Objective To evaluate the protective effect and the underlying mechanism of mesenchymal stem cell-derived extracellular vesicle (MSC-EV) on radiation-induced liver injury and liver cell line injury in mouse models. Methods C57BL/6 mice were randomly divided into the blank group, model group and MSC-EV treatment group (treatment group), with 9 mice in each group. AML12 cells were randomly divided into the control group, irradiation group and MSC-EV intervention group (intervention group). Animal and cell models with radiation-induced injury were established by one-time 15 Gy and 6 Gy X-ray irradiation, respectively. At 48 h after irradiation, liver tissues and serum samples of mice were collected and prepared for subsequent experiments. At 15 h post-irradiation, cell experiment was carried out. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and content of malondialdehyde (MDA) in liver tissues and cells were measured. The relative expression levels of interleukin (IL)-1β, IL-6, transforming growth factor (TGF)-β and CXC chemokine ligand (CXCL)10 messenger RNA (mRNA) were detected by real-time fluorescent quantitative polymerase chain reaction (RT-qPCR). Liver tissues were prepared for hematoxylin-eosin (HE) staining to calculate liver pathological injury score. The apoptosis of liver tissues and cells was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) and propidiumiodide (PI) staining, respectively. The expression levels of glutathione peroxidase 4 (GPX4) and ferroptosis suppressor protein 1 (FSP1) proteins were detected by Western blot. The production level of reactive oxygen species (ROS) was detected by dihydroethidine (DHE) staining. The fluorescence intensity of mitochondrial permeability transition pore (mPTP) was determined. Results Compared with the blank group, serum levels of AST and ALT were up-regulated, and the relative expression levels of IL-1β, TGF-β and CXCL10 mRNA in the mouse liver tissues were up-regulated, and MDA content was increased, liver injury score was elevated, cell apoptosis rate was increased, intracellular ROS level was elevated, and the relative expression levels of GPX4 and FSP1 proteins in the mouse liver tissues were down-regulated in the model group, and the differences were statistically significant (all P<0.05). Compared with the model group, serum levels of AST and ALT were decreased, and the relative expression levels of IL-1β, TGF-β and CXCL10 mRNA in the liver tissues of mice were down-regulated, MDA content was declined, liver injury score was declined, cell apoptosis rate was decreased, intracellular ROS level was decreased, and the relative expression levels of GPX4 and FSP1 proteins in the liver tissues of mice were up-regulated in the treatment group, and the differences were statistically significant (all P<0.05). Compared with the control group, cell apoptosis rate was increased, intracellular ROS level was elevated, the fluorescence intensity of mPTP was weakened, the relative expression levels of IL-1β, TGF-β and IL-6 mRNA were up-regulated, MDA content was increased, and the relative expression levels of GPX4 and FSP1 proteins were down-regulated in the irradiation group, and the differences were statistically significant (all P<0.05). Compared with the irradiation group, cell apoptosis rate was declined, intracellular ROS level was decreased, the fluorescence intensity of mPTP was strengthened, the relative expression levels of IL-1β, TGF-β and IL-6 mRNA were down-regulated, MDA content was decreased and the relative expression levels of GPX4 and FSP1 proteins were up-regulated in the intervention group, and the differences were statistically significant (all P<0.05). Conclusions MSC-EV may effectively alleviate radiation-induced liver injury by reducing ferroptosis of liver cells, enhancing antioxidant level and decreasing the production of lipid peroxide, thereby effectively alleviating radiation-induced liver injury.

In order to characterize the immunogenicity and immunoprotection of the Staphylococcus aureus (S. aureus) surface protein Clumping factor A (ClfA), we amplified clfa genes from S. aureus Newman strain, Wood46 strain and HLJ23-1. The clfa gene from Newman strain was subsequently inserted into pQE-30 vector and the recombinant plasmid was transformed into Escherichia coli strain M15 (pREP4). The recombinant ClfA protein was expressed and purified. Then, we immunized mice with the purified recombinant protein. The antibody level and the concentration of cytokines were measured by enzyme-linked immunosorbent assay. Finally, immunized mice were challenged with S. aureus Newman, Wood46 and HLJ23-1. These results suggested that clfa gene sequences were highly conserved, and the recombinant ClfA was expressed correctly with good antigenicity. The antibody titer and the concentration of cytokines in the immunized groups increased significantly (P < 0.05) compared with control, and the mice in the immunized groups were protected against the challenge strains to some extent. These results showed that the ClfA had high immunogenicity and immunoprotective potential.
Animals ; Coagulase ; genetics ; immunology ; metabolism ; Escherichia coli ; genetics ; metabolism ; Immunization ; Mice ; Recombinant Proteins ; genetics ; immunology ; metabolism ; Staphylococcus aureus ; metabolism ; pathogenicity

Objective: To investigate the reversal effects in A549/DDP by standard substances (SS) from Traditional Chinese Medicine. Methods: Cell proliferation assays were performed to investigate the Resistant Index of A549/DDP and its tolerance to selected SS. The working concentrations of SS, IC5 calculated by nonlinear regressions, were applied as reversal doses to investigate the effects. Results: The resistant index of A549/DDP was 31.79. Tetramethylpyrazine and Matrine were well tolerated. Berberine hydrochloride, Dauricine, Oridomin exhibited dose-depend inhibitory effects on A549/DDP cell line. The working concentrations of them could effectively reverse the resistance of A549/DDP cell line to DDP. (P＜0.01) . Conclusion: The selected standard substances from Traditional Chinese Medicine were capable to reverse the resistance of A549/DDP cell line to DDP.

Objective: To compare the measurement accuracy of two⁃dimensional (2D) photography and three⁃di⁃mensional (3D) photography in the analysis of the asymmetric appearance of children with cleft lip and palate and the influence of the severity of asymmetric deformity on the accuracy of facial measurement to guide clinical measurement work Methods: Children with unilateral cleft lip were enrolled in this prospective study. Seven parameters⁃⁃the devia⁃tion of the pronasale, subnasale, and labrale superius, as well as the cleft/noncleft ratio of the width of nostrils, length and height of lateral lips and height of columella⁃were measured with Vernier calipers as the gold standard. Traditional 2D photography and 3D stereophotogrammetry photos were taken and measured. The extent of cleft malformation is indi⁃cated by the ratio of the cleft side to the noncleft side. The error size is represented by the ratio difference between two⁃dimensional photography or stereophotogrammetry with the ratio of the gold standard Results: Thirteen patients were eventually recruited. The measurement results of the ratio of lateral lip height by 2D photography tended to be larger (P＝0.019), and the measurement results of the ratio of columella height tended to be smaller (P＝0.008). The measure⁃ment results of the deviation of the subnasale by stereophotogrammetry tended to be smaller (P＝0.003). The pronasale deviation (P＝0.022) with two⁃dimensional photography, the deviation of the labrale superius (P＝0.025) and the ratio of lateral lip length (P＝0.036) with stereophotogrammetry had a significant negative correlation with the extent of cleft malformation Conclusion Both two⁃dimensional photography and stereophotogrammetry have errors and biases that underexaggerate or overexaggerate the extent of cleft malformation, and some errors may increase with the decrease in the extent of cleft malformation. When applying two⁃dimensional and three⁃dimensional photography to analyze cleft lip and palate deformities, these biases should be considered to evaluate the face more objectively