RESUMEN
Porcine circovirus (PCV) has become a major pathogen, causing major economic losses in the global pig industry, and PCV type 2 (PCV2) and 3 (PCV3) are distributed worldwide. We designed specific primer and probe sequences targeting PCV2 Cap and PCV3 Rap and developed a multiplex crystal digital PCR (cdPCR) method after optimizing the primer concentration, probe concentration, and annealing temperature. The multiplex cdPCR assay permits precise and differential detection of PCV2 and PCV3, with a limit of detection of 1.39 × 101 and 1.27 × 101 copies/reaction, respectively, and no cross-reaction with other porcine viruses was observed. The intra-assay and interassay coefficients of variation (CVs) were less than 8.75%, indicating good repeatability and reproducibility. To evaluate the practical value of this assay, 40 tissue samples and 70 feed samples were tested for both PCV2 and PCV3 by cdPCR and quantitative PCR (qPCR). Using multiplex cdPCR, the rates of PCV2 infection, PCV3 infection, and coinfection were 28.45%, 1.72%, and 12.93%, respectively, and using multiplex qPCR, they were 25.00%, 0.86%, and 4.31%, respectively This highly specific and sensitive multiplex cdPCR thus allows accurate simultaneous detection of PCV2 and PCV3, and it is particularly well suited for applications that require the detection of small amounts of input nucleic acid or samples with intensive processing and complex matrices.
Asunto(s)
Infecciones por Circoviridae , Circovirus , Reacción en Cadena de la Polimerasa Multiplex , Enfermedades de los Porcinos , Circovirus/genética , Circovirus/aislamiento & purificación , Circovirus/clasificación , Porcinos , Animales , Infecciones por Circoviridae/veterinaria , Infecciones por Circoviridae/virología , Infecciones por Circoviridae/diagnóstico , Enfermedades de los Porcinos/virología , Enfermedades de los Porcinos/diagnóstico , Reacción en Cadena de la Polimerasa Multiplex/métodos , Sensibilidad y Especificidad , Reproducibilidad de los Resultados , Cartilla de ADN/genética , ADN Viral/genéticaRESUMEN
The pollution from waste plastic express packages (WPEPs), especially microplastic (MP) fragments, caused by the blowout development of the express delivery industry has attracted widespread attention. On account of the variety of additives, strong complexity, and high diversity of plastic express packages (PEPs), the multi-class classification of WPEPs is a typical large-class-number classification (LCNC). The traceability and identification of microplastic fragments from WPEPs is very challenging. An effective chemometric method for large-class-number classification would be very beneficial for the comprehensive treatment of WPEP pollution through the recycling and reuse of waste plastic express packages, including microplastic fragments and plastic debris. Rather than using the traditional one-against-one (OAO) and one-against-all (OAA) dichotomies, an exhaustive and parallel half-against-half (EPHAH) decomposition, which overcomes the defects of the OAO's classifier learning limitations and the OAA's data proportion imbalance, is proposed for feature selection. EPHAH analysis, combined with partial least squares discriminant analysis (PLS-DA) for large-class-number classification, was performed on 750 microplastic fragments of polyethylene WPEPs from 10 major courier companies using near-infrared (NIR) spectroscopy. After the removal of abnormal samples through robust principal component analysis (RPCA), the root mean square error of cross-validation (RMSECV) value for the model was reduced to 0.01, which was 21.5% lower than that including the abnormal samples. The best models of PLS-DA were obtained using SNV combined with SG-17 smoothing and 2D (SNV+SG-17+2D); the latent variables (LVs), the error rates of Monte Carlo cross-validation (ERMCCVs), and the final classification accuracies were 6.35, 0.155, and 88.67% for OAO-PLSDA; 5.37, 0.103, and 87.33% for OAA-PLSDA; and 3.12, 0.054, and 96.00% for EPHAH-PLSDA. The results showed that the EPHAH strategy can completely learn the complex LCNC decision boundaries for 10 classes, effectively break the tie problem, and greatly improve the voting resolution, thereby demonstrating significant superiority to both the OAO and OAA strategies in terms of classification accuracy. Meanwhile, PLS-DA further maximized the covariance and data interpretation abilities between the potential variables and categories of microplastic debris, thereby establishing an ideal performance identification model with a recognition rate of 96.00%.
RESUMEN
The H5N1 avian influenza virus seriously affects the health of poultry and humans. Once infected, the mortality rate is very high. Therefore, accurate and timely detection of the H5N1 avian influenza virus is beneficial for controlling its spread. This article establishes a dual gene detection method based on dual RPA for simultaneously detecting the HA and M2 genes of H5N1 avian influenza virus, for the detection of H5N1 avian influenza virus. Design specific primers for the conserved regions of the HA and M2 genes. The sensitivity of the dual RT-RPA detection method for HA and M2 genes is 1 × 10-7 ng/µL. The optimal primer ratio is 1:1, the optimal reaction temperature is 40 °C, and the optimal reaction time is 20 min. Dual RT-RPA was used to detect 72 samples, and compared with RT-qPCR detection, the Kappa value was 1 (p value < 0.05), and the clinical sample detection sensitivity and specificity were both 100%. The dual RT-RPA method is used for the first time to simultaneously detect two genes of the H5N1 avian influenza virus. As an accurate and convenient diagnostic tool, it can be used to diagnose the H5N1 avian influenza virus.
Asunto(s)
Subtipo H5N1 del Virus de la Influenza A , Gripe Aviar , Subtipo H5N1 del Virus de la Influenza A/genética , Animales , Gripe Aviar/virología , Gripe Aviar/diagnóstico , Humanos , Sensibilidad y Especificidad , Gripe Humana/virología , Gripe Humana/diagnóstico , Proteínas de la Matriz Viral/genética , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Aves/virología , Proteínas ViroporinasRESUMEN
The recent pandemic of SARS-CoV-2 has underscored the critical need for rapid and precise viral detection technologies. Point-of-care (POC) technologies, which offer immediate and accurate testing at or near the site of patient care, have become a cornerstone of modern medicine. Prokaryotic Argonaute proteins (pAgo), proficient in recognizing target RNA or DNA with complementary sequences, have emerged as potential game-changers. pAgo present several advantages over the currently popular CRISPR/Cas systems-based POC diagnostics, including the absence of a PAM sequence requirement, the use of shorter nucleic acid molecules as guides, and a smaller protein size. This review provides a comprehensive overview of pAgo protein detection platforms and critically assesses their potential in the field of viral POC diagnostics. The objective is to catalyze further research and innovation in pAgo nucleic acid detection and diagnostics, ultimately facilitating the creation of enhanced diagnostic tools for clinic viral infections in POC settings.
Asunto(s)
Ácidos Nucleicos , Sistemas de Atención de Punto , Humanos , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Células Procariotas/metabolismo , Pruebas en el Punto de Atención , Sistemas CRISPR-CasRESUMEN
Avian influenza is caused by avian influenza virus infection; the H5N1 avian influenza virus is a highly pathogenic subtype, affecting poultry and human health. Since the discovery of the highly pathogenic subtype of the H5N1 avian influenza virus, it has caused enormous losses to the poultry farming industry. It was recently found that the H5N1 avian influenza virus tends to spread among mammals. Therefore, early rapid detection methods are highly significant for effectively preventing the spread of H5N1. This paper discusses the detection technologies used in the detection of the H5N1 avian influenza virus, including serological detection technology, immunological detection technology, molecular biology detection technology, genetic detection technology, and biosensors. Comparisons of these detection technologies were analyzed, aiming to provide some recommendations for the detection of the H5N1 avian influenza virus.
Asunto(s)
Subtipo H5N1 del Virus de la Influenza A , Virus de la Influenza A , Gripe Aviar , Animales , Humanos , Gripe Aviar/diagnóstico , Subtipo H5N1 del Virus de la Influenza A/genética , Aves de Corral , Agricultura , MamíferosRESUMEN
This paper presents a method for the protected geographical indication discrimination of Ophiopogon japonicus from Zhejiang and elsewhere using near-infrared (NIR) spectroscopy combined with chemometrics. A total of 3657 Ophiopogon japonicus samples from five major production areas in China were analyzed by NIR spectroscopy, and divided into 2127 from Zhejiang and 1530 from other areas ('non-Zhejiang'). Principal component analysis (PCA) was selected to screen outliers and eliminate them. Monte Carlo cross validation (MCCV) was introduced to divide the training set and test set according to a ratio of 3:7. The raw spectra were preprocessed by nine single and partial combination methods such as the standard normal variable (SNV) and derivative, and then modeled by partial least squares regression (PLSR), a support vector machine (SVM), and soft independent modeling of class analogies (SIMCA). The effects of different pretreatment and chemometrics methods on the model are discussed. The results showed that the three pattern recognition methods were effective in geographical origin tracing, and selecting the appropriate preprocessing method could improve the traceability accuracy. The accuracy of PLSR after the standard normal variable was better, with R2 reaching 0.9979, while that of the second derivative was the lowest with an R2 of 0.9656. After the SNV pretreatment, the accuracy of the training set and test set of SVM reached the highest values, which were 99.73% and 98.40%, respectively. The accuracy of SIMCA pretreated with SNV and MSC was the highest for the origin traceability of Ophiopogon japonicus, which could reach 100%. The distance between the two classification models of SIMCA-SNV and SIMCA-MSC is greater than 3, indicating that the SIMCA model has good performance.
Asunto(s)
Ophiopogon , Espectroscopía Infrarroja Corta , Espectroscopía Infrarroja Corta/métodos , Quimiometría , Geografía , Análisis de los Mínimos Cuadrados , Análisis de Componente PrincipalRESUMEN
Rice cultivation is one of the most significant human-created sources of methane gas. How to accurately measure the methane concentration produced by rice cultivation has become a major problem. The price of the automatic gas sampler used as a national standard for methane detection (HJ 38-2017) is higher than that of gas chromatography, which greatly increases the difficulty of methane detection in the laboratory. This study established a novel methane detection method based on manual injection and split pattern by changing the parameters of the national standard method without adding any additional automatic gas samplers. The standard curve and correlation coefficient obtained from the parallel determination of methane standard gas were y = 2.4192x + 0.1294 and 0.9998, respectively. Relative standard deviation (RSD, <2.82%), recycle rate (99.67−102.02%), limit of detection (LOD, 0.0567 ppm) and limit of quantification (LOQ, 0.189 ppm) of this manual injection method are satisfying, demonstrating that a gas chromatography-flame ionization detector (GC-FID), based on manual injection at a split ratio (SR) of 5:1, could be an effective and accurate method for methane detection. Methane gases produced by three kinds of low-methane rice treated with oxantel pamoate acid, fumaric acid and alcohol, were also collected and detected using the proposed manual injection approach Good peak shapes were obtained, indicating that this approach could also be used for quantification of methane concentration.
Asunto(s)
Metano , Oryza , Cromatografía de Gases/métodos , Ionización de Llama , Gases/análisis , Humanos , Metano/análisisRESUMEN
Cervical cancer is the second most common cancer in the world's woman population with a high incidence in developing countries where diagnostic conditions for the cancer are poor. The main culprit causing the cancer is the human papillomavirus (HPV). HPV is divided into three major groups, i.e., high-risk (HR) group, probable high-risk (pHR) group, and low-risk (LR) group according to their potential of causing cervical cancer. Therefore, developing a sensitive, reliable, and cost-effective point-of-care diagnostic method for the virus genotypes in developing countries even worldwide is of high importance for the cancer prevention and control strategies. Here we present a combined method of isothermal recombinase polymerase amplification (RPA), lateral flow dipstick (LFD), and reverse dot blot (RDB), in quick point-of-care identification of HPV genotypes. The combined method is highly specific to HPV when the conserved L1 genes are used as targeted genes for amplification. The method can be used in identification of HPV genotypes at point-of-care within 1 h with a sensitivity of low to 100 fg of the virus genomic DNA. We have demonstrated that it is an excellent diagnostic point-of-care assay in monitoring the disease without time-consuming and expensive procedures and devices.
Asunto(s)
Southern Blotting/métodos , Genes Virales , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/diagnóstico , Sistemas de Atención de Punto , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Secuencia de Aminoácidos , ADN Viral/análisis , ADN Viral/normas , Humanos , Límite de Detección , Papillomaviridae/genética , Infecciones por Papillomavirus/virología , Reproducibilidad de los ResultadosRESUMEN
Rab26 GTPase modulates the trafficking of cell surface receptors, such as G protein-coupled receptors including α2-adrenergic receptors in some cell types. However, the effect of Rab26 on ß2-adrenergic receptor (ß2-AR) trafficking or/and Toll-like receptor 4 (TLR4) expression in human pulmonary microvascular endothelial cells (HPMECs) is still unclear. Here, we investigated the role of Rab26 in regulating the expression of ß2-ARs and TLR4 in HPMECs and the effect of these receptors' imbalance on endothelial cell barrier function. The results showed that there was unbalance expression in these receptors, where ß2-AR expression was remarkably reduced, and TLR4 was increased on the cell membrane after lipopolysaccharide (LPS) treatment. Furthermore, we found that Rab26 overexpression not only upregulated ß2-ARs but also downregulated TLR4 expression on the cell membrane. Subsequently, the TLR4-related inflammatory response was greatly attenuated, and the hyperpermeability of HPMECs also was partially relived. Taken together, these data suggest that basal Rab26 maintains the balance between ß2-ARs and TLR4 on the cell surface, and it might be a potential therapeutic target for diseases involving endothelial barrier dysfunction.
Asunto(s)
Células Endoteliales/metabolismo , Inflamación/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Receptor Toll-Like 4/metabolismo , Proteínas de Unión al GTP rab/metabolismo , Citometría de Flujo , Humanos , Inflamación/inmunología , Microscopía Confocal , Microvasos/citología , Microvasos/metabolismo , ARN Interferente Pequeño/metabolismo , Transducción de Señal , Proteínas de Unión al GTP rab/inmunologíaRESUMEN
Purpose: To investigate the efficacy of α-adrenergic agonist brimonidine either alone or combined with pirenzepine for inhibiting progressing myopia in guinea pig lens-myopia-induced models. Methods: Thirty-six guinea pigs were randomly divided into six groups: Group A received 2% pirenzepine, Group B received 0.2% brimonidine, Group C received 0.1% brimonidine, Group D received 2% pirenzepine + 0.2% brimonidine, Group E received 2% pirenzepine + 0.1% brimonidine, and Group F received the medium. Myopia was induced in the right eyes of all guinea pigs using polymethyl methacrylate (PMMA) lenses for 3 weeks. Eye drops were administered accordingly. Intraocular pressure was measured every day. Refractive error and axial length measurements were performed once a week. The enucleated eyeballs were removed for hematoxylin and eosin (H&E) and Van Gieson (VG) staining at the end of the study. Results: The lens-induced myopia model was established after 3 weeks. Treatment with 0.1% brimonidine alone and 0.2% brimonidine alone was capable of inhibiting progressing myopia, as shown by the better refractive error (p=0.024; p=0.006) and shorter axial length (p=0.005; p=0.0017). Treatment with 0.1% brimonidine and 0.2% brimonidine combined with 2% pirenzepine was also effective in suppressing progressing refractive error (p=0.016; p=0.0006) and axial length (p=0.017; p=0.0004). The thickness of the sclera was kept stable in all groups except group F; the sclera was much thinner in the lens-induced myopia eyes compared to the control eyes. Conclusions: Treatment with 0.1% brimonidine alone and 0.2% brimonidine alone, as well as combined with 2% pirenzepine, was effective in inhibiting progressing myopia. The result indicates that intraocular pressure elevation is possibly a promising mechanism and potential treatment for progressing myopia.
Asunto(s)
Agonistas de Receptores Adrenérgicos alfa 2/uso terapéutico , Tartrato de Brimonidina/uso terapéutico , Modelos Animales de Enfermedad , Miopía/tratamiento farmacológico , Animales , Quimioterapia Combinada , Cobayas , Presión Intraocular/fisiología , Antagonistas Muscarínicos/uso terapéutico , Miopía/fisiopatología , Soluciones Oftálmicas , Proyectos Piloto , Pirenzepina/uso terapéutico , Errores de Refracción/fisiopatologíaRESUMEN
BACKGROUND: Human papillomavirus (HPV) infection is linked to cervical cancer. With the technological development of molecular biology and epidemiology, detection and treatment of HPV has become an important mean to prevent cervical cancer. METHODS: A simple, rapid, and sensitive colorimetric loop-mediated isothermal amplification (LAMP) method was established herein to detect 23 HPV genotypes. The sequences of the primers for the LAMP reaction were located in the L1 gene of the HPV genome. As it is a fluorescent dye, calcein was added before the reaction. The reaction was run under isothermal conditions at 65°C for 40 minutes. A positive reaction was indicated by a color change from yellow to fluorescent green. The fluorescence curve diagram represents the monitoring of real time quantitative instrument. 450 cervical swab samples from patients with single infections of 23 different HPV genotypes were examined to evaluate the specificity. RESULTS: The results revealed no cross-reaction with other HPV genotypes. A serial dilution of a cloned plasmid containing 23 HPV L1 gene sequences was employed to evaluate the sensitivity. Different HPV subtypes have different detection capability. The sensitivity of different HPV subtypes tested by LAMP assay was in the range from 1.0 x10 to 4.0 x 103 copies per reaction. The LAMP assay and the RDB (reverse dot blot) were compared for detecting and genotyping HPV among the 450 clinical samples. There were 385 (85.6%) and 375 (83.3%) HPV positive specimens detected by LAMP and RDB, respectively, as well as 306 (68.0%) and 296 (65.8%) for HR-HPV positive specimens. The agreement between the LAMP and RDB assays was 93.3% (κ = 0.75) for HPV positivity and 94.7% (κ = 0.88) for HR-HPV positivity. CONCLUSIONS: It was concluded that this colorimetric LAMP assay had potential application for the rapid screening of the HPV infection in resource-limited hospitals or rural clinics.
Asunto(s)
Papillomaviridae/genética , Colorimetría , Cartilla de ADN , Genotipo , Humanos , Técnicas de Amplificación de Ácido Nucleico , Infecciones por PapillomavirusRESUMEN
BACKGROUND: Cervical cancer is a common gynecologic malignant tumor and has a great impact on women's health. Human papillomavirus (HPV) is implicated in cervical cancer and precancerous lesions and the two are possibly two stages of disease progression. With the technological development of molecular biology and epidemiology, detection and treatment of HPV has become an important means to prevent cervical cancer. METHODS: Here we present a novel, rapid, sensitive and specific isothermal method of recombinase polymerase amplification (RPA), which is established to detect the two most common high-risk human papillomavirus type 16 and type 18 DNA. In this study, we evaluate the efficacy of the RPA assay, incubating clinical specimens of HPV16 and HPV18 using plasmids standard. It operates at constant low temperature without the thermal instrumentation for incubation. The products can be detected via agarose gel electrophoresis assay, reverse dot blot assay, and quantitative real-time assay with SYBR Green I. We assess the diagnostic performance of the RPA assay for detecting of HPV16 and HPV18 in 335 clinical samples from patients suspected of cervical cancer. RESULTS: The results revealed no cross-reaction with other HPV genotypes and the RPA assay achieve a sensitivity of 100 copies. Compared with TaqMan qPCR, the RPA technique achieves exponential amplification with no need for pretreatment of sample DNA at 37°C for 20 minutes, which reveals more satisfactory performance. The agreement between the RPA and qPCR assays was 97.6% (κ = 0.89) for HPV16 positivity and 98.5% (κ = 0.81) for HPV18 positivity, indicating very good correlation between both tests. CONCLUSIONS: Importantly, the RPA assay was demonstrated to be a useful and powerful method for detection of HPV virus, which therefore may serve as a valuable tool for rapid diagnosis of HPV infection in both commercial and clinical applications.
Asunto(s)
ADN Viral/genética , Pruebas de ADN del Papillomavirus Humano/métodos , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Infecciones por Papillomavirus/diagnóstico , Reacción en Cadena de la Polimerasa/métodos , Recombinasas/metabolismo , Neoplasias del Cuello Uterino/diagnóstico , Adolescente , Adulto , Calibración , Femenino , Genotipo , Pruebas de ADN del Papillomavirus Humano/normas , Humanos , Persona de Mediana Edad , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/virología , Reacción en Cadena de la Polimerasa/normas , Valor Predictivo de las Pruebas , Reacción en Cadena en Tiempo Real de la Polimerasa , Estándares de Referencia , Reproducibilidad de los Resultados , Temperatura , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/virología , Flujo de Trabajo , Adulto JovenRESUMEN
NAT2 plays a critical role in external chemical detoxification. Thus, polymorphism of NAT2 has been suggested to associate with several disorders. A number of studies have been devoted to the relationship between NAT2 polymorphism and asthma risk. However, the results were inconclusive. In this study we aimed to derive a more precise estimation of the association. A literature search in the common databases was conducted and then meta-analyses evaluating the association of NAT2 polymorphism and asthma risk were performed. Eligible studies were identified for the period up to May 2013. A total of five case-control studies containing 946 cases and 1,091 controls were lastly included for analysis. The overall data showed that slow acetylators of NAT2 might have an association with increased asthma risk (OR 2.20; 95% CI 1.31-3.72). The pooled data suggest that slow acetylators of NAT2 might contribute to asthma risk among Caucasians. Future studies are needed to confirm this conclusion.
Asunto(s)
Arilamina N-Acetiltransferasa/genética , Asma/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Acetilación , Asma/epidemiología , Asma/patología , Estudios de Casos y Controles , Genotipo , Humanos , Factores de Riesgo , Fumar/genética , Población Blanca/genéticaRESUMEN
Olaquindox (OLA) and quinocetone (QCT) have been prohibited in aquatic products due to their significant toxicity and side effects. In this study, rapid and visual europium nanoparticle (EuNP)-based lateral flow strip biosensors (LFSBs) were developed for the simultaneous quantitative detection of OLA, QCT, and 3-methyl-quinoxaline-2-carboxylic acid (MQCA) in fish feed and tissue. The EuNP-LFSBs enabled sensitive detection for OLA, QCT, and MQCA with a limit of detection of 0.067, 0.017, and 0.099 ng/mL (R2 ≥ 0.9776) within 10 min. The average recovery of the EuNP-LFSBs was 95.13%, and relative standard deviations were below 9.38%. The method was verified by high-performance liquid chromatography (HPLC), and the test results were consistent. Therefore, the proposed LFSBs serve as a powerful tool to monitor quinoxalines in fish feeds and their residues in fish tissues.
Asunto(s)
Alimentación Animal , Antibacterianos , Técnicas Biosensibles , Europio , Peces , Quinoxalinas , Quinoxalinas/análisis , Animales , Antibacterianos/análisis , Alimentación Animal/análisis , Nanopartículas , Cromatografía Líquida de Alta Presión , Nanopartículas del MetalRESUMEN
Nitrofuran (NF) antibiotics have been banned worldwide in aquaculture due to their potential carcinogenicity and mutagenicity. Because of the short half-life of NF antibiotics, an easy and sensitive multiple lateral flow immunoassay (mLFIA) based on europium nanoparticles (EuNPs) has been successfully established to simultaneously and quantitatively detect 3-amino-5-morpholinomethyl-2-oxazolidinone (AMOZ), 3-amino-2-oxazolidinone (AOZ) and sodium nifurstylenate (NFS) in aquatic products. The EuNP-mLFIA assay was accomplished within 10 min. The limits of detection (LODs) for AOZ, AMOZ and NFS were 0.013, 0.019 and 0.023 ng/mL, respectively. The average recoveries of AOZ, AMOZ and NFS were 98.0-104.4%, 96.0-102.6% and 98.0-102.8%, respectively. It showed satisfactory consistency, and the feasibility was validated by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Briefly, this method will become a powerful tool for monitoring multiple NF antibiotics and provide promising applications in the field of food safety and environmental testing.
Asunto(s)
Nanopartículas del Metal , Nitrofuranos , Antibacterianos/análisis , Europio , Espectrometría de Masas en Tándem/métodos , Nitrofuranos/análisis , InmunoensayoRESUMEN
Small molecules are significant risk factors for causing food safety issues, posing serious threats to human health. Sensitive screening for hazards is beneficial for enhancing public security. However, traditional detection methods are unable to meet the requirements for the field screening of small molecules. Therefore, it is necessary to develop applicable methods with high levels of sensitivity and specificity to identify the small molecules. Aptamers are short-chain nucleic acids that can specifically bind to small molecules. By utilizing aptamers to enhance the performance of recognition technology, it is possible to achieve high selectivity and sensitivity levels when detecting small molecules. There have been several varieties of aptamer target recognition techniques developed to improve the ability to detect small molecules in recent years. This review focuses on the principles of detection platforms, classifies the conjugating methods between small molecules and aptamers, summarizes advancements in aptamer-based conjugate recognition techniques for the detection of small molecules in food, and seeks to provide emerging powerful tools in the field of point-of-care diagnostics.
RESUMEN
Adding an appropriate amount of copper to feed can promote the growth and development of livestock; however, a large amount of heavy metal copper can accumulate in livestock through the enrichment effect, which poses a serious threat to human health. Traditional Cu2+ detection relies heavily on complex and expensive instruments, such as inductively coupled plasma-optical emission spectrometry (ICP-OES) and inductively coupled plasma-mass spectrometry (ICP-MS); thus, convenient and simple rapid detection technologies are urgently needed. In this paper, synthesized copper antigens were used to immunize mice and highly specific anticopper monoclonal antibodies were obtained, which were verified to exhibit high affinity and specificity. Based on the above antibodies, an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) was established for the rapid detection of copper content in pork. The standard inhibition curve of the method was obtained by antigen-antibody working concentration screening, in which the half inhibitory concentration (IC50) was 11.888 ng/mL, the limit of detection (LOD) was 0.841 ng/mL and the correlation coefficient R2 of the curve was 0.998. In the additive recovery experiment, the recovery rate ranged from 90% to 110%, and the coefficient of variation (CV) was less than 10%, indicating that the method achieved high accuracy and precision. Finally, the results of ic-ELISA combined with Bland-Altman analysis showed a high correlation with ICP-MS, and the correlation coefficient (R2) reached 0.990 when the copper concentration was less than 200 ng/mL. Thus, the ic-ELISA method exhibits high reliability.
Asunto(s)
Cobre , Ensayo de Inmunoadsorción Enzimática , Productos de la Carne , Ensayo de Inmunoadsorción Enzimática/métodos , Animales , Productos de la Carne/análisis , Ratones , Contaminación de Alimentos/análisis , Humanos , PorcinosRESUMEN
INTRODUCTION: The purpose of this study is to summarize the benefits of the double-deck viscoelastic technique (DDVT), a novel and cost-effective surgical technique that creates a barrier to hinder silicone oil (SO) from connecting and damaging the corneal endothelium in aphakic and SO-dependent eyes. METHODS: Five SO-dependent and aphakic eyes underwent double-deck viscoelastic embedment and penetrating keratoplasty (PKP) in this retrospective case series. At 1, 6, 12, 18, and 24 months after surgery, clinical outcomes including best corrected visual acuity (BCVA), intraocular pressure (IOP), corneal endothelial cell density (ECD), and double-deck viscoelastic layer imaging were evaluated. A Heidelberg Retina Tomograph confocal microscope was used to measure ECD. Ultrasound biomicroscopy (UBM) was used to image the double-deck viscoelastic layer. RESULTS: Postoperatively, the BCVA of the patients ranged from hand motion detection to 20/200, and their IOP was between 7 and 10 mmHg. The two-deck viscoelastic layer remained mostly static. Patients showed varying degrees of ECD reduction, with ECD loss rates in the first 6 months ranging from 6.7 to 75.8 cells/mm2/month and then declining to 2.2-14.3 cells/mm2/month. CONCLUSION: In SO-dependent aphakic eyes, double-deck viscoelastic embedment could effectively inhibit SO-corneal endothelium interaction. This technique could lower the pace of ECD loss and lengthen the time of corneal transparency, giving aphakic and silicone oil-dependent patients the opportunity to accept PKP surgery and get better vision quality.
RESUMEN
BACKGROUND: Viral pleurisy is a viral infected disease with exudative pleural effusions. It is one of the causes for pleural effusions. Because of the difficult etiology diagnosis, clinically pleural effusions tend to be misdiagnosed as tuberculous pleurisy or idiopathic pleural effusion. Here, we report a case of pleural effusion secondary to viral pleurisy which is driven by infection with epstein-barr virus. Viral infection was identified by metagenomic next-generation sequencing (mNGS). CASE SUMMARY: A 40-year-old male with a history of dermatomyositis, rheumatoid arthritis, and secondary interstitial pneumonia was administered with long-term oral prednisone. He presented with fever and chest pain after exposure to cold, accompanied by generalized sore and weakness, night sweat, occasional cough, and few sputums. The computed tomography scan showed bilateral pleural effusions and atelectasis of the partial right lower lobe was revealed. The pleural fluids were found to be yellow and slightly turbid after pleural catheterization. Thoracoscopy showed fibrous adhesion and auto-pleurodesis. Combining the results in pleural fluid analysis and mNGS, the patient was diagnosed as viral pleuritis. After receiving Aciclovir, the symptoms and signs of the patient were relieved. CONCLUSION: Viral infection should be considered in cases of idiopathic pleural effusion unexplained by routine examination. mNGS is helpful for diagnosis.
RESUMEN
Drug abuse is becoming increasingly dangerous nowadays. Morphine (MOP), methamphetamine (MET) and ketamine (KET) are the most commonly abused drugs. The abuse of these drugs without supervision can cause serious harm to the human body and also endanger public safety. Developing a rapid and accurate method to screen drug suspects and thus control these drugs is essential to public safety. This paper presents a method for the simultaneous quantitative detection of these three drugs in hair by a europium nanoparticles-based fluorescence immunochromatographic assay (EuNPs-FIA). In our study, the test area of the nitrocellulose membrane was composed of three equally spaced detection lines and a quality control line. The test strip realized the quantitative analysis of the samples by detecting the fluorescence brightness of the europium nanoparticles captured on the test line within 15 min. For the triple test strip, the limits of detection of MOP, KET and MET were 0.219, 0.079 and 0.329 ng/mL, respectively. At the same time, it also showed strong specificity. The strip was stable and could be stored at room temperature for up to one year, and the average recovery rate was 85.98-115.92%. In addition, the EuNPs-FIA was validated by high-performance liquid chromatography (HPLC) analysis, and a satisfactory consistency was obtained. Compared to the current immunochromatographic methods used for detecting abused drugs in hair, this method not only increased the number of detection targets, but also ensured sensitivity, improving detection efficiency to a certain extent. The approach can also be used as an alternative to chromatography. It provides a rapid and accurate screening method for the detection of abused drugs in hair and has great application prospects in regard to public safety.