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2.
Comput Intell Neurosci ; 2022: 5932512, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36210981

RESUMEN

Background: Gastric cancer (GC) is a primary cause of cancer death around the world. Previous studies have found that Drosha plays a significant role in the development of tumor cells. Soon after, we unexpectedly found that the expression of microRNA6778-5p (miR6778-5p) is unconventionally high in the gastric cancer cells low-expressing Drosha. So, we designed the Drosha interference sequence and recombined it into a lentiviral vector to construct Drosha knockdown lentivirus and transfected the Drosha knockdown lentivirus into gastric cancer cells to establish Drosha knockdown gastric cancer cell lines. We aimed to explore the effect of microRNA6778-5p on the proliferation of gastric cancer cells with Drosha knockdown and its intrinsic mechanism. Methods: We designed the Drosha interference sequence and recombined it into a lentiviral vector to construct Drosha knockdown lentivirus and transfected the Drosha knockdown lentivirus into gastric cancer cells to establish Drosha knockdown gastric cancer cell lines. After transfecting miR6778-5p mimics and inhibitor into gastric cancer cell lines with Drosha knockdown, the expression levels of miR6778-5p mimics in Drosha low-expressing gastric cancer cells increased, while miR6778-5p inhibitor decreased the expression levels of miR6778-5p. The Cell Counting Kit-8 (CCK-8) experiment was used to detect the proliferation ability of gastric cancer cells after overexpression or knockdown of miR6778-5p and bioinformatics predicted the relationship between miR6778-5p and glycogen synthase kinase-3ß (GSK3ß). Results: After infection with the Drosha knockdown lentivirus, Drosha's mRNA and protein levels were significantly downregulated in gastric cancer cells. The expression levels of miR6778-5p mimics in Drosha low-expressing gastric cancer cells increased, while miR6778-5p inhibitor decreased the expression levels of miR6778-5p. Overexpression of miR6778-5p significantly enhanced the proliferation ability of Drosha low-expression gastric cancer cells; on the contrary, knocking down miR6778-5p weakened the proliferation ability of Drosha low-expression gastric cancer cells. Bioinformatics predicted that miR6778-5p targeted glycogen synthase kinase-3ß (GSK3ß) and the mRNA and protein levels of GSK3ß decreased significantly after overexpression of miR6778-5p. Conclusion: miR6778-5p promotes the proliferation of Drosha low-expressing gastric cancer cells by targeting GSK3ß.


Asunto(s)
MicroARNs , Neoplasias Gástricas , Línea Celular Tumoral , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Glucógeno Sintasa Quinasa 3 beta/genética , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Humanos , MicroARNs/genética , MicroARNs/metabolismo , ARN Mensajero/genética , Ribonucleasa III/genética , Ribonucleasa III/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología
3.
ACS Omega ; 6(39): 25329-25337, 2021 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-34632191

RESUMEN

Based on the advantages of intrinsic safety, flexibility, and good interfacial contact with electrodes, a gel polymer electrolyte (GPE) is a promising electrolyte for lithium-ion batteries, compared with the conventional liquid electrolyte. However, the unstable electrochemical performance and the liquid state in a microscale limit the commercial application of GPE. Herein, we developed a novel gel polymer electrolyte for lithium-ion batteries by blending methyl methacrylate (MMA), N-butyl-N-methyl-piperidinium (Pyr14TFSI), and lithium salts in a solvent-free procedure, with SiO2 and Li0.33La0.56TiO3 (LLTO) additives. The prepared MMA-Pyr14TFSI-3 wt % LLTO electrolyte shows the best electrochemical performance and obtains a high ion conductivity of 4.51 × 10-3 S cm-1 at a temperature of 60 °C. Notably, the electrochemical window could be stable up to 5.0 V vs Li+/Li. Moreover, the batteries with the GPE also show excellent electrochemical performance. In the LiFePO4/MMA-Pyr14TFSI-3 wt % LLTO/Li cell, a high initial discharge capacity was achieved 150 mA h g-1 at 0.5C with a Coulombic efficiency over 99% and maintaining a good capacity retention of 90.7% after 100 cycles at 0.5C under 60 °C. In addition, the physical properties of the GPE have been investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) measurements, Fourier transform infrared (FTIR) spectroscopy, and thermogravimetry (TG).

4.
Carbohydr Polym ; 241: 116372, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32507194

RESUMEN

A series of amylose phenylcarbamate derivatives bearing different chloro- or/and methyl- substituents on the phenyl groups were synthesized and their enantioseparation properties were examined by high-performance liquid chromatography. The enantioseparation power considerably altered due to the substituents on the phenyl units. The amylose derivative bearing 3-chloro-5-methyl disubstituents seemed to possess much higher chiral resolution power. The introduction of both an electron-withdrawing chloro and an electron-donating methyl groups enabled the NH groups to contain a moderate acidity, which may be important to construct a regular secondary structure for the amylose phenylcarbamates. Some interesting observations in 1H NMR and circular dichroism spectroscopy demonstrated the correlations between the structure and enantioseparation ability. The electronegativity, location and amount of the substituents at the phenyl residues have great influence on the enantioseparation power of the amylose derivatives. The mechanism involved in enantioselective discrimination of the amylose phenylcarbamates was further investigated by the molecular docking simulation.

5.
ACS Omega ; 5(22): 13185-13195, 2020 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-32548505

RESUMEN

Photocatalytic technology aiming to eliminate organic pollutants in water has been rapidly developed. In this work, we successfully synthesized CuWO4/ZnO photocatalysts with different weight ratios of CuWO4 through facile hydrothermal treatment. Crystal structures, forms, and optical properties of these as-prepared materials were investigated and analyzed. 3% CuWO4/ZnO showed the optimum photodegradation efficiency toward methylene blue under the irradiation of simulated sunlight for 120 min, the degradation rate of which was 98.9%. The pseudo-first-order rate constant of 3% CuWO4/ZnO was ∼11.3 and ∼3.5 times bigger than that of pristine CuWO4 and ZnO, respectively. Furthermore, the material exhibited high stability and reusability after five consecutive photocatalytic tests. In addition, free radical capture experiments were conducted and the possible mechanism proposed explained that the synergistic effect between CuWO4 and ZnO accelerates the photodegradation reaction. This work provides a feasible technical background for the efficient and sustainable utilization of photocatalysts in wastewater control.

6.
Carbohydr Polym ; 218: 30-36, 2019 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-31221334

RESUMEN

Seven amylose derivatives bearing two regioselective carbamate pendants at 2,3- and 6-positions of a glucose unit were synthesized through protection and deprotection at the 6-position. The chiral recognition abilities of the obtained derivatives were evaluated as the chiral stationary phases (CSPs) for high-performance liquid chromatography (HPLC). Each derivative had its own characteristic recognition ability depending on the arrangement of carbamate pendants at the three positions. The nature, position and number of the substituents on the aromatic moieties of pendants play a significant role on the chiral recognition ability of these derivatives. Most amylose derivatives exhibit good enantioselectivity for the racemates in this study, and those bearing electron-withdrawing para-chlorophenylcarbamates at 2- and 3-positions possessed relatively better chiral recognition than others. Some racemates could be better resolved on the amylose derivatives with different pendants than on Chiralpak AD, one of the most powerful commercially available chiral columns derived from amylose tris(3,5-dimethylphenylcarbamate).

7.
J Chromatogr A ; 1572: 54-61, 2018 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-30146373

RESUMEN

Nine cellulose derivatives bearing two different carbamate substituents at 2,3- and 6-positions of a glucose unit were synthesized by a sequential process based on the regioselective protection at 6-position. Their chiral recognition abilities were then evaluated as the chiral stationary phases (CSPs) for high-performance liquid chromatography (HPLC) after coating them onto the macroporous silica gel. The introduction of two different phenylcarbamates at 2,3- and 6-positions of glucose unit was comparatively more attractive than that of one phenylcarbamate and one cyclohexylcarbamate to enhance the chiral recognition ability of these cellulose derivatives. Different combination of carbamate substituents of cellulose derivatives seems to offer superior resolution of different racemic compounds. The chiral recognition ability of these derivatives is apparently dependent on the nature, position and number of the substituents on the aromatic moieties. Many derivatives exhibit good enantioselectivity for the racemates in this study, and those based on cellulose 2,3-(3,5-dimethylphenylcarbamate) showed relatively better chiral recognition than others. Some racemates could be even more efficiently resolved on the cellulose derivatives with different carbamate groups at 2,3- and 6-positions than on the cellulose tris(3,5-dimethylphenylcarbamate), which is commercially available as one of the most popular chiral columns, Chiralcel OD. The structures of the obtained cellulose derivatives were also investigated by circular dichroism spectroscopy.


Asunto(s)
Carbamatos/síntesis química , Celulosa/química , Técnicas de Química Analítica/métodos , Cromatografía Líquida de Alta Presión/métodos , Carbamatos/química , Gel de Sílice/química
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