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)
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.
PURPOSE:To measure the concentration changes of tumor necrosis factor a (TNF-alpha;)in vitreous during the development of experimental PVR induced by macrophages and explore the initial and mediated factors which stimulate the cellular proliferation. METHODS:Rabbit PVR model was induced by macrophages and the vitreous was taken at the 7th,14th,21st and 28th day and 4 eyes in each group. The TNF-alpha; levels in vivreous of the above examinated and control eyes were measured with an ELISA kit. RESULTS:The TNF-alpha; level in the vitreous reached its peak 434mu;g/ml at 21st day in the mod-el, then rappidly decreased to 122mu;g/ml at 28th day. CONCLUSION:The changes of TNF-a in the vitreous of the PVR model were parallel to the natrual phases of the development of PVR,indicating TNF-alpha; may play an important role in initiating and mediating the inflammation and cellular proliferation in the vitreous. (Chin J Ocul Fundus Dis,1997,13: 231-233)
Objective To observe the suppressive effect of co mbi nation of tissue plasminogen activator (t-PA), heparin and homoharringtonine on the formation of proliferative vitreoretinopathy (PVR) after vitreoretinal surgery. Methods Forty-three cases (44 eyes )of complicated retinal detachment who received vitreoretinal surgery were divided into 2 g roup s.Twenty cases(20 eyes)in group A were treated by intravitreal injection of abo ve mentioned drugs at the end of operation,while no intraocular injection of drugs given in 23cases(24 eyes)in group B.The mean follow-up period was 7.9 months. Result The rate of recurrent PVR in group A was 15.8%(3 of 19),and 45.5%(10 of 22) in group B (P<0.05). The rate of recurrent retinal detachment was 5.5%(1 of 18) in group A,an d 33.3%(7 of 21) in group B,in group B(P<0.05). Conclusion Combination use of the above mentioned drugs can effectively suppress the post operative recurrent PVR and lower the rate of subsequent recurrent retinal detac hment. (Chin J Ocul Fundus Dis, 2001,17:24-25)
Objective To observe the surgical effects of photocoagulation and vitrectomy on familial exudative vitreoretinopathy (FEVR). Methods The data from 32 eyes of 17 patients with FEVR diagnosed in our department from January 1997 to August 2005 were analyzed retrospectively. The methods of treatment had been chosen according to the disease extents. Seven eyes ( stage 1 in 2 eyes, 2A in 1 eyes, and 2B in 4 eyes) had undergone peripheral photocoagulation with the follow-up period of 6-108 months (the average was 20.29 months); vitrectomy had been performed on 13 eyes(stage 3B in 2 eyes,4A in 1 eyes, 4B in 6 eyes, and 5A in 4 eyes) with the follow-up period of 3-108 months ( the average was 20.65 months); 12 eyes had received none of the treatments due to the serious extents, age, and the selection of the patientsprime; relations. Results In 7 eyes treated with peripheral photocoagulation, the disease was stable and visual acuity remained unchanged during the follow-up period . In 13 eyes undergone vitrectomy, reattached retina was found in 12; visual acuity improved in 9, kept still in 3, and was unknown in 1 because of the patient prime;s noncooperation. Conclusion Photocoagulation may prevent the development of FEVR, and vitrectomy can promote the reattachment of retina and improvement of the visual acuity in patients with FEVR. These two treatments are effective on FEVR. (Chin J Ocul Fundus Dis,2006,22:302-304)
Objective To observe the expression of vascular endothelial growth factor (VEGF) in aqueous humor and vitreous body in eyes with proliferative vitreo-retinal diseases, and to investigate the role of VEGF plays in the pathoge nesis of proliferative vitreo-retinal diseases. Methods The concentration of VEGF in aqueous humor and vitreous body in eyes with proliferative vitreoretinopathy (PVR), retinal vein occlusion (RVO), proliferative diabetic retinopathy (PDR), and neovascular glaucoma (NVG) were measured by double antibodies sandwich enzyme-linked immunosorbent assay (ELISA). Results The concentration of VEGF in aqueous humor and vitreous body in eyes with PVR, RVO, PDR and NVG were obviously higher than that in the control group (Plt;0.05), respectively. Among all of the diseases, the concentration of VEGF in aqueous humor and vitreous body decreased orderly in NVG, PDR, RVO and PVR (Plt;0.05). The concentration of VEGF in vitreous body in eyes with PVR, RVO, PDR and in the control group were much higher than that in aqueous humor in corresponding groups (Plt;0.05). There was a negative correlation between the disease history and content of VEGF in aqueous humor and vitreous body in patients with PVR (r=-0.819, -0.823;Plt;0.05). The disease history positi vely correlated with the concentration of VEGF in aqueous humor and vitreous body in patients with RVO (r=0.913, 0.929;Plt;0.05), and the time of vitreous hemorrhage positively correlated with the concentration of VEGF in aqueous humor and vitreous body in patients with PDR (r=0.905, 0.920;Plt;0.05). Conclusion The concentration of VEGF in aqueous humor and vitreous body in patients with proliferative vitreo-retinal diseases significantly increases, and VEGF may play an important role in the pathoge nesis of proliferative vitreo-retinal diseases. (Chin J Ocul Fundus Dis, 2006, 22: 313-316)
Objective To observe the effect of medicineinduced posterior vitreous detachment (PVD) on proliferative vitreoretinopathy (PVR). Methods PVR was induced in the left eyes of 24 pigmented rabbits by intravitreal injection with platelet rich plasma. The rabbits were randomly divided into two experimental groups (group A and B) and one control group with 8 eyes in each group. Three hours later, the eyes in group A and B and the control group underwent intravireal injection with 1 U plasmin 0.05 ml+20 U hyaluronidase 0.05 ml, plasmin 0.1 ml, and balance salt solution 0.1 ml, respectively. The grade of PVR was recorded 1, 7, and 28 days after the intravitreal injection, and the eyes were examined by flash electroretinogram (FERG), B-scan, and retinal histopathological examination. Results The PVR models of rabbit eyes were induced successfully. On the 7th day after injection, complete and partial PVD was found in 5 and 3 eyes respectively in group A; partial PVD in 5 eyes and no complete PVD was observed in group B; there was no PVD in the other 3 eyes in group B and also in the eyes in the control group. On the 28th day after intravitreal injection, PVR grade of group A and B were both obviously lower than that of the control group(D=75.6, 98.9;P=0.003,P=0.011); On the 7th and 28th day after injection, the b-wave amplitude in group A and B was significantly higher than that in the control group; PVR grade of the PVD eyes was lower than that of nonPVD eyes; PVR grade of the complete PVD eyes was only 0~1. Conclusions Three hours after the PVR models of rabbit eyes were induced, complete PVD induced by intravitreal injection of plasmin combined with hyaluronidase could prevent the development of PVR of rabbit eyes in some degree; partial PVD induced by plasmin alone or combined with hyaluronidase could relieve the development of PVR.
Objective To determine the concentration of int erleukin-12(IL-12),interleukin-2(IL-2) and tumor necrosis factor(TNF)and the irpossible role in the pathogenesis of proliferative vitreoretinopathy(PVR) . Methods Patients were divided into 3 groups:18 with PVR,7 with simples retinal detachment caused by macular hole and 4 samples from normal eyes were used as control.Sample s of vitreous were obtained by aspiration through pars plana before cryotherapy ,vitrectomy and gas injection and stored in liquid nitrogen at -70℃ within 30 minites for ELISA. Results ①The levels of IL-12,IL-2,and TNF in the vitreous of PVR were positively correlated with the degree of severity of disease.②The levels of IL-12, IL-2,and TNF in the PVR were higher than those in simple retinal detachment caused by macular hole and those in control group(Plt;0.01 ).③The levels of IL-12,IL-2,and TNF in retinal detachment caused by macular hole were also higher than those in the control group(Plt;0.01). Conclusion IL-12,IL-2,and TNF may play a role at lease to some extent in the pathogenesis of PVR. (Chin J Ocul Fundus Dis,1999,15:75-77)
Objective To observe whether apoptosis was involved in cells of aspiration fluid from vitrectomy for proliferative vitreoretinopathy(PVR),and whether there was an association with expression of Fas antigen(Fas )and Fas ligand (FasL). Methods Cytocentrifuge slides of 11 fresh vitreous specimens of PVR were prepared to be stained by TUNEL met hod for detection of apoptosis and by immunohistochemical technique for detection of Fas,FasL,and cytokeratin (CK),a cell-type specific antigen. Results Fas and FasL were expressed in normal human retina.Fas,FasL,CK,and apoptosis were found in all preparations.TUNEL-positive cells were 20.53% in total cells.70.35%,51.58%,and 82.97% of cells highly expressed Fas,FasL,and CK,respectively.The linear correlation coefficient of Fas and apoptosis was 0.99(Plt;0.001). Conclusion Vitrectomy specimens of PVR showed expression of Fas,FasL,and apoptosis.Prominent Fas and FasL expressions may be associated with apoptosis of proliferating retinal pigment epithelial cells in the vitreous of PVR. (Chin J Ocul Fundus Dis,1999,15:78-80)