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The rationally designing and constructing atomic-level heterointerface of two-dimensional (2D) chalcogenides is highly desirable to overcome the sluggish H2O-activation process toward efficient solar-driven hydrogen evolution. Herein, a novel in-plane 2D/2D molybdenum disulfide-rhenium disulfide (ReS2-MoS2) heterostructure is well-designed to induce the charge self-regulation of active site by forming electron-enriched Re(4-δ)+ and electron-deficient S(2-δ)- sites, thus collectively facilitating the activation of adsorbed H2O molecules and its subsequent H2 evolution. Furthermore, the obtained in-plane heterogenous ReS2-MoS2 nanosheet can powerfully transfer photoexcited electrons to inhibit photocarrier recombination as observed by advanced Kelvin probe measurement (KPFM), in-situ X-ray photoelectron spectroscopy (XPS) and femtosecond transient absorption spectroscopy (fs-TAS). As expected, the obtained ReS2-MoS2/TiO2 photocatalyst achieves an outperformed H2-generation rate of 6878.3 µmol h-1 g-1 with visualizing H2 bubbles in alkaline/neutral conditions. This work about in-plane 2D/2D heterostructure with strong free-electron interaction provides a promising strategy for designing novel and efficient catalysts for various applications.
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BACKGROUND: The objective of this study was to analyze the causal relationship between Neuroticism and aortic aneurysm using Mendelian randomization (MR). The study aimed to establish a foundation for the development of effective prevention and treatment strategies. METHODS: Genetic association data for Neuroticism were obtained from the UK Biobank, which included 393,411 individuals and 11,968,760 single nucleotide polymorphisms (SNPs). Genetic association data for aortic aneurysm were obtained from a genome-wide association study (GWAS), which included 479,194 individuals and 24,191,825 SNPs. Heterogeneity was assessed using the Cochran's Q statistic test. The study also utilized the MR Pleiotropy RESidual Sum and Outlier (Mr-PRESSO) test, as well as the MR-Egger regression method, to examine horizontal pleiotropy and determine the reliability of the findings through the leave-one-out method. RESULTS: Forward MR analysis showed that the risk of aortic aneurysm was elevated in individuals with genetically predicted Neuroticism compared to those without Neuroticism (OR = 1.1315, 95 % CI: 1.0269-1.2468; P = 0.0126). The Cochran's Q test showed no heterogeneity (P > 0.05), and the MR-PRESSO test did not identify instrumental variables of horizontal pleiotropy (P > 0.05). The MR analysis remained robust after removing SNPs one by one. Inverse MR analysis did not observe an association between aortic aneurysm and having Neuroticism OR = 1.030, 95 % CI: 0.9459-1.118, P = 0.488). CONCLUSION: Our study has established a clear causal relationship between genetically determined Neuroticism and the development of aortic aneurysms. It is therefore important to intensify screening and prevention efforts for aortic aneurysms in neurotic patients. It also opens new avenues for exploring the disease's pathogenesis.
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Aneurisma de la Aorta , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Neuroticismo , Polimorfismo de Nucleótido Simple , Humanos , Aneurisma de la Aorta/genética , Aneurisma de la Aorta/epidemiología , Predisposición Genética a la Enfermedad , Factores de Riesgo , Masculino , Femenino , Reino Unido/epidemiologíaRESUMEN
This study successfully prepared an edible packaging film that rapidly dissolves in water by utilizing a combination of κ-carrageenan, carboxymethyl starch, and gum ghatti. We investigated the influence of these three materials on the microstructure and physical properties of the film, as well as the impact of the film's dissolution on the stability of beverages. SEM, FTIR, and XRD analyses revealed that the κ-carrageenan, carboxymethyl starch, and gum ghatti primarily interacted through hydrogen bonding, resulting in a more uniform and dense film structure. Surface hydrophilicity and swelling tests indicated an increased presence of hydrophilic groups in the composite film. The inclusion of carboxymethyl starch and gum ghatti significantly improves the film's physical properties, resulting in a notable reduction in water solubility time, an increase in elongation at break from 19.5 % to 26.0 %, a rise in the contact angle from 49.1° to 67.0°, and a decrease in water vapor permeability from 7.5 × 10-10 to 6.2 × 10-10 g/m·s·Pa. Furthermore, coffee packaging bags made from this composite film dissolved entirely in hot water in just 40 s. Dissolving these bags significantly improved the stability of instant coffee, reducing centrifugal sedimentation from 3.8 % to 1.7 %. This study highlights the substantial potential of the κ-carrageenan/carboxymethyl starch/gum ghatti composite film as a packaging material for solid beverages.
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Carragenina , Café , Películas Comestibles , Embalaje de Alimentos , Gomas de Plantas , Solubilidad , Almidón , Agua , Carragenina/química , Almidón/química , Almidón/análogos & derivados , Embalaje de Alimentos/métodos , Agua/química , Café/química , Gomas de Plantas/química , Polvos , Permeabilidad , Vapor , Interacciones Hidrofóbicas e HidrofílicasRESUMEN
BACKGROUND: ß-adrenergic receptor (ß-AR) overactivation is a major pathological cue associated with cardiac injury and diseases. AMPK (AMP-activated protein kinase), a conserved energy sensor, regulates energy metabolism and is cardioprotective. However, whether AMPK exerts cardioprotective effects via regulating the signaling pathway downstream of ß-AR remains unclear. METHODS: Using immunoprecipitation, mass spectrometry, site-specific mutation, in vitro kinase assay, and in vivo animal studies, we determined whether AMPK phosphorylates ß-arrestin-1 at serine (Ser) 330. Wild-type mice and mice with site-specific mutagenesis (S330A knock-in [KI]/S330D KI) were subcutaneously injected with the ß-AR agonist isoproterenol (5 mg/kg) to evaluate the causality between ß-adrenergic insult and ß-arrestin-1 Ser330 phosphorylation. Cardiac transcriptomics was used to identify changes in gene expression from ß-arrestin-1-S330A/S330D mutation and ß-adrenergic insult. RESULTS: Metformin could decrease cAMP/PKA (protein kinase A) signaling induced by isoproterenol. AMPK bound to ß-arrestin-1 and phosphorylated Ser330 with the highest phosphorylated mass spectrometry score. AMPK activation promoted ß-arrestin-1 Ser330 phosphorylation in vitro and in vivo. Neonatal mouse cardiomyocytes overexpressing ß-arrestin-1-S330D (active form) inhibited the ß-AR/cAMP/PKA axis by increasing PDE (phosphodiesterase) 4 expression and activity. Cardiac transcriptomics revealed that the differentially expressed genes between isoproterenol-treated S330A KI and S330D KI mice were mainly involved in immune processes and inflammatory response. ß-arrestin-1 Ser330 phosphorylation inhibited isoproterenol-induced reactive oxygen species production and NLRP3 (NOD-like receptor protein 3) inflammasome activation in neonatal mouse cardiomyocytes. In S330D KI mice, the ß-AR-activated cAMP/PKA pathways were attenuated, leading to repressed inflammasome activation, reduced expression of proinflammatory cytokines, and mitigated macrophage infiltration. Compared with S330A KI mice, S330D KI mice showed diminished cardiac fibrosis and improved cardiac function upon isoproterenol exposure. However, the cardiac protection exerted by AMPK was abolished in S330A KI mice. CONCLUSIONS: AMPK phosphorylation of ß-arrestin-1 Ser330 potentiated PDE4 expression and activity, thereby inhibiting ß-AR/cAMP/PKA activation. Subsequently, ß-arrestin-1 Ser330 phosphorylation blocks ß-AR-induced cardiac inflammasome activation and remodeling.
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Proteínas Quinasas Activadas por AMP , Isoproterenol , Miocitos Cardíacos , beta-Arrestina 1 , Animales , Fosforilación , beta-Arrestina 1/metabolismo , beta-Arrestina 1/genética , Ratones , Proteínas Quinasas Activadas por AMP/metabolismo , Isoproterenol/toxicidad , Isoproterenol/farmacología , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/patología , Ratones Endogámicos C57BL , Masculino , Receptores Adrenérgicos beta/metabolismo , Serina/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Agonistas Adrenérgicos beta/farmacología , Agonistas Adrenérgicos beta/toxicidad , Células Cultivadas , Transducción de Señal , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 4/metabolismo , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 4/genética , HumanosRESUMEN
Alginate is the most abundant polysaccharide compound in brown algae, which is widely used in various fields. At present, the determination of the content of alginate is mostly carried out using sulfuric acid and trifluoroacetic acid hydrolysis followed by the determination of the content, but the results are not satisfactory, and there are problems such as low hydrolysis degree and low recovery rate. Therefore, in this study, based on the optimization of high performance liquid chromatographic conditions for pre-column derivatization of 1-phenyl-3-methyl-5-pyrazolone (PMP), the hydrolysis effects of sulfuric acid, trifluoroacetic acid (TFA), oxalic acid, and formic acid were compared and the hydrolysis conditions were optimized. The results showed that formic acid was the best hydrolyzing acid. The optimal hydrolysis conditions were 95 % formic acid at 110 °C for 10 h. The hydrolysis effect was stable, with high recovery and low destruction of monosaccharides, which made it possible to introduce formic acid into the subsequent polysaccharide hydrolysis. The pre-column derivatization high performance liquid chromatography method established in this study was accurate and reliable, and the hydrolysis acid with better effect was screened, which provided a theoretical basis for the subsequent determination of alginate content.
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The aim of the present study was to identify differentially expressed proteins in the lymph fluid of rabbits with breast cancer lymphatic metastasis compared with healthy rabbits and to analyze and verify these proteins using proteomics technologies. In the process of breast cancer metastasis, the composition of the lymph fluid will also change. Rabbits with breast cancer lymph node metastasis and normal rabbits were selected for analysis. Lymph fluid was extracted under the guidance of percutaneous contrast-enhanced ultrasound. Label-free quantitative proteomics was used to detect and compare differences between the rabbit cancer model and healthy rabbits and differential protein expression results were obtained. Bioinformatics analysis was performed using Kyoto Encyclopedia of Genes and Genomes and Gene Ontology analysis software, selecting the most significantly differentially expressed proteins. Finally, parallel reaction monitoring technology was applied for validation. A total of 547 significantly differentially expressed proteins were found in the present study, which included 371 upregulated proteins and 176 downregulated proteins. The aforementioned genes were mainly involved in various cellular and metabolic pathways, including upregulated proteins, such as biliverdin reductase A and isocitrate dehydrogenase 2 and downregulated proteins, such as pyridoxal kinase. The upregulated proteins protein disulfide-isomerase 3, protein kinase cAMP-dependent type I regulatory subunit α and ATP-binding cassette sub-family C member 4 participated in immune regulation, endocrine regulation and anti-tumor drug resistance regulation, respectively. Compared with healthy rabbits, rabbits with breast cancer metastasis differentially expressed of a number of different proteins in their lymph, which participate in the pathophysiological process of tumor occurrence and metastasis. Through further research, these differential proteins can be used as predictive indicators of breast cancer metastasis and new therapeutic targets.
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Electron density manipulation of active sites in cocatalysts is of great essential to realize the optimal hydrogen adsorption/desorption behavior for constructing high-efficient H2 -evolution photocatalyst. Herein, a strategy about weakening metal-metal bond strength to directionally optimize the electron density of channel-sulfur(S) sites in 1T' Re1- x Mox S2 cocatalyst is clarified to improve their hydrogen adsorption strength (SâH bond) for rapid H2 -production reaction. In this case, the ultrathin Re1- x Mox S2 nanosheet is in situ anchored on the TiO2 surface to form Re1- x Mox S2 /TiO2 photocatalyst by a facial molten salt method. Remarkably, numerous visual H2 bubbles are constantly generated on the optimal Re0.92 Mo0.08 S2 /TiO2 sample with a 10.56 mmol g-1 h-1 rate (apparent quantum efficiency is about 50.6%), which is 2.6 times higher than that of traditional ReS2 /TiO2 sample. Density functional theory and in situ/ex situ X-ray photoelectron spectroscopy results collectively demonstrate that the weakened ReâRe bond strength via Mo introduction can induce the formation of unique electron-deficient channel-S sites with suitable electron density, which yield thermoneutral SâH bonds to realize superior interfacial H2 -generation performance. This work provides fundamental guidance on purposely optimizing the electronic state of active sites by manipulating the intrinsic bonding structure, which opens an avenue for designing efficacious photocatalytic materials.
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Our previous studies have evaluated the bioactivities of a fucoidan isolated from Sargassum fusiforme (SF-F). To further investigate the health benefit of SF-F, in the present study, the protective effect of SF-F against ethanol (EtOH)-induced oxidative damage has been evaluated in in vitro and in vivo models. SF-F effectively improved the viability of EtOH-treated Chang liver cells by suppressing apoptosis. In addition, the in vivo test results indicate that SF-F significantly and dose-dependently increased the survival rate of zebrafish treated with EtOH. Further research results show that this action works through decreasing cell death via reduced lipid peroxidation by scavenging intracellular reactive oxygen species in EtOH-stimulated zebrafish. These results indicate that SF-F effectively protected Chang liver cells and zebrafish against EtOH-induced oxidative damage and suggest the potential of SF-F to be used as an ingredient in the functional food industry.
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In our previous research, we investigated the anti-inflammatory activity of the agaro-oligosaccharides prepared from the agar of Gracilaria lemaneiformis (AO). In the present study, in order to further explore the bioactivities of AO, the antioxidant activity of AO was investigated in vitro in Vero cells and in vivo in zebrafish. AO scavenged alkyl, 1,1-diphenyl-2-picrylhydrazyl, and hydroxyl radicals at the IC50 value of 4.86 ± 0.13, 3.02 ± 0.44, and 1.33 ± 0.05 mg/mL, respectively. AO significantly suppressed hydrogen peroxide (H2O2)-stimulated oxidative damage by improving cell viability. This happened via suppressing apoptosis by scavenging intracellular reactive oxygen species (ROS). Furthermore, the in vivo results displayed that AO protected zebrafish against H2O2-stimulated oxidative damage by reducing the levels of intracellular ROS, cell death, and lipid peroxidation in a dose-dependent manner. These results indicate that AO effectively alleviated in vitro and in vivo oxidative damage stimulated by H2O2, and suggest the potential of AO in the cosmetic and functional food industries.
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Fucoidans isolated from brown seaweeds are potential ingredients in the cosmetic industry. In our preosvious study, a fucoidan was isolated from the brown seaweed Turbinaria ornata (TO-F10) and the anti-inflammatory effect of TO-F10 was evaluated. In order to further explore the potential of TO-F10 in cosmetics, in the present study, antioxidant and photoprotective effects of TO-F10 were investigated. TO-F10 remarkably protected Vero cells against AAPH-stimulated cell death by reducing apoptosis via scavenging intracellular reactive oxygen species (ROS). In addition, TO-F10 increased the survival rate of AAPH-treated zebrafish by suppressing oxidative stress displayed in reducing the levels of ROS, cell death, and lipid peroxidation. Furthermore, TO-F10 effectively attenuated UVB-induced in vitro and in vivo photodamage. TO-F10 increased the viability of UVB-irradiated human keratinocytes via suppressing apoptosis by reducing the intracellular ROS level. Besides, TO-F10 effectively attenuated in vivo photodamage stimulated by UVB irradiation via inhibiting oxidative stress and inflammatory response in zebrafish. These results demonstrate that TO-F10 possesses in vitro and in vivo antioxidant and photoprotective effects, and suggest TO-F10 is a potential ingredient in the cosmetic industry.
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Antioxidantes , Phaeophyceae , Animales , Chlorocebus aethiops , Humanos , Antioxidantes/farmacología , Antioxidantes/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Pez Cebra/metabolismo , Células Vero , Estrés Oxidativo , Queratinocitos , Phaeophyceae/metabolismo , Rayos UltravioletaRESUMEN
This study evaluated the efficacy of Monascus purpureus fermentation on Saccharina japonica (SJ). Healthy substances and antioxidant activity of fermented SJ (FSJ) were determined. Results showed that fermentation caused the release of phenolic compounds and flavonoids, which resulted in the enhancement of antioxidant activity. Essential amino acids and γ-aminobutyric acid also greatly accumulated in FSJ. Sensory evaluation and gas chromatography-ion mobility spectrometry (GC-IMS) were used to evaluate flavor properties of FSJ. A lexicon consisted of 24 descriptors was established for SJ and FSJ, of which 14 descriptors were regarded as odor attributes. A total of 46 volatile compounds were identified by GC-IMS and showed positive correlation with odor attributes. Fifteen volatile compounds were screened as key compounds, tricarboxylic acid cycle, embden-meyerhof-parnas and amino acid catabolism were main formation metabolisms of them. Advanced properties of FSJ indicated that fermentation is a promising approach for the production of SJ food.
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Kelp , Laminaria , Monascus , Compuestos Orgánicos Volátiles , Aminoácidos/metabolismo , Aminoácidos Esenciales/metabolismo , Antioxidantes/análisis , Fermentación , Flavonoides/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Laminaria/metabolismo , Monascus/metabolismo , Compuestos Orgánicos Volátiles/análisis , Ácido gamma-Aminobutírico/análisisRESUMEN
G protein-coupled receptors (GPCRs) represent promising therapeutic targets due to their involvement in numerous physiological processes mediated by downstream G protein- and ß-arrestin-mediated signal transduction cascades. Although the precise control of GPCR signaling pathways is therapeutically valuable, the molecular details for governing biased GPCR signaling remain elusive. The Angiotensin II type 1 receptor (AT1R), a prototypical class A GPCR with profound implications for cardiovascular functions, has become a focal point for biased ligand-based clinical interventions. Herein, we used single-molecule live-cell imaging techniques to evaluate the changes in stoichiometry and dynamics of AT1R with distinct biased ligand stimulations in real time. It was revealed that AT1R existed predominantly in monomers and dimers and underwent oligomerization upon ligand stimulation. Notably, ß-arrestin-biased ligands induced the formation of higher-order aggregates, resulting in a slower diffusion profile for AT1R compared to G protein-biased ligands. Furthermore, we demonstrated that the augmented aggregation of AT1R, triggered by activation from each biased ligand, was completely abrogated in ß-arrestin knockout cells. These findings furnish novel insights into the intricate relationship between GPCR aggregation states and biased signaling, underscoring the pivotal role of molecular behaviors in guiding the development of selective therapeutic agents.
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Receptor de Angiotensina Tipo 1 , Imagen Individual de Molécula , Ligandos , Transducción de Señal , beta-Arrestina 1 , Proteínas de Unión al GTPRESUMEN
Breast cancer is the second highest incidence of cancer in the world. It is of great significance to find biomarkers to diagnose breast cancer and predict the prognosis of breast cancer patients. PAIP2 is a poly (A) -binding protein interacting protein that regulates the expression of VEGF. However, the possible role of PAIP2 in the progression of breast cancer is still unknown. RT-qRCR and Western blotting were used to verify the expression of PAIP2 in breast cancer cells and normal breast cells. The data of breast cancer samples were obtained in the TCGA database and the HPA database to analyze the expression of PAIP2 in breast cancer samples. Transwell experiment and CCK8 experiment confirmed the changes in the invasion and proliferation ability of PAIP2 after siRNA was down-regulated. Using bioinformatics technology to explore the prognostic value of PAIP2 and its possible biological function, and its effect on tumor immunity and immunotherapy. Studies have shown that PAIP2 has higher expression in breast cancer tissues and breast cancer cells. PAIP2 can promote the proliferation and invasion of breast cancer cells and has significantly high expression in higher tumor stages. The high expression of PAIP2 is associated with better OS in breast cancer patients and is negatively correlated with most chemotherapeutic drug sensitivity and IPS in cancer immunotherapy. Our study explored the potential value of PAIP2 as a biomarker for diagnosis and prognosis and may predict the efficacy of immunotherapy, providing reference for the follow-up study on the role of PAIP2 in breast cancer.
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Fucoidans possess potent anti-inflammatory effects. In the present study, the anti-inflammatory effect of the fucoidan (SFF-PS-F5) isolated from fermented Sargassum fusiforme was evaluated in vitro in RAW 264.7 macrophages and in vivo in zebrafish. The in vitro test results demonstrate that SFF-PS-F5 effectively inhibited nitric oxide (NO) production induced by lipopolysaccharides (LPS) in RAW 264.7 cells. SFF-PS-F5 effectively and concentration-dependently improved the viability of LPS-stimulated RAW 264.7 cells, and reduced the level of prostaglandin E2, interleukin-1 beta, tumor necrosis factor-alpha, and interleukin-6. Further results display that these effects were actioned by suppressing the expression of inducible nitric oxide synthase and cyclooxygenase-2 via regulating the nuclear factor kappa-B signaling pathway. The in vivo test results indicate that SFF-PS-F5 remarkably reduced reactive oxygen species, cell death, and NO levels in LPS-treated zebrafish. These results indicate that SFF-PS-F5 could inhibit both in vitro and in vivo inflammatory responses and suggest it is a functional ingredient in the functional food and cosmetic industries.
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Sargassum , Ratones , Animales , Sargassum/metabolismo , Lipopolisacáridos/farmacología , Pez Cebra/metabolismo , Antiinflamatorios/farmacología , Óxido Nítrico Sintasa de Tipo II/metabolismo , FN-kappa B/metabolismo , Células RAW 264.7 , Ciclooxigenasa 2/metabolismo , Óxido Nítrico/metabolismoRESUMEN
Seaweeds are potential ingredients in the cosmeceutical industry. Our previous study demonstrates that the phlorotannin-enriched extract of Ecklonia maxima (EME-EA) containing dieckol and eckmaxol possesses strong anti-inflammatory activity and suggests the cosmeceutical potential of EME-EA. In order to evaluate the cosmeceutical potential of EME-EA, the anti-melanogenesis and photoprotective effects of EME-EA were investigated in this study. EME-EA remarkably inhibited mushroom tyrosinase and melanogenesis in alpha-melanocyte-stimulating hormone-stimulated B16F10 cells. In addition, EME-EA significantly suppressed UVB-induced HaCaT cell death that was consistent with inhibition of apoptosis and reduction in scavenging intracellular reactive oxygen species. Furthermore, EME-EA significantly inhibited collagen degradation and matrix metalloproteinases expression in UVB-irradiated HDF cells in a concentration-dependent manner. These results indicate that EME-EA possesses strong anti-melanogenesis and photoprotective activities and suggest EME-EA is an ideal ingredient in the pharmaceutical and cosmeceutical industries.
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Cosmecéuticos , Phaeophyceae , Antiinflamatorios , Benzofuranos , Colágeno/metabolismo , Metaloproteinasas de la Matriz , Melaninas , Monofenol Monooxigenasa/metabolismo , Phaeophyceae/metabolismo , Especies Reactivas de Oxígeno , alfa-MSH/farmacologíaRESUMEN
In this study, the anti-inflammatory activity of sulfated polysaccharides isolated from the green seaweed Codium fragile (CFCE-PS) was investigated in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and zebrafish. The results demonstrated that CFCE-PS significantly increased the viability of LPS-induced RAW 264.7 cells in a concentration-dependent manner. CFCE-PS remarkably and concentration-dependently reduced the levels of inflammatory molecules including prostaglandin E2, nitric oxide (NO), interleukin-1 beta, tumor necrosis factor-alpha, and interleukin-6 in LPS-stimulated RAW 264.7 cells. In addition, in vivo test results indicated that CFCE-PS effectively reduced reactive oxygen species, cell death, and NO levels in LPS-stimulated zebrafish. Thus, these results indicate that CFCE-PS possesses in vitro and in vivo anti-inflammatory activities and suggest it is a potential ingredient in the functional food and pharmaceutical industries.
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Chlorophyta , Lipopolisacáridos , Animales , Antiinflamatorios/farmacología , Chlorophyta/metabolismo , Lipopolisacáridos/farmacología , Macrófagos , Ratones , FN-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Polisacáridos/farmacología , Células RAW 264.7 , Sulfatos/farmacología , Pez Cebra/metabolismoRESUMEN
Based on Mindlin's first-order plate theory, the high-frequency vibrations of piezoelectric bulk acoustic wave array sensors under lateral-field-excitation based on crystals with 3 m point group are analyzed, and the spectral-frequency relationships are solved, based on which, the optimal length-thickness ratio of the piezoelectric crystal plate is determined. Then, the dynamic capacitance diagram is obtained by a forced vibration analysis of the piezoelectric crystal plate. The resonant mode conforming to good energy trapping is further obtained. The frequency interferences between different resonator units are calculated, and the influences of the spacing between two resonant units on the frequency interference with different electrode widths and spacings are analyzed. Finally, the safe spacings between resonator units are obtained. As the electrode spacing value of the left unit increases, the safe spacing d0 between the two resonator units decreases, and the frequency interference curve tends to zero faster. When the electrode spacings of two resonator units are equal, the safe distance is largest, and the frequency interference curve tends to zero slowest. The theoretical results are verified further by finite element method. The analysis model of high frequency vibrations of strongly coupled piezoelectric bulk acoustic array device based on LiTaO3 crystals with 3 m point group proposed in this paper can provide reliable theoretical guidance for size optimization designs of strongly coupled piezoelectric array sensors under lateral-field-excitation.
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In this study, a fucoidan (SFF-PS-F5) with a molecular weight of 213.33 kDa was isolated from fermented Sargassum fusiforme and the antioxidant activity of SFF-PS-F5 was investigated in vitro in Vero cells and in vivo in zebrafish. SFF-PS-F5 contains 91.68% of fucoidan (72.06% of carbohydrate and 19.62% of sulfate content). SFF-PS-F5 protected hydrogen peroxide (H2O2)-stimulated Vero cells damage by suppressing apoptosis via scavenging intracellular reactive oxygen species (ROS) by up-regulating the intracellular antioxidants. Further results indicated that these actions worked by elevating Nrf2 levels. The in vivo test results displayed that SFF-PS-F5 improved the survival rate by attenuating cell death via suppressing lipid peroxidation by scavenging ROS in H2O2-stimulated zebrafish. These results indicated that SFF-PS-F5 isolated from S. fusiforme possesses potent in vitro and in vivo antioxidant effects and it is a potential ingredient in pharmaceutical, nutraceutical, and cosmeceutical industries.
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Sargassum , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Catalasa/metabolismo , Chlorocebus aethiops , Peróxido de Hidrógeno/farmacología , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo , Polisacáridos/farmacología , Especies Reactivas de Oxígeno/metabolismo , Sargassum/metabolismo , Transducción de Señal , Células Vero , Pez Cebra/metabolismoRESUMEN
Low-cost transition-metal chalcogenides (MSx ) are demonstrated to be potential candidate cocatalyst for photocatalytic H2 generation. However, their H2 -generation performance is limited by insufficient quantities of exposed sulfur (S) sites and their strong bonding with adsorbed hydrogen atoms (SHads ). To address these issues, an efficient coupling strategy of active-site-enriched regulation and electronic structure modification of active S sites is developed by rational design of core-shell Au@NiS1+ x nanostructured cocatalyst. In this case, the Au@NiS1+ x cocatalyst can be skillfully fabricated to synthesize the Au@NiS1+ x modified TiO2 (denoted as TiO2 /Au@NiS1+ x ) by a two-step route. Photocatalytic experiments exhibit that the resulting TiO2 /Au@NiS1+ x (1.7:1.3) displays a boosted H2 -generation rate of 9616 µmol h-1 g-1 with an apparent quantum efficiency of 46.0% at 365 nm, which is 2.9 and 1.7 times the rate over TiO2 /NiS1+ x and TiO2 /Au, respectively. In situ/ex situ XPS characterization and density functional theory calculations reveal that the free-electrons of Au can transfer to sulfur-enriched NiS1+ x to induce the generation of electron-enriched Sδ - active centers, which boosts the desorption of Hads for rapid hydrogen formation via weakening the strong SHads bonds. Hence, an electron-enriched Sδ - -mediated mechanism is proposed. This work delivers a universal strategy for simultaneously increasing the active site number and optimizing the binding strength between the active sites and hydrogen adsorbates.