1.Transgenic plant regeneration of tobacco (Nicotiana tabacum) haboring mammalian cyp2e1 gene.
Peihan LI ; Taihe XIANG ; Jun XIE ; Ting FENG ; Wenyi LU
Chinese Journal of Biotechnology 2012;28(10):1195-1204
CYP2E1 enzyme encoded by cyp2e1 gene plays an important role in metabolism of heterogeneous organics in mammalian liver cells. The transgenic plant with cyp2e1 can metabolize various low molecular weight organic pollutants. However, it is unclear the mechanism of expression control of cyp2e1 in transgenic plant. In this study, plasmid pSLD50-6 with cyp2e1 and pKH200 with gus as control were transformed into Agrobacterium tumefaciens GV3101 separately. Then, the cyp2e1 or gus genes were transferred into tobacco (Nicotiana tabacum) and the transgenic plants were regenerated via Agrobacterium tumefaciens method. Real-time quantitative PCR (qRT-PCR) was used to analyze the cyp2e1 gene expression. The expression of cyp2e1 in transgenic tobacco with cyp2e1 decreased obviously treated by ethyl alcohol and reduced slightly by benzene and toluene, while it enhanced by acetone, formaldehyde and oxygen deficit in different levels. In addition, the gene expression of NADPH-P450 oxidoreductase and cytochrome b5 enzyme in the transgenic tobacco with cyp2e1 were increased significantly treated by benzene, which showed that NADPH-P450 oxidoreductase and cytochrome b5 enzyme in transgenic tobacco have relation with CYP2E1 detoxication process. It suggested that the NADPH-P450 oxidoreductase and cytochrome b5 enzyme in transgenic plant formed the requirement in mammalian and participated in the electron transport chain of CYP2E1 enzyme catalytic process.
Agrobacterium tumefaciens
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genetics
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Animals
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Cytochrome P-450 CYP2E1
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biosynthesis
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genetics
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Gene Expression Regulation, Enzymologic
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genetics
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Gene Transfer Techniques
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Genetic Vectors
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genetics
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Plants, Genetically Modified
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genetics
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Soil Pollutants
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isolation & purification
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Tobacco
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enzymology
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genetics
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Transfection
2.Analysis and research of online teaching supervision based on the characteristics of medical disciplines
Jiamin YANG ; Yang ZOU ; Hongyi HU ; Chuanhai PU ; Wei ZHANG ; Yujin LIU ; Peihan LI ; Yu TANG
Chinese Journal of Medical Education Research 2024;23(2):242-245
Given the systematic, rigorous, and practical characteristics of medical disciplines, ensuring the teaching quality of online courses has become a significant focus. In traditional teaching models, teaching supervision is an important method to guarantee instructional quality, and introducing teaching supervision into online teaching activities is of great significance. This article systematically reviews and summarizes the domestic and international experience of conducting online medical courses. We explore the instructional supervision of online medical courses from the following perspectives: the meaning of supervision, the necessity of online supervision, online supervision methods and technical approaches, the feedback and application of supervision information, and the establishment of a standardized online supervision process.
3.Construction of a curcumin-siRNA co-delivery system based on mesoporous silica and its effect on M2-type polarization of macrophages
LI Peihan ; LANG Kai ; SONG Wen
Journal of Prevention and Treatment for Stomatological Diseases 2021;29(5):306-313
Objective :
To fabricate a co-delivery system of curcumin (CUR) and siRNA based on mesoporous silica nanoparticles (MSN) and investigate its potential application in inducing macrophage M2 polarization.
Methods:
MSNs were synthesized using the conventional sol-gel method. The interior mesochannels were occupied by small-molecule CUR, while the exterior surface was adsorbed by cationic polymeric polyethyleneimine (PEI) to link the negatively charged siRNA molecules to formulate the (CUR@MSN)PEI/siRNA co-delivery system. The formulation process was monitored by transmission electron microscopy(TEM). The MTT assay was used to evaluate the cytotoxicity in RAW264.7 cells under various concentrations of nanoparticles. Confocal laser scanning microscopy and TEM were used to observe cell internalization using FAM-labeled siRNA. GAPDH-targeting siRNA was used to prepare nanoparticles and then was transfected into RAW264.7 cells to observe the silencing efficiency of target genes. The knockdown efficiency was examined by real-time quantitative PCR. The related control groups were untreated cells, CUR delivery only and the co-delivery of CUR and siRNA negative control. By loading miRNA-130a-3p antisense oligonucleotide (ASO) to transfect RAW264.7 cells, the effects on the polarization of macrophages were observed. The M2 polarization marker arginase 1 (Arg-1) was measured by western blotting. The related control groups were untreated cells, CUR delivery only and co-delivery of CUR and miRNA negative control.
Results :
The (CUR@MSN)PEI/siRNA co-delivery system was successfully formulated. The nanoparticles exhibited dose-dependent cytotoxicity, and the cell viability was maintained over 90% when the nanoparticle concentration was less than 10 μg/mL. A high cell uptake efficiency was observed, and the target gene knockdown efficiency was greater than 80% (P < 0.05 vs. all the other groups). The CUR delivery-only group and co-delivery of the CUR-and miRNA-negative control group improved Arg-1 expression ~ 3-fold (P < 0.05 vs. untreated cells). Using the co-delivery of CUR and ASO, synergistic effects were obtained, and Arg-1 expression was increased ~ 8-fold (P < 0.05 vs. all the other groups).
Conclusion
The CUR-siRNA co-delivery system can effectively transfect macrophages and synergistically induce M2 polarization.