OBJECTIVETo investigate the effect of human caudal-related homeobox 2 (Cdx2) gene expression on human gastric carcinoma cell line MGC-803.

METHODSpCMV-Cdx2-HA eukaryotic expression plasmid was constructed by using DNA recombinant method. The MGC-803 cells were divided into 4 groups: non-transfected, transfected with pCMV-HA, transfected with pCMV-GAPDH-HA, transfected with pCMV-Cdx2-HA. Cdx2 gene and its protein expression was detected by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot techniques respectively. The effects of Cdx2 overexpression on the growth of MGC-803 cells in vitro was assessed by measuring MTT, flow cytometry and transmission electron microscopy analysis.

RESULTSIn MGC-803 cells transfected with pCMV-Cdx2-HA, cell proliferation was significantly suppressed, the cells was ultrastructurally destroyed, cell cycle progression was blocked in G0/G1 and apoptosis rate was higher (P<0.05) in comparison with non-transfected cells or cells transfected with empty vector.

CONCLUSIONIt indicated that Cdx2 gene can suppress the growth of gastric carcinoma and may save as a novel therapeutic target.

Apoptosis ; Cell Cycle ; Cell Line, Tumor ; Genetic Vectors ; Homeodomain Proteins ; genetics ; metabolism ; Humans ; Plasmids ; genetics ; RNA, Messenger ; genetics ; Stomach Neoplasms ; metabolism ; pathology ; Transfection

PURPOSEThis study aims to explore the biomechanical mechanism of lower limb injuries to the driver by establishing a finite element (FE) simulation model of collisions.

METHODSFirst a minibus FE model was integrated with a seat belt system. Then it was used to rebuild two collisions together with the total human model for safety (THUMS) provided by Toyota Motor Corporation: a rear-end collision between a minibus and a truck and a head-on collision of a minibus to a rigid wall. The impact velocities of both collisions were set at 56 km/h. The vehicle dynamic response, vehicle deceleration, and dashboard intrusion in the two collisions were compared.

RESULTSIn the minibus rear-end truck collision, the peak values of the von Mises equivalent stress at the tibia and the femur were 133 MPa and 126 MPa respectively; while in the minibus head-on rigid wall collision, the data were 139 MPa and 99 MPa. Compared with the minibus head-on rigid wall collision, the vehicle deceleration was smaller and the dashboard intrusion was larger in the minibus rear-end truck collision.

CONCLUSIONThe results illustrate that a longer dashboard incursion distance corresponds to a higher von Mises equivalent stress at the femur. The simulation results are consistent with the driver's autopsy report on lower limbs injuries. These findings verify that FE simulation method is reliable and useful to analyze the mechanisms of lower limb injuries to the driver in minibus frontal collisions.

Accidents, Traffic ; Automobile Driving ; Biomechanical Phenomena ; Finite Element Analysis ; Humans ; Lower Extremity ; injuries

OBJECTIVETo investigate the feasibility of human bone marrow mesenchymal stem cells (hBMSCs) in vitro differentiation into vascular smooth muscle cells with induction of platelet-derived growth Factor BB (PDGF-BB).

METHODSBone marrow mesenchymal stem cells of adult healthy donors were separated from iliac crest aspiration and expanded in DMEM-LG medium. Cells at passage 1 were transferred to EGM-2 medium containing PDGF-BB (20 ng/ml) and cultured for 14 days. The expression of SM alpha-actin, SM calponin, SMMHC and SM 22alpha were detected by immunofluorescence and observed with fluorescence microscope. mRNA expression of SMalpha-actin, SM calponin, SMMHC as well as SM 22alpha was analyzed by RT-PCR. The method of Western-Blot was applied to determine protein expression of SM 22alpha. Cells with induction were observed for the expression of SM alpha-actin,SM calponin,SMMHC by FACs analysis.

RESULTSWith the induction of PDGF-BB, the morphology of cells changed to a spindle fibroblastic appearance. By fluorescence microscope observation, expression of SM alpha-actin, SM calponin and SMMHC was found intracellularly in PDGF-BB treated hBMSCs at 14 days. Western-Blot detection confirmed SM 22alpha expression by 14 days induction. RT-PCR of characteristic vascular smooth muscle cells related genes, such as SM alpha-actin, SM calponin, SMMHC and SM 22alpha revealed differentiation of vascular smooth muscle cells phenotype in monolayer culture upon stimulation with PDGF-BB for 14 days. The positive expression of SM alpha-actin, SM calponin and SMMHC in induced cells was significantly higher than that in non-induced cells (P < 0.05, n=3).

CONCLUSIONThese results suggested hBMSCs could be differentiated into vascular smooth muscle cell phenotype with PDGF-BB induction in vitro.

Adult ; Bone Marrow Cells ; cytology ; Cell Differentiation ; drug effects ; Cells, Cultured ; Humans ; Mesenchymal Stromal Cells ; cytology ; Muscle, Smooth, Vascular ; cytology ; Platelet-Derived Growth Factor ; pharmacology ; Proto-Oncogene Proteins c-sis ; Tissue Engineering ; methods

Objective:To identify the transdermal constituents of Euodiae Fructus and predict its molecular mechanism in treating diarrhea by transdermal drug delivery. Method:Ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry （UPLC-Q-TOF-MS） and integrated pharmacology methods were used. The rapid identification of transdermal constituents of Euodiae Fructus was realized by the means of comparison of reference substances， analysis of UNIFI system and mass spectrometry. On this basis， Integrative Pharmacology-based Research Platform of Traditional Chinese Medicine （TCMIP） v2.0， SymMap， DisGeNET databases and literature were used to collected potential targets of transdermal constituents of Euodiae Fructus and targets for diarrhea-related diseases. The disease targets and drug targets were topologically analyzed to obtain the core targets， which were used for the Gene Ontology （GO） function and Kyoto Encyclopedia of Genes and Genomes （KEGG） pathway enrichment analysis. Finally， Cytoscape 3.6.0 was used to build up a network of transdermal constituents-core targets-key pathways. Result:A total of 19 chemical constituents were speculatively identified from Euodiae Fructus extract， including quinolone alkaloids， limonins， indole alkaloids， organic acids and sterols. A total of 174 core targets of Euodiae Fructus for treating diarrhea were obtained by a topology analysis， signaling pathways of inflammatory response， cell proliferation， nutrient regulation and energy metabolism， signal transduction， bacterial infection were obtained through the analysis of KEGG enrichment. Conclusion:In this study， the transdermal constituents of Euodiae Fructus are identified for the first time， they can participate in the regulation of intestinal inflammation， maintain the integrity of intestinal mucosa， repaire and adjust the metabolism of the body by acting on Rac protein family， phosphatidylinositol 3-kinase， cytochrome P450 enzymes and aldo-keto reductase， respectively. In general， the molecular mechanism of Euodiae Fructus in the treatment of diarrhea is preliminarily elucidated.