Objective To assess the accuracies and feasibility of spine surgery assisted by different types of navigation system.Methods In experiment study,40 human cadaveric cervical spines were employed and 3.5 mm screws were placed into the C 3 to C 7 pedicles following five kinds of insertion techniques:blind screw placement(Group 1),assisted by X-ray fluoroscopy(Group 2),assisted by virtual fluoroscopy navigation system(Group 3),assisted by CT-based navigation system(Group 4),assisted by Iso-C 3D navigation system(Group 5).Thereafter,cortical integrity of every sample was examined by anatomic dissection.In clinical study,163 cases of spine operations assisted by different types of navigation were reviewed.The accuracies of screw placement were evaluated by postoperative CT or Iso-C 3D scan.Results In experiment study,there were 398 pedicles inserted.Group 1,the average operation time per sample was 27 minutes;36.3% of the screws were excellent,26.3% good,and 37.5% bad.Group 2,the average operation time was 112 minutes;44.9% excellent,37.2% good,and 17.9% bad.Group 3,the average operation time was 69 minutes;42.5% excellent,45.0% good,and 12.5% bad.Group 4,the average operation time was 98 minutes;87.5% excellent,12.5% good.Group 5,the average operation time was 91 minutes;90% excellent,10% good.In clinical study,272 screws inserted with virtual fluoroscopy navigation system,89.3% excellent,10.7% good.571 screws inserted with CT-based navigation system,84.9% excellent,14.4% good,0.7% bad.142 screws inserted with Iso-C 3D navigation system,95.8% excellent,4.2% good.Conclusion Computer-assisted navigation system enhances accuracies and further improves the safety of spine surgery,especially utilizing CT-based navigation system and Iso-C 3D navigation system.Iso-C 3D navigation method is better than the other two navigation methods.

Objective To study some biological properties of mouse bone marrow stromal cells(MSCs)and their ability to differentiate endothelial cells and surviving ability in ischemic tissue,and provide an experimental foundation for applying MSCs to ischemic repair.Methods After the tibias and femurs were dissected from 5-to 6-week-old mice from Jan.2005 to Nov.2005,the marrow was flushed out with ice-cold DMEM/F12 medium.The mononuclear cells of the marrow were obtained with density gradient centrifugation and the plated and cultured in DMEM/F12 medium.The cultured cells in vitro were induced with endothelial cell growth supplement.The ability of MSCs was also was examined in ischemic tissue.Results The adherent fibroblast-shaped cells approached confluence in single layer 12~16 d after plating.The cultured MSCs in vitro differentiated into endothelium.Numerous scattered DAPI-labeled cells were found in the specimen seven days after implantation,and hematoxylin and eosin staining of the adjacent section showed concordance between dense hematoxylin staining and presence of DAPI epifluorescence,and there was no obvious inflammatory response.Conclusion The subcultured MSCs possess potential to differentiate into endothelial cells.MSCs show stable growth in vitro,easy survival in the subculture and rapid proliferation in present culture condition.MSCs may be used in therapy for myocardium ischemia.

Tetrabromobisphenol A(TBBPA)is supposed to have potential thyroid disrupting activities due to its similar structure to thyroid hormones.TBBPA has been proved to show thyroid disrupting effects in vivo and in vitro studies.TBBPA might disrupt thyroid hormone system through transthyretin- and thyroid receptor-mediated pathways.The ability of TBBPA inducing the production of reactive oxygen species might be the extension of its thyroid disrupting activities.The thyroid disrupting effects of TBBPA might be closely related to its oxidative stress,reproduction toxicity and neurotoxicity.More experiments are required for the effects of TBBPA on the aquatic and amphibian animals.

Objective:To investigate biomechanical changes of mandible in the impact injure simulated by finite element method (FEM).Methods:Mimics and Comsol software were used to build a FEM of human craniofacial bone based on CT scan data of a normal adult.LS-DYNA and Hypermesh software were used to simulate the impact with different quality,velocity and angulation pro-duced injures of human mandible,the biomechanical parameters of the mandible in the impact injury process were analysed.Results:A FEMof human maxillofacial bone was established,and the dynamic process of different impact force produced damage was simula-ted.Mandibular chin,angle and condylar neck was the stress concentrated area in the process of mandible injury.There was higher stress peak at the site which was closer to the impact position,the stress peak arrival time was also earlier.When the impactor with the same quality,the bigger the velocity,the greater the stress peak.When the impactor with the same velocity,the bigger the quali-ty,the greater the stress peak.When the impactor with the same velocity and quality,there was greater stress peak under the impact to mandible from angulation of 0 degree.Stress transfered to the surrounding bone from the impact position radially and gradually re-duced.The bone area with small cross-section was prone to high stress and more serious damage.Conclusion:The quality,the ve-locity,the impact angle and the impact site are the factors affecting the severity of impact injury.

Objective:To observe influence of simvastatin on p 27 protein (cyclin‐dependent kinase inhibitor ) expres‐sions of vascular smooth muscle cells (SMC) and endothelial cells (EC) in rats for screening new generation coating drugs of eluting stents .Methods :Primary aortic SMC and EC of rat were isolated and cultured by methods of adher‐ent and enzymatic digestion respectively .Which were inoculated on fibronectin -coated culture plates .α smooth muscle actin immunofluorescence staining was used to identify SMC ,and von Willebrand factor (vWF) immunofluo‐rescence staining was used to identify EC .SMC and EC were cultured for 24h with different concentrations of simv‐astatin (0.01 ,0.1 ,1 and 10 μmol/L) ,then Western blot was used to measure p27 protein expression .Results:Compared with blank control group ,0.01μmol/L simvastatin had no significant influence on p 27 protein expression of SMC ,but 0.1 ,1 and 10 μmol/L simvastatin significantly raised p27 protein expression of SMC [ (0.53 ± 0.08) vs .(0.86 ± 0.05) ,(1.20 ± 0.05) ,(1.60 ± 0.04)] , P< 0.01 all .Besides ,different concentrations of simvastatin had no significant influence on p27 protein expression of EC , P> 0.05 ,indicating that simvastatin only dose‐de‐pendently promoted p27 protein expression of SMC .Conclusion:Simvastatin dose -dependently promotes p27 pro‐tein expression of vascular smooth muscle cells without affecting p 27 protein expression of endothelial cells .So local application of simvastatin may inhibit restenosis and promote reendothelialization of injured vessels .

BACKGROUND:Autologous split-thickness skin grafting is the main therapy for burn repair at functional sites, which has achieved certain effects, but there are stil some deficiencies, such as poor texture, stiffness and poor toughness, as wel as severer hyperplasia that is easy to result in contracture deformity and poor functional recovery. OBJECTIVE: To analyze the clinical efficacy of skin co-transplantation on burn repair at functional sites. METHODS:Sixty patients with burns at functional sites (n=84) were randomized into two groups: co-transplantation of acelular dermis and autologous split-thickness skin in experimental group and autologous split-thickness skin graft in control group. Survival rate of skin flap and rate of secondary operation were compared between two groups. At 1 month after transplantation, Vancouver Scar Scale was used to assess skin color, thickness, blood vessel distribution and flexibility, and meanwhile, the severity of scar was determined. RESULTS AND CONCLUSION:The survival rate of skin flap was significantly higher in the experimental group than the control group (93%vs. 70%,P < 0.05), and the rate of secondary operation was significantly lower in the experimental group compared with the control group (0vs. 13%,P < 0.05). At 1 month after transplantation, scores on the skin color, thickness, blood vessel distribution and flexibility were al lower in the experimental group than the control group (P < 0.05), but the incidence of mild hyperplasia in the experimental group was significantly higher than that in the control group (52% vs. 29%,P < 0.05). These findings indicate that co-transplantation of acelular alogeneic dermis and autologous split-thickness skin for burn repair at functional sites can effectively enhance the survival rate of skin flap, reduce the rate of secondary operation, contribute to wound healing and reduce the severity of hyperplasia.

Objective To construct the bait expression plasmid pGBKT7-GR of glucocorticoid receptor(GR)binding domain.Methods The fragments of GR binding domain was amplified by RT-PCR,and then was cloned into pMD18-T.After being verified by sequencing,it was subcloned into the bait expression vector pGBKT7.Then the bait vector pGBKT7-GR was transformed into AH109 yeast cells and the expression of the bait protein was analyzed by Western blot.Toxicity and self-activation of the bait protein were detected.Results GR binding domain was amplified and cloned into pMD18-T and pGBKT7 successfully.The bait vector was transformed into AH109 yeast cells successfully,without toxicity or self-activation.The expression of the bait protein was confirmed by Western blot.Conclusion The successful construction of bait expression vector of glucocorticoid receptor binding domain lays the foundation for constructing small molecule ligand yeast three-hybrid system.

Human Interleukin-11 (hIL-11) is a multifunctional cytokine which plays an important role in regulating the proliferation and differentiation of cells in the hematopoeitic,lymphoid system etc. To obtain the IL-1 1 cDNA, a primary culture of Chinese fetal lung fibroblast was prepared from fresh tissue. Then the human IL-11 cDNA without the N-terminal signal peptide sequence was cloned by RT-PCR from the cells induced by PMA. The sequnce indicated that there are three bases different from those previously reported,but with no change of the amino acids. The cDNA was inserted into the 3′ end of trxcA gene in thioredoxin gene fusion expression system pTRXFUS to construct the trxA and hIL-1 1 fusion expression vector, and expressed in E. coli. The fusion hIL-11 accounts for more than 20 % of the total bacteria proteins.The expression product is present in soluble forms and has the full biological and immunological activities.

The fruit of Pandanus tectorius (PTF) has a long history of use as a folk medicine to treat hyperlipidemia in Hainan province, South China. Our previous studies have shown that the n-butanol extract of PTF is rich in caffeoylquinic acids and has an adequate therapeutic effect on dyslipidemic animals induced by high-fat diet. In this work, seven caffeoylquinic acids isolated from PTF were screened for the lipid-lowering activity in HepG2 hepatoma cells. Oil-Red O staining, microscopy and intracellular triglyceride (TG) and total cholesterol (TC) quantification showed that 3-O-caffeoylquinic acid (3-CQA), 3, 5-di-O-caffeoylquinic acid (3,5-CQA), and 3,4,5-tri-O-caffeoylquinic acid (3,4,5-CQA) significantly inhibited lipid accumulation induced by oleic acid and decreased intracellular levels of TC and TG in a dose-dependent manner. These three caffeoylquinic acids showed no significant cytotoxicity at concentrations of 1 -50 μmol x L(-1) as determined by MTT assay. Realtime quantitative PCR revealed that 3-CQA and 3, 5-CQA significantly increased the expression of lipid oxidation-related genes PPARα, CPT-1 and ACOX1 while 3-CQA, 3, 5-CQA and 3,4,5-CQA decreased the expression of lipogenic genes SREBP-1c, SREBP-2, HMGR, ACC, FAS. Overall, 3-CQA, 3, 5-CQA and 3, 4, 5-CQA may be the principal hypolipidemic components in PTF which can decrease intracellular lipid accumulation through up-regulating the expression of lipid oxidative genes and down-regulating the expression of lipogenic genes.
Carcinoma, Hepatocellular ; metabolism ; China ; Cholesterol ; metabolism ; Gene Expression Regulation ; Hep G2 Cells ; Humans ; Lipid Metabolism ; Liver Neoplasms ; metabolism ; Oleic Acid ; Pandanaceae ; chemistry ; Quinic Acid ; analogs & derivatives ; chemistry ; Sterol Regulatory Element Binding Protein 1 ; Triglycerides ; metabolism

The artificial 5-helix can inhibit the formation of trimer-of-hairpins structure during the course of HIV-directed membrane fusion and then inhibit human immunodeficiency virus (HIV) infecting target cells. But 5-helix was apt to form inclusion body when expressed directly in prokaryotic cell and was difficult to renature, which causes inconvenience to future study. We found a proper expression vector by simulating protein structure. We simulated its proper conformation in two vectors pGEX-6P-1 and pET44b by homology modeling. The contrast of conformations showed that the energy of salvation of its fusion protein with NusA in vector pET44b was higher than its fusion protein with glutathione-S-transferase (GST) in pGEX-6P-1 and its restriction site lay on the surface of its fusion protein in vector pET44b. 5-helix gene was amplified from pGEX-6P-1-5H by PCR, and was ligated to pET44b to construct recombinant vector pET44b-PSP-5Helix after tested correctly by enzymes digestion. The recombinant vector was transformed into Escherichia coli BL21 (DE3) to express 5-helix protein at different temperatures. Aim protein was purified with Ni column and GST column, and was determined by SDS-PAGE. Then the purified 5 -Helix was used to test the inhibitive activity of pseudo HIV virus infecting GHOST-CXCR4. Results show that its fusion protein with NusA can be effectively soluble expressed and easier to be cleaved, and that the purified 5-helix can efficiently inhibit pseudo HIV virus infecting GHOST-CXCR4 and its IC50 value is (22.77 +/- 5.64) nmol/L, which lay the foundation to further discuss the application in HIV-1 infection.
Carrier Proteins ; biosynthesis ; genetics ; Escherichia coli ; genetics ; metabolism ; Genetic Vectors ; genetics ; HIV Envelope Protein gp41 ; metabolism ; HIV-1 ; genetics ; Peptides ; genetics ; Repetitive Sequences, Nucleic Acid ; genetics ; Viral Fusion Proteins ; genetics ; Virus Internalization ; drug effects