Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036572 (seizures)
 80,221 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A case of chordoid meningioma occurring in a 15-year-old girl is presented. The patient manifested seizures as the initial symptom and subsequently exhibited subclinical microcytic hypochromic anemia. The tumor, located in the falcotentorial region and associated with diffuse edema, was totally resected. On histological examination of the surgical specimen, the clustering pattern of partly vacuolated cells in the mucoid stroma mimicked chordoma; however, positive staining of individual cells for vimentin and epithelial membrane antigen led to a diagnosis of meningioma. Interestingly, the tumor cells were surrounded by a periodic acid-Schiff- and type IV collagen-positive substance. Electron microscopy demonstrated a strikingly dense and thick basal lamina. The patient's microcytic hypochromic anemia disappeared after the tumor was removed. Both the clinical and pathological features of this case resemble those of chordoid meningioma, a rare meningioma variant.
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PMID:Chordoid meningioma in a child. Case report. 976 Oct 71

Glial cells are believed to play a major role in the regulation of the extracellular potassium concentration ([K+]o), particularly when the [K+]o is increased. Using ion-selective electrodes, we compared the [K+]o changes in the dentate gyrus of urethane-anaesthetized adult rats in the presence of reactive astrocytes and after reduction of glial function. The regulation of [K+]o in the dentate gyrus was determined by measuring the ceiling level of [K+]o and the half-time of recovery of [K+]o during and after seizures produced by 20 Hz trains of stimulation to the angular bundle. Reactive astrocytes were induced by repeated seizures and their presence was confirmed by a qualitative increase in glial fibrillary acidic protein (GFAP) and vimentin immunoreactivity. To inhibit glial function, fluorocitrate (FC), a reversible metabolic inhibitor, or alpha-aminoadipate (alpha-AA), an irreversible toxin, was injected into the dentate gyrus region, and the regulation of [K+]o was monitored for 8 h or 2 days later, respectively. After alpha-aminoadipate, loss of astrocytes in the dentate gyrus was demonstrated by loss of staining for GFAP. In the presence of reactive astrocytes there was no significant change in the peak [K+]o during seizures or the half-time of recovery of [K+]o after seizures compared to control animals. alpha-Aminoadipate significantly slowed the rate of recovery of [K+]o, but did not change the ceiling [K+]o. Fluorocitrate reversibly decreased the ceiling [K+]o, but also slowed the rate of recovery of [K+]o. Overall our results suggest that normal glial function is required for the recovery of elevated [K+]o after seizures in vivo.
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PMID:Astrocytic regulation of the recovery of extracellular potassium after seizures in vivo. 1021 21

In this study we investigated the time course, cell-type and stress-specific expression of hsp70 mRNA and Hsp70 protein in glial cells and neurons in the rat brain following heat shock treatment and kainic acid-induced status epilepticus. Transcripts for hsp70 were detected in hippocampal homogenates from 1.5 to 6 h following hyperthermia and from 3 to 24 h following kainic acid-induced seizures. In situ hybridization revealed hsp70 mRNA to be region specific and time-dependent following hyperthermia and kainic acid-induced seizures. Western analysis indicated that Hsp70 reached maximal levels at 3 h after hyperthermia and 12 h after kainic acid-induced seizures. Immunohistochemistry revealed low level expression of Hsp70 protein in dentate granule cells at 1.5 and 3 h after hyperthermia. No Hsp70 protein was detected in neurons of the pyramidal cell layer or dentate hilus at any time following hyperthermia. Small Hsp70-immunoreactive cells were detected throughout the hippocampus following hyperthermia that, based on cell size, distribution, and double-labeling with vimentin, were considered to be glia. In contrast, high levels of Hsp70 protein were detected in neurons of the pyramidal cell layer and dentate hilus at 24 h after seizure-inducing kainic acid injection. These results suggest that expression of Hsp70 protein is cell-specific depending on the stressor. In addition, finding high levels of Hsp70 mRNA in the dentate granule cells after hyperthermia, but little or no Hsp70 protein, suggests that the synthesis of the protein is also regulated at the post-transcriptional level following hyperthermia.
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PMID:Cell specific expression of Hsp70 in neurons and glia of the rat hippocampus after hyperthermia and kainic acid-induced seizure activity. 1052 81

We describe efficient methods for using functional proteomics analysis to study signal transduction pathways in murine fibroblast L929 cells following stimulation with tumor necrosis factor (TNF)-alpha. After stimulation with TNF-alpha, cellular proteins of L929 cells were extracted with a lysis buffer containing 0.3% sodium dodecyl sulfate (SDS) for 10-30 min time intervals, and were separated by two-dimensional (2-D) electrophoresis followed by immunoblot analysis with anti-phosphotyrosine antibody and alkaline phosphatase-anti IgG antibody conjugate. To improve detection sensitivity by immunoblot analysis we used a chemifluorescent substrate for alkaline phosphatase. One hundred protein spots were detected in the TNF-alpha stimulated L929 cell extract by immunoblot analysis. The use of chemifluorescence allowed us to quantitate immunoblotted spots with fluoroscanner so that we were able to detect time-dependent changes of a number of immunoblotted spots. Protein spots on a silver-stained 2-D gel corresponding to those detected by immunoblot analysis were subjected to in-gel trypsin digestion- matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF)-mass spectrometry analysis, respectively. Twenty-one proteins detected by immunoblot analysis were identified by MS-Fit database search analysis. Among them, the proteins that show time-dependent changes in staining intensity include vimentin, tubulin beta-chain, eukaryotic translation initiation factor 1A, chromatin assembly factor 1 (P48 subunit), probable protein disulfide isomerase P5, and several other proteins. Vimentin and tubulin beta-chain have been reported to be phosphorylated at tyrosine residues and involved in the signal transduction pathway induced by TNF-alpha. However, the other proteins have no previously known function in the signal transduction pathway. Thus, the methods used in this study seem to be suitable for the identification of time-dependent changes in many proteins that are involved in signal transduction. Usefulness of the method for comprehensive analysis of the proteins involved in signal transduction pathway and the limitations of the method are discussed.
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PMID:Matrix assisted laser desorption/ionization-time of flight-mass spectrometry analysis of proteins detected by anti-phosphotyrosine antibody on two-dimensional-gels of fibrolast cell lysates after tumor necrosis factor-alpha stimulation. 1087 Sep 74

Reactive gliosis is a prominent morphological feature of mesial temporal lobe epilepsy. Because astrocytes express glutamate receptors, we examined changes in metabotropic glutamate receptor (mGluR) 2/3, mGluR5 and transforming growth factor (TGF)-beta in glial cells of the hippocampal regions in an experimental rat model of spontaneous seizures. Rats that exhibited behavioural status epilepticus (SE) directly after 1 h of electrical angular bundle stimulation, displayed chronic spontaneous seizures after a latent period of 1-2 weeks as observed using continuous electrographic monitoring. SE resulted in hypertrophy of astrocytes and microglia activation throughout the hippocampus as revealed by immunolabelling studies. A dramatic, seizure intensity-dependent increase in vimentin immunoreactivity (a marker for reactive astrocytes) was revealed in CA3 and hilar regions where prominent neuronal loss occurs. Increased vimentin labelling was first apparent 24 h after onset of SE and persisted up to 3 months. mGluR2/3 and mGluR5 protein expression increased markedly in glial cells of CA3 and hilus by 1 week after SE, and persisted up to 3 months after SE. Double immunolabelling of brain sections with vimentin confirmed co-localization with glial fibrillary acidic protein (GFAP), mGluR2/3 and mGluR5 in reactive astrocytes. TGF-beta, a cytokine implicated in mGluR3-mediated neuroprotection, was also upregulated during the first 3 weeks after SE throughout the hippocampus. This study demonstrates seizure-induced upregulation of two mGluR subtypes in reactive astrocytes, which - together with the increased production of TGF-beta - may represent a novel mechanism for modulation of glial function and for changes in glial-neuronal communication in the course of epileptogenesis.
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PMID:Upregulation of metabotropic glutamate receptor subtype mGluR3 and mGluR5 in reactive astrocytes in a rat model of mesial temporal lobe epilepsy. 1094 12

A granular cell tumor involving the pituitary gland, optic chiasm and ventral pyriform lobes was discovered in a 12-year-old Labrador Retriever. Clinical signs included acute blindness, seizures, ataxia, weakness, and behavioral changes. The diagnosis was established by histopathologic and ultrastructural examination of neoplastic tissues collected at necropsy. Granular cell tumors involving the central nervous system are well documented in humans but rarely have been described in dogs. The location of the neoplasm and the clinical symptoms seen in this dog closely parallel those of a rare syndrome in humans commonly described as symptomatic parasellar or pituitary granular cell tumors. The cell of origin for these tumors is still highly debated, and attempts to characterize human granular cell tumors through immunohistochemistry have produced conflicting results. An immunohistochemical profile of this neoplasm revealed focal positive staining for vimentin with a lack of staining for neuron-specific enolase, glial fibrillary acidic protein, S-100, and synaptophysin. All neoplastic cells were strongly positive with the periodic acid-Schiff reaction.
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PMID:Symptomatic granular cell tumor involving the pituitary gland in a dog: a case report and review of the literature. 1135 66

Choroid plexus carcinomas in four dogs (three male, one female) aged small middle 2.5 to 10 years, were examined by light microscopy and immunohistochemistry. The dogs showed progressive neurological signs including ataxia, seizures, vestibular disease and cranial nerve deficits, lasting for several months in some cases. Primary tumours were localized in the lateral (one case), third (one case), and fourth (two cases) ventricles. Hydrocephalus was evident at post-mortem examination in one case. In two cases the neoplastic cells closely resembled the structure of normal choroid plexus, with a distinct papillary pattern, composed of well-differentiated columnar epithelium. In the other two cases, cellular pleomorphism, nuclear atypia, increased mitotic activity and necrosis were observed. In all cases, dissemination of neoplastic cell clusters was detected within the subarachnoid space or the ventricular cavity. Immunohistochemical examination showed a multifocal labelling pattern for pankeratin and cytokeratin AE1 and diffuse vimentin positivity in poorly differentiated tumours. Well-differentiated choroid plexus carcinomas showed multifocal immunoreactivity for cytokeratin AE3, multifocal to diffuse immunoreactivity for vimentin and occasional positivity for carcinoembryonic antigen. Epithelial membrane antigen, Ber EP4 and S-100 were negative in all cases. Glial fibrillary acidic protein labelling occurred only in a single, poorly differentiated tumour. Occasional reactions for proliferating cell nuclear antigen and MIB-1 were seen in two cases. It was concluded that at least two morphological and possibly phenotypic subtypes (well-differentiated and anaplastic) of choroid plexus carcinoma of the dog could be identified.
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PMID:Pathological and immunohistochemical studies of choroid plexus carcinoma of the dog. 1194 7

Benign fibrous histiocytomas (BFHs) are tumors with fibroblastic and histiocytic components without histological anaplasia. Intracerebral lesions are exceptional and to our knowledge a spinal location was not yet described. We describe 2 cases of BFHs of the neural axis: the first, a 22-month-old boy with Down's syndrome, presented with a paraparesis and the magnetic resonance (MR) of the spine disclosed an intradural extramedullary, thoracic mass, totally resected; the second, a 13-year-old boy with left partial motor seizures, in whom the MR of the brain showed an intracerebral, right frontal tumor, also surgically removed. Both patients are free of recurrence, 6 years and 15 months after surgery, respectively. Histological examination and immunoreactivity for vimentin and histiocytic markers favored the diagnosis of BFH. It is likely that these tumors may originate from spinal dura mater mesenchymal stem cells and from the intracerebral perivascular pial sheath or the brain vessel walls themselves, respectively. Other benign, isolated, intracranial fibrohistiocytic neoplasms, namely the juvenile xanthogranuloma, can harbor a clinical, morphological and immunohistochemical profile overlapping the one of the BFH. Intracranial germ cell tumors may be associated with Down's syndrome, although harboring an unusual, non-pineal and non-chiasmatic location. One can speculate that a similar, still unknown genetic mechanism responsible for this association, could also induce the growth of other type of tumors in patients with this syndrome. BFHs should be added to the differential diagnosis of intracerebral or spinal dural attached tumors. Furthermore, we propose to name these intracranial tumors "benign isolated fibrohistiocytic tumors of the CNS".
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PMID:Benign isolated fibrohistiocytic tumor arising from the central nervous system. Considerations about two cases. 1204 82

In human temporal lobe epilepsy, a dispersion of dentate granule cells is frequently described in adults who had an early risk factor. To elucidate the role of glia in this phenomenon, we investigated neuronal dispersion, astrocyte organization and expression of intermediate filaments of mature and immature astrocytes (i.e. glial fibrillary acidic protein (GFAP) and vimentin, respectively) in seven subjects with early febrile seizures (F(+)) and five subjects with other etiologies than febrile seizures (F(-)). Compared to F(-) patients, a majority of F(+) subjects showed neuronal dispersion and vimentin expression in radial glia. However, in two patients with the maximal dispersion, radial processes expressed only GFAP. We suggest that granule cell migration that occurs in adult epileptic focus results from the transient occurrence of immature-like glia throughout the granular layer.
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PMID:Immature-like astrocytes are associated with dentate granule cell migration in human temporal lobe epilepsy. 1221 46

Complex partial epilepsy is a seizure disorder in which attacks frequently arise from foci located in the temporal lobes. The amygdala-kindling model is a widely used model of complex partial epilepsy with secondary generalization. The present study was designed to quantitatively assess astrocytic changes in the rat piriform cortex in the amygdala-kindling model of epilepsy. Bromodeoxyuridine-injected subjects were sacrificed 24 h after the first stage 1 or fifth stage 5 seizure. Brain sections were prepared and examined quantitatively. A significantly higher number of dividing astrocytes (identified by co-labeling with antibodies to bromodeoxyuridine and to one of the astrocytic intermediate filament proteins glial fibrillary acidic protein or vimentin) was found in both partially kindled (stage 1) and fully kindled (stage 5) brains. The partially kindled brains had a significantly higher number of double-labeled cells on the side ipsilateral to stimulation. The opposite trend was observed in the fully kindled brains. Differences between the ipsilateral and contralateral sides of the kindled brain may suggest different role(s) for astrocytes in the development and progression of the seizure-prone state.
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PMID:Astrocytic proliferation in the piriform cortex of amygdala-kindled subjects: a quantitative study in partial versus fully kindled brains. 1535 12


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