ABSTRACT
Objective To study the effect and mechanism of down-regulating Silt2/Robo 1 signaling pathway on rabbit iliac artery after angioplasty restenosis. Methods The 30 male New Zealand white rabbits were divided randomly into 3 groups , namely the blank group , the control group , and the experimental group , 10 rabbits in each group. Hign-fat feeding , the rabbits were produced endothelial denudation of iliac artery stenosis model. Another 4 weeks of feeding , percutaneous balloon angioplasty was performed. Then R5 antibody was injected into the abdominal cavity. After 4 weeks of feeding ,angiography again. The results of angiography was analysied by image workstation. The concentrations of Slit2 and Robo1 was detected by ELISA. The iliac artery tissue examined by HE staining. Results The rabbit iliac artery after angioplasty restenosis animal model was set up successfully. Compared with the control group and the experimental group , the serum concentration of Slit2 and Robo1 were significantly higher (P < 0.01) than the blank group. But in the experimental group, the Slit2 and Robo1 serum concentrations were significantly lower than those in the control group (P < 0.05) after R5 antibody intervention. The area ratio stenosis and diameter stenosis rate of iliac artery were reduced that confirmed by angiography. Conclusion The expression of Slit2/Robo1 was significantly higher in the rabbit model of vascular restenosis. R5 antibody can effectively inhibit the expression of Slit2/Robo1. Down regulation of Slit2/Robo1 signaling pathway in the treatment of restenosis after angioplasty in rabbits.
ABSTRACT
<p><b>OBJECTIVE</b>To assess the feasibility and safety of using the modified active fixation pacing leads model to pace the right ventricular outflow tract septum.</p><p><b>METHODS</b>A total of 136 patients undergoing artificial heart pacemaker implantation with active fixation pacing leads were randomized into two groups to receive conventional right ventricular outflow tract pacing (CRVOTP) or modified right ventricular outflow tract pacing (MRVOTP). The electrode lead wire core was modeled in a double-curved three-dimensional shape in CRVOTP group and in a J-shaped bend in MRVOTP group before fixation at the right ventricular outflow tract septum.</p><p><b>RESULTS</b>Right ventricular outflow tract septum pacing was achieved successfully in all the patients. None of patients experienced serious complications. No significant differences were found between the two groups in the number of times of electrode fixation, pacing thresholds, impedance, R wave height or QRS wave width during the operation, but MRVOTP was associated with a reduced time of X -ray exposure and operation (P<0.05) due to the convenience in electrode modeling and in passing the leads through the tricuspid annulus and the direct access to the right ventricular outflow tract septum. Postoperative follow-up of the patients showed no incidence of active fixation pacing lead dislocation and comparable pacing thresholds of the ventricular electrodes, impedance, R wave height and QRS wave width between the two groups.</p><p><b>CONCLUTIONS</b>Using the modified active fixation pacing leads model to pace the right ventricular outflow tract septum can reduce the time of X -ray exposure and operation with a low probability of lead damage.</p>