Objective To investigate diagnostic value of miRNAs for esophageal cancer .Methods Blood samples were obtained from patients with esophageal cancer .MiRNAs including miR-30a ,miR-126a ,let-7b were detected and compared with healthy con-trols .After adjusting smoking and insobriety ,Logistic regression was used to judging which was best for clinical guidance .ROC curve was used to analyzed the clinic value of these miRNAs .Results Age of the two groups had no significant difference(P>0 .05) .The levels of smoking ,alcoholism and family history of cancer in the two groups had significant difference (P<0 .05) .Two groups′miR-30a levels in plasma had no significant differences (P>0 .05) .Let-7b and miR-126a levels in plasma in patients with e-sophageal were significantly higher in healthy volunteers (P<0 .05) .After adjustment the factors of smoking and alcohol ,let-7b lev-els were associated with the risk of esophageal cancer (P<0 .05) .Area under the ROC curve was 0 .712 ,which had a certain esoph-ageal cancer diagnostic performance .Conclusion Plasma let-7b could be treated as a biomarker for the diagnosis of esophageal canc-er.

Objective:To predict the basic physicochemical properties ,structure and function ,and linear B-cell epitopes of the capsid protein VP1 of coxsackievirus A6(CVA6).Methods: The amino acid sequence of the CVA6 VP1 was analyzed using Bioedit software and various online tools including SubLoc ,TargetP and the others from ExPASy Bioinformatics Resource Portal.Results: The CVA6 VP1 protein was a hydrophilic protein with a relative molecular weight of 33.6 kD and an isoelectric point of 7.92.This protein containsed 24 phosphorylation sites , but no signal peptide , transmembrane domains and possible fatty acylation sites.Its secondary structure was characterized by the richest random coils , and 48.52 percent of its amino acid residues exposed at the solution inter-face.Epitope prediction by Bepipred showed a number of potential B cell epitopes in the protein ,the highest antigenicity index among them located in the region of amino acids residue 155-165.Conclusion:The basic physicochemical properties ,structure and function characteristics ,and potential linear B-cell epitopes of CVA 6 VP1 were successfully predicted , which laid foundations for the further study on the protein and the preparation of vaccines and immunological diagnostic reagents for CVA 6 infection.

Objective To investigate the expressions of B7-H1 and PD-1 on peripheral leukocytes from patients with Henoch-Schtmlein purpura(HSP)and their significance.Methods Peripheral leukocytes were obtained from 36 patients with HSP(HSP group)and 24 healthy human controls(control group).Immunofluorescent staining and flow cytometry were used to measure the expressions of B7-H1 and PD-1 on peripheral leukocytes.The expression of both two molecules was compared between the HSP group and control group as well as between patients with Henoch-Sch(o)nlein purpura nephritis(HSPN)(n=9)and those without(n=27).SPSS 12.0 for Windows was used for data analysis.Results The expression rate of B7-H1 on monocytes significantly increased(24.43%±25.79%vs 7.69%±8.31%,t=3.62,P＜0.011),while that of PD-1 decreased(0.84%±1.96%vs 2.28%±1.95%,t=2.78,P＜0.01)in HSP group compared with those in the control group.No significant difference was revealed in the expression of B7-H1 or PD-1 on lymphocytes between HSP group and control group(both P＞0.05).There was a significant increase in the expression of B7-H1 on monocytes(44.81%±12.36%vs 17.63%±25.63%,t=3.05,P＜0.01)and lymphocytes(8.78%±2.10%vs 5.65%±3.96%,t=2.25,P＜0.05)in patients with HSPN compared with those without.Conclusion There is a high expression of B7-H1.but low expression of PD-1 on peripheral blood monocytes from patients with HSP.suggesting that B7-H1 and PD-1 may play a certain role in the Dathogenesis of HSP.

Objective To construct vector expressing soluble mPDL1-hIgGFc and study its effect on the proliferation and apeptosis of cells in vitro. Methods The extrncellular domain of mPDL1 gene was amplified from pmPDL1 vector by PCR and inserted into phIgGFc vector. The recombinant pmPDL1-hIgGFc was transfected into CHO cells by LipofectAMINETM2000, and the transfected cells were named as CHOp. The expression of mPDL1-hIgGFc in the culture supernatants of CHOp was assayed by ELISA and Western blot. The effects of CHOp culture supernatants on mixed lymphocyte culture(MLC) was analysed by Flowm-etry. Results The extracellular domain of mPDL1 gene were obtained from PCR. DNA sequencing and the identification of digestion by HindⅢ and KpnⅠ indicated the recombinant plasmid pmPDL1-hIgGFc was suc-cessfully constructed. ELISA and Western blot analysis proved that the CHOp could express mPDL1-hIgG-Fc. CHOp culture supernatants could inhibit lymphocyte proliferation and induce the apoptosis of the activa-ted T cells in MLC in vitro in a dose-dependent manner. Conclusion The mPDL1-hIgGFc protein could in-hibit lymphocyte proliferation and induce the apoptosis of the activated T cells.

BACKGROUND: The study of cell transplantation to repair injured cardiac muscle and improve cardiac function of dilated cardiomyopathy (DCM) has become a hotspot in recent years. However, the effect of cardiac electrophysiology following transplantation is still unknown.OBJECTIVE: To explore the influence of ailogenic implanted mesenchymal stem cells (MSCs) on cardiac function, structure and electrophysiology of rabbits with DCM.DESIGN, TIME AND SETTING: Randomized controlled animal trial was performed at Electrophysiology Laboratory of Institute of Pediatrics, Chongqing Medical University between January 2004 and May 2006.MATERIALS: Forty-three New Zealand whiterabbits, weighing 3.0-3.5 kg, irrespective of gender, were selected. Adriamycin was produced by Haizheng Medical Products Company of Zhejiang Province, China, No. 050307. The Ultrasonograph SSD-5000 came from Aloka, Japan, and RM6240 multiplying channel electrophysiolograph of Chengdu Instrument Company was applied.METHODS: All animals were randomized into normal group (n=12), cell transplantation group (n=13), and DCM model group (n=13). Except the normal group, adriamycin was applied to create rabbit DCM model, I mg/kg, twice a week for successive 8 weeks. Bone marrow solution was harvested from the remaining 5 rabbits, and MSCs were isolated, amplified and purified using attachment method. Three weeks after modeling, the MSCs were transplanted into left ventricle anterior wall at four sites in cell transplantation group, model group was injected with matching DMEM/FI2 medium, while the normal group was not given any treatment.MAIN OUTCOME MEASURES: At four weeks postoperatively, left ventricular end-diastolic dimension, end systolic dimension,left ventricular ejection fraction, and shortening fraction were monitored by ultrasonograph; the value for monophasic action potential amplitude (MAPA) and the maximum velocity in 0 phase (V,,~), the value for 50% monophasic action potential durations (MAPDs0) and 90% monophasic action potential durations (MAPDg0) were detected by electrophysiolograph. In addition, the cardiac tissues harvested from implanted region were observed by light microscope and electron microscope, and also the expression of cardiac troponin T (cTnT) and connexin 43 (Cx43) was detected through immunohistochemistry.RESULTS: Of 43 rabbits, 9 rabbits each of the transplantation group died of the acute or chronic toxic effects of Adriamycin, finally, 25 rabbits were included in final analysis. Compared with model group, the end systolic dimension was diminished, and the left ventricular ejection fraction and shortening fraction in cell transplantation group were significantly increased (P ＜ 0.05). The MAPDs0 and MAPDgo in cell transplantation group prolonged significantly compared with model group (P ＜ 0.05). In model group,cardiac myocytes appeared mitochondria swelling and hyperplasia, and their sarcomere had different lengths, arranged unevenly,accompanied by abnormal contraction bands. In addition, myolysis was found in parts of myocardium under electron microscope.However, the structural abnormalities in the cell implantation group were less than the DCM model group, and the implanted MSCs could express cTnT and Cx43.CONCLUSION: Allogenic MSCs transplantation can improve cardiac function, lessen structural abnormalities and may inhibit the progression of electrophysiology derangement.

The effectS of survivin antisense RNA on proliferation of leukemia cell line HL-60 and taxol.induced chemotherapy was explorcd.A cDNA fragment of survivin obtained by RT-PCR was inserted into a plamid vector named pcDNA3 in the reverse direction.The vector encoding antisense RNA of survivin was confirmed by restriction enzyme digestion and DNA sequencing.The recombi-nant plasmid was delivered into HL-60 cells by electroporation.Growth curves were plotted based on cell counting.Trypan blue dye exclusion assay and MTT assay were carried out after the cells were incubated with taxol.DNA gel electrophoresis and nuclear staining were performed for cell apoptosis assay.The correct construction of the recombinant plasmid has been identificd bv restriction enzy.me digestion and DNA sequencing.A stable down.regulation has been achieved in HL-60 SVVas cells after G418 selection.Compared tO HL-60 cells.the proliferation of HL-60 SVVaS cells was signifi.cantly inhibited(P＜0.05).Cytotoxicity assays indicated that IC50 of HL-60 SVVas for taxol was rela-tively lower than controls(P＜0.01).Apoptosis assays revealed that taxol-induced apoptosis was de-tected in HL-60 sVVas cells incubated with 50 ng/ml taxol for 12 h,while in HL-60 cells incubated with 100 ng/ml taxol for 72 h.It was suggested that Survivin antisense RNA could inhibit the prolif-eration of HL-60 cells and enhance taxol-induced apoptosis in HL-60 cells.which may lay an ex-perimental foundation for further research on gene therapy in leukemia.

Summary: The purpose of this study was to construct expression vectors of idiotype (Id) Smlg in patients with B-chronic lymphocytic leukemia and to express them in E.coli to obtain recombinant Id,and to investigate the effect of the protein on the proliferation and secretion of IL-2 and IFN-γ of stimulated peripheral blood mononuclear cells (PBMC) in vitro. Light chain gene and Fd fragment of heavy chain gene were inserted into fd-tet-DOG2 vector to construct fd-tet-DOG2-Fab. Fab gene was further cloned into expression vector pHEN2 to construct the soluble expression vector pHEN2-Fab. After induction by IPTG, Fab protein was purified by Ni-NTA-chromatography. MTT was used to determine the effects of purified protein on the proliferation of stimulated PBMC in vitro and the concentrations of IL-2 and IFN-γ in the culture supernatants were detected by ELISA. The results showed that recombinant pHEN2-Fab expression vector was constructed successfully. Fab protein was expressed in positive clone after induced by 1PTG and two specific bands at 24-25 kD position were observed by SDS-PAGE electrophoresis. Proliferation of PBMC could be induced by purified Fab and the concentrations of IL-2 and IFN-γ, in culture supernatants were increased significantly after induction. It was suggested that the expression vector of SmIg Fab fragment was constructed successfully, and expressed and secreted from E. Coli. The Fab protein could induce proliferation of PBMC and promote secretion of IL-2 and IFN-γ.

To obtain single chain variable fragment (scFv) and bivalent single chain variable fragment (bsFv) against transferrin receptor, up-stream and down-stream primers were designed according to the complemenary sequences of FR1 region of variable heavy (VH) and FR4 of variable light (VL), respectively, which contained inter-linker G4S and the restriction endonuclease Sill, AscI and NotI. Two pieces of scFv fragments were first amplified through PCR and then inserted into plasmid pAB 1, which could express scFv protein once induced by IPTG in the host bacteria. To express scFv and bsFv, E. coli TG1 was cultured in LB broth and was induced by IPTG The restriction enzyme digestion map and DNA sequencing demonstrated that scFv and bsFv genes were successfully inserted into the expression plasmid. SDS-PAGE and Western blotting revealed the protein band at 35kD and 60kD, which were consistent with the molecular weight of scFv and bsFv respectively.Flow cytometry showed that scFv and bsFv harbored the specific binding activity with TfR expressed in various tumor cells, and the avidity of bsFv was higher than that of the parent scFv.

The purpose of this study was to construct expression vectors of idiotype (Id) SmIg in patients with B-chronic lymphocytic leukemia and to express them in E.coli to obtain recombinant Id, and to investigate the effect of the protein on the proliferation and secretion of IL-2 and IFN-gamma of stimulated peripheral blood mononuclear cells (PBMC) in vitro. Light chain gene and Fd fragment of heavy chain gene were inserted into fd-tet-DOG2 vector to construct fd-tet-DOG2-Fab. Fab gene was further cloned into expression vector pHEN2 to construct the soluble expression vector pHEN2-Fab. After induction by IPTG, Fab protein was purified by Ni-NTA-chromatography. MTT was used to determine the effects of purified protein on the proliferation of stimulated PBMC in vitro and the concentrations of IL-2 and IFN-gamma in the culture supernatants were detected by ELISA. The results showed that recombinant pHEN2-Fab expression vector was constructed successfully. Fab protein was expressed in positive clone after induced by IPTG and two specific bands at 24-25 kD position were observed by SDS-PAGE electrophoresis. Proliferation of PBMC could be induced by purified Fab and the concentrations of IL-2 and IFN-gamma in culture supernatants were increased significantly after induction. It was suggested that the expression vector of SmIg Fab fragment was constructed successfully, and expressed and secreted from E. coli. The Fab protein could induce proliferation of PBMC and promote secretion of IL-2 and IFN-gamma.

To obtain single chain variable fragment (scFv) and bivalent single chain variable fragment (bsFv) against transferrin receptor, up-stream and down-stream primers were designed according to the complementary sequences of FR1 region of variable heavy (VH) and FR4 of variable light (VL), respectively, which contained inter-linker G4S and the restriction endonuclease SfiI, AscI and NotI. Two pieces of scFv fragments were first amplified through PCR and then inserted into plasmid pAB1, which could express scFv protein once induced by IPTG in the host bacteria. To express scFv and bsFv, E. coli TG1 was cultured in LB broth and was induced by IPTG. The restriction enzyme digestion map and DNA sequencing demonstrated that scFv and bsFv genes were successfully inserted into the expression plasmid. SDS-PAGE and Western blotting revealed the protein band at 35kD and 60kD, which were consistent with the molecular weight of scFv and bsFv respectively. Flow cytometry showed that scFv and bsFv harbored the specific binding activity with TfR expressed in various tumor cells, and the avidity of bsFv was higher than that of the parent scFv.
Base Sequence ; Cloning, Molecular ; Escherichia coli/genetics ; Escherichia coli/metabolism ; Genetic Vectors/genetics ; Hep G2 Cells ; K562 Cells ; Molecular Sequence Data ; Receptors, Transferrin/*immunology ; Recombinant Fusion Proteins/biosynthesis ; Recombinant Fusion Proteins/genetics ; Single-Chain Antibodies/*biosynthesis ; Single-Chain Antibodies/genetics