bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impressions of neurology and neurosurgery in the People's Republic of China
Authors: Tower Donald B. , Feindel William 
Published: January 2005

AbstractDuring July, 1979, the authors visited the neurological and neurosurgical services of eight major hospitals and associated medical schools in Peking, Tientsin, and Shanghai, and viewed many of their teaching and research facilities. From these visits and our discussions with the staffs of these units, we came away with the impressions reported here.In the people's Republic of China today there are more than 2,000 neurologists and 1,300 neurosurgeons. At present there are two major clinical centers: the Peking Institute of Neurosurgery, directed by Prof Wang Chung‐Cheng and located in the Xuan Wu Hospital affiliated with the Peking First Medical College; and the Shanghai Institute of Neurology, directed by Prof Chang Yuan‐Cheng and located in the Hua San Hospital affiliated with the Shanghai First Medical College. In every hospital, patient loads are formidable (e.g., several thousand outpatients weekly), but the variety of clinical problems does not differ from those seen elsewhere in the world. The most common problems are head injuries, brain tumors, cerebrovascular disorders, infections, and epilepsy.Each of the centers is heavily engaged in undergraduate and postgraduate training, and research has been resumed after the major disruptions of the 1966—76 „Cultural Revolution.”︁ Research continues on acupuncture, but present emphasis is directed toward pain mechanisms, notably at the Shanghai Institute of Physiology, directed by Prof Feng De‐Pei. We were most impressed by this, the principal neurophysiology and neuroscience research center in the country.Clearly, the People's Republic of China has a wealth of clinical material and many competent neurologists and neurosurgeons with stimulating research idesas—characteristics which offer real potentials for collaborative research.
Dyslexia: Regional differences in brain electrical activity by topographic mapping
Authors: Duffy Frank H. , Denckla Martha B. , Bartels Peter H. , Sandini Giulio 
Published: January 2005

AbstractElectroencephalographic (EEG) and evoked potential data were recorded during behavioral testing from 8 dyslexic and 10 normal boys aged 9 to 11 years. Topographic mapping of their brain electrical activity revealed four discrete regions of difference between the two groups involving both hemispheres, left more than right. Aberrant dyslexic physiology was not restricted to a single locus but was found in much of the cortical region ordinarily involved in reading and speech. Prominent group differences were observed in the bifrontal area in addition to the more expected left temporal and left posterior quadrant regions. Although activation tests produced more prominent group difference, dyslexics differed from normal subjects at rest as well. EEG alpha activity was increased for the dyslexics, suggesting relative cortical inactivity in that group.
Cylindrical spirals in a familial neuromuscular disorder
Authors: Bove Kevin E. , Iannaccone Susan T. , Hilton Pamela K. , Samaha Frederick 
Published: January 2005

AbstractCylindrical spirals are unique membranous structures that were detected in skeletal muscle of a mother and one of her two children; all three have percussion myotonia but no evidence of weak or wasted skeletal muscles. Muscle cramps, stiffness, posteffort muscle tightness, myotonic lid lag, and the cylinders appear or progress with age, but the disorder is asymptomatic in the children and only mildly incapacitating in the mother. The cylinders are 8 μ long and 1 μ wide, are composed of spiraling double‐laminate membrane resembling myelin, and are derived from abnormal subsarcolemmal tubulovesicular structures that are interpreted as pathological T‐tubes.
Neuropathology of phenylacetate poisoning in rats: An experimental model of phenylketonuria
Authors: Wen G. Y. , Wisniewski H. M. , Shek J. W. , Loo Y. H. , Fulton T. R. 
Published: January 2005

AbstractResults of this investigation indicate that the suckling rat treated with phenylacetate should be a useful new model for studying the pathogenesis of phenylketonuria and neuronal development. Both cerebellar and retinal neurons of postnatally treated rats are vulnerable to the adverse effects of phenylacetate. Morphological changes observed in the cerebellum, retina, and optic nerve of treated animals during the fourth to twenty‐first days of life consist of regional reduction in the size of cerebellar vermis lobules IV, V, VIa, and IX, 35 to 40% reduction in thickness of the molecular layer, accumulation of cerebellar external granular cells and retinal neuroblastic cells, fewer parallel fibers in the cerebellar cortex, and fewer myelinated axons in the optic nerve.
Failure to detect abnormal fatty acid profiles in serum lipoproteins in Friedreich's ataxia
Authors: Walker Janet L. , Chamberlain Susan , Robinson Norman 
Published: January 2005

AbstractA recent report indicated an association between the spinocerebellar degeneration of Friedreich's ataxia and abnormal fatty acid profiles of the cholesterol ester fraction in both total plasma and high‐density lipoprotein. In an effort to substantiate these findings in lipoproteins, we estimated fatty acid profiles of total high‐density lipoprotein and the cholesterol esters of high‐ and low‐density lipoproteins. Those profiles in 10 Friedreich's ataxia patients compared well with previously reported normal values and did not differ significantly from results in 10 age‐matched controls.
Changes in endoneurial fluid pressure, permeability, and peripheral nerve ultrastructure in experimental lead neuropathy
Authors: Myers Robert R. , Powell Henry C. , Shapiro Harvey M. , Costello Michael L. , Lampert Peter W. 
Published: January 2005

AbstractThe dynamics of endoneurial edema were studied by quantifying endoneurial fluid pressure (EFP) during the development of lead neuropathy and correlating these data with changes in blood‐nerve barrier permeability and with morphological alterations in nerves, capillaries, and Schwann cells. EFP measured from the sciatic nerve in control Long‐Evans rats was 2.1 ± 1.0 cm H2O. EFP was significantly elevated 7 weeks after animals were started on a diet containing 6% lead carbonate, and it increased progressively until a plateau in pressure was reached between weeks 9 and 11. Thereafter, EFP gradually returned to normal values. The progressive increase in EFP was highly correlated with the extravasation of osmotically active macromolecules, traced by fluorescein isothiocyanatedextran compounds of graded molecular weight and by horseradish peroxidase (HRP). Electron microscopy revealed extravasation of HRP between endothelial cells, intranuclear inclusions characteristic of lead poisoning in Schwann cell nuclei, demyelination, and remyelination. The observation of intranuclear inclusions consistent with lead deposition in Schwann cells strengthens the hypothesis that extravasated lead in the interstitial fluid causes direct injury to Schwann cells, giving rise to demyelination. Nerve compliance was determined.
Lafora disease: Diagnosis by liver biopsy
Authors: Nishimura R. N. , Ishak K. G. , Reddick R. , Porter R. , James S. , Barranger J. A. 
Published: January 2005

AbstractWe have studied four patients who had a clinical course compatible with Lafora disease. The diagnosis was confirmed in one by the presence of Lafora bodies in central nervous system neurons at autopsy and was supported in another by findings in the cerebral biopsy of a sibling. Our patients had no clinically apparent liver disease, but liver specimens in each instance showed a distinctive histological abnormality, with hepatocytes containing inclusions having a ground‐glass appearance. The liver biopsy findings appear to be relatively specific for this disorder and can easily be differentiated from those in other liver diseases.
Somatosensory evoked potentials following trigeminal nerve stimulation in trigeminal neuralgia
Authors: Stöhr M. , Petruch F. , Scheglmann K. 
Published: January 2005

AbstractThe examination of somatosensory evoked potentials following trigeminal nerve stimulation in 20 subjects with idiopathic trigeminal neuralgia revealed a pathological increase in latency of the first positive component on the involved siEN in 7 (41%) of the 17 patients without anteceENnt surgical treatment. The mean difference in latency between the two siENs was 1.3 msec (2p ≥ 0.005). These results are indicative of microtraumatization of the trigeminal nerve in the posterior fossa by blood vessels, for example, leading to local ENmyelinization. The method seems to be of diagnostic value in selecting patients for nerve ENcompression by posterior fossa operations.
Pattern‐reversal visual evoked potentials in the hereditary ataxias and spinal degenerations
Authors: Bird Thomas D. , Crill Wayne E. 
Published: January 2005

AbstractPattern‐reversal visual evoked potentials (PRVEP) were evaluated in 24 patients from 18 separate families with various forms of hereditary ataxia and spinal degeneration. Abnormally delayed latencies were found in 3 of 5 patients with classic Friedreich's ataxia, 1 patient with dominant spastic paraparesis, and 1 patient with recessive dentatorubrospinal degeneration. Fifteen other patients with several different types of dominant and recessive hereditary ataxias had normal PRVEP latencies, including 1 patient with bilateral optic atrophy. Testing of PRVEP will be useful in the clinical delineation of the genetic ataxias and spinal degenerations, and, when interpreted with caution, should be an additional variable evaluated in the differentiation of these disorders from multiple sclerosis.
The role of hydrostatic pressure in ischemic brain edema
Authors: Kogure Kyuya , Busto Raul , Scheinberg Peritz 
Published: January 2005

AbstractThe mechanisms responsible for early prenecrotic ischemic brain edema were investigated in rats by comparing brain metabolism, tissue water (HOH) content, and sodium and potassium ion concentration in brain during ischemia induced by decapitation, by the Pulsinelli‐Brierley technique, and by carotid embolization. Although brain metabolic functions were similarly disturbed in all three groups, an increase in brain HOH occurred only in the embolism model, which allowed collateral perfusion. Early ischemic brain edema is therefore dependent upon (1) impaired energy‐dependent ion pumps and (2) a hydrostatic pressure gradient from patent vascular lumens. Elevated perfusion pressure increases the extent of this early edema. Induced hypertension causes impairment of blood‐brain barrier function, as evidenced by extravasation of Evans blue dye 5 minutes after embolic ischemia, and strikingly increases the extent of macromolecular extravasation 4 hours after ictus. This increased protein leakage is accompanied by elevated HOH content and sodium concentration, as compared to findings in normotensive animals. It is concluded that the use of induced hypertension as a therapeutic modality in patients with acute stroke may be harmful.
Reduced glycine receptor in the spinal cord in amyotrophic lateral sclerosis
Authors: Hayashi Hideaki , Suga Masakazu , Satake Mei , Tsubaki Tadao 
Published: January 2005

AbstractTransmitter receptor binding was estimated in the spinal cord of 6 subjects with amyotrophic lateral sclerosis (ALS) and 4 control subjects in assays using 3H‐quinuclidinyl benzilate for muscarinic cholinergic receptors, 3H‐strychnine for glycinergic receptors, 3H‐spiroperidol for dopaminergic receptors, 3H‐muscimol for GABAergic receptors, and 3H‐dihydroalprenolol for β‐adrenergic receptors. In ALS, glycinergic receptor binding was greatly reduced in the anterior gray matter. This finding may be attributed to loss of large neurons in the anterior gray matter, known to be characteristic of ALS.
Sleep apnea and hypoventilation syndrome associated with acquired nonprogressive dysautonomia: Clinical and pathological studies in a child
Authors: Frank Yitzchak , Kravath Richard E. , Inoue Kiyoharu , Hirano Asao , Pollak Charles P. , Rosenberg Roger N. , Weitzman Elliot D. 
Published: January 2005

AbstractA 6‐year‐old girl had subacute onset of hypoventilation and apnea during sleep. Diffuse dysautonomic changes were identified, including dilated, nonreactive pupils, decreased tearing and sweating, and abnormal temperature and cardiovascular control. All‐night polysomnographic studies revealed frequent obstructive and central sleep apnea episodes. Her serum contained cytotoxic antineuroblastoma immunoglobulins. She died two years later during sleep. The general pathological examination revealed a ganglioneuroma originating in the sympathetic ganglia. Abnormalities in the brain were confined to the brainstem and consisted of complete loss of neurons with severe fibrillary gliosis in the region of the Edinger‐Westphal nuclei as well as loss of neurons with gliosis in the locus ceruleus and in the reticular formation bilaterally.
Seizures, hypoxic‐ischemic brain injury, and intraventricular hemorrhage in the newborn
Authors: Hill Alan , Volpe Joseph J. 
Published: January 2005

AbstractThis review deals with neonatal seizures, perinatal hypoxic‐ischemic brain injury, and neonatal intraventricular hemorrhage. Neonatal seizures are the most prominent signals of the largest number of neonatal neurological disorders. The convulsive phenomena may be subtle. The predominant etiological process is hypoxic‐ischemic encephalopathy. Prognosis is related primarily to the neurological disease responsible for the seizures. Treatment may be specific for the underlying disorder (e.g., glucose or calcium) or less specific (i.e., therapy with anticonvulsant drugs). Prompt control of the seizures is important to avoid brain injury secondary to the effects of the seizures on ventilation, perfusion, and brain metabolism.Hypoxic‐ischemic encephalopathy in the newborn most often is a consequece of intrauterine asphyxia. Diagnosis depends primarily on recognition of the clinical syndrome but also on a variety of neurodiagnostic techniques, including radionuclide and CT brain scans. Prognosis is estimated best by a combination of clinical analysis and specialized neurodiagnostic studies. Management is based principally on vigorous support, particularly of ventilation and perfusion, maintenance of adequate glucose influx, and control of seizures.Intraventricular hemorrhage is the most common type of neonatal intracranial hemorrhage. The neuropathology is characterized by bleeding from capillaries of the subependymal germinal matrix. Secondary rupture of the ependymal lining then causes intraventricular hemorrhage. Pathogenesis relates to the anatomy of the germinal matrix, the distribution and regulation of cerebral blood flow, and the structure and vulnerability of periventricular capilaries. Precise diagnosis requires a brain imaging procedure; portable, real‐time ultrasound is the preferred approach for critically ill infants. Prognosis relates to the severity of the hemorrhage as well as any preceding hypoxic‐ischemic insults and the subsequent occurrence of hydrocephalus. Choice of therapy for posthemorrhagic ventricular dilation depends upon severity and rapidity of progression and ranges from close observation only to ventriculoperitoneal shunting.
Neclear medicine in clinical neurology: An update
Authors: Oldendorf William H. 
Published: January 2005

AbstractIsotope scanning using technetium 99m pertechnetate has fallen into disue since the advent of x‐ray computerized tomography. Regional brain blood flow studies have been demonstrated and is of use in localizing such foci. Cisternography as a predictive tool in normal pressure hydrocephalus is fallin into disue. Positron tomographic scanning is a potent research tool that can demonstrate both regional glycolysis and blood flow. Unfortunately, it is extremely expensive and complex to apply in a clinical setting. With support from the National Institutes of Health, seven extramural centers have been funded to develop positron tomographic capabilities, and they will greatly advance our knowledge of stroke pathophysiology, seizure disorders brain tumors and various degenerative diseases. Nuclear magnetic resonance imaging is a potentially valuable tool since it creates tomographic images representing the distribution of brain water. No tissue ionization is produced, and images comparable to second‐generation computerized tomographic scans are already being produced in humans.
Development of a tomographic myelin scan
Authors: Frey K. A. , Wieland D. M. , Brown L. E. , Rogers W. L. , Agranoff B. W. 
Published: January 2005

AbstractThe principle that myelin can be imaged nonivnvasiely using the emission tomographic distribution of a lipophilic radioactive tracer was investigated. Properties of agents suitable for noninvasive myelin scanning are discussed with specific reference to blood‐brain barrier permeability, metabolism, and tracer lipophilicity. The brain distributions of inert tracers are correlated with their partitioning between octanol and saline. A test probe, iodobenzene, was labeled with iodine 125 for preliminary invasive studies in the rabbit. The equilibrium brain distribution, determined either autoradiographically of by regional dissection, corresponded closely to that of myelin. 123I‐labeled iodobenzene, a gamma‐emitting analog, was then administered to a monkey, and tomographic reconstruction revealed a pattern of brain uptake corresponding to white matter.
Extraneural metastases in childhood brain tumors
Authors: Duffner Patricia K. , Cohen Michael E. 
Published: January 2005

AbstractAlthogh extraneural metastases are known to occur with primary tumors of the central system, they are considered a rarity. Large autopsy series have place the frequency at 0.4 to 0.5%. At the roswell Park Memorial Institute, 36 children with brain tumors have been treated with a combination of surgery, radiotherapy, and chemotherapy in the past 12 years. We recently reviewed the autopsies obtained on 15 of these children and found that 4 (26%) had extraneural metastases. An additional child, who was not autopsied, had extraneural extension diagnosed during life.This inordinately high incidence of metastases outside the nervous system in children with aggressively trated brain tumors raises questions about their cause. The prolonged survival of these patients may have allowed growth of sufficient generations of extracranial metastatic cells for the extraneural disease to become clinically significant. Another possibility is that chemotherapy may alter the patients' immune system and thus promote extracranial tumor growth. As larger numbers of childhood brain tumors are managed with multimodality therapy, it may be possible to evaluate the extent to which tratment allows intracranial neoplasms to spread outside the nervous system.
Endorphins in experimental spinal injury: Therapeutic effect of naloxone
Authors: Faden A. I. , Jacobs T. P. , Mougey E. , Holaday J. W. 
Published: January 2005

AbstractAn experimental model of cat spinal injury was used to investigate the hypotheses that endorphins are involved in the pathophysiology of spinal cord injury and that the opiate antagonist naloxone, by blocking the effects of endorphins, may improve physiological and neurological recovery. Experimental trauma to the cervical spine casued a reduction in blood pressure and spinal cord blood flow (SCBF) associated with increased plasma levels of β‐endorphin–like immunoreactivity; both blood pressure and SCBF were significantly improved by naloxone treatment. Naloxone‐treated animals also showed less prominent spinal cord abnormalities and significantly improved neurological recovery compared with saline controls. Moreover, both the pathological and clinical findings correlated significantly with the blood pressure changes following treatment. The data support a pathophysiological role for endorphins in experimental spinal cord injury and suggest that opiate antagonists might improve the treatment of spinal trauma in humans.
Pharyngoesophageal motor function in patients with myotonic dystrophy
Authors: Swick H. M. , Werlin S. L. , Dodds W. J. , Hogan W. J. 
Published: January 2005

AbstractSix adults with myotonic dystrophy underwent detailed radiological and manometric studies of pharyngoesophageal function. Four of the patients had no history of swallowing dysfunction, while two had very mild symptoms. All patients showed abnormalities of pharyngoesophageal function. Pharyngeal peristalsis was present but of low amplitude. Resting upper esophageal sphincter pressure was diminished, but the sphincter relaxed normally. Peristalsis in the esophageal body was in variably absent in the striated muscle segment of the esophagus and was either absent or decreased in amplitude in the smooth muscle segment. The lower esophageal sphincter was normal. Myotonia did not occur in the sphincters or the esophageal body. These findings suggest that phyaryngoesophageal dysfunction is common in patients with myotonic dystrophy, even when clinical symptoms are absent. The abnormalities are probably related to muscle weakness rather than to myotonia in the pharyngeal and esophageal musculature.
Effects of dipropylacetate on brain development
Authors: Diaz Jaime , Shields W. Donald 
Published: January 2005

AbstractDipropylacetate (DPA; valproci acid) is a new anticonvulsant reported to be effective in many types of seizures, including those that occur early in life. This study describes the effects of chronic administration of DPA upon a developing organism. Four‐day‐old rat pups were injected daily with either 75 mg/kg DPA, 200 mg/kg DPA, or vehicle until day 18. Administration of DPA resulted in decreased body and organ weights, with the greatest reductions in the 200 mg/kg group. To control caloric intake, an additional experiment was conducted. Animals were injected with either vehicle or 200 mg/kg DPA. Each animal was implanted with a chronic intragastric cannula and fed through the cannula. The results of this experiment indicated that body and organ weights were the same for both vehicle and drug groups, except for brain. The animals receiving DPA had significant deficits of 12% in total brain weight and 22% in weight of the cerebellum. The data suggest that chronic administration of DPA early in life may have adverse consequences on brain growth.
Retardation of schwann cell division and axonal regrowth following nerve crush in experimental lead neuropathy
Authors: Ohnishi Akio , Dyck Peter James 
Published: January 2005

AbstractIn experimental lead neuropathy, Schwann cells undergo segmental demyelination and possibly cell death and, concurrently, remyelination and multiplication to create new internodes of myelin and onion bulb formations. In rats fed 4% lead carbonate for three months, the ability of Schwann cells to divide (percentage showing mitotic figures, labeling index, and total number per millimeter of fascicular length of nerve) was studied serially for four weeks. Schwann cell events were also compared in sural nerve distal to crush with and without resection of an intervening length of nerve. In both cases, Schwann cell multiplication as a result of axotomy was retarded in lead‐intoxicated as compared to control animals. On the average, regrown myelinated axons four weeks after and 10 mm below the point of crush in lead‐treated animals were similar in number and smaller in caliber, but they exhibited a normal relationship of myelin thickness to axonal area compared with control animals. These studies provide evidence that Schwann cell division and axonal regrowth after crush are retarded in experimental lead neuropathy.