Effects of winter skiing on stress, heart rate, apprehension, and enjoyment in collegiate students: a single randomized controlled trial.

This study investigated the effect of winter skiing on stress levels in collegiate students and also observed psychological factors related to heart rate, apprehension, and enjoyment. Two hundred thirty-eight male students were randomly classified into the control group (n=117) or the ski group (n=121). The control group received lectures on skiing; however, the ski group received practical ski training. Psychological measures included stress, apprehension, and enjoyment; physical measures included heart rate at pre- and postday. There were significant correlations between stress and apprehension (r=0.366) and stress and enjoyment (r=-0.441). Specifically, apprehension negatively correlated with enjoyment (r=-0.599). Between both groups, a significant interaction effect was found among stress, apprehension, and enjoyment. Moreover, compared with the control group, the ski group's stress and apprehension were significantly reduced, whereas the enjoyment was significantly enhanced. This study suggests that winter skiing is a suitable sport for reducing stress and providing a high level of enjoyment for collegiate students.

Cytoplasmic phospholipase A2 metabolites play a critical role in pulmonary tumor metastasis in mice.

BACKGROUND: Cytoplasmic PLA(2) (cPLA2) has been shown to be the major enzyme responsible for arachidonic acid (AA) release. Because of this key role of cPLA(2) in AA production, cPLA(2) involvement in tumorigenesis has been suggested. However, contradictory data are found in the literature. Additionally, little is known regarding the role of cPLA(2) in pulmonary tumor metastasis. MATERIALS AND METHODS: Tumor metastases were detected by lung colonization and angiogenesis was assayed as growth of blood vessels from subcutaneous tissue into an implanted matrigel of basement membrane. The matrix metalloproteinases (MMP)-2, and MMP-9 were detected by PCR with sequence-specific primers. RESULTS: In this study, the effects of inhibitors of cPLA2, 5-lipoxygenase (5-LO), and cyclooxygenase (COX)-2 on pulmonary metastasis formation by B16F10 melanoma cells were investigated. All of these inhibitors reduced B16F10 pulmonary metastasis formation in a dose-dependent manner. Importantly, cPLA2, and 5-LO, and COX-2 inhibitors reduced platelet-activating factor-induced angiogenesis in an in vivo mouse model employing Matrigel injected subcutaneously, and also reduced expression of MMP-2 and MMP-9 in the lungs. CONCLUSION: This study demonstrates that cPLA(2) metabolites play critical roles in tumor metastasis via the promotion, at least in part, of angiogenesis and MMP expression.

CpG-ODN-based immunotherapy is effective in controlling the growth of metastasized tumor cells.

Synthetic oligodeoxynucleotides (ODN) containing unmethylated CpG motifs (CpG-ODN) act as potent immune stimulators by activating innate immunity through toll-like receptor 9. These immunomodulatory effects of CpG-ODN have been reported to be associated with anti-tumor immunity. In this study, we used a murine B16F10 melanoma model and a CT26 colon cancer model to assess whether CpG-ODN-based immunotherapy was effective in inhibiting tumor cells that have already metastasized to distant organs. Systemic administration of CpG-ODN after melanoma cell injection resulted in a significant inhibition of pulmonary colonization. When CpG-ODN was administered after tumor cell injection, it also inhibited pulmonary metastasis of the tumor cells, albeit to a lesser degree in the latter case. Systemic administration of CpG-ODN after subcutaneous inoculation of CT26 colon cancer cells diminished pulmonary metastasis from the primary tumor sites. Additionally, CpG-ODN also inhibited the growth of pulmonary colonization of the colon tumor cells when CpG-ODN was administered after the primary tumors had been surgically removed. These data indicate that CpG-ODN was effective in inhibiting pulmonary metastasis of the B16F10 melanoma and CT26 colon cancer cells, as well as the growth of metastasized tumor cells. Our results suggest that CpG-ODN-based immunotherapy may be beneficial in controlling micrometastasis after surgery in clinical settings.