Funding for this research was provided by:
the Japan Society for the Promotion of Science (17H03616, 17H06428)
Japan Agency for Medical Research and Development (18ek0109266h0002)
National Center for Child Health and Development (26-11)
the Takeda Foundation (not applicable)
Received: 6 December 2018
Accepted: 10 May 2019
First Online: 28 May 2019
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board Committee at the National Center for Child Health and Development and was performed after obtaining written informed consent from the participants or their parents.
: Consent for publication is obtained from the participants or their parents.
: The authors declare that they have no competing interests.
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