Preparation of valved aortic stent and trans-catheter implantation to ascending aorta in vivo / 第二军医大学学报

Objective: To develop valved aortic stent and to assess the feasibility of its trans-catheter implantation to the ascending aorta in vivo. Methods: We designed self-expandable nitinol stents (15-19 mm in diameter) according to the internal diameter of the ascending aorta of Chinese miniswines. Bovine pericardium was cross-linked with 0.6% glutaraldehyde solution for 36 hours, and then was shaped and sutured into the stents. Fluid passing test, pre-releasing test and static test of pressure in the tube were performed in all devices. The devices were tried to be inserted percutaneously through common iliac artery to deploy in the ascending aorta in 7 Chinese miniswines. Results: In vitro test showed that the closure of the percutaneous valved aortic stent leaflets was satisfactory, and the fluid flow was not restricted in the opposite direction. The devices could be released through the catheter, expanded completely, and be fixed rapidly in the tube. The devices were deployed using 12F-16F catheter and were inserted through common iliac artery in 6 of the 7 Chinese miniswines. All devices were implanted in the desired position, with 6 expanded completely and fixed rapidly in the ascending aorta. One did not expand completely and was displaced. Animals were executed and dissected after 24 hours. All the devices were fixed in the ascending aorta and there were no thrombus. Conclusion: The function of the percutaneous valved aortic stent is satisfactory. The size of compressed device is suitable for catheterization. It can be successfully implanted into the ascending aorta by using a retrograde method through common iliac artery.

Effect of the valved stent on closure of patent ductus arteriosus in a miniswine model / 中华心血管病杂志

<p><b>OBJECTIVE</b>To evaluate the feasibility of a valved stent on closure patent ductus arteriosus in a Chinese miniswine model.</p><p><b>METHODS</b>Self-expandable nitinol stents were made of Ni-Ti shape memory alloy (9 mm in diameter). Bovine pericardium was shaped and sutured onto the stents. Fluid passing test, pre-releasing test and static test of pressure in tube were performed in all devices before use. In eight Chinese miniswine, vascular grafts (PTFE vascular prosthesis) were surgically inserted between the descending thoracic aorta and pulmonary artery for establishment of patent ductus arteriosus model. Valved stents were deployed to occlude the patent ductus arteriosus. Echocardiography was performed two hours post operation. Aortic angiography was made 30 days post operation in survived animals. Animals were then sacrificed for autopsy and electron microscopy examinations.</p><p><b>RESULTS</b>In vitro testing showed that the closure of the valved stent leaflets was satisfactory and fluid flows were not restricted in the opposite direction. The valved stents could be released through catheter, expanded completely, rapidly fixed in the tube. Closure of patent ductus arteriosus was succeeded in 6 out of 8 animals. One animal died of respiratory failure 2 hours post operation, another one died of pulmonary embolism due to valved stent displacement. Resident shunt was not evidenced by echocardiography, aortic angiography and dissection examinations in the remaining 6 animals. The new endothelial tissue fully covered the pulmonary and aortic sides of patent ductus arteriosus in 4 and 3 animals respectively. The electron microscopic observation revealed endothelial coverage of dives.</p><p><b>CONCLUSION</b>The valved stent could effectively close artificial patent ductus arteriosus in vivo with satisfactory new intima covering on both sides of patent ductus arteriosus.</p>

Combined use of transmyocardial stents with gene therapy in the treatment of acute myocardial infarction / 中华心血管病杂志

<p><b>OBJECTIVES</b>To determine the efficacy of combined use of transmyocardial stent with gene therapy to treat acute myocardial infarction in porcine model.</p><p><b>METHODS</b>24 Chinese mini swines have been divided into 4 groups randomly: group myocardial infarction (group MI n(1) = 6), group transmyocardial stent (group ST n(2) = 6), group vascular endothelial growth factor (group VEGF n(3) = 6), group transmyocardial stent and VEGF (group ST + VEGF n(4) = 6). In group MI, acute myocardial infarction animal model has been established by the ligation of the left descending coronary artery. In group ST, after the establishment of the model, 3 transmyocardial stents were implanted. In group VEGF, an expression plasmid containing the gene-encoding VEGF(165) (300 microg) was administered directly in the myocardium at 6 sites. In group ST + VEGF, both transmyocardial stents and expression plasmid containing the gene-encoding VEGF(165) are applied. 4 weeks later, the animals are sacrificed and echocardiography and pathological analysis have been done.</p><p><b>RESULTS</b>The density of blood vessel in group ST, VEGF and ST + VEGF are significantly higher than group MI. And capillary density in group ST + VEGF is the highest in these groups statistically. Expression of VEGF was detected in group ST, VEGF and ST + VEGF, but in group VEGF and ST + VEGF the level of expression are higher.</p><p><b>CONCLUSION</b>Combined use of transmyocardial stent with gene therapy has synthetic effect for the treatment of acute myocardial ischemia in porcine model and can significantly increase the vascular density.</p>

Changes of serum cytokeratin 19 fragment in postoperative patients with non-small cell lung cancer / 中华全科医师杂志

Objective To study the clinical value of serum cytokeratin 19 fragment (CYFRA21-1) as a biomarker in evaluating its prognosis,monitoring and follow-up of the postoperative patients with non- small cell lung cancer (NSCLC).Methods Serum CYFRA21-1 was determined by radioimmunoassay for 207 patients with NSCLC before and after surgical operation at Tongji Hospital,Shanghai.Relationship between serum CYFRA21-1 and the prognosis,recurrence and metastasis of lung cancer was analyzed retrospectively.Results The patients were followed-up for 37 months in average.Preoperative serum CYFRA21-1 was positive in 42.0% (87/207) of all the cases,48.8% (60/123) of squamous cell earcinama and 34.6% (27/78) of adenocarcinoma,with statistical significance (X~2=3.901,P