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Age-related macular degeneration (AMD) is a progressive neurodegeneration disease that causes photoreceptor demise and vision impairments. In AMD pathogenesis, the primary death of retinal neurons always leads to the activation of resident microglia. The migration of activated microglia to the ongoing retinal lesion and their morphological transformation from branching to ameboid-like are recognized as hallmarks of AMD pathogenesis. Activated microglia send signals to Müller cells and promote them to react correspondingly to damaging stimulus. Müller cells are a type of neuroglia cells that maintain the normal function of retinal neurons, modulating innate inflammatory responses, and stabilize retinal structure. Activated Müller cells can accelerate the progression of AMD by damaging neurons and blood vessels. Therefore, the crosstalk between microglia and Müller cells plays a homeostatic role in maintaining the retinal environment, and this interaction is complicatedly modulated. In particular, the mechanism of mutual regulation between the two glia populations is complex under pathological conditions. This paper reviews recent findings on the crosstalk between microglia and Müller glia during AMD pathology process, with special emphasis on its therapeutic potentials.

Chalcone is a plant metabolite widely found in fruits, vegetables, spices and tea, and has anti-tumor, anti-inflammation, immunomodulation, antibacterial and anti-oxidation activities, as well as many other pharmacological and biological effects. Our team has shown that its analogs have antioxidant activity, and oxidative stress is a pathological hallmark of retinal ischemia/reperfusion injury that can lead to retinal damage and visual loss. This investigation aims to identify a chalcone that protects retinal ganglion cells in vitro from the effects of oxidative stress and examine its mechanism. Rat retinal ganglion cell-5 cells were pretreated with chalcones and then exposed to tert-butyl hydroperoxide that causes oxidative damage. Controls received dimethyl sulfoxide only or tert-butyl hydroperoxide in dimethyl sulfoxide. Only (E)-3,4-dihydroxy-2'-methylether ketone (L2H17), of the five chalcone analogs, markedly increased the survival rate of oxidatively injured RGC-5 cells. Thus, subsequent experiments only analyzed the results of the L2H17 intervention. Cell viability and apoptosis were measured. Intracellular superoxide dismutase and reactive oxygen species levels were used to assess induced oxidative stress. The mechanism of action by L2H17 was explored by measuring the ER stress/UPR pathway and the expression and localization of Nrf2. All results demonstrated that L2H17 could reduce the apoptosis of oxidatively injured cells, inhibit caspase-3 activity, increase Bcl-2 expression, decrease Bad expression, increase the activity of superoxide dismutase, inhibit the production of reactive oxygen species, increase Nrf2 immunoreactivity, and reduce the activating transcription factor 4, phospho-eukaryotic initiation factor 2 and CHOP expression. L2H17 protects retinal ganglion cells induced by oxidative stress by regulating Nrf2, which indicates that it has the potential to become a drug for retinal ischemia/reperfusion., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest

Aim: To report a simple approach to actively remove high viscosity silicone oil through a 23-gauge cannula via pars plana., Methods: Forty-eight eyes of 48 patients underwent silicone oil (5700 centistokes) removal (SOR) were enrolled. A section of blood transfusion set was prepared to connect a standard 23-gauge cannula and vitrectomy machine. Silicone oil was removed with suction of 500-mm Hg vacuum through the cannula. Main outcome measures were SOR duration, number of sutured sites, intraocular pressure (IOP), best-corrected visual acuity (BCVA), and complications., Results: Silicone oil was successfully removed in all cases. The mean SOR time was 5.70±0.85min. Nine eyes (18.75%) needed suture partial sclerotomies. No intraoperative complications were noted. Transient hypotony (≤8 mm Hg) was seen in 3 eyes (6.25%) on postoperative day 1, but all resolved within 1wk. Retinal reattachment was achieved in all cases and no other postoperative complications were noted during 3-month following-up. BCVA at the final visit improved or stabilized in all patients comparing to the preoperative level., Conclusion: Active removal of high viscosity silicone oil through a 23-gauge instrument cannula jointed with blood transfusion set is a practical and reliable technique when considering two sides of efficacy and safety.

Aim: To determine the effects of epidermal growth factor (EGF) on the proliferation and migration of Müller cell line Moorfields/Institute of Ophthalmology-Müller 1 (MIO-M1), and its related molecular mechanisms under normal and oxidative stress conditions., Methods: Müller cells were cultured with different concentrations of EGF in the presence or absence of varied amounts of H2O2 and glucose oxidase (GO) which induced oxidative stress. The proliferation and migration of Müller cells were examined by 5-Bromo-2-deoxyUridine (BrdU), MTT assay, Transwell assay and scratch wound healing assays. The cell viability was determined with the MTT assay. The secretion of EGF by Müller cells was evaluated by ELISA. Western blot was performed to detect the activation of extracellular regulated protein kinases (ERK)1/2 and Akt signal pathways., Results: EGF stimulated the proliferation and migration of Müller cells in a concentration-dependent manner in vitro. Under oxidative damage condition, 2h of pretreatment with 10-100 ng/mL EGF can mostly inhibit 50% lethal dose of 0.08 mmol/L H2O2-induced cell damage. The Western blot results showed that after Müller cells were exposed to varying EGF for 24h, Akt and ERK1/2 were phosphorylated in a dose-dependent manner. In the presence of the LY294002, the potent PI3K inhibitor, the p-Akt was significantly attenuated., Conclusion: EGF may induce the proliferation and migration of human Müller cells through the Akt and the ERK1/2 signal pathways, and induce PI3K-mediated glioprotective effect under oxidative stress.

Objective: To evaluate the efficacy of vitrectomy without internal limiting membrane (ILM) peeling associated with gas tamponade in eyes with myopic foveoschisis., Methods: A prospective study was conducted, in which 49 pathological myopia patients (52 eyes) with myopic foveoschisis were enrolled and divided into three groups according to the different therapeutic procedures: 22 patients (24 eyes) underwent vitrectomy without internal limiting membrane (non-gas tamponade group), 15 patients (16 eyes) received vitrectomy without internal limiting membrane peeling but combined with gas tamponade (gas tamponade group) and 12 patients (12 eyes) did not receive surgical treatments (control group). SAS 9.13 was used for the statistic analysis. Best-corrected visual acuity (BCVA) and optical coherence tomographic (OCT) findings of the foveal thickness before and after the operation (the 3rd, 6th, and 9th month postoperatively) were obtained and compared by the Wilcoxon Rank-Sum test. Non-parameters Wilcoxon symbols test was used to compare the BCVA, the central foveal thickness (CFT) and maximum foveal thickness (MxFT) of each group before and after the surgery., Results: Postoperative visual acuity was significantly increased in the two operation groups (t = 2.57, P < 0.05; t = 3.58, P < 0.05) but not increased in the control group (t = 1.84; P > 0.05). The difference of BCVA between these three groups was not significant (χ(2) = 0.24, P > 0.05). OCT showed the mean foveal thickness was significantly decreased postoperatively. Vitrectomy without peeling of the ILM significantly promoted the retinal reattachment in eyes with myopic foveoschisis. No retinal reattachment was found in the control group while 16 and 13 retinal reattachment were found in the non-gas tamponade (66.7%) and gas tamponade group (81.3%), the difference between these two operation groups and the control was statistically significant (χ(2) = 20.50, P < 0.05). During the follow-up, two eyes in the control group developed a macular hole and both developed retinal detachment (RD) in the 6 and 8 month, respectively. The remaining 10 eyes did not develop any complications, although the thickness of the macula increased significantly. A transient increase of intraocular pressure occurred in three eyes and had been cured by medications within 2 weeks after gas tamponade. A macular hole was recognized in one eye 2 months after surgery and the retina was reattached at the fovea 1 month after reoperation., Conclusions: Vitrectomy without ILM peeling could be a safe and effective surgical approach for the treatment of foveoschisis in pathologic myopia. In addition, gas tamponade can improve the success rate of the operation.

Objective: To evaluate the prognosis of traumatic eyes with no light perception post vitrectomy, and to analyze the risk factors influencing the final results., Methods: Five hundred and ninety nine mechanically injured eyes in 577 patients undergone vitrectomy were registered from 1999 - 2004. Thirty-eight eyes in this group showed no light perception in initial visual examination. Thirty-two eyes (84.2%) had open-globe injury, the other 6 eyes (15.8%) had closed-globe injury. Excluded the enucleated eyes, the others were followed up for at least 6 months, averaged 7.2 months. All registered data were filled in predesigned forms. Each parameter was evaluated strictly according to the standards of the protocol. The risk factors of poor prognosis and traumatic no light perception were analyzed by logistic regression., Results: Fourteen eyes (36.8%) achieved anatomic and functional success. Three eyes (7.9%) attained anatomic success. Nine eyes (23.7%) were enucleated. Hypotony occurred in 4 eyes. Seven eyes were maintained by silicone oil. Atrophy of eyeball occurred in 1 eye. Twenty-one eyes (55.3%) achieved a final visual acuity of light perception or better, including: 0.2 in 3 eyes, 0.02 in 2 eyes, count finger in 3 eyes, hand move in 3 eyes, light perception in 10 eyes. Eight eyes (21.1%) remained no light perception. The logistic regression analysis identified the significant risk factors predictive of poor prognosis, including traumatic no light perception, presence of a relative afferent pupillary defect (RAPD), massive suprachoroid hemorrhage (MSCH), panretinal detachment with closed-funnel, ciliary body injury, preoperative atrophy of eyeball, prolapse of iris and aniridia, extrusion of crystalline lens, length of scleral wound greater than 10 mm and ruptured injury. These factors were also the risk factors of traumatic no light perception, excluded traumatic no light perception, prolapse of iris and aniridia. More than one risk factor usually co-exists in each eye., Conclusions: The eyes with traumatic no light perception have poor prognosis. However, 45% of them can achieve functional and anatomic success undergone vitrectomy. Eyes with no light perception are related to the combination of various risk factors. MSCH, severe retinal injury and extensive ciliary body injury are the main risk factors for poor prognosis.

Objective: To study the clinical manifestations of acute zonal occult outer retinopathy (AZOOR) and to differentiate it from other retinal diseases., Methods: Six patients diagnosed AZOOR had complete eye examinations including fundus photography, fundus fluorescein angiography (FFA), electroretinography (ERG), visual evoked potentials and visual field examination. Medical consultation and neurological consultation were performed in those patients. All patients were followed up and the data were collected for analysis, discussion, diagnosis and differential diagnosis., Results: Six patients (five female and one male) aged 26 - 42 years (mean 35 years) with AZOOR were followed up for 4 - 18 months [mean (7.5 +/- 3.2) months]. All of them were affected bilaterally and their visual acuity were slightly reduced except one eye was CF/40 cm. Half of them had photopsia. At least one eye of each patient had visual field defect or decreased sensitivity in local area or blind-spot enlargement. Biomicroscopic examination revealed vitreous cells in 10/12 eyes and anterior chamber inflammatory cells and keratic precipitate in 4/12 eyes. Minimal (10/12 eyes) or no (2/12 eyes) fundus changes were found in their initial examination. Funduscopic examination revealed yellow-white dots (4/12 eyes) and gray dots (6/12 eyes) at the posterior pole of deep retina or retinal pigment epithelium-Bruch membrane-choroid capillary complex layer. FFA showed depigmentation (2/12 eyes) or hyperfluorescein spots (10/12 eyes) that identical to the retinal lesions. In the follow-up examination, the visual acuity was reduced in one eye and visual field defect enlarged in both eyes of one patient; the number of retinal dots increased in one eye, decreased in one eye and extinguished in one eye. ERG or mERG revealed abnormal in all of their eyes with no changes in their follow-up examination. All of the initial diagnoses of six patients were not consistent with final diagnosis., Conclusions: AZOOR is a rare eye disease, usually occurs in young females, with the characteristics of photopsia, visual field defects, abnormal ERG and slight changes in the fundus. The differential diagnosis of this disease is relatively complicate and is easily to be misdiagnosed.