Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
1.
Sensors (Basel) ; 24(20)2024 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-39460053

RESUMO

Abandoned object detection is a critical task in the field of public safety. However, existing methods perform poorly when detecting small and occluded objects, leading to high false detection and missed detection rates. To address this issue, this paper proposes an abandoned object detection method that integrates an adaptive dual-background model with SAO-YOLO (Small Abandoned Object YOLO). The goal is to reduce false and missed detection rates for small and occluded objects, thereby improving overall detection accuracy. First, the paper introduces an adaptive dual-background model that adjusts according to scene changes, reducing noise interference in the background model. When combined with an improved PFSM (Pixel-based Finite State Machine) model, this enhances detection accuracy and robustness. Next, a network model called SAO-YOLO is designed. Key improvements within this model include the SAO-FPN (Small Abandoned Object FPN) feature extraction network, which fully extracts features of small objects, and a lightweight decoupled head, SODHead (Small Object Detection Head), which precisely extracts local features and enhances detection accuracy through multi-scale feature fusion. Finally, experimental results show that SAO-YOLO increases mAP@0.5 and mAP@0.5:0.95 by 9.0% and 5.1%, respectively, over the baseline model. It outperforms other advanced detection models. Ultimately, after a series of experiments on the ABODA, PETS2006, and AVSS2007 datasets, the proposed method achieved an average detection precious of 91.1%, surpassing other advanced methods. It significantly outperforms other advanced detection methods. This approach notably reduces false and missed detections, especially for small and occluded objects.

2.
Anal Chem ; 94(3): 1585-1593, 2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35021619

RESUMO

Multiplex lateral flow immunoassay (mLFIA) has attracted great attention due to the increasing need for rapid detection of multiple analytes. However, it has a number of disadvantages with regard to accuracy and interference because of difficulties in simplifying the process of preparing nanomaterial-based probes. In this work, inspired by protein self-assembly, for the first time, a facile natural antibody network (NAN)-based mLFIA for multiple chloramphenicol (CAP) and streptomycin (STR) determination was designed. The NAN structure was constructed by introducing a second antibody (Ab2) as a scaffold to noncovalently combine with various monoclonal antibodies (mAbs), thus permitting each mAb to act as an independent functional unit to maintain bioactivity. Furthermore, the NAN was colored by simple one-step staining using coomassie brilliant blue R-250 (CBBR) to form a chromogenic probe, eliminating the need for complex nanomaterials to improve reproducibility and precision. Under optimal conditions, a satisfactory detection performance (the visual limit of detection (v-LOD) of 3 ng mL-1 for CAP and 20 ng mL-1 for STR) was obtained for whole milk analysis, which met the basic requirement of detection and had good specificity, reproducibility (relative standard deviation (RSD) < 15%), and robustness. In addition, the precision of the detection results was improved usefully since the test procedure was simplified. Overall, the developed system enables fast, simple, and reliable point-of-care assays of multiple analytes.


Assuntos
Leite , Testes Imediatos , Animais , Imunoensaio/métodos , Limite de Detecção , Leite/química , Reprodutibilidade dos Testes
3.
Bioresour Technol ; 413: 131443, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39241813

RESUMO

To develop a reliable sulfide (S2-) autotrophic denitrification (SAD) process under S2- and SO42- salinity stresses, the biofilm performance and microbial mechanisms were comparatively studied using different inocula of activated sludge (AS) and intertidal sediment (IS). Biofilm IS enriched more denitrification genes (0.34 %) and S2- oxidation genes (0.29 %) than those with AS. Higher denitrification performance was obtained under S2- (100 mg/L) and SO42- (5-15 g/L Na2SO4) stresses, but no significantly differences were observed under levels of 0-200 mg/L S2- and 30 g/L Na2SO4. Notably, biofilm samples in SAD systems with IS still had more S2- oxidation genes at high S2- levels of 100-200 mg/L and Na2SO4 level of 30 g/L. The key functional genus Thiobacillus accumulated well at 30 g/L Na2SO4, but was strongly inhibited at 200 mg/L S2-. The findings were advantage to SAD application under sulfide and salinity stresses.


Assuntos
Processos Autotróficos , Biofilmes , Desnitrificação , Sulfatos , Sulfetos , Sulfetos/metabolismo , Sulfatos/metabolismo , Sulfatos/farmacologia , Thiobacillus/metabolismo , Esgotos/microbiologia , Estresse Fisiológico , Salinidade , Oxirredução , Sedimentos Geológicos/microbiologia
4.
Biosens Bioelectron ; 230: 115264, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37004282

RESUMO

In this work, we constructed a moderate and convenient approach for the determination of staphylococcus aureus (S. aureus) by using organic-inorganic flower-like hybrid nanoflowers and Pig IgG together in an enzyme-linked immunosorbent assay (ELISA) system. To ensure efficient capture, the hybrid nanoflowers were prepared by encapsulating horseradish peroxidase (HRP) and vancomycin (VAN) in the inorganic nanocrystal composites (calcium ion solution), just like the mimic biomineralization process. Owing to the self-assembly technique, the synthesized VAN-HRP-CaHPO4 nanoflowers (NFs) can not only retain the ability to particularly capture the gram-positive bacteria but also enhance the stability and enzymatic activity to achieve the signal output amplification. Then, taking advantage of the integration of signal amplification elements (HRP) and biorecognition unit (VAN), the VAN-HRP-CaHPO4 NFs were utilized as a new kind of capture & signal regent in the procedure of S. aureus detection. Based on this ELISA system, S. aureus could be clearly detected within the concentration ranging from 1.0 × 102 to 1.0 × 107 CFU mL-1. The detection limit was defined as 4.3 CFU mL-1, which performance is superior to some commercial ELISA kits. Additionally, this system detected the S. aureus in food samples and showed an acceptable recovery. As a cost-effective and sensitive platform, this proposed assay was enable to fulfill the requirement of a quick and effective detection of S. aureus.


Assuntos
Técnicas Biossensoriais , Infecções Estafilocócicas , Animais , Suínos , Antibacterianos , Staphylococcus aureus/química , Técnicas Biossensoriais/métodos , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/microbiologia , Vancomicina/química , Imunoensaio , Limite de Detecção , Peroxidase do Rábano Silvestre/química
5.
Food Chem ; 401: 134133, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36113217

RESUMO

Improving detection sensitivity is still a major research emphasis for lateral flow immunoassay (LFIA). Increasing the binding efficiency and stability of the probe is an achievable and effective solution. In this work, we developed a highly sensitive lateral flow immunoassay for clenbuterol detection by using bismuth sulfide nanoparticle (Bi2S3) nanoparticles (NPs) as a novel marker. Here, Bi2S3 NPs can link with the antibody by hydrogen bonding to improve the performance of the probe, e.g., stability and sensitivity. Benefiting from the direct hydrogen bonding between Bi2S3 NPs and the monoclonal antibody (mAb), high sensitivity is obtained by the proposed LFIA with a lower visible detection limit of 0.1 ng mL-1 and a cut-off value of 4 ng·mL-1 for CLE detection, which is 5-fold and 7.5-fold improved than the conventional Au NPs based LFIA. In addition, the encouraging practical application results in milk, pork, and beef show that the bismuth sulfide nanoparticle has a great popularizing potential in the performance promotion of LFIAs for food safety monitoring.


Assuntos
Clembuterol , Nanopartículas Metálicas , Nanopartículas , Animais , Bovinos , Ouro/química , Ligação de Hidrogênio , Limite de Detecção , Virtudes , Imunoensaio/métodos , Nanopartículas/química , Anticorpos Monoclonais , Nanopartículas Metálicas/química
6.
Food Chem ; 400: 134012, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36055143

RESUMO

Exploring a novel strategy for strengthening the catalytic activity of enzyme facilitates the development of a sensitive enzyme-linked immunosorbent assay (ELISA). Herein, a chemical staining (CS) strategy was firstly discovered to possess the ability to directly improve the catalytic activity of horseradish peroxidase. Based on this discovery, coomassie brilliant blue was introduced into ELISA to establish a CS enhanced ELISA (CS-ELISA) to detect clenbuterol (CL) by simply staining monoclonal antibodies. Satisfactorily, the most important analytical parameters of CS-ELISA, including sensitivity (0.074 ng mL-1) and linear range (0.2-2 ng mL-1) were all improving 2-folds compared with conventional ELISA. Moreover, the CS-ELISA shows good applicability in the detection of CL in pork tenderloin samples. The proposed CS-ELISA shows various advantages, such as cost-effective, easily accessible, enhanced catalytic activity of enzyme, higher sensitivity, and broader linear range, providing a new insight into enhanced ELISA for food safety.


Assuntos
Clembuterol , Anticorpos Monoclonais , Clembuterol/análise , Ensaio de Imunoadsorção Enzimática , Peroxidase do Rábano Silvestre , Coloração e Rotulagem
7.
Front Cardiovasc Med ; 9: 952657, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35966568

RESUMO

Background: Wenxin Keli (WXKL) has good clinical value in the treatment of premature ventricular contractions, but there is insufficient evidence to support it. This study evaluates the efficacy and safety of WXKL combined with metoprolol tartrate in the treatment of ventricular premature beats (VPCs). Methods: We searched seven databases to identify randomized controlled trials (RCTs) for this study. Two reviewers independently screened and extracted the data. The Cochrane Manual criteria were used for methodological quality assessment. Meta-analyses were performed using Review Manager 5.4.1 software. Risk ratios (RR) were used for effect sizes for dichotomous data, demonstrated in effect sizes and 95% confidence intervals (CIs). Results: A total of 11 RCTs of WXKL combined with metoprolol tartrate in the treatment of premature ventricular contractions were included in this study. Meta-analysis showed that WXKL combined with metoprolol tartrate (treatment group) was more effective than metoprolol tartrate (control group) in improving premature ventricular contractions (RR = 1.32, 95% CI: [1.24, 1.40], P < 0.00001); significantly improved the rate of premature ventricular contractions (RR = 1.32, 95% CI: [1.23, 1.41], P < 0.00001); there was no difference in adverse drug reactions compared with the control group (RR = 0.61, 95% CI: [0.35, 0.1.05], P = 0.08), but the number of adverse reactions (n = 18) was less than that of the control group (n = 32), and the severity was lower than that of the control group. The included studies only mentioned randomization and did not describe the generation of random sequences in detail. Conclusion: This study found that Wenxin Keli combined with metoprolol tartrate in the treatment of premature ventricular contractions increased the efficacy of the drug, reduced the occurrence of adverse reactions, and reduced the severity of adverse reactions. Due to the quality limitations of the included studies, more high-quality RCTs are needed in the future to provide more evidence for longer-term analyses.

8.
Biomed Pharmacother ; 149: 112866, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35367767

RESUMO

Parkinson's disease (PD) presents a common challenge for people all over the world and has become a major research hotspot due to the large population affected by the illness and the difficulty of clinical treatment. The prevalence of PD is increasing every year, the pathogenesis is complex, and the current treatment is ineffective. Therefore, it has become imperative to find effective drugs for PD. With the advantages of low cost, high safety and high biological activity, Chinese medicine has great advantages in the prevention and treatment of PD. This review systematically summarizes the potential of Chinese medicine for the treatment of PD, showing that Chinese medicine can exert anti-PD effects through various pathways, such as anti-inflammatory and antioxidant pathways, reducing mitochondrial dysfunction, inhibiting endoplasmic reticulum stress and iron death, and regulating intestinal flora. These mainly involve HMGB1/TLR4, PI3K/Akt, NLRP3/ caspase-1/IL-1ß, Nrf2/HO-1, SIRT1/Akt1, PINK1/parkin, Bcl-2/Bax, BDNF-TrkB and other signaling pathways. In sum, based on modern phytochemistry, pharmacology and genomic proteomics, Chinese medicine is likely to be a potential candidate for PD treatment, which requires more clinical trials to further elucidate its importance in the treatment of PD.


Assuntos
Doença de Parkinson , Antioxidantes/farmacologia , Humanos , Medicina Tradicional Chinesa , Doença de Parkinson/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais
9.
Food Chem ; 377: 131920, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-34979402

RESUMO

Here, a third-stage amplifier indirect probe (TsAIP) based lateral flow immunoassay (LFIA) was proposed to detect furazolidone (FZD) with Prussian blue nanoparticles (PBNPs) as carrier to label the goat anti-mouse antibody-horseradish peroxidase conjugation [GAMA(HRP)]. In this strategy, owing to the fact that one monoclonal antibody (mAb) can combine several GAMA molecules simultaneously, the indirect probe can generate primary signal amplification, then realize second-stage amplification attributing to PBNPs, and finally achieve third-stage amplification because of the conjugated HRP. The TsAIP-based LFIA shows improved performance for FZD metabolite derivative with a detection limit of 1 ng mL-1. The detection range is expanded about 2-fold compared with the original outcome. Besides, the proposed sensor could be successfully applied in food samples. This method provides a platform for broadening the detection range and application of PBNPs based LFIAs.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Animais , Furazolidona , Ouro , Imunoensaio , Limite de Detecção , Camundongos
10.
Food Chem ; 393: 133351, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35689929

RESUMO

Antibiotic abuse has caused serious health risks for human beings for long. To address the problem, novel and facile detection techniques are highly desired. Here, an effective multiplex immunochromatographic platform (MICP) with synthesis-free and cost-effective merits is established for simultaneous detection of antibiotics on a single immunochromatographic assay (ICA) strip. Adopting crystal violet (CV) as a signal tag for multiplex ICA allows for direct coupling with multiple antibodies in several minutes. By combining CV and ICA perfectly, this convenient strategy offers improvements in convenience, speed, flexibility, and portability, eventually ensuring the optimized effectiveness of this approach. As a result, the established platform is successfully used to detect streptomycin (STR) and chloramphenicol (CAP) with visual detection mode, and the obtained total recoveries of milk and honey real samples changed from 83.82 to 113.38% with total RSD values of 0.48 to 4.15%.


Assuntos
Cloranfenicol , Estreptomicina , Antibacterianos/análise , Cloranfenicol/análise , Cromatografia de Afinidade/métodos , Contaminação de Alimentos/análise , Violeta Genciana , Humanos , Limite de Detecção
11.
Adv Mater ; 33(52): e2104355, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34658077

RESUMO

Intracellular delivery of proteins is receiving considerable attention in biotherapeutics for various diseases by replacing dysfunctional proteins. Successful intracellular protein delivery highly relies on the development of efficient and safe polymeric carriers, which remains a grand challenge due to the lack of strong binding sites on proteins and their distinct molecular sizes and polarities. In this work, a strategy is proposed for efficient intracellular protein delivery by using dynamic polymer supra-amphiphiles, which are prepared by grafting boronated polylysine with a series of lipidated catechols via dynamic covalent catechol-boronate ester bonds. The prepared supra-amphiphiles can coassemble with proteins to form stable nanoparticles in water and also enable the release of bound proteins in cells due to their dynamic features, thereby strongly promoting the intracellular delivery process. The lead supra-amphiphiles screened in the library demonstrate high efficiency in the delivery of various proteins including bovine serum albumin, ß-galactosidase, α-chymotrypsin, saporin, R-phycoerythrin, ovalbumin, catalase, and superoxide dismutase, and show great potency in delivering superoxide dismutase to treat ulcerative colitis in vivo. This work provides new opportunities for rational design and facile construction of robust intracellular protein delivery materials by the integration of polymer chemistry and supramolecular engineering strategies.


Assuntos
Polímeros
12.
Food Chem ; 352: 129415, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33711728

RESUMO

Furazolidone (FZD) and its metabolite called 3-amino-2-oxazolidinone (AOZ) would induce carcinogenic and mutagenic effects to human. In this work, to develop a novel, stable, and simple point of care testing (POCT) with a potential to social applied for FZD detection, we utilized the aspect of protein staining of coomassie brilliant blue (CBB) to exploit a new CBB-LFIA strategy free of NPs. Only one mixing step is needed during the probe manufacturing process, which requires just 2 h and is a great time saving strategy compared with other methods (requiring 4-33 h for probe preparation). Besides, the cost of CBB-LFIA is 300 times lesser than other LFIA with respect to obtaining the label. The developed CBB-LFIA was successfully applied to detect AOZ with a detection limit of 2 ng mL-1, without any influence from other potential interfering compounds. The proposed CBB-LFIA exhibited prominent practical application, and possesses considerable utilization potential in the related field.


Assuntos
Custos e Análise de Custo , Furazolidona/análise , Furazolidona/química , Imunoensaio/economia , Imunoensaio/métodos , Sistemas Automatizados de Assistência Junto ao Leito/economia , Corantes de Rosanilina/química , Humanos , Limite de Detecção , Fatores de Tempo
13.
Food Chem ; 338: 127785, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32798825

RESUMO

Patulin (PAT) contaminant causes severe food safety issue throughout apple industry. Although adsorption is the feasible approach to remove PAT, the limited adsorption capacity and separation difficulty of most adsorbent is the major drawback that remains to be overcome. Here GO-SH doped aerogel was prepared and used for removal PAT from apple juice. The intrinsic porous of the aerogel and abundant active sites including -COOH, -NH2 and -SH offered the PAT adsorption capacity of 24.75 µg/mg that superior to most reported adsorbents. Furthermore, it could reduce 89 ± 1.23% PAT in real apple juice without juice quality deterioration and cytotoxicity. Importantly, the aerogel with good mechanical strength and structure stability could endure the complex juice solution so that there was no any residue after convenient separation of the aerogel, which proved that the proposed aerogel was a promising adsorbent to be applied to apple juice industry for PAT removal.


Assuntos
Sucos de Frutas e Vegetais/análise , Grafite/química , Malus/química , Patulina/química , Patulina/isolamento & purificação , Enxofre/química , Adsorção , Contaminação de Alimentos/análise , Géis
14.
J Agric Food Chem ; 69(1): 511-519, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33373219

RESUMO

Gold nanoparticles (AuNPs) are the most commonly used signal materials in lateral flow immunoassay (LFIA). However, the assay sensitivity of traditional AuNP-based LFIA is usually limited by the incomplete competition between free target analytes and immobilized antigens for the binding of AuNP-labeled antibodies. To unfreeze this limitation, here, asymmetric Au-SiO2 Janus NPs (about 66 nm) were designed and synthesized. Au-SiO2 Janus NPs can assemble into snowman-like anisotropic structures and combine two different physicochemical properties at their opposite sides, where the AuNP side mainly possesses the antibody conjugating and signal providing functions and the SiO2 side primarily offers the stable function. In virtue of the unique asymmetric nanostructure, only the AuNP side can interact with target analytes by specific antigen-antibody interactions, which could significantly improve the efficiency of competition. Selecting furazolidone as a model analyte, the immunoassay biosensor showed a limit of detection as low as 0.08 ng/mL, 10-fold decreased than that of the AuNPs-LFIA. Moreover, the Au-SiO2 Janus NP lateral flow immunoassay was well applied in chicken, pork, honey, and beef food samples with visual detection limits of 0.8 ng/g, 0.16 ng/g, 0.4 ng/mL, and 0.16 ng/g, respectively. The Au-SiO2 Janus NPs possess the advantages of both materials, which will broaden their applications as a potential alternative in the rapid and sensitive detection of antibiotic residues.


Assuntos
Antibacterianos/análise , Resíduos de Drogas/análise , Furazolidona/análise , Imunoensaio/métodos , Animais , Bovinos , Galinhas , Contaminação de Alimentos/análise , Ouro/química , Mel/análise , Imunoensaio/instrumentação , Limite de Detecção , Carne/análise , Nanopartículas Metálicas , Dióxido de Silício/química , Suínos
15.
PLoS One ; 10(5): e0127247, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25985075

RESUMO

The influence of environmental attitudes on environmental behaviors has long been discussed. However, few studies have addressed the foundation of such attitudes. In the present study, we explored primitive belief underlying environmental attitudes, i.e., connections with nature, and its relationship with pro-environmental behaviors. Specifically, we used scales, a computerized Implicit Association Test, and a situational simulation experiment to examine both explicit and implicit connections with nature, both deliberate and spontaneous environmental behaviors, and to find correlations between environmental connectedness and environmental behaviors. Results showed that explicit connectedness was positively correlated with deliberate environmental behaviors, while implicit connectedness was positively correlated with spontaneous environmental behaviors. Additionally, explicit and implicit connectedness was independent of each other. In conclusion, the current study confirms the positive role played by connections with nature in promoting environmental behavior, and accordingly suggests means to encourage pro-environmental behavior by enhancing people's connectedness to nature.


Assuntos
Comportamento , Meio Ambiente , Natureza , Adulto , Feminino , Humanos , Masculino , Estudantes , Inquéritos e Questionários , Universidades , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA