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)

Determination of urinary homovanillic acid (HVA) is an important analysis to establish the diagnosis and prognosis of neuroblastoma. A method is presented for the determination of this metabolite of dopamine using its reaction with 1-nitroso-2-naphthol and nitrous acid. The method has shown a sensitivity, specificity, positive predictive value, negative predictive value, and efficiency of 100%, 97.4%, 92.3%, 100%, and 98%, respectively. In the last two years, four new cases of neuroblastoma have been diagnosed, with the use of this method, one of which has no increase in the concentration of urinary vanillylmandelic acid.
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PMID:Determination of urinary homovanillic acid using the nitrosonaphthol reaction. 357 40

1-Nitroso-2-naphthol reacts with various 5-hydroxyindoles as well as para-substituted phenols and guaiacols. Consequently, this reaction has long been used to measure tyrosine in tyrosinosis and tyrosinemia, homovanillic acid in neuroblastoma, and 5-hydroxy-3-indoleacetic acid in the carcinoid tumor. We report here on the specificity of this reaction, as well as our early observations with respect to the chemical basis of the reaction.
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PMID:The chemical basis and specificity of the nitrosonaphthol reaction. 619 18

The suitability of 1-nitroso-2-naphthol (NN) as a complexing agent for on-line preconcentration of cobalt using C(18) microcolumn with FI-FAAS system has been tested. Various parameters affecting the complex formation and its elution were optimized. Reagent solution (2.5x10(-3) mol l(-1)) and aqueous sample solution acidified with 0.1% (v/v) nitric acid were on-line mixed in a reaction coil set at 65+/-1 degrees C and flowed through the microcolumn for 30 s. The pH of the mixed solution was adjusted to 3 approximately 4 by adding HNO(3) (1 mol l(-1)) or NaOH (1 mol l(-1)) in the reagent solution. The adsorbed complexes in the microcolumn were eluted with ethanol (acidified to 1% nitric acid) in 10 s into the nebulizer of FAAS. A good precision (1.6% for 100 mug l(-1) Co(II), n=10), high enrichment factor 17.2, with detection limit (3sigma) 3.2 mug l(-1), and sample throughput (90 h(-1)) were obtained. The method was applied on the certified reference materials (CRMs) i.e. NBS-362 and NBS-364 (special low alloy steel), for the determination of cobalt and the results were in good agreement with the certified values.
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PMID:Cobalt determination with FI-FAAS after on-line sorbent preconcentration using 1-nitroso-2-naphthol. 1896 99