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1.
Biosens Bioelectron ; 176: 112942, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33401144

RESUMO

2019 novel coronavirus (2019-nCoV) with strong contagion in the crowd, has ravaged worldwide and severely impacts the human health and epidemic prevention system, by producing a series of significant stress reactions in the body to induce further cytokine storm. Transcription factors (TFs) served as essential DNA binding proteins play an integral role in regulating cytokine storm, and the detection of it in the human coronavirus environment provides especially valuable approaches to diagnosis and treatment of 2019-nCoV and development of antiviral drugs. In this work, an entropy-driven electrochemiluminescence (ECL) biosensor was constructed for ultra-sensitive bioassay of NF-κB p50. The strategy primarily capitalizing the splendid double-stranded DNA (dsDNA) binding properties of transcription factors, employing GOAu-Ru composite material as ECL emitter, utilizing entropy-driven reactions for signal amplification method, offered a repeatable proposal for TFs detection. In the absence of TFs, the released DNA1 further went in the entropy-driven reaction, contributing to an "ECL off" state. However, in the presence of TFs, the dsDNA avoided being digested, which blocked DNA1 for participating in the entropy-driven reaction, and the system exhibited an "ECL on" state. Most importantly, the ECL bioanalytical method denoted broad application prospects for NF-κB p50 detection with a lower detection limit (9.1 pM).


Assuntos
Técnicas Biossensoriais/métodos , Síndrome da Liberação de Citocina/imunologia , Subunidade p50 de NF-kappa B/análise , Técnicas Biossensoriais/estatística & dados numéricos , Síndrome da Liberação de Citocina/etiologia , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/estatística & dados numéricos , Entropia , Humanos , Limite de Detecção , Medições Luminescentes/métodos , Medições Luminescentes/estatística & dados numéricos , Pandemias , Sensibilidade e Especificidade
2.
Ecotoxicol Environ Saf ; 207: 111554, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33254411

RESUMO

Toxicity monitoring of environmental pollutants especially petroleum hydrocarbons as priority pollutants is an important environmental issue. This study addresses a rapid, sensitive and cost effective method for the detection of total petroleum hydrocarbons (TPHs) using Aliivibrio fischeri bioluminescence inhibition bioassay. At the first step, the optimum conditions including time, pH and temperature for growth of A. fischeri were determined. Then, two methods were used to evaluate the toxicity of petroleum compounds. In the first method, short-term (15 min) and long-term (16 h) toxicity assays were performed. In the second method luminescence kinetics of A. fischeri was investigated during 24 h. The results demonstrated the most appropriate time for the bacterial growth occurred 16 h after inoculation and optimum temperature and pH were found 25 °C and 7, respectively. Short-term and long-term toxicity did not indicate any toxicity for various concentrations of TPHs (30, 50, 110, 160, 220 mg/L). Considering the luminescence kinetics of A. fischeri the long-term assay was introduced as 6 h. The half maximal effective concentration (EC50) was achieved 1.77 mg/L of TPHs. It is concluded that the luminescence kinetics of A. fischeri can be a valuable approach for assessing toxicity of TPHs in aquatic environments.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Petróleo/toxicidade , Poluentes Químicos da Água/toxicidade , Bioensaio/métodos , Poluentes Ambientais/toxicidade , Hidrocarbonetos/toxicidade , Luminescência , Medições Luminescentes
3.
Biosens Bioelectron ; 172: 112765, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33126179

RESUMO

To accurately diagnose COVID-19 infection and its time-dependent progression, the rapid, sensitive, and noninvasive determination of immunoglobulins A specific to SARS-CoV-2 (IgA) in saliva and serum is needed to complement tests that detect immunoglobulins G and M. We have developed a dual optical/chemiluminescence format of a lateral flow immunoassay (LFIA) immunosensor for IgA in serum and saliva. A recombinant nucleocapsid antigen specifically captures SARS-CoV-2 antibodies in patient specimens. A labelled anti-human IgA reveals the bound IgA fraction. A dual colorimetric and chemiluminescence detection enables the affordable and ultrasensitive determination of IgA to SARS-CoV-2. Specifically, a simple smartphone-camera-based device measures the colour signal provided by nanogold-labelled anti-human IgA. For the ultrasensitive chemiluminescence transduction, we used a contact imaging portable device based on cooled CCD, and measured the light signal resulting from the reaction of the HRP-labelled anti-human IgA with a H2O2/luminol/enhancers substrate. A total of 25 serum and 9 saliva samples from infected and/or recovered individuals were analysed by the colorimetric LFIA, which was sensitive and reproducible enough for the semi-quantification of IgA in subjects with a strong serological response and in the early stage of COVID-19 infection. Switching to CL detection, the same immunosensor exhibited higher detection capability, revealing the presence of salivary IgA in infected individuals. For the patients included in the study (n = 4), the level of salivary IgA correlated with the time elapsed from diagnosis and with the severity of the disease. This IgA-LFIA immunosensor could be useful for noninvasively monitoring early immune responses to COVID-19 and for investigating the diagnostic/prognostic utility of salivary IgA in the context of large-scale screening to assess the efficacy of SARS-CoV-2 vaccines.


Assuntos
Anticorpos Antivirais/análise , Técnicas Biossensoriais/instrumentação , /diagnóstico , /imunologia , Especificidade de Anticorpos , Técnicas Biossensoriais/métodos , /virologia , Colorimetria/instrumentação , Colorimetria/métodos , Desenho de Equipamento , Humanos , Imunoglobulina A/sangue , Imunoglobulina A Secretora/análise , Medições Luminescentes/instrumentação , Medições Luminescentes/métodos , Saliva/imunologia
4.
Int J Nanomedicine ; 15: 9975-9985, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33363367

RESUMO

Background: As two important tumor markers, vascular endothelial growth factor (VEGF) and carcinoembryonic antigen (CEA) have a great value for clinical application in the early diagnosis of cancer. Due to the complex composition of biological samples, the results from combined detection of CEA and VEGF are often taken as a comprehensive indicator in order to make an accurate judgment on a disease. However, most of the current methods can only be used to detect the content of one biomarker. Therefore, it is necessary to explore a simple, rapid, low-cost, and highly sensitive method for the simultaneous detection of CEA and VEGF. Methods: Based on specific aptamers and magnetic separation, a time-resolved chemiluminescence enzyme-linked aptamer assay was developed for the simultaneous detections of CEA and VEGF in serum samples. Results: Under the optimal conditions, the linear range of the calibration curve for VEGF was from 0.5 to 80 ng mL-1, and the limit of detection was 0.1 ng mL-1. The linear range of the calibration curve for CEA was 0.5 to 160 ng mL-1, and the limit of detection was 0.1 ng mL-1. The established method was applied to detect VEGF and CEA in serum samples. The results were consistent with those of commercial kits. Conclusion: The method has high sensitivity and can quickly obtain accurate results, which could greatly improve the measurement efficiency, reduce the cost, and also reduce the volume of sample consumed. It can be seen that the method established in this study has important application value and broad application prospect in clinical diagnosis.


Assuntos
Aptâmeros de Peptídeos/metabolismo , Antígeno Carcinoembrionário/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Medições Luminescentes , Fator A de Crescimento do Endotélio Vascular/sangue , Fosfatase Alcalina/metabolismo , Biocatálise , Calibragem , Peroxidase do Rábano Silvestre/metabolismo , Humanos , Cinética , Medições Luminescentes/métodos , Fenômenos Magnéticos , Fatores de Tempo
5.
BMC Ophthalmol ; 20(1): 491, 2020 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-33371882

RESUMO

BACKGROUND: The purpose of the study was to explore the immunological components that are responsible for the proliferative alterations in the different forms of retinal detachment (RD). METHODS: Vitreous fluids were collected during 23G pars plana vitrectomy from 54 eyes of 54 patients with different RD types, such as rhegmatogenous RD (RRD) without proliferative vitreoretinopathy (PVR) (n = 30), PVR (n = 16) and proliferative diabetic retinopathy (PDR) with tractional RD (n = 8). Vitreous fluids were obtained from 19 eyes with epiretinal membrane (ERM), which were used as control samples. A multiplex chemiluminescent immunoassay was performed to evaluate the concentrations of 48 cytokines, chemokines and growth factors. RESULTS: The expression levels of eotaxin, IFN-gamma, IL-6, IL-8, IL-16, MCP-1, MIF and MIP-1 beta were significantly higher in all RD groups than in the ERM group. The levels of CTACK, IP-10, SCGF-beta, and SDF-1 alpha were significantly higher in patients with diabetic tractional RD and PVR than in other patients. The upregulation of VEGF and IL-18 was detected in PDR. CONCLUSIONS: Our results indicate that complex and significant immunological mechanisms are associated with the pathogenesis of different forms of RD: selected cytokines, chemokines and growth factors are upregulated in the vitreous of eyes with RD. The detected proteins are present in different concentrations both in RRD and PVR. In the presence of PVR and PDR, the majority of cytokines are upregulated; thus, they may serve as biomarkers to estimate the progression or severity level of proliferation and later to develop personalized therapeutic strategies to slow down or prevent pathological changes.


Assuntos
Biomarcadores/metabolismo , Citocinas/metabolismo , Retinopatia Diabética/metabolismo , Descolamento Retiniano/metabolismo , Vitreorretinopatia Proliferativa/metabolismo , Corpo Vítreo/metabolismo , Idoso , Retinopatia Diabética/cirurgia , Feminino , Humanos , Medições Luminescentes , Masculino , Pessoa de Meia-Idade , Descolamento Retiniano/cirurgia , Vitrectomia , Vitreorretinopatia Proliferativa/cirurgia
6.
Environ Monit Assess ; 192(12): 747, 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33150454

RESUMO

The inception of bioluminescence by Harvey (1952) has led to a Nobel Prize to Osamu Shimomura (Chemistry, 2008) in biological research. Consequently, in recent years, bioluminescence-based assays to monitor toxic pollutants as a real-time marker, to study various diseases and their propagation in plants and animals, are developed in many countries. The emission ability of bioluminescence is improved by gene modification, and also, search for novel bioluminescent systems is underway. Over 100 species of organisms belonging to different taxa are known to be luminous in India. However, the diversity and distribution of luminous organisms and their applications are studied scarcely in the Indian scenario. In this context, the present review provides an overview of the current understanding of various bioluminescent organisms, functions, and applications. A detailed checklist of known bioluminescent organisms from India's marine, terrestrial, and freshwater ecosystems is detailed. This review infers that Indian scientists are needed to extend their research on various aspects of luminescent organisms such as biodiversity, genomics, and chemical mechanisms for conservation, ecological, and biomedical applications.


Assuntos
Ecossistema , Monitoramento Ambiental , Animais , Organismos Aquáticos , Índia , Luciferases , Luminescência , Medições Luminescentes
7.
Biol Direct ; 15(1): 21, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-33138856

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection spreaded rapidly worldwide, as far as it has become a global pandemic. Therefore, the introduction of serological tests for determination of IgM and IgG antibodies has become the main diagnostic tool, useful for tracking the spread of the virus and for consequently allowing its containment. In our study we compared point of care test (POCT) lateral flow immunoassay (FIA) vs automated chemiluminescent immunoassay (CLIA), in order to assess their specificity and sensibility for COVID-19 antibodies detection. RESULTS: We find that different specificities and sensitivities for IgM and IgG tests. Notably IgM POCT FIA method vs CLIA method (gold standard) has a low sensitivity (0.526), while IgG POCT FIA method vs CLIA method (gold standard) test has a much higher sensitivity (0.937); further, with respect of IgG, FIA and CLIA could arguably provide equivalent information. CONCLUSIONS: FIA method could be helpful in assessing in short time, the possible contagiousness of subjects that for work reasons cannot guarantee "social distancing".


Assuntos
Infecções por Coronavirus/sangue , Pneumonia Viral/sangue , Testes Sorológicos , Sequência de Aminoácidos , Feminino , Humanos , Imunoensaio , Imunoglobulina M/metabolismo , Medições Luminescentes , Masculino , Pessoa de Meia-Idade , Pandemias , Domínios Proteicos , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo
8.
Biochem Med (Zagreb) ; 30(3): 030901, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33071558

RESUMO

Introduction: The 2019 Coronavirus disease (COVID-19) has been characterized as a pandemic, representing a serious global public health emergency. Serological tests have been proposed as reliable tools for detecting Coronavirus SARS-CoV-2 antibodies in infected patients, especially for surveillance or epidemiological purposes. The aim of this study is to evaluate the agreement between the IgM/IgG rapid assays, based on lateral flow immunochromatographic assay, and the fully automated 2019-nCoV IgM and IgG, based on chemiluminescence immunoassay. Materials and methods: SARS-CoV-2 antibodies were measured with the BIOSYNEX COVID-19 BSS IgM/IgG test (BIOSYNEX, Illkirch-Graffenstaden, France) and the MAGLUMI CLIA (IgM and IgG) (SNIBE - Shenzhen New Industries Biomedical Engineering, Shenzhen, China) in 70 serum samples from patients with PCR-confirmed diagnosis. The strength of the agreement of the two methods was calculated by using the Cohen Kappa index. Results: The results showed a good grade of concordance between the two immunoassays with a Cohen's kappa coefficient of 0.71 (95%CI: 0.54-0.87) for IgG SARS-CoV-2 antibodies and 0.70 (95%CI: 0.53-0.87) for IgM SARS-CoV-2 antibodies. In addition, the rapid assays BIOSYNEX COVID-19 BSS for detecting SARS-CoV-2 antibodies showed a positive likelihood ratio (LR) of 10.63 (95%CI: 2.79-40.57) for IgG and a LR of 6.79 (95%CI: 2.93-15.69) for IgM. Conclusion: Our results suggest that the immunochromatographic rapid IgM/IgG test and the chemiluminescence IgM and IgG immunoassay have a good degree of concordance, suggesting that both could be considered as useful tools for epidemiologic surveillance.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Pandemias , Pneumonia Viral/diagnóstico , Idoso , Feminino , Humanos , Imunoensaio , Medições Luminescentes , Masculino , Pessoa de Meia-Idade , Vigilância da População , Reprodutibilidade dos Testes
9.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 5041-5044, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019119

RESUMO

Quantitation of protein biomarker featured with portability, rapidity, high sensitivity is critical for the point-of-care testing (POCT) application. Herein, a novel smartphone-enabled microfluidic chemiluminescence platform for the quantitation of prostate specific antigen (PSA) was proposed based on acoustic tweezers approach. The primary antibodies labeled polystyrene microparticles (Ab1-PSs), target samples, the horseradish peroxidase labeled secondary antibodies (Ab2-HRP) were injected into the microfluidics simultaneously. Under the actuation of Lamb Wave Resonator (LWR), they were dynamically trapped and concentrated in the acoustic streaming; meanwhile, the biomolecular binding was enhanced. After the injection of chemiluminescent substrate, the concentrated immuno-particles catalyzed hydrogen peroxide (H2O2) reaction so that the emitted blue light was directly captured by smartphone. Besides, the flow rate and the applied power of LWR were optimized for the signal amplification. The chemiluminescence immunoassay exhibited a dynamic linear range from 0.5 ng/mL to 10 ng/mL with a limit of detection of 0.1 ng/mL in PBS buffer. The portable immunosensor will be utilized for the quantitation of PSA in serum samples to demonstrate the clinical significance.Clinical Relevance-The smartphone-enabled detection platform realizes the quantitation of biomarker within 10 min, which reveals a valuable potential tool for the early diagnosis of various diseases, even in resource-limited regions.


Assuntos
Luminescência , Smartphone , Acústica , Humanos , Peróxido de Hidrogênio , Medições Luminescentes , Masculino
10.
Clin Chim Acta ; 510: 760-766, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32910979

RESUMO

INTRODUCTION: We describe our evaluation of the Abbott SARS-CoV-2 IgG assay on the Architect immunoassay analyser. METHODS: We assessed assay precision, sensitivity, specificity, positive/negative predictive values (PPV/NPV), cross-reactivity (influenza/dengue/hepatitis B and C/rheumatoid factor/anti-nuclear/double-stranded DNA/syphilis) and sample throughput in samples from real-time polymerase chain reaction (RT-PCR) positive patients/healthcare workers (HCWs)/pre-pandemic samples. We compared the cut-off indexes (COIs) between all control samples (HCWs and pre-pandemic) to generate an optimised COI limit for reactivity. RESULTS: The assay specificity was 99.8% (n = 980) and sensitivity was 45.9-96.7% (n = 279). When tested ≥ 14 days post-positive RT-PCR (POS), the PPV/NPV was 96.4%/99.8%. The difference between the COIs of HCWs/pre-pandemic samples was small (0.01, p < 0.0001). There was minimal cross-reactivity with other antibodies. A lower COI limit for reactivity (≥0.55, using the 99th percentile COI of our controls and ROC analysis) improved diagnostic sensitivity, especially at 0-6 days POS (45.9-55.8%), with a small decrease in specificity (98.9%). The assay throughput was 100 samples in 70 min. CONCLUSION: The Abbott SARS-CoV-2 IgG assay shows excellent performance in patients ≥ 14 days POS. The difference between the COIs of HCWs and pre-pandemic samples was numerically small. A lower COI limit improves assay sensitivity with a slight decrease in specificity.


Assuntos
Betacoronavirus/imunologia , Imunoglobulina G/análise , Medições Luminescentes/métodos , Adulto , Automação , Reações Cruzadas , Feminino , Humanos , Imunoglobulina G/imunologia , Limite de Detecção , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes
11.
Clin Chim Acta ; 510: 687-690, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32910980

RESUMO

BACKGROUND: We report our findings of test performance especially specificity of a fully automated Abbott Architect anti-SARS-CoV-2 CMIA IgG and Euroimmun anti-SARS-CoV-2 ELISA IgA/IgG in human plasma. METHODS: We used positive cohort of 97 samples from Covid-19 patients or healthcare workers, collected at late time points from symptom onsets. We also included another cohort of 215 samples as negative controls, 78 of which had positive serology test results of other infectious diseases or autoimmunity. Assay specificity was assessed by using a total of 847 anonymized samples which were collected before the Covid-19 pandemic from local patient populations seeking clinical care for rheumatoid diseases, thyroid cancer, and therapeutic drug monitoring. RESULTS: Abbott IgG, Euroimmun IgG/IgA had high precision, demonstrated by both intra- and inter-day CVs of <2%. There was no Abbott or Euroimmun IgG assay cross reactivity in the 78 samples with positive serology of non-SARS-CoV-2 infectious diseases and positive autoimmune antibodies. The Abbott IgG has specificity of 99.6%, while Euroimmun IgG and IgA were as high as 91.5% and 71.5%, respectively. CONCLUSIONS: Our evaluation confirmed high specificity of the Abbott IgG assay, while it was lower for Euroimmun IgG. Euroimmun IgA has suboptimal specificity which may limit its clinical use. Assay sensitivity was high for both Abbott and Euroimmun IgG assays.


Assuntos
Betacoronavirus/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Medições Luminescentes , Humanos , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Limite de Detecção
12.
Exp Eye Res ; 200: 108253, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32949577

RESUMO

The aim of this study is to analyze the concentrations of cytokines in tear of hospitalized COVID-19 patients compared to healthy controls. Tear samples were obtained from 41 healthy controls and 62 COVID-19 patients. Twenty-seven cytokines were assessed: interleukin (IL)-1b, IL-1RA, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL9, IL-10, IL-12, IL-13, IL-15, IL-17, eotaxin, fibroblast growth factor basic, granulocyte colony-stimulating factor (G-CSF), granulocyte-monocyte colony-stimulating factor (GM-CSF), interferon (IFN)-γ, interferon gamma-induced protein, monocyte chemo-attractant protein-1, macrophage inflammatory protein (MIP)-1a, MIP-1b, platelet-derived growth factor (PDGF), regulated on activation normal T cell expressed and secreted, tumor necrosis factor-α and vascular endothelial growth factor (VEGF).In tear samples of COVID-19 patients, an increase in IL-9, IL-15, G-CSF, GM-CSF, IFN-γ, PDGF and VEGF was observed, along with a decrease in eotaxin compared to the control group (p < 0.05). A poor correlation between IL-6 levels in tear and blood was found. IL-1RA and GM-CSF were significantly lower in severe patients and those who needed treatment targeting the immune system (p < 0.05). Tear cytokine levels corroborate the inflammatory nature of SARS-CoV-2.


Assuntos
Betacoronavirus , Infecções por Coronavirus/metabolismo , Citocinas/metabolismo , Proteínas do Olho/metabolismo , Pneumonia Viral/metabolismo , Lágrimas/metabolismo , Idoso , Idoso de 80 Anos ou mais , Infecções por Coronavirus/classificação , Infecções por Coronavirus/diagnóstico , Estudos Transversais , Feminino , Hospitalização , Humanos , Imunoensaio , Inflamação/metabolismo , Ceratite/metabolismo , Medições Luminescentes , Masculino , Pessoa de Meia-Idade , Pandemias/classificação , Pneumonia Viral/classificação , Pneumonia Viral/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real , Centros de Atenção Terciária
13.
Emerg Microbes Infect ; 9(1): 2157-2168, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32940547

RESUMO

This multicenter, retrospective study included 346 serum samples from 74 patients with coronavirus disease 2019 (COVID-19) and 194 serum samples from non-COVID-19 patients to evaluate the performance of five anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody tests, i.e. two chemiluminescence immunoassays (CLIAs): Roche Elecsys® Anti-SARS-CoV-2 Test (Roche Test) and Abbott SARS-CoV-2 IgG (Abbott Test), and three lateral flow immunoassays (LFIAs): Wondfo SARS-CoV-2 Antibody Test (Wondfo Test), ASK COVID-19 IgG/IgM Rapid Test (ASK Test), and Dynamiker 2019-nCoV IgG/IgM Rapid Test (Dynamiker Test). We found high diagnostic sensitivities (%, 95% confidence interval [CI]) for the Roche Test (97.4%, 93.4-99.0%), Abbott Test (94.0%, 89.1-96.8%), Wondfo Test (91.4%, 85.8-94.9%), ASK Test (97.4%, 93.4-99.0%), and Dynamiker Test (90.1%, 84.3-94.0%) after >21 days of symptom onset. Meanwhile, the diagnostic specificity was 99.0% (95% CI, 96.3-99.7%) for the Roche Test, 97.9% (95% CI, 94.8-99.2%) for the Abbott Test, and 100.0% (95% CI, 98.1-100.0%) for the three LFIAs. Cross-reactivity was observed in sera containing anti-cytomegalovirus (CMV) IgG/IgM antibodies and autoantibodies. No difference was observed in the time to seroconversion detection of the five serological tests. Specimens from patients with COVID-19 pneumonia demonstrated a shorter seroconversion time and higher chemiluminescent signal than those without pneumonia. Our data suggested that understanding the dynamic antibody response after COVID-19 infection and performance characteristics of different serological test are crucial for the appropriate interpretation of serological test result for the diagnosis and risk assessment of patient with COVID-19 infection.


Assuntos
Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/imunologia , Imunoensaio/métodos , Medições Luminescentes/métodos , Pneumonia Viral/diagnóstico , Pneumonia Viral/imunologia , Adulto , Idoso , Anticorpos Antivirais/sangue , Betacoronavirus/genética , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Reações Cruzadas/imunologia , Feminino , Humanos , Imunoensaio/normas , Medições Luminescentes/normas , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Reprodutibilidade dos Testes , Soroconversão , Testes Sorológicos , Índice de Gravidade de Doença , Taiwan/epidemiologia
14.
PLoS One ; 15(9): e0238153, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32998160

RESUMO

Bacillus cereus is a foodborne pathogen causing emesis and diarrhea in those affected. It is assumed that the non-hemolytic enterotoxin (Nhe) plays a key role in B. cereus induced diarrhea. The ability to trace Nhe activity is important for food safety. While assays such as PCR and ELISA exist to detect Nhe, those methods cannot differentiate between active and inactive forms of Nhe. The existing rabbit ileal loop bioassay used to detect Nhe activity is ethically disfavored because it uses live experimental animals. Here we present a custom built low-cost CCD based luminometer and applied it in conjunction with a cell-based assay using Vero cells transduced to express the luciferase enzyme. The activity of Nhe was measured as its ability to inhibit synthesis of luciferase as quantified by reduction of light emission by the luciferase reaction. Emitted light intensity was observed to be inversely proportional to Nhe concentration over a range of 7 ng/ml to 125 ng/ml, with a limit of detection of 7 ng/ml Nhe.


Assuntos
Enterotoxinas/metabolismo , Medições Luminescentes , Animais , Biocatálise , Chlorocebus aethiops , Células HEK293 , Humanos , Luciferases/genética , Luciferases/metabolismo , Células Vero
15.
PLoS One ; 15(9): e0232807, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32986721

RESUMO

Here we have improved an existing mouse model of prostate cancer based on prostate-specific deletion of Pten and Trp53 by incorporating a Cre-activatable luciferase reporter. By coupling the deletion of those genes to the activation of a luciferase reporter, we were able to monitor tumor burden non-invasively over time. We show that, consistent with previous reports, deletion of both Pten and Trp53 on a C57BL/6 background accelerates tumor growth and results in both the loss of androgen receptor expression and castrate resistant tumors as compared with loss of Pten alone. Loss of Trp53 results in the development of sarcomatoid histology and the expression of markers of epithelial-to-mesenchymal transition Zeb1 and vimentin, with kinetics and penetrance dependent on whether one or both alleles of Trp53 were deleted. Homozygous deletion of Trp53 and Pten resulted in uniformly lethal disease by 25 weeks. While we were able to detect locally invasive disease in the peritoneal cavity in aggressive tumors from the double knockout mice, we were unable to detect lymphatic or hematogenous metastatic disease in lymph nodes or at distant sites.


Assuntos
Modelos Animais de Doenças , PTEN Fosfo-Hidrolase/genética , Neoplasias de Próstata Resistentes à Castração/genética , Deleção de Sequência , Proteína Supressora de Tumor p53/genética , Animais , Biomarcadores Tumorais/genética , Carcinogênese , Transição Epitelial-Mesenquimal , Medições Luminescentes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monitorização Fisiológica
16.
J Clin Virol ; 131: 104609, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32866811

RESUMO

INTRODUCTION: IgG immunoassays have been developed and used widely for clinical samples and serosurveys for SARS-CoV2, with most detecting antibodies against the spike/receptor-binding-domain or nucleocapsid. Limited information is available on comparative evaluation of IgG immunoassays against a clinical reference standard, i.e., RT-PCR positivity with >20 days of illness. This study addresses the need for comparing clinical performance of IgG immunoassays with respect to this alternate reference standard. METHODS: We compared the performance of three immunoassays, an in-house RBD assay, and two commercial assays, the Diasorin LIAISON SARS-CoV-2 S1/S1 IgG CLIA which detects antibodies against S1/S2 domains of the Spike protein and the Zydus Kavach assay based on inactivated virus using a well-characterized panel of sera. 379 sera and plasma samples from RTPCR positive individuals >20 days of illness in symptomatic or RT-PCR positivity in asymptomatic individuals and 184 samples collected prior to 2019 were used for assay evaluation. RESULTS: The sensitivity of the assays were 84.7 (95 %CI 80.6-88.1), 82.6 (95 %CI 78.3-86.2) and 75.7 (95 %CI 71.0-79.9) respectively for RBD, LIAISON and Kavach. Kavach and the in-house RBD ELISA showed a specificity of 99.5 % and 100 %, respectively. The RBD and LIAISON (S1/S2) assays showed high agreement (94.7 %; 95 %CI: 92.0, 96.6) and were able to correctly identify more positive sera/plasma than Kavach. CONCLUSION: Independent comparisons support the evaluation of performance characteristics of immunoassays. All three assays are suitable for serosurveillance studies, but in low prevalence sites, estimation of exposure may require adjustment based on our findings.


Assuntos
Anticorpos Antivirais/sangue , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/imunologia , Imunoensaio/métodos , Imunoglobulina G/sangue , Pneumonia Viral/imunologia , Automação Laboratorial , Betacoronavirus , Infecções por Coronavirus/diagnóstico , Humanos , Índia , Estudos Longitudinais , Medições Luminescentes , Pandemias , Estudos Prospectivos , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade
17.
Biosens Bioelectron ; 169: 112572, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32916610

RESUMO

Convalescent serum with a high abundance of neutralization IgG is a promising therapeutic agent for rescuing COVID-19 patients in the critical stage. Knowing the concentration of SARS-CoV-2 S1-specific IgG is crucial in selecting appropriate convalescent serum donors. Here, we present a portable microfluidic ELISA technology for rapid (15 min), quantitative, and sensitive detection of anti-SARS-CoV-2 S1 IgG in human serum with only 8 µL sample volume. We first identified a humanized monoclonal IgG that has a high binding affinity and a relatively high specificity towards SARS-CoV-2 S1 protein, which can subsequently serve as the calibration standard of anti-SARS-CoV-2 S1 IgG in serological analyses. We then measured the abundance of anti-SARS-CoV-2 S1 IgG in 16 convalescent COVID-19 patients. Due to the availability of the calibration standard and the large dynamic range of our assay, we were able to identify "qualified donors" for convalescent serum therapy with only one fixed dilution factor (200 ×). Finally, we demonstrated that our technology can sensitively detect SARS-CoV-2 antigens (S1 and N proteins) with pg/mL level sensitivities in 40 min. Overall, our technology can greatly facilitate rapid, sensitive, and quantitative analysis of COVID-19 related markers for therapeutic, diagnostic, epidemiologic, and prognostic purposes.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Infecções por Coronavirus/virologia , Ensaio de Imunoadsorção Enzimática/instrumentação , Imunoglobulina G/sangue , Técnicas Analíticas Microfluídicas/instrumentação , Pneumonia Viral/virologia , Adolescente , Adulto , Anticorpos Antivirais/imunologia , Antígenos Virais/sangue , Antígenos Virais/imunologia , Técnicas Biossensoriais/economia , Técnicas Biossensoriais/instrumentação , Infecções por Coronavirus/terapia , Ensaio de Imunoadsorção Enzimática/economia , Desenho de Equipamento , Humanos , Imunização Passiva , Imunoglobulina G/imunologia , Limite de Detecção , Medições Luminescentes/economia , Medições Luminescentes/instrumentação , Técnicas Analíticas Microfluídicas/economia , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/terapia , Fatores de Tempo , Adulto Jovem
18.
Sheng Wu Gong Cheng Xue Bao ; 36(8): 1672-1678, 2020 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-32924365

RESUMO

To investigate the detection threshold of Treponema pallidum specific antibody method by chemiluminescent immunoassay (CLIA) in Siemens ADVIA Centaur XP for Syphilis serological test, and compare with the results derived from CMIA, TP-WB and TPPA method. The result can serve as reference for the application of CLIA. In total 30 887 samples screened by Treponema pallidum specific antibody method were collected by Abbott architect i2000 CMIA from July 2018 to July 2019 in Yanda Hospital of Hebei Province. We selected 153 patients with the ratio of sample absorbance to critical value (S/CO) of 1-9 by CMIA screening of Treponema pallidum specific antibody as the research objects. The reverse sequence of syphilis serological detection was adopted, and TP-WB and TPPA were used as the confirmation methods respectively. MedCalc software was used to analyze the results of ROC curve, and the cut-off value was obtained. Chi square test was used to test the difference significance of counting data. The detection results of Treponema pallidum specific antibody in the same batch of serum samples were unequal by different methods. There was no significant difference between CLIA method and TPPA method, but significant difference between CLIA method with TP-WB method and CMIA method was found. TPPA test results and TP-WB test results were taken as gold standards, ROC curve analysis showed that the best diagnostic cutoff value of CLIA method was 4.01 and 16.06, respectively, and the area under the curve was 0.961 and 0.838. The suggested cutoff value of CLIA method is quite different when using different syphilis serological test methods as the gold standard, Therefore, when the S/CO value determined by CLIA is between 1.00 to 16.06, TP-WB method should be recommended as the first choice in laboratory serological test for recheck and confirmation to avoid clinical misdiagnosis.


Assuntos
Anticorpos Antibacterianos , Sorodiagnóstico da Sífilis , Treponema pallidum , Anticorpos Antibacterianos/sangue , Humanos , Medições Luminescentes , Sorodiagnóstico da Sífilis/métodos , Sorodiagnóstico da Sífilis/normas
19.
Nat Commun ; 11(1): 4655, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938918

RESUMO

Purely organic room-temperature phosphorescence has attracted attention for bioimaging but can be quenched in aqueous systems. Here we report a water-soluble ultralong organic room-temperature phosphorescent supramolecular polymer by combining cucurbit[n]uril (CB[7], CB[8]) and hyaluronic acid (HA) as a tumor-targeting ligand conjugated to a 4-(4-bromophenyl)pyridin-1-ium bromide (BrBP) phosphor. The result shows that CB[7] mediated pseudorotaxane polymer CB[7]/HA-BrBP changes from small spherical aggregates to a linear array, whereas complexation with CB[8] results in biaxial pseudorotaxane polymer CB[8]/HA-BrBP which transforms to relatively large aggregates. Owing to the more stable 1:2 inclusion complex between CB[8] and BrBP and the multiple hydrogen bonds, this supramolecular polymer has ultralong purely organic RTP lifetime in water up to 4.33 ms with a quantum yield of 7.58%. Benefiting from the targeting property of HA, this supramolecular polymer is successfully applied for cancer cell targeted phosphorescence imaging of mitochondria.


Assuntos
Mitocôndrias/efeitos dos fármacos , Polímeros/química , Células A549 , Células HEK293 , Humanos , Ácido Hialurônico/química , Ligação de Hidrogênio , Medições Luminescentes , Microscopia Confocal , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Polímeros/metabolismo , Taxoides/química , Temperatura
20.
Medicine (Baltimore) ; 99(38): e22239, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32957368

RESUMO

BACKGROUND: Prolactin (PRL), an inflammatory hormone with cytokine properties, has long been considered to play a crucial role in the pathogenesis of autoimmune diseases, including systemic sclerosis (SSc). However, the plasma/serum levels of PRL in SSc were inconsistent in published studies. The aim of this study was to evaluate the plasma/serum levels of PRL in patients with SSc accurately. METHODS: Electronic databases, including PubMed, EMBASE, Cochrane Library, CNKI, VIP and WANFANG databases, were searched up to October 15, 2019. Pooled standard mean difference (SMD) with 95% confidence interval (CI) was calculated by fixed-effect or random-effects model analysis. All statistical analyses were conducted with STATA 12.0. RESULTS: Fifty three articles were obtained after searching databases, and 9 studies with 293 SSc patients and 282 controls were finally included. The meta-analysis showed that the plasma/serum PRL level in SSC patients was significantly increased compared with the healthy controls, with the SMD of 1.00 and 95% CI (0.56, 1.43). Subgroup analysis showed that female patients had higher plasma/serum PRL levels. However, no significant change in plasma/serum PRL levels was observed in male patients (P = .318). In subgroup analysis by detection type, electrochemiluminescence immunoassay (ECLIA) group and enzyme-linked immunosorbent assay (ELISA) group showed higher PRL levels among SSc patients. CONCLUSIONS: In summary, our meta-analysis showed a significantly higher plasma/serum PRL level in SSc patients than healthy controls, and it was associated with gender and detection method.


Assuntos
Prolactina/metabolismo , Escleroderma Sistêmico/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Medições Luminescentes , Masculino , Fatores Sexuais
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