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1.
目的 基于《国际功能、残疾和健康分类》(ICF)构建智力和发展性残疾儿童青少年身体活动效益系统综述的范畴和PICO架构,探讨智力和发展性残疾儿童和青少年参加身体活动的健康效益。  相似文献   
2.
ObjectiveTo investigate the potential anti-tumor mechanisms of naphthoquinone compound shikonin (SKN) extracted from the root of Chinese herbal medicine plant lithospermum (Lithospermum erythrorhizon Sieb. & Zucc.).MethodsWe first observed that SKN treatment led to swelling and bubbles in HeLa cells that were similar to the phenotype of cell pyroptosis. Subsequently, the HeLa cells experienced a pyroptotic process with SKN, and this was then assessed using lactate dehydrogenase (LDH) release and propidium iodide (PI)/Hoechst double staining experiments. Pyroptosis is defined as gasdermin-mediated programmed necroptosis. To identify the potential pyroptosis machinery, two strategies were utilized that included a genome-wide clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 screening experiment and a pyroptosis reconstitution assay executed by each of the five known gasdermins (GSDMA-E). Moreover, endogenous cleavage was also detected in a panel of tumor cell lines.ResultsCompared with the control, both the LDH release and PI/Hoechst double-staining experiments suggested that SKN induced perforation and enhancement of the permeability of the cell membranes that resulted in pyroptosis in HeLa cells (P = .028 and P = .032, respectively). In addition, the reconstitution assays in human embryonic kidney 293T (HEK-293T) cells and endogenous cleavage assays in HeLa cells indicated that the pyroptosis was controlled by GSDME. In addition, we also found SKN could trigger pyroptosis in a panel of tumor cell lines in which the cellular morphologies were proportional to the GSDME expression levels. Additionally, the cleavage of GSDME was also detected, and this was indicative of a similar GSDME-mediated mechanism.ConclusionOur study not only explained the molecular mechanism of cytotoxicity of SKN to various tumor cells, but also provided additional information for the potential clinical application of natural naphthoquinone compounds against cancer.  相似文献   
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4.
《Dental materials》2022,38(6):1044-1059
ObjectiveAssess the biological and physicochemical properties of AH Plus, BioRoot RCS and Pulp Canal Sealer (PCS) leachates with and without chlorhexidine (CHX).MethodsThe sealers were studied in no contact and 1-minute contact with CHX. For biological properties (antibacterial activity and cytotoxicity), leachates were formed in saline of freshly mixed, 1-, 7- and 28 days set sealers. The antibacterial properties of sealer leachates were investigated for planktonic and biofilm growth of E. faecalis, S. mutans, S.epidermidis and S.aureus. The 3-(4,5 dimethylthiazolyl-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was used to evaluate murine fibroblast cell viability after exposure to the leachates. The physical properties (water uptake, sorption, solubility, porosity, surface characteristics) of sealers and the pH of the immersion liquid (saline or distilled water) were also assessed over a 28-days period.ResultsCHX improved the antibacterial properties of the sealer leachates and reduced cell viability for all sealer leachates, except for freshly mixed PCS. BioRoot RCS leachates presented the highest antibacterial properties and cell viability with and without CHX contact. PCS was the material most affected by CHX in terms of physical properties, whereas for AH Plus, solubility was increased. CHX did not affect the physical properties of BioRoot RCS, except for solubility that was decreased. CHX contact did not change sealers’ alkalinity in distilled water whereas it increased it for AH Plus and BioRoot RCS in saline.SignificanceCHX improved the antibacterial efficacy of sealer leachates and either compromised or did not affect cell viability. CHX affected to various extent sealers’ physicochemical properties.  相似文献   
5.
BackgroundThe social ecological approach suggests that the spatial context among other factors influence physical activity behavior. Ample research documents physical environmental effects on physical activity. Yet, to date inconsistent associations remain, which might be explained by conceptual and methodological challenges in measuring the spatial dimensions of health behavior. We review methods applied to measure the spatial contexts in the social ecological physical activity literature.MethodsOnline databases and selected reviews were used to identify papers published between 1990 and 2020. A total of 2167 records were retrieved, from which 412 studies that used physical activity as a primary outcome variable, included measures of the physical environment and applied the main principles of the social ecological approach, were included.ResultsSubjective approaches were the dominant method to capture the spatial context of physical activities. These approaches were applied in 67% (n=279) of the studies. From the objective approaches an administrative unit was most prevalent and was applied in 29% (n=118) of the studies. The most comprehensive objective spatial methods that capture the true environmental exposure, were used only in 2% (n=10) of the studies.ConclusionsCurrent social ecological physical activity research applies simple conceptualizations and methods of the spatial context. While conceptual and methodological concerns have been repeatedly expressed, no substantive progress has been made in the use of spatial approaches. To further our understanding on place effects on health, future studies should carefully consider the choice of spatial approaches, and their effect on study results.  相似文献   
6.
Background and aimThe effects of physical activity and exercise on gaming disorder severity in individuals with gaming disorder are unknown. The present study aimed to address the empirical gap in the current literature by comparing the effects of virtual reality-based training (VRT) and aerobic training (AT) exercise programs on gaming disorder severity, physical activity, physical fitness, and anxiety versus control group.Materials and methodsForty-four young male adults (18–28 years) with gaming disorder and a sedentary lifestyle were included in the study. The primary outcomes of the study were changes in gaming disorder severity and physical activity, and secondary outcomes included changes in physical fitness and anxiety levels. The participants were randomly assigned to VRT (n = 15), AT (n = 14) and control (n = 15) groups. Training sessions were performed at 50–70% of the maximal heart rate. Exercise programs consisted of 6 weeks of training 3 times a week for 30 min.ResultsThere was a decrease in the severity of gaming disorder as well as an increase in the level of physical activity in the VRT and AT exercise groups compared to the control group. In addition, a reduction was observed in the gaming time and sedentary time in both exercise groups versus control group. VRT group experienced greater improvements in physical fitness parameters than the AT group.ConclusionVRT and AT were effective in reducing gaming time and the severity of gaming disorder in individuals with gaming disorder. The therapeutic effects of VRT and AT can be used for reducing the severity of gaming disorder.  相似文献   
7.
The development and implementation of school policies is considered a key strategy for the promotion of physical activity (PA) in children and adolescents. This study aimed to systematically review and synthesise existing literature focusing on the associations between formal written school-based PA policies and (a) school PA practices and (b) PA behaviours of school-aged children and adolescents. Fifty-one papers reporting on 52 studies met the eligibility criteria. All but two studies were from high income countries, most used cross-sectional designs and demonstrated fair methodological quality, and just over a third examined language aspects of policies. Findings predominantly indicated a lack of or inconclusive associations between the various characteristics examined and PA outcomes. Inconclusive associations were identified between both PA practice and behaviour outcomes and state level policies, policies focusing on PE and school-day PA, and in studies examining language aspects of policies. Inconclusive associations with both types of outcomes were more likely to be identified compared to a lack of associations in studies using self-report measures and in studies not providing information about the quality of exposure and outcome measures used. Overall, findings highlight the need for further research that acknowledges the complex relationship between school policies and PA outcomes and employs robust methodological approaches to enhance our understanding of this area.  相似文献   
8.
PurposeTo examine the longitudinal associations of subjectively-measured physical activity (PA) and screen time with multiple domains of cognitive development in a sample of young children.MethodsParticipants were 96 children (baseline age: 3.69 ± 0.78 years) and their parents from Edmonton, Canada in the Physical Activity and Cognition in Early Childhood (PACE) study. Different types of PA (organized, non-organized) and screen time (television viewing, video games) were measured using a parental questionnaire at baseline and at 6- and 12-month follow-ups. Total proxy-reported PA, total screen time, and meeting/not meeting the screen time recommendations (2–4 years: ≤1 h/d; 5 years: ≤2 h/d) of the Canadian 24-Hour Movement Guidelines were also calculated. Working memory (Nebraska Barnyard task) and inhibitory control (Fish-Shark Go/No-Go task) were assessed at the three time points. Intellectual ability, including language development, inductive reasoning, and perceptual speed, were assessed using the Woodcock-Johnson III test battery at 6- and 12-month follow-ups. Multilevel growth modeling was conducted.ResultsOrganized PA (B = 1.26; 95%CI: 0.19,2.33), non-organized PA (B = 0.89, 95%CI: 0.08, 1.71), and total proxy-reported PA (B = 1.03, 95%CI: 0.41,1.66) were positively associated with intellectual ability. In particular, positive associations in regard to language development and inductive reasoning were observed. As for screen time, most associations were not significant, except for positive associations of meeting the screen recommendation with intellectual ability (B = 3.19; 95%CI: 0.002,6.38) and language development (B = 4.32; 95%CI: 0.34,8.30).ConclusionFor young children, promoting PA participation in organized and non-organized activities, as well as meeting the screen time recommendations, appears important for cognitive development.  相似文献   
9.
BackgroundAfter anterior cruciate ligament reconstruction (ACLR), the decision to allow a return to running is empirical, and the post-operative delay is the most-used criterion. The Quadriceps isokinetic-strength Limb Symmetry Index (Quadriceps LSI), with a cutoff of 60%, could be a useful criterion.ObjectiveTo determine the association between a Quadriceps LSI  60% and return to running after ACLR.MethodsOver a 10-year period, we retrospectively included 470 patients who underwent ACLR. Four months after ACLR, participants performed an isokinetic test; quadriceps concentric peak torque was used to calculate the Quadriceps LSI at 60?/s. With a Quadriceps LSI  60%, a return to running was suggested. At 6 months after ACLR, participants were clinically evaluated for a return to sport and post-operative middle-term complications. A multivariable predictive model was built to assess the efficiency diagnosis of this cutoff in order to consider cofounding factors. Quadriceps LSI cutoff  60% was assessed with sensitivity, specificity and the area under the receiver operating characteristic curve (AUC).ResultsAccording to our decision-making process with the 60% Quadriceps LSI cutoff at 60?/s, 285 patients were authorized to return to running at 4 months after ACLR and 185 were not, but 21% (n = 59) and 24% (n = 45), respectively, were not compliant with the recommendation. No iterative autograft rupture or meniscus pathology occurred at 6 months of follow-up. On multivariable logistic regression analysis, a return to running by using the 60% Quadriceps LSI cutoff was associated with undergoing the hamstring strand procedure (odds ratio 2.60, 95% confidence interval [CI] 1.75–3.84; P < 0.0001) and the absence of knee complications (1.18, 1.07–1.29; P = 0.001) at 4 months. The sensitivity and specificity of the 60% Quadriceps LSI cutoff were 83% and 70%, respectively. The AUC was 0.840 (95% CI 0.803–0.877).ConclusionsUsing the 60% cutoff of the isokinetic Quadriceps LSI at 4 months after ACLR could help in the decision to allow a return to running.  相似文献   
10.
BackgroundBreast cancer survivors (BCS), particularly Latina BCS, experience weight gain and reduced physical activity (PA) post-treatment increasing the risk for recurrence. There is a lack of evidence on the intensity and type of PA needed to engage cultural subgroups and improve clinical outcomes. This study developed and piloted two non-traditional PA interventions among a diverse sample of BCS.MethodsTwenty BCS (65% Latina; age 25–75) participated in a 2-arm parallel group-randomized pilot study to test the effects of an 8-week Latin dance and Qigong/Tai Chi intervention on PA and body composition. A seven-day pedometer protocol was used to measure steps/week and a bioelectric impedence scale was used to assess BMI and %body fat. T-tests were used to examine preliminary outcomes across both interventions and within intervention arms.ResultsThere were no significant changes in steps/week, BMI, or %body fat across or in each separate intervention. A small effect size for increase in steps/day was found among participants in the Qigong/Tai Chi arm (0.10) and low-to-moderate effect sizes for reductions in % body fat overall (0.36), and separately for participants in Latin dance (0.26) and Qigong/Tai Chi (0.46).ConclusionLatin dance and Qigong/Tai Chi are engaging and acceptable PA modalities that are promising for improving PA and body fat among diverse, high-risk BCS. Our findings highlight the need to continue to reach and engage high-risk BCS, including Latina survivors, using novel, culturally-sensitive PA interventions. Future studies should extend and more rigorously test these novel approaches to improving outcomes associated with recurrence.  相似文献   
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