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81.
Colorectal cancer (CRC) is a major source of morbidity and mortality, characterized by intratumoral heterogeneity and the presence of cancer stem cells (CSCs). Bufalin has potent activity against many tumors, but studies of its effect on CRC stemness are limited. We explored bufalin’s function and mechanism using CRC patient-derived organoids (PDOs) and cell lines. In CRC cells, bufalin prevented nuclear translocation of β-catenin and down-regulated CSC markers (CD44, CD133, LGR5), pluripotency factors, and epithelial–mesenchymal transition (EMT) markers (N-Cadherin, Slug, ZEB1). Functionally, bufalin inhibited CRC spheroid formation, aldehyde dehydrogenase activity, migration, and invasion. Network analysis identified a C-Kit/Slug signaling axis accounting for bufalin’s anti-stemness activity. Bufalin treatment significantly downregulated C-Kit, as predicted. Furthermore, overexpression of C-Kit induced Slug expression, spheroid formation, and bufalin resistance. Similarly, overexpression of Slug resulted in increased expression of C-Kit and identical functional effects, demonstrating a pro-stemness feedback loop. For further study, we established PDOs from diagnostic colonoscopy. Bufalin differentially inhibited PDO growth and proliferation, induced apoptosis, restored E-cadherin, and downregulated CSC markers CD133 and C-Myc, dependent on C-Kit/Slug. These findings suggest that the C-Kit/Slug axis plays a pivotal role in regulating CRC stemness, and reveal that targeting this axis can inhibit CRC growth and progression.  相似文献   
82.
83.
To explore the protective effect of dietary β-glucan (BGL) supplementation on intestinal epithelium exposure to enterotoxigenic Escherichia coli (ETEC), thirty-two weaned pigs were assigned to four groups. Pigs were fed with a basal diet or basal diet containing 500 mg/kg BGL, and were orally infused with ETEC or culture medium. Results showed BGL supplementation had no influence on growth performance in weaned pigs. However, BGL supplementation increased the absorption of D-xylose, and significantly decreased the serum concentrations of D-lactate and diamine oxidase (DAO) in the ETEC-challenged pigs (p < 0.05). Interestingly, BGL significantly increased the abundance of the zonula occludens-1-(ZO-1) in the jejunal epithelium upon ETEC challenge (p < 0.05). BGL supplementation also increased the number of S-phase cells and the number of sIgA-positive cells, but significantly decreased the number of total apoptotic cells in the jejunal epithelium upon ETEC challenge (p < 0.05). Moreover, BGL significantly increased the duodenal catalase (CAT) activity and the ileal total superoxide dismutase (T-SOD) activity in the ETEC-challenged pigs (p < 0.05). Importantly, BGL significantly decreased the expression levels of critical inflammation related proteins such as the tumor necrosis factor-α (TNF-α), interlukin-6 (IL-6), myeloid differentiation factor 88 (MyD88), and nuclear factor-κB (NF-κB) in the jejunal and ileal mucosa upon ETEC challenge (p < 0.05). BGL also elevated the propanoic acid content and the abundance of Lactobacillus and Bacillus in the colon upon ETEC challenge (p < 0.05). These results suggested BGL could alleviate the ETEC-induced intestinal epithelium injury, which may be associated with suppressed inflammation and improved intestinal immunity and antioxidant capacity, as well as the improved intestinal macrobiotic.  相似文献   
84.
The potential for leakage of liquid electrolytes from magnesium (Mg) batteries represents a large hurdle to future application. Despite this, there are no efficient sensing technologies to detect the leakage of liquid electrolytes. Here, we developed a sensor using laccaic acid (L-AIEgen), a naturally occurring aggregation-induced emission luminogen (AIEgens) isolated from the beetle Laccifer lacca. L-AIEgen showed good selectivity and sensitivity for Mg2+, a universal component of electrolytes in Mg batteries. Using L-AIEgen, we then produced a smart film (L-AIE-F) that was able to sense leakage of electrolytes from Mg batteries. L-AIE-F showed a strong “turn-on” AIE-active fluorescence at the leakage point of electrolyte from model Mg batteries. To the best of our knowledge, this is the first time that AIE technology has been used to sense the leakage of electrolytes.  相似文献   
85.
Powdery mildew caused by Blumeria graminis f. sp. tritici is a devastating disease that reduces wheat yield and quality worldwide. The exploration and utilization of new resistance genes from wild wheat relatives is the most effective strategy against this disease. Psathyrostachys huashanica Keng f. ex P. C. Kuo (2n = 2x = 14, NsNs) is an important tertiary gene donor with multiple valuable traits for wheat genetic improvement, especially disease resistance. In this study, we developed and identified a new wheat—P. huashanica disomic addition line, 18-1-5—derived from a cross between P. huashanica and common wheat lines Chinese Spring and CSph2b. Sequential genomic and multicolor fluorescence in situ hybridization analyses revealed that 18-1-5 harbored 21 pairs of wheat chromosomes plus a pair of alien Ns chromosomes. Non-denaturing fluorescence in situ hybridization and molecular marker analyses further demonstrated that the alien chromosomes were derived from chromosome 7Ns of P. huashanica. The assessment of powdery mildew response revealed that line 18-1-5 was highly resistant at the adult stage to powdery mildew pathogens prevalent in China. The evaluation of agronomic traits indicated that 18-1-5 had a significantly reduced plant height and an increased kernel length compared with its wheat parents. Using genotyping-by-sequencing technology, we developed 118 PCR-based markers specifically for chromosome 7Ns of P. huashanica and found that 26 of these markers could be used to distinguish the genomes of P. huashanica and other wheat-related species. Line 18-1-5 can therefore serve as a promising bridging parent for wheat disease resistance breeding. These markers should be conducive for the rapid, precise detection of P. huashanica chromosomes and chromosomal segments carrying Pm resistance gene(s) during marker-assisted breeding and for the investigation of genetic differences and phylogenetic relationships among diverse Ns genomes and other closely related ones.  相似文献   
86.
重解大学校园外部空间环境标识系统   总被引:1,自引:1,他引:0  
该文通过分析标识信息栽体的类型,提出广义标识的概念,并揭示了其在形成校园意向中的重要作用.再此基础上,将校园标识系统分为四大类,进一步探讨了其设计原则.  相似文献   
87.
Lesion mimic mutants are an ideal model system for elucidating the molecular mechanisms of programmed cell death and defense responses in rice. In this study, we identified a lesion mimic mutant termed miner infection like 1-1 (mil1-1). The mil1-1 exhibited lesions on the leaves during development, and the chloroplasts of mil1-1 leaves were disrupted. Reactive oxygen species were found to accumulate in mil1-1 leaves. Cell death and DNA fragmentation were observed in mil1-1 leaves, indicating that the cells in the spots of mil1-1 leaves experienced programmed cell death. Most agronomic traits decreased in mil1-1, suggesting that the growth retardation in mil1-1 caused reduced per-plant grain yield. However, the mutation of MIL1 activated the expression of pathogen response genes and enhanced resistance to bacterial blight. The MIL1 gene was cloned using the positional cloning approach. A missense mutation 751 bp downstream of ATG was found in mil1-1. The defects of mil1-1 were able to be rescued by delivering a wild-type MIL1 gene into mil1-1. MIL1 encoded hydroperoxide lyase 3 (OsHPL3), and the expression of OsHPL3 was induced via hormone and abiotic stresses. Our findings provide insights into the roles of MIL1 in regulating programmed cell death, development, yield, and defense responses in rice.  相似文献   
88.
灌浆作为一种新型的加固技术,用于治理水泥混凝土路面病害具有成本低、见效快、操作简便、对车辆行驶影响小、受自然因素影响小等优点,在公路施工和养护工程中,能够获得可观的经济效益和社会效益。  相似文献   
89.

为有效防止煤炭自燃,以5种不同类型的表面活性剂为基础,2种高分子聚合物为改性添加剂,研制出发泡倍数高、稳定性强、润湿性好的凝胶泡沫,并进行发泡性能和高温阻燃特性测试。研究结果表明:在发泡性能方面,当表面活性剂A与B的质量比为1∶2、总质量浓度为6 g/L,聚合物X的质量浓度为3 g/L时,制备的凝胶泡沫性能最佳;在高温阻燃方面,与原始煤样比较,经凝胶泡沫处理后的煤样点燃时间由27 s延长至334 s,热释放速率峰值从68.08 kW/m2降低至38.46 kW/m2,1 200 s内的总热释放量由41.98 MJ/m2降低至37.12 MJ/m2,阻燃效果显著。

  相似文献   
90.
以新疆南部巴州地区赤霞珠葡萄叶为原料,采用微波辅助法提取葡萄叶中的白藜芦醇,并NKA-Ⅱ树脂进行纯化。实验表明:微波辅助法提取葡萄叶白藜芦醇的最佳工艺条件为:乙醇浓度40%,微波功率640 W,时间76 s,料液比1∶92,在此条件下提取白藜芦醇为13.52 mg/g;经过静态实验筛选,采用NKA-Ⅱ树脂对白藜芦醇粗品进行纯化,其纯化的最佳工艺参数为:6 BV、浓度3 mg/m L、p H4的白藜芦醇样液以2 BV/h通过树脂,用4倍柱体积90%的乙醇以3BV/h的流速洗脱效果最佳,纯度由35.7352 mg/g提高到了181.5888 mg/g。结论:虽然微波辅助法的提取率不是最高的,但时间短,有利于工业生产,纯化虽然有一定效果,但仍需进一步研究。   相似文献   
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