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1.
Free Radic Biol Med ; 160: 820-836, 2020 11 20.
Article in English | MEDLINE | ID: mdl-32950688

ABSTRACT

Brahma-related gene 1 (BRG1) regulates the chromatin structure and expression of cardiac genes. Although BRG1 is downregulated in adult cardiomyocytes, it is reactivated during cardiac stress. The role of BRG1 in acute myocardial infarction (AMI) has not been clearly defined. This study assessed the protective role of BRG1 in AMI using cell cultures and an animal model and explored the underlying molecular events. The results showed that in the peri-infarct zone, expression of BRG1 protein was significantly increased relative to the sham group, which was accompanied by NRF2 and HO1 upregulation and KEAP1 downregulation. BRG1 overexpression through adenoviral intramyocardial injection into AMI mice reduced the infarct size and improved cardiac functions with upregulation of NRF2 and its target HO1 and attenuated oxidative damage and cell apoptosis. However, shRNA-mediated Brg1 knockdown had the opposite effects. These results were further confirmed in cultured primary neonatal rat cardiomyocytes (NRCMs) with oxygen-glucose deprivation (OGD). Moreover, the selective NRF2 inhibitor brusatol could partially reverse cardiomyocyte antioxidant ability and BRG1 overexpression-induced cardiac protection in vitro. In addition, co-immunoprecipitation and immunofluorescence data showed that BRG1 overexpression significantly promoted the BRG1/NRF2 co-localization in cardiomyocytes. The chromatin immunoprecipitation-qPCR revealed BRG1 interaction with the Ho1 promoter and BRG1 overexpression could induce BRG1 binding to the Ho1 promoter during the OGD. In conclusion, this study demonstrated that BRG1 upregulation during AMI in vitro and in vivo increased the NRF2 level and NRF2 nuclear accumulation for HO1 expression to alleviate cardiac myocyte oxidative stress and upregulate cardiomyocyte viability. The BRG1-NRF2-HO1 pathway may represent a novel therapeutic target in the prevention of cardiac dysfunction in AMI patients.


Subject(s)
DNA Helicases , Myocardial Infarction , NF-E2-Related Factor 2 , Nuclear Proteins , Oxidative Stress , Transcription Factors , Animals , Apoptosis , Cell Line , Heme Oxygenase-1 , Kelch-Like ECH-Associated Protein 1/genetics , Membrane Proteins , Mice , Myocardial Infarction/genetics , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Rats , Signal Transduction
2.
J Environ Sci (China) ; 87: 39-48, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31791512

ABSTRACT

Carbon-silica materials with hierarchical pores consisting of micropores and mesopores were prepared by introducing nanocarbon microspheres derived from biomass sugar into silica gel channels in a hydrothermal environment. The physicochemical properties of the materials were characterized by nitrogen physical adsorption (BET), scanning electron microscopy (SEM), and thermogravimetric (TG), and the adsorption properties of various organic waste gases were investigated. The results showed that microporous carbon materials were introduced successfully into the silica gel channels, thus showing the high adsorption capacity of activated carbon in high humidity organic waste gas, and the high stability and mechanical strength of the silica gel. The dynamic adsorption behavior confirmed that the carbon-silica material had excellent adsorption capacity for different volatile organic compounds (VOCs). Furthermore, the carbon-silica material exhibited excellent desorption characteristics: adsorbed toluene was completely desorbed at 150°C, thereby showing superior regeneration characteristics. Both features were attributed to the formation of hierarchical pores.


Subject(s)
Models, Chemical , Volatile Organic Compounds/chemistry , Adsorption , Biomass , Charcoal , Humidity , Hydrophobic and Hydrophilic Interactions , Microspheres , Porosity , Silicon Dioxide/chemistry , Toluene/chemistry
3.
J Vis Exp ; (148)2019 06 12.
Article in English | MEDLINE | ID: mdl-31259906

ABSTRACT

We demonstrate a method for the enhancement of CO2 photoreduction. As the driving force of a photocatalytic reaction is from solar light, the basic idea is to use concentration technology to raise the incident solar light intensity. Concentrating a large-area light onto a small area cannot only increase light intensity, but also reduce the catalyst amount, as well as the reactor volume, and increase the surface temperature. The concentration of light can be realized by different devices. In this manuscript, it is realized by a Fresnel lens. The light penetrates the lens and is concentrated on a disc-shaped catalyst. The results show that both the reaction rate and the total yield are efficiently increased. The method can be applied to most CO2 photoreduction catalysts, as well as to similar reactions with a low reaction rate at natural light.


Subject(s)
Carbon Dioxide/metabolism , Sunlight , Catalysis
4.
Talanta ; 185: 221-228, 2018 Aug 01.
Article in English | MEDLINE | ID: mdl-29759192

ABSTRACT

A novel polystyrene-divinylbenzene microspheres hybridized with oxidized nanodiamonds (PS-DVB-OND) was synthesized by the method of seed swelling and polymerization. The oxidized nanodiamonds (OND) were characterized by Fourier transform infrared (FTIR) spectra, X-ray phtoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), X-ray diffraction (XRD). PS-DVB-OND particles were characterized by scanning electron microscopy (SEM) and transmission electron microscope (TEM). The result suggested that OND were successfully embedded into the polymer microspheres with the diameter of 6 ±â€¯2 µm. Compared to polystyrene-divinylbenzene (PS-DVB) microspheres, PS-DVB-OND microspheres could tolerate higher pressure. The PS-DVB-OND microspheres were used as stationary phase of reversed-phase liquid chromatography directly and anion-exchangers after further quaternized with methylamine and 1,4-butanediol diglycidyl ether. Reversed-phase liquid chromatographic performance of PS-DVB-OND beads was investigated through separating six benzenes such as toluene, benzaldehyde, phenol, benzoic acid, 1,4-hydroquinone and methyl p-hydroxybenzoate. Inorganic anions such as F-, Cl-, NO2-, Br-, NO3-, HPO42- and SO42-, were baseline separated on the anion exchangers of PS-DVB-OND microspheres. The result suggested that the prepared PS-DVB-OND microspheres have the potential as liquid chromatographic stationary phase under high pressure and extremely pH conditions.

5.
RSC Adv ; 8(27): 14806-14811, 2018 Apr 18.
Article in English | MEDLINE | ID: mdl-35541327

ABSTRACT

We report a facile and general strategy for the preparation of metallic monolithic catalysts. Our strategy involved subjecting the surfaces of FeCrAl fibers to thermal treatment and the spraying of Pt nanoparticles suspension liquid. The catalyst exhibited high catalytic activity and good stability in the combustion of volatile organic compounds to CO2 and H2O at mild temperature. The exceptional activity of the catalyst can be attributed to the well-adhered alumina coating that formed on the surfaces of the FeCrAl fibers after thermal treatment and the highly dispersed Pt nanoparticles on the surface of the alumina coating.

6.
Yao Xue Xue Bao ; 51(6): 961-4, 2016 06.
Article in Chinese | MEDLINE | ID: mdl-29883073

ABSTRACT

Two new flavonoid glycosides were isolated from the aerial parts of Nervilia fordii by various chromatographies such as D101 macroporous resin, ODS and preparative HPLC chromatographic techniques. Their structures were elucidated as rhamnocitrin-3-O-ß-glucopyranosyl-4'-O-ß-galactosyl-(1→3)-glucopyranoside(1) and 7,3'-di-O-methylquercetin-4'-O-[ß-galactosyl-(1→3)-ß-glucopyranosyl]-3-O-ß-glucopyranoside(2) on the basis of extensive spectroscopic analyses, including 1D-, 2D-NMR, HR-ESI-MS and analytical hydrolysis.


Subject(s)
Flavonoids/isolation & purification , Glycosides/isolation & purification , Orchidaceae/chemistry , Chromatography, High Pressure Liquid , Drugs, Chinese Herbal/chemistry , Hydrolysis , Molecular Structure
7.
Nat Commun ; 6: 8446, 2015 Oct 15.
Article in English | MEDLINE | ID: mdl-26469151

ABSTRACT

The development of noble-metal-free heterogeneous catalysts that can realize the aerobic oxidation of C-H bonds at low temperature is a profound challenge in the catalysis community. Here we report the synthesis of a mesoporous Mn0.5Ce0.5Ox solid solution that is highly active for the selective oxidation of hydrocarbons under mild conditions (100-120 °C). Notably, the catalytic performance achieved in the oxidation of cyclohexane to cyclohexanone/cyclohexanol (100 °C, conversion: 17.7%) is superior to those by the state-of-art commercial catalysts (140-160 °C, conversion: 3-5%). The high activity can be attributed to the formation of a Mn0.5Ce0.5Ox solid solution with an ultrahigh manganese doping concentration in the CeO2 cubic fluorite lattice, leading to maximum active surface oxygens for the activation of C-H bonds and highly reducible Mn(4+) ions for the rapid migration of oxygen vacancies from the bulk to the surface.

8.
Ying Yong Sheng Tai Xue Bao ; 24(4): 983-8, 2013 Apr.
Article in Chinese | MEDLINE | ID: mdl-23898655

ABSTRACT

Taking the rhizosphere and non-rhizosphere soils of five typical plants Agropyron cristatum, Artemisia frigida, Pseudoraphis bungeana, Thymus mongolicus, and Artemisia sacrorum in a mountainous area of southern Ningxia as test objects, this paper studied their C and N forms contents. The C and N forms contents in the rhizosphere and non-rhizosphere soils differed with plant species. In the rhizosphere soil of A. sacrorum, the C content was the highest, with the total soil organic C (TOC), light fraction organic C (LFOC), and heavy fraction organic C contents being 22.94, 1.95, and 20. 88 g kg-1, respectively. In the rhizosphere soil of P. bungeana, the N content was the highest, with the total N (TN), mineralizable N (MN), and available N contents being 2.05 g kg-1 , 23.73 mg kg-1, and 11.99 mg kg-1 , respectively. In the rhizosphere soil of A. frigida, the LFOC/TOC and MN/TN ratios were the highest, which benefited the C and N transformed into more active forms. Light fraction organic C and mineralizable N could be used as the sensitive indicators of plant habitat change. For the five plant species, the contents of different C and N forms in the rhizosphere soil were generally higher than those in the non-rhizosphere soil.


Subject(s)
Carbon/chemistry , Nitrogen/chemistry , Plant Roots/metabolism , Plants/metabolism , Rhizosphere , Agropyron/metabolism , Altitude , Artemisia/metabolism , China , Ecosystem , Thymus Plant/metabolism
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