Are there risk factors in alpine skiing? A controlled multicentre survey of 1278 skiers

OBJECTIVE: To analyse risk factors in alpine skiing. DESIGN: A controlled multicentre survey of injured and non-injured alpine skiers. SETTING: One tertiary and two secondary trauma centres in Bern, Switzerland. PATIENTS AND METHODS: All injured skiers admitted from November 2007 to April 2008 were analysed using a completed questionnaire incorporating 15 parameters. The same questionnaire was distributed to non-injured controls. Multiple logistic regression was performed. Patterns of combined risk factors were calculated by inference trees. A total of 782 patients and 496 controls were interviewed. RESULTS: Parameters that were significant for the patients were: high readiness for risk (p = 0.0365, OR 1.84, 95% CI 1.04 to 3.27); low readiness for speed (p = 0.0008, OR 0.29, 95% CI 0.14 to 0.60); no aggressive behaviour on slopes (p<0.0001, OR 0.19, 95% CI 0.09 to 0.37); new skiing equipment (p = 0.0228, OR 59, 95% CI 0.37 to 0.93); warm-up performed (p = 0.0015, OR 1.79, 95% CI 1.25 to 2.57); old snow compared with fresh snow (p = 0.0155, OR 0.31, 95% CI 0.12 to 0.80); old snow compared with artificial snow (p = 0.0037, OR 0.21, 95% CI 0.07 to 0.60); powder snow compared with slushy snow (p = 0.0035, OR 0.25, 95% CI 0.10 to 0.63); drug consumption (p = 0.0044, OR 5.92, 95% CI 1.74 to 20.11); and alcohol abstinence (p<0.0001, OR 0.14, 95% CI 0.05 to 0.34). Three groups at risk were detected: (1) warm-up 3-12 min, visual analogue scale (VAS)(speed) >4 and bad weather/visibility; (2) VAS(speed) 4-7, icy slopes and not wearing a helmet; (3) warm-up >12 min and new skiing equipment. CONCLUSIONS: Low speed, high readiness for risk, new skiing equipment, old and powder snow, and drug consumption are significant risk factors when skiing. Future work should aim to identify more precisely specific groups at risk and develop recommendations--for example, a snow weather index at valley stations.

CMC among multilingual students of English for academic purposes: linguistic and sociolinguistic communicative factors in online written responses

The present study examines linguistic and sociolinguistic factors in a Web-enhanced

Prevalence of tooth wear on buccal and lingual surfaces and possible risk factors in young European adults

To assess the prevalence of tooth wear on buccal/facial and lingual/palatal tooth surfaces and identify related risk factors in a sample of young European adults, aged 18-35 years. Calibrated and trained examiners measured tooth wear, using the basic erosive wear examination (BEWE) on in 3187 patients in seven European countries and assessed the impact of risk factors with a previously validated questionnaire. Each individual was characterized by the highest BEWE score recorded for any scoreable surface. Bivariate analyses examined the proportion of participants who scored 2 or 3 in relation to a range of demographic, dietary and oral care variables. The highest tooth wear BEWE score was 0 for 1368 patients (42.9%), 1 for 883 (27.7%), 2 for 831 (26.1%) and 3 for 105 (3.3%). There were large differences between different countries with the highest levels of tooth wear observed in the UK. Important risk factors for tooth wear included heartburn or acid reflux, repeated vomiting, residence in rural areas, electric tooth brushing and snoring. We found no evidence that waiting after breakfast before tooth brushing has any effect on the degree of tooth wear (p=0.088). Fresh fruit and juice intake was positively associated with tooth wear. In this adult sample 29% had signs of tooth wear making it a common presenting feature in European adults.

Personality factors in elementary school children: Contributions to academic performance over and above executive functions?

Unique contributions of Big Five personality factors to academic performance in young elementary school children were explored. Extraversion and Openness (labeled “Culture” in our study) uniquely contributed to academic performance, over and above the contribution of executive functions in first and second grade children (N = 446). Well established associations between Conscientiousness and academic performance, however, could only be replicated with regard to zero-order correlations. Executive functions (inhibition, updating, and shifting), for their part, proved to be powerful predictors of academic performance. Results were to some extent dependent on the criterion with which academic performance was measured: Both personality factors had stronger effects on grades than on standardized achievement tests, whereas the opposite was true for executive functions. Finally, analyses on gender differences revealed that Extraversion and Openness/Culture played a more dominant role in girls than in boys, but only regarding grades.

FUNCTIONS OF DEADENYLATION FACTORS IN MRNA DECAY AND MRNA PROCESSING BODY FORMATION

Most newly synthesized messenger RNAs possess a 5’ cap and a 3’ poly(A) tail. The process of poly(A) tail shortening, also termed deadenylation, is important for post-transcriptional gene regulation, because deadenylation not only leads to mRNA translational inhibition but also is the first step of major mRNA degradation. Translationally inhibited mRNAs can be stored and/or degraded in dynamic cytoplasmic foci termed mRNA processing bodies, or P bodies, which are conserved in eukaryotes. To shed new light on the mechanisms of P body formation and P body functions, I focused on the link between deadenylation factors and P bodies. I found that the two major deadenylation complexes, Pan3-Pan2 and Ccr4-Caf1, can both be enriched in P bodies. The deadenylase activity of the Ccr4-Caf1 complex is prerequisite for P body formation. Pan3, but not the deadenylase Pan2, is essential for P body formation. While the C-terminal domain of Pan3 is important for interaction with Pan2, Pan3 N-terminal domain is important for Pan3 to form cytoplasmic foci colocalizing with P bodies and to promote mRNA decay. Interestingly, Pan3 N-terminal domain may be phosphorylated to regulate Pan3 localization and functions. Aside from the functions of the two deadenylation complexes in P bodies, I also studied all reported human P body proteins as a whole using bioinformatics. This effort not only has generated a comprehensive picture of the functions of and interactions among human P body proteins, but also has predicted proteins that may regulate P body formation and/or functions. In summary, my study has established a direct link between mRNA deadenylation and P body formation and has also led to new hypotheses to guide future research on how P body dynamics are controlled.

Host factors in metastasis: Direct lysis of bloodborne metastatic tumor cells by murine vascular endothelial cells

During the process of cancer metastasis, the majority of circulating tumor cells arrest in microcapillary beds and then rapidly die. To study whether vascular endothelial cells can directly lyse tumor cells, we isolated vascular endothelial cells by perfusion of lungs from immunocompetent or nude mice. The cells were grown in culture, and then cloned and characterized. Cloned endothelial cells were incubated with several lymphokines and cytokines. Cells incubated with IFN-$\gamma$ and TNF lysed a variety of tumor cells with different metastatic potential. Mouse skin and lung fibroblasts treated with the same cytokines did not. Endothelial cell mediated tumor cell lysis was not due to different binding ability of tumor cells to cytokine treated and untreated endothelial monolayers. Kinetic studies demonstrated that the continuous presence of cytokines in the tumor-endothelial cocultures was necessary to produce maximal lysis of tumor cells. Target cell lysis was not due to the direct effects of IFN-$\gamma$ or TNF, since vascular endothelial cells isolated from the lung of nude mice lysed human melanoma cells that are sensitive or resistant to TNF. Cytokine treated endothelial cells produced a high level of nitric oxide, which is known to be cytotoxic to a variety of target cells. The level of nitric oxide production was directly correlated with the degree of tumor cell lysis. A specific inhibitor of nitric oxide synthesis(N$\sp{\rm G}$-monomethyl-L-arginine), completely inhibited production of nitric oxide and tumor cell lysis. Treatment of cytokine activated endothelial cells with dexamethasone also inhibited tumor cell lysis. This inhibition was independent of tumor-endothelial adhesion but correlated with inhibition of nitric oxide production. Collectively, these results suggest that vascular endothelial cells can directly destory tumor emboli and thus play an active role in the pathogenesis of cancer metastasis. ^