Objective:To observe the inhibited effect and its mechani sm of estro gen on lightinduced apoptosis of retinal photoreceptor cells. Methods:Twenty female Sprague-Dawley rats were randomly divided into two groups: ovariectomized (OV) group and OV and estrogen (E2) replacement (OV+E2) group, with 10 rats in each group. All of the rats were exposed to the cyclic illumination under 12 hou r light and 12 hour dark condition with the light intensity of (600plusmn;35.4) lx ( a total of 14 times). All of the right eyes were extracted and the thickness of r etinal outer nuclear layer (ONL) was measured. Terminal deoxynucleotidyl Transfe rasemediated dUTP nick end labeling (TUNEL) method was used to evaluate positi v e apoptosis cells in ONL. The expression of nitric oxide synthase (NOS) in retin al cells was detected by immunohistochemistry with image analysis method. Results:The thickness of ONL in OV group was obviously thinner than that in the OV+ E2 group. The number of positive apoptosis of the cells was (0.0275plusmn;0.0069) c el ls/mu;m2 in OV group and (0.0162plusmn;0.0054) cells/mu;m2 in OV+E2group; the di fferen ce between the two groups was significant (t=4.1370，P=0.0012). The values o f in tegral optical density of NOS positively stained cells in retinal inner nuclear layer was (0.3675plusmn;0.0662) in the OV group and (0.2941plusmn;0.0350) in OV+E2 group ; the difference between the two groups was significant (t=3.4885, P=0.0031). Conclusion:Estrogen can protect retina from light injuries by regu lating NOS synthesis and inhibiting apoptosis of photoreceptor cells.
ObjectiveTo discuss the role and effect of the triamcinolone acetonide (TA) injection applied in the vitreoretinal surgery for assisting to distinguish and removal residual cortex.MethodsOne thousand and forty-six patients (1 056 eyes) underwent a PPV at West China Eye Center from August 2003 to February 2005. These affected eyes were selected without posterior vitreous detachment pre-and intra-operatively, and underwent intravitreal injection with TA 1-2 mg to label the residual vitreous cortex on the surface of the posterior retina after removal of the majority vitreous.ResultsThe location and coverage of the residual vitreous cortex were clearly be shown by the white appearance of TA labeled residual vitreous, and the residual vitreous cortex was conveniently to be recognized and removed.ConclusionThe application of intravitreal injection with TA is helpful for identification and elimination of the residual vitreous cortex in vitreoretinal surgery.(Chin J Ocul Fundus Dis, 2005,21:226-228)
ObjectiveTo observe the inhibitory effect of endostatin (ES) on oxygen-induced retinal neovascularization.MethodsThirtyfour 7-day-old C57BL/6J mice were randomly divided into 3 groups: oxygen-exposed group (12 mice), ES group (12 mice) and the control group (8 mice). The mice in oxygen-exposed and ES group were exposed to (75±5)％ oxygen for 5 days and then back to the normal air. In ES group, 1 μg ES endostatin were injected into vitreous in one eye, while PBS was injected into the other eye as the control 12 and 36 hours after being exposed to oxygen. The mice in the control group were fed in normal circumstance. The changes of retinal neovascularization was examined by fluorescence angiography with fluorescein isothiocyanatedextran. The number of endothelial cells breaking through the internal limiting membrane (ILM) was counted and the inhibitory effects of ES on retinal neovascularization was observed.ResultsCompared with the oxygen-exposed group, the branches of retinal vessels went normal without any un-perfused area in ES group. The number of nuclei of endothelial cells breaking through ILM on each retinal crosssection decreased to (5.39±1.52), which differed much from that in the oxygen-exposed group (22.56±2.13) (plt;0.001).ConclusionES can effectively inhibit the formation of retinal neovascularization in rats and might be a new path of the treatment for proliferative retinopathy.(Chin J Ocul Fundus Dis, 2005,21:314-317)
Objective To observe the effect of blue light on apoptosis of cultured human retinal pigment epithelial (RPE) cells in vitro. Methods Human RPE cells were exposed to blue light, and the cells were divided into 3 groups: group A, with various intensity of illumination; group B: with same intensity but different time of illumination; group C: with same intensity and time of illumination but different finish time of the culture. The apoptosis of RPE cells was observed by TdT-dUTP terminal nick-end labeling (TUNEL) and annexin V-fluoresein isothiocyanate (FITC)/propidium iodide (PI) flow cytometry, and transmission electron microscopy. Results The positive cells stained by TUNEL shrinked and turned round, whose nuclei concentrated and congregated like the crescent or hat. Cracked nuclei and membrane bleb were found. Swollen mitochondrial, disappeared inner limiting membrane of mitochondria, and dilation of the rough endoplasmic reticulum with metabolite were observed by transmission electronmicroscopy. In group A, mild damage of RPE cells was found when the threshold value of the intensity of illumination was less than（500±100）lx, and the apoptosis and necrosis of RPE cells aggravated as the intensity of illumination increased; in group B, as the time of illumination extended, the number of apoptotic RPE cells didn′t increase while the necrosis increased; in group C, 6 and 12 hours after illumination, apoptosis of cells was the main injury, while apoptosis with necrosis was found and necrotic cells increased as the time of illumination was prolonged. Conclusions Illumination with blue light may cause damages of human RPE cells in vitro, with the modalities of apoptosis, apoptotic necrosis and necrosis. The extent of injury is dependent on intensity and duration of the illumination. (Chin J Ocul Fundus Dis, 2005, 21: 384-387)
Objective To study the inhibitive effect of adenovirus mediated CD gene and 5-FC on proliferative human retinal pigment epithelial (HRPE) cells, and to search for an effective method to take precautions against proliferative vitroretinopathy (PVR).Method Different concentrations of CD and 5-FC were added respectively to the cultured third-growth-generation HRPE cells.Transferance rate was detected by positive HRPE cells marked by X-gal and LacZ. The number of HRPE cells were counted and evaluated by methylthiazol-tetrazollium (MTT) method. Results The adenovirus mediated CD gene could be transfered into HRPE cells with a dose-dependent manner. Positive HRPE cells with CD gene could transform 5-FC to 5-Fu,which could inhibit the increase of HRPE cells effectively. No obvious bystander effect on the growth of HRPE cells was detected.Conclusions The adenovirus may introduce a foreign gene into cultured HRPE cells efficiently. It could be a good method to treat and prevent PVR by medication. (Chin J Ocul Fundus Dis，2003，19：168-171)
Objective To observe the effect of exogenous basic fibrob last growth factor (bFGF) on apoptosis of cultured human retinal pigment epithelial (RPE) cells exposed to visible light,and determine the role of bFGF, fibroblast growth factor receptor 1 (FGFR1),bcl-2 and caspase-3. Methods 2000±500) lx cold white light was used. Exogenous bFGF was utilized during culture. Annexin annexin V-fluoresce in isothiocyanate/propidium iodium (V-FITC/PI) labeling,flow cytometry, Immunocytochemical staining, enzyme associated absorb examing and reverse transcriptional polymerase chain reaction (RT-PCR) were used to determine the apoptosis, the expression levels of bFGF, FGFR1, bcl-2, as well as the activity of caspase-3. Results No protective effect of bFGF was observed under the concentration 5 ng/ml.A significant inhibition of apoptosis was found in 10 ng/ml and 20 ng/ml groups （P＜0.05）. The upregulation of bcl-2 was observed in bFGF (10 ng/ml, 20 ng/ml) protreated groups（P＜0.01）.Compared to no light exposure group,all light exposure groups (including bFGF pro-treated) had higher endogenous bFGF and FGFR1 levels （P ＜0.05）, and the increase was concentration dependent.The bFGF and FGFR1 levels were higher in exogenous bFGF applied (gt;5 ng/ml) groups than light exposure groups（P＜0.05）. The caspase-3 activity was significantly inhibited in bFGF (10 ng/ml) pro-treated groups. Conclusions Human RPE cells exposed to visible light were rescued by application of exogenous bFGF in vitro.The probable protective mechanism of bFGF partly is directly binding to FGFR1 or potentiating endogenous bFGF autocrine loop,to upregulate bcl-2 and to inhibit caspase-3 activation. (Chin J Ocul Fundus Dis，2003，19：24-28)
Objective To detect expression of NF-κB in the inner retina and in vestigate the inhibitoryeffect of pyrrolidine dithiocarbamate on retinal neovascularization in rats. Methods The rat models with retinopathy were set up un der the hypoxia condition, and fluorescein fundus angiography (FFA) was used to observe the retinal neovascularization. The expressions of NF-κB in the inner retina in rats with and without neovascularization were detected by immunohisto chemical method. PDTC was intraperitoneally injected in rats with neovascularization to observe the expression of NF-κB in the inner retina and the effect on retinal neovascularization. Results Hypoxia induced NF-κB activation in the retinal glial cells and endothelial cells. But immuno-staining intensity for NF-κB and adhesion molecules were reduced by PDTC intraperitoneal injection. Retin al angiogenesis in rats were suppressed effectively (P＜0.05). Conclusions NF-κB activation correlates with retinal neovascularization closely. PDTC may inhibit the NF-κB activation and prove beneficial in the treatment of ischemic neovascularization. (Chin J Ocul Fundus Dis，2003，19：201-268)
Objective To observe the effect of visible light on apoptosis of cultured human retinal pigment epithelium (RPE) cells. Methods Being the light source,500lx,(2 000±500)lx and (3 400±200)lx cold white light were used. The duration of exposure was 0,6,12 and 24 hours respectively. Apoptosis was detected by terminal deoxynucleotidyl transferase mediated dUTP nick end labelling, Annexin V-flunorescein isothiocyanate/Propidium iodium labelling and flow cytometry. Results Apoptosis and necrosis were found in cultured human RPE cells which were exposed to visible light.(1)A significant increase in apoptotic and necrotic percentages was consistent with a higher light intensity.(2)Apoptosis was the main response to shorter (6 h and 12 h) exposure duration,while necrosis was more pronounced correlated to the prolongation of post-exposure culture (P＜0.05),and the longer the post-exposure period was, the more apoptotic necrosis were seen.Thirty-six hours after exposure the necrotic percentages were more pronounced (P＜0.01). Conclusions Visible light (＞500 lx) increases the proportion of apoptosis and necrosis of human RPE cells in vitro.The extent is related to exposure intensity and duration. It demonstrates that the lower intensity and the shorter duration of exposure to light are, the more pronounced apoptotic percentages are observed,otherwise necrosis. (Chin J Ocul Fundus Dis, 2002, 18: 227-230)
Objective lt;brgt;To study the clinical results and safty of photodynamic therapy (PDT) after single and multi-treatments of patients with subfoveal choroidal neovascularization (CNV) caused by wet agerelated macular degeneration (AMD). lt;brgt; lt;brgt;Methods lt;brgt;From July, 2000 to July, 2001, 20 wet AMD patients (31 eyes) 4788 years old (mean 68.2 years old) with best-corrected visual acuity from FC/10 cm to 0.6 diagnosed through optic coherence tomography (OCT), fluorescein angiography (FFA) and indocyanine green angiography (ICGA) were treated with PDT. All cases were assigned to benzoporphyrin derivative mono acid (BPD) (6 mg per square meter of body surface area), administered via intravenous infusion of 30 ml over 10 minutes. Fifteen minutes after the start of the infusion, a laser light at 689 nm (Zeiss company, German) delivered 50 J/cm2 at an intensity of 600 mW/cm2 over 83 seconds on CNV. Visual acuity, photochrome of ocular fundus, OCT, FFA, ICGA were used to evaluate the effects of photodynamic therapy with BPD. Follow-up of these patients was planned 1-2 week and every 3 month after PDT. Once the lesion area progressed, PDT was applied again. Tweenty cases (31 eyes) were followed up from 3 to 18 months (average 12 month).In 1 affected eye, PDT was applied fow 4 times, 4 eye for 2 times, and the other 26 eyes for 1 time. lt;brgt;Results lt;brgt;The visual acuity in 13 (41.9%) eyes was improved (increase≥2 lines) after PDT. Stabilized (±1 line) in 17 (54.8%) eyes and decreased 2 lines（attributed to the recur of CNV ）in 1 (3.2%) eye. After PDT, the fundus haemorrhage and fluid leakage reduced. FFA and ICGA showed. cessation and obvious reduction of fluorescein leakage from CNV in all patients 2 weeks after photodynamic therapy, and retreatment decreased the leakage step by step. Fluorescein leakage from at least a portion of the CNV reappeared by 1-3 month after treatment in some cases. OCT also showed the reduction of the size of CNV, moreover, the edema of surrounding retina and choriodal and serous neural epithelial detachment recovered obviously. No side affect during and after PDT was noticed. lt;brgt;Conclusions lt;brgt;PDT with BPD can achieve short-term effect on part or total cessation of fluorescein leakage from CNV without loss of vision or growth of classic CNV in patients with age-related macular degeneration, retreatment of PDT was also effective. lt;brgt; lt;brgt;(Chin J Ocul Fundus Dis, 2002, 18: 175-179)
Objective lt;brgt;To investigate the morphological features of choroidal neovascularization (CNV) in central exudative chorioretinopathy (CEC) using optical coherence tomography（OCT）. lt;brgt; lt;brgt;Methods lt;brgt;OCT and fundus fluorescein angiography (FFA) were performed in 41 cases (43 eyes) of CEC,and the course of CEC disease was from 1 week to 10 months. Twenty-seven of 43 eyes were also examined by indocyanine green angiography (ICGA). lt;brgt; lt;brgt;Results lt;brgt;OCT images revealed 5 kinds of morphological features of CEC: well-defined CNV（41.86 %）,poorly-defined CNV(30.23 %),hemorrhagic pigment epithelium detachment （PED）(16.28 %), CNV companied with serous (6.98 %) or hemorrhagic neurosensory retina detachment (4.65 %). CNV mainly showed well-defined and poorly-defined CNV (72.09 %).In those eyes that could clear define the CNV boundary,there were 12 eyes on FFA examination and 20 eyes on ICGA examination which defined the boundary from retinal horizontal plane, while there were 23 eyes on OCT examination which defined the boundary from retinal vertical section. Classic CNV on FFA consistently presented with well-defined boundaries on OCT, whereas non-classic CNV had a variable cross-sectional appearance. lt;brgt; lt;brgt;Conclusions lt;brgt;The OCT morphological features of CNV in CEC is mainly well-defined CNV and poorly-defined CNV; OCT examination can precisely observe the retinal and choriocapillaries pathological anatomy of CEC from retinal vertical section, in making the CEC diagnosis as an important complementary examination of FFA and ICGA which observe the focus from retinal horizontal plane. lt;brgt; lt;brgt;(Chin J Ocul Fundus Dis, 2002, 18: 121-124)