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Aim To study features of diagnosis and treatment of acute myocardial infarction (AMI) in Russian hospitals, results of the treatment, and early and late outcomes (6 and 12 months after AMI diagnosis); to evaluate the consistence of the treatment with clinical guidelines; and to evaluate patients' compliance with the treatment.Material and methods The program was designed for 3 years, including 24 months for recruitment of patients to the study. The study will include 10,â000 patients hospitalized with a confirmed diagnosis (I21 according to ICD-10) of ST segment elevation acute myocardial infarction (MI) (STEMI) or non-ST segment elevation MI (NSTEMI) based on criteria of the European Society of Cardiology Guidelines on Forth Universal Definition of Myocardial Infarction (2018). The follow-up period was divided into three stages: observation during the stay in the hospital and at 6 and 12 months following inclusion into the registry. The primary endpoint included cardiac death, nonfatal MI during the hospitalization and after one-year follow-up. Secondary endpoints were 6-months and one-year incidence of repeated MI, heart failure, ischemic stroke, clinically significant hemorrhage, unscheduled revascularization after discharge from the hospital, and the proportion of patients who continue on statins, antiplatelet drugs, and drugs of other groups for 6 months and 1 year.Results The inclusion of patients into the registry started in 2020 and will continue for 24 months. By the time of the article publication (June, 2021), more than 2,000 patients will be included.Conclusion REGION-MI (Russian rEGIstry Of acute myocardial iNfarction) is a multicenter, retrospective and prospective observational cohort study that excludes any interference with the clinical practice. Results of the registry will help to analyze a real picture of medical care provided to patients with myocardial infarction and to schedule ways to improve the situation.
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Infarto do Miocárdio , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/terapia , Estudos Prospectivos , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Federação Russa/epidemiologia , Fatores de Tempo , Resultado do TratamentoRESUMO
Currently, there is a constant expansion of the range of narcotic substances that differ from each other by a small structural fragment. The option of determining narcotic substances using test panels is widespread due to its rapidity and high specificity through the use of immunochemical reactions. The purpose of the study was to optimize the determination of morphine and amphetamine in bioobjects (synthetic and natural urine) using immunochromatographic analysis with new test panels and to select the optimal conditions for mass analysis. Test panels were used to detect the presence of amphetamine and morphine. For color recording of the results of analysis, colloidal gold nanoparticles were used. The principle of operation of these test panels is described. The sensitivity of the test panels is such that it is possible to avoid false-positive results. It was found that with the help of test panels it is possible to determine narcotic substances in a concentration lower than stated in the instructions (300 ng/ml). The actual detection limit for amphetamine was 75 ng/ml and morphine 100 ng/ml. The analytical characteristics of the developed metho-dology were determined: detection limit, precision, truth and specificity. The specificity was proved by conducting ICA to detect the presence of cross-reactions of test systems to amphetamine and morphine using structural analogues - adrenaline 1000 and codeine 300, respectively. The study did not receive false positive results for these molecules using the proposed test panels. Immunochromatographic test systems are optimal for drug detection, especially when conducting mass studies.
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Nanopartículas Metálicas , Entorpecentes , Anfetamina , Ouro , MorfinaRESUMO
The antioxidant activity and protective effect in the toxicity model of H2O2 were studied for arachidonic (AA-CHOL), docosahexaenoic (DHA-CHOL), linoleic (Ln-CHOL), and oleic (Ol-CHOL) fatty acids, as well as arachidonoyl dicholine (AA-diCHOL) and O-arachidonoyl bistetramethylaminoisopropanol (ABTAP). AA-CHOL, DHA-CHOL and Ln-CHOL provided a 20% increase in cell survival. AA-CHOL, AA-diCHOL, Ol-CHOL, and ABTAP had a radical-scavenging effect in the ABTS test, approximately equal to the activity of a standard radical scavenger Trolox.
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Antioxidantes/química , Ácidos Araquidônicos/química , Colina/química , 2-Propanol/química , Ácido Araquidônico/química , Linhagem Celular Tumoral , Cromanos/química , Ácidos Docosa-Hexaenoicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Ácidos Graxos , Radicais Livres/química , Humanos , Peróxido de Hidrogênio/química , Ácido Linoleico/química , Ácido Oleico/químicaRESUMO
Presented the results of the clinical study of 30 patients with moderate rhinosinusitis (13 (43.3%) men, 17 (56.7%) women, age from 18 to 68 years). Among those patients, the inflammation of one paranasal sinus was observed in 7 (23.3%) cases, polysinusitis was observed in 23 (76. 7%) cases. All patients were randomized into 2 groups of 15 people. In both groups, patients received systemic antibiotic therapy, nasal irrigation therapy, and NSAIDs. In the control group, topical decongestants were used; in the experimental group the antimicrobial drug Polydexa with phenylephrine was used as a local therapy. The purpose of the study was to evaluate the clinical efficacy of Polydexa with phenylephrine in the complex treatment of moderate acute rhinosinusitis. The evaluation criteria were statistically significant comparison of clinical and laboratory parameters of both groups. Confirmed the anti-inflammatory, antimicrobial effects of the drug, made conclusions about the significant clinical efficacy, tolerability, positive effect on mucociliary clearance and safety of nasal spray Polydexa with phenylephrine.
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Anti-Infecciosos , Rinite , Sinusite , Adulto , Idoso , Antibacterianos , Anti-Infecciosos/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Seios Paranasais , Rinite/tratamento farmacológico , Sinusite/tratamento farmacológico , Adulto JovemRESUMO
Three kinds of immunoassays for the determination of gentamicin in milk samples were developed and validated. First, a fast and easily-performed fluorescence polarization immunoassay was used for characterization of the employed polyclonal antibody. The calculated Kaff were (1.9±0.4)×10(9)Ð(-1) and (6.0±0.2)×10(6)Ð(-1) for the high- and low-affinity fractions respectively. The assay was characterized with a good sensitivity, the limit of detection being 5µgkg(-1). Two different kinds of detection labels, i.e. colloidal gold (CG) and quantum dots (QDs), were evaluated for use in lateral-flow format with respect to rapid visual on-site testing. The cut-off levels for both qualitative formats were selected based on the maximum level for gentamicin in milk established by the European Commission, 100µgkg(-1), resulting in a 10µgkg(-1) cut-off considering sample dilution. The intra-laboratory validation was performed with sterilized milk samples artificially spiked with gentamicin at concentrations less than, equal to, and greater than the cut-off level. It was shown that milk products could be analyzed without any sample preparation, except for dilution with the buffer solution. The rates of false-positive and false-negative results were below 5% for both labels. The different developed immunoassays were tested towards gentamicin determination in artificially-spiked and naturally contaminated milk samples.
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Antibacterianos/análise , Gentamicinas/análise , Leite/química , Animais , Antibacterianos/química , Antibacterianos/imunologia , Anticorpos/imunologia , Imunoensaio de Fluorescência por Polarização , Contaminação de Alimentos/análise , Gentamicinas/química , Gentamicinas/imunologia , Ouro/química , Nanopartículas Metálicas/química , Ovalbumina/química , Pontos Quânticos/químicaRESUMO
Characteristics of the fluorescence polarization immunoassay (FPIA) as a mean for express control of antibiotic levels in various specimens and its advantages vs. other analytical tests are described. The developmental stages of the analytical procedure and its parameters are considered for chlorampnenicol as an example. The analysis is based on competitive interaction of anti-chloramphenicol antibodies with the chloramphenicol-fluorophore conjugate and the potential free chloramphenicol in the specimen. The experimental results of the comparison of the chloramphenicol FPIA with the use of two conjugates differing in the length of the bridge length between the antibiotic functional groups and fluorophore (fluorescein) are presented. The requirements to the choice of the antibody and conjugate concentrations providing highly sensitive detection are characterized. The detection limit of chloramphenicol in the FPIA was 10 ng/ml and the determination of the concentrations ranged from 20 ng/mI to 10 mcg/ml. The time of the assay was 10 min.
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A technique was developed for fluorescence polarization immunoassay (FPIA) of ractopamine, a toxic low molecular weight nonsteroidal growth regulator belonging to the most controlled contaminants of food products of animal origin. The assay is based on the competition between a sample containing ractopamine and ractopaminefluorophore conjugate for binding to antibodies. The competition is monitored via changes in the degree of fluorescence polarization for plane-polarized excitation light, which differs for the free and antibody-bound forms of the conjugate. The optimal assay conditions were established, ensuring a high accuracy and minimal detection limit. The developed assay demonstrated a detection limit of 1 ng/mL and a range of detectable concentrations of 2.350 ng/mL, which met the requirements of sanitary control. The duration of the analysis was 10 min. The possible application of the developed FPIA was demonstrated with testing of turkey meat. The speed and simplicity of the proposed assay define its efficiency as a screening tool for safety of foods.
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Análise de Alimentos/métodos , Fenetilaminas/análise , Animais , Imunoensaio de Fluorescência por Polarização/métodos , HumanosRESUMO
A rapid immunochromatographic assay was developed for the control of tetracycline (TC). The assay is based on the competition between immobilized TC-protein conjugate and TC in a tested sample for binding with polyclonal anti-TC antibodies conjugated to colloidal gold during the flow of the sample along a membrane strip with immobilized reactants. Conjugation of colloidal gold and the total immunoglobulin (IgG) fraction of polyclonal antibodies was used to increase the assay sensitivity to ensure low content of specific antibodies in the conjugate. This allowed effective inhibition of free TC and conjugate binding in the strip test zone. Photometric marker registration allows control of the reduction of binding, thereby enhancing detection sensitivity. The proposed assay allows TC to be detected at concentrations up to 20 ng/mL, exceeding the limit of detection of the known analogues, in a wide working range (more than two orders) of 60 pg/mL to 10 ng/mL, ensured through the use of polyclonal antibodies. The assay time is 10 min. The efficiency of the designed assay is shown to identify TC in milk; the degree of recovery of TC ranges from 90 to 112%. The precision of the concentrations measurements was no more than 10%.
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This manuscript describes the development of a sensitive, fast and easily-performed fluorescence polarization immunoassay (FPIA) for the mycotoxin aflatoxin B1 (AFB1) in various beer samples, both lager and dark. The highest sensitivity was determined for six poly- and monoclonal antibodies selective towards aflatoxins. The sample pretreatment design was emphasized since beer samples are characterized by extremely diverse matrices. Herein, the choice of sorbent for effective removal of matrix interferences prior to analysis was crucial. The samples were diluted with a borate buffer solution containing 1% PEG 6000 and passed through the clean-up column packed with NH2-derivated silica. This sample pretreatment technique was perfectly suitable for the FPIA of lager beer samples, but for dark beer and ale it did not suffice. An artificial matrix was constructed to plot a calibration curve and quantify the results of the latter samples. The developed immunoassay was characterized by a limit of detection of 1 ng mL(-1). Apparent recovery values of 89-114% for lager and 80-125% for dark beer were established. The FPIA data for AFB1 was characterized by elevated linear regression coefficients, 0.9953 for spiked lager and 0.9895 for dark beer samples respectively.
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Aflatoxina B1/análise , Cerveja/análise , Contaminação de Alimentos/análise , Aflatoxina B1/química , Aflatoxina B1/imunologia , Anticorpos/imunologia , Boratos/química , Soluções Tampão , Imunoensaio de Fluorescência por Polarização , Polietilenoglicóis/química , Dióxido de Silício/químicaRESUMO
Twenty-seven patients with pain due to the imbalance of the body were examined. Clinical evaluation of patients before and after treatment included a general orthopedic examination, computer optical topography, surface electroneuromyography. The main group (17 patients) received injections of the drug lantoks in spastic muscles, the control group received a standard set of treatment to relieve spasticity (massage, exercise therapy, FTL, pharmacotherapy). The treatment gave a significant difference between the main and control groups in the results of changing the parameters of posture and electrophysiological parameters of muscle as well as the duration of pain relief. The results of the study confirm a significant impact of the local muscle relaxation on the parameters of posture. The high efficacy of "Lantoks" in the reconstruction of functional parameters in the groups of spastic muscles was shown.
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Toxinas Botulínicas Tipo A/uso terapêutico , Dor Musculoesquelética/tratamento farmacológico , Fármacos Neuromusculares/uso terapêutico , Equilíbrio Postural , Adolescente , Adulto , Idoso , Criança , Eletromiografia , Terapia por Exercício , Humanos , Massagem , Pessoa de Meia-Idade , Dor Musculoesquelética/fisiopatologia , Dor Musculoesquelética/terapiaRESUMO
This study has demonstrated the possibility of using immunochromatographic test strips for the reliable qualitative detection of amphetamine and methamphetamine in the urine samples at a cut-off level of 300 ng/ml. The test strips obtained from different manufactures are shown to be slightly different in terms of specificity as appears from the frequency of cross-reactions with various pharmaceutical products and narcotic drugs. Also, the use of the immunochromatographic strips makes it possible to determine amphetamine in a range of concentrations from 100 to 1000 ng/ml by measuring the intensity of test-line colour with the help of a TotalLab TL120 programmer and special scanning programs. The analysis for amphetamine using the NrcoStop (Osiris S) immunochromatographic strips failed to confirm the presence of this substance in the urine samples from the subjects who had drunk 0.5 l of energy drinks, such as Adrenaline RUSH, Red Bull, and Burn. It means that the presence of amphetamine in the urine should not be attributed to the consumption of such drinks.
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Anfetamina/urina , Cromatografia de Afinidade/métodos , Metanfetamina/urina , Fitas Reagentes , Detecção do Abuso de Substâncias/métodos , Cromatografia de Afinidade/instrumentação , Reações Cruzadas/imunologia , Humanos , Limite de Detecção , Reprodutibilidade dos Testes , Detecção do Abuso de Substâncias/instrumentaçãoRESUMO
A rapid pretreatment-free immunochromatographic assay was developed for the control of the streptomycin (STR) content in milk and dairy products. The assay is based on the competition between an immobilized STR-protein conjugate and STR in a sample to be tested for the binding to monoclonal anti-STR antibodies conjugated to colloidal gold during the flow of the sample along a membrane strip with immobilized reactants. It is possible to improve the cut-off level of positive and negative samples distinguished by a change in the molar STR to protein ratio in the immobilized conjugate. The cut-off level (500 ng mL(-1)) thus achieved corresponds to the stated MRL of STR in milk and dairy products. For STR concentrations in the range of 16-250 ng mL(-1) its content can be quantitatively measured based on the degree of binding of a colloidal gold label in the test strip zone with the immobilized STR-protein conjugate. The duration of the assay is 10 min. The selected sizes of membrane pores and colloidal gold particles allow the assay to be carried out at room temperature without additional reactants and pretreatment. The applicability of the assay for milk, whole milk, sour clotted milk, and kefir with different fat content (from 0.5% to 6%) was confirmed. The results of quantitative immunochromatographic assay show good correlation with traditional ELISA (r was equal to 0.935 and 0.940 for the series tested).
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Laticínios/análise , Imunoensaio/métodos , Leite/química , Estreptomicina/análise , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Bovinos , Ouro/química , Camundongos , Estreptomicina/imunologiaRESUMO
An enzyme immunoassay technique for the detection of sulfamethoxypyridazine in honey, developed using rabbit polyclonal antibodies raised against N-sulfonyl-4-aminobutyric acid, which contains a structural group characteristic of sulfonamides, is proposed. Under the optimized conditions, the sulfamethoxypyridazine detection limit was 0.05 ng/ml, with the entire analysis procedure taking 2 h. In total, 24 honey samples were tested using the protocol based on tenfold dilutions of samples without their preliminary treatment.
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Mel/análise , Técnicas Imunoenzimáticas , Sulfametoxipiridazina/análise , Animais , Anticorpos , Coelhos , Sensibilidade e EspecificidadeRESUMO
A pretreatment-free immunochromatographic assay for detection of chloramphenicol (CAP) in milk was developed. The assay is based on competition between CAP molecules in the sample and immobilized CAP-protein conjugate for binding to monoclonal anti-CAP antibodies conjugated with colloidal gold particles (average diameter 30nm). The assay is carried out in the course of sample flowing along test strip with immobilized reactants, and its results can be detected by the naked eye or by a photometric device. Effect of the concentration of immunoreactants on assay characteristics was studied. The assay protocol with maximal sensitivity and reliability was optimized using measured values of brightness of lines. Detection limit for CAP is 10ngmL(-1). Assay duration is 10min, and it can be carried out at room temperature without any additional devices and reactants. The developed test strip has been applied to CAP detection in dairy products.
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Cloranfenicol/análise , Cromatografia/métodos , Imunoensaio/métodos , Leite/química , Animais , Técnicas de Química Analítica , Colódio/química , Coloides/química , Relação Dose-Resposta a Droga , Análise de Alimentos , Ouro/química , Haptenos/química , Óptica e Fotônica , Reprodutibilidade dos Testes , Fatores de TempoRESUMO
A monoclonal antibody against zearalenone (ZEA) was produced and used successfully to develop a direct competitive enzyme-linked immunosorbent assay (DC-ELISA) for the analysis of ZEA in cereals. This DC-ELISA had a limit of detection of 0.15 +/- 0.02 microg l(-1) and an IC50 value of 1.13 +/- 0.16 microg l(-1). Matrix interference was minimized by dilution of the sample extract before ELISA assays. Aqueous methanol (80%) gave good extraction efficiencies, and the recovery from spiked rice, barley, and corn samples averaged between 87 and 112%. Although ZEA was detected in seven (9%) of 80 rice samples and in eight (16%) of 50 barley samples, the concentration of ZEA in samples was around or below the limit of detection of DC-ELISA. Among 38 corn samples, ZEA was detected in nine (24%) samples in the range 41.0-909.8 microg kg(-1). Re-analysis of the ELISA-positive corn samples by high-performance liquid chromatography (HPLC) confirmed that seven (18%) corn samples were positive. The ZEA results for corn showed very good agreement between DC-ELISA and a commercial AgraQant zearalenone kit (r2 = 0.98). Thus, the monoclonal antibody-based DC-ELISA could be applied to the preliminary screening of ZEA contamination when analysis of a large sample number is needed.
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Grão Comestível/química , Estrogênios não Esteroides/análise , Contaminação de Alimentos/análise , Zearalenona/análise , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Monoclonais/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/normas , Estrogênios não Esteroides/imunologia , Hordeum/química , Humanos , Oryza/química , Reprodutibilidade dos Testes , Zea mays/química , Zearalenona/imunologiaRESUMO
A rapid easy-to-use immunoassay was optimised for the non-instrumental detection of ochratoxin A (OTA) in beer. The analytical method involves preconcentration on the immunoaffinity layer inside a column followed by direct competitive ELISA detection in the same layer. The visual cut-off value, i.e. the lowest OTA concentration resulting in no colour development, was 0.2 microg L(-1). Assay validation was performed using samples spiked with OTA. Thirty-seven naturally contaminated samples were screened with the gel-based method developed and no false-negative results were obtained. The method described offers a simple, rapid and cost-effective screening tool, thus contributing to better health protection of consumers.
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Cerveja/análise , Imunoensaio/métodos , Ocratoxinas/análise , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos , Géis/química , Fatores de TempoRESUMO
The conjugative recombinant plasmid pIEM3 (KmR TcR) was constructed in order to introduce the cloned ctxB gene encoding the cholera toxin B subunit into the Vibrio cholerae cells. The plasmid was obtained as a result of co-integration of two plasmids: a conjugative plasmid, pIEM1(KmR), carrying mini-kan transposon and IS1 element, as well as the pCTdelta27(TcR) plasmid that is a derivative of the pBR322 which carries the cloned ctxB gene. The avirulent Vibrio cholerae strain eltor biovar deprived (according to the PCR analysis) of the key structural and regulatory pathogenicity genes and carrying a mutation in a single gene of the O1 antigen was chosen as the pIEM3 plasmid carrier strain. The cointegrate uncoupling was shown to take place in 5% the cholera vibrio cells followed by retention of only the multi-copy pCTdelta7 plasmid. This event leads to the formation of the TcRKmS clones characterized by high levels of the cholera toxin secreted B subunit production (10 to 14 microg/ml), one of these (KM93) being selected as a strain-producer of the protein. Molecular-genetic and biochemical assays were used to elucidate peculiar features of inheritance and expression of the cloned ctxAB gene within the KM93 cells. The expression of the cloned ctxB gene was shown to be independent of the presence of the toxR, tcpP, tcpH, toxT regulatory genes suggesting the existence of some other mechanisms that might exert their control over the transcriptional activity of the cholera toxin B subunit gene. Effective production of the cholera toxin B subunit would be also observed if the constructed producer strain was cultured under the conditions of industrial process. This indicates a possibility of its employment as a source of this protein involved in manufacturing cholera immunodiagnostic and prophylactic preparations.
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Toxina da Cólera/biossíntese , Vacinas contra Cólera/biossíntese , Microbiologia Industrial/métodos , Proteínas Recombinantes/biossíntese , Vibrio cholerae/genética , Toxina da Cólera/genética , Vacinas contra Cólera/genética , Conjugação Genética , Regulação Bacteriana da Expressão Gênica , Plasmídeos/genética , Proteínas Recombinantes/genética , Vibrio cholerae/crescimento & desenvolvimento , Vibrio cholerae/patogenicidade , Virulência/genéticaRESUMO
This review focuses on recent developments in immunochemical methods for detection of mycotoxins, with a particular emphasis on simultaneous multiple analyte determination. This includes high-throughput instrumental analysis for the laboratory environment (microtitre plate enzyme-linked immunoabsorbant assay (ELISA), different kinds of immunosensors, fluorescence polarization immunoassay, and capillary electrophoretic immunoassay), as well as rapid visual tests for on-site testing (lateral-flow, dipstick, flow-through and column tests). For each type of immunoassay, perspectives for multiple analyte application are discussed and examples cited.
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Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Imunoensaio/métodos , Micotoxinas/análise , Análise de Alimentos/normas , Imunoensaio/normasRESUMO
Data on influence of Francisella tularensis C-complex preparations on formation of immunity against tularemia are presented. Study of cellular immunity characteristics as well as dynamics of antibody response was carried out on white mice and guinea pigs models. Absence of toxicity, pyrogenicity, and negative effects on immunocompetent cells in combination with protective activity points to possibility of use the C-complex as a component of a subunit vaccine.
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Vacinas Bacterianas/imunologia , Francisella tularensis/imunologia , Tularemia/imunologia , Tularemia/prevenção & controle , Vacinação , Animais , Anticorpos Antibacterianos/sangue , Apoptose , Proteínas de Bactérias/imunologia , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/toxicidade , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos , Cobaias , Ativação Linfocitária , Proteínas de Membrana/imunologia , Camundongos , Baço/fisiologia , Timo/fisiologia , Tularemia/sangue , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/toxicidadeRESUMO
A new homogeneous fluoroimmunoassay method based on the use of dynamic long-wavelength fluorescence polarization is presented here for the first time. This methodology, which is applied to the determination of linear alkylbenzenesulfonates (LASs) in water samples, involves the use of a new long-wavelength tracer synthesized from the oxazine dye Nile Blue (NB) via a carbodiimide method. This tracer exhibits fluorescent properties at lambda(ex) 626 and lambda(em) 674nm. The variation of fluorescence polarization with time is followed using the T-format configuration of the spectrofluorimeter and the analytical parameter used is the initial rate, which is measured in only 0.7s. The dynamic range of the calibration graph is 0.05-4.7mg/L, with a detection limit of 0.03mg/L. The precision, expressed as relative standard deviation was assayed at 0.05 and 1mg/L, giving values in the range 7.6-9.1%. Other anionic, cationic and non-ionic surfactants were tolerated at much higher concentration levels than that of the analyte. The method has proven its practical usefulness for the analysis of water samples, in which only a solid phase extraction step is necessary. Recoveries ranged from 80.8 to 119.8%, with a mean value of 100.8%.