查找使用阿拉丁产品的科研文献

Hypericin-mediated photodynamic therapy enhances gemcitabine induced Capan-2 cell apoptosis via inhibiting NADPH level

Sun Liyun,Shang Huoli,Wu Yuzhen,Xin Xiujuan

ObjectivesThe combination of gemcitabine (Gem) and hypericin (HY) enhances the apoptosis of Capan-2 cells, providing a promising option for the treatment of pancreatic cancer. Our study further explored the cytotoxic mechanism of HY combined with chemotherapy drugs on pancreatic cancer.MethodsThe proliferation rate of the cells assayed with the MTT method. The ROS (reactive oxygen species) levels of each treatment were evaluated by DCFH-DA oxidisation methods. The activity of glutathione reductase and the levels of reduced glutathione (GSH) and oxidised glutathione (GSSG) were assessed using assay kits. The expression levels of apoptosis-related proteins were analysed by western blotting.Key findingsThe activity of glucose-6-phosphate dehydrogenase (G6PDH), a key enzyme of the pentose phosphate pathway, significantly decreased in Gem + HY groups, however, the ROS level enhanced accompanying with GSH depleting, mitochondrial membrane depolarisation and cytochrome C release. Gem + HY inhibits the expression of Bcl-2 but stimulates Bax level, triggering caspase activation and PARP cleavage and thus promoted apoptosis of Capan-2 cells.ConclusionsWe demonstrated that Gem combined HY-PDT could inhibit the proliferation of Capan-2 cells and induce cell apoptosis. HY-PDT combined with Gem had a great potential on pancreatic cancer treatment clinically.

A DNAzyme-assisted triple-amplified electrochemical aptasensor for ultra-sensitive detection of T-2 toxin

Long Wang,Huali Jin,Min Wei,Wenjie Ren,Yurong Zhang,Liying Jiang,Tao Wei,Baoshan He

Herein, an electrochemical aptasensor was constructed for ultra-sensitive determination of T-2 toxin based on Silver ion (Ag + ) -dependent DNAzyme-assisted signal amplification and Gold nanoparticles/Graphene oxide @ manganese dioxide (AuNPs/MnO 2 @GO) nanocomposites. In the presence of Ag + , the secondary structure of the T-2 aptamer is altered via the Ag + mediated coordination of C–Ag + –C base pairs. When T-2 toxin is added, the secondary structure of DNA is changed again, and the trapped Ag + are released. Then, the DNAzyme could repeatedly bind and cleave methylene blue (MB)-modified substrate DNA (S-DNA) in the assistance of Ag + , which leads to a decrease in the electrochemical signal. With the optimal conditions, there is a good linear relationship between the current value and the logarithm of T-2 toxin concentration in the range from 2 fg mL −1 to 20 ng mL −1 , and a detection limit of 0.107 fg mL −1 is obtained. Moreover, the proposed method was successfully applied to measure T-2 toxin in beer, thus showing great potential of this system for food safety and quality control.

Activation of peroxydisulfate by a novel Cu0-Cu2O@CNTs composite for 2, 4-dichlorophenol degradation

Yong Liu,Yang Zhao,Jianlong Wang

In this study, a novel Cu 0 -Cu 2 O@CNTs composite was synthesized, characterized and applied to activate peroxydisulfate (PDS) for the degradation of 2, 4-dichlorophenol (2,4-DCP) in contaminated lake water. The results indicated that Cu 0 -Cu 2 O@CNTs can effectively activate PDS to produce O 2 • − radical, which has high selectivity to degrade organic pollutants in actual contaminated water. The efficiency of 2,4-DCP degradation and mineralization was 99.27% and 66.90%, respectively under the optimal condition. In the presence of Cl − , HCO 3 − and natural organic matters (NOMs) or in real wastewater containing 2,4-DCP, Cu 0 -Cu 2 O@CNTs/PDS system had a good selectivity for 2,4-DCP degradation. O 2 • − was the dominant reactive species in Cu 0 -Cu 2 O@CNTs/PDS system for 2,4-DCP degradation. The possible degradation pathway of 2,4-DCP was proposed. It was concluded that Cu 0 -Cu 2 O@CNTs composite could overcome the shortcomings of PDS activation by Cu 0 and Cu 2 O alone, such as low activating capability of Cu 0 and instability of Cu 2 O, which was high efficient for activating PDS. Cu 0 -Cu 2 O@CNTs composite can be used as an efficient catalyst to activate PDS for the degradation of toxic organic pollutants in water and wastewater.

Biocompatible Ionic Liquid Promote One-Pot Synthesis of 2-Amino-4H-Chromenes Under Ambient Conditions

Zhu Anlian,Li Qixing,Feng Wanlu,Fan Dongshuang,Li Lingjun

Abstract The synthesis of 2-amino-4H-chromenes through one-pot multicomponent reactions has received great attention due to the high atom efficiency and the broad bioactivities of the products. Here, the catalytic performances of a series of functional ionic liquids towards this type of reaction were investigated and the results showed that the ionic liquid, choline acetate ([Choline][Ac]), could efficiently promote this reactions under room temperature without the necessary of organic solvents. The reaction is easy to be conducted and the following work-up procedures are very simple. The pure products can be obtained through extraction and washing procedures, no column separation procedures are needed. Intriguingly, this reaction system can be easily scaled up to multi-gram, suggesting its perspective in industrial applications. In addition, the ionic liquid [Choline][Ac] can be easily prepared from cheap and biocompatible materials, and it can be feasibly recycled and reutilized for at least five cycles. Graphic Abstract Various aldehydes, malononitrile and activated phenols could be converted to the corresponding 2-amino-4H-chromenes with good to excellent isolated yields under the catalysis of choline acetate at room temperature.

Atomically dispersed Lewis acid sites boost 2-electron oxygen reduction activity of carbon-based catalysts

Yang Qihao,Xu Wenwen,Gong Shun,Zheng Guokui,Tian Ziqi,Wen Yujie,Peng Luming,Zhang Linjuan,Lu Zhiyi,Chen Liang

Elucidating the structure-property relationship is crucial for the design of advanced electrocatalysts towards the production of hydrogen peroxide (H 2 O 2 ). In this work, we theoretically and experimentally discovered that atomically dispersed Lewis acid sites (octahedral M–O species, M = aluminum (Al), gallium (Ga)) regulate the electronic structure of adjacent carbon catalyst sites. Density functional theory calculation predicts that the octahedral M–O with strong Lewis acidity regulates the electronic distribution of the adjacent carbon site and thus optimizes the adsorption and desorption strength of reaction intermediate (*OOH). Experimentally, the optimal catalyst (oxygen-rich carbon with atomically dispersed Al, denoted as O-C(Al)) with the strongest Lewis acidity exhibited excellent onset potential (0.822 and 0.526 V versus reversible hydrogen electrode at 0.1 mA cm −2 H 2 O 2 current in alkaline and neutral media, respectively) and high H 2 O 2 selectivity over a wide voltage range. This study provides a highly efficient and low-cost electrocatalyst for electrochemical H 2 O 2 production.

Facile Synthesis of Au/Ni(OH)2 Nanocomposites and its Application in Nonenzymatic Glucose Sensing

Zhang Yingzhen,Song Yingying,Li Yancai

A simple and environment-friendly autocatalytic reduction process was developed for synthesis of Au/Ni(OH) 2 nanocomposites. The nanocomposites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). It is found the nanocomposites are composed of ultrathin Ni(OH) 2 nanosheets and gold nanoparticles (AuNPs), and the AuNPs disperse evenly on the Ni(OH) 2 nanosheets. The electrochemical and electrocatalytic properties of the Au/Ni(OH) 2 modified glassy carbon electrode (Au/Ni(OH) 2 /GCE) were investigated by electrochemical experiments. Furthermore, through optimizing Au loading of the nanocomposites, the 5%-Au/Ni(OH) 2 /GCE displays the best electrocatalytic activity towards glucose oxidization in alkaline medium. Under optimal conditions, the 5%-Au/Ni(OH) 2 /GCE displays a wide linear range of 0.01 to 3.15 mM (R 2  = 0.998) to glucose. Besides, the sensor has a low detection limit of 0.10 μM (S/N = 3) and a high sensitivity of 342.1 μA·mM −1 ·cm −2 . It also displays satisfying stability, good reproducibility and selectivity.

Predicting Di-2-Ethylhexyl Phthalate Toxicity: Hybrid Integrated Harris Hawks Optimization With Support Vector Machines

Beibei Shi,Ali Asghar Heidari,Cheng Chen,Mingjing Wang,Changcheng Huang,Huiling Chen,Jiayin Zhu

Myeloid differentiation protein 2 mediates angiotensin II-induced inflammation and mesenchymal transition in vascular endothelium

Jinfu Qian,Wu Luo,Chengyi Dai,Jun Wang,Xinfu Guan,Chunpeng Zou,Nipon Chattipakorn,Gaojun Wu,Weijian Huang,Guang Liang

Angiotensin II (Ang II)-induced vascular inflammation and injury entails endothelial to mesenchymal transition (EndMT). Recent studies have shown that Ang II engages toll-like receptor 4 (TLR4) in the vasculature to mediate adverse effects. Here, we aimed to investigate whether myeloid differentiation protein 2 (MD2), an extracellular molecule indispensable for TLR4 activation, mediates Ang II-induced vascular injury and EndMT. We utilized MD2 knockout mice and wildtype mice treated with a specific MD2 inhibitor to decipher its role in aortas of Ang II-challenged mice. To confirm our results and to provide mechanistic insights, we exposed cultured endothelial cells to Ang II, with or without MD2 silencing. We show that Ang II causes deleterious remodeling and EndMT in aortas of mice within two weeks. These Ang II effects were largely absent in MD2 knockout mice and in wildtype mice treated with a MD2 inhibitor. MD2 silencing in cultured endothelial cells confirmed the essential role of MD2 in Ang II-induced inflammatory factor induction, and EndMT-associated phenotypic change. We also found that Ang II-MD2-EndMT axis involves the activation of nuclear factor-κB. Our studies highlight an essential role of MD2 in Ang II-induced vascular inflammation and EndMT contributing to vascular injury. These results also imply that MD2 may be targeted to dampen inflammatory cardiovascular and EndMT-associated diseases.

Performance and mechanism of CO2 absorption in 2-ethylhexan-1-amine + glyme non-aqueous solutions

Kun Fu,Chenxu Liu,Lemeng Wang,Xiayu Huang,Dong Fu

In this work, novel non-aqueous absorbents composed of 2-ethylhexan-1-amine (EHA) and glyme were proposed for CO 2 capture. The absorption performance of CO 2 in EHA + diglyme, EHA + triglyme and EHA + tetraglyme non-aqueous solutions was investigated and the viscosities ( η ) of the CO 2 -saturated absorbents were measured. Besides the experiments, kinetic models were applied to correlate the CO 2 absorption. The activation energy ( E a ) was obtained from Arrhenius equation , and the absorption mechanism was deduced. The results showed that both Lagergren model and Avrami model can accurately correlate and predict the time-dependent absorption amount, thus an optimized composition under which excellent absorption performance and relatively low η and E a can be simultaneously achieved was determined. Compared to water-based absorbents like MEA, the optimized non-aqueous absorbents take the advantages of better absorption performance and lower activation energy. Moreover, the glyme solvents have about 50% lower specific heat capacities and much higher boiling points (≥435 K) than water, which is expected to greatly reduce the sensible heat and the latent heat of the solvent during regeneration. Therefore, the proposed novel absorbents have promising industrial application potential in the CO 2 capture process.

5-Aza-2-deoxycytidine inhibits osteolysis induced by titanium particles by regulating RANKL/OPG ratio

Yafei Wang,Huimin Liu,Jianmin Wu,Yunjian Liao,Daifeng Lu,Feng Dong,Hongxi Li,Zhitao Zhang,Yongyun Lian

Periprosthetic osteolysis (PIO) caused by wear particles is the main cause of implant failure, which is regulated by nuclear factor κ B receptor activator ligand (RANKL)/osteoprotegerin (OPG) system. At present, there is a lack of effective drugs to prevent or treat PIO. Previous studies have confirmed that DNA methylation is closely related to postmenopausal osteoporosis and can affect the expression of OPG and RANKL . However, the relationship between DNA methylation and PIO is not clear. In this study, we investigated the inhibitory effect of 5-Aza-2-deoxycytidine (AzadC) on osteolysis induced by titanium particles in a mouse model. This inhibition mechanism is achieved by changing the ratio of RANKL/OPG in the osteolysis model. In conclusion, there is a relationship between DNA methylation and PIO. AzadC has a certain inhibitory effect on osteolysis induced by titanium particles. Regulating DNA methylation may be a new way to treat PIO. Our findings lay a foundation for epigenetic understanding and intervention of osteolysis.

HYR-2 plays an anti-lung cancer role by regulating PD-L1 and Akkermansia muciniphila

Linxin Teng,Kaiyuan Wang,Weiping Chen,Yun-shan Wang,Lei Bi

Traditional Chinese medicine (TCM) plays a vital part in cancer treatment due to its unique superiority. Huoxue Yiqi Recipe-2 (HYR-2) was supposed to have therapeutic effect on lung cancer, which came from Ze Qi Decoction in one of the four great classics of TCM called "Synopsis of Prescriptions of the Golden Chamber". Network pharmacology demonstrated that the targets of active components from HYR-2 were significantly enriched in the signaling pathways, which were closely associated with non-small cell lung cancer (NSCLC) and programmed death ligand 1 (PD-L1). Then, data about NSCLC was downloaded from Gene Expression Omnibus database (GEO). The Cancer Genome Atlas (TCGA) and DisGeNET was analyzed by bioinformatics, and 214 biomarkers for NSCLC were obtained, containing 14 targets of active components from HYR-2 (which were significantly enriched in the PD-L1 related signaling pathway). In vivo and in vitro experiments showed that HYR and HYR-2 could inhibit the growth of lung cancer and down-regulate the expression of PD-L1, which might be related to the blocking effect of HYR-2 on the PI3K/Akt signaling pathway. Furthermore, HYR-2 promoted the transformation of M2 macrophages into M1 macrophages as well. It is deserved to be mentioned that the level of Akkermansia muciniphila was also significantly elevated by HYR-2, which was believed to enhance the therapeutic effect of PD-L1 antibodies. To sum up, HYR-2 might play an anti-lung cancer effect by down-regulating PD-L1 together with up-regulating Akkermansia muciniphila.

Development of a Promising Biphasic Absorbent for Postcombustion CO2 Capture: Sulfolane + 2-(Methylamino)ethanol + H2O

Juan Lv,Sen Liu,Hao Ling,Hongxia Gao,Wilfred Olson,Qiang Li,Zain Ali Saleh Bairq,Zhiwu Liang

A new sulfolane/secondary amine biphasic absorbent, sulfolane/2-methylaminoethanol (MAE) solution, was developed for postcombustion CO2 capture (PCC). Surprisingly, using a 4M/5M sulfolane/MAE solution saves about 60% energy consumption (EC) for CO2 stripping when compared with traditional aqueous 5M monoethanolamine (MEA) solutions. First, we theoretically proved that MAE in sulfolane-based biphasic solution improves the CO2 absorption rate with high CO2 loading at the phase-changing point, which could be energy-saving for CO2 stripping. Based on a comprehensive comparison of the phase-changing behavior, nuclear magnetic resonance (NMR) spectra, absorption rate, and desorption performance, the 4M/5M sulfolane/MAE was determined to be the optimal molar ratio among six sulfolane/MAE biphasic solutions for CO2 capture. In addition, the absorption and desorption experiments with various temperatures revealed that relatively low temperature (ranging from 110 to 120 °C) was favorable for CO2 removal and energy-saving. Furthermore, the 4M/5M sulfolane/MAE solution achieved a very low energy consumption (EC) compared with that of 5M MEA solution, and the stripped CO2 amount is similar to that of 5M MEA and 5M MAE solutions.