Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Both glial and neuronal cells maintained in primary culture were found to accumulate [3H]GABA by an efficient "high-affinity" uptake system (apparent Km = 9 muM, Vmax = 0.018 and 0.584 nmol/mg/min, respectively) which required sodium ions and was inhibited by 1 mM ouabain. Strychnine and parachloromercuriphenylsulfonate (pCS) (both at 1mM) also strongly inhibited uptake of [3H]GABA, but metabolic inhibitors (2,4-dinitrophenol, potassium cyanide, and malonate) were without effect. Only three structural analogs of GABA (nipecotate, beta-alanine, and 2,4-diaminobutyrate) inhibited uptake of [3H]GABA, while several other compounds with structural similarities to GABA (e.g. glycine, L-proline, and taurine) did not interact with the system. The kinetic studies indicated presence of a second uptake (Km = 92 muM, Vmax = 0.124 nmol/mg/min) in the primary cultures containing predominantly glioblasts. On the other hand, only one of the neuronal cell lines transformed by simian virus SV40 appeared to accumulate [3H]GABA against a concentration gradient. Apparent Km of this uptake was relatively high (819 muM), and it was only weakly inhibited by 1 mM ouabain and 1 mM pCS. The structural specificity also differed from that of the uptake observed in the primary cultures. Significantly, non of the nontransformed continuous cell lines of either tumoral (glioma, C6; neuroblastoma, M1; M1NN) or normal (NN;I6) origin actively accumulated [3H]GABA. It is suggested that for the neurochemical studies related to GABA and requiring homogeneous cell populations, the primary cultures offer a better experimental model than the continuous cell lines.
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PMID:High-affinity uptake of gamma-aminobutyric acid in cultured glial and neuronal cells. 22 77

The primary mechanism of cyanide (CN) intoxication is the inhibition of metabolism in the central nervous system. We determined the effects of CN on several biochemical processes in neuroblastoma x glioma hybrid NG108-15 cells, which possess numerous neuronal properties. These cells were not sensitive to a high concentration (1 mM) of NaCN, but became sensitive in the presence of the anaerobic glycolysis inhibitors sodium iodoacetate (IA) and 2-deoxyglucose (2-DG):cellular metabolic processes (e.g., DNA, RNA and protein synthesis) decreased to about 40% of control due to treatment with 0.5 mM NaCN + 0.05 mM IA and 0.1 mM NaCN + 20 mM 2-DG. ATP in cells exposed to 0.01 or 0.1 mM NaCN + 20 mM 2-DG was reduced 75% and 100% respectively within one min. Pretreatment of cells with the CN antidote cobalt (II) chloride (CoCl2) (0.06-0.18 mM) for 5 min prevented the depression of both [3H]leucine incorporation and ATP synthesis due to 1 mM NaCN + 20 mM 2-DG in a concentration-dependent manner. A proposed CN antidote alpha-ketoglutaric acid (disodium salt) also prevented the depression of cellular metabolism due to NaCN plus 2-DG. These results indicate that blocking anaerobic glycolysis makes NG108-15 cells sensitive to a low concentration of CN. Thus NG108-15 cells should be useful to study the mechanisms of neurotoxicity of CN and to test antidotes.
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PMID:Cyanide sensitive and insensitive bioenergetics in a clonal neuroblastoma x glioma hybrid cell line. 179 58

A technique is described which enables one to obtain detailed dose characteristics of 90Sr beta-ray ophthalmic applicators. A radiochromic radiation detector which is a solid-state solution of hexahydroxyethyl pararosaniline cyanide in a nylon polymer (i.e., thin foil), has been used to determine the surface dose rate and dose distribution of these sources. The detectors are rugged, easily handled, have an equivalent response (optical density per unit absorbed dose) to photons and electrons, and produce high-resolution images. They have been found useful for this application due to the high surface dose rates [0.10-1.0 Gy (H2O)/s] and their low sensitivity (approximately 10(4) Gy for an optical density of 1.0). The foils have been evaluated on a He-Ne scanning laser densitometer with a resolution of 0.3 mum. Comparison with NIST (formerly NBS) extrapolation ionization chamber measurements indicates surface dose-rate agreement within 6%. Spectral dosimetric characteristics are presented and discussed.
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PMID:A new method for characterizing beta-ray ophthalmic applicator sources. 187 Apr 89

An attempt was made to use neuroblastoma cells for testing neuroprotective drug effects. To achieve cellular damage, cytotoxic hypoxia was induced in neuroblastoma cells after 10 days in culture by addition of sodium cyanide (1 mmol/L) to the culture medium and was terminated after 6 hr by replacing the cyanide-containing fresh nutrient medium. During this hypoxic period cells were additionally deprived of glucose. They were allowed to recover for another 7 days. Drugs were available to the cells from 30 min prior to hypoxia until 24 hr after hypoxia. Cell concentration of high-energy phosphates and culture protein content were determined as representatives for the posthypoxic development of cell damage, cell activity and viability. While barbiturates and phenytoin revealed neurotoxic effects when applied in doses higher than 300 mumol/L, chlorpromazine, dizocilpine, ketamine, ketazocine, naftidrofuryl, and flunarizine protected neuroblastoma cells against hypoxic damage. These results were comparable to those obtained from primary cultures of neurons under similar experimental conditions. In addition, they were in keeping with neuroprotective drug effects obtained from in vivo experiments. It is suggested that neuroblastoma cells are suitable for testing neuroprotective drug effects.
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PMID:Neuroblastoma cells for testing neuroprotective drug effects. 194 24

The toxicity of single and multiple fire gases is studied to determine whether the toxic effects of the combustion products from materials can be explained by the toxicological interactions (as indicated by lethality) of the primary fire gases or if minor, more obscure gases need to be considered. LC50 values for Fischer-344 rats have been calculated for the individual gases, carbon monoxide (CO), hydrogen cyanide (HCN), or decreased oxygen (O2), for 30-min exposures plus relevant postexposure periods using the NBS Toxicity Test Method. Combination experiments with CO and HCN indicate that they act in an additive manner. Synergistic effects have been found when the animals are exposed to certain combinations of CO and carbon dioxide (CO2). Five percent CO2 raised the threshold for deaths due to hypoxia and decreased the LC50 of HCN. Decreasing the O2 concentration in the presence of various mixtures of the other major fire gases increased the toxicity even further. A comparison of the concentrations of the major combustion products generated from a number of polymeric materials at their LC50 (30-min exposure plus 14-day postexposure) values with the combined pure gas results indicates that, in most cases, the observed toxicity may be explained by the toxicological interactions of the examined primary toxic fire gases. These results provide necessary information for the computer model currently being developed at the Center for Fire Research to predict the toxic hazard that people will experience under various fire scenarios.
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PMID:Effects of exposure to single or multiple combinations of the predominant toxic gases and low oxygen atmospheres produced in fires. 282 Aug 22

Guanylate cyclase was activated 3- to 10-fold by hemin in a dose-dependent manner in membranes prepared from homogenates of rat lung, C6 rat glioma cells, or B103 rat neuroblastoma cells. Maximum activation was observed with 50 to 100 microM hemin with higher concentrations being inhibitory. Activation was observed when Mg2+-GTP but not when Mn2+-GTP was used as the substrate. Increased enzyme activity reflected selective activation of the particulate form of guanylate cyclase; hemin inhibited the soluble form of guanylate cyclase 70 to 90% over a wide range of concentrations. Activation was not secondary to proteolysis since a variety of protease inhibitors failed to alter stimulation by hemin. Protophorphyrin IX had little effect on particulate guanylate cyclase activity and sodium borohydride almost completely abolished hemin-dependent activation. These data suggest a requirement for the ferric form of the porphyrin-metal chelate for activation. However, agents which interact with the iron nucleus of porphyrins, such as cyanide, had little effect on the ability of hemin to activate guanylate cyclase. The stimulatory effects of hemin were observed in the presence of detergents such as Lubrol-PX, and highly purified particulate enzyme could be activated to the same extent as enzyme in native membranes. These data suggest that the interaction of porphyrins with particulate guanylate cyclase is complex in nature and different from that with the soluble enzyme.
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PMID:Selective activation of particulate guanylate cyclase by a specific class of porphyrins. 614 94

The neuroblastoma x glioma hybrid clone NG108-15 is able to release acetylcholine upon depolarization and form cholinergic neuromuscular synapses in culture. Normal functioning of cholinergic synapses is thought to be dependent on the ability of a neuron to take up extracellular choline, since neurons are unable to synthesize choline de novo. For these two reasons it became important to characterize the choline uptake system of NG108-15 cells. The uptake system appears to bear little if any resemblance to the Na+-dependent high-affinity choline uptake system normally associated with cholinergic neurons. Although the cells appear to possess both high- and low-affinity choline uptake systems, neither system is dependent on Na+ and uptake actually is increased about 60% by the substitution of sucrose for NaCl. Acetylcholine synthesis also is not dependent on Na+, since sucrose, substituted for NaCl, also stimulates acetylcholine synthesis. Changes in the concentrations of the other ions in the uptake medium have little effect on uptake, with the exception that elevated Ca2+ or Mg2+ reverses the stimulation of choline uptake produced by substitution of sucrose for NaCl. Choline uptake is inhibited by hemicholinium-3, but only at high concentrations of the drug (IC50 = 30-80 microM). The metabolic poisons cyanide and iodoacetate inhibit uptake by only 30-40%. Growth of the cells in N6,O2' dibutyryladenosine-3',5'-cyclic monophosphate, which promotes functional and morphological differentiation of the cells, decreased slightly the total amount of choline taken up but had no additional effect on the uptake system. Thus, it appears that NG108-15 cells are capable of forming functional cholinergic synapses with muscle cells even though the neuroblastoma does not possess the high-affinity choline uptake system normally associated with cholinergic neurons.
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PMID:Choline uptake by the neuroblastoma x glioma hybrid, NG108-15. 625 99

Morphological changes were extensive following infection of murine neuroblastoma N-18 cells with a temperature-sensitive (ts) mutant of vesicular stomatitis virus (VSV), G31 (complementation group III), and incubation at 39 degrees C, a non-permissive condition for virion maturation. Incubation for 24 h after infection resulted in extensive morphological degeneration of mitochondria with over 80% from that in uninfected cells. Janus green B supravital staining, was reduced by 81% from that in uninfected cells. Cellular ATP levels were reduced by 50% 12 h after infection. Mitochondrial degeneration still occurred in infected cells after the inactivation of lysosomes with chloroquine. Extensive cell fusion and cytoplasmic vacuole formation also occurred during the non-permissive infection with ts G31. Loss of plasma membrane integrity was not the cause of vacuole formation since 90% of the cells were able to exclude trypan blue 24 h after infection, nor were the vacuoles the result of inactivation of the mitochondria since cyanide-poisoned cells did not form vacuoles. The cytopathic alterations observed in N-18 cells during the non-permissive infection of N-18 cells with ts G31 did not occur during the non-permissive infection of N-18 cells with ts G11 (I), ts G41 (IV), or u.v.-inactivated ts G31. However, the non-permissive infection with ts O45 (V) led to mitochondrial degeneration and cytoplasmic vacuole formation, but no cell fusion occurred. These results are discussed in light of the ultrastructural features previously observed in the central nervous system of mice infected with ts G31 and cells in culture infected with wild-type VSV.
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PMID:Cytopathic effects in mouse neuroblastoma cells during a non-permissive infection with a mutant of vesicular stomatitis virus. 627 Feb 68

We report that 2,3-naphthalenedicarboxaldehyde reacts rapidly with glutathione and its precursor, gamma-glutamylcysteine, to form highly fluorescent derivatives under physiological conditions. In contrast to previous accounts of 2,3-naphthalenedicarboxaldehyde labeling of primary amines, no additional CN- ion or any other additional nucleophile is required. The fluorescence spectral properties of the chromophores (lambda exc max = 472 nm, lambda em max = 528 nm) make these derivatives amenable to excitation and detection by optical instrumentation that is optimized for fluorescein wavelengths. This selective labeling chemistry enabled quantitative determination and histochemical localization of glutathione in neurobiological samples. Intracellular glutathione was labeled by incubating cultured cells or cell suspensions in a 2,3-naphthalenedicarboxaldehyde-supplemented, DMSO-containing physiological buffer (pH = 7.4) for 2-10 min. Applications include imaging of cultured NG 108-15 cells (mouse neuroblastoma x rat glioma) and primary glial and neuronal cell cocultures (rat hippocampus) using epiluminescent and confocal fluorescence microscopy. Quantitative determination of glutathione in single NG 108-15 cells was accomplished using laser-induced fluorescence detection and capillary electrophoresis.
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PMID:Use of 2,3-naphthalenedicarboxaldehyde derivatization for single-cell analysis of glutathione by capillary electrophoresis and histochemical localization by fluorescence microscopy. 863 71

Sodium nitroprusside is widely used in pharmacological studies as a potent vasodilator or a nitric oxide donor. The mechanisms of cellular death induced by sodium nitroprusside were investigated in murine neuroblastoma N1E-115 cells. Sodium nitroprusside reduced the cellular viability, and the DNA extracted from treated cells showed a ladder-like intranucleosomal fragmentation pattern, which is an indication of apoptosis. The DNA fragmentations were also visualized by in situ nick translation. The cellular death was attenuated by cycloheximide, indicating that ongoing protein synthesis was essential for the initiation of the degenerative response. However, other nitric oxide donors did not decrease the cellular viability. The nitric oxide scavenger, hemoglobin, had no effect on sodium nitroprusside-induced cellular death. Furthermore, sodium cyanide, which is formed by the metabolism of sodium nitroprusside, did not cause cellular death. On the other hand, hydrogen peroxide, another product of sodium nitroprusside metabolism, reduced the cellular viability and induced DNA fragmentation. In addition, the cell damage induced by sodium nitroprusside was enhanced by a medium without fetal bovine serum. In conclusion, we proposed that hydrogen peroxide is the important toxic species for induction of apoptosis in N1E-115 cells exposed to sodium nitroprusside.
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PMID:Sodium nitroprusside-induced apoptotic cellular death via production of hydrogen peroxide in murine neuroblastoma N1E-115 cells. 864 75


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