Objective · To explore the change of metabolomic profiling after erlotinib (anepithelial growth factor receptor tyrosine kinase inhibitor)resistance of lung adenocarcinoma cells (PC9-ER), and find the differential metabolome associated witherlotinib resistance. Methods · Metabolic profiling of PC9-ER cells and homologous parent PC9 cells was acquired by the ultraperformance liquid chromatography tandem quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS). The data were analyzed by multi-dimensional statistical methods, such as partial least squares projection to latent structures-discriminant analysis (PLS-DA), to select and identify differential metabolites associated with erlotinib resistance. Results · A total of 14 differential metabolites were identified in PC9-ER cells. Seven up-regulated metabolites included N-acetylspermidine, phosphatidylethanolamine, AMP, pantothenic acid,proline, glutamate, and histidine, while seven down-regulated metabolites included citrulline, phosphorylcholine, glutathione, cysteinylglycine, glutathione oxidized, NAD, and S-adenosylmethionine, mainly participating in glutathione metabolism, glutamate metabolism, ammonia recycling, and protein biosynthesis. Conclusion · Metabolic profiling of erlotinib-resistant lung adenocarcinoma cells was changed. The information of differential metabolites associated with erlotinib resistance could provide clues for new resistance mechanisms and potential metabolism-related drug targets.

To investigate the modulation on the P-glycoprotein in the jejunum by combined use of Glycyrrhiza inflata and Kansui with ussing chamber and rt-pcr, Rhodamine 123 (R123), a P-gp substrate and fluorescein sodium (CF), a model drug of non-P-gp substrate transported by a passive diffusion were taken as investigational drugs. Because these two drugs can be easily assayed and widely used in various research fields. The permeability of R123 or CF via Wistar rat jejunum membranes was evaluated by in vitro ussing chamber after oral administration of four different decoctions of Glycyrrhiza inflata and Kansui for 1 week. And the concentration of R123 or CF was determined by the fluorospectrophotometry in the receiving solution. Meanwhile the expression of mdr1a in P-glycoprotein was detected by real-time fluorescent quantitative PCR. After oral administration of combined decoction of the single drug, the absorptive directed permeability of R123 increased significantly (P < 0.01). On the other hand, Kansui and combine decoction of the two drugs also decrease the permeability of secretory directed transport (P < 0.05). No action of Glycyrrhiza inflata was found on the secretory transport of R123 [Papp = (2.56 +/- 0.38) x 10(-5), cm x s(-1)] across the jejunum tissues, while Papp of control group was found [Papp = (2.35 +/- 0.27) x 10(-5), cm x s(-1)]. After oral administration of Kansui decoction for 1 week and 2 weeks, the levels of mdr1a expression in Wistar rats were lower than that of the control group, but there were no significant difference in the results. Meanwhile, Glycyrrhiza inflata had no effect on transport of CF across the jejunum tissues, though the other three groups could decrease the permeability of CF, as compared with control group. Kansui may slightly inhibit P-glycoprotein function in the intestinal membrane. For another, some compositions in Kansui inhibit P-glycoprotein function, and some others strengthen the tight junction between cells in the intestinal membrane to decrease permeability of CF. As the inhibitory action to P-glycoprotein was enhanced by combination of Glycyrrhiza inflata and Kansui, based on the results, it may be one of the mechanisms of creating toxicity once co-administration of Glycyrrhiza inflata and Kansui.

Objective:To explore the research hotspots and development trends of the transformation of virtual skill training to practical clinical ability in current medical simulation education, and to conduct visual bibliometric analysis.Methods:Taking 783 pieces of literature related to the transformation of simulation skill training to clinical competence collected from the Web of Science core collection database from 2006 to 2020 as data sources, CiteSpace V was used for visualization processing and analysis, so as to reveal the transformation effect and future research direction.Results:The number of published papers and citations increased exponentially with each year. The United States and Canada were the main research forces, the University of Toronto Medical Center contributed the largest number of research, and Professor McGaghie of Northwestern University was the author with the most published articles. According to the literature co-citation cluster analysis, it is found that the transformation of simulation skill training includes both operation and non-operation skills. High-frequency cited references reflect the knowledge base of this field and research to a certain extent. Research frontiers include the improvement of virtual reality simulators, clinical outcomes of simulated training in pediatrics, nursing, and emergency disciplines, and the design of randomized controlled clinical trials.Conclusion:The research on the clinical effect verification of simulation skill training is developing rapidly in the world. The research on medical skills' transformation represented by minimal invasive surgery such as endoscopy is a hot topic. Non-operational skills including communication skills, teamwork, pediatric emergency skills, and virtual reality technology simulation effects are the research frontiers. The number of researches on the effect of simulation training is small and the effect is unclear. In the future, more randomized controlled studies are still needed to determine the effectiveness of the transformation of simulation training to clinical competence.

Medical microbiology experiment is faced with many problems in online teaching. This study adopts the teaching mode of online live broadcast + operation video + virtual experiment, and make up the operation gap to some extent through operation video and virtual experiment. The mode of assessment is subjective thinking question (closely following the operation process) + experiment design + literature review (focusing on the key technology or new technology of clinical assessment that cannot be carried out due to the limitation of conditions in traditional experiments, such as mass spectrometry, fluorescence quantitative PCR, and G-test), and it is helpful to understand students' mastery of teaching objectives, and the ability of comprehensive application and innovative thinking. The student questionnaire shows that most students hold a positive attitude towards the online experimental teaching mode, and the quality of students' homework shows that most students have a good learning effect.