Fluorescent chemosensors 1 and 2, with 1,2,4-oxadiazoles as the binding ligands and anthracene as the fluorophore, were synthesized through sequential 1,3-dipolar cycloaddition reactions of 25,27-dioxyacetonitrilecalix[4]arenes 8 and 11. The fluorescence of 1 was severely quenched by both Fe(3+) and Cu(2+) , whereas that of 2 was selectively quenched only by Fe(3+) . Control compound 4 was also selectively quenched by Fe(3+) , which implied the importance of anthryl-1,2,4-oxadiazole core; furthermore, it was shown to give various oxidation products such as oxanthrone 13, anthraquinone 14, and imidazolyl oxanthrone 15. In addition to product separation and identification, the fluorescent quenching mechanism of these 9-anthryl-1,2,4-oxadiazolyl derivatives by Fe(3+) is also discussed. Furthermore, it should be noted that the oxadiazole-substituted anthracene 4 and calix[4]arene 2 are Fe(3+) -selective fluorescent chemodosimeters without the interference by Cu(2+) .
Herein, we evaluated the anti-cancer effect and molecular mechanisms of a novel betulinic acid (BA) derivative, SYK023, by using two mouse models of lung cancer driven by KrasG12D or EGFRL858R. We found that SYK023 inhibits lung tumor proliferation, without side effects in vivo or cytotoxicity in primary lung cells in vitro. SYK023 triggered endoplasmic reticulum (ER) stress. Blockage of ER stress in SYK023-treated cells inhibited SYK023-induced apoptosis. In addition, we found that the expression of cell cycle-related genes, including cyclin A2, B1, D3, CDC25a, and CDC25b decreased but, while those of p15INK4b, p16INK4a, and p21CIP1 increased following SYK023 treatment. Finally, low doses of SYK023 significantly decreased lung cancer metastasis in vitro and in vivo. Expression of several genes related to cell migration, including synaptopodin, were downregulated by SYK023, thereby impairing F-actin polymerization and metastasis. Therefore, SYK023 may be a potentially therapeutic treatment for metastatic lung cancer.
Water deficit during the growing season is a major factor limiting vegetable production. Therefore, saving water used for vegetable production by applying regulated deficit irrigation (RDI) can be a strategy to reduce water supply. The effects of different RDI levels from irrigation systems on vegetable yields, yield components, water use, and water use efficiency (WUE) of maize, lettuce, and garland chrysanthemum were investigated in a pot experiment. Plants were subjected to four irrigation levels, as follows: full irrigation as a control (RDI-100), 70% of full irrigation (RDI-70), 50% of full irrigation (RDI-50), and 30% of full irrigation (RDI-30). The WUE values of maize and lettuce were significantly higher with RDI-30 than other treatments, yet a significant reduction of WUE in garland chrysanthemum was detected compared to other treatments. There were significant correlations of WUEi with WUEyield and WUEbiomass in maize plants, indicating that WUEi can be a useful nondestructive estimator of yields and biomass contents in maize. Moreover, a significant correlation between WUEi and WUEyield in lettuce plants was observed. This index was correlated with economic production, and can be used to assess fresh weights and as an index of the irrigated water content. These results for evaluating water deficits in plants used nondestructive measurements that are applicable to large-scale water management of vegetable plants, thereby enabling scarce water resources to be conserved.
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