bluuebunny/crossref_metadata_2025_split huggingface dataset:
Resistance to ischemic conduction block of the peripheral nerve in hyperglycemic rats: An electrophysiological study
Authors: Shirabe Susumu , Kinoshita Ikuo , Matsuo Hidenori , Takashima Hidetoshi , Nakamura Tatsufumi , Tsujihata Mitsuhiro , Nagataki Shigenobu 
Published: January 2005

AbstractResistance to ischemic conduction block (RICB) was studied in rats with streptozotocin (STZ) induced hyperglycemia, hyperglycemia by glucose injection, and glycerin‐induced hyperosmolarity. Ischemia was produced by tight ligation at the base of the tail. The time required for nerve action potentials (NAP) to disappear was defined as the disappearance time of NAP (DT‐NAP). Both STZ and glucose rats showed a marked prolongation of DT‐NAP at 2 hours after injection of STZ (up to 120 minutes) or glucose (up to 95 minutes), as compared with the control rats (less than 45 minutes). Hyperosmolar rats showed no prolongation of DT‐NAP. The amplitude of NAP remained at the initial level for at least 2 hours after ligation of the sciatic nerve, whereas NAP disappeared within 45 minutes after ligation of the abdominal aorta. These findings indicate that the RICB can be produced by means of hyperglycemia without the presence of diabetic neuropathy and is the most sensitive indicator of hyperglycemia.
Muscle action potential propagation velocity changes during activity
Authors: Juel Carsten 
Published: January 2005

AbstractFatigue from high frequency stimulation is associated with EMG signal changes, which are primarily due to a slowing of the sarcolemma conduction velocity. In the present study, in which isolated mouse soleus and extensor digitorum longus muscles have been studied, it is shown that the action potential propagation velocity is (1) decreased by an increased extracellular potassium concentration, (2) independent of extracellular pH, (3) decreased by low intracellular pH, and (4) nearly independent of moderate changes in the sodium gradient. The EDL muscle is more affected than the soleus muscle. The ion effects on propagation velocity are seen within the physiological ranges. The propagation velocity was decreased after 2 min of electrical stimulation and recovered with a time course similar to the pH recovery. The effects of extracellular potassium and internal pH are due to independent mechanisms.
Role of glucocorticoids in increased muscle glutamine production in starvation
Authors: Tischler Marc E. , Henriksen Erik J. , Cook Paul H. 
Published: January 2005

AbstractThe influence of glucocorticoids on muscle glutamine production in starvation was studied by using cortisol‐treated or non‐cortisol‐treated, starved, adrenalectomized rats. Administration of cortisol at physiological doses in vivo (1 mg/100 g body weight) to fasted, adrenalectomized rats increased the muscle ratio of glutamine/glutamate and the activity of glutamine synthetase after only 6 hours. Prior treatment of fasted, adrenalectomized animals with actinomycin D or proglavine abolished these increases by cortisol. Therefore, cortisol induces muscle glutamine synthetase, and this induction can be detected by changes in the fresh‐muscle ratio of glutamine/glutamate. Using this ratio as a qualitative indicator of muscle glutamine synthesis, the role of glucocorticoids in modifying muscle glutamine production in starvation was studied. In fresh‐frozen soleus, extensor digitorum longus, and diaphragm muscle, starvation led to greater ratios of glutamine/glutamate and higher levels of tyrosine, which are indicative of enhanced muscle protein turnover. These effects were not apparent in starved, adrenalectomized animals but were restored, at least partially, by administering a physiological dose of cortisol. Therefore, glucocorticoids seem essential for promoting muscle glutamine production in starvation probably by inducing the activity of glutamine synthetase.
AAEE minimonograph #29: Automatic quantitative electromyography
Authors: Dorfman Leslie J. , McGill Kevin C. 
Published: January 2005

AbstractThe present status of different computerized methods of automatic quantitative electromyography are reviewed. Interference pattern methods–turns analysis, spectral analysis–are efficient, but the results usually cannot be directly related to the physiological properties of the motor units. Integration analysis does not currently have a major role in diagnostic electromyography. Traditional measurement of single motor unit action potentials during weak contraction can be facilitated and made more objective with computer assistance, but only the lowest‐threshold motor units in the muscle are amenable to study. A new class of methodologies under development permit the decomposition of interference patterns into their constituent motor unit action potentials for measurement of configurational and behavioral properites. Patient data from these various methods can be statistically compared with normative data bases available on‐line in computerized electromyographs. Both qualitative and quantitative electromyography have applications in the neuromuscular electrodiagnostic examination.
AAEE case report #15: Ulnar neuropathy at or distal to the wrist
Authors: Olney Richard K. , Hanson Maurice 
Published: January 2005

AbstractA 56‐year‐old woman developed insidiously progressive, painless weakness of her left hand. Clinical and electrodiagnostic abnormalities were limited to the motor function of the hand, with the hypothenar less affected than more distal ulnar muscles. Compression of the distal ulnar nerve by a ganglionic cyst was surgically relieved and there was postoperative improvement. The electrodiagnosis of ulnar neuropathy at or distal to the wrist is reviewed together with relevant anatomic and clinical aspects of these uncommon lesions.
Physiologic and anatomic basis for contralateral R1 in blink reflex
Authors: Soliven Betty , Meer Jacob , Uncini Antonino , Petajan Jack , Lovelace Robert 
Published: January 2005

AbstractWe studied the rate of appearance and mechanism of contralateral R1 responses in normal subjects. Contralateral R1 could be produced by facilitating maneuvers such as a gentle contraction of the orbicularis oculi and conditioning stimulus of the median nerve. In addition, changing the position of the stimulating anode to the midline evoked these responses that were abolished by blocking the contralateral supraorbital nerve, confirming its peperipheral origin. We conclude that crossed trigeminofacial pathways probably exist in normal subjects, but in some instances contralateral peripheral trigeminal ophthalmic sensory fibers may be stimulated, giving rise to a contralateral R1 response.
The spectrum of peripheral neuropathy associated with ARC and AIDS
Authors: Miller Robert G. , Parry Gareth J. , Pfaeffl Wolfgang , Lang William , Lippert Randolph , Kiprov Dobri 
Published: January 2005

AbstractPeripheral neuropathy is increasingly recognized as a complication of the Aquired Immune Deficiency Syndrome (AIDS) and AIDS‐related complex (ARC), but the varied clinical features have been incompletely described. Thirty homosexual men with peripheral neuropathy were evaluated in this study. Twenty‐one had ARC and nine had AIDS. Four distinct clinical syndromes were recognized: distal sensorimotor polyneuropathy, chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), mononeuropathy multiplex, and progressive polyradiculopathy. Four patients with clinical, electrophysiologic, and histologic evidence of CIDP and severe progressive weakness improved with plasma exchange, three regaining normal function.
Myosin ATPase intermediate density fibers for diagnosis of reinnervation
Authors: Griffin Joe L. , Pezeshkpour Gholam H. 
Published: January 2005

AbstractMyosin ATPase (pH 9.4) differentiates two muscle fiber types in healthy human muscle, while diseased muscle often contains intermediate density fibers (IDFs). We evaluated the possibility that, since almost all IDFs in pathologic muscle biopsies are changing type after reinnervation by a motor axon of the opposite type, IDFs are useful in diagnosis. In a retrospective study of 208 muscle biopsies, IDFs were seen as often as were esterase‐positive angular atrophic fibers (EPAAFs). In denervation identified by EMG and by histopathology, EPAAFs and IDFs were found much more often than were other indicators. Of biopsies diagnosed without use of IDFs as minimal histologic change or no pathologic diagnosis, 16% had IDFs with sparse EPAAFs and 21% had IDFs without EPAAFs, suggesting mild denervation with rapid reinnervation. IDFs correlate well with EPAAFs, identifying reinnervated versus denervated fibers. Type grouping reveals completed reinnervation change that may be many years old, while IDFs are changing type when biopsied and thus reveal recent reinnervation and preceding denervation. IDFs usefully belong with the histochemical indicators used to evaluate muscle disease.
Electrophysiological and ultrastructural studies on reversible neural conduction disturbance after high voltage discharge
Authors: Eickhorn Roland , Manfred Kopf , Stadler Rainer , Antoni Hermann 
Published: January 2005

AbstractHigh‐voltage condenser discharges exerting a field strength of up to 1000 V/cm (discharge time constant 0.24‐8 msec) applied to isolated sciatic frog nerve lead to disturbances of the propagation of action potentials including transient complete block of conduction. Such conduction disturbances are normally reversible within minutes. Inhibition of the activity of the membrane–bound Na+‐K+ATPase prevents the recovery from conduction block. Withdrawal of external Ca2+ also prevents recovery, whereas blockade of protein synthesis by cycloheximide has no influence. The velocity of recovery depends on the temperature, with temperature coefficients (Q10) from 1.31 to 1.84 between 2° and 30°C. Transmission electron microscopy of nerves subjected to strong discharges shows alterations of the myelin sheath (splitting and cleft formation) which are, however, not specific for this mechanism of injury. No alterations are seen in the region of the free axoplasmic membrane of the node of Ranvier or in organelles. The results suggest a breakdown of the transmembrane ionic gradient causing the conduction disturbance.
Properties of motor unit action potentials recorded with concentric and monopolar needle electrodes: ADEMG analysis
Authors: Howard Jane E. , McGill Kevin C. , Dorfman Leslie J. 
Published: January 2005

AbstractWe compared the configurational and firing properties of 7270 motor unit action potentials (MUAPs) recorded with either concentric (CNE) or monopolar (MNE) needle electrodes from the brachial biceps and anterior tibial muscles of 10 healthy young adults (mean age 27 ± 4.5 years) using automatic decomposition electromyography (ADEMG). In both muscles, mean MUAP amplitude, rise rate, and number of turns were significantly greater when recorded with MNE (paired t‐test, P < 0.001 in each case). Similar findings were observed at all three tested levels of isometric contractile force: threshold, 10% of maximum voluntary contraction (MVC), and 30% MVC. In contrast, there was no significant difference between electrode types on measurements of mean MUAP duration or firing rate (P > 0.05 in each case). These findings indicate that it is acceptable to generalize normative data on MUAP duration and firing rate from one electrode type to another, but that measures of MUAP amplitude and complexity require independent normative databases.
Cold‐induced peripheral nerve damage: Involvement of touch receptors of the foot
Authors: Carter Jonathan L. , Shefner Jeremy M. , Krarup Christian 
Published: January 2005

AbstractA 31‐year‐old male developed paresthesia and numbness of mainly the right foot following exposure to nonfreezing temperatures under moist conditions over a period of 1 week. The symptoms gradually improved over several months. When seen for electrophysiological studies 6 months after the injury, there was no sensory loss on clinical examination, although he continued to complain of distal numbness of the right foot. The right extensor digitorum brevis muscle was atrophic, and the distal motor latency in the peroneal nerve was prolonged. Conduction studies of the right sural nerve showed a predominantly distal diminution of the SAP evoked by electrical stimulation at the dorsum pedis. Action potentials evoked by tactile stimulation of Pacinian corpuscles showed a prolonged latency on the symptomatic side, suggesting that the most pronounced pathological changes in immersion injury may be localized to the very distal portion of the nerve at the nerve fiber‐receptor junction.
The utility of magnetic stimulation for routine peripheral nerve conduction studies
Authors: Evans Bruce A. , Litchy William J. , Daube Jasper R. 
Published: January 2005

AbstractThe magnetic stimulator was compared with percutaneous electrical stimulation for activation of the median nerve at the wrist in four volunteers. Magnetic stimulation was unable to achieve supramaximal stimulation without activation of the ulnar nerve. The point of nerve depolarization could not be reliably estimated from the relationship of the stimulator head to the nerve. We conclude that the magnetic stimulator coil is as yet not suitable for routine electrodiagnositic use in the peripheral nervous system.
AAEE minimonograph #32: The electrophysiologic examination in patients with radiculopathies
Authors: Wilbourn Asa J. , Aminoff Michael J. 
Published: January 2005

AbstractA brief history of the evolution of radiculopathy as a clinical entity, and the use of electrodiagnostic studies to diagnose it, are provided. Root anatomy and the concept of myotomes and dermatomes are reviewed, as is the pathophysiology of radiculopathy. The value and limitations of the various electrophysiologic procedures used in the diagnosis of radiculopathies are discussed, including motor and sensory nerve conduction studies, late responses, somatosensory evoked potentials, nerve root stimulation, and the needle electrode examination. The specific muscles are enumerated which most often appear abnormal on needle electromyography with lesions of the various roots. The electrodiagnostic differentiation of root lesions from plexus lesions is described, and the various electrodiagnostic findings with lumbar canal stenosis are discussed. Finally, the value and limitations of the electrodiagnostic assessment in the evaluation of patients with suspected radiculopathies are reviewed.
Posterior femoral cutaneous neuralgia
Authors: Chutkow Jerry G. 
Published: January 2005

AbstractA middle‐aged male developed a right posterior femoral cutaneous neuralgia that persisted for 10 years without any associated neurologic, electrophysiologic, or radiologic findings. Five years after onset, surgical exploration of the subgluteal area identified a venous malformation surrounding the nerve. The syndrome appears unique and exemplifies all major aspects of the sensory distribution of the nerve complex.
A comparison of EMG procedures in the carpal tunnel syndrome with clinical‐EMG correlations
Authors: White James C. , Hansen Susan R. , Johnson Richard K. 
Published: January 2005

AbstractOne hundred and twenty‐two patients were selected on the basis of symptoms of finger numbness and tingling thought to suggest carpal tunnel syndrome. The severity of the symptoms was graded and the patients were studied with seven established EMG procedures, motor inching to the abductor pollicis brevis and second lumbrical muscles, and sensory inching. Symptom severity was compared with the degree of nerve conduction abnormality and results from symptomatic hands with those abnormal results from patient's asymptomatic hands. Motor inching to the abductor pollicis brevis muscle was the most sensitive study and, when combined with sensory inching, gave a sensitivity of 97–100% (depending on symptom severity). Motor inching to the second lumbrical muscle alone detected the lesion site in several severely involved nerves. Guidelines are suggested with which one can estimate the likelihood that a patient's finger sensory symptoms are on the basis of carpal tunnel syndrome.
AAEE case report #16: Botulism
Authors: Pickett Jackson B. 
Published: January 2005

AbstractBotulinal toxin causes a marked reduction in the number of quanta released by autonomic and motor nerve terminals. As a result it causes blurred vision, inability to move the eyes, weakness of other cranial nerve‐innervated muscles, dyspnea progressing to apnea, and generalized weakness. Electrodiagnostic findings in severe botulism can be relatively nonspecific, with low amplitude and short duration motor unit action potentials and small M wave amplitudes. A modest increment in M wave amplitude with rapid repetitive nerve stimulation may help to localize the disorder to the neuromuscular junction. Identification of the toxin in the patient's serum is diagnostic. The treatment of botulism is mainly supportive.
Silver cholinesterase immunocytochemistry: A new neuromuscular junction stain
Authors: Alderson Kathy , Pestronk Alan , Yee Woon‐Che , Drachman Daniel B. 
Published: January 2005

AbstractEvaluation of morphological alterations at the neuromuscular junction associated with sprouting or other pathological changes has been limited by the inability to visualize simultaneously the multiple cell types that make up a junction. A new combined stain for the concurrent demonstration of motor nerve terminals, cholinesterase, and Schwann cell myelin and other antigens at neuromuscular junctions using bromoindoxyl acetate dye staining for cholinesterase, silver‐gold impregnation for nerve terminals, and immunocytochemistry of selected antigens is described. The clarity of the stain permits graphic demonstration of the alteration of neuromuscular junction components during sprouting as well as other pathological changes.
Motor neuropathy with multifocal conduction blocks
Authors: van den Bergh Peter , Logigian Eric L. , Kelly John J. 
Published: January 2005

AbstractWe describe a patient with a chronic, symmetric, monophasic, acquired, pure motor, demyelinating polyneuropathy. Electrodiagnostic studies showed the presence of multifocal conduction blocks in motor nerves at sites not prone to compression. A sural nerve biopsy was normal. The patient responded to immunosuppressive therapy and plasma exchange. We postulate that this disorder is an unusual variant of chronic inflammatory polyradiculoneuropathy.
Asymptomatic hyper‐CK‐emia: An electrophysiologic and histopathologic study
Authors: Joy Juan L. , Oh Shin J. 
Published: January 2005

AbstractSince the popularization of routine creatine kinase (CK) measurement, an increasing number of patients with unexplained CK elevation (“asymptomatic hyper‐CK‐emia”) are being identified. We studied 19 patients with persistent CK elevation of unknown etiology with electromyography (EMG) and muscle biopsy. Needle EMG was abnormal in 14 patients. Muscle biopsy was positive in all individuals with abnormal EMG and in one patient with normal EMG. Diagnoses included polymyositis in five patients, morphologically nonspecific myopathy in three, mitochondrial myopathy in two, and sarcoid myopathy, central core disease, multicore disease, inclusion body myopathy, and McArdle's disease in one case, respectively. Five patients with abnormal biopsies developed weakness within 1 year of presentation. We conclude that persistent asymptomatic CK elevation represents mild or early myopathy in a majority of cases.
Muscle pain associated with tubular aggregates and structures resembling cylindrical spirals
Authors: Danon Moris J. , Carpenter Stirling , Harati Yadollah 
Published: January 2005

AbstractA 42‐year‐old man complained of muscle pain in the legs and episodes of left‐sided limb weakness. Light microscopy of his quadriceps muscle showed abundant subsarcolemmal accumulations with typical histochemical features for tubular aggregates. Electron microscopy showed areas filled with tubular aggregates and vesicular profiles. Scattered within some of the tubular aggregates circular profiles reminiscent of cylindrical spirals were seen. The presence of structures resembling cylindrical spirals within tubular aggregates suggest that they may arise from a component of the sarcoplasmic reticulum. There appears to be an intimate relationship between myalgia and these various types of abnormal membranous profiles; however, the pathophysiology remains to be elucidated.
The application of nerve conduction and clinical studies to genetic counseling in hereditary motor and sensory neuropathy type I
Authors: Berciano Josée , Combarros Onofre , Calleja Jesús , Polo Josée M. , Leno Carlos 
Published: January 2005

AbstractOne hundred and thirty two individuals at risk for hereditary motor and sensory neuropathy (HMSN) type I from 11 unrelated families were evaluated by physical examination. Motor conduction velocity (MCV) studies of median and/or peroneal nerves were performed on 99 of them. Seventy‐three subjects were found to be affected. In all age categories including the first decade of life, the ratio of affected individuals at risk did not significantly differ from the expected 1:1 ratio; that is, penetrance of the gene was complete. The majority of affected members in the first decade had no clinical features considered diagnostic of peroneal muscular atrophy syndrome, and full clinical expression developed in the second decade. Marked slowing of MCV was already present in the early years of life, even as young as 6 months. Moreover serial MCV studies carried out throughout the first year of life in an affected girl showed no physiological increase in conduction velocity. For purposes of genetic counseling, our experience suggests that, starting from 6 months of age, a clinically and electrophysiologically normal subject has a zero risk of having inherited the HMSN type I gene. However given the limited numbers in this series, infants at risk with normal clinical evaluation and MCVs should be followed up yearly up to 5 years of age.
Muscle protein synthesis in steroid‐induced proximal myopathy: A case report
Authors: Pacy Paul J. , Halliday David 
Published: January 2005

AbstractA 51‐year‐old man with proven adenosquamous carcinoma of the lung presented with clinically acute steroid myopathy. Postabsorptive whole body leucine kinetics and fractional mixed muscle protein synthesis rate (MPSR) were determined by a steady‐state approach during continuous L‐(1–13C) leucine infusion. Plasma 13C α‐ketoisocaproic acid enrichment was taken to represent labeling of the precursor pool. Postabsorptive whole body leucine flux and protein synthesis were less than the 1 in 500 confidence intervals of control values. Fractional MPSR was significantly reduced (P < 0.01). Simultaneous calculation of MPSR from two adjacent sites was in excellent agreement (0.0372 and 0.0395% h−1). This is the first report that steroid myopathy is associated with reduced whole body protein synthesis and fractional MPSR in man.