| Autor: |
WIJDEVELD, M. M. G., KOERTEN, H. K., ONDERWATER, J. J. M., PARROTT, D. T., BOUWSTRA, J. A. |
| Zdroj: |
Journal of Microscopy; Sep1996, Vol. 183 Issue 3, p223-230, 8p |
| Abstrakt: |
The skin acts as an effective barrier to protect the body against penetration of substances from the environment and against desiccation. The main barrier function resides in the stratum corneum, and more specifically in the intercellular lipid domains. Several techniques have been used to elucidate the local lipid crystal arrangements in these domains, but they either needed an extensive pretreatment of the skin with the risk of damaging the native structure, or were not suited to obtain local structure information as bulk quantities of stratum corneum were required. In this paper a method of performing local structure analysis (electron diffraction) on cryo-fixed specimens is described. Therefore a cold chain procedure was used to obtain cryosections of stratum corneum. On these sections visualization and electron diffraction at low temperature were carried out. Using a so-called tape sandwich method, cryosections were prepared in which corneocytes and lipid matrix could easily be distinguished. Moreover, detailed cellular components such as desmosomes and intracellular lipid domains were observed. However, probably due to the limited amount of intercellular lipids in the stratum corneum, electron diffraction on cryosections did not result in diffraction patterns that were undoubtedly originating from the intercellular lipids. In the electron diffraction patterns of a skin lipid model system reflections were present that were indicative of hexagonal and orthorhombic sublattices. The d-spacings of these reflections were similar to the spacings of the high-intensity reflections of the X-ray diffraction pattern of the same mixture. This showed agreement between a bulk and a local technique, X-ray and electron diffraction. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
Plný text