Received: 21 January 2021
Accepted: 3 May 2021
First Online: 14 May 2021
: We obtained written informed consent from all subjects, or from parents or legal guardians of those subjects aged below 18 years. This study was approved by the ethics committee of Kagoshima University (190245).All methods were performed in accordance with relevant guidelines and regulations.
: Not applicable.
: The authors declare no conflict of interest.