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1.
Pharm Biol ; 60(1): 1790-1800, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36102587

RESUMO

CONTEXT: Jing-an oral liquid (JA) is a Chinese herbal formula used in the treatment of Tourette syndrome (TS); however, its mechanism is unclear. OBJECTIVE: To investigate the effects of JA on amino acid neurotransmitters and microglia activation in vivo and in vitro. MATERIALS AND METHODS: Sixty male Sprague-Dawley rats were divided into a control group and 5 TS groups. TS was induced in rats with intraperitoneal injection of 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (1 mg/kg) and in BV2 cells with lipopolysaccharide. Control and model rats were administered saline, whereas treatment groups were administered JA (5.18, 10.36, or 20.72 g/kg) or tiapride (a benzamide, 23.5 mg/kg) by gavage once daily for 21 days. Stereotypic behaviour was tested. The levels of N-methyl-d-aspartate receptor (NMDAR)/mitogen-activated protein kinase/cAMP response element-binding protein (CREB)-related proteins in striatum and BV2 cells were measured via western blots. CD11b and IBa1 levels were also measured. Ultra-high-performance liquid-chromatography was used to determine γ-aminobutyric acid (GABA), glutamic acid (Glu), and aspartic acid (ASP) levels. RESULTS: JA markedly alleviated the stereotype behaviour (25.92 ± 0.35 to 13.78 ± 0.47) in rats. It also increased NMDAR1 (0.48 ± 0.09 to 0.67 ± 0.08; 0.54 ± 0.07 to 1.19 ± 0.18) expression and down-regulated the expression of p-ERK, p-JNK, p-P38, and p-CREB in BV2 cells and rat striatum. Additionally, Glu, ASP, GABA, CD11b, and IBa1 levels were significantly decreased by JA. DISCUSSION AND CONCLUSIONS: JA suppressed microglia activation and regulated the levels of amino acid neurotransmitters, indicating that it could be a promising therapeutic agent for TS.


Assuntos
Síndrome de Tourette , Animais , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Ácido Glutâmico , Masculino , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato , Síndrome de Tourette/tratamento farmacológico , Síndrome de Tourette/metabolismo , Ácido gama-Aminobutírico
2.
Nanomaterials (Basel) ; 12(8)2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35458034

RESUMO

Graphene has been considered as an excellent biochemical sensors' substrate material because of its excellent physical and chemical properties. Most of these sensors have employed enzymes, antibodies, antigens, and other biomolecules with corresponding recognition ability as recognition elements, to convert chemical signals into electrical signals. However, oxidoreductase enzymes that grow on graphene surfaces are affected significantly by the environment and are easily inactivated, which hinders the further improvement of detection sensitivity and robusticity. A gold-boosted graphene sensor was fabricated by the in situ electrochemical deposition of inorganic gold nanoparticles on vertical graphene nanosheets. This approach solves the instability of biological enzymes and improves the detection performance of graphene-based sensors. The uric acid sensitivity of the gold-boosted electrode was 6230 µA mM-1 cm-2, which is 6 times higher than the original graphene electrode. A 7 h GNSs/CC electrode showed an impressive detection performance for ascorbic acid, dopamine, and uric acid, simultaneously. Moreover, it exhibited a reliable detection performance in human serum in terms of uric acid. The possible reason could be that the vertical aliened graphene nanosheet acts as a reaction active spot. This 3D graphene-nanosheet-based doping approach can be applied to a wide variety of inorganic catalytic materials to enhance their performance and improve their durability in aspects such as single-atom catalysis and integration of multiple catalytic properties.

3.
Front Bioeng Biotechnol ; 9: 726071, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34616719

RESUMO

Many diseases are closely related to abnormal concentrations of ascorbic acid (AA), dopamine (DA), and uric acid (UA). Therefore, the detection of these small molecules is significant for monitoring life metabolism and healthy states. Electrochemical detection has been widely used to detect small molecules due to its good selectivity, high sensitivity, and good economics. Fabrication and application are two sides of the coin, and we cannot give up one for the other. Graphene (GN) is a very suitable material for electrochemical sensing due to its excellent catalytic performance and large specific surface area. It possesses many excellent properties but cannot hold itself alone due to its nanoscale thickness. Herein, we have fabricated three-dimensional (3D) GN nanosheets (GNSs) on flexible carbon cloth (CC) by thermal chemical vapor deposition (CVD). The GNSs/CC can successfully detect AA, DA, and UA simultaneously. We find that these GNSs/CC sensors show good performance with 7 h CVD modification. The linear ranges of AA, DA, and UA are 0.02-0.1, 0.0005-0.02, and 0.0005-0.02 mM, respectively. The detection sensitivity rates of AA, DA, and UA are 5,470, 60,500, and 64,000 µA mM-1 cm-2, respectively. Our GNSs/CC flexible sensors can be successfully applied in the human serum for UA detection. The result matches with commercial sensors very well.

4.
Nat Commun ; 12(1): 1380, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33654075

RESUMO

Development of excellent and cheap electrocatalysts for water electrolysis is of great significance for application of hydrogen energy. Here, we show a highly efficient and stable oxygen evolution reaction (OER) catalyst with multilayer-stacked hybrid structure, in which vertical graphene nanosheets (VGSs), MoS2 nanosheets, and layered FeCoNi hydroxides (FeCoNi(OH)x) are successively grown on carbon fibers (CF/VGSs/MoS2/FeCoNi(OH)x). The catalyst exhibits excellent OER performance with a low overpotential of 225 and 241 mV to attain 500 and 1000 mA cm-2 and small Tafel slope of 29.2 mV dec-1. Theoretical calculation indicates that compositing of FeCoNi(OH)x with MoS2 could generate favorable electronic structure and decrease the OER overpotential, promoting the electrocatalytic activity. An alkaline water electrolyzer is established using CF/VGSs/MoS2/FeCoNi(OH)x anode for overall water splitting, which generates a current density of 100 mA cm-2 at 1.59 V with excellent stability over 100 h. Our highly efficient catalysts have great prospect for water electrolysis.

5.
ACS Appl Mater Interfaces ; 12(42): 47623-47633, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33047606

RESUMO

The ever-growing demand for energy in the consumer market has put higher requirements on the energy density of Li-ion batteries. Many researchers have strived to discover new electrode materials with higher capacity, while little attention has been focused on improving the cell structure. How to increase the thickness of conventional slurry-cast electrodes as well as decrease the charge transfer resistance by improving the electrode structure is an urgent problem for enhancing the energy density of Li-ion batteries. Here, a porous Cu film is developed to replace the conventional Cu foil current collector, and a thick graphite anode (300 µm) is engineered by two-side slurry casting. The anode delivers a maximum capacity of 18 mAh cm-2 or 301.3 mAh g-1 under a highly active mass loading of 60 mg cm-2, much higher than that fabricated on Cu foil. The assembled full cell with the graphite anode and the LiFePO4 cathode achieves high energy densities of 36.2 mWh cm-2 and 283.3 Wh kg-1. Systematic experimental and simulation investigations reveal the enhanced performance benefits from the facilitated charge transfer efficiency by the porous Cu current collector. This work provides a new strategy for engineering thick electrodes for high-energy Li-ion batteries by improving the conventional electrode structure.

6.
ACS Appl Mater Interfaces ; 10(35): 29866-29875, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-30085645

RESUMO

Diamond/graphite hybrid nanosheets (DGNSs) have been epitaxially grown on boron-doped diamond (BDD) films from CH4/H2 mixture gas by microwave plasma chemical vapor deposition. The DGNSs are vertically aligned on the crystal facets of the BDD films uniformly, densely, and orderly. The DGNSs are composed of the core diamond sheets and the surface graphitic overlayers, which possess an open edge structure. By posttreatment in NH3 atmosphere in a microwave plasma or a tube furnace, the N-doped DGNSs (NDGNSs) were obtained. The electrocatalytic performance toward oxygen reduction reaction (ORR) for the DGNSs was greatly enhanced after doping with N, and the doped pyridinic N contributes more to the ORR. The electrocatalytic activity for ORR of the NDGNSs doped at 650 °C in NH3 in a tube furnace is the highest in all of the samples, which is comparable to the commercial Pt/C. The present work provides a novel electrocatalyst for the ORR with high performance.

7.
Adv Mater ; 30(12): e1705380, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29423926

RESUMO

3D assembly of graphene sheets (GSs) is important for preserving the merits of the single-atomic-layered structure. Simultaneously, vertical growth of GSs has long been a challenge for thermal chemical vapor deposition (CVD). Here, vertical growth of the GSs is achieved in a thermal CVD reactor and a novel 3D graphene structure, 3D graphene fibers (3DGFs), is developed. The 3DGFs are prepared by carbonizing electrospun polyacrylonitrile fibers in NH3 and subsequently in situ growing the radially oriented GSs using thermal CVD. The GSs on the 3DGFs are densely arranged and interconnected with the edges fully exposed on the surface, resulting in high performances in multiple aspects such as electrical conductivity (3.4 × 104 -1.2 × 105 S m-1 ), electromagnetic shielding (60 932 dB cm2 g-1 ), and superhydrophobicity and superoleophilicity, which are far superior to the existing 3D graphene materials. With the extraordinary properties along with the easy scalability of the simple thermal CVD, the novel 3DGFs are highly promising for many applications such as high-strength and conducting composites, flexible conductors, electromagnetic shielding, energy storage, catalysis, and separation and purification. Furthermore, this strategy can be widely used to grow the vertical GSs on many other substrates by thermal CVD.

8.
Nanoscale ; 10(6): 2812-2819, 2018 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-29360122

RESUMO

Three-dimensional ordering of two-dimensional nanomaterials has long been a challenge. Simultaneously, diamond nanomaterials are difficult to synthesize due to the harsh synthesizing conditions required. Here, we report substrate-crystal-orientation dependent growth of diamond nanosheets (DNSs) by chemical vapor deposition, which generates different DNS arrays on different substrates. The DNSs are grown by the in-plane epitaxy of the diamond {111} planes. So the arrays are highly ordered and solely determined by the spatial orientation of the {111} planes in the diamond FCC structure. The DNSs grown on the {110}, {111}, {001}, and {113} oriented substrates show inclination angles ranging from 90 to 29.5°. The DNSs with larger inclination angles grow preferentially, forming parallelogram arrays with inclination angles of 90° on the {110} substrates and parallel-line arrays with inclination angles of 80° on the {113} substrates. The density, thickness, size, and morphology of the DNSs have been well controlled. The present understanding and materials are highly promising for many applications such as sensors, catalysis, photonics, thermal management, and electronics.

9.
ACS Appl Mater Interfaces ; 7(3): 1824-32, 2015 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-25552343

RESUMO

Here, we report the synthesis of nanosheet-structured boron nitride spheres (NSBNSs) by a catalyzing thermal evaporation method from solid B powders. The NSBNSs consist of radially oriented ultrathin nanosheets with the sheet edges oriented on the surface. Formation of this unique structure occurs only at a certain reaction temperature. The diameter from 4 µm to 700 nm and the nanosheet thickness from 9.1 to 3.1 nm of the NSBNSs can be well-controlled by appropriately changing the mass ratio of boron powders and catalyst. The NSBNSs possess versatile adsorption capacity, exhibiting excellent adsorption performance for oil, dyes, and heavy metal ions from water. The oil uptake reaches 7.8 times its own weight. The adsorption capacities for malachite green and methylene blue are 324 and 233 mg/g, while those for Cu(2+), Pb(2+), and Cd(2+) are 678.7, 536.7, and 107.0 mg/g, respectively. The adsorption capacities of the NSBNSs for Cu(2+) and Pb(2+) are higher or much higher than those of the adsorbents reported previously. These results demonstrate the great potential of NSBNSs for water treatment and cleaning.

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