PHOTOBIOLOGY OF THE LENS

描述（研究者摘要）：近紫外光 众所周知，阳光会增加人类皮层形成的风险， 白内障 不同波长的近紫外光的作用机制 透镜上的辐射目前是未知的。 本研究的重点是 量化特定波长的生物有效性， 在所述透镜和透镜构件上的297和400 nm之间的辐射。行动 紫外线B波段单色光致透镜混浊光谱 将在生物学条件下测定UVA（297 - 320 nm）和UVA（320 - 400 nm）。 有意义的条件。 完整的牛和人晶状体和匀浆将 被利用 光谱技术和蛋白质交联将用于 评估损失。 对产生特异性抗体的定量研究 活性氧物种将做，以评估其在光损伤中的作用 在不同的波长。不到10%的UVB和60%的 UVA在体内到达人透镜上皮。UVB而不是UVA 增加了最近人类皮质性白内障形成的风险 流行病学研究。 UVB和UVA辐射的生物学效应 透镜上皮细胞目前尚不清楚。 定量作用谱 对细胞存活、新合成蛋白质的合成以及 本研究计划在透镜上皮细胞中进行DNA损伤。 这些数据 将提供近紫外线生物效应的定量信息 在上皮上的波长。 不同年龄的正常人晶状体 （婴儿、年轻人和老年人）和白内障的透镜上皮细胞将被 研究确定近紫外辐射的作用机制， 人体内的透镜。 这项建议的长远目标是 定义透镜成分变化的分子机制， 更好地了解光损伤与人类之间的联系 白内障形成。

DESCRIPTION (Investigator's Abstract): Near-ultraviolet light from sunlight is known to increase the risk of formation of human cortical cataracts. The mechanism of action of different wavelengths of near-UV radiation on the lens is unknown at present. The focus of this study is to quantitate the biological effectiveness of specific wavelengths of radiation between 297 and 400 nm on the lens and lens constituents. Action spectra for lens opacification by monochromatic wavelengths in UVB (297-320nm) and UVA (320-400 nm) will be determined under biologically meaningful conditions. Intact bovine and human lenses and homogenates will be used. Spectroscopic techniques and protein crosslinking will be used to assess the damage. Quantitative studies on the generation of specific reactive oxygen species will be done, to assess their role in photodamage at different wavelengths. Less than ten percent of UVB and 60 percent of UVA reaches the human lens epithelium in vivo. However, UVB and not UVA increased the risk of cortical cataract formation in a recent human epidemiological study. The biological effects of UVB and UVA radiation on lens epithelial cells are unknown at present. Quantitative action spectrum studies on the cell survival, synthesis of newly synthesized proteins and DNA damage in lens epithelial cells are planned in this study. These data will provide quantitative information on the biological effects of near-UV wavelengths on the epithelium. Normal human lenses of different ages (infant, young and old), and cataractous lens epithelia will be investigated to determine the mechanism of action of near-UV radiation of the human lens in vivo. The long-term objective of this proposal is to define a molecular mechanism for the changes in lens constituents and obtain a better understanding of the link between photodamage and human cataract formation.