Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Appl Biochem Biotechnol ; 196(1): 588-603, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37162682

RESUMO

N6-Methyladenosine (m6A) mRNA methylation modification is regarded as an important mechanism involved in diverse physiological processes. YT521-B homology (YTH) domain family members are associated with the tumorigenesis of several cancers. However, the role of YTHDC2 in papillary thyroid cancer (PTC) progression remains unknown. Results showed that YTHDC1, YTHDF1, YTHDF2, and YTHDF3 showed no observable difference in thyroid cancer samples. YTHDC2 was significantly downregulated in thyroid cancer samples and cells. YTHDC2 inhibited cell proliferation in PTC cells. YTHDC2 elicited apoptosis in PTC cells, as demonstrated by the elevated expression of pro-apoptotic factors cl-caspase-3/caspase-3 and Bcl-2-associated (Bax), and the reduced anti-apoptotic B cell lymphoma-2 (Bcl-2) expression. There was a positive correlation between YTHDC2 and cylindromatosis (CYLD) expression based on GEPIA database. YTHDC2 increased CYLD expression in PTC cells. CYLD knockdown abolished the effects of YTHDC2 on PTC cell proliferation and apoptosis. Additionally, YTHDC2 inactivated the protein kinase B (Akt) pathway by increasing CYLD in PTC cells. Overall, YTHDC2 inhibited cell proliferation and induced apoptosis in PTC cells by regulating CYLD-mediated inactivation of Akt pathway.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Caspase 3/metabolismo , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Proliferação de Células/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Apoptose/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Enzima Desubiquitinante CYLD/genética , Enzima Desubiquitinante CYLD/metabolismo , RNA Helicases
2.
Chemistry ; 29(32): e202300522, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-36912574

RESUMO

The electroreduction of carbon dioxide (CO2 ) is a sustainable method for generating valuable chemicals; however, avoiding unwanted hydrogen (H2 ) production during the electrolysis is a major challenge. Coproduction of carbon monoxide (CO) and H2 to produce syngas is an effective strategy for solving this problem, and syngas with a desired CO/H2 ratio can be employed to produce methanol or other valuable chemicals. Herein, a series of palladium-bismuth (Pd-Bi) bimetallic nanochains with different Pd/Bi atomic ratios were prepared and used in the electroreduction of CO2 to syngas in ionic liquid-based electrolytes. The ratio of CO/H2 in syngas was regulated in a wide range from 1 : 7 to 9 : 1 by controlling the applied potentials, Pd/Bi atomic ratios and composition of the electrolytes. In particular, the current density reached 19.3 mA cm-2 on Pd3 Bi bimetallic nanochains at an applied potential of -2.3 V versus Ag/Ag+ when the CO/H2 ratio was approximately 1 : 1. Moreover, the maximum CO Faradaic efficiency was 87.7 % for these electrocatalysts at an applied potential of -2.0 V versus Ag/Ag+ . The synergistic effect of Pd and Bi in the ionic liquid-based electrolyte was the primary reason for the distinct electrocatalytic efficiency of the Pd3 Bi bimetallic nanochains. The incorporation of moderate amounts of Bi into the Pd lattice resulted in a stronger CO2 adsorption capacity, more active sites and faster electron transfer rate, which are conducive to improving the electrocatalytic activity.


Assuntos
Bismuto , Líquidos Iônicos , Dióxido de Carbono , Paládio , Eletrólitos
3.
RSC Adv ; 13(7): 4612-4622, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36760310

RESUMO

In this work, we use density functional theory (DFT) calculated competitive hydrogen bonds and dissipative particle dynamics (DPD) simulated micellar structural information to uncover the CO2-expanded liquid (CXL)-aided self-assembled structure and emission mechanisms of the self-assembled fluorescent composites (SAFCs). Herein, the SAFCs are formed through the self assembly between diblock copolymer polystyrene-b-poly(4-vinylpyridine) (PS-b-P4VP) blend and the dye molecule 4-(9-(2-(4-hydroxyphenyl)ethynyl)-7,10-diphenylfluoranthen-8-yl)phenol (4) in CO2-expanded toluene at 313.2 K and varied pressures. Firstly, from DPD simulation, we have demonstrated that the addition of CO2 to toluene favors both the expansion of the solvophobic P4VP phase and contraction of solvophilic PS chains, which facilitates the continuous morphological transitions of SAFCs from spherical micelles (3.0 MPa) through wormlike plus spherical micelles (4.0-4.8 MPa) to large vesicles (6.0-6.5 MPa) with pressure rise. Secondly, the DFT calculated bonding energies and IR spectra of the competitive hydrogen bonds help us to clarify the major type of hydrogen bonds determining the fluorescence (FL) performance of the SAFCs. Furthermore, we have revealed the SAFC emission mechanism via the pressure-tunable changes in the aggregation degrees and amount of hydrogen bonds involving 4 and P4VP chains. This work provides a good understanding for the morphology-property control of the self-assembled polymer composites in both microscopic and mesoscopic scales.

4.
J Hazard Mater ; 434: 128896, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35439698

RESUMO

Paper products are widely used in daily life, while the lack of antibacterial activity has made them become some disease transmission media. Herein, we introduced NIR-responsive molybdenum disulfide nanosheets (MoS2) to endow nanocellulose paper antibacterial activity by electrostatic self-assembly with quaternized chitosan (QCS). Firstly, the MoS2 nanosheets were exfoliated and stabilized with QCS under ultrasonication. The strong coordination between QCS and MoS2 as well as the electrostatic attraction between QCS and cellulose nanofiber (CNF) helped to fabricate the MoS2@QCS/CNF composite paper. The MoS2@QCS/CNF composite paper exhibited excellent photothermal and photodynamic activity, achieving over 99.9% antibacterial efficacy against both E. coli and S. aureus, respectively. The hyperthermia induced by MoS2 accelerated the glutathione (GSH) consumption and the reactive oxygen species (ROS)-independent oxidative stress destroyed the bacteria membranes integrity, synergistically leading to the malondialdehyde (MDA) oxidation and protein leakage to inhibit the bacteria growth. Importantly, the self-assembled fibrous network incorporating with the photo-stable antibacterial MoS2 enabled the flexible composite paper with excellent mechanical strength and recyclability for long-term antimicrobial, possessing over 99.9% inhibition even after five cycles. No cell cytotoxicity was observed for the MoS2@QCS/CNF composite paper, suggesting the potential of composite paper for bacterial infection control.


Assuntos
Quitosana , Antibacterianos/farmacologia , Bactérias , Celulose , Quitosana/farmacologia , Dissulfetos/farmacologia , Escherichia coli , Molibdênio/farmacologia , Staphylococcus aureus
5.
Sci Total Environ ; 764: 142813, 2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33097246

RESUMO

Exploiting the full potential of copper-based nanoparticles in the activation of peroxymonopersulfate (PMS) is a great challenge due to their insufficient dispersity and electronic properties. We report here a novel iron­nitrogen co-doped carbon nanotube (FNC) modified with a Cu2O nanocomposite (Cu2O/FNC) that exhibits ultrahigh catalytic performance in the activation of PMS to degrade fluconazole (~95%). Catalytic performance evaluation illustrated that Cu2O/FNC also has wide pH applicability (3.0-11.0), long-term stability and excellent adaptability. In addition, luminescent bacteria toxicity tests confirm that Cu2O/FNC/PMS significantly reduced the acute biotoxicity of various recalcitrant pollutants (reduced by 45-83%). By identifying the reactive oxygen species (ROS) and catalytic performance for various pollutants, we propose that pollutants that interact weekly with activators are mostly destroyed by sulfate radicals and hydroxyl radicals, whilst both radical and non-radical routes were involved in the degradation of pollutants that were easily adsorbed. By modifying Cu2O with FNC, several crucial properties such as the specific surface area, surface defects, active sites and the charge transfer rate were significantly improved, leading to excellent catalytic performance for pollutant removal. Finally, a reasonable reaction mechanism is advanced for the fluconazole degradation pathway. This study not only develops a novel PMS oxidation system for fluconazole degradation, but also provides a new strategy to improve the reactivity and applicability of PMS activators by combining radical and non-radical activation pathways.


Assuntos
Ferro , Nanotubos de Carbono , Eletrônica , Nitrogênio , Peróxidos
6.
Environ Sci Technol ; 52(8): 4754-4762, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29547691

RESUMO

The conventional flue gas treatment technologies require high capital investments and chemical costs, which limit their application in industrial sectors. This study developed a sulfur-cycling technology to integrate sulfide production by biological sulfur reduction and simultaneous catalytic desulfurization and denitrification with H2S (H2S-SCDD) for flue gas treatment and sulfur recovery. In a packed bed reactor, high-rate sulfide production (1.63 ± 0.16 kg S/m3-d) from biological sulfur reduction was achieved using organics in wastewater as electron donors at pH around 5.8. 93% of sulfide in wastewater was stripped out as H2Sg, which can be a low-cost reducing agent in the H2S-SCDD process. Over 90% of both SO2 and NO were removed by the H2S-SCDD process under the test conditions, resulting in the formation of sulfur. 88% of the input S (H2Sg and SO2) were recovered as octasulfur with high purity. Besides partial recycling to produce biogenic sulfide, excessive sulfur can be obtained as a sellable product. The integrated sulfur-cycling technology is a chemical-saving and even profitable solution to the flue gas treatment in industrial sectors with wastewater available.


Assuntos
Substâncias Redutoras , Enxofre , Catálise , Desnitrificação , Águas Residuárias
7.
J Transl Med ; 12: 344, 2014 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-25475342

RESUMO

BACKGROUND: Endometrial regenerative cells (ERCs) are mesenchymal-like stem cells that can be non-invasively obtained from menstrual blood and are easily grown /generated at a large scale without tumorigenesis. We previously reported that ERCs exhibit unique immunoregulatory properties in vitro, however their immunosuppressive potential in protecting the colon from colitis has not been investigated. The present study was undertaken to determine the efficacy of ERCs in mediating immunomodulatory functions against colitis. METHODS: Colitis was induced by 4% dextran-sulfate-sodium (DSS, in drinking water) in BALB/c mice for 7 days. ERCs were cultured from healthy female menstrual blood, and injected (1 million/mouse/day, i.v.) into mice on days 2, 5, and 8 following colitis induction. Colonic and splenic tissues were collected on day 14 post-DSS-induction. Clinical signs, disease activity index (DAI), pathological and immunohistological changes, cytokine profiles and cell populations were evaluated. RESULTS: DSS-induced mice in untreated group developed severe colitis, characterized by body-weight loss, bloody stool, diarrhea, mucosal ulceration and colon shortening, as well as pathological changes of intra-colon cell infiltrations of neutrophils and Mac-1 positive cells. Notably, ERCs attenuated colitis with significantly reduced DAI, decreased levels of intra-colon IL-2 and TNF-α, but increased expressions of IL-4 and IL-10. Compared with those of untreated colitis mice, splenic dendritic cells isolated from ERC-treated mice exhibited significantly decreased MHC-II expression. ERC-treated mice also demonstrated much less CD3(+)CD25(+) active T cell and CD3(+)CD8(+) T cell population and significantly higher level of CD4(+)CD25(+)Foxp3(+) Treg cells. CONCLUSIONS: This study demonstrated novel anti-inflammatory and immunosuppressive effects of ERCs in attenuating colitis in mice, and suggested that the unique features of ERCs make them a promising therapeutic tool for the treatment of ulcerative colitis.


Assuntos
Colite/terapia , Endométrio/citologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Animais , Colite/induzido quimicamente , Citocinas/genética , Sulfato de Dextrana/administração & dosagem , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Transcrição Gênica
8.
ScientificWorldJournal ; 2014: 647040, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24558321

RESUMO

This study was conducted to synthesize a series of nanosized BiOI-TiO2 catalysts to photodegrade Bisphenol A solution. The BiOI-TiO2 nanoparticles were synthesized in the reverse microemulsions, consisting of cyclohexane, Triton X-100, n-hexanol, and aqueous salt solutions. The synthesized particles were characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) surface analyzer, Fourier transform-infrared spectroscopy (FT-IR), ultraviolet-visible light (UV-Vis) absorption spectra and transmission electron microscope (TEM). The photodegradation of Bisphenol A (BPA) in aqueous suspension under visible light irradiation was investigated to explore the feasibility of using the photocatalytic method to treat BPA wastewater. The effects of different molar ratios of BiOI to TiO2 on the photocatalytic activity were discussed. The experimental results revealed that the photocatalytic effect of the BiOI-TiO2 particles was superior to the commercial P25 TiO2. The BPA degradation could be approached by a pseudo-first-order rate expression. The observed reaction rate constant (kobs) was related to nanoparticles dosage and initial solution pH.


Assuntos
Bismuto/química , Técnicas de Química Sintética/métodos , Nanopartículas Metálicas/química , Fotoquímica/métodos , Titânio/química , Catálise , Emulsões , Difração de Raios X/métodos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA