[1] INSERM U128, IFR 24, F-34293 Montpellier 5, France
[2] Acad Sci PRO MED CS Praha AS, Inst Expt Biopharmaceut, Hradec Kralove 50002, Czech Republic
[3] Karl Franzens Univ Graz, Inst Pharmakol & Toxikol, A-8010 Graz, Austria
[4] Univ Strathclyde, Dept Chem, Glasgow GU1 2XH, Lanark, Scotland