ObjectiveTo observe the longterm effect of suramin on the inhibition of proliferation of human retinal pigment epithelial (RPE) cells in vitro. MethodsRPE cells grown in 9 pieces of 96well plate (12 wells each plate) were divided into experimental and control group, with 6 wells in each group. The concentration of 0.1 ml RPE cells in each well is 5×104 cells/ml. After the change of the medium, RPE cells were treated with suramin (250 μg/ml) in experimental group while treated with nothing in the control group. The medium of the 2 groups were changed to the normal medium after 4 days. At the 1st, 2nd, and 4thday after the addition of suramin and at the 1st, 2nd, 3rd, 5th, 6th, 7th, 9th , 11th and 13th day after removing suramin, 1 plate was randomly selected to stop culturing, and the proliferation of RPE cells were detected by methyl thiazolyl tetrazolium (MTT) assay. ResultsUnder reversed microscope, RPE cells in control group were fused completely at the 7th day after inoculation. The extracellular space of RPE cells in experimental groups was larger than that in the control group, and remained unfused at the 13th day after inoculation. The inhibitory rate of proliferation of RPE cells at the first day after treated with suramin was 14.85% and increased to the highest 25.79% at the 4th day. The first day after the suramincontaining media was removed, the inhibitory rate decreased to 12.35%, and then raised gradually to over 20% at the 3rd to 5th day. Finally, the rate drop to 14.71%. ConclusionSuramin has the long-term effect on the inhibition of RPE cells induced by serum, especially the inhibitive effect after the remove of suramin, which indicates the specific double-peak inhibition during the whole process.(Chin J Ocul Fundus Dis, 2005,21:25-27)
Objective To investigate the inhibitive effect of E2F decoy oligodeoxynucleotides (E2F decoy ODNs) on cultured human retinal pigment epithelial (HRPE) cells.Methods E2F decoy ODNs or scramble decoy ODNs at varied concentrations were put into the HRPE cells mediated by lipofectamineTM2000. The proliferative activity of HRPE was detected by methythiazolyl-terazollium assay, and the competitive combinative activity of E2F decoy ODNs and transcription factor E2F was detected by electrophoresis mobility-shift assay. Results The proliferation of HRPE was inhibited markedly by E2F decoy ODNs at the concentration of 0.2 μmol/L (P=0.002) in a dose-dependent manner but not by scrambled decoy. The results of electrophoresis mobility-shift assay showed that the combinative activity of transcription factor E2F was abolished completely by E2F decoy ODNs. Conclusions E2F decoy ODNs may sequence-specifically inhibit the combinative activity of transcripti on factor E2F,and inhibit the proliferation of HRPE cells.(Chin J Ocul Fundus Dis,2004,20:182-185)
Purpose To study the possibility of prevention of proliferative vitreoretinopathy(PVR) by transduction of exogenous gene in vivo. Methods PVR model of rabbits was induced by intravitreal injection of fibroblasts.beta;-galactosidase (lacZ) gene as a reporter gene was transfered into the vitreous of PVR model eyes mediated by retroviral vector, and the expression of the gene in eye tissues was determined . Gene transfection was done on the 6th day after fibroblasts injection,and the dosage of intravitreal injection of reporter gene was 0.1ml PLXSN/lacZ serum-free supernatant (1.1times;106 cfu/ml). Results lacZ gene expression was seen in proliferative membranes after gene transfection, and the expression was located maily at the surface of PVR membrane.The reporter gene expression lasted at least more than 30 days.No expression was found in retinal tissues. Conclusions Retrovirus mediated gene can be directionally transducted in PVR membrane,and might possess the feasibility of gene therapy for PVR. (Chin J Ocul Fundus Dis, 2001,17:224-226)
Proliferative vitreoretinopathy (PVR) is a common complication and major cause of blindness of ocular trauma. Many cytokines, including vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF), participate in the process of the pathogenesis of traumatic PVR. VEGF competitively inhibits binding of PDGF to its receptor (PDGFRα), enables indirect activation of PDGFRα by non-PDGF ligands, resulting in reduced p53 expression, cell proliferation and migration, which is a key point in the pathogenesis of traumatic PVR.
ObjectiveTo analyze the color Doppler flow imaging (CDFI) features of familial exudative vitreoretinopathy (FEVR) at different stages. MethodsA retrospective study. A total of 104 patients with 201 eyes from Department of Ophthalmology of Beijing Tongren Hospital who were hospitalized for fundus examination and diagnosed with FEVR from 2018 to 2022 were included. There were 69 male cases with 133 eyes and 35 female cases with 68 eyes. The age was ranged from 2 months to 11 years, with a mean age of 2.9 years. Fundus and CDFI examination were performed in both eyes. Fluorescein fundus angiography was performed in 72 cases (144 eyes). FEVR staging was conducted according to literature standards. The presence of avascular areas in the peripheral retina or abnormal retina neovascularization was stage 1; the presence of retinal neovascularization at the vitreoretinal interface in the avascular area was stage 2; partial retinal detachment without macula involvement was stage 3; partial retinal detachment involving the macula was stage 4; complete retinal detachment was stage 5. The CDFI ultrasound features of FEVR at different stages were analyzed. The CDFI image features of FEVR patients in different stages were observed. ResultsAmong the 104 patients, 97 (93.3%, 97/104) cases were binocular and 7 (6.7%, 7/104) cases were monocular. In 201 eyes, stages 1 to 5 of FEVR were 49 (24.4%, 49/201), 23 (11.4%, 23/201), 39 (19.4%, 39/201), 71 (35.3%, 71/201), and 19 (9.5%, 19/201) eyes, respectively. CDFI examination showed no abnormality or mild vitreous opacity in 49 eyes vitreous body at stage 1. Vitreous opacities were observed in all 23 eyes in stage 2, and the echo of the temporal ballwall was not smooth. In 39 eyes at stage 3, the anterior globular cluster echo in temporal peripheral eyes was observed in 17 eyes and partial retinal detachment was observed in 13 eyes. In 71 eyes at stage 4, 51 eyes had temporal or infratemporal retinal folds, and 20 eyes had temporal retinal detachment. All the 19 eyes in stage 5 had total retinal detachment, of which 15 eyes had closed "funnel-shaped" retinal detachment. Among the patients with retinal folds, 13 had bilateral folds, and the fellow eyes of the other 25 patients with unilateral folds all had vitreous opacity or clump echo in front of the temporal spherical wall. Blood flow signals could be detected on the retinal folds with Doppler imaging. ConclusionsThe CDFI manifestations of FEVR patients at different stages have different characteristics. The possibility of FEVR should be considered when the temporal or infratemporal retinal folds of both eyes are present, as well as the retinal folds of one eye, the contralateral vitreous body opacity, or the anterior temporal peribulbar cluster echoes are present.
Objective To investigate the occurrence, progress and conversion of hypotony in anterior proliferative vitreoretinopathy (aPVR), and to provide knowledge about how to prevent and treat it. Methods Animal models of chronic hypotony by aPVR were made with cultured ho mologous dermal fibroblasts on pigmented rabbits.The intraocular pressure (IOP) and ultrasound biomicroscopy(UBM) examination were taken preoperatively and on days 7,14, 28 and 56 postoperatively.Rabbits were killed on days 14, 28 or 56 postoperatively, prepared for histology and ultrastructure examination. Results The average IOP of experimental group was lower than that of control group on days 7,14,28 and 56 significantly (Plt;0.01).UBM demonstrated that trip like echo emerged in front of ciliary body four weeks postoperatively, and tractional retinal detachment was found four weeks and eight weeks postoperatively in experimental group. Microscopic examination showed atrophy orabsence of the non-pigmented ciliary epithelium on days 28 and 56 postoperatively in experimental group.Electronic microscopy showed that the amount of mitochondrions decreased and there were many vacuoles in the non-pigmented ciliary epithelium in experimental group four and eight weeks postoperatively. Conclusions Atrophic change of the non-pigmented epithelium due to dragging effect of the ciliary body from the epiciliary membrane in aPVR might be the main cause of hypotony. (Chin J Ocul Fundus Dis, 2001,17:216-220)
Objective To investigate the therapeutic effects of subconjunctival verapamil on outcome in an experimental model of traumatic proliferative vitreoretinopathy. Methods An experimental model of traumatic proliferative vitreoretinopathy was induced in pigme nt rabbits,which then were selected randomly to receive either subconjunctival verapamil injection treatment or a placebo injection(control)daily for 3 weeks.Animals were examined by indirect ophthalmoscopy at weekly intervals for 5 weeks. Eyes were enucleated for light microscopy 5 weeks later. Results Fifty-six percent(18 of 32)of the rabbits receiving subconjunctival verapamil injection had developed tractional retinal detachment,whereas eighty-one percent(26 of 32)of control animals had developed tractional retinal detachment(chi;2=4.655,P=0.031).The results of clinical examination and light microscopy didn't show evidence of toxicity between the verapamil treated animals and control animals. Conclusion Subconjunctival verapamil decreased the incidence of tractional retinal detachment due to traumatic proliferative vetreoretinopathy in this rabbit model.Verapamil at the dose used in this model has no evident toxicity on rabbit eyes.Further studies are needed to determine the doseresponse and efficacy of the drug. (Chin J Ocul Fundus Dis,1999,15:69-71)