ENVIRONMENTAL UV EFFECT ON MAMMALIAN SKIN

这项工作的总体目标是了解光生物学 环境紫外线对哺乳动物皮肤的慢性损伤机制 以足以准确地解释和预测 持续臭氧消耗对慢性阻塞性肺疾病的光生物学影响 表皮和真皮损伤，包括光致癌和 “光老化。”观察到的作用谱具有剂量和时间依赖性。 (“动态”)，主要是由于紫外线诱导的增殖。对此进行更正 Effect允许构建可以 与各种太阳光谱分布(包括 模拟平流层臭氧消耗引起的变化)以提供 各种大气条件下的“生物有效剂量”。 具体地说，我们希望(L)将正在进行的光生物学研究扩大到 SK-1无毛小鼠包括临床、组织学和生化 作为总剂量、波长和剂量传递的函数的响应。我们 将监测紫外线诱导的嘧啶二聚体、酸的增加 糖胺多聚糖(GAG)，以及胶原结构和 荧光特性。(2)构建紫外光诱导DNA的作用光谱 和皮肤损伤。这些将被“修正”为非均匀吸收。 惰性角质层-表皮入射辐射，以提供 “本征”作用谱。(3)比较宽幅与窄幅的效果 波段辐射对上述剂量-效应和作用谱的影响 (测试UVA/UVB波段相互作用)。除了提供 基础光化学和生化信息，机理 这些研究提供的洞察力应该能够更准确地解释 以及臭氧消耗或其他因素的光生物学后果的预测 大气变化会改变太阳紫外线在地球上的数量 环境。

The overall objective of this work is to understand the photobiological mechanisms involved in chronic environmental UV damage to mammalian skin in a manner sufficient to accurately explain and predict the photobiological consequences of on-going ozone depletion on chronic epidermal and dermal damage, including photocarcinogenesis and "photoaging." Observed action spectra are dose- and time-dependent ("dynamic"), mainly due to UV-induced hyperplasia. Correction for this effect allows construction of "intrinsic" action spectra that can be convoluted with various solar spectral distributions (including those which simulate changes due to stratospheric ozone depletion) to afford "biologically effective doses" under the various atmospheric conditions. Specifically, we wish to (l) expand ongoing photobiological studies in Sk-1 hairless mice to include clinical, histological, and biochemical responses as a function of total dose, wavelength, and dose delivery. We will monitor UV-induced increases in pyrimidine dimers, acid glycosminoglycans (GAG), and changes in collagen structure and fluorescence properties. (2) Construct action spectra for UV-induced DNA and dermal damages. These will be "corrected" for non-uniform absorption of incident radiation by inert stratum corneum-epidermis, to afford "intrinsic" action spectra. (3) Compare the effect of broad- vs. narrow band radiation on the dose-response and action spectra obtained above (test for UVA/UVB waveband interactions). In addition to providing fundamental photochemical and biochemical information, the mechanistic insight provided by these studies should enable more accurate explanation and prediction of photobiological consequences of ozone depletion or other atmospheric changes which would alter the amount of solar UV in the environment.