The effect of single and repeated UVB radiation on rabbit lens

Background In our previous investigations, a significant cumulative effect of ultraviolet radiation (UVR) on the corneal and aqueous humour metabolic profiles was revealed. The purpose of the present study was to monitor the alterations in the rabbit lenses under the same experimental design and thereby supplement and complete prior findings. Methods Albino rabbit eyes were exposed to single (312 nm, 3.12 J/cm²) or repeated (312 nm, 3 × 1.04 J/cm²) UVB irradiations of the same overall doses. Lenticular samples were analysed by high resolution magic angle spinning proton nuclear magnetic resonance (HR-MAS ¹H NMR) spectroscopy. Special grouping patterns between the UVB-irradiated and untreated control samples were evaluated using principal component analysis (PCA). Percentage alterations in the lenticular metabolite concentrations from UVR-B exposed rabbits were calculated relative to the levels in the control group. Results UVB irradiation of the albino rabbit lenses resulted in a significant decrease in the concentrations of antioxidants (glutathione), osmolytes (taurine, myoinositol) and amino acids (alanine), and a concomitant elevation in the contents of a sugar-related compound, sorbitol. Repeated UVR-B exposure of the rabbit eye had a stronger effect on the lenticular metabolic profile than a single irradiation of the same overall dose. Conclusions This study reveals the cumulative effect of repeated UVB irradiations, and shows that even a 48-hour interval between subsequent UVR-B exposures is not sufficient for the healing processes to restore lenticular integrity.     

Changes in aqueous humour following single or repeated UVB irradiation of rabbit cornea

Background Aqueous humour is the main nutritive source for corneal and lenticular tissues, and knowledge of a possible cumulative effect of ultraviolet radiation (UVR) on its metabolic profile might be of great help in the assessment of cataract risks. By using high-resolution ¹H nuclear magnetic resonance (NMR) spectroscopy, it was possible to evaluate the effect of a single and repeated UVB radiation of the rabbit eye with the same overall dose on the aqueous humour. Methods Samples of aqueous humour from twenty-four albino white rabbit eyes were examined for the effects of UVB exposure (312 nm). In the first group (UVB1), four animals were irradiated with a single dose 3.12 J/cm² (21 minutes) of UVB radiation. The animals in the second group (UVB2, n = 4) were irradiated three times for 7 minutes every 2nd day (dose of 1.04 J/cm²; days 1, 3, 5) to give the same overall dose (3.12 J/cm²). The third group (n = 4) served as an untreated control group. ¹H NMR spectra of aqueous humour from all eyes were obtained. Special grouping patterns among the tissue samples and relative percentage changes in particular metabolite concentrations were evaluated using appropriate statistical methods (multivariate analysis, Independent sample t-test). Results Significant alterations in the metabolic profile of aqueous humour from UVR-B exposed rabbit eyes and an apparent cumulative effect of repeated UVB irradiation were observed. Conclusions Application of a Carr-Purcell-Meiboom-Gill spin echo pulse sequence was found to have a great advantage for correct analysis of the results obtained with NMR spectroscopy of aqueous humour from eyes where increase of protein level due to an inflammatory process could not be excluded. Grants were received from: The Norwegian Quota Program The Faculty of Medicine, Norwegian University of Science and Technology The Norwegian Research Council The Grant Agency of the Czech Republic No. 304/06/1379 The Academy of Sciences of the Czech Republic AVOZ50390512.     

紫外线诱导晶状体上皮细胞凋亡的实验研究

目的 探讨紫外线对体外培养的牛眼晶状体上皮细胞凋亡作用。方法 以TUNEL技术和DNA片段分析法研究紫外线照射牛晶状体后不同时间晶状体上皮细胞发生凋亡的情况。结果 经紫外线照射后,TUNEL法显示,照射组晶状体上皮细胞中有凋亡细胞,对照组晶状体上皮细胞中无明显的凋亡细胞;DNA片段分析发现照射组晶状体上皮细胞有DNA“梯状”图谱,而对照组晶状体上皮细胞未见DNA断裂现象。结论 紫外线可诱导牛晶状体上皮细胞发生凋亡。     

低剂量辐射对晶体损伤的调查分析

本文对绵阳市351名医用X线工作者的晶体进行了流行病学调查,同时调查了159名不接触X射线的医务工作者、干部、工人作为对照.结果,调查组晶体浑浊的发病率是随着工龄的增长、累计剂量的增高而增高.晶体后皮质浑浊率与对照组比较,有非常显著性差异.晶体浑浊主要是点状、尘状及空泡等改变.本次调查,多数晶体浑浊均属初级阶段.     

长期小剂量电离辐射对晶状体损伤的远后效应

目的　探讨长期小剂量电离辐射对晶状体损伤的远后效应。方法　通过对 68例 (13 6眼 )近 3 0年受小剂量电离辐射晶状体远后效应的观察 ,并与 80例 (160眼 )相近年龄不接触有害因素人员进行对照。结果　对照组与受照组工作人员的晶状体核及皮质浑浊总发生率差异无显著意义 (P >0 .0 5 ) ,而受照组晶状体后囊浑浊的发生率高于对照组 ,差异有非常显著意义 (P <0 .0 1) ,但与累积剂量大小和工龄未发现平行关系。结论　尽管长期小剂量电离辐射对晶状体后囊浑浊改变表现为非特异性变化 ,与对照组比较有明显差异     

The effect of neurotransmitters on rabbit cornea]

PURPOSE: To ascertain the effect of neurotransmitters added to the culture medium of rabbit corneal epithelium and stromal cells. METHOD: The corneal epithelium and stromal cells were cultured in RCGM medium. Three neurotransmitters were added to the medium : substance P, acetylcholine, and vasoactive-intestinal peptide (VIP). RESULTS: Proliferation of epithelial cells significantly increased after incubation for 24 hours with substance P (p < 0.05). There was no change in proliferation after addition of acetylcholine or VIP. The extension of epithelial cell layer increased after addition of substance P but not after addition of acetylcholine or VIP. No change was induced in proliferation of stromal cells or extension of the stromal cell layer after addition of any one of the three substances. CONCLUSION: Substance P stimulates the proliferation of corneal epithelial cells when added to the culture medium.     

The reepithelialization of rabbit cornea following single and multiple denudation

The reepithelialization of rabbit corneas completely denuded once by abrasion with a dental stone was compared with the rate of reepithelialization of the contralateral eye following repeated but gentle repeeling of the epithelium at 2-day intervals for 6 days after an initial complete denudation by abrasion. Two or three times repeeled corneas showed a more rapid initial reepithelialization than observed after the first denudation. Polymorphonuclear leukocytes (PMNs) were found in the corneal stroma and tear fluid following both single and repeated denudation, but only up to 24 hours after the first, more traumatic, denudation were large numbers of PMNs found adherent to the exposed basement membrane of the corneal epithelium. It was hypothesized that PMNs on the corneal surface may interfere with reepithelialization.     

The effect of ultraviolet radiation on choroidal melanocytes and melanoma cell lines: cell survival and matrix metalloproteinase production

Background Ultraviolet radiation (UVR) can induce DNA damage and regulate the expression of factors important for tumour growth and metastasis, including matrix metalloproteinases (MMPs). Epidemiological studies suggest that chronic UVR exposure, especially during early adulthood, may be a risk factor in patients with choroidal melanoma. However, the effects of UV(R)-B on human choroidal melanocyte survival and growth are unknown. In this study, we investigated if UV(R)-B affected the in vitro survival, growth and MMP production of choroidal melanocytes and melanoma cells. Methods Cultures of primary choroidal melanocytes and melanoma cell lines (OCM-1 and OCM-8) were exposed to UV(R)-B (0–30 mJ/cm²). The cell morphology and growth were examined, and cell viability was assessed using an MTT assay. Gelatin zymography was used to assess the enzymatic activity for MMP-2 and -9 in conditioned media following UV(R)-B treatment. Results UV(R)-B ≥20 mJ/cm² was cytotoxic for choroidal melanocytes. Cytotoxic doses of 5 to 10 mJ/cm² were found for OCM-8 and OCM-1 melanoma cell lines. Low levels of UV(R)-B (2.5 and 3.5 mJ/cm²) significantly reduced melanoma cell viability after 48 h, although melanocyte viability was not affected by doses of UV(R)-B <10 mJ/cm². Conditioned media from melanoma cells and melanocytes displayed pro-MMP-2 activity independent of UV(R)-B. Control and UV(R)-B-treated OCM-1 cells secreted active MMP-2 up to 72 h. Pro-MMP-9 activity was seen from 36 h for control and UV(R)-B-treated OCM-1 and OCM-8 cells. Conclusions Melanocytes appeared more resistant to physiological doses of UV(R)-B than melanoma cells; the potential of melanocytes to initially survive DNA damage following UV(R)-B exposure may be relevant to the subsequent transformation of melanocytes to melanomas. Although UV(R)-B did not induce the production and/or activation of MMP-2 and -9 in melanocytes or melanoma cells, we are currently investigating whether DNA damage-response genes such as p53 and p21 can be regulated following UVR exposure, and whether they are important for choroidal melanoma development. This study was supported in part by grants from the Sydney Foundation for Medical Research (MCM) and the National Health and Medical Research Council, Australia (RMC).     

The effect of topical cyclosporin A on the rabbit cornea

To investigate the effect of topical cyclosporin A (CSA) on the rabbit cornea, both eyes of 80 animals were treated with CSA 2% eye drops over a 3-week period under various conditions. CSA was dissolved in castor oil or ethanol 13.8 vol. %. Slit-lamp, scanning and transmission electron microscopic examinations were performed. CSA 2% in castor oil given 5 times daily showed no damage to either the corneal epithelium or endothelium. In contrast the solutions containing ethanol revealed considerable epithelial cell damage.Presented at the meeting of the Northwest German Society of Ophthalmology (Nordwestdeutsche Augenarzte), Hamburg, FRG, 2 June, 1985     

视路肿瘤的磁共振表现特点及对视功能的影响

目的 探讨视路系统常见肿瘤的磁共振（magnetic resonance imaging，MRI）表现特点及对视功能影响的关系。 方法 回顾性分析119例经手术与病理证实的视路系统肿瘤的MRI资料。其中视路前段肿瘤36例，视路中段肿瘤70例，视路后段肿瘤13例。MRI检查，自旋回波横轴位T-1WI(spine echo,SE),横轴位及冠状位快速自旋回波T-2WI(turbo spine echo,TSE)，冠状位频率敏感脂肪抑制T-2WI(spectral saturation inversion recovery,SPIR)，及二乙烯三胺五乙酸铵(gadoliniam diethylene triamine pentaacetic acid,Gd-DTPA)增强后的横轴位、矢状位及冠状位T-1WI SE。 结果 视路系统肿瘤，包括原发于视路的肿瘤（如视网膜母细胞瘤、神经胶质瘤、神经母细胞瘤等）与侵犯视路的肿瘤（如眼眶囊肿、鼻咽癌、垂体瘤、脑膜瘤、颅内转移瘤等）。视路各部位肿瘤的 MRI成像各有其特点，以脑垂体瘤最为常见，且对视功能影响较为明显。 结论 MRI是视路肿瘤早期诊断的有效方法。 (中华眼底病杂志, 2002, 18: 101-103)     

核心蛋白多糖对兔晶状体上皮细胞增生的抑制作用

背景 研究发现,白内障囊外摘出术后组织修复反应可诱导房水中活性转化生长因子β(TGF-β)的增加,残留的晶状体上皮细胞(LECs)移行、分化,细胞外基质沉积,引起上皮-间质转化,导致后囊膜混浊(PCO)的发生.寻求有效的抑制LECs增生的药物对于临床上防治PCO的发生具有重要意义. 目的 探讨核心蛋白多糖( decorin)对兔LECs增生的抑制作用及其剂量-效应与时间-效应的关系. 方法 兔LECs细胞株进行培养和传代,将处于指数生长期的细胞以8×106个/L密度接种于96孔板,将0.1、1.0、10.0 mg/Ldecorin分别加入培养基中培养24、48、72 h,加入体积分数0.1％ DMSO培养的细胞为阳性对照组,常规培养基培养的细胞为空白对照组.MTT比色法分别测定不同质量浓度的decorin作用于LECs不同时间后的细胞生长抑制率;采用流式细胞技术测定各组细胞的细胞周期,用ELISA法检测各组培养液上清中TGF-β的水平,逆转录聚合酶链反应(RT-PCR)法测定TGF-βmRNA在LECs中的表达,免疫细胞化学法观察α-平滑肌肌动蛋白(α-SMA)的表达.结果 ELISA检测结果表明,各组培养基上清液中TGF-β表达量的差异有统计学意义(F=39.24,P=0.03),不同质量浓度组TGF-β水平均明显低于空白对照组,差异有统计学意义(P＜0.01),1.0 mg/L、10.0 mg/L decorin组TGF-β水平均明显低于0.1 mg/L decorin组(P＜0.05).MTT比色法结果显示,≥1.0 mg/L decorin组LECs增生的抑制率明显高于空白对照组,各质量浓度decorin组药物作用48 h和72 h后LECs增生的抑制率明显高于24 h的值,药物作用72 h后LECs增生的抑制率明显高于48 h的值,差异均有统计学意义(P＜0.05),各质量浓度decorin组G0/G1期LECs所占比例均较空白对照组明显增加,差异均有统计学意义(P＜0.05).RT-PCR检测显示,TGF-β mRNA的表达随着decorin质量浓度的升高而降低.免疫组织化学染色表明,10.0 mg/L decorin组α-SMA在LECs中的表达明显弱于空白对照组. 结论 Decorin可以抑制LECs的增生,也可以诱导LECs凋亡,其效应呈明显的剂量和时间依赖性,有望成为最具潜力的防治PCO的药物之一.     

The protective effect of alpha-lipoic acid against oxidative damage in rabbit conjunctiva and cornea exposed to ultraviolet radiation

PURPOSE: The purpose of this study was to determine the protective effect of alpha-lipoic acid against oxidative damage in rabbit conjunctiva and cornea exposed to ultraviolet radiation. METHODS: 20 rabbits weighing 2,500- 3,000 g were used, and we divided them into 4 groups with 5 randomly selected rabbits. The rabbits were exposed to 2 J/cm(2)/h of ultraviolet A radiation (UVA) in the range of 320-405 nm for 12 h per day within 90 days. The control group did not undergo any procedure, the UVA group was only exposed to UVA radiation. The PUVA group was treated with 8-methoxypsoralen and UVA. The alpha-lipoic acid group was administered 8-methoxypsoralen + UVA + alpha-lipoic acid. At the end of 90 days, the rabbits were killed by decapitation, and the eyes were enucleated. Both eyes of each rabbit were used for biochemical evaluation. Conjunctival and corneal free malondialdehyde (MDA), glutathione peroxidase (GSH-PX) and superoxide dismutase (SOD) levels were compared among the groups. RESULTS: Conjunctival free MDA levels were lower in the alpha-lipoic acid group compared with the UVA and PUVA groups (p < 0.05, p < 0.001, respectively). Both conjunctival SOD levels (p < 0.05, p < 0.01, respectively) and conjunctival GSH-PX levels (p < 0.01, p < 0.001, respectively) were higher in the alpha-lipoic acid group compared with other groups. Corneal free MDA levels were lower in the alpha-lipoic acid group compared with the UVA and PUVA groups (p < 0.01, p < 0.001, respectively). Both corneal SOD levels (p < 0.01, p < 0.01, respectively) and corneal GSH-PX levels (p < 0.01, p < 0.01, respectively) were higher in the alpha-lipoic acid group compared with the other groups. CONCLUSION: alpha-Lipoic acid which is considered as potent antioxidant protects the eye from the damaging effect of ultraviolet exposure.     

Ciliary body PDT in pigmented rabbit eyes: effect of single and repeated treatment

PURPOSE. To investigate the morphologic and hypotensive effect of contact transscleral ciliary body PDT in pigmented rabbit eyes. METHODS. The right eyes of 33 pigmented rabbits were irradiated using chloraluminum sulfonated phthalocyanine as photosensitizer and a diode laser (670 nm) as the light source. Twenty-five animals received a single treatment. Eight animals received a second treatment 13 days after the first one. Photosensitizer was administered by means of continuous intravenous infusion. Ciliary body was irradiated transsclerally by means of an optic fiber applied on the corneoscleral limbus. In all cases 14-16 laser applications were performed to cover 360 degrees of the ciliary body. Animals were followed for a maximum of 30 days by means of tonometry and biomicroscopy. Retreatments were performed using the same irradiation protocol. At the end of the follow up time animals were sacrificed and their were eyes prepared for light and electron microscopy. RESULTS. Transscleral ciliary body PDT resulted in significant but temporary reduction of IOP in all cases. The effect lasted about two weeks. Retreatment led to a new significant drop of the IOP, which lasted about two weeks again. In histological examination the initial effect was vascular thrombosis, followed by edema and disintegration of the ciliary epithelial layers. In all cases the appearance of the ciliary body had returned to normal 15 days after irradiation. CONCLUSION. Contact transscleral PDT with the treatment parameters used in this study results in significant but temporary functional and morphological alteration in pigmented rabbits ciliary body.     

Ho：YAG激光角膜热成形术对兔眼组织的生物效应

本文使用波长为２．１μｍ的Ｈｏ：ＹＡＧ激光对兔眼周边部角膜行激光角膜热成形术（Ｌａｓｅｒｔｈｅｒｍｏｋｅｒａｔｏｐｌａｓｙ，即ＬＴＫ），采用不同激光能量和脉冲数通过裂隙灯显微镜、光镜以及扫描、透射电镜观察术后不同时间兔角膜的生物学反应特征，证实ＬＴＫ术为安全、有效的术式，以７８Ｊ／ｃｍ２能量密度、２个脉冲、１０Ｈｚ频率，光凝角膜深度可达角膜厚度７７％。     

The effect of timolol,betaxolol and levobunolol on the surface of rabbit cornea

Pigmented rabbits were treated with timolol maleate, betaxolol hydrochloride or levobunolol hydrochloride eye drops twice a day for six months. Animals of the same age group and breed were used as controls. There were no differences observed in corneal epithelium with light and transmission electron microscopy. With scanning electron microscopy, in the timolol and betaxolol treated animals the picture of the corneal surface was similar to that of normal rabbit corneas after exposure to air. In scanning electron micrographs of the levobunolol treated animals, the corneal surface resembled the corneas of normal rabbits treated with artificial tears.     

RGDRGD肽对人晶状体上皮细胞黏附与增生作用的影响

背景RGD肽是一类含有精氨酸-甘氨酸-天冬氨酸的小分子多肽,其在抑制肿瘤细胞黏附、转移和肿瘤新生血管的生成中起重要作用。研究证实RGD肽能够抑制晶状体上皮细胞（LECs）的黏附和增生,RGDRGD肽串联起来作用增强。目的研究RGDRGD肽对体外培养的人LECs黏附与增生的影响,并与RGD肽的作用进行比较。方法将在体外分离培养的LECs中分别加入250、500、1000mg／L的RGDRGD肽和RGD肽作为实验组,仅加入细胞培养液作为对照组。将LECs以2×10。／ml密度接种到含有纤维连接蛋白（FN）和I型胶原蛋白预孵化的96孔培养板中,培养1h后用MTT比色法检测RGDRGD肽与RGD肽对细胞黏附率的影响。将LECs接种于培养板,分别加入250、500、1000、2000mg／L的RGDRGD肽和RGD肽培养24、48、72h,检测RGDRGD肽和RGD肽对LECs增生的影响。结果RGDRGD肽对人LECs黏附率的抑制呈明显的剂量依赖性,随着其质量浓度的增加,对细胞黏附的抑制作用越强,500mg／L的RGDRGD肽比RGD肽抑制人LECs黏附的作用更强（P〈0．01）。RGDRGD肽对人LECs增生的抑制呈明显的时间剂量依赖性,1000mg／L的RGDRGD肽作用48h比RGD肽对人LECs增生的抑制作用更强（P〈0．01）。结论RGDRGD肽抑制LECs黏附与增生的作用强于RGD肽,为进一步临床应用提供了理论依据。     

The effect of benzalkonium chloride on the electropotential of the rabbit cornea.

The effect of benzalkonium chloride on the electropotenial of the cornea has been examined. The anterior surface of the in vivo or in vitro cornea was exposed to various concentrations of the surfactant, from 0.005% to 0.02%, for either 1 or 2 min. The initial effect is a hyperpolarization lasting up to 30 sec, followed by a rapid fall in potential difference with a subsequent recovery. The degree of potential difference decrease and the recovery rate was dependent upon both the concentration of the detergent, and the exposure time. There is excellent correlation between the previous anatomical and physiological studies on tracer penetration across the in vivo and in vitro cornea and our present work. The data indicate that benzalkonium chloride acts by breaking down the physiological and anatomical diffusion barrier to solute and solvent which is located in the outer layer of the epithelium.     

电磁辐射对家兔视觉器官组织结构的影响

目的探讨电磁辐射对家兔眼球组织特别是视网膜即刻损伤的生物学效应。方法青紫蓝大灰兔32只，共64眼，随机分为4组，除似性辐射对照组外，A、B、c3组为辐照组，辐射波长为3cm。其它的暴露条件分别是，A组：峰值功率密度60W／cm^2，辐射时间15min，距离0．9m组；B组：峰值功率密度90W／cm^2，辐射时间15min、距离0．7m组；C组：峰值功率密度90W／cm^2，辐射时间30min、距离0．7m组。采用高功率电磁波直接辐照家兔全身，于辐照后即刻取材，随后包埋固定，分别在光镜和电镜下观察其眼的组织结构。结果不同剂量辐照后，各组家兔视网膜的组织结构均比对照组有不同程度改变，在c组的改变明娃严重于对照组和其他各组，B组和A组的组织结构损伤程度大致相同，视网膜的组织结构损伤程度与辐照剂量和照射时间有关。结论高场强的电磁波暴露可造成家兔眼视网膜组织的即刻损伤，对家兔视觉组织器官的组织结构可产生明显的损伤作用，其作用强度与辐照剂量和暴露时间存在一定的量效、时效关系。     

紫外线对人晶状体上皮细胞端粒酶活性和氧化损伤蛋白表达水平的影响

目的　探讨在紫外线诱导的人晶状体上皮细胞DNA损伤修复过程中端粒酶活性和氧化损伤蛋白的变化和作用。方法　采用照射剂量为0 0(对照组)及0 .5、1. 5、2 .5、3 .5、5 .0、7 .5、10 0mJ/cm2 (实验1~7组)的紫外线照射人晶状体上皮细胞,采用端粒酶重复序列扩增酶联免疫吸附测定法检测端粒酶活性,采用免疫印迹法检测p53、DNA损伤诱导生长停顿基因(GADD45)、增殖细胞核抗原(PCNA)及细胞周期依赖激酶抑制剂p16的蛋白表达水平。结果　对照组和实验1~7组的端粒酶活性呈上调趋势, 8组比较差异有统计学意义(F=45. 65,P<0 .01 );对照组和实验1 ~7组的p53、GADD45、PCNA、p16的蛋白表达水平均呈上升趋势, 8组比较差异均有统计学意义(F=13 .015 52, 41 241 .40, 25. 084 19, 44 331 .72;P<0. 01)。结论　在紫外线诱导的人晶状体上皮细胞DNA损伤修复过程中,端粒酶活性上调,氧化损伤蛋白的表达水平上升。端粒酶活性的上调既加强了保护细胞的作用,又增强了增殖作用;氧化损伤蛋白表达水平的提高在紫外线诱导的人晶状体上皮细胞DNA损伤修复过程中发挥关键作用;端粒酶活性上调与氧化损伤蛋白表达水平提高有关。