**Acknowledgements**

The authors would like to thank Achmad Adhipatria P. Kartamihardja, Khongorzul Erdene, Miski Aghnia Khairinisa, and Odgerel Zorigt for their researches. This article is based on many researchers' great works and our colleagues' experiments. We also thank Nobuko Kemmotsu for editing our manuscript with English correction. Our colleagues have graduated from Gunma University Graduate School of Medicine, and they came from Asian countries to Japan to join our program, "Asian Nuclear Medicine Graduate Program (ANMEG Program)." This program was supported by the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of the Japanese government. The mission of this program is to train specialists in nuclear medicine and radiology in medical fields who will become leading clinicians and researchers, both in their home countries and at an international level. The ANMEG program and MEXT supported them during their stay in Japan.
