1. The Pasarow Mass Spectrometry Laboratory, NPI-Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, California, USA
2. Thermo Fisher Corporation, San Jose, California, USA
3. School of Dentistry, University of California-Los Angeles, Los Angeles, California, USA
4. Department of Chemistry and Biochemistry and Department of Biological Chemistry, University of California-Los Angeles, Los Angeles, California, USA