1. Department of Pathology, Johns Hopkins University, Baltimore, Maryland.
2. Department of Oral and Maxillofacial Surgery, School of Stomatology, China Medical University, Shenyang, Liaoning Province, P.R. China.
3. UCLA and Orthopaedic Hospital Department of Orthopaedic Surgery and the Orthopaedic Hospital Research Center, Los Angeles, California.
4. Department of Surgery, Johns Hopkins University, Baltimore, Maryland.
5. School of Dentistry, University of California, Los Angeles, California.
6. Center For Cardiovascular Science and MRC Center for Regenerative Medicine, University of Edinburgh, Edinburgh, United Kingdom.