Objective To investigate the early effects of intervention with tanakan on retinal function in diabetic retinopathy(DR) after laser photocoagulation. Methods Prospective random controlled study was performed on 60 Patients (60 eyes) from 23 to 69 years old with DR(phase Ⅲ～Ⅳ). The multifocal electroretinograms (MERG) were tested with VERIS Ⅳ before, the 3rd day and the 7th day after photocoagulation. Results No significant differences were found in the latencies and response densities of N1,P1 and N2 between the two groups before photocoagulation. Compared with that before photocoagulation, three days after photocoagulation the latencies in tanakan group had no significant change. The response densities of N1,P1 and N2 reduced and the changes were much smaller than that in control. Three days after photocoagulation, the response densities of P1 and N2 in the central macula 5°area were much higher and the latencies of P1 and N2 were significantly shorter than that in control group. There were no significant differences in the response densities in the 7th day and the differences in the latencies between two groups still existed. Conclusion Tanakan may be effective in preventing the retina from damage of retinal photocoagulation in some degree in DR. (Chin J Ocul Fundus Dis, 2002, 18: 208-211)
Objective To inverstingate the effect of perfluorohexyloctane(F6H8)to the retina of rabbit eyes. Methods Fifteen vitrectomized New Zealand white rabbits were injectedF6H8(experiment group,12 rabbits ) and BSS(control group,3 rabbits) into vitreous cavity.Slit-lamp biomicroscopy and indirect ophthalmoscopy were performed pre- and postoperatively in all the eyes.Histopathological examination was done after the rabbits were sacrificed at the end of the study. Results A large clear balb was formed after intravitreal injection of theF6H8 in the vitreous was injected and no retinal detachment and cataract were found.The OPL was edematous and then thinned out in 4th week in experimental group.Degenerating cells was found in inner and outer nuclear layers.Cellular vaculoar degeneration was present in TEM. ConclusionF6H8 in vitreous cavity may cause significant side effects on retina,we could not recommend it to be used as an intraocular temponade.
Objective To evaluate the therapeutic effect of intravitreal injection with bevacizumab (Avastin) (IVB)combined with extra panretinal photocoagulation (E-PRP) for highrisk proliferative diabetic retinopathy (PDR).Methods A total of 57 eyes of 53 patients with highrisk PDR underwent intravitreal injection combined with E-PRP. The examinations of vision acuity, intraocular pressure, iris fluorescein angiography (IFA),fundus photos and fundus fluorescein angiography (FFA) were performed on all of the patients before and 1,2,3,and 6 months after the treatment; the results of the examinations before and after the treatment were compared and analyzed.The average follow up was 6 months.Results The mean visual acuity was (0.143plusmn;0.072) before the treatment and (0.218plusmn;0.128) 7 days after the tretment; the difference was significant (t=-7.940, Plt;0.05). The mean visual acuity 1,3,and 6 months after E-PRP (0.228plusmn;0.138, 0.223plusmn;0.125,0.220plusmn;0.134, respectively) differed much from that before IVB (Plt;0.05), but not so much from that after IVB (Pgt;0.05).The mean intraocular pressure of 21 eyes which had the neovascularization of pupil margin and iris surface before and 7 days after IVB was (26.632plusmn;2.629) and (19.316plusmn;3.092) mm Hg(1 mm Hg=0.133 kPa), respectively; the difference was significant (t=12.838, Plt;0.05) . The mean intraocular pressure 1,3,and 6 months after E-PRP was (16.947plusmn;2.345),(16.474plusmn;1.611), and (16.421plusmn;4.702) mm Hg, respectively, which differed much from that before and after IVB (Plt;0.05). Neovascularization on the disc and the retinae of 57 eyes were subsided partly, and a significant reduction or disappeared of the area of retinal neovascularization and the blood vessel leakage were observed 7 days after IVB. The neovascularization of pupil margin and iris surface of 21 eyes disappeared, and the IFA leakage decreased. The results of FFA 2 months after E-PRP showed that the one-off efficiency of E-PRP was 68.4%;12 eyes (21.1%) needed an additional laser, in which 6 eyes (10.5%) underwent vitreous surgery. Conclusion IVB combined with E-PRP as a treatment for highrisk PDR may improve the regression of retinal neovascularization and the reduction of vascular permeability,and prevent or reduce the complications and improve the therapeutic effect.
OBJECTIVE:To observe the effect of dexamethasone to intracellular free Ca2+ of frozen RPE cells. METHODS:The cultured human RPE cells were frozen for 30s at --70deg;C. The RPE cells were loaded with Fura-2/AM and analyzed using a digital imaging microscopy system,the effect of dexamethasone to intracellular free Ca2+ was measured at a serial concentration of 40, 60,100,150,200mu;g/ml. RESULTS:The concentration of intracellular free Ca in frozen human RPE cells was increased to 18.6%~29.8% by dexamethasone at concenlration of 40mu;g/ml~60mu;g/ml,while was decreased to 28.4%~35.2% at 150mu;g/ml~200mu;g/ml. CONCLUSIONS:Effect of dexamethasone showed two aspects of effect to frozen cultured human RPE ceils,that it was inhibitor at high concentration and stimulator at low concentration （Chin J Ocul Fundus Dis,1997,13: 86-88）
Objective To investigate the protective effect of Niacin on blood-retina barrier (BRB) in diabetic rats and related mechanism. Methods The male Wistar rats (60) were divided into control (CON) group, diabetes (DM) group and Niacin-treated (NA) group, 20 rats in each group. Rats diabetes models were induced with streptozotocin injection. Niacin (40 mg/kg·d) was administrated orally everyday in Niacin-treated group until sacrificed after 3 months. Pathological outcomes, total cholesterol (TC) and high-density lipoprotein (HDL) were evaluated at month 3. Optical microscopy was used to observe the retinal structure. The integrity of BRB and the vascular permeability was quantified by analyzing albumin leakage using Evans blue (EB) method. The relative expressions of Claudin-5, Occludin, zonula occluden (ZO)-1 and GPR109A mRNA in rat retinas were detected by reverse transcription PCR (RT-PCR) and relative expression of GPR109A, tumor necrosis factor (TNF)-α and interleukin (IL)-6 by Western blot. Results Compared to CON group, the TC content was increased and HDL content was decreased in DM group (t=4.034, 5.831; P < 0.05). Compared to DM group, the TC content was decreased and HDL content was increased in NA group (t=6.868, 3.369; P < 0.05). The retinal structure of CON group was normal. Pathological changes were found in the DM group, such as tumescent nuclei and disorganized structures. The retinal structure of NA group was similar to the control group. Evans blue dye that the microvascular leakage in DM group was increased compared with CON group (t=24.712, P < 0.05), while in NA group was decreased compared with DM group (t=16.414, P < 0.05). The mRNA expression of Occludin, Claudin-5, ZO-1 in DM group were decreased compared with CON group (t=11.422, 12.638, 12.060; P < 0.05), while in NA group were increased compared with DM group (t=5.278, 3.952, 8.030; P < 0.05). The mRNA expression of GPR109A in NA group were increased compared with DM group (t=5.053, P < 0.05). The protein expression of GPR109A, IL-6, TNF-αin DM group were increased compared with CON group (t=4.915, 11.106, 6.582; P < 0.05). Compared to DM group, the protein expression of GPR109A was increased (t=5.806, P < 0.05), while the protein expression of IL-6 and TNF-α were decreased (t=10.131, 5.017; P < 0.05). Conclusion Niacin has the protective effect for BRB by up-regulating GPR109A expression which may suppress inflammation.
Objective To detect the clinical manifestations, diagnos is and treatment of painful ophthalmoplegia syndrome. Methods The data of onset, clinical m anifestations, laboratory examination, imaging and treatment from 12 patients with painful ophthalmoplegia, hospitalized from Mar, 2000 to Aug. 2005, were retro spectively analyzed. Results Multiple characters and extents of the headache were found in these 12 patients. The involved cranial nerves included the Ⅲ,Ⅳ, V1-2 and Ⅵ, especially the cranial nerve Ⅲ(83.3%). Several simultaneously in volved cranial nerves were frequently found (75%). Diseases which could cause hea dache along with ophthalmoplegia must be excluded before the diagnosis of the painful ophthalmoplegia syndrome was established. The examination of imaging was important for the diagnosis of painful ophthalmoplegia syndrome. Patients were sensitively responsive to cortico-steoid therapy. The cure rate was 75%. Conclusion The features of clinical manifestations, imaging results and the patients response to cortico-steoid therapy accorded with the etiology of nonspecific inflammation granuloma. Cortico-steoid therapy is effective after the definitude of the disease. (Chin J Ocul Fundus Dis, 2006,22:385-386)
Objective To investigate the retinal toxicity and verify the safe dose of intravitreal injection of nonsteroid anti-inflamatory drug,diclofenac sodium.Methods Twenty-eight healthy adult white rabbits were divided at random into 7 groups and received in every right eye the intravitreal injection of a single dose of diclofenac sodium solution ranging from 0.4-0.1 mg/0.1ml respectively ,the left eyes were regarded as conreol ones.Before injection and on the 1st,3rd,7th,14th,21st,and 28th day after injection the electroretinography on both eyes was examined.On the 28th day after injection the retinas of two rabbits of every group were examined by using light microscopy.On the 10th and 30th day after injection the retinal tissues around the optic nerve sisk of two eyes from every group at random were tested by using transmission electron microscopy.Results The retio of amplitude ofb wave of electroretinography in 0.4mg and 0.5mg groups had no sighnificant difference from groups before injection,the retinal tissues showed no structural changes in light and ecectron microscopy examination.The ratio of amplitude ofb wave of photoptic electroretinogrphy in 0.6mg groups in the early stage after injection was markedly reduced（P＜0.05）and returned to that before injection with time,reversible change of the edematou retina was discovered.The ratio of amplitude of b wave of electroretinography in 0.7-1.0mg groups was distinctly descreaded after injection（P＜0.05 or P＜0.01）,the cells of all the retinal layer revealed apparent and irreversible damage.Conclusion The largest dose of safety of intravitreal diclofenac sodium should be not more than 0.6mg.The toxic effect of intravitreal diclofenac sodium on retina is concerned mostly to cones and rods.
Objective To observe the change of diffusion upper limit of macromol ecules through pathological retina and the difference between the layers of retina. Methods Retinal edema was emulated by establishing branch retinal vein occlusion (RVO) model in miniature pig eyes under photodynamic method. Two days later, the retinas of both eyeballs were peeled off. The diffusion test apparatus was designed by ourselves. FITC-dextrans of various molecular weights (4.4, 9.3, 19.6, 38.9, 71.2 and 150 kDa) and Carboxyfluorescein (376 Da) were dissolved in RPMI1640 solutions and diffused through inner or outer surface of retina. The rate of transretinal diffusion was determined with a spectrophotometer. Theoretical maximum size of molecule (MSM) was calculated by extrapolating the trend-linear relationship with the diffusion rate. In separate experiments to determine the sites of barrier to diffusion, FITC-dextrans were applied to either the inner or outer retinal surface, processed as frozen sections, and viewed with a fluores cence microscope. Results FITC-dextrans applying to inner retinal surface, 4.4 kDa dextrans were largely blocked by inner nuclear layer (INL); 19.6,71.2 kDa dextrans were blocked by the nerve fiber layer (NFL) and inner plexiform layer; 15.0 kDa dextrans were blocked by NFL. FITC-dextrans applying to outer retinal surface, most dextrans with various molecular weights were blocked before outer nuclear layer (ONL). No matter applying to the inner or outer surface, Carboxyfluore scein can diffuse through the whole retina and aggregate at INL and ONL. After RVO, the inner part of retina became edema and cystoid, loosing the barrier function. Compared with the normal retina, the MSM in RVO tissues increased (6.5plusmn;0 39nm Vs 6.18plusmn;0.54nm, t=4.143, P=0.0001). Conclusions A fter RVO, the barrier function of inner part of retinal is destroyed and the upper limit of diffusion macromolecule size increased, which is nevertheless limited. ONL acts as bottle-neck barriers to diffusion, if the outer part of retina is damaged, the change of the diffusion upper limit will be prominent. （Chin J Ocul Fundus Dis，2008，24：197-201）
Objective To observe the effect of resveratrol on multidrug resistance (MDR) in human retinoblastoma cells treated. Methods RB cells in logarithmic growth phase were divided into experimental group and control group. RB cells in experimental group were cultured with different concentrations of resveratrol (6.25, 12.50, 25.00, 50.00, 100.00 mu;mol/L) for 24 and 48 hours. The proliferation (absorbance value) was assayed using methyl thiazolyl tetrazolium (MTT). RB cells were cultured with 50.00 mu;mol/L resveratrol for 48 hours. The expressions of MDR-1, cyclooxygenase-2 (COX-2)、multidrug resistance-associated protein-1 (MRP-1), glutathione-S-transferases-pi; (GST-pi;) were determined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. The RB cells of the control group were cultured with 0.5% dimethyl sulfoxide. Results Compared with the control group, the absorbance value decreased in experimental groups (6.25, 12.50, 25.00, 50.00 mu;mol/L) in a dose dependent manner (F=4.782，P＜0.05). The difference of absorbance value between 50.00 and 100.00 mu;mol/L experimental groups was not significant (F=6.351,P＞0.05). Compared with the control group, the mRNA (t=9.170, 5.758, 4.152, 4.638) and protein (t=3.848, 5.955, 4.541, 3.514) expression levels of MDR-1, MRP1, COX-2, and GST-pi; decreased in the experimental group (P＜0.05). Conclusion Resveratrol can down-regulate the expression of MDR in RB cells.