ObjectiveTo investigate the impact of L-Phenylalanine on the efficiency of retinal pigment epithelial (RPE) cell derivation from human embryonic stem cells (hESCs) and explore the underlying mechanisms. MethodsH1 hESCs were routinely cultured with mTeSR medium and divided into control and experimental groups. When cells reached over-confluence, spontaneous differentiation was triggered using 10% KSR differentiation medium without bFGF. L-Phenylalanine (0.2 mmol/L) was supplemented in the experimental group from the 3rd week. The expression of RPE markers and Wnt signaling components in the two groups was detected by Real time-RCR, Western blot and Flow cytometry analyses. Purified hESC-RPE cells and PBS were injected into the subretinal space of sodium iodine-induced retinal degeneration rats separately. Retinal function was assessed by ERG 6 weeks after the transplantation. ResultsOn the 7th week, much more pigment cell clumps appeared in the experimental group compared to the control group. Within these areas there were monolayer hexagonal RPE cells full of pigment granules. The experimental group showed significantly higher expression of Pax6, MITF, Tyrosinase, RPE65, Wnt3a, Lef1 and Tcf7 genes than the control group (P < 0.01). Higher expression level of MITF and RPE65 proteins and higher percentage of RPE65 (+) cells (P < 0.01) were detected in the experimental group. 6 weeks after sub-retinal transplantation of hESC-RPE cells, the amplitudes of a-b wave in the transplanted eyes were significantly higher than those in the control eyes (P < 0.01) at the stimulus intensity of 3.0 cd·s/m2. ConclusionsL-Phenylalanine effectively promoted the differentiation of embryonic stem cells into retinal pigment epithelial cells, and its impacts on the Wnt/β-catenin signaling pathway may partially explain the underlying mechanisms. Subretinal transplantation of hESC-RPE remarkably improved the retinal functions of retinal degenerative animal models.
Objective：To observe the protective effect of ginkgo bilo ba extrac t (EGb 761), a free radical scavenger, on the photoreceptor cells after lighti nduced retinal damage. Methods：Seventytwo female SpragueDa wley (SD) rats we re randomly divided into 4 groups: normal control group, lightinduced retinal da m age model group, model+physiological saline group, and model+EGb 761 group, with 18 rats in each group. All of the rats except the ones in the control group were exposed to white light at (2740plusmn;120) lx for 6 hours after the dark adap tation for 24 hours to set up the lightinduced retinal damage model. Rats in m o del + physiological saline group and model+EGb 761 group were intraperitoneall y injected daily with physiological saline and 0.35% EGb 761 (100 mg/kg), respec tively 7 days before and 14 days after the light exposure. Apoptosis of photorec eptor cells was detected 4 days after light exposure; 7 and 14 days after light exposure, histopathological examination was performed and the layer number of ou ter nuclear layers (ONL) on the superior and inferior retina was counted. Results：Four days after light exposure, the apoptosis of photorecep tor cells was fou nd on ONL in model, model+ physiological saline and model+EGb 761 group, and w as obviously less in model + EGb 761 group than in model and model+physiologic al saline group. Seven days after light exposure, the layers of ONL on the super ior retina were 3 to 4 in model and model+physiological saline group, and 7 to 8 in model+EGb 761 group; the mean of the layer number of ONL in model+EGb 761 group (6.92plusmn;0.82) was less than that in normal control group (8.40plusmn;0.95) (t=-1.416, P＜0.05), but significantly more than that in model (5.96 plusmn;1.36 ) and model+physiological saline group (5.90plusmn;1.40）（t=1.024, 1.084; P＜0.05). Fourteen days after light exposure, the layers of ONL on the superior retina were 0 to 1 in model and model+physiological saline group, and 3 to 4 i n model+EGb 761 group. The mean of the layer number of ONL in model+EGb 761 group (5.5 2plusmn;1.06) was significantly more than that in model (3.44plusmn;2.15) and model + physiological saline group (3.37plusmn;1.91) (t=2.082, 2.146, P＜0.05). Conclusion：EGb 761 can partially inhibit the apoptosis of pho toreceptor cells, thus exert protective effect on photoreceptor cells.
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 observe the visual field loss after 577 nm krypton pan-retinal photocoagulation (PRP) in the treatment of diabetic retinopathy (DR). Methods A prospective clinical studies. Forty-six eyes of 26 patients with proliferative DR (PDR) and severe non-proliferative DR (NPDR) diagnosed by clinical examination from No. 306 Hospital of PLA during January 2014 and December 2015 were included in this study. Among them, 21 eyes of NPDR and 20 eyes of PDR; 13 eyes with diabetic macular edema (DME) (DME group) and 28 eyes without DME (non-DME group). All eyes underwent best corrected visual acuity (BCVA), fundus color photography, fundus fluorescein angiography (FFA) and optical coherence tomography (SD-OCT) examinations. The visual field index (VFI) and visual field mean defect (MD) values were recorded by Humphrey-7401 automatic visual field examination (center 30° visual field). The BCVA of DR eyes was 0.81±0.28; the VFI and MD values were (89.8±8.4)% and −7.5±3.85 dB, respectively. The BCVA of the eyes in the without DME group and DME group were 0.92±0.20 and 0.57±0.27, the VFI were (90.86±7.86)% and (87.46±9.41)%, the MD values were −6.86±3.43 and 8.87±4.48 dB. PRP was performed on eyes using 577 nm krypton laser. The changes of VFI, MD and BCVA were observed at 1, 3, and 6 months after treatment. Results Compared with before treatment, the VFI of DR eyes decreased by 12.0%, 12.3% and 14.8% (t=7.423, 4.549, 4.79; P＜0.001); the MD values were increased by −4.55, −4.75, 6.07 dB (t=−8.221, −5.313, −5.383; P＜0.001) at 1, 3 and 6 months after treatment, the differences were statistically significant. There was no difference on VFI (t=1.090, −0.486; P＞0.05) and MD value (t=−0.560, −0.337; P＞0.05) at different time points after treatment. Compared with before treatment, the BCVA was significantly decreased in DR eyes at 1 month after treatment, the difference was statistically significant (t=2.871, P＜0.05). Before and after treatment, the BCVA of the DME group was lower than that of the non-DME group, the difference were statistically significant (t=4.560, 2.848, 3.608, 5.694; P＜0.001); but there was no differences on the VFI (t=1.209, 0.449, 0.922, 0.271; P＞0.05) and MD values (t=1.582, 0.776, 0.927, 1.098; P＞0.05) between the two groups. Conclusion The range of 30° visual field loss is about 12%-14.8% after 577 nm krypton laser PRP for DR. VFI and MD can quantitatively analyze the and extent of visual field loss after PRP treatment.
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）
目的 针对近期收治的1例常规治疗疗效不理想的溃疡性结肠炎患者,我们进行了证据检索和评价,以期找到更有效的治疗方法.方法 计算机检索MEDLINE(1978～2004)、CBMdisc(1978～2004)及Cochrane图书馆(2004年第3期),查找 5-氨基水杨酸(5-ASA)灌肠液治疗溃疡性结肠炎及与病情缓解有关的系统评价、临床随机对照试验等,并对所获证据进行评价.结果 高质量的临床证据表明,5-ASA灌肠液治疗溃疡性结肠炎及帮助病情缓解均优于口服5-ASA及柳氮磺胺嘧啶局部灌肠治疗.据此临床证据,结合医生经验及病人意愿,对该例患者实施5-ASA 1g+生理盐水100 ml qd,睡前保留灌肠治疗.1周后,患者临床症状明显缓解,腹泻基本停止,每天解黄色黏液便1～2次.肠镜复查,炎症较前明显减轻.出院后继续用上述方案维持治疗,每周2次.门诊随访1年,患者未再复发,也无明显副作用发生.结论 5-ASA灌肠液是控制溃疡性结肠炎活动期间病情及帮助缓解、减少复发的有效药物.
Objective To observe the effect of vitrectomy (PPV) combined with silicone oil filling on the stability of the tear film. Methods A total of 72 eyes of 36 patients with vitreous hemorrhage and retinal detachment were enrolled in the study with PPV combined with silicone oil filling. The operation and contralateral eyes were set up in the operation group and the control group respectively, each had 36 eyes. The tear film rupture time (BUT), the base tear secretion test or Schirmer Ⅰ test (SⅠT) and corneal fluorescein staining (CFS) were performed at 7, 30, 60, and 90 days after operation. The difference of BUT, SⅠT and CFS at different time points after the operation of the two groups were compared. Results After operation 7, 30 days, SⅠT and CFS increased, BUT staining is shortened in the surgery group, the differences were statistically significant (t=1.78, P＜0.05); after operation 60, 90 days, SⅠT, CFS, BUT were same between the surgery group and the contralateral eyes (t=12.39, P＞0.05). Conclusion PPV combined with silicone oil filling can affect the stability of the tear film, which can be recovered to the preoperative level at postoperative 60 days.
Objective To investigate the refractive changes of ocular measurable factors due to scleral buckling surgery. Methods A total of 86 eyes of successful rhegmatogenous retinal detachment with a higher encircling scleral buckle underwent A-scan and keratometer examination before surgery as well as l week,4 and 12 weeks after surgery.The refractive factors included the depth of anterior chamber,thickness of lens,axial length of eye,corneal curvature and refraction of eye were detected pre- and post-operatively. Results Compared with preoperation,the depth of anterior chamber was decreased significantly at the lst,4th and 12th postoperative week(P＜0.05),while no significant change of the axial length of eye was observed.The thickness of lens was increased significantly and the refractive error was myopic shifted at the lst and 4th week after operation(P＜0.05),but no significant change was observed at the 12th postoperative week.Statistically significant difference was also observed in corneal curvature of central axis in the local bucklele;1 quadrant with encircling group between preoperation and the lst and 4th postoperative week. Conclusions With higher encircling scleral buckle,the refractive change after buckling surgery may be caused primarily by the shallowing of anterior chamber and thickening of lens. (Chin J Ocul Fundus Dis, 1999, 15: 227-229)
Objective To evaluate ocular surface changes following minimal vitreoretinal surgery in postmenopausal women patients with proliferative diabetic retinopathy (PDR). Methods Sixty-one women PDR patients (61 eyes) underwent vitreous microsurgery were recruited in this prospective study, including 31 postmenopausal women (PMW group) and 30 non-postmenopausal women (non-PMW group). The contralateral eyes were considered as the control group. Corneal fluorescein (FL) staining, tear break-up time (TBUT), Schirmer I test (SIT), central corneal sensitivity and ocular surface disease index (OSDI) were estimated. All tests were carried out 1 day preoperatively and 1 day, 10 days, 1 month and 3 months postoperatively. The student’st test or Mann-WhitneyU and ANOVA for repeat measurements test were used. Results Preoperatively, TBUT of surgery and non-surgery eyes in PMW were shorter than non-PMW (t=−2.115, −2.035;P＜0.05), but higher OSDI scores were found in PMW (t=2.482, 2.208;P＜0.05). TBUT reduction rate (Z=−2.771, −1.993;P＜0.05) and OSDI rising rate (Z=2.539, 2.157;P＜0.05) of surgery eyes in PMW were higher than non-PMW 1 day and 10 days postoperatively. The lower SIT of surgery eyes in PMW were observed at 1 day and 10 days (t=−2.403, −2.029;P＜0.05) after surgery. At 10 days after surgery, FL and OSDI scores of surgery eyes in non-PMW returned to preoperative level (Z=−0.447, −0.513;P＞0.05), but in PMW, the recovery process experienced 1 month (Z=−1.500, −0.853;P＞0.05). TBUT and SIT of surgery eyes in two groups both reached preoperative level at 1 month following surgery (Z=−0.715, −1.266, −1.531, −0.522;P＞0.05). Conclusions PMW with PDR had ocular surface dysfunction, which resulted in aggravated dry eye after minimal vitreoretinal surgery.