Mingming Liu1, Ikuo Igarashi2, Xuenan Xuan3. 1. School of Basic Medicine, Hubei University of Arts and Science, Xiangyang, China; National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Japan. 2. National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Japan. 3. National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Japan. Electronic address: gen@obihiro.ac.jp.