation exists in hamster and Duchenne muscular dystrophy.
Serum CK, calcium, magnesium, and oxidative phosphorylation in mdx mouse muscular dystrophy
Authors: Glesby Marshall J. , Rosenmann Eduardo , Nylen Edward G. , Wrogemann Klaus 
Published: January 2005

AbstractSerum creatine kinase (CK) activity, calcium (Ca) and magnesium (Mg) contents of skeletal muscle and isolated mitochondria, as well as oxidative phosphorylation of X‐linked muscular dystrophic (mdx) mice were compared with normal control animals at ages 5, 10, and 23 weeks. Serum CK is elevated in mdx mice at all ages, with highest activities at 5 weeks. The Ca content of dystrophic skeletal muscle is increased at all ages, whereas no clearly abnormal trend in muscle Mg levels was observed. Noncollagen protein (NCP), which was used as a reference base, is significantly diminished in muscle from 10‐ and 23‐week‐old mdx animals. Isolated mitochondria from mdx mice have elevated calcium content and decreased respiratory control ratios with NAD‐linked substrates pyruvate/malate. The findings are distinct from those in dystrophic mice, strain 129/ReJ, but similar to observations in dystrophic hamsters and Duchenne muscular dystrophy and reflect the occurrence of overt muscle cell necrosis.
Single‐channel activity in sarcolemmal vesicles from human and other mammalian muscles
Authors: Burton F. , Dörstelmann Ursula , Hutter O. F. 
Published: January 2005

AbstractSegments of mammalian, including human, skeletal muscle 1–2 cm long can be induced to shed vesicles by treatment with collagenase in a high‐KCl solution containing no added calcium. The vesciles are encompassed by clean sarcolemma so that the gigaseal necessary for patch‐clamping is readily formed. The properties of inwardly rectifying potassium channels and of calcium‐activated potassium channels in patches detached form such vesicles are shown to be consistent with expectations based on earlier studies on intact muscle fibers and with patch clamp results on the same type of channels in other tissues. A cholride channel which rectifies outwardly with a conductance ranging from 15 to 50 pS is also described. The utility of sarcolemmal vesicles for the study of ion channels in human biopsy material is discussed.
Changes in skeletal muscle gene transcription induced by chronic stimulation
Authors: Brownson Carol , Isenberg Harvey , Brown Wendy , Salmons Stanley , Edwards Yvonne 
Published: January 2005

AbstractThe mRNA products of four genes, carbonic anhydrase III (CAIII), fast myosin heavy chain (MHCf), actin and glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH), were assayed by Northern and slot‐blot analysis in rabbit tibialis anterior and extensor digitorum longus muscles that were subjected to electrical stimulation for periods of up to 21 days. Marked changes in mRNA levels were seen for all four genes. The mRNA for CAIII, which is specific for type 1 fibers, rose significantly, whereas the MHCf mRNA fell markedly in the stimulated muscles. Changes in GAPDH mRNA were consistent with a reduced dependence on anaerobic glycolysis as an energy source. Actin mRNA levels were noticeably depressed in the early stages of stimulation. Thus for several classes of muscle protein, the response to chronic low‐frequency stimulation appears to involve changes at the level of gene transcription.
Stimulation SFEMG in myasthenia gravis
Authors: Jabre Joe F. , Chirico‐Post Jeannette , Weiner Mark 
Published: January 2005

AbstractThe diagnostic usefulness of single‐fiber electromyography (SFEMG) in the diagnosis of neuromuscular transmission disorders is well established. Increased jitter is one of the earliest indications of abnormality. In patients with severe weakness, tremor, or altered consciousness, performance of the study is difficult because of the degree of cooperation needed.We studied five patients and eight normal subjects with voluntary and stimulation SFEMG techniques. Our results, in search of normal values and changes with pathology, revealed differences in the values of jitter and the percentage of abnormal fibers between both techniques. The mean consecutive difference (MCD) is smaller (on average 30% less), and the percentage of abnormal fibers is lower (on average 10% less) with the stimulation technique. These differences are largely explained by the jitter measurement of one endplate with the stimulation technique versus two endplates with the voluntary. They may also be related, however, to the difference in motor unit populations sampled with each technique.
The effect of cholinesterase inhibitors on SFEMG in myasthenia gravis
Authors: Massey Janice M. , Sanders Donald B. , Howard James F. 
Published: January 2005

AbstractWe report four patients with myasthenia gravis (MG) in whom single‐fiber electromyography (SFEMG) jitter measurements were normal in some muscles while they were taking pyridostigmine and became abnormal 2–14 days after the medication was discontinued. When the abnormality of neuromuscular transmission in MG is mild, cholinesterase inhibitors may mask the findings of increased jitter on SFEMG.
Relationship of manual muscle testing to objective strength measurements
Authors: Aitkens Susan , Lord Janet , Bernauer Edmund , Fowler William M. , Lieberman James S. , Berck Peter 
Published: January 2005

AbstractThis study investigates the relationship between manual muscle test scores (MMT) and quantitative isometric strength measurements (QIS). It also evaluates the implications of that relationship for design of therapeutic trials. Extension and flexion strength at the elbows, hips, and knees of 21 neuromuscular disease patients were tested a total of 26 times utilizing both MMT and QIS testing. Paired data were evaluated with Spearman ranked correlation coefficients, and then QIS was predicted from MMT using Lowess, a consistent form of nonparametric regression. Finally, the implications of the Lowess analysis for designing a therapeutic trial were evaluated.MMT and QIS measurements were significantly correlated in all movements tested. Lowess analysis yielded prediction errors ranging from 16 to 24% of QIS range. Analysis of the sample size needed for a therapeutic trial suggested that a protocol measuring MMT would require more subjects for the same level of statistical significance as a protocol measuring QIS. Since it was not possible to reliably predict QIS values from MMT scores, such conversions are not appropriate for clinical use. This inconsistent relationship between MMT and QIS carries major implications for the design of therapeutic trials. Since therapeutic trials are time consuming, expensive, and most centers do not have large numbers of individuals available, using QIS as an outcome measure is a preferable research design.
Simulation of myopathic motor unit action potentials
Authors: Nandedkar Sanjeev D. , Sanders Donald B. 
Published: January 2005

AbstractNormal motor units (MUs) were simulated and their architecture altered to simulate the changes produced by myopathy. The concentric needle electromyographic recordings of motor unit action potentials (MUAPs) from the MUs were then also simulated. These simulated MUAPs showed features that are seen in myopathy: normal amplitude and slightly reduced area, MUAPs with simple waveform and reduced duration, and complex MUAPs with normal or increased duration. The MUAP waveforms were complex because of increased variability of fiber diameter and not because of loss of muscle fibers. The MUAP duration increased when the variability of fiber diameter increased. Finally, MUAPs similar to those seen in neurogenic diseases were produced from MUs in which the only abnormality was increased variability of fiber diameter.
Caffeine sensitivity of sarcoplasmic reticulum of fast and slow fibers from normal and malignant hyperthermia human muscle
Authors: Salviati Giovanni , Betto Romeo , Ceoldo Stefania , Tegazzin Vincenzo , Puppa Andrea Della 
Published: January 2005

AbstractWe have carried out a comparative study of caffeine sensitivity of the sarcoplasmic reticulum (SR) of fast and slow normal human fibers chemically skinned. Human slow‐fiber SR is more sensitive to caffeine than fast fiber SR; however, it releases less calcium and at a lower rate than the SR of fast fibers when exposed to threshold concentrations of caffeine. These results indicate that the SR calcium release mechanisms of SR of fast and slow human fibers are homologous but not identical. An increased sensitivity of SR to caffeine is found in both fast and slow fibers from human malignant hyperthermia muscle. However, fast fibers seem to be the most affected, since their caffeine threshold for contraction is very close to that of slow fibers.
Carpal tunnel syndrome in Lyme borreliosis
Authors: Halperin John J. , Volkman David J. , Luft Benjamin J. , Dattwyler Raymond J. 
Published: January 2005

AbstractNeurophysiologic evidence of median nerve entrapment in the carpal tunnel was present in 25% of patients with late Lyme borreliosis. Sixty‐eight of 76 consecutive, prospectively studied patients with late Lyme underwent neurophysiologic testing. Nineteen reported intermittent hand paresthesias; 17 had neurophysiologically confirmed carpal tunnel syndrome. This was not consistently associated with clinically apparent wrist arthritis or with neurophysiologically evident peripheral neuropathy. We conclude that a significant proportion of patients with late Lyme borreliosis develop carpal tunnel syndrome.
Comparison of sympathetic skin response with quantitative sudomotor axon reflex test in diabetic neuropathy
Authors: Maselli Ricardo A. , Jaspan Jonathan B. , Soliven Betty C. , Green Andrew J. , Spire Jean‐Paul , Arnason Barry G. W. 
Published: January 2005

AbstractThe sympathetic skin response (SSR), the quantitative sudomotor axon reflex test (Q‐SART), and cardiac beat‐to‐beat variability with respiration as measured by the expiratory/inspiratory ratio (E/I ratio) were studied in 39 patients with diabetic neuropathy of whom 33 also had one or more symptoms of autonomic involvement. In the lower extremities 87% of the patients with an absent SSR had an abnormal Q‐SART (P < 0.001), and 81% of patients with the SSR present had a normal Q‐SART (P < 0.02). The E/I ratio was abnormal in all but one of 23 patients with an absent SSR in the foot, and a normal E/I ratio was present only in those patients (n = 7) with the SSR present in hand and foot, and in an eighth patient who had SSR absent in the foot and present in the hand. A similar correlation was found between the E/I ratio and the Q‐SART in the foot, although 4 of 25 patients with an abnormal foot Q‐SART had a normal E/I ratio. We conclude that the concordance of results of the SSR and Q‐SART supports the combined use of these tests to uncover early distal sympathetic failure in diabetic neuropathy.
The spectrum of changes on 20 nerve biopsies in patients with HIV infection
Authors: Chaunu Marie‐Pierre , Ratinahirana Herilavitra , Raphael Martine , Hénin Dominique , Leport Catherine , Brun‐Vezinet Francoise , Léger Jean‐Marc , Brunet Pascal , Hauw Jean‐Jacques 
Published: January 2005

AbstractNerve and muscle blopsies were performed on 20 patients with HIV infection and peripheral neuropathy. Nine patients had distal symmetrical peripheral neuropathy (DSPN) (six ARC and three AIDS), six had inflammatory demyelinating polyneuropathy (IDP) (three ARC, one AIDS, and two otherwise asymptomatic patients), one had mononeuropathy multiplex (MM) (AIDS), 1 had mononeuropathy (ARC), one had meningoradiculitis (AIDS), and two had areflexia‐associated lymphocytic meningitides (ARC). DSPN exhibited axonal degeneration in four of nine cases and was associated with segmental demyelination in five of nine cases. IDP exhibited segmental demyelination associated with axonal degeneration in four of six cases. Demyelination was more frequent in asymptomatic patients (2 of 2 cases) and in ARC (7 of 12 cases), whereas axonal degeneration was predominant in AIDS (6 of 6 cases). Mononuclear cell infiltration was seen in 1 of 2 asympatomatic patients and in 11 of 12 ARC patients but was exceptionally found in AIDS (1 of 6 cases). Involvement of the walls of small vessels, mostly venules (“subacute microvasculitis”), was found in 1 of 2 asymptomatic patients, in 8 of 12 ARC patients, and never in AIDS. The polyclonal mononuclear cell population was composed mainly of Leu 2 (TB) positive cells in seven cases of ARC. No virions were seen in electron microscopy. HIV was isolated in two cases from the CSF or the nerve biopsy.