Application of project-driven teaching methods in establishing new model of medical interdisciplinary inno-vative informationists training / 中华医学图书情报杂志

After the characteristics of project-driven teaching methods and traditional teaching methods were com-paratively analyzed,a new gradient and hierarchical "dual-driven" model of medical interdisciplinary innovative informationists training was established by embedding the general model of project-driven teaching methods into the traditional training model of medical interdisciplinary innovative informationists training in order to improve the teaching level and find a new way for medical informationists training.

Over-expression of DLL4/Notch1 ligand inhibits proliferation of K562 cells / 中国实验血液学杂志

This study was aimed to explore the effect of DLL4/Notch1 ligand on cell growth in leukemia cell line K562 and its relevant mechanism. The pBudCE4.1-DLL4 plasmid was transfected into K562 cells by lipofectamine 2 000, RT-PCR and Western blot were applied to monitor the mRNA and the protein expression of exogenous DLL4 gene, as well as the expression of Notch1-ICD and target gene Hes1. Expression levels of Rb, YY1 and C-MYC protein in K562 cells were also detected by Western blot. Cell counting Kit-8 was used to detect the proliferation of K562 cells, and flow cytometry with Annexin V staining was used to detect the cell apoptosis. The results showed that the mRNA and protein expression levels of DLL4, Notch1-ICD and Hes1 in cells of experimental group were significantly higher than those of control groups (P < 0.05), indicating the successful activation of the Notch1 signaling pathway. The protein expression levels of Rb, YY1 and C-MYC in cells of experimental group significantly increased when compared with that of control group cells (P < 0.05). After transfection, the proliferation of K562 cells was obviously inhibited, and apoptosis rate in DLL4-transfected cells was significantly enhanced. DLL4 transfection significantly increased the number of cells in G1 phase and decreased that in S phase. It is concluded that the over-expression of DLL4 ligand gene in K562 cells results in successful activation of the Notch1 signaling pathway, increases expression of Rb, YY1 and C-MYC genes, which induces apoptosis and reduces proliferation.

Effects of DLL4 gene on YY1 and c-Myc protein expression and cell proliferation in leukemia cell line K562 / 中国实验血液学杂志

This study was aimed to explore the effects of Notch ligand DLL4 on the protein expression of the transcription factor YY1 and proto-oncogene c-Myc, as well as K562 cell proliferation. The experiment was divided into 3 groups: normal control, negative control (pBudCE4.1-transfected) and experimental (pBudCE4.1-DLL4-transfected) groups. At 48 hours after transfection, the expression level of DLL4, YY1 and c-Myc proteins in K562 cells of each group were detected by Western blot and indirect immunocytochemical method; the CCK-8 method was used to detect proliferation of K562 cells; at 48 hours after transfection, cell cycle distribution and apoptosis of K562 cells were detected by flow cytometry. The results showed that the protein expression of DLL4, YY1 and c-Myc in K562 cells of every group were found. The protein expression levels of DLL4, YY1 and c-Myc in the experimental group cells were significantly higher than that in control groups (p < 0.05). The cell number in G(0)/G(1) phase increased in the experimental group and was higher than that in the control groups (p < 0.001), and the number of apoptotic cells were also increased (p < 0.001). It is concluded that DLL4 gene was successfully transfected into K562 cells, which increased the protein expression levels of transcription factor YY1 and proto-oncogene c-Myc, leading to the cell proliferation slower in experiment group, inducing the cell cycle arrested in G(0)/G(1) phase and increasing apoptosis.