茶黄素对高糖诱导的人晶状体上皮细胞氧化损伤的影响

研究茶黄素(Theaflavin,TF)对高糖(High glucose,HG)诱导的人晶状体上皮细胞(Human lens epithelial cells,HLECs)氧化损伤的影响。采用体外培养人晶状体上皮细胞,用葡萄糖诱导细胞成氧化损伤模型,外加一定浓度的茶黄素干预,比色法检测细胞体内SOD、CAT、GSH-Px、MDA活力和含量的变化。结果表明相对于正常培养的细胞,高糖诱导细胞体内SOD、CAT、GSH的活性降低,MDA含量上升;加入茶黄素后,提高了细胞内SOD、CAT、GSH-Px的活力,降低了细胞内MDA的含量,与模型组细胞相比,具有显著差异(P0.01)。     

茶黄素对葡萄糖诱导的人晶状体上皮细胞 一氧化氮合成的影响

为探明茶黄素–3,3'–双没食子酸酯(TFDG)对人晶状体上皮细胞SRA01/04(Human lens epithelial cells,HLECs SRA01/04)的保护作用,采用MTT法建立高浓度葡萄糖(HG)诱导的HLECs损伤模型,同时观察HLECs细胞形态的变化。用不同浓度(4、8、16、64、32、64、128、256、512μmol/L)TFDG处理HLECs损伤细胞,采用化学比色法和硝酸还原法测定HLECs内一氧化氮(NO)的含量和一氧化氮合酶(NOS)的活性。结果表明:高浓度葡萄糖可以抑制人晶状体上皮细胞生长,用于HLECs损伤模型诱导的最佳葡萄糖浓度为50 mmol/L,最佳诱导时间为24 h;与未经处理的模型细胞相比,经浓度为16~64μmol/L TFDG处理的模型细胞的存活率显著提高(P0.05);各个浓度的TFDG能极显著降低模型细胞内NOS的活性,极显著减少NO的合成(P0.01),且呈浓度依赖性。以上结果表明,TFDG对高浓度葡萄糖诱导的HLECs细胞损伤具有较好的保护作用。     

Posterior lens luxation with associated glaucoma in a pony

Secondary lens luxation is an infrequent consequence of equine recurrent uveitis (ERU). This Case Report describes a pony with posterior lens luxation with associated glaucoma, thought to be secondary to ERU.     

Matric Suction Effect on Shear Strength of Roadbed Unsaturated Soil

A study which focuses on the role of matric suction in the stress strength of roadbed unsaturated soil was presented. Two types of tests were described, namely, the suction controlled shear test and microstructure scanned test. For the former, four sub tests were conducted under different suction and net normal stress conditions. And two unsaturated soil samples that belong to the same type but with different water contents were scanned. In contrast with clay soil, the corresponding results show that the strength of silty sand soil does not always increase as matric suction increases or soil water content decreases; there exists a peak contributed by matric suction that acts on soil stress strength. The main reason for this kind of phenomenon is due to the typical microstructure of this type of soil and the various types of pore water retention. Additionally, the state of stress in which soil sample meets can also exerts important influence on soil strength.     

A pilot study on the corneal curvatures and ocular dimensions of horses less than one year of age

Intraocular lenses (IOLs) have been implanted in adult equine eyes after cataract surgery. Foals and weanlings comprise a large proportion of those horses undergoing cataract surgery. Due to potential differences in the size and corneal curvature of the juvenile eye, it is not currently known whether implantation of adult IOLs is appropriate in foals and weanlings. The objective of the study was to measure the anterior chamber depth (ACD), central lens thickness (CLT), vitreous chamber depth (VCD), axial globe length (AGL) and corneal curvature of horses less than one year of age. The axial dimensions from one eye of 10 foals were measured using simultaneous A and B scan ultrasonography. The corneal curvature from one eye of 7 weanlings was determined using a modified photokeratometer. Ultrasonography revealed a mean ACD of 4.94 mm, mean CLT of 9.38 mm, mean VCD of 18.96 mm and mean AGL of 33.32 mm for the foals. The mean corneal curvature was 15.4 diopters (D). The mean ACD, CLT, VCD and AGL of the foals were less than the measurements reported in the literature for adult horses. The mean corneal curvature was similar to the values reported by some authors for adult horses. Due to the differences in axial dimensions between adult and juvenile eyes, an IOL that corrects vision in an adult horse might not adequately correct vision in a horse less than one year of age.     

测量X光透镜扭曲度实验方法的建立

扭曲度的大小是反映透镜质量的重要参数。通过测定不同透镜的峰位分布曲线和选用不同的光阑测定不同透镜的扭曲度,得知光阑越接近X光透镜的边缘,衍射光的峰位变化越大;选用光阑越大则测得的扭曲度越大。扫描速度定为0.125°／min重复性很好,建立了测量X光透镜扭曲度的实验方法。     

Examination of the rat eye at the early stage of development with osmium tetroxide staining

This communication describes the benefit of osmium tetroxide (OsO4) staining on the examination of the eye during the early stage of organogenesis of rat embryos. The embryos were obtained by laparotomy on embryonic day 12 (ED 12) and were stained with OsO4 for examination of the ocular tissues with a binocular stereo-microscope, light microscope and scanning electron microscope. At the binocular stereo-microscopic level, the invaginated lens placode, lens pit and optic cup were clearly distinguished. The osmium-stained lens placode and the optic cup were light brown and dark brown in color, respectively. Light microscopic examination revealed that OsO4 postfixation could provide superior paraffin-embedded embryonic sections. Scanning electron microscopic examination revealed the lens pit as a round opening between the lateral nasal prominence and maxillary prominence. Thus, a rapid technique by which the ocular tissues of rat embryos can be examined under a binocular stereo-microscope was developed. This OsO4 staining method will provide a useful tool for research on organogenesis and ocular development.     

Golden Retriever uveitis: 75 cases (1994-1999)

OBJECTIVE: To document the presenting ocular signs and the clinical course of Golden Retriever dogs with a progressive anterior uveitis, often associated with the histologic presence of iridociliary cysts. Animals studied Seventy-five Golden Retriever dogs (142 affected eyes) referred to a private practice referral ophthalmology clinic between 1994 and 1999. Procedures Complete ophthalmic evaluation with slit-lamp biomicroscopy, indirect ophthalmoscopy, applanation tonometry, and gonioscopy. Hematology, serum biochemical evaluations, and serologic titers for endemic infectious agents were also used in selected cases. RESULTS: The age range of affected dogs was 4.5-14.5 years, with a mean age of 8.6 +/- 2.1 years. The majority of the dogs (n = 66) were affected in both eyes at first presentation. The sex distribution included 4 intact males, 32 neutered males, and 39 spayed females. Hematology, serum biochemical evaluations, and serologic titers for endemic infectious agents failed to demonstrate any underlying disorder. The ophthalmic hallmark of this syndrome was the appearance of pigment on the anterior lens capsule, often in a radial orientation. This capsular pigment was seen both with and without associated uveal cysts. Although single to multiple iridociliary cysts were noted clinically in only 13.3% of the cases, cysts were common on histopathology of advanced glaucomatous, blind eyes. Fibrin was observed in the anterior chamber of 37% of the cases, and often was a precursor for glaucoma. Cataract formation (37%) and glaucoma (46%) were frequent sequelae to the uveitis. Posterior synechiae formation occurred in 50% of the cases. Histopathologic analysis of four enucleated eyes and the eviscerated specimens from 14 glaucomatous eyes demonstrated thin-walled iridociliary epithelial cysts in 3/4 and 12/14 cases, respectively. Microscopically, little to no uveal inflammatory infiltration was commonly noted. Conclusion The overall prognosis for this progressive uveitis in Golden Retriever dogs is guarded, with 46% of the eyes becoming blind due to glaucoma. Iridociliary cysts in Golden Retriever dogs may lead to the development of glaucoma in this breed.