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991.
王婧  胡小凤  赵丽  许卓再  陈巍  李上  许颖知  卢弘 《眼科》2011,20(4):262-266
目的观察野生型C3H/HeN小鼠和Toll样受体4(TLR4)基因缺陷型C3H/HeJ小鼠腹腔巨噬细胞在脂多糖(LPS)刺激下激活状态的差异,从体外途径探讨TLR4传导信号在前葡萄膜炎发病中的可能作用机制。设计实验研究。研究对象健康成年C3H/HeN和C3H/HeJ小鼠。方法常规提取两种小鼠腹腔巨噬细胞体外培养,按处理因素不同随机分六组:C3H/HeN小鼠LPS组、正常对照组、抗TLR4单克隆抗体加LPS组、抗TLR4单克隆抗体组;C3H/HeJ小鼠LPS组、正常对照组。各组在不同处理后1h、3h、6h、12h、24h五个时间点通过免疫荧光组织化学染色进行观察。主要指标TLR4传导途径中关键分子TLR4、髓样分化因子88(MyD88)、核因子-κB(NF-κB)免疫荧光强度及表达位置差异。结果所有组TLR4均表达于细胞膜,MyD88表达于细胞质和细胞核。C3H/HeN小鼠LPS组和C3H/HeJ小鼠LPS组TLR4荧光强度比较,差异有统计学意义;余各组TLR4荧光强度两两比较,差异无统计学意义。C3H/HeN小鼠腹腔巨噬细胞LPS组随LPS刺激时间的延长,各观察时间点MyD88荧光强度逐渐减弱,总体差异有统计学意义;余各组各时间点MyD88荧光强度无明显变化。C3H/HeN小鼠正常对照组、抗TLR4单克隆抗体组,C3H/HeJ小鼠正常对照组腹腔巨噬细胞各时间点NF-κB均表达于胞质,C3H/HeN小鼠腹腔巨噬细胞LPS刺激1h后NF-κB表达于胞核,3h依旧表达于胞核,此后无法检测到NF-κB的表达。C3H/HeN小鼠抗TLR4单克隆抗体加LPS组、C3H/HeJ小鼠LPS组巨噬细胞经LPS刺激1h后NF-κB转移至胞膜,直至24h一直表达于胞膜。结论腹腔巨噬细胞TLR4传导途径中核因子的转位可能与前葡萄膜炎的发病有关,特异性阻断该途径或许为前葡萄膜炎的治疗提供新思路。  相似文献   
992.
目的 探讨高糖对人视网膜色素上皮(RPE)细胞表达血管内皮生长因子(VEGF)及色素上皮源性生长因子(PEDF)的干预作用.方法 采用HRPE细胞株,将细胞分为正常对照组(NG,5.6 mmol/L葡萄糖)、高糖组(HG,15、20、30 mmol/L葡萄糖)、高渗组(HM,24.4 mmol/L甘露醇+5.6 mmol/L葡萄糖).应用逆转录PCR(RT-PCR)技术检测VEGF及PEDF mRNA的表达.用ELISA技术检测细胞上清液中VEGF蛋白的表达.结果 高糖作用下VEGFmRNA和蛋白表达显著增高,PEDFmRNA的表达受到显著抑制.结论 高糖可从转录水平及蛋白水平诱导HRPE细胞VEGF的表达,并抑制PEDF的表达.  相似文献   
993.
目的:研究含缬酪肽蛋白(valosin-containing protein,P97)对高糖培养的人视网膜血管内皮细胞的作用。方法:体外高糖培养人视网膜血管内皮细胞(HRCECs),转染P97的RNA干扰质粒到HRCECs,抑制P97的表达,观察血管内皮生长因子(VEGF)的mRNA水平变化,同时观察HRCECs增殖的变化。结果:RNA干扰P97组和对照组的VEGF/actin分别为:0.21±0.03和0.10±0.01,两组差异有显著性(P<0.05),RNA干扰P97组和对照组,HRCECs在G1期细胞分别为44.05%±3.62%、25.21%±3.20%,两组比较差异有显著性(P<0.05)。结论:当P97表达受抑制后,VEGF的表达增高,HRCECs的增殖增强,这些变化可能与DR的发生发展相关。  相似文献   
994.
和敏感性意义.乡村学生课余看电视时间明显多于城市学生.结论 城乡学生视力低常的主要原因是近视.影响因素主要是长时间近距离作业,遗传,环境因素等;电视对近视的影响相关性小.  相似文献   
995.
目的研究经腺病毒介导,转染有人脑源性神经营养因子(brain-derivedneu-rotrophicfactor,BDNF)基因的SD大鼠雪旺细胞(Schwanncells,SCs)对成年SD大鼠视神经夹伤后修复的保护作用。方法将人BDNF基因转染到体外培养的SCs内,采用酶联免疫反应(enzyma-linkedimmumosorbentassay,ELISA)检测培养液上清中BDNF的表达量。80只成年SD大鼠随机分为转染有BDNF基因的SCs治疗组(A组)、正常SCs治疗组(B组)、DMEM治疗组(C组)和手术对照组(D组),每组20只,每只右眼建立视神经夹伤模型,D组大鼠左眼作为空白对照组(E组)。夹伤前7d进行荧光金(fluorogold,FG)逆行标记视网膜神经节细胞(retinalganglialcells,RGCs)。夹伤后即刻向A、B、C组伤眼玻璃体腔内注入相应液体各10μL。分别在伤后第7d、14d、21d、28d时进行闪光视觉诱发电位(flashvisualevokedpotentials,FVEP)检测和全视网膜铺片、记数RGCs。结果转染有BDNF基因的SCs的BDNF表达量明显高于正常SCs。A组的P1波幅比随观察时间延长呈下降趋势,但在夹伤后第14d、21d、28d时仍明显高于其他各组(P<0.05)。夹伤后第21d和第28d时,A组RGCs数分别为(1591±82)·mm-2、(1516±91)·mm-2,明显高于除E组外的其他各组(P<0·01)。结论视神经夹伤后,玻璃体腔内注射转染有BDNF基因的SCs能够促进RGCs轴突的修复,提高RGCs存活率,保护视神经功能,对视神经损伤修复具有明显的保护作用。  相似文献   
996.
Objective.?Changes in the maternal plasma concentrations of angiogenic (placental growth factor (PlGF) and vascular endothelial growth factor (VEGF)) and anti-angiogenic factors (sEng and vascular endothelial growth factor receptor-1 (sVEGFR-1)) precede the clinical presentation of preeclampsia. This study was conducted to examine the role of maternal plasma PlGF, sEng, and sVEGFR-1 concentrations in early pregnancy and midtrimester in the identification of patients destined to develop preeclampsia.

Methods. This longitudinal cohort study included 1622 consecutive singleton pregnant women. Plasma samples were obtained in early pregnancy (6–15 weeks) and midtrimester (20–25 weeks). Maternal plasma PlGF, sEng, and sVEGFR-1 concentrations were determined using sensitive and specific immunoassays. The primary outcome was the development of preeclampsia. Secondary outcomes included term, preterm, and early-onset preeclampsia. Receiving operating characteristic curves, sensitivity, specificity, positive and negative likelihood ratios, and multivariable logistic regression were applied. A p-value of <0.05 was considered significant.

Results.?(1) The prevalence of preeclampsia, term, preterm, (<37 weeks) and early-onset preeclampsia (<34 weeks) was 3.8 (62/1622), 2.5 (40/1622), 1.4 (22/1622) and 0.6% (9/1622), respectively; (2) Higher likelihood ratios were provided by ratios of midtrimester plasma concentrations of PlGF, sEng, and sVEGFR-1 than single analytes; (3) Individual angiogenic and anti-angiogenic factors did not perform well in the identification of preeclampsia as a whole; in particular, they perform poorly in the prediction of term preeclampsia; (4) In contrast, a combination of these analytes such as the PlGF/sEng ratio, its delta and slope had the best predictive performance with a sensitivity of 100%, a specificity of 98–99%, and likelihood ratios for a positive test of 57.6, 55.6 and 89.6, respectively, for predicting early-onset preeclampsia.

Conclusions.?(1) The PlGF/sEng ratio and its delta and slope had an excellent predictive performance for the prediction of early-onset preeclampsia, with very high likelihood ratios for a positive test result and very low likelihood ratios for a negative test result; and (2) Although the positive likelihood ratios are high and the positive predictive values low, the number of patients needed to be closely followed is 4:1 for the PlGF/sEng ratio and 3:1 for the slope of PlGF/sEng.  相似文献   
997.
目的探讨酸性成纤维细胞生长因子(aFGF)在宫颈癌发生发展中的作用及其信号传导机制.方法应用逆转录-聚合酶链反应技术(RT-PCR)对36例宫颈癌组织aFGF 及其受体FGFR1的表达进行了分析;并以不同浓度的aFGF 和酪氨酸蛋白激酶(TPK)抑制剂genistein诱导宫颈癌细胞株HeLa细胞,[γ-32P]ATP掺入外源性底物的方法,液体闪烁测定蛋白激酶C(PKC)及细胞外信号调节激酶(ERK)的活性.结果 aFGF mRNA 和FGFR1 mRNA在宫颈癌组织中的半定量检测结果分别为(1.233±0.064)和(1.168±0.103),与正常宫颈组织相比,差异有显著性(P<0.05),且在Ⅲ~Ⅳ期宫颈癌中的表达水平明显高于Ⅰ~Ⅱ期(P<0.05);随着aFGF浓度的增加,HeLa细胞PKC及ERK 活性随之升高,与aFGF浓度呈剂量依赖效应;genistein抑制细胞内PKC及ERK 活性,与genistein 浓度亦呈剂量依赖效应.结论提示aFGF 与宫颈癌的发生、发展、浸润呈正相关,其受体具有TPK活性,TPK激活后可进一步激活PKC和ERK,进一步证明PKC及ERK确是TPK的下游信号分子.  相似文献   
998.
目的:探讨活血通脉利水明目作用的中药散血明目片防治视网膜静脉阻塞(retinal vein occlusion,RVO)并发新生血管的作用。方法:将家兔48只96眼随机分为4组,每组12只24眼。A健康空白组;B模型组;C血栓通组;D散血明目片组。采用激光光凝法建立兔RVO模型,分别于术后3,7,14,21d用空气栓塞法处死动物,即刻摘取眼球石蜡包埋切片。免疫组化法观察兔视网膜组织中血管内皮生长因子(VEGF)和碱性成纤维细胞生长因子(bFGF)的表达。结果:成功建立了RVO模型。D组与B组比较,视网膜组织中VEGF含量(21d时分别为0.442±0.034和0.583±0.056)和bFGF含量(21d时分别为0.419±0.040和0.514±0.056)明显减少,差异有统计学意义(P<0.05),与C组比较差异无统计学意义。结论:活血通脉利水明目之散血明目片能抑制视网膜面VEGF和bFGF的高表达。  相似文献   
999.
Juan Chen  Xue Ding  Wei Du  Xin Tang  Wen-Zhen Yu 《国际眼科》2021,14(11):1666-1673
AIM: To evaluate the potential efficacy and mechanisms of nintedanib in corneal neovascularization (NV) in rabbit models. METHODS: Corneal NV was induced using 1 mol/L NaOH. Rabbits (n=21) were randomized to 3 groups: Group 1 were treated with 0.9% NaCl, Group 2 with Avastin (5 mg/mL), and Group 3 with nintedanib (1 mg/mL). All treatments started 1d after alkaline burns and were topically performed 3 times a day for 2wk. Photographs were taken on a slit lamp microscope on day 7 and 14. The NV area, the length of the vascularization and angiogenesis index (AI) were used to evaluate the corneal NV. On day 14, the immunohistochemical (IHC) studies of the cornea were examined. Western blot was performed to test the expression levels of vascular endothelial growth factor (VEGF), Akt, p-Akt, P38, p-P38, MMP-2 and MMP-9. RESULTS: The corneal NV area, vessel length and AI in Group 3 were significantly lower than Group 2, with both being lower than Group 1. IHC staining showed that VEGF was significantly overexpressed in the epithelium and stroma of cornea following alkaline burns. In contrast, the level of VEGF was significantly suppressed in both Group 2 and Group 3. Western blot results further confirmed that, compared with Group 1, Group 3 had significantly reduced expressions of VEGF, Akt, p-Akt, p-P38, MMP-2, and MMP-9 in corneal tissues. Trends of lower levels of MMP-2, AKT, and p-AKT in Group 3 than Group 2 were identified. CONCLUSION: Nintedanib and Avastin can effectively inhibit corneal NV, with P38 MAPK and AKT signaling pathways being possibly involved. Nintedanib seems more effective than Avastin and has the potential to be a novel therapy for preventing corneal NV.  相似文献   
1000.

AIM

Age-related macular degeneration (AMD) is the leading cause of blindness in the developed world and complement factor H (CFH) polymorphism has been found to associate with the AMD. To investigate whether the Y402H variant in CFH is associated with AMD in Chinese populations, a systematic review and meta-analysis were performed to estimate the magnitude of the gene effect and the possible mode of action.

METHODS

A meta-analysis was performed using data available from ten case-control studies assessing association between the CFH Y402H polymorphism and AMD in Chinese populations involving 1538 AMD. Data extraction and study quality assessment were performed in duplicate. Summary odds ratios (ORs) and 95% confidence intervals (CIs) an allele contrast and genotype contrast were estimated using fixed- effects models. The Q-statistic test was used to assess heterogeneity, and Funnel plot was used to evaluate publication bias.

RESULTS

Seven of ten case-control studies were neovascular AMD, and few studies came from west and north of China. There was strong evidence for association between CFH and AMD in Chinese population, with those having risk allele C 2.35 times more likely to have AMD than subjects with T allele. Evidence of publication bias was not observed in our meta-analysis.

CONCLUTION

This meta-analysis summarizes the strong evidence for an association between CFH and AMD in Chinese and indicates each C allele increasing the odds of AMD by 2.33-fold.But more evidences about the relation between CFH polymorphism and different type of Chinese AMD from various district were needed.  相似文献   
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