BACKGROUND:Currently, there is a lack of efficient, non-invasive way to transplant stem cels to the target organ or tissue. Exploring a way to guide targeting transplantation of stem cels and to improve the efficiency of stem cel homing is now one of focuses in the field of stem cels research.
OBJECTIVE: To establish a simple and feasible method to chemicaly modify the cel surface using biotin-streptavidin reaction system, and to evaluate the efficiency of this method to label bone marrow mesenchymal stem cels (BMSCs) and its effects on cel biological functions.
METHODS: Passage 3 BMSCs were obtained by whole bone marrow culture method and verified by flow cytometry. Biotin, streptavidin, sulfonated biotin-N-hydroxy-succinimide were used to equip the adhesion molecule ligand, sialyated LewisX (SLeX), to the BMSCs surface. The labeling rate of BMSCs was assessed using fluorescence microscope, the vitality of BMSCs was evaluated by trypan blue staining, and the proliferation of BMSCs was evaluated by cel counting kit-8 assay. Adipogenic and osteogenic inductions were used to evaluate the effect of the method on the multi-differentiation function of BMSCs.
RESULTS AND CONCLUSION: After culture for 2 weeks, passage 3 BMSCs were obtained and confirmed by expressing CD90, CD29 and lack of CD34, CD45. Biotin, streptavidin, sulfonated biotin-N-hydroxy-succinimide were successfuly used to equip sialyated LewisX (SLeX) to the BMSCs surface and had minor effects on the vitality, proliferation, and differentiation of BMSCs. This method was simple for surface modification and had a high modification rate of 88%. The homing of BMSCs modified by this method to the target organ or tissue could be greatly enhanced. Therefore, this method potentialy could have extensive and important applications.

Objective To explore the mechanism of anti-tumor effects of transferring tumor-specif-ic lymphocytes obtained from pre-immunized BALB/c mice with inactive rolL-21 tumor vaccine (mIL-21-Sp2/0)to syngeneic mice, associated with mIL-21 tumor vaccine immunization, in the condition of cyclo-phosphamide (Cy)-induced lymphopenia. Methods Activated lymphocytes of spleen and lymph nodes ob-tained from pre-immunlzed syngeneic mice with irradiated mIL-21-Sp2/0 cells were infused into BALB/cmice treated with Cy 2 days before, subsequently vaccinated with mlL-21 tumor vaccine, after 7 days, chal-lenged with Sp2/0 tumor cells, observed the growth of tumor of mice. T lymphocyte subsets differentiation was measured by flow cytometry (FCM) analysis. The proliferation and cytotoxie activities of activated lym-phocytes were analyzed by FCM, respectively, staining with CFSE and 7-AAD. The number of IFN-γ-secre-ting cells was evaluated by ELISPOT. Results The lymphopenic mice were transferred with activated lym-phocytes and inoculated with raiL-21 tumor vaccine might provide superior anti-tumor immunoprotection, re-tard tumor growth of the mice. The proliferating capabilities and killing rate of transferred tumor Ag-specific lymphocytes enhanced obviously, the number of IFN-γ-secreting cells was significantly higher compared with the control groups. Conclusion Under Cy-induced lymphopenia condition, tumor Ag-specific lymphocytes sensitized by raiL-21 tumor vaccine were transferred to mice and immunized with mlL-21 tumor vaccine at the same time, benefit the proliferation of transferred effective cells and immune cells itself, assist to form and sustain special anti-tumor effects.

Objective To analyze the epidemiologic characters of human plague from Rattus flavipectus plague natural foci in Yunnan Province from 1986 to 2006 and to provide references for prevention and control strategy.Methods Data were collected and analyzed on epidemic situation of human plague in the past twenty-one years.Results From 1986 to 2006,the total human plague cases from Rattus flavipectus plague natural foci in Yunnan were 507,accounted for 59.5%(507/866)of the total cases in the whole country.There were three peaks of human plague outbreak in 1990,1996 and 2000.The number of annual cases were 73,88 and 122,accounting for 97.3%(73/75),89.8%(88/98),48.0%(122/254)of the total cases in the whole country respectively.The epidemic areas were mainly located in the west,southwest and southeast pans of Yunnan,but the number of cases changed with year in different prefectures(or cities).Seasonal pattern analyses revealed that the epidemic could occur in whole year,with a peak period through July to November,especially September.There were different prevalence of plague cases in age and professions,which related to the chance of contact with infected animals and infectious fleas.All human plague cases were primary bubonic plague.Conclusions The results suggested that there were clear epidemic characteristics for human plague for Rattus flavipectus plague natural foci in Yunnan.In order to control human plague effectively,it was necessary to reinforce surveillance and warning system to diminish the outbreak of human plague.

Objective To investigate the effect of video -assisted thoracoscopic surgery (VATS)and conventional thoracotomy in treatment of thoracic esophagus cancer,to provide the reference for clinical.Methods 90 cases of thoracic esophageal cancer in our hospital from January 2012 to January 2015 were chosen as the research subjects.They were randomly divided into observation group(application of VATS treatment)and the control group (application of traditional open chest surgery).The quantity difference,chest drainage,hospitalization time,complica-tions,recovery conditions and other indicators of bleeding were compared in the two groups.Results The operation time of the observation group[(267.6 ±76.5)min]was shorter than that of the control group[(324.4 ±87.6)min]. The amount of intraoperative bleeding[(235.3 ±79.5)mL],drainage volume[(327.5 ±95.2)mL]of the observation group were less than the control group[(398.2 ±98.3)mL and (752.6 ±156.4)mL].Postoperative hospitalization time[(12.2 ±3.2)d]of the observation group was shorter than the control group[(15.8 ±4.4)d].The differences were statistically significant (t =3.276,8.644,15.575,4.439,all P <0.05).There were no significant differences between two groups in recurrence and metastasis rate,mortality rate and total survival rate (χ2 =0.123,0.212, 0.212,all P >0.05).The complication rate of the observation group was lower than that of the control group,the difference was statistically significant (χ2 =4.865,P <0.05).Conclusion In the treatment of thoracic esophageal carcinoma,VATS and conventional thoracotomy surgery has good effect,and VATS has small injury,less complication.

Bioimprinting is a new developed technique to improve the characteristics of enzymes.Bioimprinting by lauric acid was conducted to improve the esterification activity of lipase PS in sol-gel immobilization process with methyltrimethoxysila(MTMS) and tetramethoxysila(TMOS) as the precursors.Results generated by checking the esterification activity and scanning electron microscope showed that bioimprinting can enhance the specific activity and thermal stability of lipase PS.The bioimprinting system was optimized by orthogonal experiment,and the optimal condition for lipase bioimprinting is water/silane molar ration(R) 12,polyethylene glycol(PEG) 120?l,and lauric acid 0.15 mmol.Compared with the free enzyme and the non-imprinted enzymes,the specific activity of imprinted enzymes has been improved 44.3 fold and 2.4 fold,respectively.Imprinted lipase show better thermal stability,and the relative activity is 58% after incubated in 80 ℃ for 0.5 h,while no activity was detected for the free enzyme.

Aim To study inhibitory effect of 5-fluorouracil encapsulated by galactosylceramide liposomes (5-Fu-GCL)on 5-Fu-resistent HepG_2 cells and its mechanisms. Methods Inhibitory effect of 5-Fu-GCL on established model of 5-Fu-resistant HepG_2 cells was assessed with MTT assay in vitro. The concentration-time course of 5-Fu-GCL in intracellular fluid was detected with high performance liquid chromatography (HPLC). Thymidylic acid synthase (TS) expression was observed with immunohistochemical method,and NO content was determined with chemical method. Results Obvious inhibitory effects of 5-Fu-GCL (75,150,300,600,1200?mol?L-1) on 5-Fu-resistant HepG_2 cells were observed with IC_ 50 of 158.6 ?mol?L-1,far lower than that of free 5-Fu (400.9 ?mol?L-1). 5-Fu-GCL (300 ?mol?L-1) inhibited 5-Fu-resistant HepG_2 cells in a time-dependent manner,and the inhibitory effect of 5-Fu-GCL was stronger than that of free 5-Fu during 12～48 h. Compared with free 5-Fu,5-Fu-GCL (300 ?mol?L-1) increased the content of intracellular fluid in 5-Fu-resistant HepG_2 cells. 5-Fu-GCL(62.5,300,1200 ?mol?L-1) not only inhibited the expression of TS,but also increased the production of NO in 5-Fu-resistant HepG_2 cells,and these effects of 5-Fu-GCL(300,1200 ?mol?L-1) were stronger than those of free 5-Fu. Conclusion 5-Fu-GCL has inhibitory effect on 5-Fu-resistant HepG_2 cells. The effect may be related to the increased concentration of 5-Fu-GCL in intracellular fluid,inhibited expression of TS and increased production of NO.

0.05).There was significant difference between normal control group and group A and B(P0.05 ).Neuron counting was significantly higher in group B than that in group A 4 weeks after treatment(P

Objective To investigate the effect of high power microwave(HPM) irradiation on neuropeptide Y (NPY) and neural nitric oxide synthase (nNOS) expression in the cerebral cortex and hippoeampus of Wistar rats. Methods A total of 110 Wistar rats were used for this study.Three groups of 30 Wistar rats were exposed to HPM irradiation at intensities of 3,10,30 and 100 mW/cm~2,respectively.Twenty rats served as controls and were ex- posed to sham HPM irradiation.At 6 h,and at 1,3,7,14 and 28 d after irradiation,five rats from each group were sacrificed,and their cerebral cortices and hippocampi were harvested.HE staining was used to highlight any change in the structure of the cerebral cortex or hippocampus.Immunohistochemistry techniques and image analysis were used to study the changes in NPY and nNOS expression.Results 10 to 100 mW/cm~2 HPM irradiation caused pyc- nosis and deep staining of some neurons in the cerebral cortex and hippocampus.The increase in nNOS expression and decrease in NPY expression observed were significant at 3 days after irradiation.Conclusion HPM irradiation can induce injury in neurons of the cerebral cortex and hippoeampus,and abnormal NPY and nNOS expression.

OBJECTIVETo investigate the effects of Salvianolic acid B preconditioned endothelial progenitor cells (EPCs) on the Nkx2.5 and GATA-4 gene expressions at the early stage of cell differentiation of bone mesenchymal stem cells (BMSc) transplanted into infarcted myocardium, in order to find out the best synergism for co-transplantation of the two kinds of cells.

METHODSBMSc and EPCs of rats were isolated and cultured, and rats were modeled into acute myocardial infarction (AMI) by left coronary artery ligation. Then the EPCs preconditioned with different concentrations of Salvianolic acid B and BMSc or DMEM medium were implanted into heart ischemia area. Expressions of Nkx2.5 and GATA-4 mRNA expressions in myocardium were detected by Real-time RT-PCR 4 weeks later.

RESULTSCompared with those in the non-implanted model rats' myocardium, the gene expression of Nkx2.5 and GATA-4 mRNA were significantly higher in all the transplantation receptive groups, comparisons between the implanted groups showed that the highest value of expressions (2. 654 +/- 0.606 of Nkx2.5 and 1.573 +/- 0.372 of GATA-4) displayed in the group contained more EPCs, for 8-fold to BMSc in volume.

CONCLUSIONBMSc can differentiate into cardiac muscle like cells, and condition of their differentiation is related with the degree of the internal environment improved.

Animals ; Benzofurans ; pharmacology ; Cells, Cultured ; Endothelial Cells ; cytology ; drug effects ; transplantation ; Gene Expression ; drug effects ; Male ; Mesenchymal Stem Cell Transplantation ; Myocardial Infarction ; metabolism ; therapy ; Myocardium ; metabolism ; Random Allocation ; Rats ; Rats, Wistar ; Stem Cell Transplantation ; Stem Cells ; cytology ; drug effects

OBJECTIVETo compare the anti-rotation biomechanical performances of wire and various cable fixation devices currently used in the posterior Brooks instrumentation for atlantoaxial instability.

METHODSIn this experiment,six specimens of the atlantoaxial complex (Occipital-C3) were used. The models of the normal complex,unstable complex (type II odontoid fracture) and fixed complex were established. On the WD-5 mechanics experimental machine,the parameters including the strength and rigidity of anti-rotation were quantified for the normal complex (group N),the atlantoaxial instability complex (group M), the new type Titanium cable (group A), Atlas titanium cable (group B), Songer Titanium cable (group C), stainless wire(group D).

RESULTSThe max strength of A, B, C, D groups was 12.5, 11.3, 11.52, 11.55 N x m respectively, the max rigidity was 58.81, 53.17, 54.11, 54.35 N x cm/deg respectively. The strength and rigidity of anti-rotation, compare to the unstable atlantoaxial complex which were fixed by the new double locking Titanium cable fixation system were superior to those of normal complex, instability complex, Songer or Atlas Titanium cable (P < 0.05).

CONCLUSIONHaving been changed the locking method, the anti-rotation biomechanical characteristics of the new type double locking Titanium cable fixation system are superior or similar to the traditional Songer or Atlas Titanium cable.

Atlanto-Axial Joint ; physiopathology ; surgery ; Biomechanical Phenomena ; Bone Wires ; Humans ; Joint Instability ; physiopathology ; surgery ; Orthopedic Fixation Devices ; Rotation