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)

The free energies of immersion for three hydroxyapatite samples of different origin and method of preparation were determined from water adsorption isotherms at 20 and 25 C. The free energies varied with the temperature of the isotherm, changing linearly with the outgassing temperature in the range of 20 and 300 C. The samples outgassed at 300 C yielded free energy of immersion values of 365, 432, and 476 ergs/cm2 for the VIC-, NBS-, and TVA-HAP, respectively. Work of adhesion and work of spreading were calculated for water on these samples.
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PMID:Free surface energy change for water adsorbed on hydroxyapatite. 26 53

Investigation of dopamine-beta-hydroxylase (DBH) serum activity as a potential diagnostic/prognostic tool for neuroblastoma did not confirm previous reports. However, age-dependent differences in normal children's DBH "activation" by water dilution +/- copper addition was revealed. These findings of age-related DBH effector differences suggest that the strong age relationship of DBH activity may be due to alterations in effectors. Additionally, these effectors may be variably affected by assay methodology, influencing DBH results obtained in neuroblastoma and other disease states.
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PMID:Dopamine-beta-hydroxylase effectors in neuroblastoma. 48 96

In the application of hyperthermia to cancer management, it would be useful to know the temperature/tim profile of heated tissues, including the tumor and surrounding normal structures. To obtain this information, knowledge of thermal conductivity and diffusivity of the tissues is required. The thermal conductivity of neuroblastoma was determined by a transient technique to be 89% of the thermal conductivity of water at 25 degrees, 37 degrees, and 44 degrees C. From the latter measurements, the thermal diffusivity of neuroblastoma cells was estimated as 93% of the thermal diffusivity for water. Further, in this study of neuroblastoma cells, the water content was measured as 87.4 g/100 ml of cells, a rather high value not atypical of tumor cells. From literature values of density, specific heat, and thermal conductivity, values for the thermal diffusivity of a variety of normal tissues were estimated. The thermal diffusivity values of normal tissues and neuroblastoma cells exhibit an excellent correlation with water content.
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PMID:Thermal conductivity and diffusivity of neuroblastoma tumor. 71 75

The neurotoxic effects of the commercial organic solvents n-hexane and methyl n-butyl ketone (MBK), recently discovered to cause profound peripheral neuropathy in man, were studied in neuronal-like cells in tissue culture. These agents are known to induce marked proliferation of 10nm neurofilaments in peripheral and central axons of both humans and rats. In a murine neuroblastoma cell line, previously reported to show filamentous hyperplasia when exposed to aluminum ions, both MBK and n-hexane induced a highly reproducible series of cytotoxic effects at the light and electron microscopic levels and caused dose-dependent inhibition of cellular proliferation. In contrast, two closely related but clinically non-toxic solvents, methyl isobutyl ketone and methyl ethyl ketone, caused little or no cytopathological or growth inhibiting effects. MBK and its major water soluble derivative, 2,5-hexane dione (HD), produced identical cytotoxic changes in vitro, supporting the postulate that HD is the toxically active agent in victims exposed to MBK. Although MBKlthought MBK and n-hexand adversely affected the extension of maintenance of neuritic processes, electron microscopy and immunofluorescent reaction failed to reveal any proliferation of 10 nm cytoplasmic filaments in the intoxicated cells. Also, these agents had no deleterious effect on in vitro brain microtubule polymerization. In contrast, aluminum ions produced a doserelated inhibition of neurotubule assembly, similar to that seen with the filament-inducing agents colchicine and vinblastine. The results suggest that the fibrous cytoskeleton may not be the primary or essential target of MBK n-hexane and related human neurotoxins.
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PMID:Effects of neurotoxic industrial solvents on cultured neuroblastoma cells: methyl n-butyl ketone, n-hexane and derivatives. 73 76

Biomethylation of metals, including arsenic, apparently occurs as a global process. Health control strategies therefore depend on accurate analysis of arsenic's environmental mobility. Determining to what extent biotransformations occur and how resultant organometal(loids) are sequestered in food chains requires sophistication beyond present-day total element determinations. Rather, active molecular forms of arsenic must be speciated for each environmental compartment, and it is necessary to quantify the dynamics of arsenic's mobility. Thus, new chemical facts are needed yielding rates of methylation or demethylation of arsenic; partition coefficients of organoarsenicals between air, water, and organic phases; and arsenic redox chemistry in polar media. NBS research in this context is reviewed with examples of recent results emphasizing speciation methodology. Topic areas discussed are: the nature of aquated methylarsenic species (NMR and laser-Raman spectroscopy); transport of methylarsenicals from aqueous media (gas chromatography-graphic furnace AA detection applied to metabolic Me3As formation); and speciation of involatile organoarsenicals in aqueous media (demonstration of HPLC utilizing element-specific AA detection and appraisal of electrochemical detectors).
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PMID:Questions concerning environmental mobility of arsenic: needs for a chemical data base and means for speciation of trace organoarsenicals. 90 86

The water-soluble carbodiimide salt 1-ethyl-3-(3'-dimethylaminopropyl)carbodiimide. HCl (EDCI-HCl) has been shown to increase the complement-dependent lysis of cultured mouse neuroblastoma C1300 cells by two types of antibody: (1) natural antibodies in the sera of normal (nonimmunized) rabbits, and (b) serum antibodies from snygeneic tumor-bearing A/HeJ mice. In the latter case, both the level of serum antibodies and the extent of carbodiimide enhancement of immune lysis were demonstrated in vitro to be substantially greater with sera from mice bearing 21-day-old tumors relative to 4-day-old tumors. The carbodiimide EDCI-HCl has also been found to increase the complement-dependent lysis of cultured TA3 carcinoma cells by serum antibodies from isogeneic LAF1/J mice bearing ascites tumors in advanced stages of growth. Finally, it has been shown that EDCI-HCl exerts an antitumor activity in vivo that is significantly greater against 21-day-old than against 4-day-old neuroblastoma c1300 tumors. The increase in EDCI-HCl activity with tumor age is contrary to the response that would be expected if this drug were serving as an antimetabolite. This is evidenced by data showing that the antimetabolite 6-thioguanine is most effective against young rapidly growing neuroblastoma C1300 tumors. The correlation between carbodiimide antitumor activity and host production of cytotoxic antibodies suggests that EDCI-HCl may operate in vivo by an immunological mechanism comparalbe to that demonstrated in vitro.
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PMID:Carbodiimide enhancement of complement-dependent antibody-mediated tumor cell lysis in vitro and antitumor activity in vivo. 111 28

The inhibitory effect of lipophilic acids, antimicrobial food additives, and analgesics-antipyretics was examined at concentrations from 0.1 to 100 mM in bacteria (Bacillus subtilis and Escherichia coli) and mammalian cells (HeLa, human fibroblasts, and mouse neuroblastoma cells). Most compounds inhibit the growth of HeLa cells about as efficiently as that of B. subtilis. However, butyrate and propionate, as well as acetaminophen, antipyrene, phenacetin, and salicylamide, inhibit HeLa at millimolar concentrations whereas, at least 10 times higher concentrations are needed to inhibit B. subtilis. The concentrations needed to inhibit growth by 50% decrease with increasing octanol-water partition coefficients of the compound. Growth of E. coli is inhibited similar to that of B. subtilis by all compounds except butylbenzoate, decanoate, and linoleate which cannot penetrate the lipopolysaccharide layer. All growth inhibitors inhibit amino acid uptake into bacteria and their vesicles, and oxygen consumption in bacteria. In HeLa cells or human fibroblasts, neither amino acid uptake nor adenine 5'-triphosphate synthesis are inhibited by fatty acids at concentrations that completely inhibit growth. Short chain fatty acids (propionate, butyrate, and pentanoate) induce in HeLa the formation of cell processes. In neuroblastoma cells, grown in the presence of 10% fetal calf serum, butyrate also induces such processes which slowly continue to grow in length for at least 7 days; these processes differ in speed of formation, width, and cycloheximide susceptibility from the thin processes produced by serum deprivation alone.
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PMID:Inhibitory effects of lipophilic acids and related compounds on bacteria and mammalian cells. 113 88

The effects of chlorhexidine digluconate preadded to urine samples for a neuroblastoma-screening test in preventing the break-down of creatinine (Cre), vanillylmandelic acid (VMA), and homovanillic acid (HVA) by creatinine-cleaving bacteria and the influence of the added disinfectant on the HPLC determination of urinary Cre, VMA, vanillillactic acid (VLA) and HVA. Laboratory or field experiments showed that preadded disinfectant (0.02% volume) nearly completely inhibited the growth of the bacteria and satisfactorily protected urinary Cre, VMA, and HVA from bacterial decomposition. Chlorhexidine digluconate was comparable to benzalkonium chloride in its inhibitory effects on the growth and activities of creatinine-cleaving bacteria. Unlike benzalkonium chloride, chlorhexidine digluconate added to urine samples gave no troubles in subsequent analytical processes. Addition of the disinfectant (0.02% volume) to standard Cre, VMA, VLA, and HVA solution did not affect retention times and sensitivities in HPLC analyses. To estimate influences of the added disinfectant on the serial HPLC determinations of VMA, VLA, and HVA on a large number of urine samples (40, 80, 120, 160, 200, or 5, 500), HPLC analyses were performed on standard VMA, VLA, and HVA solution with repeated injection of the disinfectant in great amounts into a column. The results showed no appreciable changes in the retention times and sensitivities of VMA, VLA, and HVA, and almost complete elution of the disinfectant retained on the column were possible with water-methanol (1:1, 2:8) or methanol washing.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Bacterial contamination of infant urine samples obtained from filter papers used in neuroblastoma-screening tests. (6) Protective effects of preaddition of chlorhexidine digluconate in filter papers or containers for urine on bacterial break-down of creatinine, vanillylmandelic acid and homovanillic acid]. 146 45

The ultimate purpose of the present study was to evaluate correlations between acute in vivo and in vitro toxicity and log P (P is n-octanol-water partition coefficient). The in vitro toxicity to cloned cells (neuroblastoma N18TG-2 and glioma C6) in culture (ED50) and the in vivo toxicity to mice (LD50) of ethylene glycol ethers were studied in terms of the structure-activity relationship. The test ethers showed a wide range of ED50 values in both cells. LD50 was determined under two conditions: LD50-cont. was estimated in mice pretreated with olive oil and LD50-CCl4 in CCl4-pretreated mice. Multiple regression analyses revealed a significant correlation between log 1/LD50 and log P as follows: log (1/LD50-cont.) = -0.120 (log P)2+0.487log P-1.182, and log (1/LD50-CCl4) = -0.128 (log P)2+0.566log P-1.157. There was no significant correlation either between ED50 and LD50 or between ED50 for N18TG-2 and ED50 for C6. The results suggest that metabolic activation might not occur during acute toxicity from the ethers, and that hydrophobicity, expressed as log P, plays an important role in acute toxicity.
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PMID:Structure-toxicity relationship of ethylene glycol ethers. 161 Mar

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


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