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1.
J Cell Mol Med ; 27(22): 3431-3442, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37596794

RESUMEN

The high rates of misdiagnosis and untreated mortality with regard to Budd-Chiari syndrome (BCS) indicated the need to screen effective biomarkers. The aim of this study was to explore the function of extracellular vesicles (EVs) in patients with BCS as well as associated mechanisms. First, differentially expressed long non-coding RNAs (lncRNAs) from EVs separated from serum between BCS and healthy controls were screened using microarray analysis. Second, the proliferation, migration and tube formation of human vascular endothelial cells (HUVECs) were detected after EVs treatment, along with vascular endothelial growth factor (VEGF) levels and inflammatory factors from the cell supernatant. Last, the overexpressed lncRNA was transfected into the cells to further explore the mechanisms involved. Extracellular vesicles of BCS patients have significantly higher levels of lncRNA MTUS2-5 than healthy controls. Apparently, treatment with EVs from BCS or the ones transfected with plasmids that overexpress lncRNA MTUS2-5 enhances proliferation, migration and angiogenesis capacity. The results were considerably better than those obtained from treatment with EVs from healthy controls or transfection with the normal control plasmid, which also elevated the level of VEGF and inflammatory factors. Furthermore, FOS and PTGS2 were potentially regulated by the lncRNA MTUS2-5 transmitted by EVs. The lncRNA MTUS2-5 in EVs plays an important role in angiogenesis in the Budd-Chiari syndrome.


Asunto(s)
Síndrome de Budd-Chiari , Vesículas Extracelulares , ARN Largo no Codificante , Humanos , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Células Endoteliales/metabolismo , Síndrome de Budd-Chiari/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , Neovascularización Patológica/metabolismo , Proliferación Celular/genética
2.
ACS Appl Mater Interfaces ; 15(25): 30913-30923, 2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37335981

RESUMEN

To improve the lithium-ion transporting ability in lithium-ion batteries, a high-performance polyimide-based lithium-ion battery separator (PI-mod) was prepared by chemically grafting poly(ethylene glycol) (PEG) onto the surface of a heat-resistant polyimide nanofiber matrix with the assistance of amino-rich polyethyleneimine (PEI). The resulted PEI-PEG polymer coating exhibited unique gel-like properties with an electrolyte uptake rate of 168%, an area resistance as low as 2.60 Ω·cm2, and an ionic conductivity up to 2.33 mS·cm-1, which are 3.5, 0.10, and 12.3 times that of the commercial separator Celgard 2320, respectively. Meanwhile, the heat-resistant polyimide skeleton can effectively avoid thermal shrinkage of the modified separator even after 200 °C treatment for 0.5 h, which ensures the safety of the battery working under extreme conditions. The modified PI separator possessed a high electrochemical stability window of 4.5 V. Compared with the batteries from the commercial separator Celgard 2320 and the pure polyimide matrix, the assembled coin cell with the PI-mod separator showed much better rate capabilities and capacity retention due to the high electrolyte affinity of the PEI-PEG polymer coating. The developed strategy of using the electrolyte-swollen polymer to modify the thermal-resistant separator network provides an efficient way for establishing high-power lithium-ion batteries with good safety performance.

3.
Rev Sci Instrum ; 92(2): 025124, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33648065

RESUMEN

The background noise (BGN) of test equipment affects the lower detection limit of the measurement range, and achieving an ultralow BGN is identified as a formidable challenge for highly accurate testing of a free-standing film. In this paper, a new gas transmission rate test apparatus is designed by detecting the electrical resistance increase with calcium corrosion. Thanks to the new design strategy, the only permeable place of this apparatus is the clamping and holding site. Mathematical methods for calculating the molecular permeation behaviors and magnitude of BGN are devised. The results show that the properties and structures of the materials significantly affect the BGN value. By using a sealant with low permeability (2.25 × 10-15 g cm cm-2 s-1 Pa-1) and a clamping ring with small width (2.5 mm) and testing an ultrahigh barrier (WVTR: 10-6 g m-2 day-1), the BGN could reach a level of 10-11 g m-2 day-1. With theoretical guidance, after optimization, one sealing structure obtained an ultralow BGN value (∼10-6 g m-2 day-1) in the actual test. The electrical resistance test has many advantages over existing methods. Additionally, the computational method devised in this study to examine the effects of materials provides a useful tool to achieve high-accuracy testing.

4.
Angew Chem Int Ed Engl ; 60(13): 7220-7226, 2021 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-33448116

RESUMEN

A series of rigid nonconjugated polyimide (PI)-based thermally activated delayed fluorescence (TADF) polymers were reported for the first time, based on a "TADF-Linker-Host" strategy. Among of which, the TADF unit contains a typical TADF luminous core structure, the "Host" unit exhibits effective conjugation length that endows polyimide with high triplet energy, and the "Linker" unit has an aliphatic ring structure to improve solubility and inhibits intramolecular charge transfer effect. All the TADF polymers exhibit high thermal stability (Tg >308.7 °C) and refractive index (1.76-1.79). Remarkably, highly-efficient polymer light-emitting diodes (PLEDs) based on the polymers are successfully realized, leading to a maximal external quantum efficiency of 21.0 % along with low efficiency roll-off. Such outstanding efficiency is amongst the state-of-the-art performance of nonconjugated PLEDs, confirming the effectiveness of structural design strategy, providing helpful and valuable guidance on the development of highly-efficient fluorescent polymer materials and PLEDs.

5.
ACS Appl Mater Interfaces ; 12(30): 34198-34207, 2020 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-32594733

RESUMEN

Luminophores usually suffer from luminescent quenching when introduced into a polymer backbone or side chain, which leads to the inefficient luminescence or even no luminescence of the polymer. In this work, alicyclic imide rings were found to be capable of balancing the donor-acceptor properties between the rigid spacer and the aggregation-induced emission-active fluorophore in light-emitting polymers. Along with the nonplanar and rigid emitter, the suppressed intramolecular charge-transfer effect and interchain disturbance can efficiently preserve the luminescence characteristics of the active center, resulting in high solid-state photoluminescence quantum yields of up to 89%. The amorphous polyimides exhibit excellent thermal properties, such as high glass transition temperature (Tg) values (398 °C) and high thermal decomposition temperature (Td) values (538 °C). As far as we know, these luminescent polymer materials are of excellent heat resistance with the highest luminescence efficiency reported. The results have significant impact for the precise prediction of the optical properties of light-emitting polymers by appropriate monomer design, providing controllable ways for synthesizing high thermal stability polymeric materials with efficient fluorescence properties.

6.
Micromachines (Basel) ; 10(12)2019 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-31835484

RESUMEN

Wearable sensing technologies have been developed rapidly in the last decades for physiological and biomechanical signal monitoring. Much attention has been paid to functions of wearable applications, but comfort parameters have been overlooked. This research presents a developed fabric temperature sensor by adopting fiber Bragg grating (FBG) sensors and processing via a textile platform. This FBG-based quasi-distributed sensing system demonstrated a sensitivity of 10.61 ± 0.08 pm/°C with high stability in various temperature environments. No obvious wavelength shift occurred under the curvatures varying from 0 to 50.48 m-1 and in different integration methods with textiles. The temperature distribution monitored by the developed textile sensor in a complex environment with multiple heat sources was deduced using MATLAB to present a real-time dynamic temperature distribution in the wearing environment. This novel fabric temperature sensor shows high sensitivity, stability, and usability with comfort textile properties that are of great potential in wearable applications.

8.
Chem Biodivers ; 10(3): 367-84, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23495154

RESUMEN

To investigate the relationship between the molecular structure and biological activity of polypyridyl Ru(II) complexes, such as DNA binding, photocleavage ability, and DNA topoisomerase and RNA polymerase inhibition, six new [Ru(bpy)(2)(dppz)](2+) (bpy=2,2'-bipyridine; dppz=dipyrido[3,2-a:2,',3'-c]phenazine) analogs have been synthesized and characterized by means of (1)H-NMR spectroscopy, mass spectrometry, and elemental analysis. Interestingly, the biological properties of these complexes have been identified to be quite different via a series of experimental methods, such as spectral titration, DNA thermal denaturation, viscosity, and gel electrophoresis. To explain the experimental regularity and reveal the underlying mechanism of biological activity, the properties of energy levels and population of frontier molecular orbitals and excited-state transitions of these complexes have been studied by density-functional theory (DFT) and time-depended DFT (TDDFT) calculations. The results suggest that DNA intercalative ligands with better planarity, greater hydrophobicity, and less steric hindrance are beneficial to the DNA intercalation and enzymatic inhibition of their complexes.


Asunto(s)
Complejos de Coordinación/química , ADN-Topoisomerasas de Tipo I/química , ARN Polimerasas Dirigidas por ADN/antagonistas & inhibidores , ADN/metabolismo , Sustancias Intercalantes/química , Rutenio/química , Inhibidores de Topoisomerasa I/química , 2,2'-Dipiridil/química , Animales , Bovinos , Complejos de Coordinación/síntesis química , ADN/química , ADN-Topoisomerasas de Tipo I/metabolismo , ARN Polimerasas Dirigidas por ADN/metabolismo , Sustancias Intercalantes/síntesis química , Fotólisis , Teoría Cuántica , Relación Estructura-Actividad , Inhibidores de Topoisomerasa I/síntesis química
9.
J Inorg Biochem ; 104(5): 576-82, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20167375

RESUMEN

To explore the structure-activity relationship of polypyridyl ruthenium(II) complexes as topoisomerase II and T7 RNA polymerase inhibitors, four new complexes, [Ru(4dmb)(2)(ppd)](2+) (4dmb=4,4'-dimethyl-2,2'-bipyridine, ppd=pteridino[6,7-f][1,10] phenanthroline-1,13(10H,12H)-dione), [Ru(5dmb)(2)(ppd)](2+) (5dmb=5,5'-dimethyl-2,2'-bipyridine), [Ru(dip)(2)(ppd)](2+) (dip=4,7-diphenyl-1,10-phenanthroline), and [Ru(ip)(2)(ppd)](2+) (ip=imidazole[4,5-f][1,10]phenanthroline) have been synthesized and characterized in detail by (1)H NMR spectroscopy, mass spectrometry and elemental analysis. Their interaction with calf thymus DNA and the inhibitory activity towards topoisomerase II and T7 RNA polymerase were investigated. The results suggest that although all of these four Ru(II) complexes are potent DNA intercalators, topoisomerase II inhibitors and DNA transcription inhibitors, their DNA binding strength and inhibitory activities are quite different. The activity of ip- and dip-complexes are significantly higher than the dmb-complexes. To explain the experimental regularity and reveal the underlying quantum chemistry mechanism of the biological activity, the properties of energy levels and population of frontier molecular orbitals and excited state transitions of these complexes have been studied by density functional theory (DFT) and time-depended DFT (TDDFT) calculations. The results suggest that ancillary ligands bearing lower energy of the lowest unoccupied molecular orbitals (LUMOs), better hydrophobicity and less steric hindrance of are beneficial to the DNA intercalation and topoisomerase II and DNA transcription inhibition of their complexes.


Asunto(s)
ADN-Topoisomerasas de Tipo II , Compuestos de Rutenio , Transcripción Genética , Animales , Bovinos , ADN/química , ADN/genética , ADN/metabolismo , ADN-Topoisomerasas de Tipo II/química , ADN-Topoisomerasas de Tipo II/metabolismo , ARN Polimerasas Dirigidas por ADN/antagonistas & inhibidores , ARN Polimerasas Dirigidas por ADN/química , ARN Polimerasas Dirigidas por ADN/metabolismo , Humanos , Ligandos , Estructura Molecular , Desnaturalización de Ácido Nucleico , Compuestos de Rutenio/química , Compuestos de Rutenio/metabolismo , Relación Estructura-Actividad , Inhibidores de Topoisomerasa II , Proteínas Virales/antagonistas & inhibidores , Proteínas Virales/química , Proteínas Virales/metabolismo
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