A procedure for the isolation of asbestos bodies from lung tissue by exploiting their magnetic properties: a new approach to asbestos body study.

The role of asbestos bodies (and associated proteinacious coating) in asbestos associated diseases is not well understood. Currently employed methods of isolation of these bodies employ harsh chemicals that lead to destruction of their proteinacious coating. In this work a method was developed that enabled the purification of whole, integral, unmodified asbestos bodies (AB) by exploiting their magnetic properties. Albumin and ferritin were found to be the major proteins associated with AB isolated from lung tissue of mesothelioma patients. Magnetically isolated AB were shown to be cytotoxic and to activate free radical production from inflammatory cells at a higher extent than that induced by bodies obtained by chemical digestion. The finding that hypochlorite-treated AB induce DNA damage, while AB obtained by the method described in this article failed to do so, together with the differential behavior of these bodies toward inflammatory cells, suggests that native asbestos bodies should be used to investigate the pathogenetic role of these structures.

Emission-depth-selective auger photoelectron coincidence spectroscopy.

The collision statistics of the energy dissipation of Auger and photoelectrons emitted from an amorphized Si(100) surface is studied by measuring the Si 2p photoelectron line as well as the first plasmon loss peak in coincidence with the Si-LVV Auger transition and the associated first plasmon loss. The Si 2p plasmon intensity decreases when measured in coincidence with the Si-LVV peak. If measured in coincidence with the Si-LVV plasmon the decrease is significantly smaller. The results agree quantitatively with calculations accounting for surface, volume, and intrinsic losses as well as elastic scattering in a random medium. In this way one can determine the average emission depth of individual electrons by means of Auger photoelectron coincidence spectroscopy, which therefore constitutes a unique tool to investigate interfaces at the nanoscale level.