Purpose:To investigate the effect of small interfering RNA (siRNA)targeting VEGF of retinal pigment epithelium (RPE) cells on the growth activity of human retinal vascular endothelial cells (RECs) under a co-culture s...Purpose:To investigate the effect of small interfering RNA (siRNA)targeting VEGF of retinal pigment epithelium (RPE) cells on the growth activity of human retinal vascular endothelial cells (RECs) under a co-culture system.Methods:By applying the vector.(pGPU6)-based siRNA plasmid gene silence system,we specifically silenced VEGF expression of RPE cells (ARPE-19) through plasmid (pG-PU6-VEGFA-siRNA)transfection.Reverse transcription polymerase chain reaction(RT-PCR) was applied for selecting the most efficient siRNA segment among three pGPU6-VEGF-siRNA groups (siRNA-1,siRNA-2 and siRNA-3).Treated RPE cells were co-cultured with RECs in a co-culture system made up of a 24-well culture plate and transwell inserts assembled inside During 7-day culture period,the growth ca-pacity of RECs were observed and tested in the form of cell counting assay.Three groups were established in this study:RPE cells transfected with pGPU6-VEGF-siRNA and co-cultured with RECs (group A),RPE cells transfected with siR-NA null vector and co-cultured with RECs (group B),and RECs cultured alone (group C).Results:After transfection,VEGF expression levels of RPE cells in three pGPU6-VEGF-siRNA groups (siRNA-1,siR-NA-2 and siRNA-3)evaluated by RT-PCR were 2.56 ±0.45,1.17 ±0.38 and 4.39 ±0.51,respectively (n =10).siRNA-2 was selected as the foremost segment for transfection (P < 0.05,SNK-q test).During the 7-day co-culture period,the influence upon the growth of RECs was observed.Growth curve of RECs under co-culture showed a lower growth rate in group A than in group B (P <0.05,dunnett's test),but no significant difference between group A and group C was noted (P>0.05,dunnett's test).RECs in group A proliferated muchfaster during the first four days post-transfection.Conclusion:Delivery of siRNA targeting VEGF plays an efficient role in down-regulating VEGF expression in RPE cells,therefore modulating the growth activity of RECs under a co-culture system in vitro.The application of this technique may provide novel evidence for the preventi展开更多
A light-controlled oscillating array for retina prosthesis is presented.The unique advantage of the circuit is that it has a lower voltage and ultra-low power consumption.And it has some other features as below:it is ...A light-controlled oscillating array for retina prosthesis is presented.The unique advantage of the circuit is that it has a lower voltage and ultra-low power consumption.And it has some other features as below:it is applicable to the natural light illumination and each pixel is an independent oscillator whose frequency is proportional to the intensity of the incident light.The fundamental characteristics of the circuit are analyzed.It is fabricated with a standard 0.6 μm CMOS technology.The experimental results indicate that the proposed circuit can be used for retina implantation,taking the place of the suffered photoreceptor in the retina of the blind and partially recovering the blind,s eyesight.展开更多
文摘Purpose:To investigate the effect of small interfering RNA (siRNA)targeting VEGF of retinal pigment epithelium (RPE) cells on the growth activity of human retinal vascular endothelial cells (RECs) under a co-culture system.Methods:By applying the vector.(pGPU6)-based siRNA plasmid gene silence system,we specifically silenced VEGF expression of RPE cells (ARPE-19) through plasmid (pG-PU6-VEGFA-siRNA)transfection.Reverse transcription polymerase chain reaction(RT-PCR) was applied for selecting the most efficient siRNA segment among three pGPU6-VEGF-siRNA groups (siRNA-1,siRNA-2 and siRNA-3).Treated RPE cells were co-cultured with RECs in a co-culture system made up of a 24-well culture plate and transwell inserts assembled inside During 7-day culture period,the growth ca-pacity of RECs were observed and tested in the form of cell counting assay.Three groups were established in this study:RPE cells transfected with pGPU6-VEGF-siRNA and co-cultured with RECs (group A),RPE cells transfected with siR-NA null vector and co-cultured with RECs (group B),and RECs cultured alone (group C).Results:After transfection,VEGF expression levels of RPE cells in three pGPU6-VEGF-siRNA groups (siRNA-1,siR-NA-2 and siRNA-3)evaluated by RT-PCR were 2.56 ±0.45,1.17 ±0.38 and 4.39 ±0.51,respectively (n =10).siRNA-2 was selected as the foremost segment for transfection (P < 0.05,SNK-q test).During the 7-day co-culture period,the influence upon the growth of RECs was observed.Growth curve of RECs under co-culture showed a lower growth rate in group A than in group B (P <0.05,dunnett's test),but no significant difference between group A and group C was noted (P>0.05,dunnett's test).RECs in group A proliferated muchfaster during the first four days post-transfection.Conclusion:Delivery of siRNA targeting VEGF plays an efficient role in down-regulating VEGF expression in RPE cells,therefore modulating the growth activity of RECs under a co-culture system in vitro.The application of this technique may provide novel evidence for the preventi
基金supported by the National Natural Science Foundation of China (Nos. 30470469 and 60702007)
文摘A light-controlled oscillating array for retina prosthesis is presented.The unique advantage of the circuit is that it has a lower voltage and ultra-low power consumption.And it has some other features as below:it is applicable to the natural light illumination and each pixel is an independent oscillator whose frequency is proportional to the intensity of the incident light.The fundamental characteristics of the circuit are analyzed.It is fabricated with a standard 0.6 μm CMOS technology.The experimental results indicate that the proposed circuit can be used for retina implantation,taking the place of the suffered photoreceptor in the retina of the blind and partially recovering the blind,s eyesight.