Objective: To investigate the efficiency and feasibility of DNA plasmid transfected into retinoblastoma (RB) cells by microbubbles of different dosage and ultrasound with various intensity, and to afford a base for effective and directional gene delivery. Methods: In order to prevent the harm to RB cells, the optimum ultrasound intensity and microbubbles dosage were screened. The cultured retinoblastoma cells were exposed to different ultrasound with intensity of 0.25, 0.5, 0.75, 1.0 and 1.25 W/cm2 respectively, and the time were all 60 s. The other RB cells were exposed to microbubbles of various dosage of 1%, 10%, 20% and 30% respectively. According to the optimum ultrasound intensity and microbubbles dosage, EGFP gene were transfected into RB cells. After 24 to 48 hours, the EGFP expression in the RB cells were detected by fluorescence microscopy and RT-PCR. Results: Ultrasound with the intensity under 0.75 W/cm2 (60 s), and microbubbles with the dosage under 20%, did no harm to RB cells. The transfected efficiency of the two groups (0.5 W/cm2 and 0.75 W/cm2) were both higher than other groups. Conclusion: The efficiency of DNA vector transfected into RB cells could be increased obviously by optimum ultrasound intensity and microbubbles dosage.

Objective To investigate whether ultrasound-mediated microbubble destruction could effectively deliver plasmid to retinoblastoma cells.Methods The cultured retinoblastoma cells were divided into six groups.The first group was exposed to ultrasound and the second group was given proper dose of microbubbles.We added this plasmid to the third group and plasmid with microbubbles to the forth group.Plasmid,microbubbles and ultrasound were applied to the fifth group and plasmid with liposome to the sixth group.After 24 to 48 hours,the EGFP expression in the retinoblastoma(RB) cells were detected by fluorescence microscopy and RT-PCR.Trypanblue staining were adopted to measure the cell vitality of the first and second group.Results The infection efficiency of the fifth group were similar to that of the sixth group,and were both higher than other groups.Ultrasound used in the experiment did not harm to the cells neither did the microbubbles.Conclusions The EGFP expression in RB cells were increased with the administration of ultrasound-mediated microbubbles destruction.

Objective:To evaluate the feasibility of argon laser-induced choroidal neovascularization(CNV)model in the pigmental rabbits in order to establish the foundation for studying the mechanism of CNV and for the development of treatment for CNV.Methods:Experimental eyes in 20 rabbits were received a series of 20 argon green laser(514.5nm) lesions per eye (700 mW,50um,0.1s).Fundus fluorescein angiography(FFA) and indocyanine green angiography (ICGA) were performed,then the rabbits were sacrificed immediately,the eyes were enucleated and processed for histopathologic and immunohistochemistry examination on days 3,7,14,21,30.Results:CNV first appeared on day 7 after photocoagulation,reaching the peak on day 21.The incidence of CNV was 63.0%.Disciform leakage staining appeared in the FFA.ICGA showed that the disciform area was filled with CNV.CNV was ascertained by light microscopy.The immunohistochemistry examination of VEGF was positive in ganglion cell layer and inner nuclear layer of retina from 2w after photocoagulation.Conclusion:The present studies demonstrated that argon laser photocoagulation could be used to produce choroidal neovascularization experimental model in the pigmental rabbits.CNV can be induced rapidly by the method,persists for a long period and at a high successful rate.VEGF plays a role in the formation of CNV.

糖尿病性视网膜病变、年龄相关性黄斑变性、中心性渗出性脉络膜视网膜病变等许多眼部疾病的共同特征是视网膜或视网膜下新生血管。色素上皮衍生因子(PEDF)是近年来发现的能有效抑制新生血管形成的因子，与血管内皮生长因子(VEGF)等一起控制了新生血管的发生过程。PEDF有抑制新生血管、营养神经、诱导肿瘤细胞凋亡等作用。本文主要综述其上调下调规律、其作用的研究现况及应用前景。

Objective To evaluate the effect of Celecoxib,a selective cycloxygenase-2(COX-2) inhibitor,inhibits retinal vascular endothelial growth factor(VEGF),COX-2 expression and vascular leakage with argon laser-induced choroidal neovascularization(CNV) model in the pigmental rabbits.Methods 20 healthy colored rabbits were divided into 4 groups: laser group,Celecoxib group,indomethacin group and control group.Each group has 5 rabbits(10 eyes).Celecoxib was administered B.i.d.by oral gavage(50 mg/kg) and indomethacin by oral also(25 mg/d).Experimental eyes in 15 rabbits were received a series of 20 argon green laser(647 nm) lesions per eye(0.7 W,50 μm,0.1 s).Fundus fluorescein angiography(FFA) and indocyanine green angiography(ICGA) were performed,then the rabbits were terminated immediately.The eyes were enucleated and processed for histopathologic and immunohistochemistry examination on the 3rd day,7th day,14th day,21st day,30th day.Results CNV was firstly appeared on day 7 after photocoagulation,reaching the peak on the 21st day.The incidence of CNV was 63.0%.Disciform leakage staining appeared in the FFA.The immunohistochemistry examination of VEGF and COX-2 were positive in retina from the 2nd week after photocoagulation,and they had the same change trend.Conclusion The present studies demonstrated that celecoxib cannot block CNV induced by laser photocoagulation but it can reduce the express of VEGF and incidence of CNV.