白内障晶状上皮细胞及晶体纤维超微结构的观察

应用胎儿晶状体发育的超微结构为形状学依据，观察老年性、外伤性、先天性白内障晶状体的超微结构。结果：老年性白内障晶状体上皮多数细胞破裂，作者首先发现其原因是相邻细胞顶部的紧密连结缺失，房水侵入所致。     

胎儿晶状体囊及晶状体上皮发育过程的光,电镜观察

应用手术显微镜、光、电镜观察了不同胎龄晶状体囊的血管、晶状体囊及晶状体上皮超微结构的发育.其结果表明:囊的前面的血管是来自虹膜小环.囊后面的血管是来自透明动脉.血管随胎龄增长而逐渐减少,直至第32周完全消失.晶状体上皮细胞超微结构的发育是:随胎龄增长上皮细胞由立方形→低立方形;核由长椭圆形→扁椭圆形.胞质中各种细胞器逐渐减少.但细丝逐渐增多,此提示晶状体的弹性与日俱增.而粗面内质网在胎龄第5～6个月时最为发达,这说明晶状体蛋白质的合成旺盛,以提供晶状体上皮向晶状体纤维过渡所需的物质基础.文内并就先天性和后天性白内障的病因进行了讨论.     

胎儿晶状体纤维发育的光,电镜观察

本文应用光、电镜分别观察36例和18例不同胎龄胎儿晶状体纤维的发育及其超微结构的变化。结果表明晶状体纤维的发生来自于晶状体后部及赤道部的囊下上皮细胞。幼稚带核的晶状体纤维细胞分布于外围。经增殖,延伸并挤向中心,去核后成为成熟的纤维细胞分布于深部。成熟的纤维细胞依次挤向核心成老化的新陈代谢低下的晶状体纤维细胞,构成晶状体核,而幼稚的和成熟的纤维细胞构成晶状体皮质。文中并就晶状体纤维细胞的发育及它们之间连结的正常生理功能进行讨论。为进一步探讨白内障晶状体纤维的病理改变提供形态学依据。     

年龄相关性白内障晶状体上皮细胞的超微结构观察

目的探讨年龄相关性白内障晶状体上皮细胞的超微结构变化。方法10例年龄相关性皮质性白内障的晶状体上皮细胞分为膨胀期组(8例)和成熟期组(2例),用日本产AEM-1200型透射电镜对其超微结构进行观察、对比。结果成熟期组晶状体上皮细胞与膨胀期组相比出现大量异型核、染色质凝缩、内质网扩张明显、线粒体肿胀、变空严重,嵴变形扭曲且大量减少或消失,呈现空泡化,且呈现明显的凋亡表现。结论晶状体上皮细胞不同时期的超微结构改变与白内障的发生发展密切相关。     

糖尿病性白内障晶状体上皮细胞的电镜观察

目的 研究糖尿病性白内障晶状体上皮细胞的形态学变化.方法 用透射电镜观察对10例糖尿病性白内障及2例正常晶状体上皮细胞的超微结构变化.结果 10例糖尿病性白内障晶状体上皮细胞与正常对照组相比晶体前囊膜晶体上皮细胞间隙增大明显,排列不规则.核变形及线粒体空泡化非常明显,嵴变形扭曲且大量减少或消失,呈现空泡化,内膜和外膜均...     

热休克蛋白-70、-27在外伤性白内障晶状体上皮细胞的表达

目的探讨热休克蛋白-70(heatshockprotein-70,HSP-70)和-27(HSP-27)在外伤性白内障晶状体上皮细胞中的表达及意义。方法采用Envision免疫组织化学染色,检测外伤性白内障的晶体12例。正常人带有前囊膜的晶状体6例,晶状体上皮细胞中Hsp-70、HSP-27的表达,并进行阳性细胞计数。结果HSP-70、HSP-27在外伤性白内障(83.8%±7.6%)、(68.5%±5.2%)和正常人(18.3%±6.4%)、(14.5%±5.7%)在晶状体上皮细胞表达中有统计学意义(P<0.05)。结论HSP70、HSP27可能在外伤性白内障的发生、发展中起重要作用。     

先天性遗传性白内障的基因学研究进展

先天性白内障是儿童常见的致盲性疾病,发病机制多种多样。非同系的人群中,大部分遗传性白内障是外显率较高的常染色体显性遗传,但也有X连锁和常染色体隐性遗传存在。随着分子生物学技术的发展,已经明确了先天性白内障的十几个基因、几十个独立位点的突变。基因学研究有助于揭示早期白内障的发病机制,为晶状体的发育和生理学研究提供新的见解,有助于进一步了解遗传、环境和营养等因素对晶状体的作用方式;遗传白内障的致病基因可能是老年性白内障的致病因素之一。就遗传性白内障的基因学研究进展进行综述。     

老年性白内障晶状体纤维细胞水通道蛋白-0表达变化

目的:观察老年性白内障晶状体纤维细胞水通道蛋白-0(AQP-0)的变化。方法:因其他疾患行眼球摘除术的18例患者晶状体为对照组;60例老年性核型白内障为病例组,根据晶状体浑浊程度进一步分为3组:晶状体核Ⅱ级组、Ⅲ级组和Ⅳ级组,各20例,均接受囊外摘除术取出晶状体核。凝集素抗体结合共聚焦显微镜观察晶状体纤维细胞形态,免疫印记法检测水通道蛋白-0的表达水平。结果:病例组晶状体纤维细胞排列紊乱、形态异常;晶状体核Ⅳ级组AQP-0低于Ⅲ级组,Ⅲ级组低于Ⅱ级组,组间均有统计学差异。结论:老年性白内障患者晶状体纤维细胞形态异常,随病情加重AQP-0的表达呈下降趋势。     

先天性遗传性白内障的基因学研究进展

先天性白内障是儿童常见的致盲性疾病，发病机制多种多样。非同系的人群中，大部分遗传性白内障是外显率较高的常染色体显性遗传，但也有X连锁和常染色体隐性遗传存在。随着分子生物学技术的发展，已经明确了先天性白内障的十几个基因、几十个独立位点的突变。基因学研究有助于揭示早期白内障的发病机制，为晶状体的发育和生理学研究提供新的见解，有助于进一步了解遗传、环境和营养等因素对晶状体的作用方式；遗传白内障的致病基因可能是老年性白内障的致病因素之一。就遗传性白内障的基因学研究进展进行综述。     

TGF-β1、bFGF在先天性白内障晶状体上皮细胞内表达增强

近年来,细胞因子与白内障关系的研究很多,但在先天性白内障患者中的表达尚未见报道。我们通过检测TGF-β1、bFGF在先天性白内障晶状体上皮细胞内的表达,以期为探讨先天性白内障的发病机制提供一些依据。1材料与方法1.1标本采集1.1.1研究组:标本取自山东大学第二医院眼科2004年12月—2006年5月行白内障摘除的先天性白内障患者13例,共16只眼,男7例女6例,排除合并其他先天性疾病,年龄3月~8岁,平均2.5岁。白内障囊外摘除过程中截取中央部晶状体前囊,立即置入去RNase酶的离心管,-80℃冰箱中保存。1.1.2对照组:同期因眼外伤,视网膜母细胞瘤等…     

Ultrastructural studies of traumatic cataractogenesis: Observations of a repair process in mouse lens

Lenses of CFl mice were studied with the transmission electron microscope at frequent intervals through 13 months following a transcorneal needle injury to the lens. While this kind of injury causes a high incidence of traumatic cataract in the human and frog, it elicits a repair process in the mouse lens whereby the damaged capsule, epithelium and lens fibers are rapidly renewed and permanent lens opacity seldom occurs. Ultrastructural changes in lens epithelial cells adjacent to the wound, which precede and accompany localized cellular proliferation and production of new capsule, involve a rapid increase or enlargement of organelles associated with protein synthesis and assembly. The capsule and epithelium are repaired within a couple of months. Cortical lens fibers in the wound area undergo conformational changes into smaller, ordered arrays of “membranous sacs.” These are replaced within a week by normal appearing lens fibers. There is minimal degeneration or hyperplasia noted, and except for a few fibroblastic cells on the lens surface, little evidence remains of the injury by two months. Ultrastructural differences between mouse and human lens, such as presence or absence of dense bundles of microfilaments and desmosomes are considered in relation to lens shape and tension, and susceptibility to injury-induced cataract.     

人工晶体植入前后视觉诱发电位的临床分析

目的:(1)探讨白内障囊外摘除术前术后及人工晶体植入术后视觉诱发电位幅值及潜时变化特征;(2)探讨白内障囊外摘除术术前P—VEP,F—VEP,F—ERG联合预测的必要性。方法:采用重庆泰克医电仪器公司产TEC—100C视觉电生理仪。对白内障患者实行分组测量。术前均测F—ERG,P—VEP,部分病例增测F—VEP。结果:114例术前F—ERG正常,P—VEP测量其P_(100)波幅值潜时均异常:P_(100)波幅值降低,潜时延长,术后及人工晶体植入后幅值,潜时都有所改善,而并发性白内障,代谢性白内障变化不明显。结论:据视觉诱发电位的变化,老年性白内障组,外伤性白内障组术后应及时装入人工晶体,并发性白内障组,代谢性白内障组装入人工晶体临床意义不大。术前联合测试(VEP ERG)对视力预后、以及眼底病变的定量诊断意义重大。     

An increase in apoptosis and reduction in αB-crystallin expression levels in the lens underlie the cataractogenesis of Morioka cataract (MCT) mice

We examined the morphological changes in fibers, localization of apoptotic cells, and protein expression of αB-crystallin in the lens of Morioka cataract (MCT) mice, a novel cataract model. Using a scanning electron microscope, swollen lens fibers and enlarged spaces between lens fibers were observed in the lens of 3-week-old MCT mice. At 2 weeks of age (before cataract), the single-strand DNA (ssDNA)-positive (indicating apoptosis) cell ratio of the lens epithelium was significantly higher in MCT than in wild-type ddY mice. At 2 and 4 weeks of age, αB-crystallin protein expression of the lens in MCT mice was significantly lower than that in wild-type ddY mice. These findings suggest that increase in apoptosis and reduction in αBcrystallin level are involved in the cataractogenesis of MCT mice.     

The role of autoimmune phenomena in the pathogenesis of cataract.

Investigations were carried out to clarify the role of autoimmune phenomena in the pathogenesis of cataract in the adult human lens. Studies were carried out to determine the presence of serum antibodies to lens protein in patients with senile cataract, in patients with diabetes mellitus with and without cataract, and in healthy adult controls using the interfacial test and the gel-diffusion technique. Non-specific antibodies were removed by adsorption of sera with homogenized rat liver. A high proportion of healthy adults was found to have anti-lens protein antibodies (44.4% by the gel-diffusion method). In contrast, patients with cataract and diabetic patients with no cataract demonstrated double this incidence (82% and 80%), while all diabetic patients with cataract showed the presence of antibodies (P = 0.0002). The possible causes for the development of lens antibodies in normal healthy humans are discussed. Also, the causes for the higher incidence of lens antibodies in patients with cataract and in diabetic subjects with no clinical evidence of cataract are considered in relation to cataract formation. Homogenates of cataractous lenses when investigated revealed the presence of both IgG and IgM immunoglobulins, the former probably to a greater extent. Fluorescent microscopy on cryosections of senile and diabetic cataractous lenses revealed the presence of immunoglobulins within the lens. The antigen in the immune complexes isolated from homogenized cataractous lenses was characterized by the SDS-polyacrylamide gel electrophoresis method. A single band was consistently obtained and the molecular weight of the protein was estimated to be between 35,000 and 40,000. The strong possibility of auto-antibodies to lens protein being of aetiological significance in the pathogenesis of cataract is discussed.     

Comparative study of serum Na(+ )and K(+ ) levels in senile cataract patients and normal individuals

Many factors such as aging, changes in blood electrolytes levels, and possibly family history are involved in senile cataract formation. Changes in serum electrolytes levels can induce changes in aqueous electrolytes levels and effect on lens metabolism and probably cataract formation. In this paper, we study serum level of Na(+ )and K(+) in senile cataract patients and normal individuals. Methods and materials: 155 senile cataract patients scheduled for cataract surgery in eye clinic of Rasoul hospital and 155 normal individuals were selected. Serum Na(+) and K(+) levels were measured by Flame Photometry technique and means compared between two groups by t-test. Results: 1. Mean serum Na(+) level in senile cataract patients and normal individuals was 144.96 +/- 6.04 mEq/lit and 140.88 +/- 2.27 mEq/lit respectively, and there was statistically significant difference (P<0.0001). 2. Mean serum K(+) level in senile cataract patients and normal individuals was 4.20 +/- 0.34 mEq/lit and 4.15 +/- 0.32 mEq/lit respectively, and there was no statistically significant difference. Conclusion: Serum Na(+ )level in senile cataract patients was higher than normal individuals in this study. This result might suggest that diets with high Na(+) content are a risk factor for age-related cataract formation, as high Na(+) content of the diet leads to high level of serum Na(+), which in turn contributes to formation of age-related cataract.     

The association of rubella virus in congenital cataract - a hospital-based study in India.

BACKGROUND: The association of rubella virus (RV) with congenital cataract has been well established. Since the data on association of RV with congenital cataract in India are scanty, a study was done based on virus isolation from lens aspirates in patients undergoing therapeutic lensectomy and serology. OBJECTIVE: To determine the incidence of the association of rubella virus with congenital cataract. STUDY DESIGN: The lens aspirates collected during the 9-year period (from 1990 to 1998), from 70 children up to 12 years of age with congenital cataract were processed for the isolation of rubella virus by conventional viral isolation culture method using BHK-21 and Vero cell lines. Identification of the virus was confirmed by immunofluorescence using human anti-rubella virus specific hyperimmune serum. Serum samples were collected from 55 out of these 70 children and the presence of antibodies to RV was detected by ELISA test. RESULTS: RV was isolated from lens aspirates in seven (10%) out of the 70 children with congenital cataract. Of the 55 sera tested, 22 had both anti-rubella IgM and IgG antibodies, in 13 only anti-RV IgG antibodies, in seven only IgM antibodies and the rest of the 13 samples did not have detectable levels of rubella antibodies. Among the children who had IgM antibodies, 12 (24.5%) were below the age of 6 months. CONCLUSION: It can be concluded based on virus isolation that 10% of patients with congenital cataract were due to rubella infection and the detection of 24.5% anti-RV IgM antibodies in children below 6 months old shows the possible association of rubella virus with congenital cataract.     

微小连续环形撕囊在膨胀期老年性白内障超声乳化手术中的应用

目的 研究膨胀期老年性白内障超声乳化中微小连续环形撕囊的安全性和短期手术效果.方法 对143例皮质膨胀期老年性白内障患者进行较小的连续环形撕囊,常规超声乳化手术,植入人工晶状体后,根据撕囊直径的大小,再扩大撕囊至6mm左右.对连续环形撕囊的完成率、术中、术后并发症和术后最佳矫正视力进行统计分析.结果 132例(92.3...