Dept. of Nuclear Physics, Lund University, Institute of Science and Technology, Sölvegatan 14, S-223 62, Lund, Sweden.
Biol Trace Elem Res. 1987 Apr;12(1):297-308. doi: 10.1007/BF02796687.
In order to understand the normal and pathological physiologies of the epidermal cells, the simultaneous determination of several elements in the different cellular strata is of crucial importance. In recent years the electron microprobe (EMP) has become an established technique in this field. Its high spatial resolution, in principle, allows measurements of various cell organelles. However, the limited (intrinsic) sensitivity of the EMP represents a serious drawback to the technique. The introduction of the proton microprobe (PMP) has significantly improved the sensitivity, although the ultimate spatial resolution of the PMP is much less than that of the EMP.When studying the elemental profiles in skin epidermis, it is possible to use skin sections with a thickness of the order of 10 μm, then the spatial resolution of the PMP is equal to or better than that of the EMP since the electrons are scattered to a significant degree in the sample. The characteristics of the two methods have been compared by analysis of parallel duplicate freeze-dried sections of normal human skin. The distributions of the elements P, S, Cl, and K, obtained with the two techniques, were in good agreement. In addition, the PMP provided distributions of the important elements Ca, Fe, and Zn.In a recently started study, the useful features of the PMP will be used for studying how efficient a barrier the skin is to nickel and chromate ions. A preliminary experiment has been performed by exposing cadaverous skin, not older than 24-h postmortem, to solutions of the two ions. After an 18-h exposure, samples were prepared by shock-freezing and sectioning. The first results from PMP analysis of these samples demonstrate the presence of a nickel and chromium gradient in the outer strata in the epidermis (mainly stratum corneum).A third experiment deals with the physiology of psoriatic skin. Calcium is an important element in the differentiation. Hence, the higher sensitivity of the PMP has been used in analysis of sections from psoriatic skin epidermis. Preliminary results are presented.
为了理解表皮细胞的正常和病理生理学，同时确定不同细胞层中的几个元素是至关重要的。近年来，电子探针（EMP）已成为该领域的一项成熟技术。其高空间分辨率原则上允许测量各种细胞细胞器。然而，EMP 的有限（固有）灵敏度是该技术的一个严重缺点。质子探针（PMP）的引入显著提高了灵敏度，尽管 PMP 的最终空间分辨率远低于 EMP。在研究皮肤表皮中的元素分布时，可以使用厚度约为 10 μm 的皮肤切片，此时 PMP 的空间分辨率与 EMP 相同或更好，因为电子在样品中会发生显著散射。通过对正常人体皮肤的平行冷冻干燥切片进行分析，比较了两种方法的特性。用两种技术获得的 P、S、Cl 和 K 元素的分布情况非常吻合。此外，PMP 还提供了 Ca、Fe 和 Zn 等重要元素的分布情况。在最近开始的一项研究中，将利用 PMP 的有用特性来研究皮肤对镍和铬酸盐离子的屏障效率。通过将尸检皮肤（不超过死后 24 小时）暴露于两种离子的溶液中，进行了一项初步实验。暴露 18 小时后，通过冲击冷冻和切片制备样品。对这些样品进行 PMP 分析的初步结果表明，在表皮的外层（主要是角质层）存在镍和铬的梯度。第三个实验涉及银屑病皮肤的生理学。钙是分化的重要元素。因此，PMP 的更高灵敏度已用于分析银屑病皮肤表皮的切片。初步结果。
