Fitness promotion in college: the relationships among students' perceived physical literacy, knowledge, and physical fitness.

Purpose: The purpose of this study was to examine the relationships among perceived physical literacy (PPL), knowledge of physical activity and fitness (PAF knowledge), and physical fitness. Methods: Undergraduates (N = 968, female = 414; Mage = 18.64) from a public university in central China completed a simplified Chinese version of the PPL instrument, an online test for PAF knowledge, and seven health-related physical fitness tests. The PPL includes three dimensions: (a) confidence and physical competence, (b) motivation, and (c) interaction with the environment. The fitness tests measured lung capacity, body mass index (BMI), and performances in 800 (female)/1000 (male) meters run, 50 meters dash (50 M), sit-up (female) / pull-up (male), standing long jump (SLJ), and sit-and-reach. Results: PPL and its dimensions significantly predicted six fitness test performances both in male (ß: -0.42 - 0.37; p < 0.01-0.05; R2: 0.01-0.13) and female (ß: -0.59 - 0.49; p < 0.01-0.05; R2: 0.03-0.13) students. PAF knowledge (ß: -0.17 - 0.18; p < 0.01-0.05; R2: 0.01-0.05) significantly predicted BMI (males) and performances in 50 M (females) and SLJ (females) tests. Conclusion: To support college students' fitness development and maintenance, tailored physical activity and fitness promotion programs are needed to strengthen students' PPL and PAF knowledge.

[Experimental study on influence of bone marrow mesenchymal stem cells on activation and function of mouse peritoneal macrophages].

OBJECTIVE: To explore the influence of bone marrow (BM) mesenchymal stem cells (MSCs) on macrophage activation after lipopolysaccharide (LPS) stimulation. METHODS: Mouse BM MSCs were isolated and purified by adherence screening, and mouse peritoneal macrophages (MPM) were collected by sodium thioglycollate peritoneal injection, and the co-culture system was established by planting macrophages on the MSCs monolayer. The grouping of experiments: group A: MPM; group B: MPM + LPS; group C: MPM + LPS + MSC; group D: MPM + LPS + MSC supernatant. Cell culture supernatants were collected to detect the changes of TNF-alpha/TGF-beta and nitrogen monoxide (NO) after stimulating macrophages with LPS for 18 hours. At the same time Escherichia coli standard strain (ATCC25922) was added into the culture system and incubated for another 24 hours, macrophages were stained and phagocytosis were examined. RESULTS: The concentrations of TNF-alpha and NO in culture supernatants were increased significantly to (147.4 +/- 37.1) pg/ml and (59.9 +/- 8.7) micromol/L respectively after macrophage activation, however, at the present of MSC, the concentration of TNF-alpha was dramatically decreased [(97.6 +/- 30.3) pg/ml, P = 0.032], and the concentration of NO was decreased to (50.9 +/- 29.5) micromol/L (P > 0.05). The concentrations of TNF-alpha and NO were further decreased after addition of MSC supernatants [(58.3 +/- 31.5) pg/ml and (-3.4 +/- 2.3) micromol/L respectively, P < 0.01]. There was no change in the phagocytic rate and phagoindex of macrophages after activation. CONCLUSIONS: MSCs can inhibit the activation of mouse peritoneal macrophages after stimulating with LPS but has no influence on the phagocytosis.

[Effects of mesenchymal stem cells on proliferation and apoptosis of allogeneic B lymphocytes].

OBJECTIVE: To study the influence of bone marrow mesenchymal stem cells (MSC) on the proliferation and apoptosis of allogeneic peripheral B lymphocytes in vitro. METHODS: MSCs were isolated from the peripheral blood of healthy volunteer and cultured. B lymphocytes were isolated from another healthy volunteer and co-cultured with the MSCs at the B:MSC ratios of 50:1, 10:1, and 1:1 or with different concentrations of MSC supernatant (12.5%, 25%, and 50%) for 72 h, in the presence of antihuman IgM immunoglobulin goat antibodies (Anti-IgM) at a final concentration of 10 microg/mlL. The proliferation of B lymphocytes was analyzed with MTT assay. B lymphocytes and MSC were co-cultured at the ratio of 1:1 for 24 h or 48 h, with or without addition of Anti-IgM. Flow cytometric was used to detect the apoptosis of B lymphocytes. RESULTS: The A value of B lymphocytes co-cultured with MSCs at different ratios were 0.521 +/- 0.093, 0.418 +/- 0.103, and 0.365 +/- 0.114 respectively. The A values of Group10:1 and Ggroup1:1 were both significantly lower than that of the control group (0.679 +/- 0.049, both P < 0.01), and the A value of Ggroup1:1 was significantly lower than that of Group10:1 (P < 0.05). The A value of B lymphocytes co-cultured with 50% MSC supernatant was 0.504 +/- 0.099, significantly lower than those of the control group and Group 12.5% (both P < 0.05). MSCs didn't induce apoptosis of B lymphocytes. The apoptosis rates of B lymphocytes co-cultured with MSCs for 24 h or 48 h, in presence or absence of Anti-IgM were 1.90% +/- 0.75%, 2.33% +/- 1.01%, 2.33% +/- 0.75%, and 1.39% +/- 0.63% respectively, without significant difference between any 2 of the four groups. CONCLUSION: MSC and its supernatant inhibit B lymphocyte proliferation with the mechanism correlated with the MSC concentration and the MSC-secreted cytokine, but MSCs does not induce B lymphocytes apoptosis in vitro.