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1.
Adv Clin Chem ; 92: 1-57, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31472751

RESUMO

Immunosensors are compact tools on which antibody and antigen interactions are formed. The specific interaction between antibody and antigen is detected by using a transducer and an electrical signal is measured. This specific interaction between these molecules makes immunosensor very attractive for several applications in different fields. Electrochemical immunosensors are successful devices in selective and sensitive detection of several analytes. Electrochemical transducing methods such as voltammetric, potentiometric, conductometric or impedimetric have been utilized in different applications due to their excellent properties such as being low-cost, sensitivity and simplicity. In this chapter, the fundamentals of electrochemical immunosensors are summarized and different applications in food, environmental and clinical analyses are investigated and discussed.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Humanos , Imunoensaio
2.
Rev Bras Parasitol Vet ; 28(3): 518-521, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31482939

RESUMO

The objective of this study was to report an outbreak of human toxoplasmosis at a research institution in Londrina, Paraná, from December 2015 to February 2016. Blood samples from 26 symptomatic individuals were collected and the microparticle chemiluminescence immunoassay was performed to detect IgM, IgG and specific IgG avidity test in the official laboratory. A total of 20 people with symptoms and serology compatible with acute toxoplasmosis (IgM positive and IgG with low avidity) were selected as cases, while 45 asymptomatic employees working in the same teams and during the same shifts were selected as controls. All the participants of the investigation answered an epidemiological questionnaire. Three samples of water and one sludge from the institution's supply cisterns, 10 soil samples, 11 plant samples, three cat fecal samples and one domestic feline cadaver were collected for analysis of the polymerase chain reaction (PCR) for T. gondii. After analyzing the epidemiological data, the consumption of vegetables in the restaurant of the institution was the only variable associated with the occurrence of the disease. In laboratory results, all the samples showed negative results to PCR. The rapid recognition of the outbreak, early notification and investigation could have broken the chain of transmission early, thus preventing the emergence of new cases. In addition, the adoption of good food handling practices could have prevented the occurrence of the outbreak.


Assuntos
Anticorpos Antiprotozoários/sangue , Surtos de Doenças , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Toxoplasma/imunologia , Toxoplasmose/epidemiologia , Adulto , Idoso , Animais , Brasil/epidemiologia , Estudos de Casos e Controles , Gatos , Feminino , Humanos , Imunoensaio , Luminescência , Masculino , Pessoa de Meia-Idade , Fatores de Risco
3.
Chem Commun (Camb) ; 55(69): 10312-10315, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31397446

RESUMO

Herein, we report a novel magnet-mediated antibody-boronate sandwich-typed assay (ABSTA) strategy for the ultrasensitive, specific, rapid, and enzyme-free detection of glycoproteins in complex samples. The proposed ABSTA method exhibited ultrahigh sensitivity for HCG with a detection limit of 0.19 mIU mL-1, which is approximately 40-fold lower than that of conventional sandwich enzyme immunoassay.


Assuntos
Anticorpos Imobilizados/química , Ácidos Borônicos/química , Gonadotropina Coriônica/sangue , Corantes Fluorescentes/química , Imãs/química , Anticorpos Monoclonais/química , Gonadotropina Coriônica/análise , Fluorescência , Humanos , Imunoensaio/métodos , Limite de Detecção
4.
Biochem Med (Zagreb) ; 29(3): 030702, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31379460

RESUMO

Introduction: Measurement of parathyroid hormone (PTH) is essential in the investigation and management of calcium metabolism disorders. To assess the significance of any assay result when clinical decision making biological variation (BV) of the measurand must be taken into consideration. The aim of the present study is determining the BV parameters for serum PTH. Materials and methods: Blood samples were taken at weekly intervals from 20 healthy subjects for ten weeks in this prospective BV study. Serum "intact PTH" concentrations were measured with electrochemiluminescence method. Biological variation parameters were estimated using the approach proposed by Fraser. Results: The values of within-subject biological variation (CVI), between-subject biological variation (CVG), analytical variation (CVA), reference change value (RCV) and individuality index (II) for serum PTH were 21.1%, 24.9%, 3.8%, 59.4% and 0.8%, respectively. Within-subject biological variation and CVG were also determined according to gender separately; 18.5% and 24.0%; 26.2% and 18.6% for male and female, respectively. Calculated desirable precision and bias goals were < 10.6% and < 6.3%, respectively. Conclusion: This study may contribute to BV data on serum PTH as it includes a sufficient number of volunteers from both genders over an acceptable period of time. We do not recommend the usage of population-based reference intervals for serum PTH concentrations. Reference change value may be helpful for the evaluation of serial serum PTH results. Nonetheless, evaluation of data according to gender is necessary when setting analytical performance specifications.


Assuntos
Hormônio Paratireóideo/sangue , Adulto , Feminino , Voluntários Saudáveis , Humanos , Imunoensaio/normas , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/normas , Estudos Prospectivos , Valores de Referência
5.
Ecotoxicol Environ Saf ; 182: 109473, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31398783

RESUMO

Clenbuterol (CLEN) is a sympathomimetic amine used as a decongestant and bronchodilator while treating breathing disorders. It is also used in food-producing animals as it improves the rate of red meat production. However, it is prohibited in many countries nowadays due to human health and safety concerns. Unfortunately, the illegal use of CLEN is still rampant. Thus, monitoring it in food and livestock is important. Here, we report a novel murine antibody and an open sandwich enzyme linked immunosorbent assay (OS-ELISA) to detect CLEN based on antigen-antibody reactions. The genes of antibody variable regions in mice immunized with CLEN conjugated with bovine serum albumin were cloned into a phagemid (pDong1/Fab) to construct a phage-display antibody library, from which a novel antibody, A12, was selected. Then, an OS-ELISA was developed to detect CLEN using separated variable regions of the A12 antibody. The limit of detection of the assay was found to be 8 ng/mL, which was useful for monitoring CLEN usage.


Assuntos
Clembuterol/análise , Ensaio de Imunoadsorção Enzimática , Animais , Anticorpos , Humanos , Imunoensaio , Camundongos , Soroalbumina Bovina
6.
Acta Vet Scand ; 61(1): 38, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31391084

RESUMO

Canine leishmaniosis is a disease caused by Leishmania infantum, a vector-borne parasite. Due to the zoonotic potential of canine leishmaniosis, infected dogs must be identified. Serological assays are the most common methods for the detection of L. infantum infection in dogs used in veterinary practice. The aim of the study was to assess the performance of a rapid immunochromatographic test (FASTest LEISH®, MEGACOR Diagnostik) for the detection of specific antibodies to that of the L. infantum in dog sera. The results were simultaneously compared using a commercial brand of indirect immunofluorescence antibody test and an in-house enzyme-linked immunosorbent assay as references. Between the two reference tests, 232 serum samples out of 244, produced concordant results while 12 exhibited discordant results. Of the 232 concordant samples, 121 were classified as L. infantum seropositive, and 111 samples were previously classified as L. infantum seronegative by a combination of the reference assays. All samples that were seropositive by the reference tests were also positive according to the rapid test, and only one sample that was seronegative according to the two reference assays was positive according to the rapid test. Compared with the reference tests, the rapid test sensitivity was 100%, specificity was 99.1%, accuracy was 99.6%, Cohen's kappa coefficient was 0.99, and the area under receiver operating characteristic curve was 0.995. The FASTest LEISH® is a rapid, qualitative in-clinic test with high sensitivity and specificity.


Assuntos
Anticorpos Antiprotozoários/sangue , Doenças do Cão/diagnóstico , Ensaio de Imunoadsorção Enzimática/veterinária , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Imunoensaio/veterinária , Leishmaniose Visceral/veterinária , Animais , Doenças do Cão/sangue , Cães , Leishmania infantum , Leishmaniose Visceral/sangue , Leishmaniose Visceral/diagnóstico , Sensibilidade e Especificidade
7.
Analyst ; 144(17): 5108-5116, 2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31373337

RESUMO

We report here the influence of antibody immobilization strategy for protein immunosensors on screen printed carbon electrode arrays in terms of antibody binding activity, analytical sensitivity, limit of detection, and stability. Horseradish peroxidase (HRP) was the model analyte with anti-HRP immobilized on the sensors, and HRP activity was used for detection. Covalently immobilized anti-HRP antibodies on electrodes coated with chitosan, electrochemically reduced graphene oxide (rGO), and dense gold nanoparticle (AuNP) films had only 20-30% of the total immobilized antibodies active for binding. Active antibodies increased to 60% with passively adsorbed antibodies on bare electrodes, to 85% with oriented antibodies using protein A covalently immobilized on AuNP-coated carbon electrode, and to 98% when attached to protein A passively adsorbed onto bare electrodes. Passively adsorbed antibodies on bare electrodes lost activity in 1-2 days, but antibodies immobilized using other strategies remained relatively stable after 5 days. Covalent immobilization gave limits of detection (LOD) of 40 fg mL-1, while passively adsorbed antibodies or protein A on carbon electrodes had LODs 4-8 fg mL-1, but were unstable. Sensitivity was highest for antibodies covalently attached to AuNP electrodes (2.40 nA per log pg per mL) that also had highest antibody coverage, and decreased slightly when protein A on AuNP was used to orient antibodies. Passively adsorbed antibodies and oriented antibodies on protein A gave slightly lower sensitivities. Immobilization strategy or antibody orientation did not have a significant effect on LOD, but dynamic range increased as the number of active antibodies on sensor surfaces increased.


Assuntos
Anticorpos Imobilizados/química , Carbono/química , Técnicas Biossensoriais/métodos , Quitosana/química , Técnicas Eletroquímicas/métodos , Eletrodos , Grafite/química , Peroxidase do Rábano Silvestre/química , Imunoensaio/métodos , Limite de Detecção , Oxirredução , Propriedades de Superfície
8.
Tumour Biol ; 41(7): 1010428319860728, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31264534

RESUMO

Colon cancer represents one of the most common cancers in the world. Despite improved treatment, mortality remains high. In order to improve the assessment of prognosis for colon cancer patients, identifying new prognostic markers remains necessary. We analyzed preoperative serum samples from 148 colon cancer patients surgically treated at Helsinki University Hospital from 1998 through 2002 using a multiplex proximity extension assay (Oncology II panel, Olink Bioscience, Uppsala, Sweden), a panel constituting 92 immunological and oncological markers. We performed univariate and multivariate analyses on these patients and calculated the disease-specific survival among patients using the log-rank test for Kaplan-Meier estimates. In the univariate survival analysis of 92 biomarkers, 26 resulted in p < 0.1. Among these, eight biomarkers emerged as statistically significant (p < 0.05). Patients with low levels of kallikrein 13 had a poor prognosis. Moreover, patients with high levels of amphiregulin, carcinoembryonic antigen-related adhesion molecule 5, interleukin 6, mucin 16, syndecan 1, transforming growth factor alpha, and vimentin also had a poor prognosis. In the multivariate analysis, kallikrein 13 and mucin 16 emerged as independent prognostic markers. The role of kallikrein 13, a member of the serine protease kallikrein biomarker family, in tumorigenesis remains unclear. Mucin 16 is also known as carbohydrate antigen 125, a well-known ovarian cancer biomarker. Patients with low levels of kallikrein 13 (hazard ratio: 0.36; 95% confidence interval: 0.14-0.92; p = 0.033) and high levels of mucin 16 (hazard ratio: 3.15; 95% confidence interval: 1.68-5.93; p < 0.005) had a poor prognosis. Mucin 16 and kallikrein 13 represent independent prognostic markers for colon cancer. Furthermore, the clinical utility of mucin 16 and kallikrein 13 serum tests warrants additional investigation.


Assuntos
Antígeno Ca-125/metabolismo , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Calicreínas/metabolismo , Proteínas de Membrana/metabolismo , Idoso , Biomarcadores Tumorais/metabolismo , Feminino , Humanos , Imunoensaio/métodos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Análise de Sobrevida
9.
J Agric Food Chem ; 67(32): 9022-9031, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31339724

RESUMO

The quantitative multiplex immunochromatographic assay (mICA) has received an increasing amount of attention in multitarget detection. However, the quantitative results in the reported mICAs were obtained by recording the signals on the test lines that with which various analyte-independent factors readily interfere, resulting in inaccurate quantitation. The ratiometric strategy using the T/C value (ratios of signals on the test line to those of the control line) for signal correction can effectively circumvent these issues to enable more accurate detection. Herein, we present for the first time a novel ratiometric mICA strip with multiple T lines for the simultaneous quantitative detection of aflatoxin B1 (AFB1), fumonisin B1 (FB1), and ochratoxin A (OTA) using highly luminescent quantum dot nanobeads (QBs) as enhanced signal reporters. To achieve reliable ratiometric signal output, a biotin-streptavidin system was introduced to replace the conventional anti-mouse IgG antibody for reliable reference signals on the control line that are completely independent of the signal probe and analyte. By using stable T/C values as quantitative signals, our proposed QB-mICA method can successfully detect three mycotoxins with concentrations as low as 1.65 pg/mL for AFB1, 1.58 ng/mL for FB1, and 0.059 ng/mL for OTA. The detection performance of the developed QB-mICA strip, including precision, specificity, and reliability, was further evaluated using artificially contaminated cereal samples. The results demonstrate the improved accuracy and reliability of quantitative determination by comparison with the anti-mouse IgG antibody. Thus, this work provides a promising strategy for developing a ratiometric mICA method for accurately quantifying multiple analytes using the biotin-SA system, opening up a new direction in quantitative mICAs.


Assuntos
Aflatoxina B1/análise , Fumonisinas/análise , Imunoensaio/métodos , Ocratoxinas/análise , Animais , Biotina/química , Grão Comestível/química , Contaminação de Alimentos/análise , Imunoensaio/instrumentação , Luminescência , Camundongos , Micotoxinas , Pontos Quânticos , Estreptavidina/química
10.
J Agric Food Chem ; 67(32): 9096-9103, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31356079

RESUMO

A monoclonal antibody (mAb) was raised against tebuconazole (TEB) using a hapten where the p-chloro substituent of the TEB molecule was replaced with a long-chain carboxylic acid. The resulting mAb showed high sensitivity and specificity against TEB characterized by ELISA with a half-maximal inhibitory concentration (IC50) of 0.19 ng mL-1 and with cross-reactivity (CR) values below 0.01% to several analogues of triazole fungicides. On the basis of the mAb produced, a quantum dot beads-based fluorescence immunochromatographic test strip assay (QBs-FITSA) was developed for rapid and sensitive detection of TEB in agricultural product samples. The QBs-FITSA exhibited a linear detection range from 0.02 to 1.25 ng mL-1 with a limit of detection (LOD) of 0.02 ng mL-1. Furthermore, using produced mAb, multiple high-throughput rapid immunoassay formats could be achieved as a convenient monitoring tool for evaluation of human and environmental exposure to TEB.


Assuntos
Brassica/química , Cucumis sativus/química , Fungicidas Industriais/análise , Imunoensaio/métodos , Triazóis/análise , Triticum/química , Anticorpos Monoclonais/análise , Contaminação de Alimentos/análise , Fungicidas Industriais/isolamento & purificação , Imunoensaio/instrumentação , Limite de Detecção , Pontos Quânticos/química , Triazóis/isolamento & purificação
11.
Phys Chem Chem Phys ; 21(28): 15787-15797, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31282520

RESUMO

With the aim of improving the reproducibility of capacitive immunosensors, we performed a comparative study of four different insulating/immobilization chemistries. Each chemistry targeted different areas of an interdigitated electrode including an alkyl thiol monolayer on the electrode surface, an amino silane monolayer on the gaps between electrodes, and conformal coatings via passive adsorption of the probe and a spin-coated layer of poly(methyl methacrylate) (PMMA). We analyzed the dielectric properties of these chemistries by comparing their capacitive behavior through equivalent circuit modeling and correlate the observed behavior with their surface characteristics by using atomic force microscopy and finite element modeling. We found that surface binding events occurring in the interdigitated electrode gaps play a major role in the overall change in capacitance. This was confirmed via finite element modeling showing an increased electric field intensity in the electrode gaps by 14%, compared to directly above the electrodes. Among the investigated surface chemistries, PMMA conformal coating produced a smooth surface (Rq roughness = 0.21 ± 0.02 nm) providing the most reproducible and stable capacitance change (15.6 ± 0.4%) in response to specific antigen-antibody binding.


Assuntos
Técnicas Biossensoriais/instrumentação , Eletrodos , Imunoensaio/instrumentação , Capacitância Elétrica , Microscopia de Força Atômica , Modelos Químicos , Ligação Proteica
12.
Chem Commun (Camb) ; 55(68): 10060-10063, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31328750
13.
Environ Monit Assess ; 191(8): 507, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31342281

RESUMO

Glyphosate is the most widespread herbicide and its global use is steadily increasing. Although glyphosate is considered to have low toxicity, its wide application has raised concerns about its effects on human health. The extensive use of glyphosate has risen a need of its continuous monitoring in drinking and surface waters to assure in accordance with the set standards. Within the present study, we have developed a novel assay for the on-site detection of glyphosate by combining flow-through technology with the high specificity of immunorecognition. The proposed biosensing system was based on the detection of fluorescence signal generated by the quantitative replacement of glyphosate in antigen-antibody complex with IgY-type anti-glyphosate antibodies on microbeads by synthetic 5-carboxytetramethylrhodamine (5-TAMRA) conjugated glyphosate. The working range of this assay was in low millimolar range and the time required for glyphosate detection around 0.5 h. The applicability of the immunoassay for glyphosate detection in surface water was tested and the biosensor results were validated with high-performance liquid chromatography.


Assuntos
Técnicas Biossensoriais/métodos , Monitoramento Ambiental/métodos , Glicina/análogos & derivados , Herbicidas/análise , Glicina/análise , Humanos , Imunoensaio , Reprodutibilidade dos Testes , Fatores de Tempo , Poluentes Químicos da Água
14.
Anal Chim Acta ; 1078: 151-160, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31358213

RESUMO

Herein, we report a new signal amplification scheme for quantitative biochemical analysis based on gold nanoparticle (GNPs) catalyzed polymerization of transparent silane solution to milky white and turbid siloxane. Using immunoassay as a proof of concept, GNP labeled immunoprobe was used to bind captured antigen and catalyse the polymerization reaction allowing sensitive biochemical investigation. The polymerization reaction was optimized for standard 96 well polystyrene microtiter plates and we discovered that sodium lactate acts as an enhancer in the polymerization reaction as it reduces detection time to merely 30 min. The sensing strategy was applied to detection and quantification of Salmonella Typhimurium in water and egg samples and the platform showed excellent visibly quantifiable analytical response up to 100 cells mL-1. Furthermore, clinical utility and potential of the method was validated by detecting Vi capsular polysaccharide (Vi antigen) responsible for typhoidal Salmonellosis in human serum in sandwich format with a detection limit of 1 ng mL-1. The method serves as the first report towards nanoparticle triggered polymerization for development of rapid and low cost quantitative biochemical assay.


Assuntos
Ouro/química , Imunoensaio/métodos , Nanopartículas Metálicas/química , Polissacarídeos Bacterianos/sangue , Salmonella typhimurium/isolamento & purificação , Siloxanas/síntese química , Animais , Anticorpos/imunologia , Galinhas , Água Potável/microbiologia , Ovos/microbiologia , Contaminação de Alimentos/análise , Humanos , Limite de Detecção , Tamanho da Partícula , Polimerização , Polissacarídeos Bacterianos/imunologia , Estudo de Prova de Conceito , Salmonella typhimurium/imunologia , Silanos/química , Temperatura Ambiente
15.
Adv Exp Med Biol ; 1140: 649-664, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31347077

RESUMO

Determination of concentration of cortisol in various biological fluids can provide extensive information about a person's health. Historically, cortisol and its derivatives were (and still are) determined using immunoaffinity-based methods such as colorimetric ELISA assay, chemiluminescent immunoassay, fluorescence assays, radioimmunoassay, electrochemiluminescence immunoassay, immunochromatographic test, or sensors and immunosensors. Recently, mass spectrometry (MS)-based methods started to be used in determination of cortisol and its derivatives. These MS methods are net superior to immunoaffinity-based assays, but are not easily applicable and are also time-consuming and price prohibitive. Furthermore the standard MS instruments used are triple quadrupole instruments. Here we review the literature on the MS and non-MS based methods for determination of cortisol and its derivatives and also explore the use of a less used quadrupole-time of flight instrument in determination of these compounds.


Assuntos
Hidrocortisona/análise , Espectrometria de Massas , Humanos , Imunoensaio
16.
Int J Nanomedicine ; 14: 4293-4307, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354261

RESUMO

Purpose: Antibodies are key reagents in the development of immunoassay. We attempted to develop high-performance CPP immunoassays using high-affinity monoclonal antibodies prepared via cytokine-assisted immunization. Methods: We used fetal liver tyrosine kinase 3 ligand (Flt3L), CC subtype chemokine ligand 20 (CCL20), and granulocyte-macrophage colony-stimulating factor (GM-CSF) to assist traditional subcutaneous immunization of preparing high-affinity monoclonal antibodies, and further to develop high-performance immunoassay methods for CPP. Results: This novel immune strategy significantly enhanced immune response against CPP. Six anti-CPP monoclonal antibodies (mAbs) with high affinity were successfully screened and selected for application in a fully automated magnetic chemiluminescence immunoassay (CLIA). This robust and rapid assay can efficiently detect CPP in the range of 1.2-1250 pmol L-1 with a detection limit of 6.25 pmol L-1. Significantly, the whole incubation process can be completed in 30 min as compared to about 4.5 hr for the control ELISA kit. Furthermore, this assay exhibited high sensitivity and specificity, low intra-assay and inter-assay coefficients of variation (CVs < 15%). The developed assay was applied in the detection of CPP in 115 random serum samples and results showed a high correlation with data obtained using a commercially available ELISA kit (correlation coefficient, 0.9737). Conclusion: Our assay could be applied in the point-of-care testing of CPP in the serum samples, and also the method developed in this study could be adopted to explore the detection and diagnosis of other biomarkers for various diseases.


Assuntos
Anticorpos Monoclonais/imunologia , Citocinas/metabolismo , Glicopeptídeos/sangue , Imunização , Imunoensaio/métodos , Medições Luminescentes/métodos , Testes Imediatos , Animais , Anticorpos Monoclonais/biossíntese , Feminino , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Nanopartículas de Magnetita/química , Camundongos Endogâmicos BALB C , Sensibilidade e Especificidade
17.
N Engl J Med ; 381(1): 47-54, 2019 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-31269365

RESUMO

A 37-year-old man with a history of seminoma presented with vertigo, ataxia, and diplopia. An autoantibody specific for kelch-like protein 11 (KLHL11) was identified with the use of programmable phage display. Immunoassays were used to identify KLHL11 IgG in 12 other men with similar neurologic features and testicular disease. Immunostaining of the patient's IgG on mouse brain tissue showed sparse but distinctive points of staining in multiple brain regions, with enrichment in perivascular and perimeningeal tissues. The onset of the neurologic syndrome preceded the diagnosis of seminoma in 9 of the 13 patients. An age-adjusted estimate of the prevalence of autoimmune KLHL11 encephalitis in Olmsted County, Minnesota, was 2.79 cases per 100,000 men. (Funded by the Rochester Epidemiology Project and others.).


Assuntos
Autoanticorpos/análise , Encéfalo/imunologia , Proteínas de Transporte/imunologia , Técnicas de Visualização da Superfície Celular , Encefalite/imunologia , Doença de Hashimoto/imunologia , Síndromes Paraneoplásicas do Sistema Nervoso/imunologia , Seminoma/complicações , Neoplasias Testiculares/complicações , Adulto , Idoso , Encefalite/epidemiologia , Doença de Hashimoto/epidemiologia , Humanos , Imunoensaio , Masculino , Pessoa de Meia-Idade , Minnesota/epidemiologia , Prevalência
18.
Environ Sci Pollut Res Int ; 26(23): 23471-23479, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31197672

RESUMO

A rapid and sensitive immunoassay for the simultaneous detection of imidacloprid and thiacloprid was developed by using magnetic nanoparticles (MNPs) and upconversion nanoparticles (UCNPs). The UCNPs of NaYF4:Yb, Er and NaYF4:Yb, Tm were synthesized and conjugated with anti-imidacloprid monoclonal antibody (mAb) and anti-thiacloprid mAb as signal labels, while the MNPs were conjugated with antigens of thiacloprid and imidacloprid as separation elements. The fluorescence intensities of Yb/Er- and Yb/Tm-doped UCNPs were detected simultaneously in 544 nm and 477 nm under the excitation of NIR light (980 nm). The amounts of mAb-conjugated UCNPs that were separated by antigen-conjugated MNPs were determined based on competitive immunoassays. Under the optimal conditions, the 50% inhibiting concentration (IC50) and limit of detection (LOD, IC10) were 5.80 and 0.32 ng/mL for imidacloprid and 6.45 and 0.61 ng/mL for thiacloprid, respectively. The immunoassay exhibited negligible cross-reactivity with analogs of imidacloprid and thiacloprid except imidaclothiz (86.2%). The average recoveries of imidacloprid and thiacloprid in environmental and agricultural samples, including paddy water, soil, pears, oranges, cucumbers, and wheat, ranged from 78.4 to 105.9% with relative standard deviations (RSDs) of 2.1-11.9% for imidacloprid and ranged from 82.5 to 102.3% with RSDs of 1.0-16.5% for thiacloprid. In addition, the results of the immunoassay correlated well with high-performance liquid chromatography for the detection of the authentic samples.


Assuntos
Imunoensaio/métodos , Nanopartículas de Magnetita/química , Neonicotinoides/análise , Nitrocompostos/análise , Tiazinas/análise , Fluorescência , Magnetismo , Nanopartículas/química , Tiazóis
19.
Int Arch Allergy Immunol ; 180(1): 28-36, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31189157

RESUMO

BACKGROUND: Clinically meaningful specific IgE determination is an important step in the diagnosis of allergic diseases. While patient's history and skin prick tests are available during the medical visit, most IgE immunoassays require hours to several days to be available. Recent developments in the field of nanofluidic technology open new horizons for point-of-care management of this unmet medical need. OBJECTIVE: This study aimed to compare IgE diagnostic agreement between a nanofluidic assay (abioSCOPE®) and a laboratory reference method (Phadia Laboratory System®) in a real-world clinical setting. METHODS: Sera from 105 patients whose routine allergy diagnostic workup required a blood sampling were used to compare the novel nanofluidic IgE assay to a reference method in a blind manner for a panel of five respiratory allergens. To assess the agreement between methods, patient records were reviewed by four independent experts to establish the final diagnosis. Experts were blinded to the IgE serological method used, but had access to patient history, skin prick tests, and blood test results. RESULTS: Analytic agreement between the two methods was 81% for the tested panel of allergens (ranging from 77 to 89%). The overall agreement in clinical diagnosis decision taken by the expert panel was 94.6% with the nanofluidic IgE assay when compared to the reference method. CONCLUSION: The nanofluidic IgE assay, as determined through an evaluation based on clinical history, skin prick tests, and IgE measurement, is a valuable tool for allergy experts to identify patients' sensitization patterns at the point of care, and for routine IgE diagnostic workup.


Assuntos
Imunoensaio/métodos , Imunoensaio/normas , Imunoglobulina E/imunologia , Dispositivos Lab-On-A-Chip , Nanotecnologia/métodos , Adolescente , Adulto , Idoso , Alérgenos/imunologia , Feminino , Humanos , Hipersensibilidade/diagnóstico , Hipersensibilidade/imunologia , Imunoglobulina E/sangue , Masculino , Pessoa de Meia-Idade , Padrões de Referência , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Testes Cutâneos , Adulto Jovem
20.
Zhonghua Xue Ye Xue Za Zhi ; 40(5): 411-416, 2019 May 14.
Artigo em Chinês | MEDLINE | ID: mdl-31207707

RESUMO

Objectives: To assess the diagnostic values of latex immunoturbidimetric assay (LIA) and particle immunofiltration assay (PIFA) for heparin-induced thrombocytopenia (HIT) . Methods: Samples from 94 patients with suspected HIT from May 2016 to July 2018 in our hospital were prospectively analyzed by the two immunoassays. Their medical records and further follow-up data were also collected and analyzed by our hematologists to make the 4Ts scores and confirm the diagnosis of HIT, respectively. Performance characteristics of the two immunoassays were assessed, including sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) . Their post-test probabilities (PTP) were also calculated based on the 4Ts score. Results: Among 94 cases, 15 (16.0%) had a positive HIT, including 6 of 37 (16.2%) with an intermediate, and 9 of 15 (60.0%) with a high 4Ts score. PIFA operating characteristics were: sensitivity 100.0% (15/15) , specificity 51.9% (41/80) , PPV 28.3% (15/53) , NPV 100.0% (41/41) . The positive PTP in intermediate and high 4Ts score group were 28.7% and 75.7%, respectively, while negative PTP were all 0. At manufacturers' cutoffs, LIA operating characteristics were: sensitivity 66.7% (10/15) , specificity 94.9% (75/79) , PPV 71.4% (10/14) and NPV 93.8% (75/80) . The positive and negative PTP in intermediate 4Ts score group were 71.8% and 6.3%, while 95.2% and 34.4% in high 4Ts score group, respectively. Receiver operating characteristic (ROC) analysis manifested that LIA was preferable than PIFA, and combining the 2 assays together was significantly better than single test. Conclusions: 4Ts score is still an important tool for the diagnosis of HIT. Combining clinical score with heparin/PF4 antibody assay can increase the accuracy of confirming or excluding HIT. Although PIFA is inferior to LIA in the diagnostic value, its user friendliness and 100% NPV have major advantages. Combining the 2 assays together can achieve a higher diagnostic value.


Assuntos
Heparina/efeitos adversos , Trombocitopenia , Anticorpos , Anticoagulantes , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoensaio , Fator Plaquetário 4 , Trombocitopenia/induzido quimicamente
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