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)

Children are exposed to potentially carcinogenic pesticides from use in homes, schools, other buildings, lawns and gardens, through food and contaminated drinking water, from agricultural application drift, overspray, or off-gassing, and from carry-home exposure of parents occupationally exposed to pesticides. Parental exposure during the child's gestation or even preconception may also be important. Malignancies linked to pesticides in case reports or case-control studies include leukemia, neuroblastoma, Wilms' tumor, soft-tissue sarcoma, Ewing's sarcoma, non-Hodgkin's lymphoma, and cancers of the brain, colorectum, and testes. Although these studies have been limited by nonspecific pesticide exposure information, small numbers of exposed subjects, and the potential for case-response bias, it is noteworthy that many of the reported increased risks are of greater magnitude than those observed in studies of pesticide-exposed adults, suggesting that children may be particularly sensitive to the carcinogenic effects of pesticides. Future research should include improved exposure assessment, evaluation of risk by age at exposure, and investigation of possible genetic-environment interactions. There is potential to prevent at least some childhood cancer by reducing or eliminating pesticide exposure.
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PMID:Pesticides and childhood cancer. 964 54

The possible role of Ca2+ as a second messenger mediating regulatory volume decrease (RVD) in osmotically swollen cells was investigated in murine neural cell lines (N1E-115 and NG108-15) by means of novel microspectrofluorimetric techniques that allow simultaneous measurement of changes in cell water volume and [Ca2+]i in single cells loaded with fura-2. [Ca2+]i was measured ratiometrically, whereas the volume change was determined at the intracellular isosbestic wavelength (358 nm). Independent volume measurements were done using calcein, a fluorescent probe insensitive to intracellular ions. When challenged with approximately 40% hyposmotic solutions, the cells expanded osmometrically and then underwent RVD. Concomitant with the volume response, there was a transient increase in [Ca2+]i, whose onset preceded RVD. For hyposmotic solutions (up to approximately -40%), [Ca2+]i increased steeply with the reciprocal of the external osmotic pressure and with the cell volume. Chelation of external and internal Ca2+, with EGTA and 1,2-bis-(o -aminophenoxy) ethane-N,N,N ',N '-tetraacetic acid (BAPTA), respectively, attenuated but did not prevent RVD. This Ca2+-independent RVD proceeded even when there was a concomitant decrease in [Ca2+]i below resting levels. Similar results were obtained in cells loaded with calcein. For cells not treated with BAPTA, restoration of external Ca2+ during the relaxation of RVD elicited by Ca2+-free hyposmotic solutions produced an increase in [Ca2+]i without affecting the rate or extent of the responses. RVD and the increase in [Ca2+]i were blocked or attenuated upon the second of two approximately 40% hyposmotic challenges applied at an interval of 30-60 min. The inactivation persisted in Ca2+-free solutions. Hence, our simultaneous measurements of intracellular Ca2+ and volume in single neuroblastoma cells directly demonstrate that an increase in intracellular Ca2+ is not necessary for triggering RVD or its inactivation. The attenuation of RVD after Ca2+ chelation could occur through secondary effects or could indicate that Ca2+ is required for optimal RVD responses.
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PMID:Regulatory volume decrease and intracellular Ca2+ in murine neuroblastoma cells studied with fluorescent probes. 968 24

The importance of determining the N-Myc protein has been emphasized in neuroblastoma. We attempted to obtain a water-soluble N-Myc protein, and an antibody highly specific for the N-Myc protein. A plasmid was constructed from partial exons 2 and 3 of the N-myc gene, and expressed in Escherichia coli by isopropyl-beta,-D-thiogalactopyranoside. Newly obtained N-Myc (rN-Myc) was water-soluble with a M.W. of 38 kDa. An N-Myc-specific peptide, GVAPPRPGG RQTSGGDH, was used to raise an antibody. Specificity of the obtained antibody was confirmed and we found the rN-Myc protein reacts positively with the anti-N-Myc IgG raised here. The rN-Myc protein and the anti-N-Myc IgG obtained are expected to be used in an ELISA for N-Myc.
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PMID:A polyclonal antibody against synthetic peptide conserved in N-Myc protein reacts with water-soluble recombinant N-Myc protein. 986 11

Volumes of neuroblastoma x glioma hybrid NG 108-15 cells were electronically measured in order to characterize the mechanisms involved in volume regulation in isosmotic and anisosmotic conditions. The cells behave as perfect osmometers when tonicity was changed at constant chloride concentration by adding sucrose or replacing NaCl with CaCl2 or MgCl2. In contrast, the cell volume was poorly dependent on tonicity when the Cl- concentration was changed by adding NaCl or H2O. Cell shrinkage was induced by cell stirring or after a hypotonicity-induced swelling. These volume decreases were abolished by caffeine but not by ryanodine or EGTA. Shrinkage was also induced by the Ca2+ ionophore ionomycin. The ionomycin-induced volume decrease was abolished by EGTA. Cell swelling induced an outwardly rectifying Cl- current which was blocked by 5-nitro-2-(3-phenylpropylamino)benzoic acid, 4,4'-diisothiocyanatostilbene-2,2'-disulphonic acid and dihydroindenyloxy-alkanoic acid. When the tonicity was reduced at constant Cl- concentration by replacing NaCl with CaCl2 or MgCl2, the volume increased and then slowly decreased towards its control value. This regulatory volume decrease was blocked by 5-nitro-2-(3-phenylpropylamino)benzoic acid, 4,4'-diisothiocyanatostilbene-2,2'-disulphonic acid and dihydroindenyl-oxy-alkanoic acid. Long-term (hours-days) cell shrinkage was induced by a reduction of the culture medium osmolarity. Long-term cell swelling was induced by an increase of the culture medium osmolarity. These volume changes were abolished by the protein translation inhibitor cycloheximide. The results suggest that NG 108-15 cell volume is regulated by at least four interacting mechanisms controlled, respectively, by intracellular Ca2+, extracellular NaCl, cell volume and intracellular ionic strength. The speculative nature of ionic systems responsible for these volume regulating mechanisms is discussed.
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PMID:Evidence for several mechanisms of volume regulation in neuroblastoma x glioma hybrid NG108-15 cells. 1005 Dec 9

High-dose busulphan-containing chemotherapy regimens have shown high response rates in children with relapsed or refractory neuroblastoma, Ewing's sarcoma and medulloblastoma. However, the anti-tumour activity of busulfan as a single agent remains to be defined, and this was evaluated in athymic mice bearing advanced stage subcutaneous paediatric solid tumour xenografts. Because busulphan is highly insoluble in water, the use of several vehicles for enteral and parenteral administration was first investigated in terms of pharmacokinetics and toxicity. The highest bioavailability was obtained with busulphan in DMSO administered i.p. When busulphan was suspended in carboxymethylcellulose and given orally or i.p., the bioavailability was poor. Then, in the therapeutic experiments, busulphan in DMSO was administered i.p. on days 0 and 4. At the maximum tolerated total dose (50 mg kg(-1)), busulphan induced a significant tumour growth delay, ranging from 12 to 34 days in the three neuroblastomas evaluated and in one out of three medulloblastomas. At a dose level above the maximum tolerated dose, busulphan induced complete and partial tumour regressions. Busulphan was inactive in a peripheral primitive neuroectodermal tumour (PNET) xenograft. When busulphan pharmacokinetics in mice and humans were considered, the estimated systemic exposure at the therapeutically active dose in mice (113 microg h ml(-1)) was close to the mean total systemic exposure in children receiving high-dose busulphan (102.4 microg h ml(-1)). In conclusion, busulphan displayed a significant anti-tumour activity in neuroblastoma and medulloblastoma xenografts at plasma drug concentrations which can be achieved clinically in children receiving high-dose busulphan-containing regimens.
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PMID:Busulphan is active against neuroblastoma and medulloblastoma xenografts in athymic mice at clinically achievable plasma drug concentrations. 1007 Aug 70

Aphidicolin is a fungal derived tetracyclic diterpene antibiotic. It is selectively toxic for neuroblastoma (NB) cells in vitro but has no significant effects on the viability of normal human cells and a variety of other tumor entities. We evaluated the antitumoral effects of the water soluble ester aphidicolin glycinate (AphiG) on established human NB xenografts from UKF-NB-3 cells in athymic (nude) mice. Furthermore, we explored the efficacy of direct intraneoplastic and systemic delivery of AphiG. Systemic administration of AphiG (60 mg/kg intraperitoneally, twice per day on 10 consecutive days) significantly suppressed tumor growth but was not able to induce any cures. In contrast, intratumoral AphiG injections (60 or 40 mg/kg/twice a day for 4 days) induced complete tumor regression. Two weeks after the end of treatment no tumor cells were microscopically detectable. Animals were free of tumor for more than 90 days. Histologic examination of inner organs and bone marrow did not reveal any apparent toxic effects of AphiG. These data strongly indicate that AphiG deserves further evaluation as a specific treatment for neuroblastoma.
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PMID:Aphidicolin glycinate inhibits human neuroblastoma cell growth in vivo. 1020 92

The aim of the study was to determine the major source and extent of metal pollution in a residential area of Greater Calcutta. In this area approximately 50,000 people reside in the vicinity of a lead factory that produces lead ingots and lead alloys. Many people, especially children, are affected by lead toxicity. Soils, waters, road dust, leaf dust, leaves and pond sediments were sampled in and around the factory area. Aliquots of the samples were mineralized with nitric acid and hydrogen peroxide in a microwave system. Lead and 19 other elements were quantified in the digests by inductively coupled plasma mass spectrometry. The performance of the procedure was confirmed by analyzing NBS-BCR standard reference soil, leaves, sediment samples. The soils are highly contaminated not only with lead (4.7%), but also with Cd (0.08%), Ag (0.001%), Cu (0.02%), Zn (1.0%), As (1.0%), Mo (0.003%), Sn (0.003%) and Hg (0.03%) (metal concentrations given in parentheses are maximum). Moving away from the smelter, most of metal concentrations, especially Pb, As, Mo, Cu, Hg, Zn, Cd, Sn and Ag, decreased exponentially over increasing distance. In the residential areas near the smelter, notably to the west side of the factory, metal concentrations significantly breached the threshold trigger values set in India by the Central Pollution Control Board (CPCB). Particulate materials from the smelter stack appear to contaminate soils up to at least 0.5 km. However, abnormally high metal levels in the immediate smelter area may be due to primarily fugitive emissions. The surface waters are only contaminated by arsenic ranges from 0.05 to 13.5 mg/l, but the ground water is currently not polluted by lead and arsenic. An appropriate treatment plant with some intervention measures should be taken to save the locality.
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PMID:Determination of lead and other metals in a residential area of greater Calcutta. 1023 82

Massic activity values obtained for NBS/NIST tritiated water SRMs 4927 and 4927E, using internal gas-proportional counting, are reported. The massic activity ratios of all of the available NBS/NIST tritiated water SRMs and samples of the Level 1 and Level 3 tritiated water standards produced by the National Physical Laboratory (NPL) in 1996 were measured using an extensive series of liquid-scintillation intercomparisons. New massic activity values obtained for the NPL standards, using the gas counting results for SRM 4927E and the results of the liquid-scintillation intercomparison, are also reported. A new determination of the half-life of tritium was made using massic activity data for SRM 4927 over a period of 38 years. The new value is (4504+/-9) (one standard deviation) days. This value differs significantly from the previous NBS/NIST value but is in good agreement with the value recommended in the Evaluated Nuclear Structure Data File (ENSDF).
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PMID:Calibration of the National Institute of Standards and Technology tritiated-water standards 1072 1

Equinatoxin-II (EqTx-II), a cytotoxic protein (mol.wt 20 kDa) isolated from the sea anemone Actinia equina, was found to consistently increase the three-dimensional projected area of differentiated neuroblastoma (NG108-15) cells provided Ca(2+) was present in the medium. No swelling was detected when external NaCl was replaced by sucrose, but replacement of NaCl by Na-isethionate did not prevent the swelling, as revealed by confocal laser scanning microscopy. In addition, microspectrofluorometric measurements in cells preloaded with the Ca(2+) indicator fura-2/AM revealed that EqTx-II (100 nM) markedly increased the fluorescence (F(340)/F(380)) ratio indicating a rise of intracellular Ca(2+) concentration ([Ca(2+)](i)). The elevation of [Ca(2+)](i) exhibited two components that seem to be related to the kinetics of EqTx-II-induced Ca(2+) entry since pretreatment of cells with Ca(2+)-ATPase inhibitors (thapsigargin), Ca(2+) channel blockers (nifedipine and Gd(3+)) or prolonged exposure to a high K(+) (75 mM) medium did not alter EqTx-II-induced Ca(2+) signals. As far as we know, this is the first demonstration that EqTx-II causes swelling of neuroblastoma cells and that this effect is correlated both with an increase of [Ca(2+)](i) and needs the presence of extracellular Na(+). It is suggested that EqTx-II has the ability to insert into the plasma membrane of neuroblastoma cells and to form pores altering the membrane permeability and the intracellular osmolality, inducing a marked influx of water into the cells.
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PMID:Ca(2+) and Na(+) contribute to the swelling of differentiated neuroblastoma cells induced by equinatoxin-II. 1077 55

This paper describes a methodological approach for the assessment of the amount of surrogate dry deposition of several toxic heavy metals (Cd, Cr, Cu, Ni, Pb, V, Zn) associated with atmospheric particulate matter at ground level. The objectives of the study were twofold: i) the evaluation of several techniques for the digestion of dry deposition samples for trace metal analysis; ii) the comparison of the results from two samplers with different collecting surfaces. A dry solid surface sampler (DRY sampler, Andersen--USA) and a water layer surface sampler (DAS sampler--MTX Italy) were employed. The samples were collected over a one-year period in an urban site of Bologna (northern Italy). A description is given of the complete procedure, from sampling to data elaboration, including sample storage, digestion and analytical methods. According to the results obtained with three different digestion techniques (Teflon bomb, microwave digester and Teflon flask with vapour cooling system), the highest recovery rate was achieved by the Teflon bomb procedure employing an NBS 1648 Standard Reference Material; 90-95% of the elements considered were recovered by dissolution in a pressurized Teflon bomb with an HNO3-HF mixture. Given these results, the technique was adopted for dry deposition sample digestion. On the basis of the amount of heavy metals measured as monthly deposition fluxes (microg/m2), the collecting efficiency of the DAS sampler for a number of elements was found to be as much as two to three times greater than that of the DRY sampler.
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PMID:Heavy metals in atmospheric surrogate dry deposition 1090 20


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