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1.
Chem Commun (Camb) ; 59(10): 1369-1372, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36649108

RESUMO

We identified the contribution of -CF3 terminations to the Ti3C2Tx surface structure when ethanol and water were used as solvents during delamination through experimental and computational studies. Ethanol-treated -CF3-terminated Ti3C2Tx achieves better prevention of nanoflake aggregation, hydrophobicity, and small size, enabling enhanced capacitive properties in ionic liquid compared to water-treated Ti3C2Tx in aqueous and ionic liquid electrolytes.

2.
Nat Prod Res ; 36(8): 2028-2031, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33153305

RESUMO

A new alkaloid, tournesibirin (1), was isolated from the dichloromethane extracts from Tournefortia sibirica L. The structure of 1 was determined by spectroscopic methods, including UV, IR, HR-ESI-MS and extensive 1D and 2D NMR techniques.


Assuntos
Alcaloides , Boraginaceae , Alcaloides/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química
3.
Nat Prod Res ; 36(20): 5263-5267, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34030545

RESUMO

A new triterpenoid, named nigrumol A (1), along with 5 known triterpenoids were isolated from the aerial parts of Empetrum nigrum subsp. asiaticum (Nakai ex H.Ito) Kuvaev (E. nigrum) . The structure of 1 was elucidated by analysis of its spectroscopic data, including UV, IR, HR-ESI-MS and extensive 1 D and 2 D NMR techniques. Compound 1 showed that it could decrease ethanol-induced or CCl4-induced L02 cell toxicity effectively.[Formula: see text].


Assuntos
Ericaceae , Triterpenos , Ericaceae/química , Etanol , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Triterpenos/química , Triterpenos/farmacologia
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120247, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34399295

RESUMO

We developed a fluorescent probe, named 2-(4-(acryloyloxy) phenyl)-4-(2-carboxyphenyl)-7-(diethylamino) chromenylium (PA-A), for detecting Cys using the -OH protection/deprotection strategy, which can react with Cys to form a red-emitting anthocyanidin derivative fluorophore. The probe has high selectivity to Cys over Hcy and GSH in phosphate buffer solution (PBS, 10 mM, pH = 7.4), high sensitivity, a low detection limit of 4.48 × 10-8 mol/L, and it can be recognized with the naked eye. Fluorescence imaging experiment of Cys with PA-A at the cellular successfully showed excellent tissue penetration.


Assuntos
Cisteína , Corantes Fluorescentes , Glutationa , Células HeLa , Homocisteína , Humanos , Imagem Óptica
5.
Heliyon ; 6(8): e04436, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32793822

RESUMO

In present work, ordered mesoporous material SBA-15 was synthesized by using poly (alkylene oxide) block copolymer (Pluronic P123) as template and ethylsilicate as silica source in weak acid environment in a wide range of temperature. The focus of synthesis research was high hydrothermal temperature. The obtained products were characterized by various techniques, including XRD, N2 sorption isotherms, FTIR spectroscopy and thermogravimetric. The effect of hydrothermal temperature on the specific surface area, pore volume and pore size of SBA-15 products was investigated systematically. As the hydrothermal temperature increases from the 100-120 °C, the specific surface area and the pore volume of the mesoporous molecular sieve increase greatly. When the hydrothermal temperature increase further, the pore volume of the mesoporous molecular sieve increase continually. But the specific surface area decrease significantly. When the hydrothermal temperature is too high (over 140 °C), the order degree begins to decrease, So the specific surface area and pore volume decrease significantly because the pores structure have significant destruction and collapse. Mechanism and structural characteristics of P123 block copolymer could explain in detail the effect of hydrothermal temperature on the property and structure of mesoporous molecular sieve SBA-15.

6.
Nat Prod Res ; 34(13): 1862-1867, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30676077

RESUMO

Two new compounds, namely arteordoyn A (1) and arteordoyn B (2), together with four known compounds, were isolated from the petroleum ether extract of Artemisia ordosica Krasch. The structures elucidation of 1 and 2 were carried out by 1D-NMR (1H and 13C NMR), 2D-NMR (COSY, HSQC, HMBC and NOESY) and HR-ESI-MS spectral analysis.


Assuntos
Artemisia/química , Extratos Vegetais/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Polímero Poliacetilênico/química , Polímero Poliacetilênico/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray
7.
Nat Prod Res ; 34(21): 3061-3065, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31084212

RESUMO

Two new compounds, named ordosacid A (5) and ordosacid B (6), along with four known compounds: 3,4-dihydroxybenzaldehyde (1), p-hydroxybenzoic acid (2), p-hydroxycinnamic acid (3) and o-hydroxycinnamic acid (4), were isolated from the ethyl acetate extract of Artemisia ordosica Krasch. The structures of new compounds were elucidated on the basis of spectroscopic methods including UV, IR, ESI-MS, 1D NMR, 2D NMR, HR-ESI-MS and modified Mosher's method.


Assuntos
Artemisia/química , Produtos Biológicos/química , Artemisia/metabolismo , Produtos Biológicos/isolamento & purificação , China , Ácidos Cumáricos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Parabenos/química , Parabenos/isolamento & purificação , Extratos Vegetais/química , Propionatos/química , Propionatos/isolamento & purificação , Metabolismo Secundário , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Ultravioleta
8.
Z Naturforsch C J Biosci ; 74(9-10): 275-278, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31490779

RESUMO

A new compound, integracid (1), together with four known compounds were isolated from the dichloromethane (CH2Cl2) extract from Artemisia integrifolia L. The structures of compounds (1-5) were elucidated by spectroscopic methods, including ultraviolet, infrared (IR), high resolution-electrospray ionization-mass spectrometry (HR-ESI-MS) and extensive one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) techniques, and by comparison with data reported in the references. Antibacterial activities of the compounds were evaluated against various bacteria.


Assuntos
Anti-Infecciosos/química , Artemisia/química , Extratos Vegetais/química , Anti-Infecciosos/farmacologia , Bacillus cereus/efeitos dos fármacos , Extratos Vegetais/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Triterpenos/química , Triterpenos/farmacologia , Yersinia enterocolitica/efeitos dos fármacos
9.
Colloids Surf B Biointerfaces ; 181: 814-821, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31247406

RESUMO

A series of novel gemini pyridinium surfactants with different alkyl chains were synthesized and characterized. The surface properties and aggregation behavior of the gemini surfactants in solution were studied. The gemini pyridinium salts exhibit higher surface activity than quaternary ammonium salts and can form vesicles above critical micellization concentration (CMC). The antimicrobial performance of these surfactants against E. coli was investigated and compared with those of quaternary ammonium salts. Alkyl chain length has a significant effect on the antimicrobial activity of the gemini surfactants, and the surfactant with decyl group showed more effective antimicrobial activity than quaternary ammonium salts. The high cationic charge density on the polar head group and the strong adsorption tendency confer relatively high antimicrobial of the gemini surfactants.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Compostos de Piridínio/farmacologia , Tensoativos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Escherichia coli/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Estrutura Molecular , Tamanho da Partícula , Compostos de Piridínio/síntese química , Compostos de Piridínio/química , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/farmacologia , Propriedades de Superfície , Tensoativos/síntese química , Tensoativos/química
11.
Biomed Pharmacother ; 99: 859-866, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29710485

RESUMO

Type 2 diabetes mellitus (T2DM) promotes a high oxidative stress and hypercoagulable state that drives microvascular injury and multiple-organ abnormality. Elevated thrombin activity underlies T2DM-linked endothelial dysfunction, but the mechanistic links between T2DM/oxidative stress axis and thrombin-associated endothelial pathologies are incompletely understood. In this work, immunohistochemical studies and quantitative analysis using isolated endothelial cells (ECs) identified accumulated Kru¨ppel-like family of transcription factor 14 (KLF14) deposits in ECs from multiple organs as distinct features of T2DM mice. KLF14 upregulation in ECs, which was stimulated by thrombin treatment, was dependent on multiple pathways including calcium mobilization, activation of PKC and AMPK pathways. Functionally, inhibition of endogenous KLF14 expression significantly attenuated thrombin-induced endotheliocyte proliferation, endothelial cell migration and oxidative stress. Molecularly, by directly binding the promoter, KLF14 functions as a transcriptional activator of PLK1, a polo-like kinase whose overexpression induced excessive reactive oxygen species (ROS) production. Transient knockdown of PLK1 was sufficient to suppress KLF14 overexpression-potentiated endothelial dysfunction. Collectively, these data provide proof of concept that deregulation of KLF14/PLK1 cascade plays a key role in thrombin-induced endothelial dysfunction and targeting KLF14 or PLK1 may limit thrombin-associated pathologies in T2DM patients.


Assuntos
Proteínas de Ciclo Celular/genética , Diabetes Mellitus Experimental/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Fatores de Transcrição Kruppel-Like/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Animais , Movimento Celular/genética , Proliferação de Células/genética , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Tipo 2/genética , Células Endoteliais/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Trombina/metabolismo , Quinase 1 Polo-Like
12.
Cell Prolif ; 48(6): 643-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26597380

RESUMO

OBJECTIVES: miRNAs play crucial roles in human tumourigenesis. This study was performed to measure expression and function of miR-762 in breast cancer. MATERIALS AND METHODS: Expression of miR-762 in breast tissues and cell lines (SK-BR-3, DA-MB-435s, MCF-7 and MDA-MB-231, HBL-100) was measured by using real-time RT-PCR. We restored expression of miR-762 in MCF-7 cells to measure its functional roles. Luciferase assays were performed to reveal the target gene of miR-762. RESULTS: Expression of miR-762 was high in both breast cancer cell lines and specimens, and its overexpression increased breast cancer cell proliferation and invasion. Interferon regulatory factor 7 (IRF7) is a direct target of miR-762 and overexpression of miR-762 reduced expression of IRF7. Moreover, IRF7 was repressed, its levels inversely correlated to miR-762 expression. IRF7 rescued miR-762-induced cell invasion and proliferation. CONCLUSIONS: These results demonstrate that miR-762 tumour effect was achieved by targeting IRF7 in human breast cancer specimens.


Assuntos
Neoplasias da Mama/genética , Fator Regulador 7 de Interferon/biossíntese , MicroRNAs/genética , Invasividade Neoplásica/genética , Metástase Neoplásica/genética , Neoplasias da Mama/patologia , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , MicroRNAs/biossíntese , Invasividade Neoplásica/patologia , Metástase Neoplásica/patologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-24845874

RESUMO

A new compound based on 2-quinolinone derivative with very little side effects on organisms, 3-(1H-benzo[d]imidazol-2-yl)-6,7-difluoroquinolin-2(1H)-one, has been designed, synthesized and characterized. And its recognition ability was firstly studied by spectroscopy. The result indicated that the compound shows high selectivity for Hg2+ over other metal ions with detectable fluorescent signals in aqueous-methanol media. The proposed mechanism is that the fluorescence of the probe was quenched due to the effect from spin-orbit coupling of Hg2+ after the probe coordinated with Hg2+, and was proved by ESI-MS and 1H NMR analysis.


Assuntos
Mercúrio/química , Quinolonas/química , Calibragem , Concentração de Íons de Hidrogênio , Íons , Limite de Detecção , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
14.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 4): m469, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21753984

RESUMO

The title compound, [Ni(C(15)H(24)NSi)(2)], is a homoleptic metal-η(3)-aza-allyl centrosymmetric complex containing two aza-allyl ligands bound in an η(3)-manner to an Ni(II) atom located on a center of symmetry. The overall coordination about the Ni(II) atom is square-planar. The C and N atoms of the aza-allyl group are sp(2)-hybridized. The uneven Ni-C and Ni-N distances [2.045 (5)/2.060 (6) and 1.916 (5) Å] are influenced by a steric hindering effect from the nearby benzene ring.

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