Objective To observe the clinical effect of α1-antitrypsin gene therapy in the treatment of diabetes.Methods 81 cases with type 1 diabetes were randomly divided into conventional treatment group,islet stem cell transplantation group and gene therapy group,27 cases in each group.The conventional treatment group received the insulin therapy,the stem cell transplantation group received the islet cell transplantation,and the gene therapy group received stem cell therapy of α1-antitrypsin gene.The clinical effect of these three groups were observed.Results The insulin concentration of the gene therapy group was significantly higher than the islet stem cell transplantation group and the conventional treatment group at five time points(F =1 349.379,1 831.186,1 068.173,416.080,257.810,all P ＜0.05).The glucose concentration of the gene therapy group was significantly lower than the other two groups at six time points (F =1 212.243,586.057,962.495,582.887,650.015,1 181.808,all P ＜ 0.05).The degree of inflammatory cell infiltration in the gene therapy group was significantly lighter than in the islet stem cell transplantation group.Conclusion α1-antitrypsin gene therapy can significantly improve the therapeutic effect of diabetes,which is worthy of clinical application.

Objective To evaluate the safety,feasibility of primary closure after laparoscopic common bile duct exploration (LCBDE).Methods We retrospectively analyzed the clinical results of laparoscopic common bile duct exploration for common bile duct stones in 119 cases between July 2009 and August 2012.After all stones were removed,there were 63 cases with primary closure of the common bile duct (group A),and 56 cases with T tube drainage (group B).Results All operations were finished laparoscopically.There was significant difference in terms of operation time,postoperative hospital stay and fluid replacement between the two groups.There was no postoperative extrahepatic duct stenosis and biliary residual stones in the two groups.Conclusions Primary closure of common bile duct after LCBDE for common bile duct stones is safe,efficient and feasible.

The choice of the topic area and specific problem on which to conduct research is the mostimportant step in the research process.This paper focused on the development and execution of a clinical re-habilitation research study. The choice of the topic area. principle of research design. data collection and dataanalvsis of a research study have been discussed.

To evaluate the fatigue behavior of nitinol stents, we used the finite element method to simulate the manufacture processes of nitinol stents, including expanding, annealing, crimping, and releasing procedure in applications of the clinical treatments. Meanwhile, we also studied the effect of the crown area dimension of stent on strain distribution. We then applied a fatigue diagram to investigate the fatigue characteristics of nitinol stents. The results showed that the maximum strain of all three stent structures, which had different crown area dimensions under vessel loads, located at the transition area between the crown and the strut, but comparable deformation appeared at the inner side of the crown area center. The cause, of these results was that the difference of the area moment of inertia determined by the crown dimension induced the difference of strain distribution in stent structure. Moreover, it can be drawn from the fatigue diagrams that the fatigue performance got the best result when the crown area dimension equaled to the intermediate value. The above results proved that the fatigue property of nitinol stent had a close relationship with the dimension of stent crown area, but there was no positive correlation.
Alloys ; Computer Simulation ; Equipment Failure Analysis ; Finite Element Analysis ; Stents

Objective:To study the the correlation between the diameter or angle of thoracic-lumber pedicle and vertebral number.Method:X-ray and CT scan were performed on 46 male spine specimens.The length of pediele screw path,the cress-section angle(e) and the sagittal angle(f) of the pedicle,the width of the inner diameter of the pediele and the distance between the two pedicles were measured.The ordinal number of T1-L5 vertebral segment was numbered by 1-17.SPSS 11.5 software was used for statistical analysis.Result:The data showed a positive linear correlation with the vertebral numbers including length of T1-L4 pedicle screw path (R2=0.716),T8-L5 pedicle width (R2=0.673),T4-L5 pedicle distances (R2=0.771),T1-T2 f-angle (R2=0.767) ,T2-T4 f-angle (R2=0.908),T12-L5 pediele e-angle (R2=0.710).The negative linear correlation with thevertebral numbers included T2-T3 pedicle width(R2=0.792),T1-T4 pedicle distances(R2=0.866),T7-L5 f-an-gle(R2=0.931),T1-T6 pedicle e-angle (R2=0.774).However,the T1-T2 and T4-T7 pediele width,the T4-T6 pediele f-angle,as well as the T6-T12 pedicle e-angle had no significant correlation with the vertebral num-bers.Conclusion:Apart from the T1-T2 and T4-T7 pedicle width,the T4-T6 pedicle f-angle and the T6-T12 pedicle e-angle,the diameter or angle of the thoracic-lumbar pedicle have correlation with the vertebral numbers with meaningful linear regression equation.

BACKGROUND: Revascularization is necessary for tissue-engineered bone implantation by osteogenesis to effectively repair bone defect.OBJECTIVE: To evaluate marrow mesenchymal stem cells (MSCs) modified by bone morphogenetic protein 2 (BMP-2) in combination with polylactic acid/polycaprolactone (PLA/PCL) to repair rabbit radial bone defect during the vascularization, and to investigate the promotive effects of BMP-2 gene on the vascularization of bone graft.DESIGN: Randomized controlled animal study.SETTING: This study was performed in the Central Laboratory of China Medical University from January to December 2005.MATERIALS: PLA/PCL with 150-250 μm pore diameter and 90% interval porosity was provided by Changchun Applied Chemistry Institute, Chinese Academy of Science. Sixty 3-month-old New Zealand rabbits were selected in this study.METHODS: Sixty rabbits were randomly divided into four groups with 15 rabbits in each group. Subsequently, middle segments of bilateral radial bone were obtained to establish 1.5-cm bone defect models that were implanted with processed artificial bones. Adenovirus carrying BMP-2 (AD-BMP-2) group: Artificial bones were processed with transfected BMP-2 cells plus PLA/PCL; Control group: Artificial bones were processed with adenovirus carrying β-gal gene (Ad-Lacz) plus PLA/PCL; Non-transfection group: Artificial bones were processed with non-transfected cells plus PLA/PCL; PLA/PCL group: PLA/PCL alone for transplantation.MAIN OUTCOME MEASURES: Four, eight, and twelve weeks after surgery, X-ray was used to observe new bone formation; stereoscopic microscope to observe distribution of microvessels; haematoxylin-eosin staining to detect the relationship between microvessels and bone formation; transmission electron microscope to investigate the correlation between osteoblasts and vascular endothelial cells, detect vascular endothelial growth factor expression, and calculate the number of microvessels.RESULTS: Four postoperative weeks in the AD-BMP-2 group, numerous microvessels were observed; stent pore was full of cartilage calluses; active osteoblasts grew around microvessels; vascular endothelial growth factor expression and numbers of microvessels were higher and more than those in other groups. Eight postoperative weeks, osteoblasts gradually increased in the bone graft; microvessels circuitously expanded and connected each other; cartilage callus changed into trabecular bone. Twelve postoperative weeks, cortical bones were successive; medullary cavity recanalized; microvessels longitudinally arranged in order. Ability of bone formation in the control group and non-transfection group was weak, and vascular regeneration was slow; 12 postoperative weeks, bone defect was primarily repaired; microvessels were distributed along the pores of newborn bone trabecula. Newborn vessels were hard found in the PLA/PCL group at each time point. Twelve postoperative weeks, bone extremities sclerotized, and defect regions were fully filled by fiber tissues.CONCLUSION: Transfected BMP-2 gone by up-regulating vascular endothelial growth factor expression can indirectly induce vascularization of bone graft, promote survival of seed cells, and accelerate bone formation.

BACKGROUND: Tissue engineered bone constructed in vitro is a compound of cell and material; additionally, revascularization plays a key role in effectively repairing bone defect after transplantation of tissue engineered bone.OBJECTIVE: To evaluate the influence of antigen-extracted bovine cancellous bone stent combining with bone morphogenetic protein 2 (BMP-2) on vascularized reaction during reparative process of bone defect.DESIGN, TIME AND SETTING: Randomized grouping design and controlled animal study, which was performed at the Central Laboratory, China-Japan Friendship Hospital Affiliated to Jilin University.MATERIALS: Sixty rabbits of clean grade were selected in this study. Superior cancellous bone of bovine humerus was used to establish bovine cancellous bone stent. Recombinant adenovirus carrying human BMP-2 (Ad-BMP-2) and β -galactosidae gene (Ad-Lacz), and recombinant human BMP-2 (rhBMP-2) were graciously presented by Dr. Oliver and Pro. Gao, Department of Pathology of Jilin University.METHODS: Marrow mesenchymal stem cells were extracted from 60 rabbits, and then they were transfected with BMP-2 adenovirus vector to repair 1.5-cm defects of radial bone of both upper extremities by combining with bovine cancellous bone transplantation. Rabbits were randomly divided into 5 group with 12 in each group: Ad-BMP-2 transfected cells+bovine cancellous bone group, non-transfected cells+rh-BMP-2+bovine cancellous bone group, Ad-Lacz transfected cells +bovine cancellous bone group, non-transfected cells + bovine cancellous bone group, and bovine cancellous bone group. Transplanted bone was fixed by tightly suturing tunica muscularis and anadesma.MAIN OUTCOME MEASURES: New bone formation was observed by X ray at 4, 8, and 12 weeks after surgery; microvascular ink perfusion was used to observe vascular distribution; transmission electron microscope was used to observe osteoblasts and vascularization; hematoxylin-eosin (HE) staining, alcian blue staining, and VonKossa staining were used to observe correlation between microvessels and bone formation; immunohistochemical staining of vascular endothelial growth factor was used to detect gray value; immunohistochemical staining of CD34 was used to specifically label vascular endothelial cells for microvascular amount.RESULTS: Sixty rabbits were included into the final analysis. X-ray and immunohistochemical examinations demonstrated that bone formation and vascularization in the Ad-BMP-2 transfected cells+bovine cancellous bone group and non-transfected cells+rh-BMP-2+bovine cancellous bone group were superior to those in other three groups. After four weeks, microvascular ink perfusion indicated that a branch of small vessels was formed in pore of trabecular bone. Vascular density was higher in the peripheral domains but lower in the central regions. Transmission electron microscope suggested that a lot of osteoblasts and new vascular buds with active function were observed four weeks after surgery. Mature lamellar bone was formed 12 weeks after surgery, and structure of new vessels was complete. Detection of vascular endothelial growth factor expression and microvascular amount indicated that content of vascular endothelial growth factor in the Ad-BMP-2 transfected cells+bovine cancellous bone group was significantly higher than that in other four groups (P<0.01), and microvascular amount was also significantly higher than that in other four groups (P<0.01).CONCLUSION: BMP-2 gene can indirectly induce vascularization of transplanted bone through up-regulating vascular endothelial growth factor expression, which is superior to rh-BMP-2.

BACKGROUND:The incorporating of zeolites or porous fillers into polymer membranes can improve the pervaporation separation properties of membranes.But the effect mechanism of zeolites or porous fillers on membrane properties needs to be further studied.OBJECTIVE:The study was designed to prepare ZSM-5 zeolite incorporated chitosan membrane by solution blending method to investigate the effecIs of zeolite on membrane pervaporation properties.DESIGN:A controlled observation.SETTING:Dalian Institute of Chemical Physics,Chinese Academy of Sciences.MATERIALS:This study was performed at the Laboratory of New Type Membrane Separation Technology,Dalian Institute of Chemical Physics,Chinese Academy of Sciences in May 2006.Chitosan,with deacetylation degree of 75%-85%,was obtained from Sigma-Aldrich Chemical Company,USA;Dimethyl carbonate(DMC),with purity of 99%,was purchased from Fluka Chemical Company,USA:ZSM-5 zeolite was kindly supplied by Dalian Institute of Chemical Physics,Chinese Academy of Sciences,China;Methanol,with purity＞99.5%,were purchased from Shenyang Lianbang Chemical Company,China.METHODS:ZSM-5 zeolite incorporated chitosan membranes were prepared by solution blending method.properties.RESULTS:Scanning electron mieroscope demonstrated that zeolite was uniformly distributed in the membrane matrix and the membranes were free from possible defects.The separation selectivity of dimethyl carbonate(DMC)/methanol mixtures was dominated by solubility selectivity rathcr than diffusivity selectivity.Swelling degree increased and the permeation flux of the membranes increased significantly with the zeolite content increasing.From the temperature-dependent permcation values,the Arrhenius activation parameten were estimated.CONCLUSION:The pervaporation results indicated that the membranes incorporated with the ZSM-5 zeolite exhibited better separation properties for DMC/methanol mixtures comparing with homogeneous chitosan membranes.

This paper analyzed the current status of clinical research at Peking University, which was compared with that of a number of international and domestic universities. Suggestions were put forward in accordance with the current domestic problems in clinical research.