Objective
To investigate the effect of hepatocyte growth factor (HGF) on the barrier function of retinal peigment epithelium (RPE) and to detect the pathological mechanism of retinal detachment (RD) induced by over expression of HGF in RPE.
Methods
Sub-retina injection of E1/E3deleted adenoviral vectors encoding HGF (Ad CMV.HGF) and green fluorescent protein (Ad CMV.GFP) in adult pigmented rabbits [5times;104 plaque-forming units (pfu)/eye] to set up the model of retinal detachment. The ocular fundus and pathological changes were observed 3, 7, 14, and 28 days after injection. The expression level of HGF in retina and vitreous body was detected by immunohistochemistry and enzyme linked immunosorbent assay (ELISA).
Results
In the control eyes injected with AdCMV.GFP, expression of GFP only detected in RPE monolayer. The eyes injected with AdCMV.HGF had b HGF immune positive action in RPE cells at the injection site. The expression level of HGF in vitreous body reached the peak 7 days after injection and decreased to the basic level 28 days after injection. Chronic RD and chronic choroidal inflammation were found in the eyes injected with AdCMV.HGF within the time frame of HGF expression. Proliferative RPE cells were found in subretinal space in the region of RD, and multilayered cellular membranes developed in some eyes.
Conclusion
Over expression of HGF in RPE may induce chronic serous RD with subretinal proliferation of RPE, which suggests that HGF should be further studied as a target for therapeutic intervention in RD.
(Chin J Ocul Fundus Dis, 2007, 23: 193-197)
Objective To observe the clinical efficacy of external-route microsurgery for retinal detachment (RD). Methods In 36 patients (36 eyes) with single rhegmatogenous RD, the silica gel piece and/or buckling bands were preplaced, and drainage of subretinal fluid, retinal cryotherapy, e xamination of locating the holes, and intraocular injection of gas were performe d under surgical microscope. The surgical effects were compared with those of ot her simultaneous 37 patients with rhegmatogenous RD who underwent surgery under binocular indirect ophthalmscope. Results The simultaneous intraoperative observation of the fundus details and the sclera through the microscope was excellent in all cases. Under the surgical microscope, the reaction of r etinal cryotherapy was clearly visible without any serious surgical sequela. The observation of reaction of retinal cryotherapy and the orientation of the holes were not affected by mild opacity of the refractive media. Retinal reattachment was achieved in 31 eyes after the primary surgery and in 3 eyes after the secon dary surgery, with the final rate of rettachment of 94%. The best-corrected vi sual acuity was ＜0.1 in 6 eyes (16.7%), 0.1-0.4 in 15 eyes (41.7%), and ≥ 0.5 in 15 eyes(41.7%). The results were similar to those of the patients underwent surgery under indirect ophthalmoscope.Conclusion The external route microsurgery is simple, convenient, reliable, and effective. (Chin J Ocul Fundus Dis，2004，20：369-373)
The activities and distributions of succinate dehydrogenase(SDH),malic dehydrogenase(MDH),lactic dehydrogenase(LDH),acid phosphatase(ACP) and alkaline phosphatase(AKP) in retinal vessels were studied and observed with enzymatic histochemical techniques. The retinal vessels showed a b LDH activity, moderate SDH and MDH activity. The dehydrogenase activity described above was evenly and equally distributed in the microvasculature between arterioles and venules, and was the best in arteries. AKP showed predominant activity in the endothelial cells of capillaries and arterioles which were stained bly. No activity for ACP observed in the retinal vessels. The observations above indicate that the retinal vessels are metabolically active and have a great capacity for glycolysis.
（Chin J Ocul Fundus Dis,1992,8:6-9）
Objective To analyze the molecular composition of type IV collagenous fibres in internal limiting membrane (ILM) of human retina. Methods ILM was surgically removed from retina and identified under phase-contrast and transmission electron microscopes. Monoclonal antibodies against different αchains (α1-α6) of type IV collagen were immuno-localized. Results α3, α4, and α5 chains of type IV collagen were immuno-localized in human retinal ILM, while α1, α2, and α6 chains could not be immuno-localized. Conclusion Type IV collagenous fibres in human retinal ILM are composed of α3, α4, and α5chains. (Chin J Ocul Fundus Dis，2004，20：364-368)
ObjectiveTo observe the clinical features of retinal arterial occlusion (RAO) in youth.MethodsThis is a retrospective case review. Nine patients (9 eyes) with RAO were enrolled in this study. There were 6 males (6 eyes) and 3 females (3 eyes). The average age was (14.22±3.93) years. The best-corrected visual acuity (BCVA), indirect ophthalmoscopy, fundus color photography and fundus fluorescein angiography were performed. All patients underwent systemic evaluation including blood routine, erythrocyte sedimentation rate, blood lipids, vasculitis screening, homocysteine level, antiphospholipid antibody, blood coagulation, neck vascular ultrasound, and cardiac color ultrasound and electrocardiogram examination. All patients received oxygen therapy, blood medications and symptomatic treatment. Meanwhile, the patients with autoimmune diseases were received systemic glucocorticoid therapy. The follow-up was ranged from 6 to 12 months. The visual acuity and fundus change before and after treatment were compared.Resultsamong 9 patients, one patient had systemic lupus erythematosus, one patient had congenital heart disease, one patient had hypergammaglobulinemia, and carotid artery color ultrasonography showed that the internal carotid artery vessels faltered in 2 cases. The BCVA was 0.01 - 0.12. Among 9 eyes, there were 5 eyes (55.6%) with retinal branch artery occlusion (BRAO), 2 eyes (22.2%) with central retinal artery occlusion (CRAO), 2 eyes (22.2%) with ciliary retinal artery occlusion (CLAO). CRAO eyes showed positive RAPD (relative afferent pupillary defect), fine retinal artery and the corresponding vein, pale white retinal edema in posterior area and macular cherry-red spot. BRAO eyes manifested as inferior temporal artery occlusion and pale white retinal edema around them. CLAO eyes showed temporal ligulate grey-white retinal edema. At the last follow-up, BCVA improved and retinal vessels returned to normal in 7 eyes (77.8%); BCVA unchanged and no improvement in fundus in 2 eyes (22.2%).ConclusionAdolescent RAO is mostly partial occlusion, the prognosis is generally good after early active treatment.
Purpose
To study the effects of Schwann cells(SC) on promoting and supporting axon growth of rabbit retinal neurons in vitro.
Methods
The scistic nerves of neonatal rabbits were dissected and cultured for 2 weeks to obtain SC monolayers. The retinal cells that had been freshly dispersed were seeded respectively onto the SC monolayers or poly L lysine covered dishes,and the morphology of cultured retinal neurons was observed and the 24th hours and 48th hours respectively under the phase contrast microscopic.
Results
Retinal neurons of neonatal rabbits attached to the two substrate and extended axons at the 24th hour.Neurite length on SC reached 85plusmn;17mu;m at the 24th hour and 283plusmn;27mu;m at the 48th hour respectively and was significantly longer than on acellular substrate (Plt;0.01)
Conciusion
SCs are effctive in promoting and supporting neurite growth of retinal neurons in vitro.
(Chin J Ocul Fundus Dis,1998,14:212-214)
ObjectiveTo investigate the therapeutic effects of scleral buckling operations on treating longstanding retinal detachment with subretinal proliferation.MethodsThe clinical data of 36 patients (40 eyes) with long-standing retinal detachment with subretinal proliferation who had undergone scleral buckling operation were retrospectively analyzed, and the clinical features, therapeutic methods and curative effects were summarized.ResultsThe diagnosis of long-standing retinal detachment mainly based on the examination of ocular fundus. The features of the affected eyes were: flat retinal detachment, thin and transparent retina, and formation of subretinal cords. In 40 eyes undergone scleral encircling and buclking, 36 (90%) had one-off successful operation, and the visual acuities over 0.05 were found in 77.5% of the whole eyes.ConclusionsScleral encircling and buckling procedures can be used to treat long-standing retinal detachment with subretinal proliferation with fairish cured rate. (Chin J Ocul Fundus Dis, 2005,21:150-152)
Objective:To study combination effects of gamma;-ray radiation and hyperthermia on the in vitro cell proliferation of cultured human retianl glial cells in order to explore possible application of the combination treatment for proliferative vitreoretinopathy.
Methods:Cultured human retinal glial cells were tread by radiation, hyperthermia,or a combination of the two.Cell proliferation was evaluated by MTT method.
Results:gamma;-ary irradiation of 100cGy or 300cGy was not effective in suppressing proliferation of the retinal glial cells,neither was the heat treatment at 42℃ or 43℃ for 30 min.Howver,combination of hyperthermia at 42℃ for 30min with 300cGy irradiation suppressed cellular growth of the retinal glial cells to 25.2% of the control.Combination treatment of 43℃，30 min hyperthermia and 300cGy irradiation was more effective.
Conclusion:A combination of low dose radiation and mild hyperthermia is effective in the suppression of frowth of cultured human glial cells,and the effects were found to be synergistic.It is expected that the synergistic effects will lower the radiation dose and and also reduce the possible side effects of radiation in the treatment of proliferative vitroretinopathy.
(Chin J Ocul Fundus Dis,1998,14:29-32)
Objective
To evaluate the variability of four parameters of multi-focal electroretinogram (mERG) a-wave amplitude, b-wave amplitude, awave latent period, b-wave latent period.
Methods
Sixty normal eyes of 46 volunteers were divided into 3 groups of different ages. RETIscan 3-12 system was used to carry out mERG examination. The stimulus matrix of 61 hexagonal elements spanning the central 24deg;of the visual field. These hexons were scaled with eccentricity and divide d into 5 rings. First-order kernel was selected.
Results
The variability of four parameters of mERG was great. The variability of b-wave latent period was the smallest, its coefficient of variatian was 4.52%～15.62%；that of a-wave latent period held the second place:10.29%~48.67%；that of b-wave amplitude was greater:25.92%~76.11%；that of a-wave amplitude was the greatest:43.82%~88.23%. The results of three groups showed that b-wave amplitude of ring 1 had the smallest variability.
Conclusions
The variability of latent period is smaller than that of amplitude; the variability of b-wave was smaller than that of a-wave. The longer the centrifugal distance, the lower the amplitude density of a-wave and b-wave. Physiological and anatomical factors might be important for the variability of parameters of multi-focal electroretinogram.
(Chin J Ocul Fundus Dis, 2001,17:277-279)
Purpose
To investigate the development of embryonic stem cells (ESC)in the subretinal space．
Methods
ESC were cultivated in suspension for 4 days till they developed into cell aggregates,i.e.embryonic body(EB).ESC as well as EB combined with or without RA were respectively transplanted into vitreous cavity and subretina1 space in SD rats,and the subretinal transplanted eyes,transient ischemia-reperfusion injuries were made by ligating the ophthalmic artery for 40 seconds before the transplantation .The experimental eyes were enucleated for histological and immunohistochemical assays after 14～28 d.
Results
The EB was found to develope into photoreceptors induced by RA in the subretinal space under an ischemia-reperfusion condition，and EB transplantation without RA induction induced multiple differentiations in the subretinal space.The single injection of RA without EB induced hyperplasia of the neural retinal cells.ESC transplanted into vitreous cavity rapidly proliferated and developed into atypical hyperplastic mass.
Conclusion
EB derived from ESC can differentiate into photoreceptors induced by RA in the host subretinal space under an ischemia-reperfusion condition.
(Chin J Ocul Fundus Dis，2000，16：213-284)
