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2.
Ther Drug Monit ; 16(3): 323-6, 1994 Jun.
Article in English | MEDLINE | ID: mdl-8085286

ABSTRACT

We evaluated a rapid monoclonal antibody theophylline assay for two reasons: (a) to determine its specificity with respect to the possible confounding influence of a structurally related xanthine, enprofylline, and (b) to assess its accuracy relative to high-performance liquid chromatography (HPLC). Blood samples were taken from 233 patients who had been randomized in double-blind fashion to receive either oral theophylline (n = 117) or enprofylline (n = 116) for the treatment of chronic reversible obstructive airways disease. Monoclonal antibody assays (MAAs) were performed in 10 clinical sites by 10 trained paramedical technicians. Three patients, who actually received enprofylline but not theophylline, had MAA theophylline values of > or = 3.2 micrograms/ml, giving a specificity of 97%. HPLC determination of simultaneous blood samples confirmed that theophylline levels were in fact < 3.2 micrograms/ml and that theophylline was not being taken surreptitiously. Good correlation was observed between MAA and HPLC in patients taking theophylline (y = 1.07 x + 0.36; r = 0.93; standard error of the estimate (SEE) = 1.93). However, there was wide variability from technician to technician such that r values for individual sites ranged from 0.67 to 0.99. Based on the overall correlation, the prediction of an individual HPLC value from an individual MAA value had broad 95% confidence limits: when the MAA value was 10 micrograms/ml, the predicted HPLC value was 9.19 +/- 3.32; when MAA = 15 micrograms/ml; HPLC = 13.19 +/- 3.33; and when MAA = 20 micrograms/ml; HPLC = 17.19 +/- 3.36.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Antibodies, Monoclonal , Bronchodilator Agents/blood , Theophylline/blood , Xanthines/blood , Adult , Antibody Specificity , Bronchodilator Agents/immunology , Chromatography, High Pressure Liquid , Cross Reactions , Double-Blind Method , Humans , Immunoassay , Theophylline/immunology , Xanthines/immunology
3.
Zh Mikrobiol Epidemiol Immunobiol ; (12): 6-10, 1990 Dec.
Article in Russian | MEDLINE | ID: mdl-2099072

ABSTRACT

As revealed in experiments on V. cholerae, highly diluted cholera antiserum enhanced the inhibitory action of the enzymatic link xanthine oxidase-xanthine-Fe2+ on the multiplication of V. cholerae, while low dilutions of the antiserum weakened this action. Normal rabbit serum produced no such effect. The antivibrionic effectiveness of the immune molecular cycle, viz. antiserum--the xanthine oxidase enzymatic link, was found to depend also on the concentration of xanthine. Immune antibodies to cholera antigens activated the bacteriostatic action of the enzymatic link at the concentration of xanthine oxidase equal to 0.0125 g/l and its bactericidal action at the concentration of xanthine oxidase equal to 0.025 g/l. In this article the values of the specificity indices of immune interaction and immunological effectiveness, characterizing the effectiveness of immune molecular cycles (antibodies--the xanthine oxidase enzymatic link), are presented.


Subject(s)
Antibodies, Bacterial/immunology , Vibrio cholerae/immunology , Xanthine Oxidase/immunology , Xanthines/immunology , Animals , Antigen-Antibody Reactions/immunology , Dose-Response Relationship, Immunologic , Immune Sera/immunology , Immunization , In Vitro Techniques , Rabbits , Xanthine
4.
Farmakol Toksikol ; 49(3): 74-7, 1986.
Article in Russian | MEDLINE | ID: mdl-3013676

ABSTRACT

On mice immunized with ram erythrocytes it was shown that caffeine and theophylline (15 to 240 mg/kg thrice at different time intervals with respect to the antigenic stimulus) possess identical immunotropic activity. High doses of methylxanthines injected a few days before immunization increased and being administered during immunization decreased the indices of humoral immunity. Low doses of the drugs stimulated immunity but only when administered at the time close to the antigenic stimulus application.


Subject(s)
3',5'-Cyclic-AMP Phosphodiesterases/antagonists & inhibitors , Caffeine/immunology , Theophylline/immunology , Animals , Dose-Response Relationship, Drug , Erythrocytes/immunology , Female , Hemagglutinins/analysis , Hemolysin Proteins/analysis , Immunization , Mice , Spleen/drug effects , Spleen/immunology , Time Factors , Xanthines/immunology
5.
Ann Clin Biochem ; 22 ( Pt 5): 519-25, 1985 Sep.
Article in English | MEDLINE | ID: mdl-3904588

ABSTRACT

Described is the development of a fluoroimmunoassay for theophylline using a fluorescein labelled derivative of theophylline as tracer and antibodies coupled to magnetizable solid-phase particles. Three approaches are described for the preparation of antibodies for theophylline, of which one produced highly specific, high titre antibodies. The fluoroimmunoassay using these antibodies required a 10 microL sample, reached equilibrium within 5 min, and the results correlated closely with those of an established enzymoimmunoassay method. Potentially interfering endogenous fluorophores from the serum sample were reliably removed at the separation step of the bound and free fractions. There was no significant cross-reactivity with all other structurally related compounds.


Subject(s)
Fluorescent Antibody Technique , Theophylline/blood , Animals , Antibody Specificity , Caffeine/immunology , Cross Reactions , Female , Fluorescein , Fluoresceins , Humans , Rabbits , Sheep , Theobromine/immunology , Theophylline/immunology , Xanthines/immunology
6.
Vopr Med Khim ; 23(2): 232-7, 1977.
Article in Russian | MEDLINE | ID: mdl-70110

ABSTRACT

Conjugated antigens of xanthine- and theophylline-protein were synthesized by the reaction of diazosalts of 8-aminoxanthine and 8-aminotheophylline with bovine serum albumin. UV-spectra of the synthesized preparations were studied and content of xanthine and theophylline, covalently bound with the substances, was estimated. Immunization of animals with the conjugates was found to cause the occurrence of antibodies in blood serum, which bound specifically various derivatives of purine.


Subject(s)
Antigens , Serum Albumin, Bovine/immunology , Theophylline/immunology , Xanthines/immunology , Animals , Antibody Specificity , Chemical Phenomena , Chemistry , Chromatography, Gel , Epitopes , Protein Binding , Rabbits , Spectrophotometry, Ultraviolet
7.
J Pharmacol Exp Ther ; 199(3): 679-86, 1976 Dec.
Article in English | MEDLINE | ID: mdl-1033273

ABSTRACT

Caffeine was analyzed in human plasma and saliva by a simple, rapid, and sensitive radioimmunoassay procedure. Immunization of rabbits with an antigen prepared by coupling 7-(5-carboxypentyl)-1,3-dimethylxanthine to bovine serum albumin resulted in the formation of antibodies selective for caffeine as opposed to various mono- and dimethylxanthines, mono-, di-, and trimethyluric acids and a variety of common drugs. The radioligand used for competitive binding studies was 7-(2,3-3H2-propyl)-1,3-dimethylxanthine. The procedure permits direct analysis of caffeine in plasma or saliva without extraction. Comparison with a high pressure liquid chromatography method for the analysis of caffeine gave satisfactory results and showed no evidence for interference by metabolites. A caffeine half-life of 4.0 hours determined by the radioimmunoassay was in agreement with previous work. Comparison of human plasma and saliva levels by the radioimmunoassay procedure indicated approximately equal concentrations in the two fluids.


Subject(s)
Caffeine/analysis , Saliva/analysis , Adult , Animals , Antibody Formation , Caffeine/blood , Chromatography, High Pressure Liquid , Humans , Methods , Rabbits/immunology , Radioimmunoassay , Serum Albumin, Bovine , Xanthines/immunology
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