α-晶状体蛋白在眼科疾病中的作用研究进展

α-晶状体蛋白是晶状体中重要的成分蛋白质,是由αA-和αB-亚基组成的四聚体蛋白质。近年来研究表明α-晶状体蛋白具有很多特性,包括分子伴侣活性、自激酶活性、磷酸化丝氨酸残基-19、45、59模式及通过抑制细胞凋亡蛋白酶前体-3的活化抗凋亡等,但其主要作用在于维持晶状体的结构和屈光性,此外,它还可与视网膜神经节细胞（RGCs）的细胞膜结合促进RGCs的存活和轴突的再生,部分改善视功能。α-晶状体蛋白分子伴侣活性的下降可导致其他晶状体蛋白的凝聚和酶的失活,与眼科疾病的发生密切相关。就α-晶状体蛋白的研究进展及其与眼科疾病的关系进行综述。     

频域光相干断层扫描：眼底影像检查技术的新时代

光相干断层扫描（OCT）技术从时域转入频域,使得图像的清晰度增加,分辨率提高。能够更好地观察视网膜各层组织结构及病理改变,并对病变进行三维立体重建,使得黄斑视网膜外界膜、视细胞内外段等改变清晰可见,不仅为临床诊断提供了更为详尽的图像信息,而且还有助于更加深入全面的了解眼底疾病的特征及病理机制,引领我们进入了一个眼底疾病观察的新时代。在应用过程中,需要了解OCT图像不同色彩表达的意义,重视随诊时图像采集部位的一致性。提倡通过频域OCT技术直接地对病变进行动态观察以及对多种眼底影像检查资料进行整合分析是今后眼底影像检查的发展方向。     

Craniosynostosis associated with ocular and distal limb defects is very likely caused by mutations in a gene different from FGFR,TWIST, and MSX2

Craniosynostosis caused by genetic factors includes a heterogeneous group of over 100 syndromes, most with autosomal dominant inheritance. Mutations in five genes (FGFR1‐, −2, −3, TWIST, and MSX2) causing craniosynostosis as the main clinical feature were described. In most of these conditions, there are also limb malformations. We report a two‐generation kindred segregating microcornea, optic nerve alterations and cataract since childhood, craniosynostosis, and distal limb alterations, with a great clinical intrafamilial variability. The ophthalmological problems here described seem to be unique to this genealogy while similar feet alterations were apparently only described in two other affected siblings with acro‐cranial‐facial dysostosis syndrome (ADS). However, ADS has an autosomal recessive inheritance instead of the dominant pattern of the present genealogy. The candidate exons of the five genes previously mentioned were tested through sequencing analysis presenting normal results in all cases. Therefore, clinical and laboratory analyses in our patients suggest that their phenotype represents a new syndrome very likely caused by mutation in a gene different from those studied. © 2002 Wiley‐Liss, Inc.     

CRISPR-Cas9基因编辑技术在眼科疾病中的应用

规律成簇间隔短回文重复（clustered regularly interspaced short palindromic repeat,CRISPR）及相关核酸内切酶9（CRISPR associated protein,Cas9）技术是一种由RNA指导核酸内切酶的基因编辑技术。该技术以其操作简便、基因敲除效率高、靶向精准、周期短等特点迅速被用于多个物种的基因组编辑及疾病基因治疗中。本文旨在对CRISPR-Cas9技术在构建眼科疾病模型和治疗眼科疾病中的应用进展进行综述。     

恶性青光眼诊断与治疗中几个值得重视的问题

恶性青光眼预后差,临床治疗棘手。然而,近年来由于发病机制研究的深入及现代玻璃体切除技术和超声乳化联合人工晶状体植入技术的发展,如能正确掌握这些新技术,预后可以得到极大的改观,部分病例甚至可以完全治愈。目前,早期漏诊或治疗不恰当是预后不良的重要原因,为提高本病的诊疗水平,我们必须重视临床上容易混淆的问题。本述评讨论的主要内容包括：诊断中眼压的标准,超声生物显微镜的诊断价值,以及治疗中如何掌握玻璃体切除手术和人工晶状体植入术指征等等。     

DNA甲基化在眼科疾病中的研究进展

DNA甲基化作为表观遗传修饰的重要形式,通过调控基因表达,在疾病发生发展中发挥重要作用。近年来,随着DNA甲基化研究的迅速开展、检测技术的不断提升,DNA甲基化修饰已成为探究疾病发病机制及探寻新的治疗方案的重要方法; 眼科不同亚专业疾病在DNA甲基化的基础研究方面也取得了很多突破,包括角膜上皮的修复、结膜上皮的细胞黏附与异常的基质重塑、眼组织纤维化与青光眼、氧化应激和炎症反应与细胞损伤、不同DNA甲基化水平与眼部肿瘤的关系等。本文旨在通过对不同眼科疾病DNA甲基化调控机制的相关研究进行概述,为眼病发病机制的研究、筛查、诊断及预防提供新思路。     

硅油填充眼核磁共振成像与A型超声测量结果比较

目的 观察并探讨核磁共振成像(MRI)用于硅油填充眼眼球视轴测量的可行性及其优缺点.方法 32例32只硅油填充眼纳入本研究.采用MRI横断面T1加权像(T1 WI)、T2加权像(T2WI)检测硅油前后间隙,以脂肪抑制后T2WI成像测量眼球视轴;以角膜顶点至黄斑中心凹距离作为视轴长度,此连线上测量硅油后间隙的厚度.A型超声采取坐位及仰卧位检查,坐位测量眼球视轴长度,改变超声传播速度以修正眼球视轴长度;仰卧位检测硅油后间隙.结果 MRI检测结果显示,硅油在T1WI像中信号较对侧玻璃体高,T2WI像中信号较玻璃体低,加脂肪抑制后硅油信号降低,化学位移伪影减少;受检眼玻璃体腔内均存在不同程度的硅油前后间隙,玻璃体后间隙厚度为(2.47±1.31)mm.A型超声检测结果显示,18只眼可检测到硅油后间隙,占56.25%.MRI、A型超声测量本组患者硅油填充眼视轴长度分别为(23.52±4.67)、(20.57±5.32)mm,两者比较,其差异有统计学意义(t=30.17,P＜0.05).结论 MRI能够用于硅油填充眼视轴测量,并对硅油前后间隙进行观察和测量.

Abstract：

Objective To investigate the feasibility of using magnetic resonance imaging (MRI) to measure the visual axis length in silicone oil filled eyeballs. Methods Thirty-two silicone oil-filled eyes of 32 patients were studied. The ante-silicone oil spaces (ASS) and retro-silicone oil spaces (RSS) on the visual axis was measured on the cross-sectional T1 weighted images (T1 WI) and T2WI, the length of the visual axis was measured on the fat-suppressed T2WI. The length of the visual axis was the distance from the corneal vertex to the macular foves, and it was also measured by A-mode ultrasound in sitting position with different ultrasonic velocity. The post-oil gap was also measured by A-mode ultrasound in supine position.Results Compared with the signal of the contralateral vitreous body, the silicone oil signal was higher on T1WI images, lower on T2WI images. After fat suppression, the silicone oil signal and chemical shift artifact were reduced. There were different levels of ASS and RSS in the vitreous cavity of all 32 cases, the RSS depth was (2. 47 ± 1.31) mm on average by MRI. However, RSS was detected in only 56.25%(18 cases) eyeballs by A-mode ultrasound. The visual axis length of silicone oil-filled eyes was (23.52 ±4.67) mm by MRI, and (20. 57±5.32) mm by A-mode ultrasound in sitting position. The differences between two measurements was statistically significant (t= 30. 17, P＜0. 05). Conclusions In addition to A-mode ultrasound, MRI might be another effective method to detect RSS and ASS, and to measure the axial length of silicone oil-filled eyes.     

青光眼诊断新技术需要临床应用评价

海德堡视网膜断层扫描仪、相干光断层扫描仪及偏振光激光扫描仪等检测技术广泛应用于青光眼临床诊断已有多年,但其实用价值和临床意义尚缺少明确而规范的评判标准.每种检测仪器均需要进行诊断试验评价,而评价方法应当正确、规范而严谨,重在早期诊断和不同指标诊断性能的具体分析.诊断技术只有在临床应用与应用评价相结合时,才能获得真正的发展,并进而解决实际问题.