bluuebunny/crossref_metadata_2025_split huggingface dataset:
Voluntary activation and fiber density of fasciculations in motor neuron disease
Authors: Guiloff Roberto J. , Modarres‐Sadeghi Hamid 
Published: January 2005

AbstractTwo hundred voluntarily activated motor units and 211 fasciculations were recorded in the biceps of 10 patients with motor neuron disease with the Macro EMG technique. Twenty‐two fasciculating, in nine of 10 muscles, had a potential of closely similar shape, amplitude, and area to that of a voluntary unit. Fasciculating units that could not be activated voluntarily had a higher mean number of spikes in their triggering single fiber potentials than units that could only be activated voluntarily, but statistically similar Macro EMG parameters. The mean number of single fiber spikes, and Macro EMG parameters, of fasciculations activated voluntarily, were similar to those of units that were only activated voluntarily. A positive correlation between fiber density and Macro EMG median amplitude and area in individual patients, and between number of single fiber spikes and Macro EMG amplitudes and areas in the pooled data, was found for fasciculations but not for voluntary units. At least 10% of fasciculations in patients with motor neuron disease may originate near or above the point of axonal branching and a proportion of those without evidence of voluntary activation may have a higher number of smaller muscle fibers, or more closely packed muscle fibers, of similar or greater size, than voluntarily activated motor units. Differences in the peripheral microanatomy of a number of fasciculation units not activated voluntarily may underlie ectopic impulse generation in the terminal axonal arborization, endplate zone, or muscle fibers of these units.
JC virus infection and Alzheimer's disease: Reappraisal of an in situ hybridization approach
Authors: Heinonen Outi , Syrjänen Stina , Mäntyjärvi Rauno , Syrjänen Kari , Riekkinen Paavo 
Published: January 2005

AbstractTo assess the validity of the recently reported data on frequent occurrence of latent JC virus (JCV) infections in the brains of patients with Alzheimer's disease, we used in situ hybridization with biotinylated whole genomic JCV probes and the streptavidin‐biotinylated alkaline phosphatase method to examine brain sections of such patients. We did not find any signs of JCV either in the brains of the patients with Alzheimer's disease or in those of nondemented, elderly control patients. Nonspecific staining of corpora amylacea–like bodies, however, was invariably detected with in situ hybridization using JCV probes.
Prognostic value of cytogenetic analysis in human cerebral astrocytomas
Authors: Kimmel David W. , O'Fallon Judith R. , Scheithauer Bernd W. , Kelly Patrick J. , Dewald Gordon W. , Jenkins Robert B. 
Published: January 2005

AbstractCytogenetic analysis has become an important part of the diagnostic evaluation of most hematological neoplasms. However, there is limited information on the value of cytogenetic analysis in most solid tumors, including cerebral astrocytomas. This report summarizes a prospective cytogenetic study of 99 human cerebral astrocytomas, 16 mixed oligoastrocytomas, and 2 gliosarcomas. The cytogenetic procedure involved in situ culture and robotic harvesting techniques. Correlative clinical and survival data were available on all patients. We successfully cultured and obtained suitable metaphases in 107 of the 117 tumors. One or more chromosomally abnormal clones were observed in 72 tumors, and nonclonal or normal karyotypes were observed in 35 tumors. In a multivariate analysis, survival time was significantly better in patients whose tumors had normal or nonclonal karyotypes on cytogenetic analyses than in those whose tumors had clonal abnormalities (p = 0.0071). Our study demonstrates that cytogenetic analysis provides independent prognostic information in patients with cerebral astrocytomas.
Recent progress toward understanding the molecular biology of von Recklinghausen neurofibromatosis
Authors: Gutmann David H. , Collins Francis S. 
Published: January 2005

AbstractThe gene for von Recklinghausen neurofibromatosis (NF1) was recently identified by positional cloning and found to code for a large, ubiquitously expressed protein. This protein has both structural and functional similarity to a family of proteins with guanosine triphosphatase–activating properties, involved in the regulation of the protooncogene ras. One of the postulated functions of the NF1 gene product may relate to its ability to regulate ras‐mediated cell proliferation. Selective pharmacotherapy directed at downregulating ras may be of benefit to patients with NF1.
The transcription factor Sp1 binds to the JC virus promoter and is selectively expressed in glial cells in human brain
Authors: Henson John , Saffer Jeffrey , Furneaux Henry 
Published: January 2005

AbstractJC virus is a human DNA virus that specifically infects oligodendroglial cells, resulting in a demyelinating disease (progressive multifocal leukoencephalopathy) of the central nervous system of immunosuppressed patients. The hostrange restriction of JC virus is controlled at the level of viral gene transcription. To analyze further the determinants of glial specificity, we cloned and sequenced the JC viral early promoter elements directly from the infected brain tissue of four patients. The promoter of each isolate contained a novel identical sequence, 5′‐AGGGAGGAGC(GA box), located immediately upstream of the TATA box. This GA box is not present in the original isolate of JC virus (Mad‐1 strain), which was obtained after numerous passages in tissue culture. The GA box has 80% homology with the consensus binding site for the transcription factor Sp1. Using a gel retardation assay, we found that Sp1 binds to the GA box. Alteration of bases within the sequence abolished binding of Sp1, demonstrating sequence specificity of binding. Immunohistochemical localization of Sp1 expression in human brain reveals that expression is restricted to the nuclei of oligodendroglial cells, cerebellar basket cells, and endothelial cells. The GA box is present in the promoters of the myelin basic protein and proteolipid protein genes. On the basis of these observations, we suggest that this Sp1‐like binding site participates in the control of glial‐specific gene expression.
Multiple sclerosis in children: Cerebral metabolic alterations monitored by localized proton magnetic resonance spectroscopy in vivo
Authors: Bruhn H. , Frahm J. , Merboldt K. D. , DiplMath W. Hänicke , Hanefeld F. , Christen H. J. , Kruse B. , Bauer H. J. 
Published: January 2005

AbstractIn vivo proton magnetic resonance spectroscopy of 8 children (7–16 years) with established multiple sclerosis revealed distinct alterations in regional cerebral metabolism associated with different aspects of the disease: (1) Localized proton spectra (2 to 4‐ml volumes of interest) from multiple sclerosis plaques were generally characterized by a decrease in N‐acetylaspartate and creatines, and an increase in cholines and myo‐inositol relative to age‐matched control subjects, (2) neither chronic nor enhancing plaques (by gadolinium‐diethylenetriamine pentaacetic acid) during an acute exacerbation showed elevated levels of lactate or lipids, (3) spectra from adjacent white matter that did not appear suspicious in magnetic resonance images were similar to those of normal control subjects, and (4) cortical gray matter related to neighboring multiple sclerosis lesions showed a notable reduction of N‐acetylaspartate. The present results show that functional impairment in multiple sclerosis is linked to gross metabolic disturbances of neuronal cell chemistry. We suggest that focal demyelination is accompanied by increased membrane precursors of proliferative turnover and is associated with secondary neuronal shrinkage or loss, perhaps extending into related cortical gray matter.
Subclinical histopathological changes in the oculomotor nerve in diabetes mellitus
Authors: Smith Benn E. , Dyck Peter James 
Published: January 2005

AbstractTo provide reference values for the oculomotor nerve, for example, fascicular area and myelinated fiber (MF) number and size distribution, in pathological states, and to determine whether oculomotor nerves from diabetic patients without a history of oculomotor palsy have subclinical structural alterations, the morphometric features of 15 control subjects and eight diabetic patients were evaluated at a proximal and a distal level. On average the control nerves had a fascicular area of 2.7 mm2, 22,311 MF, and a bimodal diameter distribution with peaks at approximately 5 to 6 and 10 to 11 μm and a range of 2 to 20 μm. In proximal nerve, glial bundles were found in one‐half of the subjects and patients, with a peak of MF sizes that differed from fibers in nonglial areas. The nerves from diabetic patients departed from the nerves from control subjects in the following two respects: changed size distribution, suggesting atrophy of fibers, and microfasciculation of edge fibers in parts of the fascicles in one‐half of the patients. We conclude that glial bundles are probably a normal variant. Microfasciculation occurred much more frequently in nerves from diabetic patients and may represent subclinical injury of unknown cause. The alteration in size distribution may reflect the diabetic state and is not necessarily a precursor to diabetic ophthalmoplegia.
Nigral damage and dopaminergic hypofunction in mesencephalon‐immunized guinea pigs
Authors: Appel Stanley H. , Le Wei‐Dong , Tajti Janos , Haverkamp Lanny J. , Engelhardt Jozsef I. 
Published: January 2005

AbstractTo support a potential role for immune mechanisms in the destruction of substantia nigra (SN) neurons, guinea pigs were immunized with bovine mesencephalon containing SN neurons. After immunization no clinical signs of basal ganglia dysfunction appeared. However, pathological examination revealed evidence of neuronal damage in the SN in 8 of 17 guinea pigs immunized with bovine mesencephalon. No nigral pathology was noted in animals immunized with spinal cord gray matter or Freund's adjuvant alone. Accompanying the SN damage in mesencephalon‐immunized guinea pigs was a 25% decrease in tyrosine hydroxylase activity in the SN and a 27% decrease in dopamine content in the striatum. Deposits of IgG were detected by immunohistochemical techniques in sections of SN from mesencephalon‐immunized guinea pigs and in sections of human SN after exposure to serum from mesencephalon‐immunized guinea pigs. These data document the antigenicity of SN and suggest the possibility that immune mechanisms can contribute to basal ganglia pathology.
Decrease of D2 receptors indicated by 123I‐iodobenzamide single‐photon emission computed tomography relates to neurological deficit in treated Wilson's disease
Authors: Oertel W. H. , Tatsch K. , Schwarz J. , Kraft E. , Trenkwalder C. , Scherer J. , Weinzierl M. , Vogl T. , Kirsch C. M. 
Published: January 2005

AbstractSingle‐photon emission computed tomography with 123I‐iodobenzamide, a dopamine D2 receptor antagonist, was employed to study dopamine D2 receptor densities in 17 patients with biochemically proved Wilson's disease and stable neurological status with therapy and in 5 age‐matched control subjects. Of the 17 patients with Wilson's disease, 5 were neurologically asymptomatic, 3 had cerebellar signs, 1 exhibited a mild parkinsonian syndrome, 7 showed a parkinsonian syndrome and cerebellar signs, and 1 had generalized dystonia and a parkinsonian syndrome. In 5 age‐matched control subjects specific isotope binding as calculated by the basal ganglia to frontal cortex ratio was 1.57 ± 0.04 (mean ± standard deviation). The ratio in patients with Wilson's disease ranged from 1.56 ± 0.05 (n = 5, asymptomatic patients) to 1.17 ± 0.02 (n = 4, marked neurological impairment). We observed an almost linear correlation between the reduction of 123I‐iodobenzamide (IBZM) binding and the severity of neurological signs at the time of IBZM‐SPECT (correlation coefficient, −0.84; p < 0.01). We suggest that the reduction of postsynaptic striatal dopamine D2 receptors as detected by IBZM‐SPECT reflects striatal neuronal damage in Wilson's disease.
The free radical hypothesis in idiopathic parkinsonism: Evidence against it
Authors: Calne Donald B. 
Published: January 2005

AbstractThe free radical hypothesis for the pathogenesis of idiopathic parkinsonism (Parkinson's disease) has many similarities to the argument invoking an autoimmune mechanism. In both cases, cellular and molecular machinery that might be involved in neuronal destruction have been demonstrated. In recent years, the free radical hypothesis has become particularly fashionable; several workers have reported observations which, they infer, support the notion that damage by free radicals is a major factor in the underlying disease process. There is, however, no conclusive evidence that free radicals play a prominent role in the causal chain of events that leads to idiopathic parkinsonism; several findings may be construed as evidence against such a contention.
The oxidant stress hypothesis in Parkinson's disease: Evidence supporting it
Authors: Fahn Stanley , Cohen Gerald 
Published: January 2005

AbstractOxidant stress, due to the formation of hydrogen peroxide and oxygen‐derived free radicals, can cause cell damage due to chain reactions of membrane lipid peroxidation. Because the substantia nigra is rich in dopamine, which can undergo both enzymatic oxidation via monoamine oxidase and nonenzymatic autoxidation, hydrogen peroxide and oxyradicals (superoxide anion radical and hydroxyl radical) are generated in this midbrain nucleus. Although proof that oxidant stress actually causes the loss of monoaminergic neurons in patients with Parkinson's disease is lacking, there is a considerable body of evidence from studies in both animals and humans that support the concept. (1) Neurotoxins that selectively destroy the dopaminergic neurons in the nigra, such as 6‐hydroxydopamine and 1‐methyl‐4‐phenyl‐l,2,3,6‐tetrahydropyridine (MPTP), appear to act via oxidant stress. (2) The substantia nigra of patients with Parkinson's disease reveals evidence of oxidant stress by the findings of increased lipid peroxidation and decreased reduced glutathione. (3) Total iron is increased and ferritin is reduced in the substantia nigra pars compacta in patients with Parkinson's disease. This combination suggests that this transition metal is in a low molecular weight form, capable of catalyzing nonenzymatic oxidative reactions, especially the conversion of hydrogen peroxide to hydroxyl radical, which is the most reactive of the oxygen radicals. (4) Neuromelanin, a product of dopamine autoxidation, can serve as a reservoir for iron, promoting the generation of oxyradicals. (5) Antioxidant defense mechanisms appear to be reduced in the parkinsonian substantia nigra with the findings of decreased activities of glutathione peroxidase and catalase. (6) The recent findings of decreased activity of NADH‐CoQ reductase, a mitochondrial complex I enzyme, in substantia nigra and platelets in patients with Parkinson's disease can also be interpreted to be a cause or product of oxidant stress. The identical enzyme abnormality occurs with MPTP toxicity, and this has been associated with increased superoxide anion radical formation. Moreover, mice with increased activity of superoxide dismutase are protected against MPTP toxicity. The evidence favoring the oxidant stress hypothesis is persuasive, but not yet fully established. We believe that this is the best hypothesis available at present.
Lack of JC viral genomic sequences in multiple sclerosis brain tissue by polymerase chain reaction
Authors: Buckle Guy J. , Godec Mark S. , Rubi Jorge U. , Tornatore Carlo , Major Eugene O. , Gibbs Clarence J. , Gajdusek D. Carleton , Asher David M. 
Published: January 2005

AbstractWith DNA extracted from brain specimens from 19 multiple sclerosis, 5 progressive multifocal leukoencephalopathy, 1 Alzheimer's disease, and 8 nonneurological control subjects, polymerase chain reaction was performed using nested sets of primer pairs amplifying segments of the large T and VP1 antigen‐encoding sequences of JC virus. Both sequences were detected in each of the 5 brain specimens of progressive multifocal leukoencephalopathy but in none of the 19 multiple sclerosis, 1 Alzheimer's disease, or the 8 control brain specimens.
Correlation of myelin basic protein‐like material in cerebrospinal fluid of multiple sclerosis patients with their response to glucocorticoid treatment
Authors: Whitaker John N. , Layton Beverly A. , Herman Paula K. , Kachelhofer R. David , Burgard Sheila , Bartolucci Alfred A. 
Published: January 2005

AbstractPredictors and laboratory correlates of the response of patients with multiple sclerosis to glucocorticoids are not well defined. Our study was undertaken to determine if the levels of myelin basic protein (MBP)‐like material in cerebrospinal fluid (CSF) might indicate which patients with multiple sclerosis would show a short‐term (5 day) or intermediateterm (40 day) improvement of at least a full‐grade Kurtzke disability score after initiating treatment with glucocorticoids. A total of 62 patients received 71 courses of treatment consisting of 5 days of intravenous methylprednisolone (500 mg per day) usually followed by a 4‐week tapering dose of oral prednisone. CSF was obtained before initiation of treatment and analyzed for MBP‐like material by radioimmunoassay. Results were analyzed by χ2 tests of association and by logistic regression. Individuals having a CSF MBP‐like material level of ≥0.1 ng/ml overall showed a greater likelihood of continued improvement at day 40 (p = 0.014) or further improvement between days 5 and 40 (p = 0.003). Those in the first 15 days of worsening and with an elevated CSF MBP‐like level were more likely to respond by day 5. Relapsing–remitting and relapsing–progressive forms of the disease were more likely to respond at both time points than were patients with primary or secondary chronic progressive patterns. The Kurtzke disability score at entry and the major anatomical site of the central nervous system symptomatically affected were not predictive of outcome at either time. These studies indicate that the level of CSF MBP‐like material may help select those patients with multiple sclerosis who will show a response to short‐term glucocorticoid or other treatment.
Thyrotropin‐Releasing hormone gene expression and receptors are differentially modified in limbic foci by seizures
Authors: Kubek M. J. , Knoblach S. M. , Sharif N. A. , Burt D. R. , Buterbaugh G. G. , Fuson K. S. 
Published: January 2005

AbstractPrevious studies using two seizure paradigms, electronconvulsive shock and kindling, suggested potential sites of endogenous thyrotropin‐releasing hormone (TRH) action in specific epileptogenic areas. We studied TRH gene expression and TRH receptors in rat limbic areas using the kindling model of epilepsy. Immunoassayable TRH increased 4‐ to 20‐fold over control levels in specific subregions of the hippocampus 24 hours after a single stage 5 seizure. Concurrently, TRH receptor binding was significantly reduced in hippocampal (23–39%) and amygdaloid (21–22%) membranes. Dramatic temporal and spatial changes in prepro‐TRH messenger RNA were visualized by in situ hybridization histochemistry in the hippocampal dentate gyrus, the piriform cortex, and the amygdala. Peak hybridization occured 6 and 12 hours postictally in these loci and returned toward basal levels by 24 hours. These results are consistent with the hypothesis that TRH may have an important role in the pathophysiology of epilepsy by modulating excitatory processes.
Temporal neocortical role in ictal experiential phenomena
Authors: Blume Warren T. , Girvin John P. , Stenerson Paul 
Published: January 2005

AbstractResection of a left temporal neocortical tumor, preserving the amygdala and hippocampus, permanently abolished ictal illusions in a 20‐year‐old‐man, suggesting that neocortical epileptic discharge is essential in the production of the experiential phenomena of seizures. In light of other works demonstrating amygdala and hippocampal participation, we propose that ictal experiential phenomena represent simultaneous epileptic discharge of the temporal neocortex and the limbic system.
Spastic ataxia associated with human T‐cell lymphotrophic virus type II infection
Authors: Harrington William J. , Sheremata William , Hjelle Brain , Dube Dipak K. , Bradshaw Peggy , Foung Steven K. H. , Snodgrass Susan , Toedter Gary , Cabral Lisa , Poiesz Bernard 
Published: January 2005

AbstractHuman T‐cell lymphotropic virus type one (HTLV‐1) is associated with tropical spastic paraparesis or HTLV‐I‐associated myelopathy. We report 2 women with a spastic ataxic illness similar to HTLV‐I‐associated myelopathy infected solely with HTLV‐II. Identification of HTLV‐II infection was made serologically, by polymerase chain reaction, and by viral culture (in 1 woman). One woman, treated with 200 mg of danazol orally, three times daily, had pronounced improvement in ambulation, nocturnal spasticity, and nighttime urinary frequency. It appears that infection with HTLV‐II may cause an illness similar to HTLV‐I‐associated myelopathy, but distinguished by the presence of ataxia.
Dementia in Parkinson's disease: Biochemical evidence for cortical involvement using the immunodetection of abnormal tau proteins
Authors: Vermersch Patrick , Delacourte André , Javoy‐Agid France , Hauw Jean‐Jacques , Agid Yves 
Published: January 2005

AbstractIn order to elucidate the neurochemical basis of the dementia of Parkinson's disease, we compared samples of cerebral cortex from 24 nondemented parkinsonian patients and parkinsonian patients with various degrees of dementia, with those from patients with Alzheimer's disease and control subjects, using a quantitative Western blot analysis. An anti‐paired helical filaments antibody was used for the immunodetection of the abnormally phosphorylated Tau proteins 55,64, and 69, which are known to be specific and reliable biochemical markers of Alzaheimer‐type neurofibrillary degeneration. The frequency and intensity of immunodetection of the abnormal Tau triplet were higher in the demented parkinsonian subgroups than in the nondemented parkinsonian subgroup in the prefrontal area, temporal cortex, and entorhinal cortex but not in either the occipital or the cingular cortex. A quantification of abnormal Tau triplet by densaitometry showed that unlike the results obtained in Alzheimer patients, the intensity of lesions in the cerebral cortex of the most demented parkinsonian patients was more severe in the prefrontal area versus the temporal area. This study (1) gives biochemical evidence for Alzheimer‐type changes in the cortex of demented parkinsonian patients and (2) suggests that lesions of the prefrontal cortex may significantly contribute to the occurrence of cognitive changes at least in some patients with Parkinson's disease.