1. Nencki Institute of Experimental Biology, Department of Muscle Biochemistry, 3 Pasteur Street, 02-093 Warszawa, Poland.
2. lnstitute of Biochemistry, University of Zürich-Irchel, Winterthurerstrasse 190, CH-8052 Zürich, Switzerland.
3. Department of Pediatrics, Division of Clinical Chemistry, University of Zürich, Steinwiesstrasse 75, CH-8032 Zürich, Switzerland.