1. Goldstein & Lewin technology GmbH. Dept, of Medical Research. Kastanienweg 23, D-14532 Stahnsdorf, Germany
2. Latvian Medical Academy. Dzirciema 16. LV-1007, Riga. Latvia
3. Latvian Institute for Experimental and Clinical Medicine. O. Vaciesa 4. LV-1004 Riga. Latvia