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Oxyresveratrol is one of the active ingredients derived from mulberry branch with strong anti-inflammatory bioactivity. In this research, we want to explore if oxyresveratrol can improve cognitive impairments and episodic-like memory and its mechanism. In LPS-induced BV-2 cells, 25 µM OXY can significantly inhibit the expression of NO and alter the M1/M2 polarization by regulating M1/M2 phenotype makers. In vivo, OXY (50, 100 mg/kg) significantly reversed cognitive impairments and alleviated neuronal injuries caused by neuroinflammation. According to network pharmacology analysis, OXY alleviated neuroinflammation via the PI3K-Akt pathway. In general, the research revealed that OXY can improve cognitive impairments and episodic-like memory through alleviating LPS-induced neuroinflammation and regulating the PI3K-Akt signaling pathway.
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Disfunção Cognitiva , Extratos Vegetais , Proteínas Proto-Oncogênicas c-akt , Estilbenos , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Inflamação/metabolismo , Lipopolissacarídeos/efeitos adversos , Lipopolissacarídeos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Doenças Neuroinflamatórias , Transdução de Sinais , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/metabolismo , Microglia/metabolismoRESUMO
The study of topological photonics has gained significant attention due to its potential application for robust and efficient light manipulation. In this work, we theoretically investigate a two-dimensional photonics crystal that exhibits a topological edge state (TES) and a topological corner state (TCS). Furthermore, we also achieve a coupling between a topological corner state and a trivial cavity (TC), resulting in a phenomenon similar to the electromagnetically induced transparency (EIT) effect. To verify the stability of the EIT-like effect, disorders around TES and TCS are introduced, and the theoretical results show that this structure is immune to the disorders. The achievement of the coupling between topological states can have potential applications in the areas of waveguiding, sensing, and logic gates. It is hoped that this work will contribute to the ongoing efforts in the exploration and utilization of topological photonics.
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We theoretically realize the tunable Fano resonance in a hybrid structure that allows the coupling between Tamm plasmon-polaritons (TPPs) and graphene surface plasmon-polaritons (SPPs). In this coupling system, a distributed Bragg reflector (DBR)/Ag structure is designed to generate the TPP with a narrow resonance, and the graphene SPP is excited by grating coupling with a broad resonance. The overlap of these two kinds of resonances results in the Fano resonance with a high-quality factor close to 1500. The behaviors of the Fano resonance are discussed carefully, and the results show that both the graphene Fermi level and the incidence angle can actively tune the profile of the Fano resonance. Owing to the ultrasharp spectrum of the tunable Fano resonance, our design may offer an alternative strategy for developing various optoelectronic devices such as filters, sensors, and nonlinear and slow-light devices. Finally, as an example of the potential applications, we apply the tunable Fano resonance to the slow-light effect, a high performance slow-light effect can be achieved, and the group delay can reach up to 52 ps.
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A graphene-involved plasmonic lossy system that allows coupling between surface plasmon polaritons and waveguide modes is proposed. The physical mechanism behind the hybrid resonance modes is investigated carefully through finite element method (FEM) simulations and rigorous coupled wave theory (RCWA). We demonstrate that by introducing an incident angle to break the symmetry of the structure, the bound states in the continuum (BIC) evolve to an observable quasi-BIC with new resonance dips, and the generated signals possess a very high Q-factor. Such transformation is investigated carefully by calculating the band structure of the system and the corresponding Q-factors. The results showed that the calculated results from the band structure are consistent with the simulations. In addition, the hybrid plasmonic system allows for switching modulation due to the tunability of graphene, and the max modulation depth of nearly 100% is reached. The outstanding Q-factor and dynamic tunability of this easy-to-fabricate hybrid structure may be helpful in engineering various plasmonic devices, including tunable optical switches, absorbers, sensors, etc.
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We present a monolayer patterned black phosphorus (BP) metamaterial for generating a tunable dual plasmon-induced transparency (PIT). We have derived the expression for the theoretical transmittance by introducing the coupled mode theory (CMT), and the calculated results of the expression highly overlap with the simulation results. The quarterly frequency synchronous switch with two different operating bands is designed by the carrier density and scattering rate on the dual PIT modulation effect. Two parameters were selected as important markers to show the performance of the optical switch: the modulation depth (MD) and the insertion loss (IL). The theoretical analysis of this structure shows that the higher modulation depth (5.45d B
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Three new sesquiterpene polyol ester compounds angulatins S-U, together with three known compounds were isolated from Celastrus angulatus Maxim. According to mainly 1D NMR and 2D NMR analysis, the structures of the new compounds were completely determined as angulatin S (1ß-furoyloxy-2ß,8α-diisobutanoyloxy-9ß-benzoyloxy-15-acetoxy-4α,6α-dihydroxy-ß-dihydroagarofuran), angulatin T (1ß,2ß,6α-triacetoxy-8ß,15-diisobutanoyloxy-9α-benzoyloxy-ß-dihydroagrofuran), and angulatin U (1ß,6α,15-triacetoxy-8ß-isobutanoyloxy-9α-benzoyloxy-ß-dihydroagarofuran).
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Celastrus , Sesquiterpenos , Celastrus/química , Ésteres/química , Estrutura Molecular , Polímeros , Sesquiterpenos/químicaRESUMO
BACKGROUND: Zein particles are unsuitable as stabilizers of Pickering emulsions because of their high hydrophobicity. However, few studies have reported on the use of a strong hydrophilic neutral polysaccharide to regulate its wettability. In this work, zein/pullulan complex particles (ZPPs) were formulated by an anti-solvent method to fabricate Pickering emulsions. RESULTS: The presence of pullulan increased the size, decreased the zeta, and provided excellent resistance to the gravitational separation of zein. Scanning electron microscopy (SEM) revealed that the shape of zein particles changed from spherical as they became aggregated ZPP nanoparticles. Fourier transform infrared (FTIR) spectroscopy indicated that the flocculation phenomenon of ZPPs was related to the hydrogen bond between zein and pullulan. Moreover, the hydrophobicity of zein was modified by hydrophilic pullulan to endow the ZPPs with nearly neutral wettability when the mass ratio was 15:1, allowing for the preparation of stable Pickering emulsions. In contrast to zein, the ZPPs contributed to building a compact interface layer around the droplets and smaller emulsion droplets. Under a certain ZPP concentration, the size and viscosity of emulsion increased with an increase in the oil volume fraction, indicating that the Pickering emulsions stabilized by ZPPs showed better stability against coalescence. Confocal laser scanning microscopy (CLSM) revealed that the ZPPs constructed a dense filling layer on the surface of oil droplets, thus further emphasizing that ZPPs can potentially be used in fabricating Pickering emulsion gels. CONCLUSION: Zein/pullulan complex particles are an excellent Pickering emulsion gel stabilizer that can be used in the delivery system of bioactive substances in food formulations. © 2020 Society of Chemical Industry.
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Emulsões/química , Glucanos/química , Zeína/química , Géis/química , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , MolhabilidadeRESUMO
Two new sesquiterpene pyridine alkaloids, Chinese bittersweet alkaloid A (1) and Chinese bittersweet alkaloid B (2), together with five known compounds 3ß- hydroxyolean-9(11),12-diene, ß-sitosterol, 1ß,2ß,6α,15ß-tetraacetoxy-8ß,9α- dibenzoyloxy-ß-dihydroagarofuran, angulatin A and angulatin J, were isolated from the root barks of Celastrus angulatus. The structures of 1 and 2 were elucidated as 1ß,6α,8ß,9ß-tetraacetoxy-2ß,4α-dihydroxy-15ß-isobutanoyloxy-(3,12)-evoninoyloxy-ß-dihydroagarofuran and 1ß,2ß,6α,8ß,9ß-pentaacetoxy-4α-hydroxy-15ß- isobutanoyloxy- (3,12)- evoninoyloxy-ß-dihydroagarofuran mainly by NMR spectroscopic means.
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Alcaloides , Celastrus , Sesquiterpenos , Estrutura Molecular , PiridinasRESUMO
The lignin-carbohydrate complex (LCC) was isolated from milled wood lignin of 2- and 24-month-old crude bamboo (Neosinocalamus affinis) culms using acetic acid (AcOH) and then characterized. The results have shown that the LCC preparation from 2-month-old bamboo (L2) exhibited a slightly lower molecular weight than the LCC preparation from the 24-month-old bamboo (L24). Further studies using Fourier transform infrared spectroscopy (FT-IR) and heteronuclear single quantum coherence (2D-HSQC) NMR spectra analyses indicate that the LCC preparations included glucuronoarabinoxylan and G-S-H lignin-type with G>S>>H. The content of the S lignin units of LCC in the mature bamboo was always higher than in the young bamboo. Combined with sugar composition analysis, the contents of phenyl glycoside and ether linkages in the L24 preparation were higher than in the L2 preparation; however, there was a reverse relationship of ester LCC bonds in L2 and L24. Lignin-xylan was the main type of LCC linkage in bamboo LCCs. Lignin-lignin linkages in the LCC preparations included ß-ß, ß-5 and ß-1 carbon-to-carbon, as well as ß-O-4 ether linkages, but ß-1 linkages were not present in L2.
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Bambusa/química , Carboidratos/química , Lignina/química , Substâncias Macromoleculares/química , Madeira/química , Ácido Acético/química , Configuração de Carboidratos , Estrutura Molecular , Peso Molecular , Xilanos/químicaRESUMO
BACKGROUND: The spread of multidrug-resistant tuberculosis (MDR-TB) Mycobacterium tuberculosis (M. tuberculosis) strains has been a big challenge to the TB control and prevention in China. Knowledge about patterns of drug resistance in TB high-burden areas of China is crucial to develop appropriate control strategies. We conducted a comprehensive investigation of the resistance pattern of M. tuberculosis in Heilongjiang Province. METHODS: 1427 M. tuberculosis clinical strains were isolated from pulmonary TB patients hospitalized between 2007 and 2012. The susceptibility of the isolates to the first-line anti-TB drugs and the resistance of MDR M. tuberculosis to fluoroquinolones were examined. We also performed a statistical analysis to identify the correlated risk factors for high burden of MDR-TB. RESULTS: The global resistance rates of 2007-2012 to the first-line drugs and MDR were 57.0 and 22.8 %, respectively. Notably, the primary MDR-TB and pan-resistance rates were as high as 13.6 and 5.0 %, respectively. Of MDR M. tuberculosis isolates (2009), approximately 13 % were not susceptible to any of the fluoroquinolones tested. Being age of 35 to 54, high re-treatment proportion, the presence of cavity lesion, and high proportion of shorter hospitalization are correlated with the development of MDR-TB. CONCLUSIONS: The high prevalence of drug resistant, MDR-TB, and fluoroquinolone-resistant MDR-TB is a big concern for TB control. More importantly, in order to control the development of MDR-TB effectively, we need to pay more attention to the primary resistance. Targeting reducing the prevalence of the risk factors may lead to better TB control in China.
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Our study aimed at developing polymer micelles that possess redox sensitivity and excellent controlled release properties. 3,3'-dithiodipropionic acid (DTDPA, Abbreviation in synthetic polymers: SS) was introduced as ROS (Reactive oxygen species)response bond and connecting arm to couple hydroxyethyl starch (HES) with oleanolic acid (OA), resulting in the synthesis of four distinct grafting ratios of HES-SS-OA. FTIR (Fourier Transform infrared spectroscopy) and 1H NMR (1H Nuclear magnetic resonance spectra) were used to verify the triumphant combination of HES-SS-OA. Polymer micelles were found to encapsulate OA in an amorphous form, as indicated by the results of XRD (X-ray diffraction) and DSC (Differential scanning calorimetry). When the OA grafting rate on HES increased from 7.72 % to 11.75 %, the particle size decreased from 297.79 nm to 201.39 nm as the polymer micelles became compact due to enhanced hydrophobicity. In addition, the zeta potential changed from -16.42 mv to -25.78 mv, the PDI (polydispersity index) decreased from 0.3649 to 0.2435, and the critical micelle concentration (CMC) decreased from 0.0955 mg/mL to 0.0123 mg/mL. Results of erythrocyte hemolysis, cytotoxicity and cellular uptake illustrated that HES-SS-OA had excellent biocompatibility and minimal cytotoxicity for AML-12 cells. Disulfide bond breakage of HES-SS-OA in the presence of H2O2 and GSH confirmed the redox sensitivity of the HES-SS-OA micelles and their excellent controlled release properties for OA. These findings suggest that HES-SS-OA can be potentially used in the future as a healthcare drug and medicine for the prevention or adjuvant treatment of inflammation.
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Derivados de Hidroxietil Amido , Micelas , Ácido Oleanólico , Oxirredução , Derivados de Hidroxietil Amido/química , Ácido Oleanólico/química , Polímeros/química , Liberação Controlada de Fármacos , Portadores de Fármacos/química , Humanos , Hemólise/efeitos dos fármacos , Técnicas de Química Sintética , Animais , Tamanho da PartículaRESUMO
Multi-active food packaging was prepared for strawberry fruit preservation where epigallocatechin gallate (EGCG)-containing pectin matrix and natamycin (NATA)-containing chitosan (CS) matrix were utilized to complete LBL electrostatic self-assembly. The results showed that the physicochemical properties of the multi-active packaging were closely related to the addition of NATA and EGCG. It was found that NATA and EGCG were embedded in the CS/pectin matrix through intermolecular hydrogen bonding interactions. The CN/PE 15 % multi-active films prepared based on the spectral stacking theory formed a barrier to UV light in the outer layer, exhibited excellent NATA protection under UV light exposure conditions at different times, and provided long-lasting and sustained bacterial inhibition in the inner layer. In addition, the CN/PE 15 % multi-active packaging extended the shelf life of strawberry at room temperature compared with the control samples. In conclusion, the developed CN/PE 15 % packaging provided potential applications for multi-active food packaging materials.
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Quitosana , Fragaria , Embalagem de Alimentos/métodos , Quitosana/química , Pectinas , Raios UltravioletaRESUMO
As one of the most typical pathogens in fruit postharvest diseases, Alternaria alternata (A. alternata) can produce Alternaria toxins (ATs) aggravating fruit decay and harming human health. In this study, ATs (tenuazonic acid, alternariol monomethyl ether, and alternariol) production was inhibited effectively by 200 and 8000 mg/L MF (methyl ferulate) in vitro and in vivo. 1-Octen-3-ol and 3-octanol were the potential iconic volatile organic compounds of ATs (R2 > 0.99). MF induced oxidative stress, resulting in physiological and metabolic disorders, membrane lipid oxidation and cell damage. It decreased precursors and energy supply by disturbing amino acid metabolism, ABC transporters, citrate cycle, pentose and glucuronate interconversions to regulate ATs synthesis. MF down-regulated the genes related to ATs synthesis (PksJ, AaTAS1, and OmtI), transport (AaMFS1 and MFS), and pathogenicity to affect ATs production and virulence. This study provided a theoretical basis for the control of ATs production.
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Alternaria , Metaboloma , Micotoxinas , Transcriptoma , Alternaria/metabolismo , Alternaria/genética , Alternaria/crescimento & desenvolvimento , Alternaria/química , Micotoxinas/metabolismo , Doenças das Plantas/microbiologia , Ácidos Cumáricos/metabolismo , Ácidos Cumáricos/farmacologiaRESUMO
In this study, we developed a multifunctional chitosan film with visible light-responsive photocatalytic properties by incorporating a novel nanofiller-a nanohybrid particle of poly(tannic acid) (PTA) and TiO2 (TP-NPs). Firstly, the hybridization of TiO2 with PTA not only improved its dispersion but also obtained TP-NPs with smaller band gaps (from 3.11 eV to 1.55 eV) and higher separation efficiency of photogenerated e--h+ (about 1.5-fold enhancement), thereby producing more reactive oxygen species and enhancing the antibacterial efficacy (compared with TiO2, the antibacterial effect of TP-NPs on Staphylococcus aureus and Escherichia coli was heightened by about 2 times under visible light for 1 h). Secondly, TP-NPs were hydrogen bonded with chitosan, strengthening its mechanical and barrier properties, while imparting exceptional antibacterial efficacy. Moreover, the multifunctional properties enabled the active film to effectively delay the quality deterioration of grapes and kiwifruit. Hence, this study presented a multifunctional active packaging film tailored for fruit preservation.
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Inspired by the citrus oil gland and cuticular wax, a multifunctional material that stably and continuously released the carvacrol and provided physical defenses was developed to address issues of fresh-cut fruits to microbial infestation and moisture loss. The results confirmed that low molecular weight and loose structure of starch nanoparticles prepared by the ultrasound-assisted Fenton system were preferable for octenyl succinic anhydride modification compared to native starch, achieving a higher degree of substitution (increased by 18.59 %), utilizing in preparing nanoemulsions (NEs) for encapsulating carvacrol (at 5 % level: 81.58 %). Furthermore, the NEs-based gelatin (G) film improved with surface hydrophobic modification by myristic acid (MA) successfully replicated the citrus oil gland and cuticular wax, providing superior antioxidant (enhanced by 3-4 times) and antimicrobial properties (95.99 % and 84.97 % against Staphylococcus aureus and Escherichia coli respectively), as well as the exceptional UV shielding (nearly 0 transmittance in the UV region), mechanical (72 % increase in tensile strength), and hydrophobic (WCA 133.63°). Moreover, the 5%NE-G@MA film inhibited foodborne microbial growth (reduced by 50 %) and water loss (controlled below 15 %), extending the shelf life of fresh-cut navel orange and kiwi. Thus, the multifunctional film was a potential shield for preserving perishable fresh-cut products.
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Citrus , Emulsões , Escherichia coli , Frutas , Gelatina , Nanopartículas , Staphylococcus aureus , Amido , Ceras , Gelatina/química , Nanopartículas/química , Citrus/química , Emulsões/química , Amido/química , Amido/análogos & derivados , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Frutas/química , Ceras/química , Antioxidantes/química , Antioxidantes/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Interações Hidrofóbicas e Hidrofílicas , Cimenos/química , Cimenos/farmacologia , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Ácido Mirístico/química , Ácido Mirístico/farmacologia , Conservação de Alimentos/métodosRESUMO
Pectin, a natural polysaccharide, holds versatile applications in food and pharmaceuticals. However, there is a need for further exploration into extracting novel functional fractions and characterizing them thoroughly. In this study, a sequential extraction approach was used to obtain three distinct lemon pectin (LP) fractions from lemon peels (Citrus Eureka): LP extracted with sodium acetate (LP-SA), LP extracted with ethylenediaminetetraacetic acid (LP-EDTA), and LP extracted with sodium carbonate and sodium borohydride (LP-SS). Comprehensive analysis revealed low methyl-esterification in all fractions. LP-SA and LP-SS displayed characteristics of rhamnogalacturonan-I type pectin, while LP-EDTA mainly consisted of homogalacturonan pectin. Notably, LP-SA formed self-aggregated particles with rough surfaces, LP-EDTA showed interlocking linear structures with smooth planes, and LP-SS exhibited branch chain structures with smooth surfaces. Bioactivity analysis indicated that LP-SA had significant apparent viscosity and ABTS radical scavenging activity, while both LP-EDTA and LP-SS showed excellent thermal stability according to thermogravimetric analysis (TGA). Furthermore, LP-SS exhibited remarkable gel-forming ability and significant hydroxyl free radicals scavenging activity. In conclusion, this study presents a novel method for extracting various lemon pectin fractions with unique structural and bioactive properties, contributing insights for advanced applications in the food and pharmaceutical sectors.
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Antioxidantes , Citrus , Pectinas , Pectinas/química , Pectinas/isolamento & purificação , Citrus/química , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Fenômenos Químicos , Viscosidade , Frutas/química , Extratos Vegetais/química , Extratos Vegetais/farmacologiaRESUMO
Introduction: The incorporation of green manures substantially enhances the conversion of external phosphorus (P) fertilizers and soil-reserved P into forms readily available to plants. The study aims to evaluate the influence of green manure additions on soil phosphorus dynamics and citrus growth, considering different green manure species and initial soil phosphorus levels. Additionally, the research seeks to elucidate the microbiological mechanisms underlying the observed effects. Methods: A citrus pot experiment was conducted under both P-surplus (1.50 g·P·kg-1) and P-deficient (0.17 g·P·kg-1) soils with incorporating legume (Leg), non-legume (Non-Leg) or no green manure residues (CK), and 18O-P labeled KH2PO4 (0.5 g, containing 80 δ18Op) was additionally introduced to trace the turnover characteristics of chemical P fertilizer mediated by soil microorganisms. Results and discussion: In P-surplus soil, compared with the CK treatment, the Leg treatment significantly increased soil H2O-Pi (13.6%), NaHCO3-Po (8.9%), NaOH-Pi (9.5%) and NaOH-Po (30.0%) content. It also promoted rapid turnover of P sources into H2O-Pi and NaHCO3-Pi pools by enhancing the phoC (576.6%) gene abundance. In contrast, the Non-Leg treatment significantly augmented soil H2O-Pi (9.2%) and NaHCO3-Po (8.5%) content, facilitating the turnover of P sources into NaHCO3-Pi pools. Under P-deficient soil conditions, compared with the CK treatment, the Leg treatment notably raised soil H2O-Pi (150.0%), NaHCO3-Pi (66.3%), NaHCO3-Po (34.8%) and NaOH-Pi (59.0%) content, contributing to the transfer of P sources into NaHCO3-Pi and NaOH-Pi pools. This effect was achieved through elevated ALP (33.8%) and ACP (12.9%) activities and increased pqqC (48.1%), phoC (42.9%), phoD (21.7%), and bpp (27.4%) gene abundances. The Non-Leg treatment, on the other hand, led to significant increases in soil NaHCO3-Pi (299.0%) and NaHCO3-Po (132.6%) content, thereby facilitating the turnover of P sources into NaHCO3-Pi and NaOH-Pi pools, except for the phoC gene abundance. Both Leg and Non-Leg treatments significantly improved citrus growth (7.3-20.0%) and P uptake (15.4-42.1%) in P-deficient soil but yielded no substantial effects in P-surplus soil. In summary, introducing green manure crops, particularly legume green manure, emerges as a valuable approach to enhance soil P availability and foster fruit tree growth in orchard production.
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Electronic cigarettes have become a purported safer alternative to the conventional cigarettes in recent years. Nicotine is the main component of electronic cigarettes, and other nicotinic compounds are synthesized as alternatives to nicotine. However, scientific data on the potential health effects of electronic cigarettes are scarce. Herein, we evaluated the cytotoxicity of nicotine and its analog 6-methyl nicotine (6-MN) on human bronchial epithelial cells (BEAS-2B cells) in vitro. Furthermore, we performed transcriptome sequencing to systematically assess the effects of nicotine and 6-MN on BEAS-2B cells. The cytotoxicity assay revealed that BEAS-2B cells were more sensitive to 6-MN than to nicotine. Transcriptome sequencing revealed 1208 differentially expressed cancer-related proteins (CRP) in the 6-MN groups relative to that with CRP in the control group. In addition, 6-MN had a greater negative effect on the CRP expression than nicotine. Bioinformatic analysis revealed that the differentially expressed genes and proteins in the 6-MN group were significantly enriched in the cancer-related pathways, unlike those in the nicotine group. Further validations of some lung cancer-related proteins, such as NF-κB p65, EGFR, and MET, were conducted by immunoblotting and real-time PCR, which revealed that 6-MN may have a greater negative effect on tumor development and metastasis than nicotine. Taken together, our findings suggest that new electronic cigarettes with 6-MN might offer some advantages over conventional electronic cigarettes containing nicotine.
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Sistemas Eletrônicos de Liberação de Nicotina , Neoplasias Pulmonares , Humanos , Nicotina/toxicidade , Brônquios , Carcinógenos/toxicidade , Transcriptoma , Células Epiteliais , Neoplasias Pulmonares/metabolismo , CarcinogêneseRESUMO
Cuticle wax is closely related to fruit quality during storage. In this study, changes in epidermal wax morphology, composition, and genes regulation induced by heat shock (HT), 1-methylcyclopropene (1-MCP) or their combination (HT + 1-MCP) were investigated in jujube fruit during cold storage. HT, 1-MCP, or HT + 1-MCP caused a smoother wax layer and fewer micro-cracks compared to the control (CK) during cold storage. It was confirmed that acids and terpenoids were the main wax components by gas chromatography-mass spectrometry. HT + 1-MCP and 1-MCP treatments could significantly increase (p < 0.05) the wax content at 45 d of cold storage. The transcriptomics results indicated that HT + 1-MCP treatment up-regulated FATB, FATB, FAB2, FAD2 and CYP716A, and maintained the wax content of jujube fruit during cold storage. These results could provide new perspective for regulating the cuticle characteristics to extend the shelf life of jujube fruit.
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Armazenamento de Alimentos , Transcriptoma , Cromatografia Gasosa-Espectrometria de Massas , Metabolômica , Resposta ao Choque TérmicoRESUMO
Ultrasonication (US)-assisted Fenton-system (US-Fenton) with different US time was developed for synthesizing chitosan (CS)-ferulic acid (FA) conjugates. The optimal US-Fenton for a suitable time was selected for preparing a film with CS-FA conjugate and its structural, functional, rheological, and physical properties were also investigated. Compared with Fenton-system, US-Fenton enhanced the grafting ratio of the conjugates, which increased firstly and then decreased as US time. The conjugate obtained by US-Fenton for 1 min (FUS1) possessed the highest grafting ratio (121.28 mg FA/g) and its grafting time was also shortened from 12 h to 1 min contrasted with Fenton grafted method. Structural characterization results showed that FA was conjugated on CS via ester and amide bonds with decreased crystallinity. Scanning electron microscopy and molecular weight analysis indicated that the degradation degree of CS-FA conjugates increased with US time. The DPPH and ABTS radical-scavenging activities of FUS1 were the closest to ascorbic acid, and it also showed the best antibacterial effect among the test conjugates. Accordingly, FUS1 was selected to obtain the film for contrasting with CS film. FUS1 film solution exhibited a decreased viscosity. In comparison to CS film, UV transmittance of FUS1 film approached zero, and its moisture, oxygen, and carbon dioxide permeabilities significantly decreased (P < 0.05). Moreover, its water solubility and tensile strength increased by 58.09% and 25.72% than those of CS film, respectively. Therefore, US-Fenton for 1 min could be a promising method for efficiently preparing active food package materials and FUS1 film possessed broad application prospects.