Association between Tai Chi Yuttari Exercise and Longevity and Prevention of Long-Term Care Need: Survival Analysis in Kitakata City, Japan.

This study examined whether participation in Tai Chi Yuttari exercise is associated with a delay in the death and new certification for long-term care need of older adults. Individuals who participated in Tai Chi Yuttari exercise classes in 2011-2015 (participation group) were compared with individuals from the Basic Resident Register of Kitakata City (non-participation group). Death and new certification for long-term care need were selected to evaluate the effectiveness of participation in Tai Chi Yuttari exercise classes. The periods from the start date of the observation to each person's date of occurrence of events were calculated. The Kaplan-Meier method and log-rank test were used to compare survival curves between the groups. A total of 105 and 202 individuals in the participation and non-participation groups, respectively, were observed. Survival duration (χ2 = 8.782, p = 0.003) and the period before receiving certification for long-term care (χ2 = 5.354, p = 0.021) were longer in the participation group than in the non-participation group. In the stratified analysis by sex, survival duration was longer in the participation group in men only (χ2 = 7.875, p = 0.005). Participation in Tai Chi Yuttari exercise might be effective in delaying death, especially in men, and new certification for long-term care.

Efficient vitrification of mouse embryos using the Kitasato Vitrification System as a novel vitrification device.

BACKGROUND: Currently, the cryopreservation of embryos and oocytes is essential for assisted reproductive technology (ART) laboratories worldwide. This study aimed to evaluate the efficacy of the Kitasato Vitrification System (KVS) as a vitrification device for the cryopreservation of mouse embryos to determine whether this novel device can be adapted to the field of ART. METHODS: In Experiment 1, blastocysts were vitrified using the KVS. Vitrified blastocysts were warmed and subsequently cultured for 72 h. In Experiment 2, 2-cell-stage embryos were vitrified using the KVS, and vitrified embryos were warmed and subsequently cultured for 96 h. In Experiment 3, we evaluated the in vivo developmental potential of vitrified 2-cell-stage embryos using the KVS, and in Experiment 4, we evaluated the cooling and warming rates for these devices using a numerical simulation. RESULTS: In Experiment 1, there were no significant differences between the survival rates of the KVS and a control device. However, re-expanded (100%) and hatching (91.8%) rates were significantly higher for blastocysts vitrified using the KVS. In Experiment 2, there were no significant differences between the survival rates, or rates of development to the blastocyst stage, of vitrified and fresh embryos. In Experiment 3, after embryo transfer, 41% of the embryos developed into live offspring. In Experiment 4, the cooling and warming rates of the KVS were 683,000 and 612,000 °C/min, respectively, exceeding those of the control device. CONCLUSIONS: Our study clearly demonstrates that the KVS is a novel vitrification device for the cryopreservation of mouse embryos at the blastocyst and 2-cell stage.