Endemic areas of human T-lymphotropic virus type 1 (HTLV-1) have been reported in Japan as well as tropical Africa, Central and South America and Melanesia. The existence of two subgroups, i.e., the transcontinental and Japanese subgroups, was reported in Japan. In the present study, we provide data on the ratio of the two subgroups in each endemic area and infection foci and examine the distribution of HTLV-1 in Japan and neighboring areas. A 657 bp fragment of env region of HTLV-1 proviral genome was successfully amplified for 183 HTLV-1 positive DNA samples. The subgroup determination was done by RFLP reactions using endonucleases HpaI and HinfI. The northern part of mainland Kyushu, represented by Hirado and Kumamoto, was monopolized by the Japanese subgroup, while the transcontinental subgroup ranged from 20 to 35% in the Pacific coast areas of Shikoku (Kochi), the Ryukyu Archipelago (Kakeroma and Okinawa) and Taiwan. An interesting finding in the present study is the presence of the transcontinental subgroup in Kochi, suggesting the endemicity of the transcontinental subgroup along the Kuroshio Current.

Objective To establish an SD rats animal model for preventive nursing of pressure ulcer.Methods 30 healthy male SD rats were randomly and averagely divided into 6 groups, which were put in simple compression devices supinely after anesthesia, with their hind limb joints regarded as oppressed points.The pressure of each group was: 70, 64, 58, 53, 48 and 44mmHg, respectively. By observing skin color change after two hours of compression and then calculating LD50, the pressure that made half animals' compression skin red was obtained. Results No group had visible skin damages and other serious changes, but compression local skin redness was found. Under the experimental conditions, the pressure of the skin redness among half of the animals was 55.08 mmHg. Conclusions In this model, the most appropriate pressure was 55.08 mmHg. The SD rats pressure ulcer animal model is feasible and could be applied to animal studies on preventive nursing of pressure ulcer.