幼兔角膜上皮细胞损害对角膜形态的影响

角膜上皮的损害可引起角膜细胞凋亡，甚至角膜基质层变薄。我们通过损伤幼兔角膜上皮．以观察角膜厚度和角膜曲率的变化。     

正常儿童生理性角膜散光的测量

正常儿童生理性角膜散光的测量黑龙江省眼病防治研究所张春起，李俊洙，张世元，王志鹏作者采用Ｂａｕｓｃｈ＆Ｌｏｍｂ角膜曲率计对２８９例５７８眼视力正常儿童进行角膜屈折力和角膜散光的测量，旨在探讨、提供儿童生理性角膜散光的分布规律及正常参数。对象与方法１９...     

强力霉素对人角膜上皮细胞FasL表达的影响

目的 观察正常人角膜FasL蛋白的表达情况，评价人角膜上皮细胞FasL蛋白对强力霉素反应的表达特性。方法 使用免疫组织化学染色观察正常人角膜上皮FasL的表达；用组织块培养法培养人角膜上皮细胞，将得到的细胞随机分为两组，一组使用含200μg／ml强力霉素的培养液，另一组不含强力霉素，分别再培养24h。运用流式细胞技术测定24h后FasL的表达情况。结果 FasL在正常人角膜上皮细胞中呈阳性表达；经强力霉素干预的角膜上皮细胞FasL的表达高于未经强力霉素干预的角膜上皮细胞（P〈0．01）。结论 正常人角膜上皮细胞有FasL的表达；强力霉素可使体外培养的人角膜上皮细胞FasL的表达增高，有望降低临床角膜上皮细胞移植后的免疫排斥反应。     

生长因子对角膜上皮细胞损伤修复的作用

角膜上皮细胞是维持角膜正常生理功能的重要细胞。角膜上皮缺损,一般修复较快,但也有些角膜疾患可导致持续性角膜上皮缺损,从而此起一系列并发症,一些生长因子可促进角膜上皮的修复,开创了治疗角膜上皮持续缺损的新方法,本着重介绍与角膜上皮细胞关系密切的表皮生长因子（EGF）、血小板源性生长因子（PDGF）、成纤维细胞生长因子（FGF）、转化生长因子（TGF）、肝细胞生长因子（HGF）和角质细胞生长因子（KGF）的结构及其在角膜上皮细胞修复中的作用。     

长期佩带角膜接触镜对角膜上皮细胞凋亡的影响

背景 配戴软性角膜接触镜作为矫正屈光不正的主要方法之一目前已广泛应用,临床上对其不良反应的研究已有报道,但是其对人角膜上皮细胞凋亡的影响研究甚少. 目的 检测长期佩戴软性角膜接触镜者与未配戴者的角膜上皮细胞的凋亡情况并进行对比,了解长期佩戴软性角膜接触镜对人眼角膜上皮细胞增生修复的影响.方法 采用回顾性巢式病例对照研究设计,纳入2010年10月至2011年6月在贵阳医学院附属医院就诊的行去瓣式机械法准分子激光角膜上皮瓣下磨镶术(Epi-LASIK)的患者40例80眼,其中包括长期佩戴软性角膜接触镜(≥5年)的近视患者20例40眼(戴镜组)及未配戴软性角膜接触镜的近视患者20例40眼(未戴镜组),在去瓣式Epi-LASIK术中收集患者的角膜上皮瓣,利用流式细胞技术检测角膜上皮细胞凋亡情况,并分析两组间角膜上皮细胞凋亡比例的差异. 结果 角膜上皮细胞凋亡流式细胞图显示,戴镜组患者角膜上皮annexin V高染、碘化丙啶(PI)低染的早期凋亡细胞群多于未戴镜组,而annexinV、PI均低染的角膜上皮活细胞群少于未戴镜组,annexin V、PI均高染的坏死细胞或晚期凋亡细胞多于未戴镜组.戴镜组角膜上皮细胞早期凋亡比例为(11.23±5.31)％,未戴镜组为(7.31±5.43)％,差异有统计学意义(t=2.754,P=0.008).结论 长期佩戴软性角膜接触镜可造成角膜上皮细胞的早期凋亡细胞比例增多,进一步证明角膜上皮长期处于损伤、增生修复、愈合到再损伤的过程,可能导致眼表结构及功能的紊乱.     

低浓度地塞米松对兔角膜上皮细胞的影响

目的: 探讨地塞米松(dexam ethasone,D EX)对培养的兔角膜上皮细胞和角膜上皮伤口愈合的影响。方法: 体外实验原代培养兔角膜上皮细胞, 用四唑盐(M TT)实验和流式细胞仪检测不同浓度 D EX 对兔角膜上皮细胞的作用, 同时通过 H E 、免疫组织化学染色和扫描电镜及临床观察兔角膜上皮细胞刮除后 0.1g/L D EX 用药组和对照组伤口愈合的情况。结果: M TT 检测显示小于 0.1g/L 浓度的 D EX 对兔角膜上皮细胞的生长无明显影响。流式细胞仪检测到 0.1g/L 浓度的 D EX 对兔角膜细胞生长周期无抑制作用。动物实验: 0.1g/L 地塞米松作用后上皮愈合时间显著性缩短, 两组中新生成的上皮细胞均有较强的 PC N A 蛋白的表达。0.1g/L 地塞米松组与对照组相比, 电子显微镜检查角膜基质排列更规则, 炎症反应较轻。结论: 低于 0.1g/L 浓度的地塞米松对培养的兔角膜上皮细胞的生长无抑制作用。0.1g/L 浓度的地塞米松眼液能有效的促进角膜上皮生长并降低炎症反应, 将有利于准分子激光角膜屈光手术后早期角膜伤口愈合。     

表皮生长因子对不同区域角膜上皮细胞体外传代培养的影响

目的　观察表皮生长因子 (EGF)对角膜上皮细胞体外传代培养的影响。方法　用抗 Brdu抗体标记法 ,流式细胞仪检测细胞增殖情况。结果　对照组 :中央部细胞传代次数为 ( 5± 1)代 ,周边部的为 ( 7± 1)代 ,角膜缘部的为 ( 8±2 )代。EGF组 :角膜中央及周边部上皮细胞传代次数分别提高 ( 1± 1)及 ( 2± 1)代 ;角膜缘部的增加 ( 5± 1)代。结论　角膜缘细胞在添加EGF后 ,细胞体外传代有显著提高 (P <0 .0 1)。由此提示 :通过进一步改善培养条件 ,体外延长角膜缘部细胞的存活是可能的     

角膜屈光术后角膜瓣下上皮细胞植入的研究进展

角膜瓣下上皮细胞植入或内生是角膜屈光术后并发症之一,近年来随着手术设备和技术的提高,其发生率已经明显降低。但外伤致角膜瓣移位发生角膜瓣下上皮植入病例仍时有报道。若上皮细胞植入处理不及时可引起患者屈光状态改变、角膜瓣融解等严重并发症。故本文对角膜屈光术后角膜层间上皮植入研究进展予以综述。     

表皮生长因子对兔角膜上皮细胞生长作用的实验研究

研究了表皮生长因子（ＥＧＦ）对角膜上皮细胞的生长影响，用氚标的胸腺嘧啶核甘（＾３ＨＴｄＲ）掺入法证明ＥＧＦ单独对角膜上皮细胞无生长促进作用，而当和角膜基质块同时培养时，ＥＧＦ能够明促进膜上细胞生长，不同浓度ＥＧＦ的每分钟放射性计数（ＣＰＭ）差异均具有显著性意义（Ｐ〈０．０５或Ｐ〈０．００１），并且随ＥＧＦ浓度增加对角增上皮细胞促生长作用增强。提示ＥＧＦ能促进角膜上皮细胞的生长作用，但需要角膜基质的     

体外角膜上皮细胞凋亡的研究

为观察离体角膜上皮细胞经传代培养后细胞死亡的规律及确定其性质。本文应用流式细胞仪 ( FACStarplus)检测凋亡细胞的亚 2倍体 DNA以及细胞凋亡的形态学观察 ,对体外培养的每一代兔角膜缘上皮细胞的凋亡情况进行了观察及分析。结果显示 :角膜缘原代上皮细胞被检测出 7.0 0± 2 .2 3 %的凋亡细胞 ;从第 6代开始 ,角膜上皮细胞凋亡数目显著升高 ( P<0 .0 1) ;之后细胞凋亡数目急剧增加 ,第 8～ 9代后细胞出现集体“自杀”现象。透射电镜观察到这些细胞出现了核浓缩、胞膜发泡、凋亡小体等典型细胞凋亡的形态学改变。结论 :离体角膜缘上皮细胞因外部生长环境的改变 ,在培养到第 6代时出现了细胞凋亡现象。     

Morphologic Effect of Hyperosmolarity on Rabbit Corneal Epithelium

The morphologic effect of hyperosmolarity, equivalent to that seen in the tear film of patients with keratoconjunctivitis sicca (KCS), on rabbit corneal epithelium in vitro and in vivo was studied. In the in vitro studies, corneal epithelium was grown in explant cultures. Control tissue was cultured in a 307 mOsm/L medium. Epithelium cultured in the 333, 361 and 363 mOsm/L media showed decreased intercellular connections, blunting and loss of microplicae, disruptions in cell membranes and cellular swelling with decreased cytoplasmic density. In in vivo studies, corneas bathed in balanced salt solutions (BSS) concentrated to 330, 360, or 407 mOsm/L showed increased cell desquamation, and the cell changes observed at similiar osmolarities in the in vitro studies. The tear film osmolarities observed in KCS are sufficient to cause the corneal epithelial changes seen in patients with this disease.     

The Effect of the Corneal Epithelium on the Intraocular Penetration of Fluoroquinolone Ophthalmic Solution

Purpose Pharmacokinetic studies of antibacterial agents for infectious eye diseases have usually been performed on normal rabbit eyes. In this study, the intraocular penetration of fluoroquinolone ophthalmic solutions was determined in normal rabbit eyes and in rabbit eyes that had the corneal epithelium intentionally removed.Methods We determined the intraocular penetration of ofloxacin (OFLX), levofloxacin (LVFX), and norfloxacin (NFLX), fluoroquinolone ophthalmic solutions that are already on the market and undergoing clinical studies, by injecting 50µl of each solution into the cul-de-sacs of rabbit eyes three times at 15-min intervals. The drug concentration at 10, 30, 60, 120, and 240min after final instillation was determined by high-performance liquid chromatography.Results The maximum concentration in the aqueous humor of normal rabbit eyes was 2.09 ± 1.56µg/ml (60min, OFLX), 2.57 ± 1.00µg/ml (30min, LVFX), and 0.42 ± 0.12µg/ml (120min, NFLX). The drug concentration in the aqueous humor of eyes with intentionally removed corneal epithelium was 12.50 ± 5.62µg/ml (30min, OFLX), 9.02 ± 2.45µg/ml (60min, LVFX), and 8.54 ± 5.17µg/ml (30min, NFLX). The drug penetration of the eye drops into eyes with removed corneal epithelium was around 6 times (OFLX), 3.5 times (LVFX), and 20 times (NFLX) higher than the penetration into the eye with normal cornea.Conclusion Among the pharmacokinetic parameters of the three ophthalmic solutions according to the one-compartment model, the maximum concentration in the aqueous and the area under the concentration–time curve in the aqueous tended to be higher in the eyes with intentionally removed corneal epithelia than in those with normal corneas. Jpn J Ophthalmol 2004;48:93–96 © Japanese Ophthalmological Society 2004     

Transmembrane Mucin 1 Blocks Fluorescein Ingress to Corneal Epithelium

PurposeTo determine the role of transmembrane mucins in blocking fluorescein ingress to the corneal epithelium and its deficiency in contributing to corneal fluorescein punctate staining.MethodsA dry eye model was established by extirpating lacrimal and Harderian glands in rabbits to correlate the expression of mucins with fluorescein-stained areas on the corneal button using immunofluorescence. Expression of transmembrane mucins was promoted in human corneal epithelial cells (HCECs) by culturing with the mucin-promoting medium (MPM) or diquafosol treatment. Conversely, the expression of mucins was downregulated by knockdown with short hairpin RNA. The role of mucin1 extracellular domain in fluorescein ingress was further verified by overexpression of N-terminally truncated mucin1 in HCECs.ResultsIn the rabbit dry eye model, the expression level of mucin1 was significantly decreased in superficial corneal epithelial cells where fluorescein punctate staining was observed. Upregulation of mucin1 and mucin16 in HCECs promoted by MPM or by diquafosol treatment impeded intracellular fluorescein ingress. Downregulation of mucin1 and mucin16 enhanced fluorescence ingress in HCECs after fluorescein staining. Overexpression of truncated mucin1 did not alter the fluorescein intensity of fluorescein-stained HCECs, supporting the notion that the ability of mucin1 to block fluorescein ingress was primarily mediated by its extracellular domain. Minimal inherent expression of mucin16 in the rabbit cornea limited the validation of its role in blocking fluorescein ingress in vivo.ConclusionTransmembrane mucin1 blocks fluorescein ingress in the corneal epithelium, explaining how fluorescein staining is positive when the level of transmembrane mucins is disturbed in dry eyes.     

氯霉素眼药水对角膜上皮细胞的毒性——组织培养法研究

用体外药物毒性试验法，观察氯霉素眼药水对人角膜上皮细胞的毒性。结果：５个药厂的氯霉素眼药水皆有不同程度的毒性，Ｅ厂最好，Ａ厂最差。估计与配方、包装和保存有关。５个药厂产品的ｐＨ值不一样，范围在６．７￣５．４之间，蓝色瓶装者较高，白色瓶装者较低，过期产品最低。日晒后ｐＨ值皆下降，白色瓶装者较明显，因阳光能加快氯霉素的分解。建议：眼药水的配合要合理，要用有色瓶包装，要有批号和有效日期，医药卫生部门应加     

人、兔角膜上皮在体外培养中的形态特征

应用组织培养技术对人、兔角膜上皮进行了培养,并对其形态及超微结构进行了观察。结果表明:培养的人、兔角膜上皮均呈不规则的多角形镶嵌排列,具有膜状生长的特点。细胞核大,圆或椭圆,有1～3个核仁。细胞骨架染色显示蓝色纤维状结构在细胞内的不同分布。扫描电镜可见表面微绒毛较多的暗细胞及较少的明细胞。透射电镜显出上皮除原有的细胞器外,还表现出核仁、张力丝、糖原、次级溶酶体、指状交叉等增多。     

Microvilli defects in retinas of ezrin knockout mice

Ezrin, a member of the ezrin/moesin/radixin (ERM) family, localizes to microvilli of epithelia in vivo, where it functions as a bridge between actin filaments and plasma membrane proteins. In the eye, ezrin has been localized to both apical microvilli of Müller cells and retinal pigment epithelium (RPE) apical microvilli and basal infoldings. In the present study, we analyze these structures in the eyes of early postnatal ezrin knockout mice. This analysis indicates that the loss of ezrin leads to substantial reductions in the apical microvilli and basal infoldings in RPE cells and in the Müller cell apical microvilli. The absence of apical microvilli in the RPE is accompanied by the presence of microvilli-like inclusions (MIs) in the RPE cytoplasm. Finally, photoreceptors in the ezrin knockout animals show substantial retardation in development as compared to their wild type littermates.     

电子烟对小鼠角膜上皮和结膜杯状细胞的影响

目的：研究电子烟对小鼠角膜上皮组织结构及结膜杯状细胞的影响。方法：实验研究。18只雄性c57BL小鼠,5～6周龄,随机分为A、B、C组,每组6只。A组不做任何干预,B组采用0 mg尼古丁电子烟进行干预,C组采用12 mg尼古丁电子烟进行干预。每日2次,每次30 min。干预12周后,行苏木精-伊红染色观察角膜上皮情况,透射电子显微镜下观察小鼠角膜上皮组织超微结构变化,免疫荧光染色观察Mucin 5AC阳性表达的杯状细胞的改变。各组间结果数据采用单因素方差（One-way ANOVA）分析和事后分析。结果：干预12周后,A组上皮细胞层数为5.0±0.7,而B、C组上皮细胞层数分别为7.0±0.7和7.0±0.6,A组与B、C组间差异有统计学意义（F=18.50,P<0.001）,而B组和C组间差异无统计学意义。与A组相比,B、C组角膜上皮微绒毛明显减少（F=153.50,P<0.001）,长度变短（F=29.54,P<0.001）,排列紊乱。在结膜穹隆部的上皮中,B组和C组的Mucin 5AC阳性细胞数目比A组明显减少（F=420.10,P<0.001）,但是B组和C组之间Mucin 5AC阳性细胞数目差异无统计学意义。结论：电子烟会损伤小鼠角膜上皮的组织结构,减少结膜杯状细胞的数目。     

Color Specular Microscopy of Disorders Involving the Corneal Epithelium

Color specular microscopy, a noninvasive, in vivo microscopic technique, was utilized to study the corneal epithelium in 17 patients including eight with keratoconus, seven with bullous keratopathy, and two with Fuchs' corneal dystrophy. Color specular microscopy was also performed on rabbit corneas with experimental surgical trauma. Changes observed by specular microscopy in these diseased states correlated with alterations noted by light microscopy and scanning and transmission electron microscopy. Specular microscopy can provide detailed in vivo cellular morphology of the ocular surface, obviating the need for tissue biopsy. Thus, specular microscopy is a valuable diagnostic technique available for the clinician to monitor changes of the diseased ocular surface.     

家兔干眼模型的角膜上皮超微结构及几种眼药的疗效

研究了家兔干眼模型的角膜上皮超微结构并藉以筛选干眼病的有效药物。40只家兔随机分为干眼模型组、0.1%必嗽平组、50%中药组和0.01%维甲酸治疗组。结果局用三种滴眼药14天后,必嗽平和中药组的上皮超微结构与干眼模型眼比较无明显变化,维甲酸组则见微绒毛和微皱襞复常,上皮覆盖,细胞无水肿,复常细胞计数的差异显著(P<0.01)。表明局用0.01%维甲酸能促进家兔干眼角膜上皮缺损的愈合和变性失活细胞的恢复。     

In Vivo Specular Microscopy of Edematous Human Corneal Epithelium with Light and Scanning Electron Microscopic Correlation

A wide-field contact specular microscope was used to examine and to photograph the corneal epithelium in 35 eyes with chronic corneal edema. Seven of the patients subsequently underwent corneal transplantation allowing for correlation of the in vivo findings with the light and electron microscopic appearance. The early findings on specular microscopy included loss of the clear superficial epithelial cell outlines with easy dislodgement of these cells and a fine pattern of edema outlining basal cells. Individual cellular edema and fluid-filled cysts occurring at various epithelial layers and subepithelially appeared with worsening swelling. Subepithelial connective tissue and anamalous basement membrane were present at later stages.