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991.
Xue Li Xinfeng Tan Qingshuang Chen Xiaoling Zhu Jing Zhang Jie Zhang Baolei Jia 《Molecules (Basel, Switzerland)》2021,26(8)
Prodigiosin is a red pigment produced by Serratia marcescens with anticancer, antimalarial, and antibacterial effects. In this study, we extracted and identified a red pigment from a culture of S. marcescens strain ZPG19 and investigated its effect on the growth performance and intestinal microbiota of Kunming mice. High-performance liquid chromatography/mass spectrometry revealed that the pigment had a mass-to-charge ratio (m/z) of 324.2160, and thus it was identified as prodigiosin. To investigate the effect of prodigiosin on the intestinal microbiota, mice (n = 5) were administered 150 μg/kg/d prodigiosin (crude extract, 95% purity) via the drinking water for 18 days. Administration of prodigiosin did not cause toxicity in mice. High-throughput sequencing analysis revealed that prodigiosin altered the cecum microbiota abundance and diversity; the relative abundance of Desulfovibrio significantly decreased, whereas Lactobacillus reuteri significantly increased. This finding indicates that oral administration of prodigiosin has a beneficial effect on the intestinal microbiota of mice. As prodigiosin is non-toxic to mouse internal organs and improves the mouse intestinal microbiota, we suggest that it is a promising candidate drug to treat intestinal inflammation. 相似文献
992.
Miao Tian Zhonglong Lin Xu Wang Jing Yang Wentao Zhao Hongmei Lu Zhimin Zhang Yi Chen 《Molecules (Basel, Switzerland)》2021,26(9)
Untargeted metabolomics based on liquid chromatography coupled with mass spectrometry (LC–MS) can detect thousands of features in samples and produce highly complex datasets. The accurate extraction of meaningful features and the building of discriminant models are two crucial steps in the data analysis pipeline of untargeted metabolomics. In this study, pure ion chromatograms were extracted from a liquor dataset and left-sided colon cancer (LCC) dataset by K-means-clustering-based Pure Ion Chromatogram extraction method version 2.0 (KPIC2). Then, the nonlinear low-dimensional embedding by uniform manifold approximation and projection (UMAP) showed the separation of samples from different groups in reduced dimensions. The discriminant models were established by extreme gradient boosting (XGBoost) based on the features extracted by KPIC2. Results showed that features extracted by KPIC2 achieved 100% classification accuracy on the test sets of the liquor dataset and the LCC dataset, which demonstrated the rationality of the XGBoost model based on KPIC2 compared with the results of XCMS (92% and 96% for liquor and LCC datasets respectively). Finally, XGBoost can achieve better performance than the linear method and traditional nonlinear modeling methods on these datasets. UMAP and XGBoost are integrated into KPIC2 package to extend its performance in complex situations, which are not only able to effectively process nonlinear dataset but also can greatly improve the accuracy of data analysis in non-target metabolomics. 相似文献
993.
Fanchen Jing Guiliang Li Yingsa Wang Shangbin Zhu Rundong Liu Jing He Jiandu Lei 《先进技术聚合物》2021,32(1):343-354
Carboxymethyl chitosan (CMCS), as a water‐soluble, biocompatible, and biodegradable polymer, is an excellent carrier for a sustained drug delivery system. In this study, a amphiphilic carboxymethyl chitosan‐ursolic acid nano‐drug carrier modified by folic acid (FPCU) were prepared, and then the nano‐drug carrier wrapped another anticancer drug 10‐hydroxycamptothecin were self‐assembled into nanoparticles (FPCU/HCPT NPs). The FPCU/HCPT NPs had a suitable size, high drug loading efficiency of ursolic acid (6.4%) and 10‐hydroxycamptothecin (14.1%). The drug release study in vitro indicated that the nanoparticles have obviously sustained effect and pH sensitive behaviors, the drug release amount was higher at pH 5.5 than at pH 7.4. in vitro and in vivo study showed that the nanoparticles displayed a high antitumor efficiency to tumor cells compared with free drug. The nano delivery system as a carrier for ursolic acid (UA) and 10‐hydroxycamptothecin (HCPT) has good application prospects in cancer treatment. 相似文献
994.
Jing Zhang Yaling Tan Guorong Li Lexian Chen Minyi Nie Zhaohua Wang Hong Ji 《Molecules (Basel, Switzerland)》2021,26(4)
Coumarins possesses immeasurable antitumor potential with minimum side effects depending on the substitutions on the basic nucleus, which exhibits great prospects for antitumor drug development. In an attempt to develop novel antitumor candidates, a series of coumarin sulfonamides and amides derivatives were designed and synthetized. The majority of these derivatives showed good cytotoxic activity against MDA-MB-231 and KB cell lines, among which compound 9c was the most potent against MDA-MB-231 cells, with IC50 value of 9.33 μM, comparable to 5-fluorouracil. Further investigation revealed that compound 9c had versatile properties against tumors, including inhibition of cell migration and invasion as well as inducing apoptosis. Reactive oxygen species (ROS) assay and western blotting analysis suggested that compound 9c promoted cancer cell apoptosis by increasing ROS levels and upregulating the expression of caspase-3 in MDA-MB-231 cells. These results indicated that compound 9c could be promising lead compound for further antitumor drug research. 相似文献
995.
金属有机框架(MOFs)具有大量的孔隙结构和活性位点,在气体吸附、催化、医疗等领域均发挥了巨大的作用。MOFs是晶体粉末,具有脆性较大、在水中易分解和不易回收等缺点,从而限制了其应用。通过MOFs与柔性高分子的复合,特别是与水凝胶的复合,极大地改善了复合材料的柔顺性、可回收和可加工性等特性,进一步拓宽了MOFs的应用领域。本文详细阐述了基于水凝胶MOFs原位生成法、MOFs /水凝胶同时生成法和水凝胶包裹MOFs法等三种不同方法制备MOFs/水凝胶复合材料的研究进展,并对上述三种制备方法的特点及其产物特征进行了总结,进一步归纳了复合材料在生物医药、催化、废水处理和气体吸附等领域的应用。最后,对MOFs/水凝胶复合材料制备方法的改进和复合材料应用前景进行了深入讨论和展望。 相似文献
996.
Both electrospinning apparatus and their commercial pro-ducts are extending their applications in a wide variety of fields. However, very limited reports can be found about how to implement an energy-saving process and in turn to reduce the production cost. In this paper, a brand-new type of coaxial spinneret with a solid core and its electrospinning methods are developed. A novel sort of medicated Eudragit/lipid hybrid nanofibers are gene-rated for providing a colon-targeted sustained release of aspirin. A series of characterizations demonstrates that the as-prepared hybrid nanofibers have a fine linear morphology with the aspirin/lipid separated from the matrix Eudragit to form many tiny islands. In vitro dissolution tests exhibit that the hybrid nanofibers are able to effectively prevent the release of aspirin under an acid condition (8.7%±3.4% for the first two hours), whereas prolong the drug release time period under a neutral condition(99.7±4.2% at the se-venth hour). The energy-saving mechanism is discussed in detail. The prepared aspirin-loaded hybrid nanofibers can be further transferred into an oral dosage form for potential application in counte-ring COVID-19 in the future. 相似文献
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本着培养涂料行业精英人才的宗旨,针对涂料行业对人才需求的特点,结合多年教学经验,从教材的选择、教学内容设置、教学方法改进以及考核方法改革等4个方面探索了“功能涂料”课程的教学方法改革与课程实践。通过自编教材,精心设置授课内容,将科研成果、前沿知识、生活场景、新闻事件与书本知识相结合,提高课堂的趣味性;通过讨论法和交换式互动上课来加强课堂的互动性;通过过程性评价提高课程的学业挑战度。通过教学改革,本课程的选课率和出勤率得到了大幅提高,学生对涂料的兴趣明显增加,毕业后选择进入涂料领域工作的学生也越来越多。 相似文献