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<p><b>BACKGROUND</b>The mechanisms of pathological retinal neovascularization (RNV) remain unknown. Several microRNAs were reported to be involved in the process of RNV. Oxygen-induced retinopathy (OIR) is a useful model to investigate RNV. Our present work explored the expression and the role of microRNA-128 (miR-218) in oxygen-induced RNV.</p><p><b>METHODS</b>OIR was used to establish RNV model. The expression level of miR-218 in the retina from OIR mice was assessed by quantitative real-time reverse transcriptase polymerase chain reaction. Fluorescein angiography was performed in retinae of OIR mice, and RNV was quantified by hematoxylin and eosin staining to evaluate the effect of pCDH-CMV-miR-218 intravitreal injection on RNV in OIR mice. Roundabout 1 (Robo1) expression was detected by Western blotting in mouse retinal vascular endothelial cells expressing a high or low level of miR-218 and retinal tissues from OIR mice. Cell migration was evaluated by scratch wound assay.</p><p><b>RESULTS</b>In OIR mice, the expression level of miR-218 was significantly down-regulated (P = 0.006). Retinal Robo1 expression was significantly increased at both mRNA and protein levels (P = 0.001, 0.008; respectively). miR-218 intravitreal injection inhibited retinal angiogenesis in OIR mice, and the restoration of miR-218 in retina led to down-regulation of Robo1.</p><p><b>CONCLUSIONS</b>Our experiments showed that restoration of miR-218 inhibited retinal angiogenesis via targeting Robo1. MiR-218 contributed to the inhibition of retinal angiogenesis and miR-218 might be a new therapeutic target for preventing RNV.</p>
Subject(s)
Animals , Mice , Cell Movement , Cells, Cultured , Mice, Inbred C57BL , MicroRNAs , Physiology , Nerve Tissue Proteins , Physiology , Oxygen , Pharmacology , Receptors, Immunologic , Physiology , Retinal NeovascularizationABSTRACT
To investigate risk factors and efficacy of reoperation for neovascular glaucoma ( NVG) secondary to vitrectomy in proliferative diabetic retinopathy (PDR). ●METHODS:Seven cases (7 eyes) from October, 2009 to December, 2012 were analyzed retrospectively. All the patients had NVG after the primary vitrectomy for PDR and were performed secondary vitrectomy combined with laser photocoagulation . ●RESULTS: The mean intraocular pressure ( lOP) was (11. 21±4. 22)mmHg before primary surgery. The number of laser spots ranged from 622 to 1124 during the first vitrectomy. Cataract extraction was performed in all 7 cases and intraocular lens was implanted in 5 cases. The mean lOP was (10. 11± 3. 62) mmHg during 2mo after the primary surgery. During follow- up, all the patients had significantly progressive intraocular inflammation. Vitreous hemorrhage was not absorbed completely in 2 cases and recurrent vitreous hemorrhage occurred in the other 5 cases. Five cases had poor glycemic control and the other 2 cases had bad blood pressure control. NVG occurred in all 7cases. The mean lOP was (41. 13 ± 7. 76) mmHg before the secondary surgery. After the secondary surgery, the lOP were under control in 5 cases. For the other 2 cases, the lOP was controlled in one case by transscleral cyclophotocoagulation, another one was lost in follow-up with uncontrolled lOP. ●CONCLUSlON: Primary vitrectomy combined with lens extraction, insufficient laser speckle, unabsorbed and recurrent vitreous hemorrhage, intraocular inflammation and systemic condition may be the risk factors associated with the occurrent of NVG after vitrectomy in PDR. Secondary vitrectomy combined with sufficient retinal photocoagulation is efficiency for NVG after vitrectomy for the PDR.
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BackgroundSeveral cornea collagen crosslinking methods have been used to treat keratoconus.However,the safety of these methods is dissatisfactory.Glyceraldehyde is a very potent and highly reactive crosslinking agent,with little toxicity,but its effect on corneal biomechanical property is poorly clear.ObjectiveThe aim of this study was to evaluate the biomechanical effects of glyceraldehyde collagen crosslinking on rats cornea.Methods Fifteen clean SD rats were randomly divided into 0.005 mol/L glyceraldhyde group,0.050 mol/L glyceraldhyde group and blank control group.Glyceraldhyde drops was topically administered in the right ryes 2 times per day for consecutive 7 days in the 0.005 mol/L and 0.050 mol/L glyceraldhyde groups,and no any eye drops was used in the blank control group.Seven days later,the rats were sacrificed.Transparency of corneal buttons in these different groups was evaluated.The central corneal strips of 2 mm×6 mm with 2 mm scleral tiasue were obtained for the biomeehanical stress-strain measurement,including ultimate stress ( MPa),ultimate strain (％) and 6％ elastic modulus (MPa).Corneal collagen fibril density was assessed by histological examination under a light microscopy.The use of the animals followed the Regulations for the Administration of Affair Concerning Experimental Animals by State Science and Technology Commission.ResultsThe words could be clearly displayed transcorneally in all the three groups.When strain was 6％,the stress was (0.463±0.065 ) MPa in 0.005 mol/L glyceraldehyde group,(0.846±0.240) MPa in 0.050 mol/L glyceraldehyde group,both showing a significant increase in comparison with (0.195±0.103 ) MPa of the blank control group (P=0.029,0.000 ).Following the crosslinking treatment,the ultimate stress was significant elevated in 0.050 mol/L glyceraldehydes group compared with the blank control group ( ( 10.759 ± 3.337 ) MPa vs.(5.295± 1.313 ) MPa,P =0.007 ),but no significant change between the 0.005 mol/L glyceraldehydes group and the blank control group ( ( 6.043 ±2.084) M Pa vs.(5.295 ± 1.313 ) MPa,P =0.660 ).Corneal ultimate strain was lower in the 0.005 mol/L glyceraldehyde group and 0.050 mol/L glyceraldehyde group than the blank control group (36.57％ ±3.09％ vs.43.87％ ± 1.89％,P =0.009;28.53％ ±1.89％ vs.43.87％ ± 1.89％,P =0.000).However,significantly increased 6％ elastic modulus were seen in the 0.005 mol/L glyceraldehyde group and 0.050 moL/L glyceraldehyde group compared with the blank control group ( ( 7.718 ± 1.076 ) MPa,( 14.102 ± 4.011 ) MPa vs.( 3.252 ± 1.717 ) M Pa),with statistically significant differences ( P =0.029,0.000).Histological examination showed a increase of collagen fiber density in the 0.050 mol/L glyceraldehyde group.Conclusions Corneal collagen crosslinking induced by glyceraldehyde strengthens biomechanical intensity and increases the density of corneal collagen fiber.But the safety of glyceraldehyde crosslinking for keratoconus needs further study.
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Background The development of retinopathy of prematurity(ROP) is associated with many regulatory cytokines related to neovascularization;however,the retinal expression and regulated mechanism of stromal cell-derived factor-1 (SDF-1) in mouse model of oxygen-induced retinopathy (OIR) remain uncertain.Objective This study was to investigate the expression of SDF-1 in retina of mouse model of OIR.Methods Forty 7-day-old C57BL/6J mice were divided into OIR group and control group.In OIR group,20 mice were exposed to 75% oxygen for 5 days and then to room air for 5 days.In control group,20 mice were raised in room air.The expression of SDF-1 in retina of mice was studied by immunochemistry and quantified by real time reverse transcriptase polymerase chain reaction (RT-PCR).Results The positive immunohistochemical staining for SDF-1 was found mainly locating at the ganglion cell layer in 12-day-old mice of OIR group;the stronger positive immunohistochemical staining for SDF-1 was noted mainly locating at the ganglion cell layer,vascular endothelial cells of inner retina,neovascular endothelial cells in 17-day-old mice of OIR group;the delicate positive immunohistochemical staining for SDF-1 was both found mainly locating at the inner retina and being around the retinal vascular in 12-day-old mice of control group and 17-day-old mice of control group.The expression of SDF-1 mRNA in 17-day-old mice of OIR group was higher than that of 12-day-old mice of OIR group (t=8.072,P＜0.05)and 17-day-old mice of control group(t=10.026,P＜0.05),respectively.The expression of SDF-1 mRNA in 12-day-old mice of OIR group was lower than that of 12-day-old mice of control group (t=4.336,P＜0.05).Conclusion SDF-1 might improve the onset of retinal neovascularization of OIR.
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To describe a modified simple iris suture for pupillary dilation technique during vitrectomy in cases with a miotic pupil.Four translimbal incisions were created with a sharp straight blade at 1:30,10:30,4:30,and 7:30 o'clock,respectively.The straight needle of 10-0 polypropylene suture and a Sinskey IOL hook was used to displace the pupillary margin toward the limbus.In 3 cases,four sutures caused a 6-mm to 9-mm square-shaped pupil,and the pupil was allowed to return to a smaller size at the end of the operation.It is simple and may reduce postoperative complications.
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<p><b>OBJECTIVE</b>To observe the experimental results and histopathological changes of acellular xenogenic dermal matrix (X-ADM) and allogeneic sclera used as wrapping materials of hydroxy apatite (HA) ocular implants in New Zealand white rabbits.</p><p><b>METHODS</b>Twenty-four rabbits received unilateral eye enucleating and the sockets were implanted with HA spherical implants wrapped with either acellular xenogenic dermal matrix or allogeneic sclera at random. The rabbits were examined for inflammation and implant exposure and sacrificed at 1, 2, 4, 6, 8 and 12 weeks after implantation. The sockets with the grafts were exenterated and the specimens were assessed histopathologically and ultrastructurally with light or transmission electron microscopy for the changes in inflammation reaction and vascularization.</p><p><b>RESULTS</b>Compared to allogeneic sclera at the same stage of implantation, acellular xenogenic dermal matrix demonstrated more active and earlier growth of fibroblasts and new vessels with abundant collagen deposition. There were few inflammatory cells and no rejection was found.</p><p><b>CONCLUSION</b>This experiment showed that the acellular xenogenic dermal matrix, with fast neovascularization and low immunity, can be an ideal material of ocular implant and a good substitute for allogeneic sclera.</p>
Subject(s)
Animals , Female , Male , Rabbits , Dermis , Transplantation , Eye, Artificial , Hydroxyapatites , Sclera , Transplantation , Swine , Transplantation, Heterologous , Transplantation, HomologousABSTRACT
@#ObjectiveTo observe clinical results and histopathological changes of scleral defect repaired with acellular xenogenic dermal matrix (Xeno-ADM) in rabbits.MethodsModel of rabbit sclera defect was established, and repaired with Xeno-ADM. The rabbits were clinically examined for inflammation and eyeball healing. The animals were sacrificed at 2nd and 4th week after operation, and implants were obtained and examined histopathologyically and ultrastructully with light microscopies respectively to evaluating changes of inflammation and vascularization.ResultsThere were no obvious inflammation and eyeball deformation observed. 2 weeks after implantation, the partial inflammatory cell invasion was seen with the light microscopy, and there was an obvious borderline between the Xeno-ADM and the sclera. 4 weeks after implantation, the inflammatory cells were reduced noticeably, the Xeno-ADM and the sclera completely merged with each other.ConclusionThe acellular xenogenic dermal matrix may be an ideal materix with fast neovascularization and low immunity for replace of sclera implants.