Funding for this research was provided by:
National Institutes of Health (K12DK083021)
Received: 26 July 2015
Revised: 29 August 2016
Accepted: 1 September 2016
First Online: 13 September 2016
Compliance with Ethical Standards
: No competing financial interests exist.
: Informed consent was obtained from all individual participants included in the study.
: All procedures were in accordance with the ethical standards of the institutional review board at the University of California, San Francisco.