Endurance training slows breast tumor growth in mice by suppressing Treg cells recruitment to tumors

BACKGROUND: Aerobic exercise has been shown to slow tumor progression in rodents and humans, but the mechanisms behind this effect are still unclear. Here we show that aerobic exercise in the form of chronic endurance training suppresses tumor recruitment of FoxP3+ Treg cells thus enhancing antitumor immune efficiency. METHODS: Adult wild-type and athymic BALB/c female mice were endurance-trained for 8 weeks. Circulating leukocytes as well as muscle and liver mtDNA copy number were compared to aged-matched concurrent sedentary controls to establish systemic effects. 4 T1 murine mammary tumor cells were injected subcutaneously to the 4th mammary pad at the end of the training period. Tumor growth and survival rates were compared, together with antitumor immune response. RESULTS: Exercised wild-type had 17% slower growth rate, 24% longer survival, and 2-fold tumor-CD+ 8/FoxP3+ ratio than sedentary controls. Exercised athymic BALB/c females showed no difference in tumor growth or survival rates when compared to sedentary controls. CONCLUSIONS: Cytotoxic T cells are a significant factor in endurance exercise-induced suppression of tumor growth. Endurance exercise enhances antitumor immune efficacy by increasing intratumoral CD8+/FoxP3+ ratio

GPS-based regional ionospheric models and their suitability in Antarctica

There are a number of ionospheric models available for research and application, such as the polynomial model, generalized trigonometric series function model, low degree spherical harmonic function model, adjusted spherical harmonic function model, and spherical cap harmonic function analysis. Using observations from more than 40 continuously operating stations across Antarctica in 2010, five models are compared with regard to their precision and applicability to polar regions. The results show that all the models perform well in Antarctica with 0.1 TECU of residual mean value and 2 TECU of root mean square error

Progress in Chinese Antarctic geodetic remote sensing

This paper summarizes the progress of the Chinese Antarctic expedition in geodetic remote sensing. It describes the systems for continuous satellite navigation and positioning, and the tide gauges that have been established at the Zhongshan and Great Wall stations in Antarctica. Advances in the investigation of plate motion, the gravity field, and sea level change as well as the application of GPS in atmospheric studies are reported. Details of the movements of ice sheets and glaciers, distributions of blue ice and ice crevasses, and mass balance studies based on remote sensing techniques are presented. The use of field, satellite, and photogrammetric data to produce topographic maps is described. Finally, the prospects for further Antarctic surveying and mapping are discussed. In the near future, we will establish a high-precision geodetic datum in the Chinese Antarctic expedition areas, monitor changes of Antarctic snow and ice, and develop a platform for sharing Antarctic resource and environment information