Funding for this research was provided by:
a Korea University Grant
a grant from Korea University Anam Hospital
the Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education (NRF-2015R1D1A1A02061859)
the Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Science, ICT, & Future Planning (NRF-2012R1A1A1013260)
Received: 9 July 2019
Accepted: 18 September 2019
First Online: 1 October 2019
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board of Korea University Medical Center Anam Hospital and informed consent was waived.
: Not applicable.
: The authors declare that they have no competing interests.