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1.
Brief Bioinform ; 24(3)2023 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-36929854

RESUMEN

Chloroplast is a crucial site for photosynthesis in plants. Determining the location and distribution of proteins in subchloroplasts is significant for studying the energy conversion of chloroplasts and regulating the utilization of light energy in crop production. However, the prediction accuracy of the currently developed protein subcellular site predictors is still limited due to the complex protein sequence features and the scarcity of labeled samples. We propose DaDL-SChlo, a multi-location protein subchloroplast localization predictor, which addresses the above problems by fusing pre-trained protein language model deep learning features with traditional handcrafted features and using generative adversarial networks for data augmentation. The experimental results of cross-validation and independent testing show that DaDL-SChlo has greatly improved the prediction performance of protein subchloroplast compared with the state-of-the-art predictors. Specifically, the overall actual accuracy outperforms the state-of-the-art predictors by 10.7% on 10-fold cross-validation and 12.6% on independent testing. DaDL-SChlo is a promising and efficient predictor for protein subchloroplast localization. The datasets and codes of DaDL-SChlo are available at https://github.com/xwanggroup/DaDL-SChlo.


Asunto(s)
Cloroplastos , Lenguaje , Transporte de Proteínas , Cloroplastos/metabolismo , Proyectos de Investigación
2.
J Sci Food Agric ; 104(4): 1920-1927, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-37884466

RESUMEN

BACKGROUND: Butter has been widely used in bakery products and it contains high level of saturated fats. However, excessive consumption of saturated fats would increase the risk of chronic disease. This study was to fabricate water-in-oil (W/O) type bigels as butter replacers to improve the quality attributes of breads. RESULTS: A stable water-in-oil (W/O) type bigel system was fabricated based on mixed oleogelators (rice bran wax and glycerol monostearate) and sodium alginate hydrogel. The ratios of oleogel to hydrogel could significantly affect the stability, microstructure and rheological properties of bigels. All of the bigels exhibited solid-like properties, with increased oleogel fractions, and the network structure of bigel became more compact and orderly with smaller sodium alginate gel particles. Meanwhile, the viscoelastic modulus and firmness of bigel increased, contributing to a higher stability. The bigel dough exhibited lower gel strength and relatively higher extensibility compared to the butter dough. Regardless of oleogel fractions, all the bigel produced bread with a higher specific volume and softer texture than the butter bread. When the oleogel fractions was less than 80%, increasing the oleogel fractions was more beneficial for improving the specific volume, softness and fluffy structure of bread. CONCLUSION: W/O type bigel as butter replacers showed great potential in improving the appearance, structure and textural properties of bread. © 2023 Society of Chemical Industry.


Asunto(s)
Pan , Mantequilla , Hidrogeles/química , Alginatos , Agua , Compuestos Orgánicos
3.
Plant Cell Physiol ; 64(1): 43-54, 2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36201365

RESUMEN

Non-photochemical quenching (NPQ) has been regarded as a safety valve to dissipate excess absorbed light energy not used for photochemistry. However, there exists no general consensus on the photoprotective role of NPQ. In the present study, we quantified the Photosystem II (PSII) photo-susceptibilities (mpi) in the presence of lincomycin, under red light given to five shade-acclimated tree species grown in the field. Photosynthetic energy partitioning theory was applied to investigate the relationships between mpi and each of the regulatory light-induced NPQ [Y(NPQ)], the quantum yield of the constitutive nonregulatory NPQ [Y(NO)] and the PSII photochemical yield in the light-adapted state [Y(PSII)] under different red irradiances. It was found that in the low to moderate irradiance range (50-800 µmol m-2 s-1) when the fraction of open reaction centers (qP) exceeded 0.4, mpi exhibited no association with Y(NPQ), Y(NO) and Y(PSII) across species. However, when qP < 0.4 (1,500 µmol m-2 s-1), there existed positive relationships between mpi and Y(NPQ) or Y(NO) but a negative relationship between mpi and Y(PSII). It is postulated that both Y(NPQ) and Y(NO) contain protective and damage components and that using only Y(NPQ) or Y(NO) metrics to identify the photo-susceptibility of a species is a risk. It seems that qP regulates the balance of the two components for each of Y(NPQ) and Y(NO). Under strong irradiance, when both protective Y(NPQ) and Y(NO) are saturated/depressed, the forward electron flow [i.e. Y(PSII)] acts as the last defense to resist photoinhibition.


Asunto(s)
Procesos Fotoquímicos , Complejo de Proteína del Fotosistema II , Aclimatación , Luz , Fotosíntesis/fisiología , Complejo de Proteína del Fotosistema II/química , Complejo de Proteína del Fotosistema II/metabolismo
4.
J Org Chem ; 88(2): 882-892, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36602382

RESUMEN

The Pd(cod)Cl2-catalyzed alkoxycarbonylation of conjugated dienes to ß,γ-unsaturated esters was approached by both intramolecular phosphinesulfonate L1 and intermolecular PPh3/PTSA in this study. However, the poor solubility of the Pd/L1 complex and the labile monodentate Pd/PPh3 structure restricts the system efficiency, especially for the scale-up application. By contrast, the stable and well-soluble bidentate Xantphos system allows for the quantitative formation of 3-pentenoate (96%) on a gram scale within 6 h in weakly alkaline N-methylpyrrolidone (NMP), which also functions as a basic site to promote the rate-limiting alcoholysis step while reducing the dosage of ligand to a theoretical value.

5.
Physiol Plant ; 175(2): e13880, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36840627

RESUMEN

At the outer canopy, the white leaves of Actinidia kolomikta can turn pink but they stay white in A. polygama. We hypothesized that the different leaf colors in the two Actinidia species may represent different photoprotection strategies. To test the hypothesis, leaf optical spectra, anatomy, chlorophyll a fluorescence, superoxide (O2 ˙- ) concentration, photosystem II photo-susceptibility, and expression of anthocyanin-related genes were investigated. On the adaxial side, light reflectance was the highest for white leaves of A. kolomikta, followed by its pink leaves and white leaves of A. polygama, and the absorptance for white leaves of A. kolomikta was the lowest. Chlorophyll and carotenoid content of white and pink leaves in A. kolomikta were significantly lower than those of A. polygama, while the relative anthocyanin content of pink leaves was the highest. Chloroplasts of palisade cells of white leaves in A. kolomikta were not well developed with a lower maximum quantum efficiency of PSII than the other types of leaves (pink leaves of A. kolomikta and white leaves of A. Polygama at the inner/outer canopy). After high light treatment from the abaxial surface, Fv /Fm decreased to a larger extent for white leaves of A. kolomikta than pink leaf and white leaves of A. polygama, and its non-photochemical quenching was also the lowest. White leaves of A. kolomikta showed higher O2 ˙- concentration compared to pink leaves under the same strong irradiance. The expression levels of anthocyanin biosynthetic genes in pink leaves were higher than in white leaves. These results indicate that white leaves of A. kolomikta apply a reflection strategy for photoprotection, while pink leaves resist photoinhibition via anthocyanin accumulation.


Asunto(s)
Actinidia , Actinidia/metabolismo , Clorofila A/análisis , Antocianinas/metabolismo , Clorofila/metabolismo , Fotosíntesis/fisiología , Complejo de Proteína del Fotosistema II/metabolismo , Hojas de la Planta/metabolismo , Luz
6.
Mol Divers ; 27(2): 571-588, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35666432

RESUMEN

To search a novel lead structure for antiphytopathogenic fungus agent, a series of novel psoralen derivatives possessing sulfonohydrazide or acylthiourea structure were designed and synthesized, and their fungicidal activity against seven phytopathogens was evaluated. Their structures were confirmed by melting points, 1H NMR, 13C NMR and HRMS, and the typical crystal structure was determined by X-ray diffraction for validation. Preliminary fungicidal activity showed that some of the title compounds exhibited certain-to-high fungicidal activity. Compound I-13 exhibited good fungicidal activity against Botrytis cinerea, Cercospora arachidicola and Physalospora piricola with EC50 values of 12.49, 13.22 and 12.12 µg/mL, respectively. Compounds II-9 and II-15 showed over 90% inhibition against B. cinerea at 50 µg/mL in vitro. In particular, II-9 exhibited significant higher fungicidal activity with a lower EC50 value of 9.09 µg/mL than the positive control YZK-C22 (13.41 µg/mL). Our studies found that sulfonohydrazide or acylthiourea-containing psoralen derivatives were promising fungicide leads deserve for further study.


Asunto(s)
Fungicidas Industriales , Furocumarinas , Relación Estructura-Actividad , Antifúngicos/farmacología
7.
Ecotoxicol Environ Saf ; 261: 115102, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37311390

RESUMEN

A modified QuEChERS method coupled with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was established for residue analysis of 39 pollutants (34 commonly used multi-class pesticides and 5 metabolites) in medlar matrices (fresh, dried, and medlar juice). Samples were extracted using water with 0.1 % formic acid: acetonitrile (5: 10, v/v). The phase-out salts and five different cleanup sorbents (including N-propyl ethylenediamine (PSA), octadecyl silane bonded silica gel (C18), graphitized carbon black (GCB), Carbon nanofiber (C-Fiber) and MWCNTs) were investigated to improve the purification efficiency. The Box-Behnken Design (BBD) study was employed for an optimal solution of the volume of extraction solvent, phase-out salt, and the purification sorbents for the analytical method. The average recoveries of the target analytes in the three medlar matrices ranged from 70 % to 119 % with relative standard deviations (RSDs) of 1.0 %-19.9 %. Screening of market samples (fresh and dried medlars) collected from the major producing regions in China showed that 15 pesticides and metabolites were detected in the samples at concentrations of 0.01-2.22 mg/kg, and none of which exceeded the maximum residue limits (MRLs) set in China. The results showed that the risk of food safety by consumption of medlar products caused by the use of pesticides was low. The validated method could be used for rapid and accurate screening of multi-class multi-pesticide residues in Medlar for food safety.


Asunto(s)
Residuos de Plaguicidas , Plaguicidas , Plaguicidas/análisis , Espectrometría de Masas en Tándem/métodos , Residuos de Plaguicidas/análisis , Cromatografía Líquida de Alta Presión , Verduras/química , Extracción en Fase Sólida/métodos
8.
J Clin Lab Anal ; 36(4): e24307, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35202495

RESUMEN

BACKGROUND: Early diagnosis of tuberculosis meningitis (TBM) remains a great challenge during clinical practice. The diagnostic efficacies of cerebrospinal fluid (CSF)-based mycobacterial growth indicator tube (MGIT) culture, modified Ziehl-Neelsen (ZN) staining, Xpert MTB/RIF, and metagenomic next-generation sequencing (mNGS) for TBM remained elusive. METHODS: A total of 216 adult patients with suspicious TBM were retrospectively enrolled in this multi-cohort study. The diagnostic performances for MGIT, modified ZN staining, Xpert MTB/RIF, and mNGS using CSF samples were evaluated. RESULTS: Uniform clinical case definition classified 88 (40.7%) out of 216 patients as the definite TBM, 5 (2.3%) patients as probable TBM cases, and 24 (11.1%) patients as possible TBM cases. The sensitivities of MGIT, modified ZN staining, Xpert MTB/RIF, and mNGS for TBM diagnosis against consensus uniform case definition for definite TBM were 25.0%, 76.1%, 73.9%, and 84.1%, respectively. Negative predictive values (NPVs) were 66.0%, 85.9%, 84.8%, and 90.1%, respectively. The sensitivities of MGIT, modified ZN staining, Xpert MTB/RIF, and mNGS for TBM diagnosis against consensus uniform case definition for definite, probable, and possible TBM were 18.8%, 57.3%, 55.5%, and 63.2%, respectively. Negative predictive values (NPVs) were 51.0%, 66.4%, 65.6%, and 69.7%, respectively. mNGS combined with modified ZN stain and Xpert could cover TBM cases against a composite microbiological reference standard, yielding 100% specificity and 100% NPV. CONCLUSION: Metagenomic next-generation sequencing detected TBM with higher sensitivity than Xpert, ZN staining and MGIT culture, but mNGS cannot be used as a rule-out test. mNGS combined with Xpert or modified ZN staining could enhance the sensitivity of diagnostic tests for TBM.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Meníngea , Adulto , Líquido Cefalorraquídeo/microbiología , Estudios de Cohortes , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Mycobacterium tuberculosis/genética , Estudios Retrospectivos , Sensibilidad y Especificidad , Coloración y Etiquetado , Tuberculosis Meníngea/líquido cefalorraquídeo , Tuberculosis Meníngea/diagnóstico
9.
Biomed Chromatogr ; 36(5): e5342, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35064586

RESUMEN

Trifloxystrobin (TFS) is a widely used strobilurin fungicide and its residues accumulating in animal-derived food could result in potential harm to consumers. By optimization of extraction solvents and cleanup sorbents, a residue analysis method for TFS and its metabolite trifloxystrobin acid (TFSA) was established in milk, eggs and pork based on QuEChERS sample preparation and LC-MS/MS. The calibration curves exhibited good linearity with determination coefficients (R2 ) >0.9930 over the range of 0.5-250 ng/ml for both TFS and TFSA. The recoveries of the two analytes were 81-100% with RSD 3-10% and 76-96% with RSD 2-13%, respectively. The limit of quantification (LOQ) was 1 ng/g for both analytes. The milk, egg and pork samples, 30 each, were collected from the 30 main producing regions in China, and residues of TFS and TFSA were analyzed. The concentrations of both analytes were lower than the corresponding LOQs and maximum residue limits. Long-term dietary risk assessment showed that the hazard quotients were 0.001-0.003%, indicating an absence of unacceptable risks in milk, eggs and pork to the health of common consumers in China.


Asunto(s)
Residuos de Plaguicidas , Carne de Cerdo , Carne Roja , Acetatos , Animales , Cromatografía Liquida , Iminas , Leche/química , Residuos de Plaguicidas/análisis , Carne Roja/análisis , Medición de Riesgo , Estrobilurinas/análisis , Porcinos , Espectrometría de Masas en Tándem
10.
Bull Environ Contam Toxicol ; 108(4): 786-790, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35067727

RESUMEN

A rapid and sensitive analytical method for determination of pyraclostrobin and thifluzamide in cowpea was established based on QuEChERS sample preparation and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Average recoveries of pyraclostrobin and thifluzamide on cowpea were 100%-105% and 99%-105% with RSDs of 1%-5% and 2%-6%, respectively. The storage stability tests showed degradation rates of < 20% for samples stored at - 18℃ within 12 weeks. The field trials at eight locations in China showed that the residues of pyraclostrobin in cowpea at 3 and 5 days after spraying were 0.081-0.49 mg/kg and 0.029-0.48 mg/kg, and the residues of thifluzamide were 0.12-0.46 mg/kg and 0.047-0.50 mg/kg, respectively, which were all lower than the corresponding maximum residue limits in China. The dissipation of both pyraclostrobin and thifluzamide in cowpea were fast with half-lives (T1/2) of 1.5-2.3 days and 1.7-2.4 days. This study provided risk assessment data for establishment of good agricultural practice in cowpea plant.


Asunto(s)
Residuos de Plaguicidas , Vigna , Anilidas , China , Cromatografía Liquida/métodos , Residuos de Plaguicidas/análisis , Medición de Riesgo , Estrobilurinas , Espectrometría de Masas en Tándem/métodos , Tiazoles
11.
Angew Chem Int Ed Engl ; 61(9): e202110657, 2022 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-34851536

RESUMEN

Electroreduction of CO2 on a polymer-modified Cu-based catalyst has shown high multi-electron reduction (>2 e- ) selectivity, however, most of the corresponding current densities are still too small to support industrial applications. In this work, we designed a poly(ionic liquid) (PIL)-based Cu0 -CuI tandem catalyst for the production of C2+ products with both high reaction rate and high selectivity. Remarkably, a high C2+ faradaic efficiency (FE C 2 + ) of 76.1 % with a high partial current density of 304.2 mA cm-2 is obtained. Mechanistic studies reveal the numbers and highly dispersed Cu0 -PIL-CuI interfaces are vital for such reactivity. Specifically, Cu nanoparticles derived Cu0 -PIL interfaces account for high current density and a moderate C2+ selectivity, whereas CuI species derived PIL-CuI interfaces exhibit high activity for C-C coupling with the local enriched *CO intermediate. Furthermore, the presence of the PIL layer promotes the C2+ selectivity by lowering the barrier of C-C coupling.

12.
Curr Issues Mol Biol ; 43(3): 1844-1858, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34889887

RESUMEN

RNA pseudouridine modification is particularly important in a variety of cellular biological and physiological processes. It plays a significant role in understanding RNA functions, RNA structure stabilization, translation processes, etc. To understand its functional mechanisms, it is necessary to accurately identify pseudouridine sites in RNA sequences. Although some computational methods have been proposed for the identification of pseudouridine sites, it is still a challenge to improve the identification accuracy and generalization ability. To address this challenge, a novel feature fusion predictor, named PsoEL-PseU, is proposed for the prediction of pseudouridine sites. Firstly, this study systematically and comprehensively explored different types of feature descriptors and determined six feature descriptors with various properties. To improve the feature representation ability, a binary particle swarm optimizer was used to capture the optimal feature subset for six feature descriptors. Secondly, six individual predictors were trained by using the six optimal feature subsets. Finally, to fuse the effects of all six features, six individual predictors were fused into an ensemble predictor by a parallel fusion strategy. Ten-fold cross-validation on three benchmark datasets indicated that the PsoEL-PseU predictor significantly outperformed the current state-of-the-art predictors. Additionally, the new predictor achieved better accuracy in the independent dataset evaluation-accuracy which is significantly higher than that of its existing counterparts-and the user-friendly webserver developed by the PsoEL-PseU predictor has been made freely accessible.


Asunto(s)
Algoritmos , Biología Computacional/métodos , Aprendizaje Automático , Seudouridina/química , ARN/química , ARN/genética , Bases de Datos Genéticas , Regulación de la Expresión Génica , Reproducibilidad de los Resultados
13.
J Sep Sci ; 44(20): 3860-3869, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34384003

RESUMEN

Methoxyfenozide and metaflumizone are insecticides used on Chinese broccoli to prevent insects and increase yield. However, the residues are potentially harmful to the environment and consumers. In this study, the quick, easy, cheap, effective, rugged, safe method with high-performance liquid chromatography with tandem mass spectrometry was modified and validated for determination of methoxyfenozide and metaflumizone in Chinese broccoli. The clean-up efficiency of different sorbents including C18 , primary secondary amine, graphitized carbon black, and carbon nanofiber was compared. Recoveries of the validated method were 71.8-94.6% with relative standard deviations of 1.5-3.2% and the limits of quantification were 0.01 and 0.005 mg/kg for methoxyfenozide and metaflumizone, respectively. A storage stability test showed almost no degradation of methoxyfenozide in Chinese broccoli, however, the degradation rate of metaflumizone was 22.9% after 10-wk storage at -20°C. In field trials in four producing regions, the dissipation of both methoxyfenozide and metaflumizone in Chinese broccoli was fast, with half-lives of only 1.0-5.1 and 0.7-2.5 days, respectively. Terminal residues after application of the two pesticides were all below 1.0 mg/kg after 5 days.


Asunto(s)
Brassica/química , Hidrazinas/análisis , Hormonas Juveniles/análisis , Residuos de Plaguicidas/análisis , Semicarbazonas/análisis , China , Cromatografía Líquida de Alta Presión , Espectrometría de Masas en Tándem
14.
Bull Environ Contam Toxicol ; 106(6): 1009-1016, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33772599

RESUMEN

Hydrolysis characteristics of a novel 3,4-dichloroisothiazole based fungicide with activating plant defense responses as a candidate plant-activator LY5-24-2 were investigated under different conditions (pH and temperature) using ultra-performance liquid chromatography (UPLC) and quadrupole Time-of-Flight (Q-TOF). The hydrolysis case complied with the first-order kinetic model, with half-lives ranging from 4.8 h to 3.2 days at pH 4, 7, 9 and temperature at 25 and 50℃. One of the hydrolysis metabolite 3,4-dichloroisothiazole-5-carboxylic acid (metabolite 1, M1) was determined and quantified using authentic standard. The other hydrolysate 3-chloro-5-(trifluoromethyl) pyridin-2-amine (metabolite 2, M2) was determined and identified according to accurate mass information, fragmentation patterns and principle component analysis (PCA). By utilizing high-resolution mass spectrometry and multivariate statistical analysis, hydrolysis dynamic of the metabolites was characterized and figured out. This research provided a non-target screening method to analyze hydrolysis metabolites of a new plant-activator and to find its degradation products in aqueous solution.


Asunto(s)
Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Hidrólisis , Cinética , Espectrometría de Masas
15.
Angew Chem Int Ed Engl ; 60(15): 8198-8202, 2021 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-33480082

RESUMEN

Organic ferroelectrics are highly desirable for their light weight, mechanical flexibility and biocompatibility. However, the rational design of organic ferroelectrics has always faced great challenges. Anilinium bromide (AB) has two structures reported in the Cambridge Crystallographic Data Centre, which might be an mmmF2/m type ferroelastic (AB-1). When we studied its ferroelasticity, we were surprised to discover that there was another crystal (AB-2) in H2 O besides this one, and they were very difficult to separate. By changing the solvent, we found that AB-1 crystals could be formed in ethanol, where ferroelastic domains were visualized by polarized light microscopy, and AB-2 crystals could be obtained from various crystallization solvents of methanol, isopropanol, N-butanol, acetonitrile, dimethyl sulfoxide, and N,N-dimethylformamide, which undergo a ferroelectric phase transition with mm2Fm, showing clear ferroelectricity in two phases. To our knowledge, the regulation of ferroelasticity to ferroelectricity by solvent selective effect is unprecedented in the field of ferroelectrics. This work reveals the important role of solvent effect in organic ferroelectrics.

16.
Anal Chem ; 92(11): 7444-7452, 2020 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-32363854

RESUMEN

Pesticides, widely used for pest control and plant growth regulation, have posed a threat to the environment and human health. Conventional methods to analyze pesticide residues are not applied to resource-limited areas because of their high cost, complexity, and requirements for expensive instruments (such as GC/MS and LC/MS). To address these challenges, herein we fabricated colorimetric nanozyme sensor arrays based on heteroatom-doped graphene for detection of aromatic pesticides. The active sites of nanozymes could be differentially masked when different pesticides were adsorbed on the graphene, which in turn resulted in the decrease of their peroxidase-mimicking activities. On the basis of this principle, five pesticides (i.e., lactofen, fluoroxypyr-meptyl, bensulfuron-methyl, fomesafen, and diafenthiuron) from 5 to 500 µM were successfully discriminated by the sensor arrays. In addition, discrimination for different concentrations of each pesticide and different ratios of two mixed pesticides were also demonstrated. The practical application of the sensor arrays was further validated by successfully discriminating the pesticides in soil samples. This work not only provides a facile and cost-effective method to detect pesticides but also makes a positive contribution to food safety and environmental protection.


Asunto(s)
Colorimetría , Grafito/química , Nanoestructuras/química , Peroxidasa/química , Plaguicidas/análisis , Adsorción , Peroxidasa/metabolismo
17.
Ecotoxicol Environ Saf ; 206: 111209, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-32891912

RESUMEN

In this paper, several experiments were carried out to study the environmental behavior and influencing factors of glyphosate (PMG) in peach orchard ecosystem. The results of field experiments showed that PMG and its metabolite aminomethylphosphonic acid (AMPA) were detected in peach tree leaves and peach tree fruits, although PMG was only sprayed on the soil. The residues of PMG and AMPA in peach tree leaves were ~0.1 mg/kg and ~0.5 mg/kg and in peach tree fruits were ~0.01 mg/kg and 0.07-0.11 mg/kg, respectively. By conducting a series of laboratory simulation experiments, the environmental factors affecting the degradation of PMG were screened and evaluated. The results showed that PMG metabolized much faster in loess soil than red soil and black soil (with the DT50 of 11.6 days, 62.4 days, and 34.1 days, respectively). By analyzing the basic properties of the soil, we investigated the effects of pH, moisture content, organic matter (exogenous biochar) and ambient temperature using orthogonal experiments, and the results were further confirmed by microbial experiment. The results showed that alkaline conditions (pH = 7.8/9), high water content (25%) and microorganisms could promote the degradation of PMG. Sterile soil environment had a negative impact on the metabolic behavior of PMG to AMPA.


Asunto(s)
Monitoreo del Ambiente/métodos , Glicina/análogos & derivados , Herbicidas/metabolismo , Organofosfonatos/metabolismo , Prunus persica/crecimiento & desarrollo , Contaminantes del Suelo/metabolismo , Biodegradación Ambiental , China , Ecosistema , Glicina/análisis , Glicina/metabolismo , Herbicidas/análisis , Modelos Teóricos , Organofosfonatos/análisis , Prunus persica/metabolismo , Suelo/química , Contaminantes del Suelo/análisis , Glifosato
18.
Pak J Pharm Sci ; 33(3(Special)): 1383-1388, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-33361027

RESUMEN

This study aims to investigate the effect of hesperidin on CORT-induced apoptosis and oxidative stress of mouse hippocampal nerve cells by up-regulating miR-146a-5p and related mechanism. Hesperidin was applied to CORT-induced HT-22 cells, or HT-22 cells whose expression of mir-146a-5p was up-regulated or down-regulated by CORT. The apoptosis rate was detected by flow cytometry. Expression of Cleaved-caspase-3 protein in cells was detected by Western blot. The levels of MDA, SOD and CAT in the cells were detected by enzyme-linked immunosorbent assay, and the expression of miR-146a-5p was detected by RT-qPCR. The application of hesperidin or up-regulation of miR-146a-5p can reduce the CORT-induced apoptosis rate of HT-22 cells, Cleaved caspase-3 protein expression and MAD content (p<0.05), and increase the activity of SOD and CAT and the expression of miR-146a-5p (p<0.05). In contrast, down-regulation ofmiR-146a-5p can increase the CORT-induced apoptosis rate of HT-22 cells, Cleaved caspase-3 protein expression and MAD content (p<0.05), and decrease the activity of SOD and CAT and the expression of miR-146a-5p (p<0.05). Down-regulation of miR-146a-5p expression can reverse the effects of hesperidin on CORT-induced HT-22 cell apoptosis and oxidative stress. Hesperidin may protect cells from being damaged by up-regulating miR-146a-5p to reduce CORT-induced HT-22 cell apoptosis and oxidative stress.


Asunto(s)
Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Corticosterona/toxicidad , Hesperidina/farmacología , Hipocampo/efectos de los fármacos , MicroARNs/metabolismo , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo/efectos de los fármacos , Animales , Línea Celular , Hipocampo/metabolismo , Hipocampo/patología , Ratones , MicroARNs/genética , Neuronas/metabolismo , Neuronas/patología , Transducción de Señal , Regulación hacia Arriba
19.
Anal Bioanal Chem ; 410(22): 5465-5479, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29411087

RESUMEN

In routine monitoring of foods, reduction of analyzed test portion size generally leads to higher sample throughput, less labor, and lower costs of monitoring, but to meet analytical needs, the test portions still need to accurately represent the original bulk samples. With the intent to determine minimal fit-for-purpose sample size, analyses were conducted for up to 93 incurred and added pesticide residues in 10 common fruits and vegetables processed using different sample comminution equipment. The commodities studied consisted of apple, banana, broccoli, celery, grape, green bean, peach, potato, orange, and squash. A Blixer® was used to chop the bulk samples at room temperature, and test portions of 15, 10, 5, 2, and 1 g were taken for analysis (n = 4 each). Additionally, 40 g subsamples (after freezing) were further comminuted using a cryomill device with liquid nitrogen, and test portions of 5, 2, and 1 g were analyzed (n = 4 each). Both low-pressure gas chromatography-tandem mass spectrometry (LPGC-MS/MS) and ultrahigh-performance liquid chromatography (UHPLC)-MS/MS were used for analysis. An empirical approach was followed to isolate and estimate the measurement uncertainty contribution of each step in the overall method by adding quality control spikes prior to each step. Addition of an internal standard during extraction normalized the sample preparation step to 0% error contribution, and coefficients of variation (CVs) were 6-7% for the analytical steps (LC and GC) and 6-9% for the sample processing techniques. In practice, overall CVs averaged 9-11% among the different analytes, commodities, batches, test portion weights, and analytical and sample processing methods. On average, CVs increased up to 4% and bias 8-12% when using 1-2 g test portions vs. 10-15 g. Graphical abstract Efficient quality control approach to include sample processing.


Asunto(s)
Contaminación de Alimentos/análisis , Frutas/química , Residuos de Plaguicidas/análisis , Verduras/química , Cromatografía Líquida de Alta Presión/métodos , Calidad de los Alimentos , Cromatografía de Gases y Espectrometría de Masas/métodos , Análisis de Peligros y Puntos de Control Críticos/métodos , Control de Calidad , Espectrometría de Masas en Tándem/métodos , Incertidumbre
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