β—防御素及其在眼内组织中的表达

β-防御素是一些具有广谱抗菌活性的内源性抗生肽，在许多器官的粘膜防御中起重要作用。它存在于多种物种中，对革兰阳性和阴性菌、霉菌、厌氧菌、钩端螺旋体、分枝杆菌及某些包膜病莓等均有杀伤活发现 。本主要针对β-防御素及其在眼内组织中的表达作一综述，为各种原因起的眼表和眼内感染性疾病的防治提供新思路。     

β-防御素及其在眼内组织中的表达

β- 防御素是一些具有广谱抗菌活性的内源性抗生肽 ,在许多器官的粘膜防御中起重要作用。它存在于多种物种中 ,对革兰阳性和阴性菌、霉菌、厌氧菌、钩端螺旋体、分枝杆菌及某些包膜病毒等均有杀伤活性。本文主要针对 β 防御素及其在眼内组织中的表达作一综述 ,为各种原因引起的眼表和眼内感染性疾病的防治提供新思路。     

骨形态发生蛋白在眼部发育和眼科疾病发生中的作用

骨形态发生蛋白属转化生长因子β超家族成员,参与众多器官的发生与形成.近年研究发现,骨形态发生蛋白及其受体不仅在眼部组织的发育过程中有表达,而且还参与眼部疾病的发生过程,如角膜疾病、视网膜疾病和青光眼等,表明骨形态发生蛋白在眼部发育和眼病发生中可能具有一定的作用.     

内源性大麻素系统的降眼压及视网膜神经保护机制

内源性大麻素系统在眼部和视网膜中的研究已取得显著进展.研究表明,内源性大麻素系统广泛存在于整个眼球,分布和功能具有组织特异性.大麻素在许多中枢神经系统退行性疾病中具有神经保护作用,主要与其抑制兴奋性氨基酸和细胞因子的释放,以及对氧化应激的调制作用有关.利用药物调制内源性大麻素受体或与大麻素合成、运输及分解相关的酶类,被证明是这些疾病传统治疗之外的一种有效替代.本文中,我们将讨论内源性大麻素受体及其在眼组织中的定位,大麻素信号通路及其在眼部疾病研究中的最新进展.其中,不仅基于降低眼内压,还从视网膜神经保护方面,特别关注了大麻素在视网膜变性疾病中的药理作用和机制.针对眼部大麻素系统的分子干预,可为眼部疾病的基础研究以及治疗靶点的确定提供更广阔的思路.     

β-防御素在中耳炎发病机制中的作用

β-防御素是抗菌肽的一种,其各个亚型广泛表达于哺乳动物呼吸道,包括中耳上皮,与其他抗菌肽一起构成中耳上皮先天免疫屏障,对抗外界病原体的入侵.本文综述β-防御素的表达或功能变化与中耳炎发生、发展的关系.     

大麻二酚在眼部疾病中的应用前景

大麻二酚(Cannabidiol,CBD)为大麻提取物中的一种非成瘾性活性成分,是目前研究最热门的植物源性大麻素之一。内源性大麻素系统(endocannabinoid system,ECS)在眼表和视网膜中的研究也已经取得显著进展。CBD可以广泛存在于整个眼球,且其分布和功能具有组织特异性。近年来研究发现CBD具有良好的抗炎、抗损伤、降低眼压及神经保护作用。该文详细介绍了CBD在眼部疾病中的研究进展,以及其对各种眼部疾病的治疗潜力。此外,还讨论了CBD在临床眼科治疗中的应用面临的挑战和未来的发展方向。     

眼组织生物力学的研究

生物力学是研究组织或器官的力量与功能之间关系的学科,对研究眼科疾病的预防、发生、发展、诊疗具有重要作用.眼球是一个封闭的近似球体的器官,眼球内外的每一组织都有一定张力,而且相互联系,互为影响.眼内外及球壁某一局部组织的改变,可能会影响眼球某一区域组织的生物力学或功能的改变.随着生物力学的方法增多,大家越来越重视对眼部组织生物力学的研究,达到预防和治疗眼部疾病的目的.如使用胶原交联增强角膜的强度,防治圆锥角膜或扩张性角膜疾病;又如后巩膜加固术增强巩膜力学的方法来治疗或预防高度近视等.对眼外肌、角膜、巩膜、虹膜、晶状体的生物力学的研究是目前热点,本文就目前眼部生物力学的研究热点做一综述.     

SARS-CoV S蛋白功能性受体ACE2在人角膜、结膜中的表达

目的 检测人角膜、结膜中血管紧张素转化酶2(ACE 2)的表达,由此来初步推断重症急性呼吸综合征(SARS)冠状病毒由眼部入侵的可能。 方法 取成人眼球破裂伤摘除的眼角膜和结膜组织及4~6个月中期引产胎儿的眼角膜、结膜、心、肺组织,分别采用RT-PCR和免疫组化方法检测组织中ACE 2的表达。取成人尸体解剖的心、肺组织作为对照。 结果 在上述各种组织中均检测到了ACE 2的表达。 结论 眼角膜、结膜是人体暴露于SARS冠状病毒的一个重要部位,研究结果从mRNA和蛋白质水平证实了眼部组织存在SARS冠状病毒S蛋白的功能性受体ACE 2,由此初步推断SARS-CoV存在由眼部入侵的可能,为临床进一步研究SARS的防护和致病机制提供了线索。     

角膜穿通伤后炎症因子的表达特征及其在房水中相对含量的动态变化

目的 研究角膜穿通伤后炎症因子在眼球壁的分布特征及其在房水中相对含量的动态变化,初步探讨角膜穿通伤后眼内炎的发病机制.方法 清洁级成年雌性SD(Sprague Dawley)大鼠50只,随机分为正常对照组和角膜穿通伤后6h、24h、48h、72h组,每组各10只.角膜穿通伤组大鼠制作角膜穿通伤模型,分别用免疫荧光染色法检测损伤后各时间点眼球壁组织中热休克蛋白90(heat shock protein 90,HSP90)、肿瘤坏死因子-α(tumor necrosis factor α,TNF-α)、白细胞介素(interleukin,IL)-1β、IL-10的组织定位;并用免疫印迹法分别检测损伤后各时间点房水中上述因子相对含量的动态变化.结果 HSP90、IL-10、TNF-α和IL-1β在正常房水和眼球组织中含量较少.HSP90于损伤后6 h在房水中含量达到高峰,与其他各组相比差异均有统计学意义(均为P<0.05),随后逐渐减少,免疫荧光染色结果显示其主要表达于视网膜视锥和视杆细胞层;TNF-α、IL-1β于损伤后24 h在房水中达到高峰,与其他各组相比差异均有统计学意义(均为P<0.05),之后逐渐减少,主要表达于角膜、睫状体、视网膜;IL-10于损伤后72 h在房水中含量达到高峰,与其他各组相比差异均有统计学意义(均为P<0.05),主要表达于角膜和视网膜.结论 角膜穿通伤后应激反应可促使眼球局部炎症因子的表达,导致继发性炎症损伤角膜穿通伤后应早期局部使用免疫抑制剂抑制炎症反应,保护眼球壁组织细胞.     

人类防御素在眼科的研究进展

人类防御素是一类阳离子抗微生物肽大家族,分子量为4～5kDa,分子内含有6个二硫键相连的半胱氨酸残基。近年来,随着防御素的发现和研究,其广泛的抗微生物特性受到人们的关注,有可能成为一条新的抗感染途径。防御素已成为医学生物学和分子生物学研究的热点。本研究主要就防御素的结构特点、眼组织分布、眼表上皮表达与调控、生物学活性等相关研究进展进行综述。     

Are beta-adrenergic mechanisms involved in ocular hypotensive actions of adrenergic drugs?

Specific beta 1- and beta 2-adrenergic agonists and antagonists were studied for their effects on aqueous humor dynamics in a cat model. Tazolol (beta 1-agonist) reduced formation of aqueous humor more than outflow, while metoprolol (beta 1-antagonist) reduced outflow more than formation. Both salbutamol (beta 2-agonist) and butoxamine (beta 2-antagonist) inhibited aqueous humor formation and aqueous humor outflow to an equal extent. It is concluded that the adrenergic mechanism is functioning only slightly, if at all, in affecting the intraocular pressure. On the other hand, receptor binding experiments on iris-ciliary body showed clearly that there are 40-fold and 281-fold differences in binding affinity of D- and L-isomers of timolol and propranolol, respectively. These results indicate that the adrenergic receptor mechanism does exist in the eye tissues but that it does not control intraocular pressure significantly.     

Steroid metabolism in ocular tissues of the rabbit.

The metabolism of cortisol and other steroids was studied in normal untreated rabbit iris-ciliary body and cornea as part of an investigation into the mechanism of glucocorticoid-induced glaucoma. Cortisol is readily converted to the inactive metabolite cortisone by these eye tissues indicating the presence of an 11beta-oxidoreductase system. This reaction is reversible with cortisone being converted to cortisol in the presence of appropriate cofactor. However, due to the absence of a (or as yet undetectable) cortisol-A-ring-reductase system (rate-limiting reaction) the steroid is not irreversibly metabolized to biologically inactive compounds. The 11beta-oxidoreductase system readily converts other C21-11beta-hydroxysteroids, such as corticosterone, to its appropriate C21-11-ketosteroid (11-dehydrocorticosterone). Some C21-steroids lacking the 11-hydroxyl group (11-deoxycortisol, 11-deoxycorticosterone) remain virtually unmetabolized (exception to this was found with progesterone). Evidence of a C21-steroid A-ring reductase system was found only when cortisone and progesterone were used as substrates. However, testosterone a C19 steroid was converted to clearly identifiable A-ring reduced and 17beta-and 3alpha(beta)-oxidoreduced metabolites, thus indicating the presence of testosterone A-ring reductase, 17beta-and 3alpha(beta)-oxidoreductase systems in the eye tissues studied. The presence of a steroid 5alpha(beta)-reductase for some steroids but not for cortisol indicates a distinct substrate specificity for this enzyme system in the eye tissues.     

白介素1β在干眼患者眼表的表达

目的 探讨白介素1β（IL-1β）在干眼患者眼表的表达,及其与干眼症状、体征的相关性,阐明IL-1β在干眼发病中的作用.方法 临床试验研究.选取2012年9月至2013年2月来山西省眼科医院就诊的干眼患者30例（60眼,干眼组）,无干眼症状体征且年龄与性别构成匹配的个体15例（30眼）作为对照组.所有受检者均做如下检测：眼表失衡指数（OSDI）干眼调查问卷、泪液分泌试验（SIT）、泪膜破裂时间（BUT）、角膜荧光素钠染色、结膜丽丝胺绿染色.同时应用印迹细胞法收集所有2组对象球结膜上皮细胞,分别进行免疫组化染色,以及实时PCR检测结膜细胞中IL-1β的基因表达.采用独立样本t检验,Spearman相关进行数据分析.结果 干眼组与对照组OSDI评分值分别为24.1±2.2、14.3±1.3;SIT分别为（4.13±1.68）mm、（10.53±0.74） mm;BUT分别为（4.17±1.10）s、（8.80±1.21）s;角膜荧光素钠染色评分值分别为4.3±1.5、0.6±0.5;结膜丽丝胺绿染色评分值分别为5.7±2.0、1.9±1.4.干眼组与对照组以上5个指标比较差异均有统计学意义（t=22.23、-19.88、-18.20、12.85、9.62,P＜0.05）.干眼组IL-1β相对基因含量为0.65±0.37,对照组为0.22±0.06,二者比较差异有统计学意义（t=6.31,P＜0.05）.干眼组IL-1β在结膜上皮细胞中的表达与OSDI评分、角膜荧光素钠染色评分、结膜丽丝胺绿染色评分呈正相关（r=0.81、0.58、0.48,P＜0.05）,与SIT、BUT结果呈负相关（r=-0.43、-0.45,P＜0.05）.通过免疫组化法染色,在干眼患者结膜细胞中可见棕褐色颗粒,而在正常人群中未见棕褐色颗粒.结论 IL-1β作为炎性介质不仅参与了干眼的发病,与干眼的严重程度相关,同时也引起了眼表的损害.     

BMP4对眼部细胞调控作用的研究进展

骨形态发生蛋白(bone morphogenetic proteins,BMPs)属转化生长因子β(transforming growth factor-β,TGF-β)超家族成员,是1965年由Urist等首先从脱钙骨基质提取物中分离得到的一种具有独特异位骨和软骨诱导活性的酸性蛋白质.BMP4作为BMPs家族成员之一,不仅促进软骨细胞的分化和发育,还对眼部细胞起着重要的调控作用,其在角膜上皮细胞、角膜细胞和角膜内皮细胞中表达,可以介导视网膜血管内皮细胞的凋亡并抑制血管的生成,且对角膜上皮细胞的发育起着重要作用等.本文总结近年来BMP4在眼部组织的研究进展,对BMP4在眼不同发育阶段的功能情况做一简要综述.     

Challenges in the management of ocular snake-bite injuries

Ocular snake-bite injuries are quite rare away from natural habitats. However, when exotic animals are kept in captivity, the injuries sustained and their management can pose challenges when they present to their local eye department. This report describes an atypical eye injury inflicted by a python and its successful management involving surgical, laser and medical interventions. The case highlights the possible pitfalls resulting from the unusual mechanism of injury and the steps to avoid them. The article goes on to discuss the background of the injuries that can be caused by venomous and non-venomous snakes.     

Antibioprophylaxis in ocular surgery: AFSSAPS recommendations

According to the literature and to the advice of experts, the French Agency for the Safety of Health Products (AFSSAPS) edited recommendations about the antibioprophylaxis in ocular surgery. One goal was to avoid the extensive use of oral and topical fluoroquinolones in antibioprophylaxis, in order to preserve their antibacterial activity for curative treatments of severe eye infections. The medical team decides for the indication and the type of antibioprophylaxis for each patient. A topical antibiotic is recommended for any eye surgery until the etancheity of incisions. Due to the risk of selection of bacterial resistance topical fluoroquinolones are not recommended in this indication. In open eye surgery, an additional antibioprophylaxis is recommended: in cataract surgery, injection in the anterior chamber at the end of the procedure of 1mg of cefuroxime; in other open eye surgeries, only in case of risk factors for endophthalmitis, administration of 500 mg oral levofloxacin tablet 12 hours and two hours before surgery. For ocular punctures and intravitreal injections, only a topical postoperative antibiotic is recommended until healing.     

Experimental dry eye stimulates production of inflammatory cytokines and MMP-9 and activates MAPK signaling pathways on the ocular surface

PURPOSE: To evaluate whether experimentally induced dry eye in mice activates mitogen-activated protein kinase (MAPK) signaling pathways, c-Jun N-terminal kinases (JNK), extracellular-regulated kinases (ERK), and p38 and stimulates ocular surface inflammation. METHODS: 129SvEv/CD-1 mixed mice aged 6 to 8 weeks were treated with systemic scopolamine and exposure to an air draft for different lengths of time, from 4 hours to 10 days. Untreated mice were used as the control. The concentrations of IL-1beta and TNF-alpha in tear fluid washings and in corneal and conjunctival epithelia were measured by ELISA. MMP-9 in tear washings was evaluated by zymography, and gelatinase activity in the cornea and conjunctiva was determined by in situ zymography. Corneal and conjunctival epithelia were lysed in RIPA buffer for Western blot with MAPK antibodies, or they were lysed in 4 M guanidium thiocyanate solution for extraction of total RNA, which was used to determine gene expression by semiquantitative RT-PCR, real-time PCR, and gene array. RESULTS: Compared with those in age-matched control subjects, the concentrations of IL-1beta and MMP-9 in tear fluid washings and the concentrations of IL-1beta and TNF-alpha and gelatinolytic activity in the corneal and conjunctival epithelia were significantly increased in mice receiving treatments to induce dry eye after 5 or 10 days. The expression of IL-1beta, TNF-alpha, and MMP-9 mRNA by the corneal and conjunctival epithelia was also stimulated in mice treated for 5 or 10 days. The levels of phosphorylated JNK1/2, ERK1/2, and p38 MAPKs in the corneal and conjunctival epithelia were markedly increased as early as 4 hours after treatment, and they remained elevated up to 5 days. CONCLUSIONS: Experimental dry eye stimulates expression and production of IL-1beta, TNF-alpha, and MMP-9 and activates MAPK signaling pathways on the ocular surface. MAPKs are known to stimulate the production of inflammatory cytokines and MMPs, and they could play an important role in the induction of these factors that have been implicated in the pathogenesis of dry eye disease.