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21.
Kewang Luo Ning Li Wei Ye Hanchao Gao Xinle Luo Baohui Cheng 《Molecules (Basel, Switzerland)》2022,27(14)
Stimulator of interferon gene (STING), an intracellular receptor in the endoplasmic reticulum, could induce the production of cytokines such as type I interferon (IFN) by activating the cGAS-STING signal pathway. In recent years, activation of STING has shown great potential to enhance anti-tumor immunity and reshape the tumor microenvironment, which is expected to be used in tumor immunotherapy. A number of STING agonists have demonstrated promising biological activity and showed excellent synergistic anti-tumor effects in combination with other cancer therapies in preclinical studies and some clinical trials. The combination of STING agonists and ICI also showed a potent effect in improving anti-tumor immunity. In this review, we introduce the cGAS-STING signaling pathway and its effect in tumor immunity and discuss the recent strategies of activation of the STING signaling pathway and its research progress in tumor immunotherapy. 相似文献
22.
Xinyi Liu Ying Tang Weiyu Ning Yihong Bao Ting Luo Jinling Wang 《Molecules (Basel, Switzerland)》2022,27(9)
This study aimed to elucidate the responses of a novel characterized Issatchenkia terricola WJL-G4 against citric acid stress by performing physiological analysis, morphology observation, and structural and membrane fatty acid composition analysis. The results showed that under citric acid stress, the cell vitality of I. terricola WJL-G4 was reduced. The cell morphology changed with the unclear, uncompleted and thinner cell wall, and degraded the cell structure. When the citric acid concentration was 20 g/L, I. terricola WJL-G4 could tolerate citric acid and maintain the cell structure by increasing the intracellular pH, superoxide dismutase activity, and contents of unsaturated fatty acids. As the citric acid concentration was ≥80 g/L, the stress has exceeded the cellular anti-stress ability, causing substantial cell damage. The cell membrane permeability, the content of membrane lipids, malondialdehyde and superoxide anion increased, but the intracellular pH and superoxide dismutase activities decreased, accompanying the increase of citric acid concentrations. The findings of this work provided a theoretical basis for the responsive mechanism of I. terricola WJL-G4 under high concentrations of citric acid, and can serve as a reference for biological acid reduction in fruit processing. 相似文献
23.
Shengnan Xie Li Li Baihe Zhan Xue Shen Xuming Deng Wenxi Tan Tianqi Fang 《Molecules (Basel, Switzerland)》2022,27(9)
The emergence of the plasmid-mediated colistin resistance gene mcr-1 has resulted in the loss of available treatments for certain severe infections. Here we identified a potential inhibitor of MCR-1 for the treatment of infections caused by MCR-1-positive drug-resistant bacteria, especially MCR-1-positive carbapenem-resistant Enterobacteriaceae (CRE). A checkerboard minimum inhibitory concentration (MIC) test, a killing curve test, a growth curve test, bacterial live/dead assays, scanning electron microscope (SEM) analysis, cytotoxicity tests, molecular dynamics simulation analysis, and animal studies were used to confirm the in vivo/in vitro synergistic effects of pogostone and colistin. The results showed that pogostone could restore the bactericidal activity of colistin against all tested MCR-1-positive bacterial strains or MCR-1 mutant–positive bacterial strains (FIC < 0.5). Pogostone does not inhibit the expression of MCR-1. Rather, it inhibits the binding of MCR-1 to substrates by binding to amino acids in the active region of MCR-1, thus inhibiting the biological activity of MCR-1 and its mutants (such as MCR-3). An in vivo mouse systemic infection model, pogostone in combination with colistin resulted in 80.0% (the survival rates after monotherapy with colistin or pogostone alone were 33.3% and 40.0%) survival at 72 h after infection of MCR-1-positve Escherichia coli (E. coli) ZJ487 (blaNDM-1-carrying), and pogostone in combination with colistin led to one or more order of magnitude decreases in the bacterial burdens in the liver, spleen and kidney compared with pogostone or colistin alone. Our results confirm that pogostone is a potential inhibitor of MCR-1 for use in combination with polymyxin for the treatment of severe infections caused by MCR-1-positive Enterobacteriaceae. 相似文献
24.
聚合物作为一种有机发光材料,由于在平板显示和光电子器件中的良好应用前景而受到广泛研究[1~2].近年来,一个重要进展是在聚合物中观测到了受激发射(简称Poly-mer激光)现象[3~6].Polymer激光最早是在溶液中实现的[3~4].作为一种新型... 相似文献
25.
Main observation and conclusion
We reported for the first time that ethyl bromodifluoroacetate directly reacts with azaindole without transition metal catalysis... 相似文献
26.
27.
A unique ultrafine full-vulcanized powdered ethyl acrylate rubber (EA-UFPR) was used as the toughening modifier for poly (lactic acid) (PLA). Largely improved tensile toughness was successfully achieved with the incorporation of only 1 wt% EA-UFPR, while the tensile strength and modulus of the blends were almost the same as pure PLA. The highly efficient toughening of PLA by UFPR is mainly ascribed to the strong interfacial interaction between PLA and UFPR and good dispersion of UFPR particles in PLA matrix. Our work provides an effective toughening method to largely improve the mechanical properties of PLA without sacrificing its stiffness, which is very important for the wide application of PLA materials. 相似文献
28.
Bao-Lei Wang Qing-Nan Li Yi-Zhou Zhan Li-Xia Xiong Shu-Jing Yu Zheng-Ming Li 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):483-491
Abstract A novel series of pyrazole derivatives containing substituted phenylsulfinyl/sulfonyl group have been synthesized via the oxidation of intermediate pyrazole sulfoether with H2O2 in acetic acid. The novel compounds were characterized by melting point, 1H NMR, FT-IR, MS, and elemental analysis or HRMS. The biological activity results showed that most of the title compounds exhibit significant fungicidal activities against Alternaria solani Sorauer, Phytophthora capsici, and Corynespora cassiicola. [Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental files: Additional text and figures.] 相似文献
29.
30.
An experimental investigation on shortening of travelling-wave ASE employing a transversal pumping is presented. A N2 laser with =337.1 nm, pulsewidth: 700 ps is used as a pump source. An ASE pulse with duration of 45, 55 and 45 ps from dye solution of Rh 6G, Rh B and C311, respectively, is obtained. Pulse shapes of output signals generated from these solutions in three different pumping schemes are compared. 相似文献