BACKGROUND:Restenosis easily occurs after stent implantation,thus it is worthy optimizing the stent design and evaluating its structural safety.OBJECTIVE:To simulate the deformation of balloon-expandable stainless steel stents by the finite element method,and calculated the radial displacements and stresses after expansion in different designs.DESIGN:A comparative calculated analysis.SETTING:Laboratory of Laser Processing Technology,South China Normal University.MATERIALS:The experiment was carried out in the Laboratory of Laser Processing Technology,South China Normal University in October,2006.The model of slotted-tube stent was used.METHODS:The simulations were carried out to expand a stainless steel stent with 2 mm in outer diameter,10 mm in length and 0.09 mm in strut width.Due to the symmetry of the stent by utilizing the correct boundary conditions,a half model was used to simulate the deformation process.①In stent I,the slot length was 2.0,4.0 and 4.0 mm for a,b and c respectively.In stent Ⅱ,the slot length was 1.5,4.5 and 4.0 mm for a,b and c respectively.In stent Ⅲ,the slot length was 1.8,4.2 and 4.0 mm for a,b and c respectively.Three points(A,B and C)in vary strut were selected to study the displacement during the process of deformation.The pressure applied as a surface load on the inner stent surface was 0.5 Mpa.②The dimensions and radial displacements of the three stent designs in the process of expansion were calculated,and the changes of deformation stresses were observed in the third design.MAIN OUTCOME MEASURES:① The dimensions and radial displacements of the three stent designs in the process of expansion were calculated;②The changes of deformation stresses were observed in the third design.RESULTS:The shape of the expended stent I looked like a dumbbell.The maximum radial displacement of point C obtained is found to be 2.1 mm,and the point B obtained the smallest radial displacement of 0.3 mm in the three defined points.In stent Ⅱ,the maximum radial displacement obtained is found to be point B of 2.1 mm,and the point C obtained the smallest radial displacement of 1.20 mm in lhe three defined point,which obtained a spindly shaped stents.In stent Ⅲ,the maximum radial displacement obtained is found to be point B of 2.2 mm,and the point A obtained the smallest radial displacement of 1.85 mm in the three labeled point,which produce more uniform expansion than the last two stent designs.②In stent Ⅲ,the stresses and the radial displacements achieved as the pressure increased gradually.CONCLUSION:The stress concentrations and the uniformity of the expanded stent can be decreased through optimizing the stent design by finite element method,which can be used in optimizing the stent design and evaluating the structural safety of stents.

Objective To evaluate the efficacy of inspiring carbogen and low concentration oxygen combined with late coupe accelerated hyperfraction radiotherapy on esophageal carcinoma.Methods 74 patients with esophageal carcinoma were randomly divided into two groups:the trial group and the centrol group,which consisted of 37 patients respectively.6MV X-ray was employed in the two groups.The schedule of the trial group was as following:conventional radiotherapy of 1.8～2.0Gy per day was employed during the first phase to a total dose of 38～40Gy,followed by late course accelerated hyperfraetion radiotherapy(twice fractions per day,interval between two fractions more than 6 hours,1.3～1.4Gy per fraction,middle total dose of 64.2Gy).Carbogen and low concentraetion oxygen was inspired during the course of radiation.Results 71 patients were enrolled.At the end of radiation at a total dose of 38～40Gy,complete remission rate(CRR)in the trial group was 31%,whereas that in the control group was 19%(P＞0.05),when the whole radiotherapy was finished,the CRR was 57%and 31%(P＜0.05)respectively,and one month after radiotherapy.the CRR was 71%and 33%respectively(P＜0.01).Six months after radiotherapy,the CRR WaLa 74%and 36%respectively(P＜0.01).Thelocal controlrate of sixmonthswas 91% and 72% respectively in the two groups(P＜0.05).Conclusions Inspiring carbogen and low concentration oxygen combined with late course accelerated hyperfraction radiotherapy may sigllificantly improve short-term efficacy and local control rate in esophageal carcinoma patients in Ⅰ～Ⅲstage.Furthermore,its side effects can be tolerated,and its elongating life time of patients may be prognostic.

Objective To observe the effects of cyclovirobuxinum D(Cvb-D)on the myocardium cell apoptosis of myocardial ischemia rats.Methods The rats were given Cvb-D 0.55,1.1 and 2.2 mg/kg orally per day for 21 days respectively.The myocardial ischemia model was induced by isoprenaline intraperitoneal injection.Myocardium tissue was observed under light microscope and end labelling TUNEL method was used to determine the cell apoptosis.Then the average percentage of apoptosis cell was figured out to evaluate the effect of Cyb-D.Results Cvb-D obviously lightened isoprenaline-induced myocardial pathological changes such as turbulence of myocardial fiber,plasmolysis of necrotic cell,inflammatory cell infiltration of necrotic interstitial region.Cvb-D remarkably inhibited myocardium cell apoptosis of myocardial ischemia rats caused by isoprenaline.Conclusion Cvb-D has the action of ameliorating myocardium cell apoptosis caused by myocardial ischemia.

Objective To explore the effect of hepatectomy or cholangiolithotomy on patients with hepatocholangic stones. Methods The clinical data of surgical treatment of 316 patients with hepatocholangic stones combined with bile duct stricture was retrospectively analyzed. The patients were divided into two groups:172 patients chiefly underwent hepatectomy,and the other 144 patients chiefly underwent cholangiolithotomy. Results The ratio of residual stones and reoperation in the hepatectomy group was significantly lower than those in the cholangiolithotomy group (P

AIM: To study the effects of Zhongjingweiling Capsule (Fructus Amomi, Cortex Cinnamemi, Rhizoma Alpiniae Galangae, Fructus Foeniculi, Radix Glycyrrhizae, etc.) on analgesia, anti inflammation and gastrointestinal peristalsis inhibition. METHODS: The effect of analgesia was tested by the method of writhes and hot plate on mice. The effect of anti inflammation was tested by injecting acetic acid and implanting cotton pellet and xylene into mice. RESULT: Zhongjingweiling Capsule effectively inhibited the swelling of mouse pinna induced by xylene and the increase of peritoneal capillary permeability caused by the acetic acid injected into mice. The capsule also decreased the proliferation of granuloma caused by implantation cotton pellet significantly and had an abirritant effect on the algesia induced by acetic acid and hot plate. Besides, it effectively inhibited the gastrointestinal peristalsis. CONCLUSION: Zhongjingweiling Capsule is an effective medicine in anti inflammation, analgesia, and gastrointestinal peristalsis inhibition.

Objective To assess the effect of hybrid debranching technique in treatment of patients with traumatic aortic arch rupture combined with pseudoaneurysm.Methods Clinical data of 3 patients with traumatic aortic arch rupture combined with pseudoaneurysm repaired using debranching technique from June 2011 to June 2013 were analyzed to determine their clinical features and treatment options.Hypersound or computed tomography angiography (CTA) was performed to confirm the therapeutic effects at postoperative 1 week,3,6,and 12 months as well as annually thereafter.Results All patients underwent operation uneventfully.Operation time was 6.8-10.5 hours (mean,7.6 hours) and intraoperative blood loss was 250-450 ml (mean,310 ml).Length of stay was 26-45 days (mean,32 days).There were no deaths at the 0.5-2 years of follow-up.Hypersound or CTA revealed no leakage of contrast medium after operation.Conclusion Hybrid debranching technique greatly reduces surgical trauma and provides satisfactory outcome and good function recovery.

Objective To study the local anatomic structure of subclavian vein and have a good command of operating methods and skills on subclavian vein catheterization (SVC) so as to improve the success rate of puncture. Methods Retrospectively analyze the clinical data of 600 cases of hospitalized patients who have had SVC (male 410, female 190) in our hospital from March 2010 to March 2014. Results There were 582 cases (97%) of successful puncture,including 546 cases (91%) of one-time puncture success,38 cases (6. 3%) of repeated puncture or other types of puncture,and 16 cases (2. 7%) of failed puncture. Postoperative complications occurred in 22 patients (3. 7%),including 8 cases (1. 3%) of strayed into the artery,3 cases (0. 5%) of pneumothorax,5 cases (0. 8%) of catheter tip into the internal jugular vein,2 cases (0. 3%) of catheter related infection,2 cases (0. 3%) of catheter blockage,and 2 cases (0. 3%) of arrhythmia. Conclusion SVC is easy,safe and reliable,and it is of high success rate and less complications. Catheter retention time of SVC is longer. From the above,SVC is a good central venous puncture method which is worth of popularizing in clinical use.

AIM:To construct recombinant adenovirus vector carrying human miR-133a and study its expression in human mesenchymal stem cells(hMSCs).METHODS:The PCR product containing miR-133a was amplified from human genomic DNA and inserted into the adenoviral shuttle vector pAdTrack-CMV.Then the recombinant shuttle plasmid linearized by pmeⅠwas cotransformed into competent E.coli.BJ5183 with the adenoviral backbone plasmid pAdEasy-1 to generate the recombinant adenovirus vector rAd-mir-133a.rAd-mir-133a was then packaged and amplified in human embryonic kidney 293(HEK293) cells.The purified rAd-miR-133a was used to infect the hMSCs and the expression of miR-133a was detected by non-quantitative RT-PCR and real-time PCR.RESULTS:The recombinant adenovirus shuttle vector pAdTrack-CMV-miR-133a was constructed and verified by restriction endonuclease analysis and DNA sequence analysis.rAd-miR-133a was successfully packaged and amplified in HEK293 cells.The transcriptions of primary miR-133a and mature miR-133a were over-expressed in the hMSCs infected with rAd-miR-133a.CONCLUSION:The recombinant adenovirus vector carrying human miR-133a is successfully constructed,which lay a foundation for miR-133a function study.

As an important medical instrument in percutaneous transluminal coronary angioplasty, endovascular stents must have excellent biocompatibility. In this paper, after a description of the performance and fabrication process of stents, we analyzed the technology to improve the biocompatibility of stents during the fabrication process which is the effective method for decreasing the rate of restenosis.
Angioplasty, Balloon, Coronary ; Animals ; Coronary Disease ; therapy ; Coronary Restenosis ; prevention & control ; Humans ; Stents