Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The authors analyzed water-soluble proteins of culture human and rat glioma cells by two-dimensional polyacrylamide gel electrophoresis methods. Glioma cells were suspended in distilled water and then destroyed by freezing and thawing to obtain the water-soluble protein fraction. A modification of O'Farrell's non-equilibrium pH gradient (NEPHGE) method was used to analyze differences in protein mapping. Manabe's microscale two-dimensional electrophoresis without denaturing agents was used to detect proliferating cell nuclear antigen (PCNA/cyclin) by Western blotting. With O'Farrell's NEPHGE method and silver staining, at least 200 different polypeptides were clearly identified in each cell line. Cytoskeletal proteins, such as actin, were consistently separated in all cell lines. Marked differences in the protein map were observed between human and rat glioma cell lines, and even within the same species. Presumably, these differences are attributable to cell-biological difference in the glioma cells lines. Some proteins that were prominent in proliferating cells were scant in the protein maps of cells cultured for 24 hours in medium not containing calf serum, which suppresses cell growth. PCNA, an acidic nuclear protein that appears only in the late G1-S phase and is believed to be involved in cell proliferation, was detected by Western blotting and indirect immunostaining. Quantitative analysis of PCNA spots on the protein map appears useful in assessment of glioma cell proliferation. These results indicate that two-dimensional polyacrylamide gel electrophoresis can contribute to the understanding of the biological features of glioma cells.
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PMID:[Analysis of the water-soluble protein fraction of glioma cells by two-dimensional electrophoresis]. 247 47

Phosphoinositide and inositol metabolism was compared in glioma (C6), neuroblastoma (N1E-115) and neuroblastoma X glioma hybrid (NG 108-15) cells. All cell lines had similar proportions of phosphatidylinositol (PI), phosphatidylinositol 4-phosphate (PIP), and phosphatidylinositol 4,5-bisphosphate (PIP2). Neuroblastoma and hybrid cells had almost identical phospholipid and phosphoinositide compositions and similar activities for the enzymes metabolizing polyphosphoinositides (PI kinase, PIP phosphatase, PIP kinase, PIP2 phosphatase, PIP2 phosphodiesterase). Glioma cells differed by having greater proportions of ethanolamine plasmalogen and sphingomyelin, lower PIP kinase, 3-5-fold higher PIP phosphatase activity and 10-15-fold greater PIP2 phosphodiesterase activity. Higher PIP phosphatase and PIP2 diesterase activities appear to be characteristic of cells of glial origin, since similar activities were found in primary cultures of astroglia. Glioma cells also metabolize inositol differently. In pulse and pulse-chase experiments, glioma cells transported inositol into a much larger water-soluble intracellular pool and maintained a concentration gradient 30-times greater than neuroblastoma cells. Label in intracellular inositol was less than in phosphoinositides in neuroblastoma and exchanged rapidly with extracellular inositol. In glioma, labeling of intracellular inositol greatly exceeded that of phosphoinositides. As a consequence, radioactivity in prelabeled phosphoinositides could not be effectively chased from glioma cells by excess unlabeled inositol. Such differences between cells of neuronal and glial origin suggest different and possibly supportive roles for these two cell types in maintaining functions regulated through phosphoinositide-linked signalling systems in the central nervous system.
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PMID:Differences in the metabolism of inositol and phosphoinositides by cultured cells of neuronal and glial origin. 254 91

High-resolution 1H surface coil NMR spectroscopy (MRS) was used to evaluate in vivo the cerebral metabolism changes in rat brain induced by a glial tumor growing in situ. Tumor cells (C6 glioma cells) were stereotaxically placed in the right hemisphere superficially. 1H MRS was performed using 5-mm surface coils implanted over the right hemisphere and the water was suppressed using a binomial sequence. As the intracerebral tumor size increased, there was a marked decrease in the N-acetyl aspartate level and an increase in the 1.3 ppm peak. Edition of this peak showed that lactate increased but lipids increased much more than lactate. Moreover the ratio between the choline-phosphocholine and creatine-phosphocreatine peaks changed. This study demonstrates that high-resolution surface coil 1H MRS can be used to monitor changes in metabolism associated with growth of an experimentally induced rat brain tumor in situ.
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PMID:In vivo 1H NMR spectroscopy of an intracerebral glioma in the rat. 271 5

Gadolinium 1,4,7,10-tetraazacyclododecane-N,N',N",N"'-tetraacetic acid (Gd-DOTA) is the first of a new class of macrocyclic paramagnetic magnetic resonance (MR) contrast agents (gadolinium cryptelates) to be used in clinical practice. Gadolinium-DOTA possesses relaxation properties similar to those of gadolinium diethylene triamine pentaacetic acid (Gd-DTPA). We report our initial clinical experience in 38 patients with intracranial lesions studied with MR before and after injection of Gd-DOTA. Diseases included primary and metastatic brain tumor, cerebral infarct, vascular malformation, meningioma, hemangiopericytoma, schwannoma, and pituitary macroadenoma. Gadolinium-DOTA was administered intravenously in a dosage of 0.1 mmol/kg body weight. All studies were performed on a superconductive 0.5 T system. As compared to noncontrast T1- and T2-weighted images (WI), Gd-DOTA enhanced T1 WI were useful in defining the anatomy of malignant intraaxial tumors (high-grade glioma, metastasis) and in tumor versus edema differentiation. Low-grade gliomas did not enhance; in these cases the precontrast T2-weighted sequence was found to be more informative. In post-operative patients, Gd-DOTA allowed us to demonstrate residual tumor or tumor recurrence. Extraaxial tumors (meningioma, hemangiopericytoma, neuroma) enhanced markedly, presumably reflecting tumor vascularity. In our experience, the use of Gd-DOTA improves the anatomic definition of cerebral lesions and in some cases increases both MR sensitivity and specificity. We found Gd-DOTA to be a well tolerated and effective paramagnetic contrast agent. Gadolinium-DOTA can be considered as an alternative water-soluble MR contrast agent to Gd-DTPA.
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PMID:Gadolinium-DOTA enhanced MR imaging of intracranial lesions. 272 66

In adult cats experimental brain tumours were produced by stereotactical xenotransplantation of the rat glioma clone F 98 into the internal capsule of the left hemisphere. Two to four weeks after transplantation tumours and peritumoural oedema were investigated by magnetic resonance imaging (MRI), electrophysiological recording and analysis of tissue content of water, electrolytes and extravasated serum proteins. Spherical tumours with a diameter of about 10 mm developed at the injection site and were surrounded by massive white matter oedema. Water content in peritumoural white matter increased from 2.63 +/- 0.17 to 3.65 +/- 0.19 ml/g d.w. (means +/- SD), sodium from 187 +/- 11 to 351 +/- 55 mueq/g d.w. and calcium from 7.4 +/- 1.1 to 13.3 +/- 1.3 +/- 1.3 mueq/g d.w. Potassium and magnesium did not change. Oedema development was associated with the extravasation of 18.0 +/- 16.8 mg/g d.w. albumin and 15.8 +/- 12.2 mg/g d.w. immunoglobulin. The calculated electrolyte content of oedema fluid approximated that of plasma but the serum protein content was about 40% lower. The ratio of low (albumin) to high (immunoglobulin) molecular weight proteins was the same in blood and oedema fluid. It is, therefore, concluded that peritumoural oedema consist of two components, a whole plasma extravasate and a protein-free ultrafiltrate. Peritumoural oedema could be clearly detected by MRI but differentiation between tumour and oedema was only possible after contrast enhancement with gadolinium-DTPA. The ratios of the intensities of the MR signal correlated linearly with the water content within white matter. MRI, in consequence, allows quantification of oedema provided a reference area with normal water content is present.
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PMID:Experimental transplantation gliomas in the adult cat brain. 2. Pathophysiology and magnetic resonance imaging. 274 48

The presence of a brain tumor alters regional cerebral blood flow, oxygen consumption, and glucose utilization in adjacent and remote brain tissue, but its effect on brain neurotransmitter levels is unclear. In the present report, the levels of noradrenaline (NA), dopamine (DA), 5-hydroxytryptamine (5-HT), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), and 5-hydroxyindoleacetic acid (5-HIAA) in tumor tissue and gray and white matter obtained from cats with induced brain tumors were measured. Glioma cells (9L) were xenotransplanted into the central white matter of the right hemisphere, and 15 d later the brains were frozen in vivo. Samples of tumor, parietal (peritumor), temporal, and frontal gray and white matter were divided for analysis of water content and quantification of amines and their metabolites. The water content of white matter, but not gray matter, adjacent to the tumor was increased. Neurotransmitter amine and metabolite levels were much lower in the tumor than in brain tissue. In gray matter adjacent to the tumor, concentrations of DA and its metabolites HVA and DOPAC were significantly decreased from control, whereas 5-HIAA was increased. The NA, DA, HVA, and DOPAC levels were decreased in temporal gray matter, whereas all amine and metabolite levels were unchanged in frontal gray matter. These results indicate that altered neurotransmitter metabolism is one of the effects of the presence of a brain tumor.
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PMID:Regional monoamine and metabolite levels in a feline brain tumor model. 274 38

Experimental brain tumours were produced in adult cats by stereotactic xenotransplantation of the rat glioma clone F98. Regional ATP, glucose and lactate were measured after 2-4 weeks on coronal cryostat sections by substrate-induced bioluminescence, potassium content was imaged by the histochemical sodium cobaltinitrite method, and regional pH by incubating cryostat sections with the fluorescent pH-indicator umbelliferone. The regional biochemical alterations were correlated with magnetic resonance imaging and tissue water content. Biochemical changes were heterogeneous in tumours but exhibited a rather uniform pattern in peritumoural oedema. ATP was consistently reduced, glucose and lactate were increased and pH was more alkaline than in normal white matter. The decrease of ATP matched the increase of water, indicating that ATP decline represents fractional dilution in the oedematous tissue rather than break-down of energy metabolism. The increased lactate levels, therefore, may originate from the tumour and not from a metabolic disturbance in the peritumoural oedematous tissue. The implications of this interpretation for the pathogenesis of peritumoural oedema are discussed.
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PMID:Experimental transplantation gliomas in the adult cat brain. 3. Regional biochemistry. 275 53

Hyponatremia, in patients with central nervous system disease, can be attributable to impaired free water excretion (syndrome of inappropriate secretion of antidiuretic hormone) or to excessive sodium excretion (cerebral salt wasting). We present a patient with a parietal glioma and hyponatremia characterized by salt wasting and dehydration. Rehydration and sodium repletion corrected the sodium and volume deficits; withdrawal of supplemental sodium resulted in recurrence of dehydration and hyponatremia. We determined sodium and water balance and measured plasma atriopeptin, antidiuretic hormone, and aldosterone. Plasma atriopeptin ranged from 8 to 44 pg/mL (normal, less than 45 pg/mL); antidiuretic hormone was not elevated at 4 to 5 pg/mL, and aldosterone was slightly elevated at 1040.25 pmol/L. The concentrations of these hormones could not directly explain the natriuresis; interactions with neural or other humoral factors may be involved. In evaluating such patients, careful attention to sodium and water balance is important to guide appropriate therapy.
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PMID:Sodium and water regulation in a patient with cerebral salt wasting. 275 34

The major pathway of choline (Cho) incorporation into phosphatidylcholine (PtdCho) in mammalian cells is sequential conversion of Cho to phosphocholine (PCho), cytidinediphosphate choline (CDP-Cho) and PtdCho. In intact cells, this sequence is usually demonstrated using radiolabeled Cho since PCho and CDP-Cho do not enter the cell intact. We have studied the incorporation of radiolabeled Cho, PCho and CDP-Cho into rat glioma (C6) cells following electropermeabilization. C6 cells were permeable as judged by [U-14C]sucrose and Erythrosin B uptake and more rapid incorporation of [1,2,3-3H]glycerol into cell lipids, and viable as assessed by uptake and incorporation of [methyl-3H]Cho, [1-14C]oleate and [1,2,3-3H]glycerol into complex lipids. Despite rapid incorporation of [methyl-3H]Cho into PtdCho in permeabilized cells, there was no incorporation of [methyl-14C]PCho or CDP-[methyl-14C]Cho into PtdCho. PCho (300 microM) and CDP-Cho (300 microM) failed to significantly reduce incorporation of 28 microM [methyl-3H]Cho into PtdCho. Radioactivity in PtdCho of cells prelabeled with [methyl-3H]Cho prior to permeabilization could be chased with 4 mM Cho but not with 4 mM PCho or 4 mM CDP-Cho. The water-soluble products of Cho metabolism--PCho, CDP-Cho and glycerophosphocholine--were retained at 37 degrees C in permeabilized cells compared with controls while there was uniform leakage from permeabilized cells at 4 degrees C. Hemicholinium-3, an inhibitor of high-affinity Cho transport, decreased [methyl-3H]Cho incorporation into PtdCho in permeabilized cells, as in controls, suggesting that even in permeabilized cells, Cho incorporation into PtdCho is linked to the transport system. We propose that individual steps of the cytidine pathway of PtdCho biosynthesis are functionally linked and that reaction intermediates are not freely diffusible within the cell but are channeled to PtdCho biosynthesis.
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PMID:Phosphatidylcholine biosynthesis in cultured glioma cells: evidence for channeling of intermediates. 275 24

Lead has been demonstrated to induce precocious glial differentiation both in vitro and in vivo. Lead-treated rat glioma (C6) and cerebellar astrocytes exhibited cytoplasmic extensions and the presence of glial endfeet after a 3-day exposure to 10(-6) to 10(-4) M PbCl2. In similar experiments no effect was noted in neuroblastoma (Neuro-2a) or on neurite outgrowth from chick spinal cord explants. This prodifferentiative effect on glia was also seen in the cerebella of postnatal rats in which the developmental expression of glial-specific glutamine synthetase activity was significantly increased up to postnatal day 12 after chronic exposure to lead from time of birth via their dam's drinking water (400 mg PbCl2/l).
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PMID:Chronic low level lead exposure precociously induces rat glial development in vitro and in vivo. 289 24


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