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61.
The objective of this study was to determine whether energy costs differed between 0 degrees , 3 degrees , and 6 degrees of camber during steady state overground wheeling. Three subject groups were examined: experienced wheelchair users with disabilities (thoracic lesion level 6 and below), nondisabled individuals with manual wheeling experience, and nondisabled individuals with no manual wheeling experience. Heart rate, rating of perceived exertion, visual analog scale for comfort, and a user preference questionnaire were collected for all subjects. Expired gas analysis data were collected for the group with disabilities. No statistically significant differences emerged in respiratory measures for camber angle or group. A camber of 6 degrees was most preferred in terms of stability on a side slope, hand comfort on the pushrims, maneuverability, and overall preference. Rear-wheel camber angle did not affect the energy expenditure of manual wheelchair propulsion, as measured by cardiopulmonary means. The individual manual wheelchair user's perceived level of comfort should be the determining factor in rear-wheel camber selection.  相似文献   
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Treatment of elderly patients with neoplasia is challenging. Age is a known prognostic factor in ovarian cancer but the optimal treatment of elderly patients has not been determined. We undertook a retrospective analysis to determine clinical practice in advanced-stage ovarian cancer patients older than 70 years of age. Methods: Medical records of women with high-grade serous ovarian cancer, stage III and IV were retrospectively analyzed. Results: A total of 735 patients were identified with a median age of 61.5 years. 22.4% among them were older than 70 years of age at diagnosis. First-line Progression-Free Survival (PFS) and Overall Survival (OS) were significantly worse in elderly patients in comparison to the younger ones [mPFS 11.3 months vs. 14.8 months, (p < 0.001) and mOS 30.2 months vs. 45.6 months (p < 0.001)]. However, elderly patients were characterized by worse ECOG-Performance Status and they were more frequently treated with Neoadjuvant Chemotherapy followed by Interval Debulking Surgery, while often they were more frequently denied debulking surgery compared to patients under 70 years of age. Moreover, elderly patients received more frequently monotherapy with platinum as frontline treatment. In contrast, there was no significant difference in the outcome of the debulking surgery in comparison to the younger patients or the frequency that gBRCA test was performed. Age over 70 years did not retain its significance for either Progression-Free Survival or Overall Survival when adjusted for all other reported prognostic factors. Conclusions: Elderly ovarian cancer patients have a worse prognosis. Comprehensive geriatric assessment should be performed for the optimal treatment of these patients.  相似文献   
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The aim of this study was to assess the effect of living away from, or in, the family home on the dietary habits of a group of Greek undergraduate University students. Eighty-four undergraduates at Athens Agricultural University, aged 20-24, completed a single, self-administered food habits questionnaire that asked about their current food practices and their food practices before they started University. Students living at home did not show major changes in their eating habits since starting University. Although students living away from the family home had made some positive changes, they decreased their weekly consumption of fresh fruit, cooked and raw vegetables, oily fish, seafood, pulses and olive oil, and increased their sugar, wine, alcohol and fast food intake. Between group comparisons of dietary changes showed that since starting University, students living away from home had developed more unfavourable eating habits than students living at the family home. These findings suggest that moving away from the family home and assuming responsibility for food preparation and purchasing for the first time affect dietary habits in this sample of Greek University students. Nutrition interventions in this young population should be encouraged to promote healthier diets and lifestyles, as well as adherence to the traditional Mediterranean diet.  相似文献   
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Background

Receptor protein tyrosine phosphatase beta/zeta (RPTPβ/ζ) is a chondroitin sulphate (CS) transmembrane protein tyrosine phosphatase and is a receptor for pleiotrophin (PTN). RPTPβ/ζ interacts with ανβ3 on the cell surface and upon binding of PTN leads to c-Src dephosphorylation at Tyr530, β3 Tyr773 phosphorylation, cell surface nucleolin (NCL) localization and stimulation of cell migration. c-Src-mediated β3 Tyr773 phosphorylation is also observed after vascular endothelial growth factor 165 (VEGF165) stimulation of endothelial cells and is essential for VEGF receptor type 2 (VEGFR2) - ανβ3 integrin association and subsequent signaling. In the present work, we studied whether RPTPβ/ζ mediates angiogenic actions of VEGF.

Methods

Human umbilical vein endothelial, human glioma U87MG and stably transfected Chinese hamster ovary cells expressing different β3 subunits were used. Protein-protein interactions were studied by a combination of immunoprecipitation/Western blot, immunofluorescence and proximity ligation assays, properly quantified as needed. RPTPβ/ζ expression was down-regulated using small interference RNA technology. Migration assays were performed in 24-well microchemotaxis chambers, using uncoated polycarbonate membranes with 8 μm pores.

Results

RPTPβ/ζ mediates VEGF165-induced c-Src-dependent β3 Tyr773 phosphorylation, which is required for VEGFR2-ανβ3 interaction and the downstream activation of phosphatidylinositol 3-kinase (PI3K) and cell surface NCL localization. RPTPβ/ζ directly interacts with VEGF165, and this interaction is not affected by bevacizumab, while it is interrupted by both CS-E and PTN. Down-regulation of RPTPβ/ζ by siRNA or administration of exogenous CS-E abolishes VEGF165-induced endothelial cell migration, while PTN inhibits the migratory effect of VEGF165 to the levels of its own effect.

Conclusions

These data identify RPTPβ/ζ as a cell membrane binding partner for VEGF that regulates angiogenic functions of endothelial cells and suggest that it warrants further validation as a potential target for development of additive or alternative anti-VEGF therapies.

Electronic supplementary material

The online version of this article (doi:10.1186/s12943-015-0287-3) contains supplementary material, which is available to authorized users.  相似文献   
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BACKGROUND:: Arsenic exposure has been linked to epigenetic modifications such as DNA methylation in in-vitro and animal studies. This association has also been explored in highly exposed human populations, but studies among populations environmentally exposed to low arsenic levels are lacking. METHODS:: We evaluated the association between exposure to arsenic, measured in toenails, and blood DNA methylation in Alu and Long Interspersed Nucleotide Element-1 (LINE-1) repetitive elements in elderly men environmentally exposed to low levels of arsenic. We also explored potential effect modification by plasma folate, cobalamin (vitamin B12), and pyridoxine (vitamin B6). The study population was 581 participants from the Normative Aging Study in Boston, of whom 434, 140, and 7 had 1, 2, and 3 visits, respectively, between 1999-2002 and 2006-2007. We used mixed-effects models and included interaction terms to assess potential effect modification by nutritional factors. RESULTS:: There was a trend of increasing Alu and decreasing LINE-1 DNA methylation as arsenic exposure increased. In subjects with plasma folate below the median (<14.1 ng/mL), arsenic was positively associated with Alu DNA methylation (β = 0.08 [95% confidence interval = 0.03 to 0.13] for one interquartile range [0.06 μg/g] increase in arsenic), whereas a negative association was observed in subjects with plasma folate above the median (β = -0.08 [-0.17 to 0.01]). CONCLUSIONS:: We found an association between arsenic exposure and DNA methylation in Alu repetitive elements that varied by folate level. This suggests a potential role for nutritional factors in arsenic toxicity.  相似文献   
67.
Using the Theory of Planned Behaviour (TPB), this study investigates weight control in overweight and obese participants (27 kg/m2 ? BMI < 45 kg/m2) taking part in a dietary intervention trial targeted at weight loss maintenance (n = 932). Respondents completed TPB measures investigating “weight gain prevention” at three time points. Correlation and regression analyses were used to investigate the relationship between TPB variables and weight regain. The TPB explained up to 27% variance in expectation, 14% in intention and 20% in desire scores. No relationship was established between intention, expectation or desire and behaviour at Time 1 or Time 2. Perceived need and subjective norm were found to be significantly related to weight regain, however, the model explained a maximum of 11% of the variation in weight regain. Better understanding of overweight individuals’ trajectories of weight control is needed to help inform studies investigating people’s weight regain behaviours. Future research using the TPB model to explain weight control should consider the likely behaviours being sought by individuals.  相似文献   
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ObjectivesTo assess secular changes in physical fitness (PF), moderate-to-vigorous-physical activity (MVPA) and TV-viewing in 1st-grade children from Crete, Greece.DesignCross-sectional cohorts examined in academic years 1992/93 and 2006/07.MethodsTwo representative samples of children, aged 5.9–7.8 years, were studied during 1992/93 (N = 606) and 2006/07 (N = 361). PF (sit-and-reach, standing-broad-jump, sit-ups and 20 m-shuttle-run-test) was assessed by the European-PF test battery and MVPA by a physical activity (PA) questionnaire. Data on the frequency of TV-viewing was also collected.ResultsBetween 1992/93 and 2006/07, there was a significant increase in all fitness tests in both genders (P < 0.001) and in MVPA in boys (76.5 min/week vs. 38.7 min/week, P < 0.001). Time spent watching TV on weekdays was significantly more in both genders in 2006/07, compared to 1992/93 (P < 0.001). In 2006/07, active boys and active girls spent more time in MVPA than active boys and girls in 1992/93 (P < 0.001). Significantly higher proportions of boys and girls engaged in vigorous activities in 2006/07, than 1992/93 (P < 0.001 and P = 0.027, respectively).ConclusionsA significant increase in physical and cardiorespiratory fitness in both genders and MVPA in boys was observed in children from Crete between 1992/93 and 2006/07. The increase in weekday TV-viewing, despite being parallel to an increase in leisure-time MVPA, could have an unfavorable effect on health and should be tackled in future interventions in this population. Dietary, anthropometric and biochemical indices should also be investigated to assess their impact on the secular changes in physical fitness and activity observed in this sample of children.  相似文献   
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