视网膜色素上皮细胞体外凋亡过程中钙离子平衡与caspase-3基因表达

目的:研究钙通道拮抗剂-维拉帕米(verapamil,Ver)诱导视网膜色素上皮(retinal pigment epithelium,RPE)细胞凋亡过程中钙离子及凋亡基因caspase-3变化。方法:应用80mg/L的Ver分别作用健康人眼RPE细胞12,24及48h诱导凋亡,设立对照组。逆转录聚合酶链反应(RT-PCR)检测凋亡基因caspase-3的表达,采用Fluo-3/AM负载技术,MetaFluo4.5/coolsnapfx/IX70细胞内钙离子荧光成像系统测定每组20个RPE细胞钙荧光值,并计算RPE细胞内钙浓度([Ca2+]i)。结果:对照组RPE细胞Ca2+荧光分布胞核最强,胞质次之。Ver作用12,24及48h后,细胞内[Ca2+]i明显降低(P<0.01)。对照组RPE细胞可见caspase-3的mRNA有少量的表达。Ver作用12h后,可见caspase-3的mRNA有较高的表达,与对照组比较,具有显著性差异(P<0.01)。随着Ver作用时间的延长,caspase-3的mRNA表达逐渐增强,在48h时有所下降。结论:Caspase-3基因表达上调及RPE细胞内钙离子稳态失调可能在Ver诱导RPE细胞凋亡中起关键作用。     

ET-1 对人视网膜色素上皮细胞内游离钙浓度的影响

目的观察内皮素(endothelin-1,ET-1)对体外培养视网膜色素上皮(retinal pig-mental epithelium,RPE)细胞内游离钙离子浓度([Ca2 ]i)的影响。方法用共聚焦显微镜观察1×10-12～0.1×10-6mol.L-1ET-1作用后fluo-3/AM负载的RPE细胞[Ca2 ]i的变化和地塞米松(dexamethasone,DEX)与染料木黄酮对其作用的影响。结果含钙溶剂DMEM液溶解的ET-1,RPE细胞[Ca2 ]i随着ET-1浓度的增加,反应敏感(F=8.228,P<0.01)。无钙溶剂D-Hank液溶解的ET-1,RPE细胞[Ca2 ]i随着ET-1浓度的增加,反应较差(F=1.843,P>0.05),而DEX和染料木黄酮抑制了1×10-9mol.L-1ET-1诱导的[Ca2 ]i的升高(F=9.945,P<0.01;F=17.864,P<0.01)。结论ET-1刺激使[Ca2 ]i升高,ET-1使[Ca2 ]i升高可能主要来自细胞外Ca2 的内流;DEX和染料木黄酮抑制ET-1的作用。     

不同浓度维拉帕米及不同光照形式对豚鼠RPE细胞Ca2+的影响

目的:探讨不同浓度维拉帕米(verapamil,Ver)对体外培养豚鼠视网膜色素上皮(retinal pigment epithelium,RPE)细胞内Ca2+浓度的影响,并比较有无Ver作用下经不同形式光照后RPE细胞内Ca2+浓度的变化。方法:2周龄幼年健康豚鼠10只,体外培养RPE细胞,传代、鉴定后,将细胞分为Ver处理组和未处理组,Ver处理组加入80mg/LVer作用12h。两组均进一步分为聚焦光组、离焦光组、平行光组和空白对照组,前三组分别接受聚焦光、离焦光(均为将平行光经透镜转化)和平行光照射,空白对照组不接受照射。于照射后立即采用激光扫描共焦显微镜(laser scanning confocal microscopy,LSCM)测定细胞内Ca2+荧光强度,分析不同光照形式与效应的关系。统计学方法采用单因素方差分析。结果:Ver作用于RPE细胞12h后,20,40,80mg/L组的细胞凋亡情况与空白对照组相比均无统计学意义(P>0.05),Ver可降低RPE细胞内Ca2+荧光强度,浓度为20,40,80mg/L时分别降低了10.36%,24.54%,58.05%,仅80mg/L组与无光照组相比差异有统计学意义(P<0.05)。未加Ver对RPE细胞进行光照,聚焦光组的Ca2+荧光强度较其他各组明显升高,离焦光组的荧光强度也较高,组间比较有统计学差异(P<0.05)。加入80mg/LVer对RPE细胞作用12h后再进行光照,光照各组Ca2+荧光强度没有明显提高,组间比较没有统计学差异(P>0.05)。结论:超过一定浓度的Ver可诱导RPE细胞凋亡,80mg/L可在不引起RPE细胞凋亡的前提下有效降低细胞内Ca2+荧光强度;不同光照形式对豚鼠RPE细胞内Ca2+有明显刺激作用,聚焦光影响最大;不同光照形式对Ver处理的RPE细胞内的Ca2+荧光强度无明显作用。     

枸杞多糖对蓝光损伤的视网膜色素上皮细胞的保护作用

目的:研究不同浓度的枸杞多糖对蓝光诱导损伤的体外培养人视网膜色素上皮(human retinal pigment epithelium,hRPE)细胞的保护作用。方法:通过蓝光诱导建立hRPE细胞光损伤模型,分别用不同浓度的枸杞多糖(分别为0.01,0.1,1mg/mL)对体外培养的hRPE细胞进行干预,通过流式细胞仪检测各实验组的细胞线粒体活性氧和凋亡率。实验组分为正常对照组、光照损伤组以及不同浓度枸杞多糖(0.01,0.1,1mg/mL)干预组。结果:线粒体活性氧检测:正常对照组荧光强度最小;蓝光损伤组荧光强度最大,不同浓度枸杞多糖处理组荧光度与蓝光损伤组强度相比,荧光强度差异有统计学意义(P<0.05)。Annexin V-FITC/PI凋亡检测显示不同浓度枸杞多糖干预组凋亡细胞数量与蓝光损伤组凋亡细胞相比差异均有统计学意义(P<0.05);1mg/mL枸杞多糖干预组凋亡细胞数量与对照组凋亡数量相比差异无统计学意义(P>0.05)。结论:枸杞多糖能抑制蓝光诱导损伤的hRPE细胞的凋亡,1mg/mL枸杞多糖抑制蓝光诱导的hRPE细胞凋亡的作用更强,其作用机制可能与抑制细胞线粒体产生活性氧有关。     

Bcl-2及bFGF在维拉帕米诱导人视网膜色素上皮细胞凋亡中的表达

目的探讨维拉帕米(verapamil,Ver)对体外培养的人视网膜色素上皮(retinal pigment epithelium,RPE)细胞的凋亡作用,观察凋亡过程中原癌基因蛋白质(Bcl2)和碱性成纤维细胞生长因子(baic fibroblast growth factor,bFGF)的表达变化。方法应用80mg·L-1Ver作用于体外培养的人RPE细胞12h、24h、48h,吖啶橙(acridineorange,AO)荧光染色及透射电镜观察RPE细胞凋亡;逆转录聚合酶链反应(RTPCR)检测Bcl2mRNA和bFGFmRNA表达变化。结果经Ver作用的体外培养的人RPE细胞具有典型的凋亡形态学特征:核染色质浓染、边集;细胞体积缩小。同时RPE细胞Bcl2mRNA表达下降;而bFGFmRNA表达随着作用时间延长,呈增高趋势。结论Ver可诱导体外培养人RPE细胞凋亡,凋亡过程中Bcl2表达逐渐下降,而bFGF表达增强。     

三氟啦嗪对视网膜色素上皮细胞游离钙和三磷酸肌醇的影响

增生性玻璃体视网膜病变 (proliferative vitreoretinopathy,PVR)是一种严重的致盲性眼病 ,因此 ,研究药物对 PVR的防治作用具有重要的临床意义。本研究拟用钙调素 (calmodulin,Ca M)抑制剂——三氟啦嗪 (trifluoperazine,TFP)作用于体外培养的豚鼠视网膜色素上皮 (retinal pigment epithelium,RPE)细胞 ,应用 IP3[3H]检测系统测定 RPE细胞内 IP3浓度的动态变化 ,同时 ,应用 Fura- 2 / AM荧光负荷技术测定 RPE细胞内游离 Ca2 ([Ca2 ]) i水平的变化 ,探讨在 TFP抑制 RPE细胞增生过程中 ,IP3与 [Ca2 ]i浓度的关系。1　…     

nmhaFGF和haFGF 对放线菌素D诱导的人视网膜色素上皮细胞凋亡的保护作用

目的 探讨非促分裂型人酸性成纤维细胞生长因子(non-mitogenic human acidic fibmblast growth factor,nmhaFGF)和 haFGF对放线菌素D诱导的人视网膜色素上皮(human retinal pigment epithelium,hRPE)细胞凋亡的保护作用,同时探讨2种浓度放线菌素D诱导hRPE细胞凋亡模型的复制条件.方法 用0.25 mg·L-1和0.50 mg·L-1放线菌素D诱导hRPE细胞凋亡,用琼脂糖凝胶电泳检测2种浓度放线茵素D诱导hRPE细胞DNA断裂情况,并用流式细胞仪检测放线菌素D诱导hRPE细胞的凋亡率,确定诱导hRPE细胞凋亡的条件,分另q以0.02 mg·L-1、0.06 mg·L-1、0.18 mg·L-1、0.54 mg·L-1和1.62 mg·L-1的nmhaFGF和haFGF预作用于hRPE细胞24 h,并设置正常细胞组和凋亡模型细胞组,观察nmhaFGF和haFGF对hRPE细胞凋亡的作用.结果 0.25 nag·L-1和0.50 mg·L-1放线菌素D诱导hRPE细胞凋亡16 h后细胞凋亡率分别为32.68%和53.27%.琼脂糖凝胶电泳结果显示0.25 mg·L-1放线菌素D诱导细胞凋亡条带清晰,而0.50 mg·L-1放线茵素D诱导hRPE细胞凋亡条带模糊,因此0.25 mg·L-1放线菌素D作用hRPE细胞16 h是诱导hRPE细胞凋亡的最佳条件.在nmhaFGF各剂量组中,随着nmhaFGF浓度升高,hRPE细胞凋亡率明显降低,其中1.62 mg·L-1剂量组细胞凋亡率最低,为(11.49±0.50)%;相同浓度haFGF各剂量组细胞凋亡率也呈现不同程度的降低,但随着haFGF剂量升高,凋亡率下降的趋势不如nmhaFcF剂量组明显,在haFGF剂量组中,1.62 mg·L-1剂量组细胞凋亡率最低,为(14.35±1.02)%,nmhaFGF和haFGF对hRPE细胞凋亡率的下降作用经比较差异无统计学意义.结论 haFGF和nmhaFGF都可以发挥对hRPE细胞凋亡的保护作用.该保护作用可能是通过发挥其非促分裂活性实现的.     

不同浓度维拉帕米及不同光照形式对豚鼠RPE细胞Ca^2＋的影响

目的：探讨不同浓度维拉帕米（verapamil,Ver）对体外培养豚鼠视网膜色素上皮（retinal pigment epithelium,RPE）细胞内Ca^2＋浓度的影响,并比较有无Ver作用下经不同形式光照后RPE细胞内Ca^2＋浓度的变化。方法：2周龄幼年健康豚鼠10只,体外培养RPE细胞,传代、鉴定后,将细胞分为Ver处理组和未处理组,Ver处理组加入80mg/L Ver作用12h。两组均进一步分为聚焦光组、离焦光组、平行光组和空白对照组,前三组分别接受聚焦光、离焦光（均为将平行光经透镜转化）和平行光照射,空白对照组不接受照射。于照射后立即采用激光扫描共焦显微镜（laser scanning confocal microscopy,LSCM）测定细胞内Ca^2＋荧光强度,分析不同光照形式与效应的关系。统计学方法采用单因素方差分析。结果：Ver作用于RPE细胞12h后,20,40,80mg/L组的细胞凋亡情况与空白对照组相比均无统计学意义（P〉0.05）,Ver可降低RPE细胞内Ca^2＋荧光强度,浓度为20,40,80mg/L时分别降低了10.36%,24.54%,58.05%,仅80mg/L组与无光照组相比差异有统计学意义（P〈0.05）。未加Ver对RPE细胞进行光照,聚焦光组的Ca^2＋荧光强度较其他各组明显升高,离焦光组的荧光强度也较高,组间比较有统计学差异（P〈0.05）。加入80mg/LVer对RPE细胞作用12h后再进行光照,光照各组Ca^2＋荧光强度没有明显提高,组间比较没有统计学差异（P〉0.05）。结论：超过一定浓度的Ver可诱导RPE细胞凋亡,80mg/L可在不引起RPE细胞凋亡的前提下有效降低细胞内Ca^2＋荧光强度;不同光照形式对豚鼠RPE细胞内Ca^2＋有明显刺激作用,聚焦光影响最大;不同光照形式对Ver处理的RPE细胞内的Ca^2＋荧光强度无明显作用。     

三氧化二砷诱导人晶状体上皮细胞凋亡的机制研究

目的 研究三氧化二砷(As2O3)对离体培养的人晶状体上皮细胞(FHL124)的凋亡及其作用机制.方法 实验研究.四甲基偶氮唑盐比色法观察As2O3对FHL124细胞的抑制作用;原位缺口末端标记(TUNEL)法测定细胞凋亡;Taqman实时荧光定量PCR检测基因表达的变化;荧光显微镜动态监测细胞内Ca2+浓度的变化.As2O3对FHL124细胞的生长抑制和细胞内Ca2+浓度的变化采用t检验进行分析;3种基因不同处理组间表达水平差异的比较采用Wilks'λ检验;单个基因比较采用LSD-t检验.结果 As2O3(3×10-7～1×10-4mol/L)对FHL124细胞的作用呈浓度依赖性,1 μmol/L As2O3即可显著抑制FHL124细胞的生长,半效抑制量(IC50)为1.5 μmol/L.TUNEL检测证实As2O3诱导FHL124细胞凋亡,引起FHL12A细胞DNA断裂.实时定量荧光PCR结果显示,As2O3可以引起FHL124细胞与内质网应激信号传导有关的基因产物EIF2A,ERN1和ATF6显著增加(F=8.51,P=0.0005).细胞内Ca2+测定显示As2O3降低细胞内Ca2+浓度,从而降低了Ca2+信号的峰值.20 μmol/L As2O3孵育30 min后,峰值降低了(66.34±4.47)%(P=0.0018),60 min则降低了(96.95±7.98)%(P=0.0002).20 μmol/L As2O3使Ca2+内流幅值及速度分别降低了(22.59±2.98)%和(39.69±6.01)%.结论 As2O3抑制FHL124细胞的生长并诱导细胞凋亡,诱导内质网应激可能是其重要作用机制之一.     

维生素E对大剂量蓝光诱导损伤视网膜色素上皮细胞的影响

目的:研究维生素E(Vit E)对大剂量蓝光诱导人视网膜色素上皮(hRPE)细胞损伤的影响,为减少蓝光损伤hRPE细胞的预后方案提供思路。方法:用3000±150Lx蓝光建立hRPE细胞损伤模型;利用流式细胞术检测照射时间分别为0、3、6、9、12、24h的6组hRPE细胞凋亡率及活性氧相对量;利用流式细胞术检测照射0h组、照射6h组、照射6h前或后加不同浓度Vit E组(Vit E的浓度分别为10、50、100μmol/L)的hRPE细胞凋亡情况和活性氧相对量,并采用Hoechst 33258试剂染色在荧光显微镜下观察hRPE细胞的荧光强度。结果:与照射0h组相比,照射3、6、9、12、24h组的hRPE细胞活性氧相对量明显增加(均P<0.01),照射6、9、12、24h组的hRPE细胞凋亡率也明显增加(均P<0.01),但照射3h组的hRPE细胞凋亡率无明显增加,差异无统计学意义(P=0.46)。与照射6h组相比,除照射6h前加入10μmol/L的hRPE细胞凋亡率(P=0.66)外,其他加Vit E的实验组hRPE细胞活性氧相对量和凋亡率明显减少、细胞中Hoechst 33258释放蓝色荧光逐渐减弱,且呈浓度依赖(均P<0.01)。与照射0h组相比,加Vit E的6组hRPE细胞活性氧相对量和凋亡率有差异(均P<0.01)。同一浓度的Vit E,除10μmol/L Vit E的hRPE细胞凋亡率在照射前或后加无差异(P=0.08)外,照射后加Vit E组比照射前加Vit E组的hRPE细胞活性氧相对量、凋亡率明显减少(均P<0.01)。结论:hRPE细胞经蓝光照射后出现胞内活性氧相对量增多的现象早于细胞凋亡,清除胞内活性氧是减少大剂量蓝光诱导hRPE细胞损伤的思路。Vit E可保护由大剂量蓝光诱导的RPE细胞损伤,这种效应随Vit E浓度增加而增强,且照射后加入比照射前加入的效果更好。但需要一定剂量的Vit E才能显效,而且无法完全修复损伤。     

Follow-up studies in pattern VECP in demyelinating diseases in children

Spectral sensitivity functions and the transient decrease of sensitivity to short wavelengths after the offset of yellow light (transient tritanopia) were measured by increment threshold techniques in patients suffering from hereditary macular degenerations. Color vision defects were determined by arrangement tests and the anomaloscope. Central areolar choroidal dystrophy was found to produce a mild protan defect and to reduce foveal spectral sensitivity throughout the visible spectrum by a factor of 100; it also abolishes transient tritanopia. Electroretinogram (ERG) was normal, electrooculogram (EOG) subnormal. Stargardt's disease, despite numerous fluorescent macular spots, does not abolish transient tritanopia nor does it reduce spectral sensitivity, although scotopic matches were performed on the Nagel anomaloscope. Only in severe, advanced cases was transient tritanopia reduced and spectral sensitivity found to follow the absorption spectrum of rods. Routine ERGs and EOGs were normal. Vitelliform macular degeneration, despite the ophthalmoscopically pronounced dystrophic macula, produced only very small changes in spectral sensitivity and transient tritanopia, although a widened matching range on the Nagel anomaloscope and electrophysiological abnormalities were found. Apparently damage of the retinal circuit which connects long and short wavelength-sensitive cones, caused by hereditary conditions, is different from that caused by retinotoxic drugs.     

p53 expression in pterygium in two climatic regions in Turkey

Purpose:

To assess accumulation of p53 protein in samples of primary pterygium from people living in two different climatic regions in Turkey.

Materials and Methods:

Group 1 included 101 pterygium specimens from people in Adana located in southern Turkey. Group 2 included 39 pterygium specimens from people in Ankara, located in the middle of Turkey. Climatic conditions throughout the year are sunnier and warmer in Adana than they are in Ankara. The control group (Group 3) included 30 specimens of conjunctiva that had been excised during cataract surgery from 30 patients without pterygium. The pterygial specimens and control conjunctiva were studied by immunohistochemistry using antibodies against p53 protein. Pearson''s chi-square test was used to compare the p53 immunoreactivity.

Results:

The p53 immunoreactivity in Groups 1 and 2 was greater than it was in the control group (P<0.001). There were no differences in p53 immunoreactivity between Groups 1 and 2 (P= 0.060).

Conclusion:

The p53 immunoreactivity was not correlated with ultraviolet irradiation exposure. The p53 immunoreactivity in our pterygium specimens suggests that pterygium could be a result of uncontrolled cell proliferation.     

Orthokeratology practice in children in a university clinic in Hong Kong*

Purposes: The aim of this study was to analyse clinical data of children undergoing orthokeratology (ortho‐k) and to investigate patients’/parents’ perspective on ortho‐k via telephone interviews. Methods: Clinical records of children undergoing ortho‐k from a university optometry clinic were reviewed and the effects of ortho‐k on refraction, vision and cornea were investigated. A telephone interview was conducted to solicit patients’/parents’ perspective of the treatment. Results: One hundred and eight files were reviewed. Median age of the children was nine years (range six to 15); mean (±SD) pre‐treatment refractive sphere was ‐3.56 ± 1.49 D and the median refractive cylinder was ‐0.50 D (range zero to ‐4.25 D). Significant refractive spherical reduction (58 per cent), improvement in unaided vision and corneal topographical changes were noted after only one night of wear. No significant change in astigmatism was found. Corneal staining was the most commonly observed complication with ortho‐k and more than 80 per cent of patients were advised to apply ocular lubricants to loosen the lens before lens removal. Ortho‐k was mainly undertaken for myopic control and about 90 per cent of the respondents reported good/very good unaided vision after ortho‐k and ranked the treatment as satisfactory or very good. Lens binding and ocular discharge were the most frequently reported problems during the treatment. Conclusion: Under close monitoring, overnight ortho‐k is effective and safe for reducing low to moderate myopia and the treatment is well accepted by the children.     

Changes in Bruch's membrane in experimental hypercholesteremia in rats

PURPOSE: We investigated the effect of high cholesterol diet for the aging changes in Bruch's membrane of rats. METHODS: After feeding a 4% cholesterol diet for 15 weeks to three young rats 3 months old and four aged rats 23 months old, we observed the morphological changes of Bruch's membrane by electron microscopy, and made a comparison with rats fed an ordinary diet. RESULTS: In one young rat fed a high-cholesterol diet, the endothelial basement membrane of the choriocapillaris formed multiple folds separated from the plasma membrane of the endothelium and showed lamellar thickening and crack in some areas. The elastic fiber layer in Bruch's membrane disappeared partly and some new microfibrils appeared. In one aged rat fed a high-cholesterol diet, the endothelial basement membrane of the choriocapillaris showed more lamellar thickening with lumps in some parts. Compared with rats fed an ordinary diet, rats fed a high-cholesterol diet showed thickening of the basement membrane and the changes were more severe. CONCLUSIONS: Our data indicated that high-cholesterol diet might promote age-related changes of Bruch's membrane.     

Trends in Patterns of Anterior Uveitis in a Tertiary Institution in Singapore

Purpose: To report the trends in etiology of patients with anterior uveitis (AU) in Singapore over 6 years.

Methods: A retrospective review of the clinical records of all new patients who presented with anterior uveitis to the uveitis subspecialty clinic from 2005 to 2010 at Tan Tock Seng Hospital, Singapore.

Results: There were 552 new cases of AU. This comprised 59.5% of a total of 928 new patients diagnosed with uveitis from 2005 to 2010. The mean age was 48.0?±?17.2 years. There was a male predominance (62.5%), with a male:female ratio of 1.7:1. The majority were of Chinese ethnicity (69%), followed by Malays (13.2%). Most cases were unilateral (79.5%) and idiopathic (50.4%). Common etiological causes included Fuchs heterochromic iridocyclitis (FHI) (5.6%), ankylosing spondylitis (AS)-related AU (5.1%), herpes simplex virus (HSV) (4.7%), and herpes zoster virus (HZV) (4.5%). There were increasing trends in AS-related AU from 3.2% in 2008 to 6.5% in 2010, and psoriasis-associated AU from 1.7% in 2005 to 4.0% in 2008. There were decreasing trends in the incidence of FHI from 10.6% in 2006 to 4.7% in 2009. No change in incidence of viral etiologies was noted, but cytomegalovirus-related immune-recovery uveitis (IRU) comprised 7.4%. IRU showed an increasing trend from 1.7% in 2005 to 11.9% in 2007, then decreased to 3.3% in 2010. Using the Pearson chi-square test, there was no statistically significant association between ethnicities (Chinese, Malay, Indian) comparing infectious and noninfectious cases (p?=?0.788), idiopathic and nonidiopathic cases (p?=?0.170), or between the various etiologies of uveitis (p?=?0.168).

Conclusions: AU was the predominant form of uveitis seen at our centers. Infectious etiologies (18.5%) are the most common among nonidiopathic cases, with herpes viruses (9.2%) being most prevalent. Despite increased use of polymerase chain reaction (PCR) in the detection of microbial and viral DNA, there was no overall increase in detection of infectious causes for uveitis. The changes in CMV-related immune recovery uveitis from 2005 to 2010 could reflect a change in HIV management in Singapore.     

弱视眼底光学相干断层扫描的研究进展

弱视是由于视觉发育关键期内各种异常的视觉经验导致单眼或双眼最佳矫正远视力低于正常同龄儿童,而眼部无明显器质性病变。目前普遍观点认为,弱视的发病机理主要源于视皮层。近年来,光学相干断层扫描（OCT）作为一种先进的活体成像技术,促进了对视网膜形态结构的大量研究,同时也被应用到弱视的研究领域。陆续有不同的研究人员利用OCT发现弱视患者眼底视网膜、脉络膜等眼部结构存在改变。笔者将对弱视眼底OCT的研究进展做一综述。     

Advances in imaging in oculoplastics

Color Doppler imaging, computed tomography (CT) and magnetic resonance (MR) imaging are the most precious imaging tools for the clinician in the field of oculoplastics. Orbital and facial vasculature, with its dynamic changes and flow velocities seen in orbital varices, carotid-cavernous fistulas, and dural cavernous arteriovenous malformations, is best detected by Color Doppler imaging. Computed tomography remains the dominant imaging modality in the evaluation of orbital trauma. Helical CT axial scanning with multiplanar reconstruction and three-dimensional CT imaging are most helpful in assessing iatrogenic, traumatogenic, and teratogenic orbital abnormalities. Despite its poor histologic specificity, MR imaging provides superior soft tissue contrast, and contrast-enhanced MR imaging has an established role regarding soft tissue tumor infiltration. The greatest value of MR studies in the evaluation of orbital and palpebral tumors is that it has the capacity to show the precise relation between lesions and adjacent structures before the clinician contemplates a surgical approach. Finally, contrast-enhanced MR imaging proved to be a valuable vascularization indicator based upon the extent of relative enhancement within porous orbital implant in anophthalmic socket.     

内毒素诱导的大鼠葡萄膜炎的巨噬细胞中Toll样受体4的表达

目的 探讨在内毒素诱导的Wistar大鼠葡萄膜炎中Toll样受体4(TLR4)阳性细胞与虹膜组织中巨噬细胞的动态变化和分布.方法 实验研究.Wistar大鼠50只,用随机数字法随机分为5组,每组10只,分别为正常对照(0 h)组、6 h组、12 h组、24 h组及48 h组.除0 h组外其余各组均足垫部注射霍乱弧菌内毒素200μg,注射后于裂隙灯显微镜下观察双眼前节炎症反应变化.按实验分组于0、6、12、24、48 h处死大鼠.取虹膜一睫状体及脉络膜组织.通过葡萄膜铺片免疫组织化学方法检测TLR4和巨噬细胞的标记CD163的表达.人工计数虹膜中TLR4~+与CD163~+的细胞并计算细胞密度,计算圆形和多形性的CD163~+细胞占所有CD163~+细胞的百分比.进一步采用免疫荧光双标记检测TLR4和CD163共表达的情况.通过单因素方差分析分别对大鼠虹膜内阳性细胞密度以及圆形、多形性CD163~+细胞的百分比进行统计学检验.结果 正常大鼠虹膜睫状体组织不表达TLR4.6 h组有2只大鼠虹膜内可见少量TLR4~+细胞,12～48 h组所有大鼠虹膜内TLR4~+细胞明显增多(F=167.2,P＜0.001),虹膜内TLR4~+细胞密度分别为(506.1±39.5)个/mm~2(12 h组)、(492.3±54.5)个/mm~2(24 h组)及(663.8±150.2)个/mm~2 (48 h组).在注射LPS后12～48 h期间TLR4~+细胞形态无明显变化.0～48 h组大鼠虹膜内均有CD163~+细胞,0 h组圆形和多形性CD163~+细胞百分比为13%,12～48 h组其百分比约为80%,且圆形细胞主要位于虹膜基质层.免疫荧光双标记可见TLR4和CD163的共表达,TLR4位于细胞膜,CD163位于细胞质.5组大鼠脉络膜内均未见TLR4表达.结论 内毒素诱导的大鼠葡萄膜炎中虹膜内TLR4表达增高,部分虹膜固有巨噬细胞表达TLR4.TLR4可能在葡萄膜炎的发生发展中起一定作用.