Objective To study the effects of eliminating free radical and increasing antioxidative capacity of glutathione peroxidase 1(GPX1) on PC12 cells. MethodsGPX1 recombinant plasmid and Plncxplasmid were transfected into PC12 cells and PC12 cells highly-expressing GPX1 stably were sieved by G418 solution. PC12 ceils were treated with different concentrations of amyloid β-protein (Aβ25-35) for 48 h, to decide the optimal concentration of Aβ25-35 and construct ideal cell model. GPX1/pLNCX/PC12 group, pLNCX/ PC12 group and PC12 group were treated with optimal concentration of Aβ25-35 ,respectively for 48 h, and their absorbance (A) value by MTT conversion was compared among three groups.ResultsCell clone highly expressing GPX1 stably were obtained by G418 selection. The increment of cell inhibition ratio was 24.7 ％ after 20 μmol/L Aβ25-35 treatment for 48 h, compared with control group (P＜0.01). Thus the optimization concentration of Aβ25-35 was 20 μmol/L. After treatment with 20 μmol/L for 48 h, the A value was significantly higher in GPX1/pLNCX/PC12 group than in pLNCX/ PC12 group and in PC12 cells group(0.53±0. 02 vs. 0.44±0.02;0.53±0.02 vs. 0.39±0.07, P＜0.01). Conclusions Transfection of GPX1 recombinant plasmid may protect cell against injury from free radical and reverse the decrease of PC12 cell survival rate impaired by Aβ25-35.

Objective:To mining differential expression genes (DEGs) and establish a regulatory network of dysregulated microRNAs (miRNAs) and messenger RNAs (mRNAs) in biliary atresia (BA) spectrum via bioinforma-tics analysis, and to explore the pathogenesis of BA.Methods:GSE46960 dataset was download from gene expression omnibus (GEO). DEGs between normal liver tissues and BA tissues were analyzed using the GEO2R analysis tool.The functional and pathway enrichment analyses of DEGs were performed utilizing the Database for Annotation, Visualization and Integrated Discovery (DAVID6.8). A protein-protein interaction (PPI) network was constructed using the PPI database (STRING11.0) and Cytoscape_v3.7.1 software, and thus key genes were analyzed.BA-related miRNAs were obtained using the human miRNA disease database (HMDD_V3.0) and target mRNAs were predicted by the miRNA target prediction database (miRDB). The intersection between the predicted target mRNAs and DEGs from the GSE46960 dataset was selected.The regulatory network of miRNA-mRNA was constructed using Cytoscape software.Results:A total of 565 DEGs, including 352 up-regulated ones and 213 down-regulated ones were identified.Among them, up-regulated DEGs were enriched in extracellular matrix(ECM)-receptor interaction, focal adhesion kinase (FAK), Amoebiasis, and the phosphoinositide 3 kinase/protein kinase B(PI3K/Akt) pathway.Down-regulated DEGs were enriched in metabolic signaling, biosynthesis of antibiotics and steroid biosynthesis pathway.From the PPI network, 10 key genes were screened out.A complex miRNA-mRNA regulatory network was constructed based on screened DEGs.Conclusions:Identified DEGs and miRNA-mRNA regulatory network constructed in this study may help clarify the molecular mechanisms of BA.This study provides a new direction to explore promising molecular targets for the diagnosis and treatment of BA.

Non-contrast enhanced MR angiography(NCE-MRA)has been widely used in clinic since advantages of non-radiation and non-contrast media.The image quality of NCE-MRA could be effectively improved using ultra-high field MR scanner,yet 7.0T devices were limited by coils and usually used for cerebrovascular scanning.The invention of 5.0T ultra-high field MR system brings new opportunities for whole body NCE-MRA.The preliminary application of 5.0T whole body NCE-MRA in human body were explored in this article.

DNA methylation is a prevalent epigenetic modification in vertebrates, and it has been shown to be involved the regulation of gene expression and embryo development. However, it remains unclear how DNA methylation regulates sexual development, especially in species without sex chromosomes. To determine this, we utilized zebrafish to investigate DNA methylation reprogramming during juvenile germ cell development and adult female-to-male sex transition. We reveal that primordial germ cells (PGCs) undergo significant DNA methylation reprogramming during germ cell development, and the methylome of PGCs is reset to an oocyte/ovary-like pattern at 9 days post fertilization (9 dpf). When DNA methyltransferase (DNMT) activity in juveniles was blocked after 9 dpf, the zebrafish developed into females. We also show that Tet3 is involved in PGC development. Notably, we find that DNA methylome reprogramming during adult zebrafish sex transition is similar to the reprogramming during the sex differentiation from 9 dpf PGCs to sperm. Furthermore, inhibiting DNMT activity can prevent the female-to-male sex transition, sug-gesting that methylation reprogramming is required for zebrafish sex transition. In summary, DNA methylation plays important roles in zebrafish germ cell development and sexual plasticity.

Ferroptosis is a non-apoptotic regulated cell death caused by iron accumulation and subsequent lipid peroxidation. Currently, the therapeutic role of ferroptosis on cancer is gaining increasing interest. Baicalin an active component in