Abstract: The invention relates to the use of &agr;-lipoic acid in reduced or oxidized form or derivatives thereof with intact dithiolane structure in the form of enantiomers or pharmaceutically acceptable salts, amides, esters, thioesters, ethers or metabolites for the adjuvant therapy of dementias.

Abstract: An arrangement for withdrawing particles of material removed by a working tool of a machine tool during a machining process, comprises a working frame adapted to support a machine tool, casing forming an at least partially closed chamber adapted to surround the working tool so as to accommodate the particles of material removed during machining process, port elements communicating with the chamber and adapted to be connected to a suction source so as to aspirate the particles from the chamber, and mounting elements for mounting the casing on the working frame so that the chamber surrounds the working tool when the machine tool is supported by the working frame.