RNAi沉默dUTPase对SW620细胞黏附的影响

The effect of inhibition of dUTPase expression by RNAi on adhesive ability of SW620 cell

目的采用RNAi沉默dUTPase的表达,观察SW620细胞黏性的改变。方法合成两条编码发夹siRNA序列的单链DNA,并将其克隆到pSilenCircle载体中,构建重组质粒sidUTPase/pSilenCircle和无关基因的重组质粒siFly/pSilenCircle。以上述重组质粒分别转染SW620细胞,RT-PCR和Westernblot检测dUTPase的表达,异质黏附实验分析细胞黏附性的改变。结果成功地构建了2个dUTPase发夹siRNA的真核表达载体sidUTPase/pSilenCircle和无关基因重组质粒siFly/pSilenCircle。与siFly/pSilen-Circle转染组比较,sidUTPase/pSilenCircle转染组SW620细胞dUTPase的表达明显下调,细胞异质黏附能力减弱。结论构建的dUTPase发夹siRNA的真核表达载体sidUTPase/pSilenCircle可有效抑制SW620细胞的dUTPase表达,降低细胞的异质黏附性。

Objective To evaluate the curative effect of valsartan associated with low-dose amiodarone on the recurrence of atrial fibrillation （AF）, the left atrial diameter （LAD）, P wave dispersion （Pd） and the maximum P wave duration （Pmax） in patients with paroxysmal AF. Methods 76 patients with paroxysmal atrial fibrillation （PAF） were randomized to valsartan （test group） and placebo （placebo group）, both associated with low-dose amiodarone, and were followed up for 18 months. The patients were asked to report any episode of symptomatic atrial fibrillation and to perform an ECG as early as possible. AF load, Pmax, Pd and LAD were measured before and at the 6th, 12th, and 18th month after the treatment. Results At least one ECG-documented episode of AF was reported in 16% of the patients in test group and in 41% in placebo group, the difference was significant （P〈0. 01）. No significant difference of AF load existed in the two groups before and at the 6th month after the treatment, and the AF load in test group was significantly lower compared with that in placebo group at the 12th （48. 6±22. 5min/24h vs 37. 4±18. 6min/24h, P〈0. 05）, and 18th month （76. 4±35. 8min/24h vs 52. 6±22. 5, P〈0. 01） after the treatment. The Pmax and Pd showed no significant difference between the two groups before treatment, while the Pmax was higher in placebo group at the 6th, 12th, and 18th month after the treatment than that in test group, and Pd was also higher in placebo group at the 6th, 12th, and 18th month after the treatment than that in test group. There was no significant difference of LAD between the two groups before and at the 6th month after the treatment, and the LAD in placebo group was significantly enlarged compared with that in placebo group at the 12th （36.1±1.61mm vs 34.9±1.71mm, P〈0. 05）, and 18th month （37.0±1.49mm vs 35.3±1.45mm, P〈0. 05） after the treatment. Conclusion The use of valsartan in combination with amiodarone is more effective than amioda- rone alone in reducing the recurrence of AF in patients with paroxysmal AF, and this might be related to possible favorable impact of angiotensin H receptor blockers （ARB） on the atrial structural remodeling in this type of patients.