Phytomedicines Prepared from Arnica Flowers Inhibit the Transcription Factors AP-1 and NF-κB and Modulate the Activity of MMP1 and MMP13 in Human and Bovine Chondrocytes - Jäger, Christoph; Hrenn, Andrea; Zwingmann, Jörn; Suter, Andreas; Merfort, Irmgard (Planta Medica, 2009)