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1.
Langmuir ; 40(24): 12778-12791, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38843811

RESUMO

In this work, cobalt-doped oxygen-vacancies-rich BiVO4 (Co/BiVO4-Vo) was successfully synthesized for the degradation of tetracycline (TC) by activated peroxymonosulfate (PMS) under visible light. The morphologies, microstructures, and optical properties of the photocatalysts were analyzed in detail. Co/BiVO4-Vo exhibited significantly enhanced degradation, removing 92.3% of TC within 10 min, which was greater than those of pure BiVO4 (62.2%) and oxygen-vacancies-rich BiVO4 (BiVO4-Vo) (72.0%), respectively. The photogenerated charge separation and transport properties were explored through surface photovoltage (SPV), photoluminescence spectrum (PL), and UV-vis diffuse reflectance spectroscopy (UV-vis DRS) measurements. Additionally, an in-depth investigation was conducted on the photocatalytically assisted advanced oxidation processes based on SO4•- (SR-AOPs) for the degradation of organic pollutants. The experimental results showed that the introduction of oxygen vacancies and Co doping achieved an effective separation of photogenerated carriers, which could accelerate the cycling between Co3+ and Co2+ and further activate PMS. The results of free radical capture experiments and electron spin resonance (ESR) experiments showed that reactive oxygen species (ROSs) such as 1O2, •O2-, and SO4•- played a dominant role in the removal of pollutants. This work provides a novel insight into the further development of efficient and rapid PMS photoactivators for environmental remediation of water bodies.

2.
Nanotechnology ; 34(23)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36863007

RESUMO

Y-doping can effectively improve the performance of HfOx-based resistive random-access memory (RRAM) devices, but the underlying physical mechanism of Y-doping affecting the performance of HfOx-based memristors is still missing and unclear. Although impedance spectroscopy (IS) has been widely used to investigate impedance characteristics and switching mechanisms of RRAM devices, there is less IS analysis on Y-doped HfOx-based RRAM devices as well as devices at different temperatures. Here, the effect of Y-doping on the switching mechanism of HfOx-based RRAM devices with a Ti/HfOx/Pt structure were reported using current-voltage characteristics and IS. The results indicated that doping Y into HfOxfilms could decrease the forming/operate voltage and improve the RS uniform. Both doped and undoped HfOx-based RRAM devices obeyed the oxygen vacancies (VO) conductive filament model along the grain boundary (GB). Additionally, the GB resistive activation energy of the Y-doped device was inferior to that of the undoped device. It exhibited a shift of theVOtrap level towards the conduction band bottom after Y-doping in the HfOxfilm, which was the main reason for the improved RS performance.

3.
Sensors (Basel) ; 23(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37447916

RESUMO

Linear active disturbance rejection control (LADRC) has been widely used to improve the tracking accuracy and anti-disturbance performance of telescope servo control under disturbances. However, the linear extended state observer (LESO) is sensitive to noise, and its bandwidth is limited by the resonant frequency of the telescope. To enhance the LARDC's ability to attenuate disturbances, a novel cascade anti-disturbance structure (NCADS) with LADRC on the outer speed loop and a nonlinear disturbance observer (NDOB) on the inner current loop is proposed. The NDOB compensates for the dominant disturbance through feedforwarding the q-axis current reference, and the LESO compensates for the residual disturbance on the outer speed loop. First, the NCADS is introduced in a three-closed-loop control framework of PMSM. Then, the design method of the controller for each loop and the NDOB are presented, the parameter-tuning method based on bandwidth is demonstrated, and the convergence of the NDOB is proved. Furthermore, to improve the searching and tracking efficiency of wide-field survey telescopes, the nonlinear tracking differentiator (NTD) was modified to plan the transition process of the position loop, which only needs to set the maximum speed and acceleration of the telescope. Finally, simulations and experiments were performed on a 2.5-m-wide field survey telescope. The experimental results verify that the proposed NCADS method has a better anti-disturbance performance and higher tracking precision than the conventional method, and the improved NTD method does not need to tune parameters and achieved a fast and smooth transition process of the position loop.


Assuntos
Telescópios , Projetos de Pesquisa , Aceleração
4.
Sensors (Basel) ; 22(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36298432

RESUMO

The high demand for pressure devices with miniaturization and a wide bearing range has encouraged researchers to explore new high-performance sensors from different approaches. In this study, a sensitive element based on graphene in-plane compression properties for realizing pressure sensing is experimentally prepared using microelectromechanical systems (MEMS) fabrication technology; it consists of a 50 µm thick, 1400 µm wide square multilayer component membrane and a graphene monolayer with a meander pattern. The prepared sample is extensively characterized and analyzed by using various techniques, including atomic force microscopy, Raman spectroscopy, infrared spectroscopy, X-ray photoelectron spectroscopy, COMSOL finite element method, and density functional theory. The sensing performance of the new pressure sensor based on the sensitive element are obtained by theoretical analysis for electromechanical measurements of the sensitive element before and after low-temperature annealing in atmosphere. Results demonstrate that atmospheric annealing at 300 °C enhances the pressure sensing sensitivity by 4 times compared to pristine graphene without annealing, which benefits from the desorption of hydroxyl groups on the graphene surface during annealing. The sensitivity is comparable and even better than that of previous sensors based on graphene in-plane properties. Our results provide new insights into realizing high-performance MEMS devices based on 2D sensitive materials.

5.
Langmuir ; 37(24): 7617-7624, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34115506

RESUMO

A series of Al-doped BiVO4 composites have been synthesized via the hydrothermal method for methylene blue (MB) degradation application. The reasons for the improvement of photocatalytic performance was explained from the perspective of optics. Transient photovoltage (TPV) measurements suggested that the surface states have the priority to capture photogenerated carriers, and the Al2O3 surface passivation layer can prolong the lifetime of charge carrier. The results of surface photovoltage (SPV), transient photovoltage (TPV), and surface photocurrent (SPC) measurements suggested that the coexistence of Al3+ and Al2O3 caused by the appropriate doping would improve the transfer property and prolong the lifetime of photogenerated carriers. Finally, the possible photocatalytic mechanism is expounded to illustrate the photogenerated charge behavior under visible light irradiation. This work provides a better understanding of the synergistic effect of Al-doping and Al2O3 passivation layer on enhancing the photocatalytic performance.

6.
Ecotoxicol Environ Saf ; 208: 111467, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33080422

RESUMO

Five currently used novel brominated flame retardants (NBFRs) were determined in 172 serum samples collected from nonoccupational residents of a major BFR-producing region. All the 5 NBFRs presented high detection frequencies (DFs, >90%), and decabromodiphenyl ethane (DBDPE), a substitute of decabrominated diphenyl ethers (deca-BDE), was the most abundant NBFR. The levels of DBDPE were from

Assuntos
Poluentes Ambientais/sangue , Retardadores de Chama/metabolismo , Éteres Difenil Halogenados/sangue , Biomarcadores , Criança , Monitoramento Ambiental/métodos , Feminino , Retardadores de Chama/análise , Éteres Difenil Halogenados/análise , Halogenação , Humanos , Fígado/química , Glândula Tireoide/química
7.
Anal Chem ; 92(21): 14536-14541, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33073993

RESUMO

The wearable and integrated sensing platform is a promising choice for developing real-time analytic electronics with clear advantages but still poses challenges, such as the realization of high precision, low limit of detection (LOD), moderate mechanical capacity, integration, and miniaturization. In this work, a simple printed wearable smartsensor has been fabricated with the aid of electrochemical plating methods with bismuth (Bi) films. The excellent sensing behaviors, including linear relationship, selectivity, stability, repeatability, and the LOD at ppb levels, have been obtained by this smartsensor. Additionally, the highly flexible textile-based sensor exhibits potential application on the substrates of daily cloth, sports T-shirt, and sports wristbands, and it maintains good stability under repeated deformations of washing and twisting. Importantly, integrated with printed circuit board, single chip micyoco, and Bluetooth modules, a smartsensing platform is successfully acquired for real-time detection of heavy metals (e.g., Zn, Cd, Pb, etc.). Finally, actual samples of human sweat, seawater, cosmetics, and drinking water have been remotely successfully demonstrated for detection by this smartsensor, enabling a great promise for fast on-site screening of samples in practical application.


Assuntos
Atenção à Saúde , Metais Pesados/análise , Dispositivos Eletrônicos Vestíveis , Humanos , Limite de Detecção , Suor/química , Têxteis , Fatores de Tempo
8.
J Cell Biochem ; 120(3): 3861-3873, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30304552

RESUMO

BACKGROUND: Smilax glabra Roxb, a traditional Chinese herb, has been widely used in folk medicine. The current study was performed to investigate the protective effect of S. glabra Roxb extract, pure total flavonoids from Smilax glabra Roxb (PTFS), on renal interstitial fibrosis (RIF) and its underlying mechanism. METHODS: First, a surgical model of unilateral ureteral obstruction was established in rats to induce RIF. Then, rats were grouped and treated with PTFS at different concentration. Second, HK-2 cells underwent an epithelial-mesenchymal transition (EMT) by the addition of transforming growth factor-ß1 (TGF-ß1). Additionally, HK-2 cells after inducing for EMT were transfected with microRNA-21 (miR-21) mimic or inhibitor. These HK-2 cells were grouped and treated with PTFS at different concentration. Finally, real-time polymerase chain reaction and Western blot analysis were performed to detect the expression of possible signaling factor involved in RIF in renal tissues or HK-2 cells after PTFS treatment. RESULTS: In vivo and in vitro experiments indicated that PTFS treatment could decrease the expression of α-smooth muscle actin (α-SMA; mesenchymal marker) and increase the expression of E-cadherin (epithelial marker) in both messenger RNA and protein level. Moreover, PTFS also attenuated the expression of TGF-ß1/Smad signaling in both renal tissues and HK-2 cells that underwent EMT. Overexpression or inhibition of miR-21 in HK-2 cells activated or blocked the PI3K/Akt signaling via targeting phosphatase and tension homolog (PTEN), and then promoted or suppressed the progress of TGF-ß1-induced EMT by regulating the expression of α-SMA and E-cadherin. Furthermore, PTFS treatment inhibited TGF-ß1-induced EMT progress by blocking miR-21/PTEN/PI3K/Akt signaling. CONCLUSION: PTFS has strong anti-EMT and antifibrosis effects both in vitro and in vivo. The mechanism underlying these effects may be related to inhibition of TGF-ß1/Smad, and their downstream miR-21/PTEN signaling, leading to blocks of EMT process during RIF.


Assuntos
Transição Epitelial-Mesenquimal/efeitos dos fármacos , Flavonoides/farmacologia , MicroRNAs/genética , PTEN Fosfo-Hidrolase/genética , Substâncias Protetoras/farmacologia , Smilax/química , Obstrução Ureteral/tratamento farmacológico , Actinas/genética , Actinas/metabolismo , Animais , Antagomirs/genética , Antagomirs/metabolismo , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular Transformada , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal/genética , Fibrose/prevenção & controle , Flavonoides/isolamento & purificação , Regulação da Expressão Gênica , Humanos , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/patologia , Masculino , MicroRNAs/agonistas , MicroRNAs/antagonistas & inibidores , MicroRNAs/metabolismo , Oligorribonucleotídeos/genética , Oligorribonucleotídeos/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Substâncias Protetoras/isolamento & purificação , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Proteínas Smad/genética , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Obstrução Ureteral/genética , Obstrução Ureteral/metabolismo , Obstrução Ureteral/patologia
9.
Plant Biotechnol J ; 16(4): 844-855, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28905515

RESUMO

The clustered regularly interspaced short palindromic repeats-associated protein 9 (CRISPR/Cas9) system is a powerful tool for editing plant genomes. Efficient genome editing of grape (Vitis vinifera) suspension cells using the type II CRISPR/Cas9 system has been demonstrated; however, it has not been established whether this system can be applied to get biallelic mutations in the first generation of grape. In this current study, we designed four guide RNAs for the VvWRKY52 transcription factor gene for using with the CRISPR/Cas9 system, and obtained transgenic plants via Agrobacterium-mediated transformation, using somatic embryos of the Thompson Seedless cultivar. Analysis of the first-generation transgenic plants verified 22 mutant plants of the 72 T-DNA-inserted plants. Of these, 15 lines carried biallelic mutations and seven were heterozygous. A range of RNA-guided editing events, including large deletions, were found in the mutant plants, while smaller deletions comprised the majority of the detected mutations. Sequencing of potential off-target sites for all four targets revealed no off-target events. In addition, knockout of VvWRKY52 in grape increased the resistance to Botrytis cinerea. We conclude that the CRISPR/Cas9 system allows precise genome editing in the first generation of grape and represents a useful tool for gene functional analysis and grape molecular breeding.


Assuntos
Sistemas CRISPR-Cas , Melhoramento Vegetal/métodos , Plantas Geneticamente Modificadas , Vitis/genética , Botrytis/patogenicidade , Resistência à Doença/genética , Edição de Genes , Técnicas de Inativação de Genes , Vetores Genéticos , Homozigoto , Mutagênese , Mutagênese Sítio-Dirigida , Mutação , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Vitis/microbiologia
10.
J Am Chem Soc ; 139(36): 12370-12373, 2017 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-28686430

RESUMO

Developing nonprecious hydrogen evolution electrocatalysts that can work well at large current densities (e.g., at 1000 mA/cm2: a value that is relevant for practical, large-scale applications) is of great importance for realizing a viable water-splitting technology. Herein we present a combined theoretical and experimental study that leads to the identification of α-phase molybdenum diboride (α-MoB2) comprising borophene subunits as a noble metal-free, superefficient electrocatalyst for the hydrogen evolution reaction (HER). Our theoretical finding indicates, unlike the surfaces of Pt- and MoS2-based catalysts, those of α-MoB2 can maintain high catalytic activity for HER even at very high hydrogen coverage and attain a high density of efficient catalytic active sites. Experiments confirm α-MoB2 can deliver large current densities in the order of 1000 mA/cm2, and also has excellent catalytic stability during HER. The theoretical and experimental results show α-MoB2's catalytic activity, especially at large current densities, is due to its high conductivity, large density of efficient catalytic active sites and good mass transport property.

11.
Phys Chem Chem Phys ; 19(24): 15724-15733, 2017 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-28597886

RESUMO

Anatase TiO2 nanowire (NW) films modified with inverted type-I CdS/CdSe core/shell structure QDs have been successfully prepared by the post synthesis ligand-assisted technique. Surface photovoltage (SPV), transient photovoltage (TPV) and transient photocurrent (TPC) measurements demonstrate that CdS/CdSe core/shell structure QD-sensitized TiO2 NWs electrodes favor photoexicited electron injection and charge transfer due to the special photo-electronic features of CdS/CdSe core/shell structure QDs. With a polysulfide electrolyte, the maximum conversion efficiency was 2.18% for CdS/CdSe QDs with the CdSe shell being 4.4 nanometers thick; a PCE of 0.07% for CdS QDs and a PCE of 0.63% for CdSe QDs were obtained under illumination at 100 mW cm-2. The results reveal that the CdS/CdSe core/shell structure QDs sensitized TiO2 NW electrodes have promising applications in solar cells.

12.
J Sep Sci ; 40(3): 709-716, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27885791

RESUMO

Two simplified sample preparation procedures for simultaneous extraction and clean-up of tetrabromobisphenol A, α-, ß-, and γ-hexabromocyclododecane and polybrominated diphenyl ethers in human serum were developed and validated. The first procedure was based on solid-phase extraction. Sample extraction, purification, and lipid removal were carried out directly on an Oasis HLB cartridge. The second procedure was a quick, easy, cheap, effective, rugged, and safe-based approach using octadecyl-modified silica particles as a sorbent. After sample extraction and cleanup, tetrabromobisphenol A/hexabromocyclododecane was separated from polybrominated diphenyl ethers by using a Si-based cartridge. Tetrabromobisphenol A and hexabromocyclododecane were then detected by high-performance liquid chromatography coupled to tandem mass spectrometry, while polybrominated diphenyl ethers were detected by gas chromatography coupled to tandem mass spectrometry. The results of the spike recovery test using fetal bovine serum showed that the average recoveries of the analytes ranged from 87.3 to 115.3% with relative standard deviations equal to or lower than 13.4 %. Limits of detection of the analytes were in the range of 0.4-19 pg/mL except for decabromodiphenyl ether. The developed method was successfully applied to routine analysis of human serum samples from occupational workers and the general population. Extremely high serum polybrominated diphenyl ethers levels up to 3.32 × 104 ng/g lipid weight were found in occupational workers.


Assuntos
Análise Química do Sangue/métodos , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos/sangue , Espectrometria de Massas em Tandem , Poluentes Ambientais/sangue , Éteres Difenil Halogenados/sangue , Humanos , Hidrocarbonetos Bromados/sangue , Limite de Detecção , Exposição Ocupacional , Bifenil Polibromatos/sangue , Extração em Fase Sólida
13.
Int J Mol Sci ; 18(9)2017 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-28926983

RESUMO

Stilbene synthase (STS) is a key enzyme that catalyzes the biosynthesis of resveratrol compounds and plays an important role in disease resistance. The molecular pathways linking STS with pathogen responses and their regulation are not known. We isolated an STS gene, VaSTS19, from a Chinese wild grape, Vitis amurensis Rupr. cv. "Tonghua-3", and transferred this gene to Arabidopsis. We then generated VaSTS19-expressing Arabidopsis lines and evaluated the functions of VaSTS19 in various pathogen stresses, including powdery mildew, B. cinerea and Pseudomonas syringae pv. tomato DC3000 (PstDC3000). VaSTS19 enhanced resistance to powdery mildew and B. cinerea, but increased susceptibility to PstDC3000. Aniline blue staining revealed that VaSTS19 transgenic lines accumulated more callose compared to nontransgenic control plants, and showed smaller stomatal apertures when exposed to pathogen-associated molecular patterns (flagellin fragment (flg22) or lipopolysaccharides (LPS)). Analysis of the expression of several disease-related genes suggested that VaSTS19 expression enhanced defense responses though salicylic acid (SA) and/or jasmonic acid (JA) signaling pathways. These findings provide a deeper insight into the function of STS genes in defense against pathogens, and a better understanding of the regulatory cross talk between SA and JA pathways.


Assuntos
Aciltransferases/genética , Arabidopsis/genética , Resistência à Doença/genética , Proteínas de Plantas/genética , Aciltransferases/metabolismo , Arabidopsis/imunologia , Arabidopsis/microbiologia , Botrytis/patogenicidade , Proteínas de Plantas/metabolismo , Pseudomonas/patogenicidade , Vitis/genética
14.
Phys Chem Chem Phys ; 18(46): 31534-31541, 2016 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-27831573

RESUMO

Nickel, a non-noble metal, is one of the most promising candidates for photocatalysis because it is inexpensive and an earth-abundant metal. Herein, Ni/CM-C3N4 nanocomposites with Ni as a cocatalyst were synthesized by a simple solvothermal method. Field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) confirmed that Ni nanoparticles were loaded onto the surface of CM-C3N4. The prepared Ni/CM-C3N4 nanocomposites exhibited an enhanced hydrogen evolution activity. The most active catalyst contained 10% Ni and produced H2 at a rate of 313.2 µmol h-1 g-1, which was obviously higher than that of pure CM-C3N4. The results of photoluminescence (PL) and photoacoustics (PA) studies indicated that the recombination efficiency of photo-induced electron-hole pairs was decreased for CM-Ni10 as compared to that for unmodified CM-C3N4. The transient photovoltage (TPV) measurements directly demonstrated that the recombination time of electron-hole pairs in CM-Ni10 was prolonged. More importantly, the reversed surface photovoltage (SPV) and the declined surface photocurrent (SPC) response of CM-Ni10 revealed that the photogenerated electrons could be trapped by Ni, leading to a better separation efficiency and a superior hydrogen production. Finally, the possible mechanism is proposed to illuminate the photogenerated charge behavior between CM-C3N4 and Ni, which might provide a theoretical basis to develop efficient cocatalysts for photocatalytic water splitting.

15.
Exp Cell Res ; 338(2): 232-8, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26297956

RESUMO

MiR-145 is downregulated and functions as a tumor suppressor in many malignancies. In this study, the biological function, molecular mechanism, and direct target genes of miR-145 in nasopharyngeal carcinoma (NPC) cells were investigated. Cell survival was detected by cell viability assay, and cell cycle was determined through flow cytometry. Invasion and migration of NPC cells were examined using cell invasion and wound healing assays, respectively. A disintegrin and metalloproteinase 17 (ADAM17) was verified as the target of miR-145 through luciferase reporter assay, qRT-PCR, and Western blot analysis. In NPC cell lines, miR-145 expression was significantly downregulated and ADAM17 protein expression was upregulated. ADAM17 was downregulated at the post-transcriptional level by miR-145 via the binding site of ADAM17-3'UTR. Transfection with miR-145 mimic suppressed cell growth and induced cell cycle arrest in the G0/G1 phase by upregulating key G0/G1 phase regulators, namely, p53 and p21. MiR-145 also inhibited cellular migration and invasion through targeting ADAM17 involving the regulation of EGFR and E-cadherin. Knockdown of ADAM17 elicited similar effects to that of miR-145 on NPC cells. This study reveals that miR-145 suppressed the invasion and migration of NPC cells by targeting ADAM17. Thus, miR-145 could be a therapeutic target for NPC.


Assuntos
Proteínas ADAM/genética , Movimento Celular/genética , MicroRNAs/genética , Neoplasias Nasofaríngeas/genética , Invasividade Neoplásica/genética , Regiões 3' não Traduzidas/genética , Proteína ADAM17 , Caderinas/genética , Carcinoma , Linhagem Celular Tumoral , Regulação para Baixo/genética , Receptores ErbB/genética , Pontos de Checagem da Fase G1 do Ciclo Celular/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/patologia , Invasividade Neoplásica/patologia , Processamento Pós-Transcricional do RNA/genética , Fase de Repouso do Ciclo Celular/genética , Regulação para Cima/genética
16.
Zhongguo Zhong Yao Za Zhi ; 41(4): 711-715, 2016 Feb.
Artigo em Zh | MEDLINE | ID: mdl-28871698

RESUMO

To explore the effect of total flavones from hawthorn leaf on (THFL) on the expression of COX-2/Nrf2 in the liver tissues of rats with nonalcoholic steatohepatitis (NASH), and discuss its anti-NASH mechanism, thirty-two SD rats were randomly divided into the normal group, model group, THFL high dose group and low dose group, 8 in each group. High fat diet was given to the rats for 12 weeks to establish the NASH models, and the high and low dose groups were administered with TFHL at the dosage of 250, 125 mg•kg⁻¹â€¢d⁻¹ respectively. Steatosis and the inflammatory changes of the liver tissues in rats were observed by HE staining; T-AOC level was detected by colorimetry; the level of 8-OHdG and the protein expressions of COX-2, Nrf2 and HO-1 in the liver tissues were determined by immunohistochemistry; and the mRNA expressions of COX-2, Nrf2 and HO-1 in liver tissues were detected by Real time-PCR. Compared with the normal group, the liver steatosis, ballooning degeneration for inflammatory degree and NAFLD activity scores (NAS) were significantly increased in model group, while total antioxidant capacity (T-AOC) was decreased, DNA damage marker 8-OHdG level was increased, and the mRNA and protein expressions of COX-2, Nrf2 and HO-1 were significantly increased. After the administration of high and low dose of TFHL, the inflammation degree of the liver tissues and NAS were significantly decreased, 8-OHdG level and COX-2mRNA and protein expressions were decreased, and the mRNA and protein expressions of Nrf2 and HO-1 were significantly increased when compared with the model group. COX-2/Nrf2 pathway was involved in the development and progression of NASH induced by high fat diet. TFHL could prevent the development of NASH by promoting the expression Nrf2/HO-1, regulating and inhibiting the over expression of COX-2, and further attenuating the cell injury and hepatic inflammation caused by oxidation reaction.


Assuntos
Crataegus/química , Ciclo-Oxigenase 2/genética , Medicamentos de Ervas Chinesas/administração & dosagem , Flavonas/administração & dosagem , Fator 2 Relacionado a NF-E2/genética , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Animais , Ciclo-Oxigenase 2/metabolismo , Dieta Hiperlipídica/efeitos adversos , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Fator 2 Relacionado a NF-E2/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Ratos , Ratos Sprague-Dawley
17.
Angew Chem Int Ed Engl ; 55(38): 11442-6, 2016 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-27529769

RESUMO

A facile synthetic route is presented that produces a porous Ga-In bimetallic oxide nanophotocatalyst with atomically thin pore walls. The material has an unprecedented electronic structure arising from its ultrathin walls. The bottom of the conduction band and the top of the valence band of the material are distributed on two opposite surfaces separated with a small electrostatic potential difference. This not only shortens the distance by which the photogenerated charges travel from the sites where they are generated to the sites where they catalyze the reactions, but also facilitates charge separations in the material. The porous structure within the walls results in a large density of exposed surface reactive/catalytic sites. Because of these optimized electronic and surface structures, the material exhibits superior photocatalytic activity toward the hydrogen evolution reaction (HER).

18.
Nutr Cancer ; 67(7): 1151-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26359675

RESUMO

Epidemiological and experimental evidence supports the key role of diet in the development of many types of cancer. Recent studies have suggested that dietary modifications may be beneficial for individuals at high risk for hepatocellular carcinoma (HCC). In this study, we investigated the effect of a high-protein (HP; 20% casein) dietondiethylnitrosamine (DEN)-induced hepatocarcinogenesis. Mice were given free access to water with 30 µg/ml DEN and fed a normal or HP diet for 22 wk. The results showed mice consuming HP diets had reduced mortality rates and body weights and lower hepatic enzyme activity compared to DEN-treated mice on a normal diet. HP consumption also promoted collagen accumulation in the liver, and reduced numbers of proliferating hepatocytes and infiltrating inflammatory cells, as well as decreased expression of inflammatory factor interleukin-1ß, and nuclear factor κB activation. These data indicate that HP diets can inhibit DEN-induced hepatocarcinogenesis via suppression of the inflammatory response and provide a new evidence for the dietary management of clinical patients with hepatocellular carcinoma.


Assuntos
Proteínas Alimentares/farmacologia , Dietilnitrosamina/toxicidade , Neoplasias Hepáticas Experimentais/dietoterapia , Animais , Caseínas/farmacologia , Proliferação de Células/efeitos dos fármacos , Colágeno/metabolismo , Proteínas Alimentares/química , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Interleucina-1beta/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/mortalidade , Neoplasias Hepáticas Experimentais/patologia , Masculino , Camundongos Endogâmicos C3H , NF-kappa B/metabolismo , Taxa de Sobrevida
19.
Phys Chem Chem Phys ; 17(46): 31316-23, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26551930

RESUMO

Three dimensional (3D) center-hollow ZnO architectures assembled by nanoparticles have been successfully fabricated on a large scale via a template-free method using an oil bath. The samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Brunauer-Emmett-Teller specific surface area, surface photocurrent and UV-Vis diffuse reflectance spectroscopy. The photoelectric gas-sensing results demonstrated that the 3D porous, center-hollow ZnO structures exhibited excellent sensitivity and good selectivity to formaldehyde under 365 nm light irradiation at room temperature. The gas response to 1 ppm formaldehyde can reach 70%, which is superior to the results reported in the literature, indicating that the 3D center-hollow ZnO architectures are ideal candidate materials for photoelectric gas sensors. The underlying mechanisms responsible for the high sensitivity and selectivity to formaldehyde are discussed, which provide a new pathway for designing novel VOC sensors. Moreover, the facile method presented in this paper has the advantage of low-cost and high-yield, which is suitable for the practical production processes.

20.
Phys Chem Chem Phys ; 17(44): 29899-905, 2015 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-26488637

RESUMO

A series of Ni@g-C3N4 composites were synthesized by a simple solvent thermal method using melamine and acetylacetone nickel as precursors. The results of X-ray diffraction, transmission electron microscopy and high resolution transmission electron microscopy indicate that Ni was successfully loaded on g-C3N4. And the Ni loaded greatly enhances the photocatalytic H2 evolution activity of g-C3N4 compared to the pure g-C3N4. In order to study the role of Ni, the surface photovoltage, the surface photocurrent and photoluminescence measurements were used to investigate the photogenerated charge properties of g-C3N4. What is more, Mott-Schottky plots and work function measurements confirmed the surface band bending change of g-C3N4 contacting with Ni. Those results demonstrate that Ni coating deepens surface band bending of g-C3N4, resulting in higher separation efficiency of photogenerated charge carriers, which is contributed to the enhanced photocatalytic H2 evolution activity.

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