Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 63
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Chem Asian J ; 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32212305

RESUMO

Niobium nitrides possess superconductivity and stable chemical stability, which render them desirable candidates for energy storage. Therefore, they deserve exploration in potential application for energy storage. Here we report on synthesis of 2D Nb4N5 nanosheets by ammonization of NbS2 nanosheets as template at 700 °C. The obtained 2D Nb4N5nanosheets retain hexagon shape and display porous structure with pore size of 3.716 nm. These 2D Nb4N5 nanosheets exhibit capacitor behavior as electrode materials for energy storage. This study opens a new avenue in synthesizing 2D materials based on 2D templates.

2.
Sci Total Environ ; 715: 137018, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32041003

RESUMO

Antibacterial polymer membranes have been widely used in many fields of our daily life. In this study, porous PA6 membrane with ZnO nanoparticles attaching on to the surface of inner pore walls is prepared. Firstly, SMA (styrene maleic anhydride copolymer) is used to graft onto the surface of ZnO nanoparticle in DMF (dimethylformamide). Then the pre-treated ZnO nanoparticles (ZnO-SMA) are added into SEBS (Styrene-ethylene-butylene-styrene copolymer)/PA6 (60/40 wt/wt) blends with co-continuous morphology. The effects of SMA molecular structure (molecular weight and maleic anhydride content) used for ZnO-SMA nanoparticles on their dispersion states in SEBS/PA6/ZnO-SMA nanocomposites are investigated. When SMA3 (MAH = 8 wt%, Mn = 250,000 g mol-1), which has relatively higher molecular weight and lower MAH content, is used as the pre-treating agent, ZnO-SMA3 nanoparticles tend to be dispersed at the phase interface in SEBS/PA6/ZnO-SMA nanocomposites. However, when SMA2 (MAH = 23 wt%, Mn = 110,000 g mol-1) with relatively lower molecular weight and higher MAH content is used, no ZnO-SMA2 nanoparticles locate at the interface but stay within PA6 phase. Porous PA6 membranes are obtained by selectively etching SEBS phase out with xylene. It can be found that porous PA6 membrane containing ZnO-SMA3 nanoparticles still exhibits much better antibacterial property (R = 3.76) toward S. aureus even at a very low ZnO content (0.5 wt%). This result should be ascribed to almost all the ZnO-SMA3 nanoparticles being exposed to the surface of inner pore walls of PA6 membrane. This work proposes an effective method to prepare porous polymer membrane with functional nanoparticles selectively located at the inner pore walls.

3.
Adv Mater ; 32(8): e1906939, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31945238

RESUMO

Polymer-based thermal management materials have many irreplaceable advantages not found in metals or ceramics, such as easy processing, low density, and excellent flexibility. However, their limited thermal conductivity and unsatisfactory resistance to elevated temperatures (<200 °C) still prevent effective heat dissipation during applications with high-temperature conditions or powerful operation. Therefore, herein highly thermoconductive and thermostable polymer nanocomposite films prepared by engineering 1D aramid nanofiber (ANF) with worm-like microscopic morphologies into rigid rod-like structures with 2D boron nitride nanosheets (BNNS) are reported. With no coils or entanglements, the rigid polymer chain enables a well-packed crystalline structure resulting in a 20-fold (or greater) increase in axial thermal conductivity. Additionally, strong interfacial interactions between the weaved ANF rod and the stacked BNNS facilitate efficient heat flux through the 1D/2D configuration. Hence, unprecedented in-plane thermal conductivities as high as 46.7 W m-1 K-1 can be achieved at only 30 wt% BNNS loading, a value of 137% greater than that of a worm-like ANF/BNNS counterpart. Moreover, the thermally stable nanocomposite films with light weight (28.9 W m-1 K-1 /103 (kg m-3 )) and high strength (>100 MPa, 450 °C) enable effective thermal management for microelectrodes operating at temperatures beyond 200 °C.

4.
Phys Chem Chem Phys ; 22(5): 3112-3121, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-31967127

RESUMO

The presence of unpaired electrons (radicals) due to structural defects is believed to contribute to the catalytic reactivity of carbon materials. Graphite oxide and graphene oxide (GO) consist of significant structural defects and hence are considered more reactive than graphite and graphene. However, the relationship between their radical content/reactivity and their physical and chemical structures remains unknown, which limits the fabrication of high efficiency carbon-based catalysts. In this work, we progressively oxidize graphite to achieve graphite oxide and GO with different levels of oxidation and different sizes. It is observed that a maximal radical content can be achieved on graphite oxide with a C/O ratio of ca. 3.0 and a thickness of around 50 nm. Such a graphite oxide contains about 45% of π bonds and 38% of oxygenated bonds, respectively. Thinner or thicker sheets have lower radical contents due to over or insufficient oxidation, respectively. Single GO sheets with high radical contents can only be produced through a combination of oxidation and reduction. The catalytic activity of the graphite/graphene oxide for phenol degradation was found to be linearly correlated to their radical contents. The observations are significant for the advancement of carbon-based metal-free catalysis.

5.
Nanotechnology ; 31(14): 145716, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-31899904

RESUMO

Polytriazine imide (PTI), a triazine-based carbon nitride has a wider band gap and more positive conduction band (CB) potential compared to those of graphitic carbon nitride (g-C3N4). Therefore, it is highly desired to develop an effective strategy to optimize the band structure of PTI for the enhancement of the photocatalytic performance, especially upshift the conductive band potential. Here, a ternary C-PTI/ZnO (CPZ) photocatalyst was developed via a simple one-step molten salt method. In the obtained CPZ sample, the carbon ring in-plane connects to the triazine ring, leading to the formation of C-PTI nanosheets. The carbon ring incorporation not only efficiently narrows the band gap of PTI, but also shifts its conduction band potential negatively and accelerates the photogenerated electron transport. In addition, ZnO nanoparticles are well dispersed on the C-PTI nanosheets, further promoting the charge carriers transfer and separation. As a result, the CPZ sample presents a photocatalytic H2 evolution rate up to 52 µmol h-1 under visible light, which is 60 and 179 times higher than that of C-PTI and PTI, respectively.

6.
Cell Commun Signal ; 17(1): 162, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31823782

RESUMO

BACKGROUND: Interleukin-22 (IL-22) belongs to the IL-10 cytokine family and is mainly produced by activated Th1 cells. Although IL-22 expression is reported to be elevated in many cancers, and increased IL-22 expression correlates with tumor progression and poor prognosis, little is known about the role of IL-22 in papillary thyroid cancer (PTC). We previously demonstrated that IL-22 promotes PTC cell migration and invasion through the microRNA-595/Sox17 axis. METHODS: We used qRT-PCR and western blot to determine TRIM30, Sox17 and ß-catenin expression in PTC cells. Knockdown and overexpression were performed to detect the role of TRIM30/Sox17/ß-catenin axis on the migration and invasion PTC cells. Co-IP were used to determine the interaction between TRIM30 and Sox17. FINDINGS: In this study, we demonstrated that IL-22 triggered tripartite-motif protein 30 (TRIM30) association with Sox17, thereby mediating K48-linked polyubiquitination of Sox17. We then demonstrated that TRIM30 was a positive regulator of IL-22-regulated migration and invasion of PTC cells. We also found that IL-22 induced the transcriptional activity of ß-catenin and translocation of ß-catenin from cytosol to the nucleus. Upon investigating the mechanisms behind this event, we found that IL-22 disrupted Sox17/ß-catenin interactions by inducing TRIM30/Sox17 interactions, leading to promotion of ß-catenin-dependent signaling. The analysis of hundreds of clinical specimens revealed that IL-22, TRIM30 and ß-catenin levels were upregulated in PTC tissues compared with normal thyroid, and that their expression levels were closely correlated. Taken together, under the influence of IL-22, by sequestration of Sox17, TRIM30 promotes ß-catenin-dependent signaling that promotes PTC cell proliferation.

7.
Polymers (Basel) ; 11(11)2019 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-31744215

RESUMO

A novel elastomer poly(diethyl itaconate-co-butyl acrylate-co-ethyl acrylate-co-glycidyl methacrylate) (PDEBEG) was designed and synthesized by redox emulsion polymerization based on bio-based diethyl itaconate, butyl acrylate, ethyl acrylate, and glycidyl methacrylate. The PDEBEG has a number average molecular weight of more than 200,000 and the yield is up to 96%. It is easy to control the glass transition temperature of the PDEBEG, which is ranged from -25.2 to -0.8 °C, by adjusting the monomer ratio. We prepared PDEBEG/CB composites by mixing PDEBEG with carbon black N330 and studied the oil resistance of the composites. The results show that the tensile strength and the elongation at break of the composites with 10 wt% diethyl itaconate can reach up to 14.5 MPa and 305%, respectively. The mechanical properties and high-temperature oil resistance of the composites are superior to that of the commercially available acrylate rubber AR72LS.

8.
Adv Sci (Weinh) ; 6(21): 1900762, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31728275

RESUMO

For most carbon-based materials, hierarchical porous structure including well-defined macropores, mesopores, and micropores is commonly seen in 3D aerogels, monoliths, or some carbothermic natural biomass. However, because of the filiform character and long draw ratio, it is difficult to achieve such pore network as well as attain excellent mechanical performance in a 1D single carbon fiber system. To address this issue, an innovative hierarchical porous and hollow carbon textile (HPHCT) is developed via the "dynamic template (KOH, SiO2, and Al2O3) calcination" strategy. Unlike conventional one-step activated carbonized fiber simply with meso or micropores, the fabricated textile generates honeycomb-like macropores uniformly spreading on fiber surface. More importantly, the ultra-lightweight yet flexible HPHCT is mechanically robust, superior to ordinary carbonized one. In addition, it delivers high capacitance of maximum 220 F g-1 as well as keeping long term stability with 100% retention after 10 000 cycles as freestanding electrodes in supercapacitor. Meanwhile, the all-solid integrated symmetric HPHCT supercapacitors demonstrates its high potential in powering electronics for wearable energy storage application.

9.
ACS Appl Mater Interfaces ; 11(33): 30430-30436, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31318530

RESUMO

Porous membranes play an important role in the separation technologies such as gas purification, solute nanofiltration, and desalination. An ideal membrane should be thin to maximize permeation speed, have optimum pore sizes to maximize selectivity, and be stable in various harsh conditions. Here, we show that the nanometer-thick membrane prepared by means of filtration of functionalized boron nitride (FBN) water suspensions can block solutes with hydrated radii larger than 4.3 Å in water. The FBN membranes with abundant nanochannels reduce the path length of ions. As molecular sieves, the FBN membrane can permeate small ions at an ultrahigh rate-a 25-fold enhancement compared with that of its theoretical diffusion rate and much higher than the graphene oxide membrane. Importantly, the FBN membrane exhibits excellent permeability even when it is immersed in acidic, alkaline, and basic salts solutions because of its intrinsic chemical stability. The molecular dynamics simulations further confirmed that the nanocapillaries formed within the FBN membrane in the hydrated state were responsible for high permeation performance. The simple vacuum filtration fabricated FBN membrane with angstrom-sized channels and ultrafast permeation of ions promises great potential applications in the areas of barrier separation and water purification.

10.
Langmuir ; 35(48): 15834-15848, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31355643

RESUMO

Lubricin (LUB, aka PRG4), a mucin-like glycoprotein, is best known for the significant role it plays in the boundary lubrication, wear protection, and adhesion control systems in human joints. However, LUB exhibits a number of diverse and useful properties, including a remarkable ability to self-assemble into a telechelic brush structure onto virtually any substrate. This self-assembly behavior has spawned the emergence of numerous nontraditional applications of LUB coatings in numerous areas such as microfluidics, electrochemical sensors, contact lenses, antifouling surfaces, and bionic neural interfaces. Although LUB will readily self-assemble on most substrates, it has become apparent that the substrate has a significant influence on the LUB layer's demonstrated lubrication, antiadhesion, electrokinetic, and size-selective transport properties; however, investigations into LUB-substrate interactions and how they influence the self-assembled LUB layer structure remain a neglected aspect of LUB research. This study utilizes AFM force spectroscopy to directly assess the adhesion energy of LUB molecules adsorbed to a wide variety of different substrates which include inorganic, polymeric, and metallic materials. An analysis of the steric repulsive forces measured on approach provides a qualitative assessment of the LUB layer's mechanical modulus, related to the chain packing density, across substrates. These modulus measurements, combined with characteristic features and the dwell time dependence of the LUB adhesion forces provide insight into the organization and uniformity of the LUB brush structure. The results of these measurements indicate that LUB interactions with different substrates are highly variable and substrate-specific, resulting in a surprisingly broad spectrum of adhesion energies and layer properties (i.e., chain density, uniformity, etc.) which are not, themselves, correlated or easily predicted by substrate properties. In addition, this study finds exceptionally poor LUB adhesion to both mica and poly(methyl methacrylate) surfaces that remain widely used substrates for constructing model surfaces in fundamental tribology studies which may have significant implications for the findings of a number of foundational studies into LUB tribology and molecular synergies.

11.
ACS Nano ; 13(7): 7860-7870, 2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31194502

RESUMO

Conventional three-dimensional (3D) thermal conductors or heat sinks are normally bulky solids with high density, which is cumbersome and not portable to satisfy current demands for soft and flexible electronic devices. To address this issue, here, a lightweight, superelastic yet thermally conductive boron nitride (BN) nanocomposite aerogel is designed by a facile freeze-drying method. The attained aerogel constituting of tailored interconnected binary inorganic-organic network structure exhibits low bulk density (6.5 mg cm-3) and outstanding mechanical performances for compression, clotting, and stretching. Meanwhile, the aerogel has promising thermal stability and high thermal conductivity over wide temperature ranges (30-300 °C), validating the application even in extremely hot environments. Moreover, the aerogel can serve as a lightweight and elastic heat conductor for the enhancement of thermal energy harvest. Interestingly, during alternate strain loading/unloading under heating, the superelasticity and the anisotropy of thermal conductive transduction make the aerogel enable the elastic thermal energy capture and dynamic regulation. Therefore, our findings provide a potential use for the thermally conductive aerogel in future green energy applications.

12.
Chem Senses ; 44(5): 339-347, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31066447

RESUMO

Divalent and trivalent salts exhibit a complex taste profile. They are perceived as being astringent/drying, sour, bitter, and metallic. We hypothesized that human bitter-taste receptors may mediate some taste attributes of these salts. Using a cell-based functional assay, we found that TAS2R7 responds to a broad range of divalent and trivalent salts, including zinc, calcium, magnesium, copper, manganese, and aluminum, but not to potassium, suggesting TAS2R7 may act as a metal cation receptor mediating bitterness of divalent and trivalent salts. Molecular modeling and mutagenesis analysis identified 2 residues, H943.37 and E2647.32, in TAS2R7 that appear to be responsible for the interaction of TAS2R7 with metallic ions. Taste receptors are found in both oral and extraoral tissues. The responsiveness of TAS2R7 to various mineral salts suggests it may act as a broad sensor, similar to the calcium-sensing receptor, for biologically relevant metal cations in both oral and extraoral tissues.

13.
Soft Matter ; 15(18): 3680-3688, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-30892366

RESUMO

Many living tissues possess excellent mechanical properties and water retention which enable them to self-heal at room temperature even below the freezing temperature of water. To mimic the unique features of living tissue, a poly(acrylic acid-co-maleic acid) composite hydrogel with enhanced mechanical properties and remarkable water retention was fabricated under accessible conditions. The hydrogel is functionalized by amino group modified boron nitride nanosheets (BNNS-NH2)/glycerol and exhibits self-healing abilities at low temperature. The self-healing process occurs through the re-establishing of hydrogen bonds and metal coordination interactions at the damaged surfaces. Its anti-freezing abilities enable the hydrogel to self-heal at -15 °C, and the self-healing efficiency based on tensile strength reaches up to ∼70%. Moreover, glycerol also endows the hydrogel with long-lasting water retention, which remains a water content of ∼99 wt% for more than 30 days. Meanwhile, the simultaneous introduction of BNNS-NH2 and glycerol significantly improved the mechanical properties of the hydrogel, which displays great stretchability (∼474%), tensile strength (∼151.3 kPa), stiffness (Young's modulus of ∼62.75 kPa) and toughness (∼355.13 kJ m-3). It is anticipated that these novel hydrogels will develop many fields and be exploited for new applications in extensive external environments.

14.
ACS Appl Mater Interfaces ; 11(10): 10276-10282, 2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30742403

RESUMO

Without any extra directing agents or surfactants, three-dimensional (3D) hierarchically cubic and spherical morphologies of functionalized boron nitride nanosheets (FBNNSs)/ZnO superstructures have been controlled successfully via the evaporation-induced solvothermal synthesis. As-resulted spherical FBNNSs/ZnO superstructures not only exhibit a high capture capacity of CO2 around 63.4 cm3/g (124.5 mg/g) from 0 to 1 bar at 273 K but also show a good reusability of 10 cycles with an average removal ability up to 58.9 cm3/g (115.7 mg/g). The excellent adsorption property can be further explained by the chemisorption, van der Waals interaction, and H bonds from the surface of ZnO and the in-plane and edged amino groups of FBNNS. Therefore, the preparation of 3D FBNNSs/ZnO superstructures provides a new and promising material for CO2 adsorption with tunable morphologies.

15.
Nanoscale Res Lett ; 13(1): 393, 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30519840

RESUMO

Many living tissues possess excellent mechanical properties and self-healing ability. To mimic these living tissues, a series of novel composite hydrogels, poly(acrylic acid)/surface-modified boron nitride nanosheets (PAA/BNNS-NH2) were fabricated simply through hierarchically physical interactions: molecular-scale metal coordination interaction between -COOH of PAA and Fe3+ and nanoscale H-bond between -COOH of PAA and -NH2 of BNNS-NH2. The composite hydrogels exhibit both excellent mechanical properties (including enhanced fracture stress, elongation, toughness, Young's modulus, and dissipated energy) and rapid healing ability without any external stimulus. Especially, the B0.5P70 (the hydrogel with BNNS concentration of 0.5 mg mL- 1, the water content of 70 wt%) exhibits a fracture stress of ~ 1311 kPa and toughness of ~ 4.7 MJ m- 3, almost ~ 3 times and ~ 8 times to B0P70, respectively. The excellent properties, combined with the simple preparation method, endow these composite hydrogels with potential applications.

16.
Nanoscale ; 10(35): 16868-16872, 2018 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-30168552

RESUMO

Recently, thermally regulating textiles have attracted wide interest owing to their ability to realize personal cooling and provide thermal comfort. However, most of the thermally conductive textiles cannot afford higher temperatures (>200 °C), which restricts their further applications in aviation, fire extinguishing or military requiring high temperature heat spreaders. Here, we report a high temperature thermally conductive nanocomposite textile consisting of amino functional boron nitride (FBN) nanosheets and polyimide (PI) nanofibers. Notably, the textile is "green" electrospun from aqueous solution without any toxic organic solvents, which is facile, economical and environmently friendly. Moreover, both FBN and the precursor of PI are modified to be water soluble and exhibit good compatibility in the spinning solution even under high concentrations. The "green" method obtained FBN-PI textile shows high thermal conductivity (13.1 W m-1 K-1) at a high temperature (300 °C), filling in the gap of thermally conductive polymer nanocomposite fibers for high temperature thermal regulation. Furthermore, it also provides efficient cooling capability as a thermal spreader. The good performance is ascribed to the weaving of the aligned FBN filament in a thermally stable PI fiber, which constructs an effective thermally conductive network. In addition, the nanocomposite textile is light weight, soft and hydrophobic, which is promising for electronic packaging or space suits for special high temperature thermal management.

17.
ACS Nano ; 12(9): 9266-9278, 2018 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-30179445

RESUMO

The combination of high strength, great toughness, and high heat resistance for polymeric materials is a vital factor for their practical applications. Unfortunately, until now it has remained a major challenge to achieve this performance portfolio because the mechanisms of strength and toughness are mutually exclusive. In the natural world, spider silk features the combination of high strength, great toughness, and excellent thermal stability, which are governed by the nanoconfinement of hydrogen-bonded ß-sheets. Here, we report a facile bioinspired methodology for fabricating advanced polymer composite films with a high tensile strength of 152.8 MPa, a high stiffness of 4.35 GPa, and a tensile toughness of 30.3 MJ/m3 in addition to high thermal stability (69 °C higher than that of the polymer matrix) only by adding 2.0 wt % of artificial ß-sheets. The mechanical and thermostable performance portfolio is superior to that of its counterparts developed to date because of the nanoconfinement and hydrogen-bond cross-linking effects of artificial ß-sheets. Our study offers a facile biomimetic strategy for the design of integrated mechanically robust and thermostable polymer materials, which hold promise for many applications in electrical devices and tissue engineering fields.


Assuntos
Nanoestruturas/química , Polímeros/química , Temperatura Ambiente , Teste de Materiais , Tamanho da Partícula , Propriedades de Superfície , Engenharia Tecidual
18.
Small ; 14(37): e1802225, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30084530

RESUMO

Yarn-shaped supercapacitors (YSCs) once integrated into fabrics provide promising energy storage solutions to the increasing demand of wearable and portable electronics. In such device format, however, it is a challenge to achieve outstanding electrochemical performance without compromising flexibility. Here, MXene-based YSCs that exhibit both flexibility and superior energy storage performance by employing a biscrolling approach to create flexible yarns from highly delaminated and pseudocapacitive MXene sheets that are trapped within helical yarn corridors are reported. With specific capacitance and energy and power densities values exceeding those reported for any YSCs, this work illustrates that biscrolled MXene yarns can potentially provide the conformal energy solution for powering electronics beyond just the form factor of flexible YSCs.

19.
Adv Sci (Weinh) ; 5(7): 1800062, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30027039

RESUMO

Heterojunction photocatalysts at present are still suffering from the low charge separation/transfer efficiency due to the poor charge mobility of semiconductor-based photocatalysts. Atomic-scale heterojunction-type photocatalysts are regarded as a promising and effective strategy to overcome the drawbacks of traditional photocatalysts for higher photoenergy conversion efficiencies. Herein, an atomic-scale heterojunction composed of a boron nitride monolayer and graphene (h-BN-C/G) is constructed to significantly shorten the charge transfer path to promote the activation of molecular oxygen for artificial photosynthesis (exemplified with oxidative coupling of amines to imines). As the thinnest heterojunction, h-BN-C/G gives the highest conversion, which is eightfold higher than that of the mechanical mixture of graphene and boron nitride monolayers. h-BN-C/G exhibits a high turnover frequency value (4.0 mmol benzylamine g-1 h-1), which is 2.5-fold higher than that of the benchmark metal-free photocatalyst in the literature under even critical conditions.

20.
Chem Biol Interact ; 292: 110-120, 2018 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-30028964

RESUMO

Roxarsone is an organoarsenic feed additive used in livestock and poultry production that is released into the environment, where it poses a risk to human health. It is known to have a tumor-promoting effect that is brought about by pro-angiogenic factors such as vascular endothelial growth factor (VEGF) and it receptors (VEGFR). However, little information is available about the other signaling molecules that could be involved. This study aims to investigate the role of PLCγ/PKC signaling in roxarsone-induced angiogenesis in a mouse B16-F10 melanoma xenograft model and rat vascular endothelial cells (ECs). Results showed treatment with 5 mg/kg and 25 mg/kg roxarsone resulted in an obvious increase in the weight and volume of B16-F10 xenografts and PLCγ/PKC phosphorylation in a dose-dependent manner in C57BL/6 mice. SU5416, a VEGFR2 inhibitor, significantly attenuated the tumor growth induced by roxarsone. Further, 1.0 µmol/L roxarsone treatment in rat ECs was observed to significantly increase the optical density rate in the MTT assay, the number of BrdU-positive cells in the proliferation assay, the migration distance in the scratch test, and the number of meshes formed in the tube formation assay. In addition, treatment with 1.0 µmol/L roxarsone was associated with significantly higher phosphorylation of PLCγ/PKC than the control treatment. U73122, a PLCγ inhibitor, was found significantly to combat the effects of 1.0 µmol/L roxarsone on the ECs. Roxarsone is capable of promoting the growth of mouse B16-F10 xenografts and tube formation in vascular ECs. Moreover, VEGFR2/PLCγ/PKC signaling may play a regulatory role in in vivo and in vitro roxarsone-induced angiogenesis.


Assuntos
Neovascularização Patológica/fisiopatologia , Fosfolipase C gama/metabolismo , Proteína Quinase C/metabolismo , Roxarsona/toxicidade , Transdução de Sinais/efeitos dos fármacos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Western Blotting , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Mutagênicos/toxicidade , Neovascularização Patológica/induzido quimicamente
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA