1. Department of Chemistry and Biochemistry, University of California, Santa Cruz, Santa Cruz, California 95064, United States
2. Pasarow Mass Spectrometry Laboratory, Jane and Terry Semel Institute for Neuroscience and Human Behavior and Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine at UCLA, Los Angeles, California 90024, United States
3. Department of Obstetrics and Gynecology, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, California 90095, United States