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1.
J Hazard Mater ; 473: 134696, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38788586

RESUMO

As medicine and food homology substance, goji berry is consumed worldwide in the form of fresh, dried and juice; however, pesticide residues have become one of the problems that essentially threaten its quality during cultivation and processing. In this study, a total of 75 dried goji berries were sampled from markets across China, and for the determination of 62 analytes, 28 pesticides were identified. Nine pesticides with high detectable rates and residual levels were selected for folia spraying, and their half-lives were found to range from 1.04 to 2.21 d. The processing factors (PFs) of juice were between 0.25 and 1.02, and this was mainly related with their octanol-water partition coefficient (logKow values). Washing could reduce pesticides residues to varying degrees with the removal rates between 17.00% and 74.05%. Sun drying with higher PF values in the range of 0.61-5.91 exhibited more obvious enrichment effect compared to oven drying. Commercial goji berry had cumulative chronic dietary risks with the hazard index (HI) values of 1.61%-4.97%. Its acute risk quotients (HQas) for consumers were 543.32%-585.92% and were mainly due to insecticides. These results provide important references for rationalizing pesticide application during goji berry cultivation and for the improvement of process to ensure food safety.

2.
Talanta ; 274: 126038, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38579419

RESUMO

Herein, a High-Throughput Semi-automated Emulsive Liquid-Liquid Microextraction (HTSA-ELLME) method was developed to detect Succinate Dehydrogenase Inhibitor (SDHI) fungicides in food samples via UHPLC-MS/MS. The Oil-in-Water (O/W) emulsion comprising a hydrophobic extractant and water was dilutable with the aqueous sample solution. Upon injecting the primary emulsion into the sample solution, a secondary O/W emulsion was formed, allowing SDHI fungicides to be extracted. Subsequently, a NaCl-saturated solution was injected in the secondary O/W emulsion as a demulsifier to rapidly separate the extractant, eliminating the need for centrifugation. A 12-channel electronic micropipette was used to achieve a high-throughput semi-automation of the novel sample pretreatment. The linear range was 0.003-0.3 µg L-1 with R2 > 0.998. The limit of detection was 0.001 µg L-1. The HTSA-ELLME method successfully detected SDHI fungicides in water, juice, and alcoholic beverage samples, with recoveries and relative standard deviations of 82.6-106.9% and 0.8-5.8%, respectively. Unlike previously reported liquid-liquid microextraction approaches, the HTSA-ELLME method is the first to be both high-throughput and semi-automated and may aid in designing pesticide pretreatment processes in food samples.


Assuntos
Bebidas Alcoólicas , Sucos de Frutas e Vegetais , Fungicidas Industriais , Microextração em Fase Líquida , Espectrometria de Massas em Tandem , Microextração em Fase Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Fungicidas Industriais/análise , Sucos de Frutas e Vegetais/análise , Bebidas Alcoólicas/análise , Emulsões/química , Água/química , Contaminação de Alimentos/análise , Automação
3.
Environ Pollut ; 343: 123186, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38142029

RESUMO

The second-generation neonicotinoid thiamethoxam, is prevalent in soils because of its extensive application and persistence. However, the comprehensive effects of thiamethoxam residue in soils on cultivated plants are still poorly understood. This study examined variations of growth state, physiological parameters, antioxidant activity, and metabolites in lettuce after thiamethoxam exposure; the removal effects of different washing procedures were also investigated. The results indicated that thiamethoxam in soils significantly increased the fresh weight, seedling height and chlorophyll content in lettuce, and also altered its lipid, carbohydrate, nucleotide and amino acids composition based on untargeted metabolomics. KEGG pathway analysis uncovered a disruption of lipid pathways in lettuce exposed to both low and high concentrations of thiamethoxam treatments. In addition, the terminal residues of thiamethoxam in lettuce were below the corresponding maximum residue limits stipulated for China. The thiamethoxam removal rates achieved by common washing procedures in lettuce ranged from 26.9% to 42.6%. This study thus promotes the understanding of the potential food safety risk caused by residual thiamethoxam in soils.


Assuntos
Inseticidas , Lactuca , Tiametoxam , Inseticidas/análise , Tiazóis/análise , Neonicotinoides/toxicidade , Neonicotinoides/química , Solo/química , Lipídeos
4.
Food Chem ; 405(Pt A): 134803, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36371840

RESUMO

Volatile organic compounds (VOCs) are an important indicator for fungal-infected wheat identification. This work proposes a novel approach for toxigenic Aspergillus flavus infected wheat identification through characteristic VOCs analyzed by nano-composite colorimetric sensors. Nanoparticles of poly styrene-co-acrylic acid (PSA), porous silica nanoparticles (PSN), and metal-organic framework (MOF) were combined with boron dipyrromethene (BODIPY) to fabricate nano-composite colorimetric sensors. The combination mechanisms for nanoparticles and the information extracted from nano-colorimetric sensors by digital images were analyzed in the current work. Furthermore, linear discriminant analysis (LDA) and k-nearest neighbor (KNN) were used comparatively to analyze the data from images, and toxigenic Aspergillus flavus infected wheat samples could be 100.00% correctly identified when using the optimal KNN model. This research contributes to the practical analysis of VOCs and the detection of toxigenic Aspergillus flavus infected wheat.


Assuntos
Aspergillus flavus , Compostos Orgânicos Voláteis , Triticum , Compostos Orgânicos Voláteis/análise , Colorimetria , Tecnologia
5.
Foods ; 11(6)2022 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-35327241

RESUMO

In this work, a new colorimetric sensor based on mesoporous silica nanosphere-modified color-sensitive materials was established for application in monitoring the total volatile basic nitrogen (TVB-N) of oysters. Firstly, mesoporous silica nanospheres (MSNs) were synthesized based on the improved Stober method, then the color-sensitive materials were doped with MSNs. The "before image" and the "after image" of the colorimetric senor array, which was composed of nanocolorimetric-sensitive materials by a charge-coupled device (CCD) camera were then collected. The different values of the before and after image were analyzed by principal component analysis (PCA). Moreover, the error back-propagation artificial neural network (BP-ANN) was used to quantitatively predict the TVB-N values of the oysters. The correlation coefficient of the colorimetric sensor array after being doped with MSNs was greatly improved; the Rc and Rp of BP-ANN were 0.9971 and 0.9628, respectively when the principal components (PCs) were 10. Finally, a paired sample t-test was used to verify the accuracy and applicability of the BP-ANN model. The result shows that the colorimetric-sensitive materials doped with MSNs could improve the sensitivity of the colorimetric sensor array, and this research provides a fast and accurate method to detect the TVB-N values in oysters.

6.
Front Psychol ; 12: 784099, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956006

RESUMO

Time perception plays a fundamental role in people's daily life activities, and it is modulated by changes in environmental contexts. Recent studies have observed that attractive faces generally result in temporal dilation and have proposed increased arousal to account for such dilation. However, there is no direct empirical result to evidence such an account. The aim of the current study, therefore, was to clarify the relationship between arousal and the temporal dilation effect of facial attractiveness by introducing a rating of arousal to test the effect of arousal on temporal dilation (Experiment 1) and by regulating arousal via automatic expression suppression to explore the association between arousal and temporal dilation (Experiment 2). As a result, Experiment 1 found that increased arousal mediated the temporal dilation effect of attractive faces; Experiment 2 showed that the downregulation of arousal attenuated the temporal dilation of attractive faces. These results highlighted the role of increased arousal, which is a dominating mechanism of the temporal dilation effect of attractive faces.

7.
Foods ; 10(9)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34574289

RESUMO

This work presents a novel work for the detection of the freshness of eggs stored at room temperature and refrigerated conditions by the near-infrared (NIR) spectroscopy and multivariate models. The NIR spectroscopy of diffuse transmission and reflection modes was used to compare the quantitative and qualitative investigation of egg freshness. It was found that diffuse transmission is more conducive to the judgment of egg freshness. The linear discriminant analysis model (LDA) for pattern recognition based on the diffuse transmission measurement was employed to analyze egg freshness during storage. NIR diffuse transmission spectroscopy showed great potential for egg storage time discrimination in normal atmospheric conditions. The LDA model discrimination rated up to 91.4% in the prediction set, while only 25.6% of samples were correctly discriminated among eggs in refrigerated storage conditions. Furthermore, NIR spectra, combined with the synergy interval partial least squares (Si-PLS) model, showed excellent ability in egg physical index prediction under normal atmospheric conditions. The root means square error of prediction (RMSEP) values of Haugh unit, yolk index, and weight loss from predictive Si-PLS models were 4.25, 0.031, and 0.005432, respectively.

9.
J Cell Physiol ; 233(6): 5070-5077, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29231977

RESUMO

Bcl-2 homologous antagonist/killer (BAK1) is a critical regulator of mitochondrial apoptosis. Although upregulation of BAK1 induces apoptosis has been established, the underlying molecular mechanism is far from clear. 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS), an organic anion used as a blocker of anion exchangers and chloride channels, has been proved to rescue cell apoptosis both in vitro and in vivo. However, whether DIDS can inhibit BAK1-induced mitochondrial apoptosis remains undefined. Thus, this study aimed to explore whether DIDS could protect BAK1-induced apoptosis through GSK3ß/ß-catenin signaling pathway. The results showed overexpression BAK1 in 293T cells induced mitochondrial apoptosis accompanied by increasing the expression levels of cleaved caspase-9, -3, poly (ADP-ribose) polymerase (PARP) and reducing the MMP. Furthermore, overexpression BAK1 decreased the expression levels of Ser9-GSK3ß and ß-catenin. In addition, lithium chloride (LiCl), an activator of Wnt/ß-catenin signaling pathway, markedly attenuated overexpression BAK1-induced mitochondrial apoptosis by restoring the expression levels of Ser9-GSK3ß and ß-catenin. Finally, DIDS absolutely abolished overexpression BAK1-mediated mitochondrial apoptosis through recovering the expression levels of Ser9-GSK3ß and ß-catenin. Taken together, our results reveal that DIDS blocks overexpression BAK1-induced mitochondrial apoptosis through GSK3ß/ß-catenin pathway.


Assuntos
Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Apoptose/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta/metabolismo , Mitocôndrias/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Células HEK293 , Humanos , Mitocôndrias/enzimologia , Mitocôndrias/patologia , Fosforilação , Regulação para Cima , Proteína Killer-Antagonista Homóloga a bcl-2/genética
10.
Food Chem Toxicol ; 108(Pt A): 148-160, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28757460

RESUMO

Olaquindox, a quinoxaline 1,4-di-N-oxide, is known as an antibacterial agent and feed additive to treat bacterial infections and promote animal growth. However, the potential mechanism of toxicity is still unknown. The present study aims to explore the molecular mechanism of p21 on olaquindox-induced mitochondrial apoptosis and S-phase arrest in human hepatoma G2 cells (HepG2). As a result, olaquindox promoted production of ROS, suppressed the protein expression p21 in p53-independent way and phosphorylated p21. Meanwhile, olaquindox activated AKT and Nrf2/HO-1 pathway, up-regulated Bax/Bcl-2 ratio, disrupted mitochondrial membrane potential (MMP) and subsequently caused cytochrome c release and a cascade activation of caspase, eventually induced apoptosis. Olaquindox could induce S-phase arrest in HepG2 cells involved with the increase of Cyclin A, Cyclin E and CDK 2. Furthermore, knockdown of p21 decreased cell viability, enhanced oxidative stress, aggravated olaquindox-induced mitochondrial apoptosis and S-phase arrest involvement of activating PI3K/AKT and inhibiting Nrf2/HO-1 pathway. PI3K/AKT inhibitor (LY294002) and HO-1inhibitor (ZnPP-IX) both increased olaquindox-induced apoptosis and S-phase arrest. In conclusion, knockdown of p21 increased olaquindox-induced mitochondrial apoptosis and S-phase arrest through further activating PI3K/AKT and inhibiting Nrf2/HO-1pathway. Our study provided new insights into the molecular mechanism of olaquindox and shed light on the role of p21.


Assuntos
Apoptose/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Mitocôndrias/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinoxalinas/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Células Hep G2 , Humanos , Mitocôndrias/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética
11.
Front Psychol ; 7: 639, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27199865

RESUMO

The present study investigated factors influencing Chinese junior school students' study time allocation and the age difference in the effect of habitual responding. Participants were 240 junior school students (120 girls, 120 boys; aged 13-15 years) with half taking part in Experiment 1 and half in Experiment 2, and 240 young adults aged 18-23 years, (120 women and 120 men,) involved in Experiments 3a and 3b, all native Chinese speakers. In Experiments 1 and 3a, Chinese word pairs (e.g., moon-star) were presented on the screen with three items in one array. In each trial, the items were arranged from left to right, either easy, moderate, then difficult, or the reverse. Participants had either 5 s or no time limits to study the word pairs. In Experiments 2 and 3b, word pairs were ordered in a column with the easiest items either at the top or bottom position. Results showed interactions among item difficulty, item order, and time limitation in terms of effects on study time allocation of junior school students. Participants tended to learn the items in order (from left to right and from top to bottom), but the effect of item difficulty was greater than that of item order on item selection. Results indicated that agenda and habitual responding have a combined effect on study time allocation and that the contribution of agenda is greater than that of habitual responding. The effect of habitual responding on the self-paced study and recall performance of junior school students is greater than its effect on young adults, and the study time allocation of junior school students is more likely to be affected by external conditions.

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