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21.
Kevin W. Sexton Charles L. Rodriguez-Feo Richard B. Boyer Gabriel A. Del Corral David C. Riley Alonda C. Pollins Nancy L. Cardwell R. Bruce Shack Lillian B. Nanney Wesley P. Thayer 《Hand (New York, N.Y.)》2015,10(4):688-694
Background
Hydrophilic polymers have been shown to improve physiologic recovery following repair of transected nerves with microsutures. Our study was designed to combine hydrophilic polymer therapy with nerve tubes (NT) to enhance polymer delivery to the site of nerve injury.Methods
Using a rat sciatic nerve injury model, a single transection injury was repaired in an end-to-end fashion with NT + polyethylene glycol (PEG) to NT alone. Compound action potentials (CAPs) were recorded before nerve transection and after repair. Behavioral testing was performed for 5 weeks.Results
PEG therapy restored CAPS in all, but one, animals, while no CAPS were recorded in animals not receiving PEG. Behavioral nerve function was measured using the standardized functional assessment technique and foot fault asymmetry scores (FF). FF scores were improved for the PEG therapy groups on postoperative days 7, 14, and 21. However, after expected eventual axonal outgrowth, the benefit was less noticeable at days 28 and 35. Immunohistochemistry of the distal axon segments showed an increase number of sensory and motor axons in the NT + PEG group as compared to NT alone.Conclusion
These data suggest that PEG delivery via a conduit may provide a simple, effective way to fuse severed axons and regain early nerve function. For proximal nerve injuries in large animals, recovery of axonal continuity could dramatically improve outcomes, even if fusion only occurs in a small percentage of axons. 相似文献22.
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Zoë Fitzgerald Armin Mohamed Monica Ricci Zoë Thayer Laurie Miller 《Journal of clinical neuroscience》2013,20(11):1486-1491
Recently, a pattern referred to as accelerated long-term forgetting (ALF) has been described in patients with epilepsy. In ALF, acquisition and retention over standard delayed recall intervals (up to 30 minutes) tend to be intact, but there is an abnormally rapid rate of forgetting over delays of days or weeks. ALF is associated with everyday memory complaints as well as impairments in autobiographical memory, but goes largely undetected by traditional neuropsychological measures. We consider here the characteristics of ALF and possible contributors to its underlying pathophysiology. Overall, a better understanding of this relatively newly recognised memory disorder should improve clinical treatment. 相似文献
25.
Rebekka M. Lee Catherine M. Giles Angie L. Cradock Karen M. Emmons Cassandra Okechukwu Erica L. Kenney J. Thayer Steven L. Gortmaker 《Journal of the Academy of Nutrition and Dietetics》2018,118(8):1425-1437
Background
Afterschool interventions have been found to improve the nutritional quality of snacks served. However, there is limited evidence on how these interventions affect children’s snacking behaviors.Objective
Our aim was to determine the impact of an afterschool intervention focused at the school district, site, family, and child levels on dietary consumption of foods and beverages served at snack.Design
This was a secondary analysis of a group-randomized controlled trial.Participants/setting
Data were collected from 400 children at 20 afterschool sites in Boston, MA before (fall 2010) and after (spring 2011) intervention implementation.Intervention
The Out-of-School Nutrition and Physical Activity intervention aimed to promote fruits, vegetables, whole grains, and water, while limiting sugary drinks and trans fats. Researchers worked with district foodservice staff to change snack foods and beverages. Teams of afterschool staff participated in three 3-hour learning collaborative sessions to build skills and created action plans for changing site practices. The intervention included family and child nutrition education.Main outcome measures
Research assistants observed dietary snack consumption using a validated measure on 2 days per site at baseline and follow-up.Statistical analyses performed
This study used multivariable regression models, accounting for clustering of observations, to assess the intervention effect, and conducted post-hoc stratified analyses by foodservice type.Results
Children in intervention sites had greater decreases in consumption of juice (–0.61 oz/snack, 95% CI –1.11 to –0.12), beverage calories (–29.1 kcal/snack, 95% CI –40.2 to 18.0), foods with trans fats (–0.12 servings/snack, 95% CI –0.19 to –0.04), total calories (–47.7 kcal/snack, 95% CI –68.2 to –27.2), and increases in consumption of whole grains (0.10 servings/snack, 95% CI 0.02 to 0.18) compared to controls. In post-hoc analyses, sites with on-site foodservice had significant improvements for all outcomes (P<0.001), with no effect for sites with satellite foodservice.Conclusions
Results demonstrate that an afterschool intervention can improve children’s dietary snack consumption, particularly at sites with on-site foodservice. 相似文献26.
Anita L. Hansen Gina Olson Lisbeth Dahl David Thornton Bj?rn Grung Ingvild E. Graff Livar Fr?yland Julian F. Thayer 《Nutrients》2014,6(12):5405-5418
The aim of the present study was to investigate the effects of Atlantic salmon consumption on underlying biological mechanisms associated with anxiety such as heart rate variability (HRV) and heart rate (HR) as well as a measure of self-reported anxiety. Moreover, these biological and self-reported outcome measures were investigated in relation to specific nutrients; vitamin D status, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Ninety-five male forensic inpatients were randomly assigned into a Fish (Atlantic salmon three times per week from September to February) or a Control group (alternative meal, e.g., chicken, pork, or beef three times per week during the same period). HRV measured as the root mean square of successive differences (rMSSD), HR, state- and trait-anxiety (STAI), were assessed before (pre-test) and at the end of the 23 weeks dietary intervention period (post-test). The Fish group showed significant improvements in both rMSSD and HR. The Fish group also showed significant decreases in state-anxiety. Finally, there was a positive relationship between rMSSD and vitamin D status. The findings suggest that Atlantic salmon consumption may have an impact on mental health related variables such as underlying mechanisms playing a key role in emotion-regulation and state-anxiety. 相似文献
27.
Rapid prenatal diagnosis of beta thalassemia using DNA amplification and nonradioactive probes 总被引:3,自引:0,他引:3
We used in vitro DNA amplification by the polymerase chain reaction and nonradioactive probes for prenatal diagnosis of beta thalassemia in Chinese from the Guangdong province. Exact molecular diagnoses were made in all 20 fetuses studied over a 6-month period. We conclude that this method of prenatal diagnosis for beta thalassemia is a viable approach in many parts of the world where this disease is common. 相似文献
28.
Andrew A. Rooney Abee L. Boyles Mary S. Wolfe John R. Bucher Kristina A. Thayer 《Environmental health perspectives》2014,122(7):711-718
Background: Systematic-review methodologies provide objectivity and transparency to the process of collecting and synthesizing scientific evidence in reaching conclusions on specific research questions. There is increasing interest in applying these procedures to address environmental health questions.Objectives: The goal was to develop a systematic-review framework to address environmental health questions by extending approaches developed for clinical medicine to handle the breadth of data relevant to environmental health sciences (e.g., human, animal, and mechanistic studies).Methods: The Office of Health Assessment and Translation (OHAT) adapted guidance from authorities on systematic-review and sought advice during development of the OHAT Approach through consultation with technical experts in systematic review and human health assessments, as well as scientific advisory groups and the public. The method was refined by considering expert and public comments and through application to case studies.Results and Discussion: Here we present a seven-step framework for systematic review and evidence integration for reaching hazard identification conclusions: 1) problem formulation and protocol development, 2) search for and select studies for inclusion, 3) extract data from studies, 4) assess the quality or risk of bias of individual studies, 5) rate the confidence in the body of evidence, 6) translate the confidence ratings into levels of evidence, and 7) integrate the information from different evidence streams (human, animal, and “other relevant data” including mechanistic or in vitro studies) to develop hazard identification conclusions.Conclusion: The principles of systematic review can be successfully applied to environmental health questions to provide greater objectivity and transparency to the process of developing conclusions.Citation: Rooney AA, Boyles AL, Wolfe MS, Bucher JR, Thayer KA. 2014. Systematic review and evidence integration for literature-based environmental health science assessments. Environ Health Perspect 122:711–718; http://dx.doi.org/10.1289/ehp.1307972 相似文献
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