鼠神经生长因子对早期糖尿病大鼠玻璃体中感光细胞间维生素A类结合蛋白含量的影响

Objective To observe the effect of intravitreal injection of mouse nerve growth factor (NGF)on interphotoreceptor retinoid-binding protein(IRBP)in the vitreous of diabetic rats at early stages.Methods Ninety-six male Sprague Dawley(SD)rats were divided into control group(group A,24 rats)and experimental group(72 rats).The rats in experimental group were induced with streptozotocin injection for diabetic retinopathy model,and then randomly divided into positive control group(group B),normal saline group(group C)and NGF group(group D),24 rats in each group.The rats in the group A and B were not intervened.The rats were received intravitreal injection with 4μl normal saline(group C)or 4 μl(0.5 μg/μ1)NGF(group D).At 2,4,6 and 8 weeks after injection,IRBP levels were detected bv enzvmelinked immunosorbent assay(ELISA);hematoxylin-eosin(HE)staining and light microscope were used to observe the morphological changes of the retina;transmission electron microscope was used to observe the retinal uhrastructure.Results At 2 weeks after injection,there was no significant difference in IRBP expression between group A,B,C and D(F=2.833,P=0.052).At 4,6,8 weeks after injection,the differences of IRBP expression between group A,B,C and D were significant(F=22.252,108.459,105.726;P=0.000).At different time points after injection,there was no significant difference in IRBP expression of group A(F=1.462,P=0.241),but there were significant differences in IRBP expression of group B.C and D(F=150.98,63.519,64.604;P=0.000).Light microscope found that the retinal structure was clear in group A and in group B,C,D at 2,4 weeks after injection;the retinal thickness were thinner in group B,C,D at 8 weeks after injection.Transmission electron microscope displayed that the structure of rod outer segments was clear in group A and in group B,C,D at 2 weeks after injection;partly unclear structure of rod outer segments and slightly enlarged gap were observed in group B,C,D at 4,8Weeks after injection.Conclusion Intravitreal injection with NGF can stabilize the IRBP expression in the vitreous of diabetic rats at early stages effectively.     

鼠神经生长因子对早期糖尿病大鼠玻璃体中感光细胞间维生素A类结合蛋白含量的影响

Objective To observe the effect of intravitreal injection of mouse nerve growth factor (NGF)on interphotoreceptor retinoid-binding protein(IRBP)in the vitreous of diabetic rats at early stages.Methods Ninety-six male Sprague Dawley(SD)rats were divided into control group(group A,24 rats)and experimental group(72 rats).The rats in experimental group were induced with streptozotocin injection for diabetic retinopathy model,and then randomly divided into positive control group(group B),normal saline group(group C)and NGF group(group D),24 rats in each group.The rats in the group A and B were not intervened.The rats were received intravitreal injection with 4μl normal saline(group C)or 4 μl(0.5 μg/μ1)NGF(group D).At 2,4,6 and 8 weeks after injection,IRBP levels were detected bv enzvmelinked immunosorbent assay(ELISA);hematoxylin-eosin(HE)staining and light microscope were used to observe the morphological changes of the retina;transmission electron microscope was used to observe the retinal uhrastructure.Results At 2 weeks after injection,there was no significant difference in IRBP expression between group A,B,C and D(F=2.833,P=0.052).At 4,6,8 weeks after injection,the differences of IRBP expression between group A,B,C and D were significant(F=22.252,108.459,105.726;P=0.000).At different time points after injection,there was no significant difference in IRBP expression of group A(F=1.462,P=0.241),but there were significant differences in IRBP expression of group B.C and D(F=150.98,63.519,64.604;P=0.000).Light microscope found that the retinal structure was clear in group A and in group B,C,D at 2,4 weeks after injection;the retinal thickness were thinner in group B,C,D at 8 weeks after injection.Transmission electron microscope displayed that the structure of rod outer segments was clear in group A and in group B,C,D at 2 weeks after injection;partly unclear structure of rod outer segments and slightly enlarged gap were observed in group B,C,D at 4,8Weeks after injection.Conclusion Intravitreal injection with NGF can stabilize the IRBP expression in the vitreous of diabetic rats at early stages effectively.     

Comparison of lens oxidative damage induced by vitrectomy and/or hyperoxia in rabbits

AIM: To compare of lens oxidative damage induced by vitrectomy and/or hyperoxia in rabbit. METHODS: Sixteen New Zealand rabbits (2.4-2.5 kg) were randomly divided into two groups (Group A, n=12; Group B, n=4). In Group A, the right eyes were treated with vitrectomy and systemic hyperoxia (oxygen concentration: 80%-85%, 1 ATA, 4h/d) (Group A-right), and the left eyes were treated with hyperoxia without vitrectomy surgery (Group A-left). Four rabbits in group B (eight eyes) were untreated as the controls. Lens transparency was monitored with a slit lamp and recorded before and after vitrectomy. After hyperoxic treatment for 6mo, the eyeballs were removed and the lens cortices (containing the capsules) and nuclei were separated for further morphological and biochemical evaluation. RESULTS: Six months after treatments, there were no significant morphological changes in the lenses in any experimental group when observed with a slit lamp. However, the levels of water-soluble proteins and ascorbate, and the activities of catalase and Na+-K+-ATPase were significantly reduced, whereas the levels of malondialdehyde and transforming growth factor β2 (TGF-β2) were significantly elevated, in both the cortices and nuclei of eyes treated with vitrectomy and hyperoxia. The increase in protein-glutathione mixed disulfides and the reduction in water-soluble proteins were more obvious in the lens nuclei. The levels of ascorbate in the vitreous fluid were also reduced after vitrectomy, whereas TGF-β2 increased after vitrectomy and hyperoxia. Systemic hyperoxia exposure increased these effects. CONCLUSION: Removal of the intact vitreous gel with vitrectomy and exposing the lens to increased oxygen from the retina induce lens oxidation and aggregation. Thus, an intact vitreous gel structure may protect the lens from oxidative insult and maintain lens transparency.     

增殖型糖尿病视网膜病变玻璃体切割术后视力不良的相关因素研究

Objective To determine the incidence and predisposing factors for the poor visual acuity of less than 0.1 after vitrectomy in the treatment of proliferative diabetic retinopathy (PDR). Methods The clinical data of 95 cases (120 eyes) of PDR patients treated with vitrectomy were analyzed retrospectively. Compared the potential predisposing factors to the poor visual acuity between the two groups: one group with postoperative visual acuity of less than 0.1, the other group with postoperative visual acuity of 0.1 or more than 0.1. Results There were 37 (31%) eyes with postoperative visual acuity of less than 0.1. Univariate analysis revealed that there were association between the poor postoperative visual acuity and preoperative macular detachment、intraocular tamponade, postoperative high intraocular pressure, with no preoperative panretinal photocoagulation. Multivariate analysis revealed that there were great association between the poor postoperative visual acuity and preoperative macular detachment, postoperative high intraocular pressure. Conclusions The poor visual acuity of less than 0.1 after vitrectomy in the treatment of PDR has great association with preoperative macular detachment, postoperative high intraocular pressure.     

增殖型糖尿病视网膜病变玻璃体切割术后视力不良的相关因素研究

Objective To determine the incidence and predisposing factors for the poor visual acuity of less than 0.1 after vitrectomy in the treatment of proliferative diabetic retinopathy (PDR). Methods The clinical data of 95 cases (120 eyes) of PDR patients treated with vitrectomy were analyzed retrospectively. Compared the potential predisposing factors to the poor visual acuity between the two groups: one group with postoperative visual acuity of less than 0.1, the other group with postoperative visual acuity of 0.1 or more than 0.1. Results There were 37 (31%) eyes with postoperative visual acuity of less than 0.1. Univariate analysis revealed that there were association between the poor postoperative visual acuity and preoperative macular detachment、intraocular tamponade, postoperative high intraocular pressure, with no preoperative panretinal photocoagulation. Multivariate analysis revealed that there were great association between the poor postoperative visual acuity and preoperative macular detachment, postoperative high intraocular pressure. Conclusions The poor visual acuity of less than 0.1 after vitrectomy in the treatment of PDR has great association with preoperative macular detachment, postoperative high intraocular pressure.     

Comparison of outcomes of idiopathic macular holes treated by vitrectomy with air or silicone oil tamponade based on the hole size

AIM: To compare the efficacy of vitrectomy combined with air or silicone oil in the treatment of idiopathic macular hole (IMH). METHODS: According to the results of high-definition optical coherence tomography (HD-OCT), 75 cases (75 eyes) of IMH in stage II-IV (Gass stage) in the General Hospital of Chinese PLA from January 2017 to December 2019 were collected for this retrospective study. The best corrected visual acuity (BCVA) and minimum diameter of IMH (MMHD) were measured. Eyes underwent vitrectomy combined with internal limiting membrane peeling operation, and were divided into disinfection air group (30 eyes) and silicone oil group (45 eyes) according to the intraocular tamponade. For MMHD≤400 μm (MMHD1), there were 23 eyes in air group and 16 eyes in silicone oil group. For MMHD2>400 μm (MMHD2), there were 7 eyes in air group and 29 eyes in silicone oil group. One month after surgery, the closure rates of IMH and BCVA were compared and analyzed. According to HD-OCT, the closure shape was graded with A (bridge closure) and B (good closure). RESULTS: The closure rates of air group and silicone oil group were 86.67% and 95.56% respectively with no significant difference (P>0.05); For MMHD1, those of air group and silicone oil group were 95.65% and 100% respectively with no significant difference (P>0.05); For MMHD2, those of air group and silicone oil group were 57.14% and 93.10% respectively, and those of the silicone oil group were higher than the air group (P<0.05). There was no significant difference in the closure shape grade between MMHD1 air group and silicone oil group (P>0.05). The proportion of Grade B in MMHD2 silicone oil group was higher than that in the air group (P<0.05). BCVA of each group after operation was better than that before operation, and there was no significant difference between air group and silicone oil group. While among them, MMHD1 air group was better than silicone oil group (P<0.05), and there was no significant difference between MMHD2 air group and silicone oil group (P>0.05). CONCLUSION: For smaller IMH (≤400 μm), the efficacy of vitrectomy combined with air should be considered better than silicone oil; for larger IMH (>400 μm), the efficacy of silicone oil may be better than air.     

Changes in vitreous VEGF, bFGF and fibrosis in proliferative diabetic retinopathy after intravitreal bevacizumab

AIM: To evaluate the relationship between intravitreal bevacizumab (IVB) treatment and the levels of vitreous vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and vitreous-retina surface fibrosis in patients with proliferative diabetic retinopathy (PDR). METHODS: This study was a prospective, open-label, controlled, randomized clinical trial. Sixty-eight eyes of PDR patients (n=53) and macular hole patients (n=15) were enrolled in this study. Thirty-four eyes of the PDR patients received IVB before vitrectomy. Twenty-three of the 34 PDR patients received IVB treatment 5d before vitrectomy (subgroup a), and 11 of the 34 PDR patients received IVB treatment greater than 2wk prior to vitrectomy (subgroup b). Nineteen of the PDR patients did not receive IVB treatment at any time prior to vitrectomy. The levels of bFGF and VEGF in vitreous samples were measured using enzyme-linked immunosorbent assay (ELISA) and the degree of vitreoretinal fibrosis was characterized using clinical data and data obtained intra-operatively. RESULTS: In PDR patients, VEGF and bFGF levels were significantly increased compared to non-PDR (control) subject’s eyes (P<0.01). In PDR patients, vitreous VEGF levels were significantly decreased following IVB treatment compared to PDR patients that did not receive IVB treatment (P<0.01). The degree of vitreoretinal fibrosis was significantly increased in subgroup b compared to subgroup a(P<0.05) and to patients that did not receive IVB (P<0.05). Vitreous bFGF levels were significantly greater in subgroup b than subgroup a (P<0.01) or in patients who did not receive IVB treatment (P<0.05). A Spearman’s rank correlation test indicated that higher levels of vitreous bFGF, but not VEGF, correlated with the degree of vitreoretinal fibrosis. CONCLUSION: We found that bFGF levels increase in PDR patient’s vitreous after IVB treatment longer than two weeks prior to vitrectomy and correlated with the degree of fibrosis after IVB treatment. These findings suggest vitreous fibrosis is increased in PDR patients after IVB treatment may be due to increased levels of bFGF.     

Quantitative Study of Basic Fibroblast Growth Factor in Vitreous with Proliferative Vitreoretinopathy

Objective: To quantitatively study basic fibroblast growth factor (bFGF) in the vitreous of proliferative vitreoretinopathy (PVR) in orderto understand the role of bFGF in the development of PVR.Method: High sensitive sandwich enzyme immunoassay technique(ELISA) was used to measure bFGF level in vitreous of normal eyes, the eyes of PVR-C or PVR-D grade, eyes of vitreous hemorrhage and the serum levels of bFGF in PVR-D patients. Results: The levels of bFGF in the vitreous were: median 5. 20ng/L, quartile 15. 47 ng/L in 20 normal eyes; median 3. 12ng/L, quartile 10. 48 ng/L in 35 PVR-C eyes; median 46. 56 ng/L, quartile 113. 96 ng/L in 26 PVR-D eyes; median 1. 40 ng/L, quartile 6. 25 ng/L in 25 vitreous hemorrhage eyes. The vitreous bFGF level in PVR-D group was significantly higher than that in the normal group, PVR-C group and vitreous hemorrhage group ( P < 0. 01). The mean of serum-bFGF level was 18. 33 ± 3. 39 ng/ L. The vitreous bFGF level of PVR-D group was significantly higher than serum-bFGF lev     

Effect of intravitreal injection of bevacizumab-chitosan nanoparticles on retina of diabetic rats

AIM:To investigate the effects of intravitreal injection of bevacizumab-chitosan nanoparticles on pathological morphology of retina and the expression of vascular endothelial growth factor (VEGF) protein and VEGF mRNA in the retina of diabetic rats.METHODS: Seventy-two 3-month aged diabetic rats were randomly divided into 3 groups, each containing 24 animals and 48 eyes. Both eyes of the rats in group A were injected into the vitreous at the pars plana with 3μL of physiological saline, while in groups B and C were injected with 3μL (75μg) of bevacizumab and 3μL of bevacizumab-chitosan nanoparticles (containing 75μg of bevacizumab), respectively. Immunohistochemistry was used to assess retinal angiogenesis, real-time PCR assay was used to analyse the expression of VEGF mRNA, and light microscopy was used to evaluate the morphology of retinal capillaries.RESULTS:Real-time PCR assay revealed that the VEGF mRNA expression in the retina before injection was similar to 1 week after injection in group A (P>0.05), while theVEGF mRNA expression before injection significantly differed from those 4 and 8 weeks after injection (P<0.05). Retinal expression of VEGF protein and VEGF mRNA was inhibited 1 week and 4 weeks after injection (P<0.05) in group B, and the expression of VEGF protein and VEGF mRNA was obviously inhibited until 8 weeks after injection (P<0.05) in group C. Using multiple comparisons among group A, group B, and group C, the VEGF expression before injection was higher than at 1, 4 and 8 weeks after injection (P<0.05). The amount of VEGF expression was higher 8 weeks after injection than 1 week or 4 weeks after injection, and also higher 1 week after injection compared with 4 weeks after injection (P<0.05). No toxic effect on SD rats was observed with bevacizumab-chitosan nanoparticles injection alone.CONCLUSION: The results offer a new approach for inhibiting angiogenesis of diabetic retinopathy and indicate that the intravitreal injection of bevacizumab inhibits VEGF expression in retina, and bevacizumab-chitosan nanoparticles have a longer duration of action.     

Triamcinolone-assisted Pars Plana Vitrectomy for Retinal Disease

Purpose:To determine whether triamcinolone acetonide(TA)staining facilitates posterior hyaloid removal in patients undergoing pars plana vitrectomy (PPV) for retinal disease. Methods: A triamcinolone acetonide(TA)-assisted vitrectomy was performed on patients with the following disease: proliferative diabetic retionpathy(5eyes) , central retinal vein occlusion(5eyes) , macuar hole (3eyes) , and epiretinal membrane(2eyes). Eyes without apparent preoperative posterior vitreous detachment were enrolled in this study. After a core PPV, TA aqueous suspension (40 mg/ml) was injected into the mid vitreous cavity to visualize the posterior hyaloid, thus allowing a complete posterior hyaloid separation and removal. The visual acuity, intraocular pressure (IOP), tamponade, corneal pathology, after-cataract, vitreous hemorrhage, and necessity for reoperation were thereafter examined for at least 3 months after surgery. Results: In all patients, the vitreous body was clearly seen by means of triamcinolone during surgery, and complete removal of posterior hyaloid was facilitated and confirmed. Retina was attached in 14 of 15 eyes, and vision acuity was improved in 9 of 15 eyes. Two eyes showed transient postoperative IOP elevation, 2 eyes had after cataract formation and leye had cataract progression. Vitreous hemorrhage occurred in 1 eye. No eye had corneal pathology. Conclusion: Triamcinolone improved the visibility of the hyaloid and the safety of surgical procedures during PPV. No obvious adverse effect due to toxicity of TA accrued in TA-assisted PPV. Eye Science 2005;21:142-146.