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1.
J Environ Sci (China) ; 124: 602-616, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182166

RESUMO

Herein, a novel direct Z-scheme photocatalyst was accomplished by hybridization of 0D MoS2 quantum dots (MSQDs) and 3D honeycomb-like conjugated triazine polymers (CTP) (namely, CTP-MSQD). The unique 0D/3D hierarchical structure significantly enhanced the exposure of active sites and light harvesting property, while the formed p-n junction enabled the direct strong interface coupling without the necessity of any mediators. The optimized CTP-MSQD3 exhibited continuously increased visible-light-driven photocatalytic activity and strong durability both in Cr(VI) reduction and H2 evolution, featured a rate of 0.069 min-1 and 1070 µmol/(hr∙g), respectively, which were 8 times than those of pure 3D-CTP (0.009 min-1 and 129 µmol/(hr∙g)). We believe that this work provides a promising photocatalyst system that combines a 0D/3D hierarchical structure and a Z-scheme charge flow for efficient and stable photocatalytic conversion.

2.
J Hazard Mater ; 442: 130139, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36303361

RESUMO

An important concern during phytoremediation of heavy metal contamination in soils is the risk of leaching of heavy metals before they can be taken up by plants. The most effective method is to use heavy metal stabilizers. However, the stabilization without selectivity will greatly inhibit the phytoremediation effect of all heavy metals. A novel polymer with amino and mercapto groups named as AMP has been prepared as a new exclusive soil stabilizer for Pb. The adsorption of AMP toward Pb belonged to a monolayer adsorption and chemical process. The adsorption capacity of Pb increased with the increase of pH and initial Pb concentration, and obeyed the Langmuir model and pseudo-second-order model, respectively. An amazing maximum adsorption capacity of 588 mg Pb g-1 was reached for AMP when initial concentration was 300 mg Pb L-1, while K2 of 0.594 g mg-1 min-1 was obtained when the initial Pb concentration was 2.0 mg L-1. The distribution coefficient of AMP to Pb in the mixture of five heavy metals was as high as 3110 mL g-1, which was at least 7-fold greater than those of other heavy metals, exhibiting high selective to Pb. AMP showed a fast, large adsorption capacity and good selectivity due to the abundance of sulfhydryl and amino functional groups in the polymer and their interaction with metal ions. The effects of AMP in soil remediation were further tested by a soil column leaching experiment and a pot experiment, and the good stabilization effect of AMP on Pb and the less effect on bioavailability of other heavy metals at recommended doses were verified. This study was expected to solve the problem of leaching risk of the target metal such as Pb in sludge during land use. It provided a new idea of exclusive stabilization to assist phytoremediation of non-target heavy metals by reducing the leaching risk of some special target metal.


Assuntos
Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , Poluentes do Solo/análise , Chumbo , Polímeros , Metais Pesados/análise , Solo , Monofosfato de Adenosina
3.
J Colloid Interface Sci ; 630(Pt A): 430-442, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36265344

RESUMO

Solar energy is becoming the most promising option to mitigate the energy crisis in the future and can be applied in renewable and economical technologies such as water splitting and pollutants degradation. The promotion of the electronic energetic level is considered an efficient method to enhance the photocatalytic performance of semiconductor materials for solar energy conversion. The highly energetic electrons exhibit a remarkable reduction ability by virtue of the electronic spin polarization, which is associated with the conduction band (CB) position. Thus, the regulation of the CB position due to the redistribution of electrons by means of defect engineering presents potential. Here, a series of titanium-based metal-organic frameworks (Ti-based MOFs) named MIL-125-m% containing different extents of defects are reported to enable photocatalytic activity under simulated sunlight and visible light illumination for remarkably enhanced photocatalytic hydrogen evolution and pollutant degradation. The experimental results illustrated that MIL-125-5 % exhibited a superior photocatalytic hydrogen evolution rate (16507.27 µmol·g-1·h-1), much higher than that of MIL-125-0 % (1.444 µmol·g-1·h-1). The excellent photocatalytic performance was attributed to upshift of d-band center, which strengthened the adsorption of H*, facilitating the H2 evolution reaction. In addition, the degradation rate of MIL-125-5 % was up to twice the original rate, for the highly energetic electrons induced by the CB flexibility alleviated the photoinduced electron recombination in defective MIL-125. The strategy of defect engineering provides a new path to control the flexibility of the CB position by electronic spin polarization on adjustable metal-organic frameworks (MOFs), and the photocatalytic effect is changed accordingly.

4.
Carbohydr Polym ; 301(Pt A): 120295, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36436864

RESUMO

Chondroitin sulfate (CS) is widely known for its various biological activities which are closely related to the sulfate substitution and the molecular weight. Effective degradation methods without striping sulfate groups are in a need. In the present study, a photocatalytic degradation method using H2O2 and TiO2 has been developed and it could decrease the average molecular weight of CS into 5 kDa within 6 h. The chemical composition of CS before and after degradation were compared by FT-IR, NMR, etc., and no removement of sulfate group was observed. Then the identification of the oligosaccharides in the degradation product by mass spectroscopy revealed that glucuronic acid or its derivative, arabinuronic acid, was at most of the reducing ends, and the depolymerization mechanism was proposed. Furthermore, the absorption of CS in rats was enhanced by the degradation while the excertion profile of the degradation product was similar to that of CS.


Assuntos
Sulfatos de Condroitina , Peróxido de Hidrogênio , Ratos , Animais , Sulfatos de Condroitina/química , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfatos
5.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 47(10): 1454-1460, 2022 Oct 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-36411697

RESUMO

Presbyopia, a progressive visual difficulty caused by weakened physiological regulation, is one of the main causes of visual impairment in people over 40 years old. Currently, the main methods of correction of presbyopia include optical correction, surgical correction, and drug treatment, which can improve the visual nearness disorder to some extent. Optical correction is the most common way with advantages of safety, which can adjust the lens parameters at any time, while cause kinds of inconvenience in life by wearing and taking off glasses frequently. Surgical intervention, including corneal surgery, lens surgery and scleral surgery, with certain advantages and disadvantages in each operation style. New pharmaceutical agents are expected to be a new and effective method for the treatment of presbyopia, but it lacks multicenter randomized controlled trials and evidence-based medicine evidence to evaluate the safety and effectiveness.

6.
Brain Sci ; 12(11)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36358379

RESUMO

In the event of an acute ischemic stroke, saving the penumbra is the most important aspect of early treatment. The rapid and accurate identification of ischemic penumbra plays a key role in its comprehensive treatment. At present, the identification method and evaluation standard of ischemic penumbra have not been unified. Numerous pieces of software identifying ischemic penumbra have been developed, such as rapid processing of perfusion and diffusion (RAPID), Sphere, Vitrea, and computed tomography perfusion+ (CTP+). The RAPID software, analyzing and integrating multi-mode image data (mainly based on perfusion weighted imaging (PWI) or computed tomography perfusion (CTP) images, shows good performance in identifying ischemic penumbra and has been utilized for the assessment of ischemic penumbra in many ischemic stroke clinical studies, achieving good outcomes and promoting the transition from "time window" to "tissue window" in the treatment of early stage AIS. To obtain a comprehensive understanding of the RAPID software and its accuracy in evaluating ischemic penumbra, this paper reviews the background and development of the RAPID software, summarizes the published acute cerebral infarction trials using the RAPID software, generalizes the threshold parameters in different time windows, and further discusses its application and limitations.

7.
J Hazard Mater ; 444(Pt B): 130428, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36435039

RESUMO

Simultaneous regulation of adsorption and photocatalytic performance of covalent triazine frameworks (CTFs) to achieve efficient control of organic pollution in water is a promising strategy, but remains a formidable challenge. Herein, pyridine linkers were innovatively introduced into pristine CTF (p-CTF) and the bidirectional electron donor-acceptor (EDA) system of contaminant-to-pyridine and pyridine-to-triazine was constructed inside. Experimental results combined with theoretical calculations revealed that pyridine units with π-deficient properties performed as electron acceptors and electron donors in the adsorption and photocatalytic processes, respectively. This special structure provided a directional pathway for electron transfer, which endowed CTFs with excellent adsorption and photocatalytic properties. Compared to p-CTF, pyridine-linked CTF (M-CTF) showed a 16-fold increase in adsorption capacity for naphthalene (973.4 µmol·g-1). Benefiting from the optimized light absorption and electron transfer form (n → π*transition), M-CTF exhibited high regeneration efficiency after adsorption of both bisphenol A (94 % after 4 cycles) and naphthalene (95 % after 4 cycles). Besides, the removal performance of organic micropollutants from natural water showed a great advantage thanks to the bidirectional EDA system. Overall, the present study provides new insights into the optimization of electronic structures for carbon-based environmental functional materials applied to organic pollution control in water.

8.
ACS Appl Mater Interfaces ; 14(47): 53150-53164, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36394639

RESUMO

Membrane capacitive deionization (MCDI) has emerged as a promising electric-field-driven technology for brackish water desalination and specific salt or charged ion separation. The use of carbon-based or pseudocapacitive materials alone for MCDI usually suffers from the drawbacks of low desalination capacity and poor cycling stability due to their limited accessible adsorption sites and obstructed charge-carrier diffusion pathways. Therefore, developing a hybrid electrode material with multiple charge storage mechanisms and continuous electron/ion transport pathways that can synergistically improve its specific capacitance and cycling durability has currently become one of the most critical technical demands. Herein, we developed a novel hierarchically architectured hybrid electrode by first spinning MXene into polyacrylonitrile (PAN)-based carbon nanofibers (MCNFs) to obtain a highly conductive carbon nanocomposite framework. The excellent spatial support structure can effectively prevent the dense packing of Cl-- and DBS--doped polypyrrole (PPy) molecular chains during the following electrodeposition process, which not only ensures the efficient transport of electrons in the continuous hybrid carbon nanofibrous skeleton but also provides abundant accessible sites for ion adsorption and insertion. The obtained self-supporting membrane electrodes (MCNF@PPy+Cl- and MCNF@PPy+DBS-) have the advantages of outstanding specific capacitance (318.4 and 153.9 F/g, respectively), low charge transfer resistance (10.0 and 5.3 Ω, respectively), and excellent cycling performance (78% and 90% capacitance retention ratios, respectively, after 250 electrochemical cycles). Furthermore, the asymmetrical membrane electrodes showed a superior desalination capacity of 91.2 mg g-1 in 500 mg/L NaCl aqueous solution and obvious divalent ion (Ca2+, Mg2+) selective adsorption properties in high-salt water from the cooling towers of thermal power plants.

9.
Artigo em Inglês | MEDLINE | ID: mdl-36385341

RESUMO

Herein, a series of covalent triazine framework/bismuth vanadate (CTF/BiVO4) heterojunction catalysts were prepared using the hydrothermal method. The mechanism of the CTF/BiVO4 heterojunction photocatalyst in the system was examined to provide a theoretical basis for constructing a high-efficiency photocatalysis composite system for removing organic pollutants from water. Compared with CTF and BiVO4 catalysts alone, composite materials have been shown to have significantly higher degradation efficiencies against organic pollutants in water. Moreover, the degradation effect was found to be optimal when the mass ratio of CTF to BiVO4 was 1:1 (1-CTF/BiVO4). On the basis of physicochemical characterization results, it was concluded that the effective construction of CTF/BiVO4 composite photocatalyst material systems and the formation of type II heterojunction structures between CTF and BiVO4 effectively promote the separation of photogenerated carriers and increase the interface charge transfer efficiency.

10.
Plants (Basel) ; 11(20)2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36297732

RESUMO

Soybean is an important food crop in the world. Drought can seriously affect the yield and quality of soybean; however, studies on extreme drought-weak and strong-are absent. In this study, drought-tolerant soybean Heinong 44 (HN44) and sensitive soybean Heinong 65 (HN65) were used as the test varieties, and the effects of strong and weak droughts on the physiological stability of soybean were explored through the drought treatment of soybean at the early flowering stage. The results showed that the contents of malondialdehyde (MDA), hydrogen peroxide (H2O2), and superoxide anions (O2·-) increased with the increase in the degree of drought. The plant height and relative water content decreased, and photosynthesis was inhibited. The activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), and the total antioxidant capacity (T-AOC) showed a trend of first increasing and then decreasing. Through contribution analysis, CAT changed the most, and the role of SOD gradually increased with the aggravation of drought. With the aggravation of drought, the contents of soluble sugar (SSC) and proline (Pro) increased gradually, and the content of soluble protein (SP) increased initially and then decreased. According to contribution analysis, SSC had the highest contribution to osmotic adjustment. SSC and Pro showed an upward trend with the aggravation of drought, indicating that their role in drought was gradually enhanced.

11.
Food Funct ; 13(21): 11262-11272, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36226488

RESUMO

Due to its expanded farming and growing consumption, Caulerpa lentillifera has received extensive attention. In the present study, the physicochemical properties of insoluble dietary fibers from C. lentillifera (CL-IDFs) were evaluated in vitro, and 16S rRNA sequencing analysis as well as non-targeted metabolomics were performed to investigate the hypolipidemic effects of CL-IDFs and their combined supplementation (CL-TDFs, composed of CL-IDFs and soluble polysaccharides of C. lentillifera) in vivo. The results show that CL-IDFs exhibited superior physicochemical capacities on the binding of water, oil, and glucose. In addition, CL-IDF and CL-TDF administration could regulate the gut microbiota, increase acetic and propionic acid levels, and restore the metabolic disorders of amino, fatty, and bile acids in obese mice. Notably, considering the processing cost of C. lentillifera and the equal anti-obesity effects of CL-IDFs and CL-TDFs, fresh whole-food supplementation of C. lentillifera may be a cost-effective way to prevent obesity.


Assuntos
Caulerpa , Microbioma Gastrointestinal , Camundongos , Animais , Caulerpa/química , Dieta Hiperlipídica/efeitos adversos , Fibras na Dieta/farmacologia , RNA Ribossômico 16S/genética , Obesidade/metabolismo , Camundongos Obesos , Camundongos Endogâmicos C57BL
12.
Int J Biol Macromol ; 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36270402

RESUMO

Inadequate dietary fibers intake has been a threat for public health, and its adverse effect and regulatory mechanisms remain unclear. In this study, the protective effect of fucoidan from Scytosiphon lomentaria (SLF) on dietary fibers deficiency (FF)-induced change of physiological functions was analyzed in mice. SLF reduced weight gain and low-density lipoprotein cholesterol, increased high-density lipoprotein cholesterol, but had no effect on food intake and body fat mass in FF-treated mice. Lipidomics analysis showed that SLF modulated lipid metabolism, mainly involving glycerophospholipid and linolenic acid metabolism pathways. In addition, SLF protected against FF-induced colon damages, including the integrity of epithelial cell layer, loss of goblet cells, crypts and glycoproteins, and inflammatory cells infiltration. The underlying mechanisms can be associated with inhibition of oxidative stress, increase of tight junction proteins, and regulation of cytokines profile via nuclear factor kappa B pathway. On the other hand, SLF modulated FF-induced gut microbiota dysbiosis that had close relation with host physiological functions, e.g. increases in Akkermansia, Parabacteroides, Bacteroides and Alistipes. It indicates that SLF can be developed as a prebiotic agent to benefit host health through protecting intestinal barrier and regulating the gut microbiota.

13.
Int J Biol Macromol ; 222(Pt A): 1443-1452, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36191784

RESUMO

Chitosan (CTS)/chitosan oligosaccharide (COS) and whey protein isolate (WPI) have been frequently used as food supplements, but notably, the interaction between the carbohydrate and the protein may affect the digestibility of protein. Thus, the present study focused on effects of the interaction between CTS/COS and WPI on the protein digestibility. A series of chemical and spectroscopic techniques including gel electrophoresis, gel permeation chromatography, Fourier transform-infrared (FT-IR) spectroscopy, intrinsic fluorescence (IF) spectroscopy, and circular dichroism (CD) spectroscopy were applied. According to the findings, both CTS and COS dramatically reduced intestinal digestibility of WPI, resulting in a decrease of DH by 43.33 % and 52.31 %, respectively. The substitution degree of WPI on CTS was 0.87 g WPI/g CTS, and the electrostatic interaction between amine groups of CTS and carboxyl groups of WPI caused changes in WPI's stability, microstructure, and fluorescence intensity. Notably, CTS affected the digestibility of WPI by precipitating protein and enzyme, whereas COS altered WPI's digestibility by decreasing or inactivating enzyme activity. The present study offered a solid scientific foundation for the rational formulations of carbohydrates and proteins in food industry.


Assuntos
Quitosana , Proteínas do Soro do Leite/química , Quitosana/química , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Oligossacarídeos
14.
J Sci Food Agric ; 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36305093

RESUMO

BACKGROUND: Caulerpa lentillifera has received extensive attention regarding expansion of its farming and increasing consumption. In our previous study, the structure of C. lentillifera polysaccharide (CLP) was elucidated. However, little information is available about its health effects. In this study, the anti-obesity effect of CLP was investigated by using a high-fat diet-induced obese mice model with two different supplementation methods. RESULTS: In vitro simulated digestion results showed that CLP significantly decreased the lipid digestibility and induced the lipid droplets aggregation in the intestinal stage to inhibit the absorption of lipids. As revealed by 16S ribosomal RNA sequencing and non-targeted metabolomics, supplement of CLP by both pre-prandial gavage and free feeding patterns effectively prevented mice obesity via ameliorating intestinal flora disturbance and regulating bile acids circulation metabolism. Of note was that CLP administration had no effect on short-chain fatty acids production, suggesting the anti-obesity effect was uncorrelated with their production. Moreover, pre-prandial administration of CLP had a better anti-obesity effect in lowering body weight and serum lipid levels, but the free feeding resulted in a higher α-diversity of gut microbiota. CONCLUSION: The findings of this study indicate that CLP could be a potential anti-obesity nutraceutical and that pre-prandial supplement of CLP may be a better intake method to exhibit its hypolipidemic effect. © 2022 Society of Chemical Industry.

15.
Stem Cells Int ; 2022: 2601764, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248258

RESUMO

A functional vasculature for survival remains a challenge for tissue regeneration, which is indispensable for oxygen and nutrient supply. Utilizing mesenchymal stromal cells (MSCs) to alleviate tissue ischemia and repair dysfunctional or damaged endothelium is a promising strategy. Compared to other populations of MSCs, adipose-derived stromal cells (ASCs) possess a more significant proangiogenic potential and are abundantly available. Cell sheet technology has recently been widely utilized in bone engineering. Compared to conventional methods of seeding seed cell suspension onto biological scaffolds, cell sheet technology prevents cell loss and preserves the extracellular matrix (ECM). Nevertheless, the proangiogenic potential of ASC sheets remains unknown. In this study, rat ASC sheets were constructed, and their macro- and microstructures were examined. In addition, we investigated the effects of ASCs and ASC sheets on the biological properties and angiogenic capacity of endothelial cells (ECs). The results demonstrated that the ASC sheets gradually thickened as the number of cells and ECM increased over time and that the cells were in an active state of secretion. Similar to ASC-CM, the conditioned medium (CM) of ASC sheets could significantly enhance the proliferative capacity of ECs. ASC sheet-CM has significant advantages over ASC-CM in promoting the migration and angiogenesis of ECs, where the exosomes secreted by ASC sheets play an essential role. Therefore, using ASC sheets for therapeutic tissue and organ regeneration angiogenesis may be a valuable strategy.

16.
Front Endocrinol (Lausanne) ; 13: 986131, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36313740

RESUMO

Glaucoma is the leading cause of irreversible blindness. The progressive degeneration of retinal ganglion cells (RGCs) is the major characteristic of glaucoma. Even though the control of intraocular pressure could delay the loss of RGCs, current clinical treatments cannot protect them directly. The overactivation of N-methyl-D-aspartic acid (NMDA) receptors by excess glutamate (Glu) is among the important mechanisms of RGC death in glaucoma progression. Melatonin (MT) is an indole neuroendocrine hormone mainly secreted by the pineal gland. This study aimed to investigate the therapeutic effect of MT on glutamate excitotoxicity of mouse RGCs and R28 cells. The Glu-induced R28 cell excitotoxicity model and NMDA-induced retinal injury model were established. MT was applied to R28 cells and the vitreous cavity of mice by intravitreal injection. Cell counting kit-8 assay and propidium iodide/Hoechst were performed to evaluate cell viability. Reactive oxygen species and glutathione synthesis assays were used to detect the oxidative stress state of R28 cells. Retina immunofluorescence and hematoxylin and eosin staining were applied to assess RGC counts and retinal structure. Flash visual-evoked potential was performed to evaluate visual function in mice. RNA sequencing of the retina was performed to explore the underlying mechanisms of MT protection. Our results found that MT treatment could successfully protect R28 cells from Glu excitotoxicity and decrease reactive oxygen species. Also, MT rescued RGCs from NMDA-induced injury and protected visual function in mice. This study enriches the indications of MT in the treatment of glaucoma, providing practical research ideas for its comprehensive prevention and treatment.


Assuntos
Glaucoma , Melatonina , Fármacos Neuroprotetores , Animais , Camundongos , Células Ganglionares da Retina , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , N-Metilaspartato/toxicidade , N-Metilaspartato/uso terapêutico , Ácido Glutâmico/toxicidade , Ácido Glutâmico/uso terapêutico , Melatonina/farmacologia , Melatonina/uso terapêutico , Espécies Reativas de Oxigênio , Glaucoma/tratamento farmacológico , Receptores de N-Metil-D-Aspartato/uso terapêutico
17.
Adv Nanobiomed Res ; 2(6)2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36051821

RESUMO

Neuroinflammation is one of the hallmarks contributing to Parkinson's Disease (PD) pathology, where microglial activation occurs as one of the earliest events, triggered by extracellular alpha synuclein (aSYN) binding to the CD36 receptor. Here, CD36-binding nanoparticles (NPs) containing synthetic tartaric acid-based amphiphilic polymers (AMs) were rationally designed to inhibit this aSYN-CD36 binding. In silico docking revealed that four AMs with varying alkyl side chain lengths presented differential levels of CD36 binding affinity and that an optimal alkyl chain length would promote the strongest inhibitory activity towards aSYN-CD36 interactions. In vitro competitive binding assays indicated that the inhibitory activity of AM-based NPs plateaued at intermediate side chain lengths of 12- and 18-carbons, supporting the in silico docking predictions. These 12- and 18-carbon length AM NPs also had significantly stronger effects on reducing aSYN internalization and inhibiting the production of the proinflammatory molecules TNF-α and nitric oxide from aSYN-challenged microglia. All four NPs modulated the gene expression of aSYN-challenged microglia, downregulating the expression of the proinflammatory genes TNF, IL-6, and IL-1ß, and upregulating the expression of the anti-inflammatory genes TGF-ß and Arg1. Overall, this work represents a novel polymeric nanotechnology platform that can be used to modulate aSYN-induced microglial activation in PD.

18.
Front Plant Sci ; 13: 982415, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36147232

RESUMO

Soybeans are an important economic crop. As the most widely used growth regulator globally, the molecular mechanism of mepiquat chloride (DPC) in soybean remains unknown. In this study, RNA sequencing technology combined with ultra-performance liquid chromatography and tandem mass spectrometry were used to analyze the changes in the leaf transcriptome and metabolomics of soybean leaves at the seedling stage under DPC stress. The results showed that differentially expressed genes related to photosynthesis and cell wall synthesis were significantly downregulated at the transcriptional level. In addition, the syntheses of gibberellin, zeatin, brassinolide, and other plant hormones were inhibited in the signal transduction pathway of plant hormones, thereby inhibiting plant growth. In contrast, at the metabolic level, the expression levels of flavonoid differential metabolites were significantly increased, and the proportions of flavonoids in the two varieties were 61.5 and 66%, respectively. The combined analysis of transcriptome and metabolomics showed that the differential expressed genes and metabolites were mainly enriched in the isoflavonoid biosynthesis and flavonoid biosynthesis pathways. Principally, DPC inhibited plant growth but improved drought resistance. Our study is the first to report the molecular mechanism of DPC regulation in soybean, providing useful insights into the rational application of DPC in soybean.

19.
Artigo em Inglês | MEDLINE | ID: mdl-36121956

RESUMO

A finite-time output consensus control problem is investigated in this article for an uncertain nonlinear high-order multiagent systems (MASs). For this class of MASs, the order of individual follower is reduced gradually by implementing the immersion and invariance (I&I) control theory repeatedly, and a requirement of solving partial differential equations (PDEs) in I&I control theory is obviated. Furthermore, an I&I-based radial basis function neural network (RBFNN) approximator is developed, where an extra cross term is added in the approximation mechanism, and the form of an update law for weights is transformed into a proportional and integral one. This I&I-based RBFNN approximator does not rely on a cancellation of the perturbation term, and these uncertainties are reconstructed by the I&I manifold adaptively, which is for improvement of approximation behaviors of traditional RBFNNs. On this basis, a distributed adaptive forwarding finite-time output consensus control strategy is proposed by combining a sign function, and the convergence time of the MAS can be adjusted with appropriate finite-time parameters. Finally, two illustrative examples verify the effectiveness of the theoretical claims.

20.
Foods ; 11(18)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36140993

RESUMO

Sulfate polysaccharides, such as heparin sulfate, have been found to have inhibitory activity against SARS-CoV-2. An abalone polysaccharide, AGSP, was deeply sulfate modified using the chlorosulfonic acid/pyridine method, yielding S-AGSP. AGSP and S-AGSP inhibitions of SARS-CoV-2 infection of Vero E6 cells were tested in vitro. The interference of AGSP or S-AGSP on the binding interaction between the SARS-CoV-2 spike protein and angiotensin-converting enzyme was tested using a biolayer interferometry assay. Results showed that S-AGSP, above a concentration of 1.87 µg/mL, significantly inhibited SARS-CoV-2 infection of Vero E6 cells. Compared with AGSP, S-AGSP obviously weakened the affinity between the SARS-CoV-2 spike protein and ACE2. The polysaccharide's sulfate content played a vital role in influencing the binding affinity of spike protein to ACE2. Therefore, S-AGSP has potential as a COVID-19 competitive inhibitor as well as a candidate to be repurposed as a prophylactic COVID-19 therapeutic.

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