1. Department of Biochemistry and Molecular Medicine School of Medicine University of California Davis Sacramento CA 95817 USA
2. Division of Pharmaceutical Biosciences Centre for Drug Research University of Helsinki Helsinki 00014 Finland
3. Center for Biophotonics University of California Davis Sacramento CA 95817 USA
4. College of Chemistry Central China Normal University Wuhan 430079 China
5. Department of Pharmaceutical Sciences University of Padova Padua 35131 Italy
6. University of California Davis Comprehensive Cancer Center Sacramento CA 95817 USA