1. Department of Molecular and Medical Pharmacology, Crump Institute for Molecular Imaging, David Geffen School of Medicine, University of Los Angeles at Los Angeles, Los Angeles, California, USA
2. School of Dentistry, University of Los Angeles at Los Angeles, Los Angeles, California, USA
3. Department of Periodontics, School of Dentistry, University of Washington, Seattle, Washington, USA
4. Microbial and Environmental Genomics, J. Craig Venter Institute, La Jolla, California, USA
5. West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China