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991.

Objective

To assess the contribution of active travel to and from school to children's overall physical activity levels in England.

Method

Logistic regression models examining associations between active travel (walked, or cycled, to/from school at least once in the last week) and achievement of physical activity recommendations (≥ 60 min/d daily) in 4,468 children aged 5-15y (303 with valid accelerometry data) participating in the nationally-representative Health Survey for England 2008.

Results

The 64% of children who walked and the 3% who cycled to/from school were more active than the 33% who did neither. Typical walkers came from a deprived area and were less likely to have a limiting illness; typical cyclists were older, male, and most likely to meet the recommendations. For self-reported activity, time spent cycling to/from school contributed more to meeting the recommendations (OR1.31, 1.09-1.59) than time spent walking to/from school (OR1.08, 1.02-1.15) or in sports (OR1.17, 95% CI 1.14-1.20). Time spent walking to school (OR1.80, 1.41-2.30) and in sports (OR1.10, 1.01-1.20) were significantly associated with being in the highest tertile actigraph-measured activity.

Conclusion

Children who reported walking or cycling to school were more active. Longitudinal studies are required to ascertain whether encouraging active travel affects less active children.  相似文献   
992.

Purpose

Vitamin D is increasingly being recognized as an important mediator of immune function and may have a preventive role in the pathogenesis of periprosthetic joint infection. To the best of our knowledge, no other study has examined possible associations between periprosthetic joint infection and vitamin D deficiency. We investigated the rate of vitamin D deficiency in patients treated for periprosthetic joint infection and whether vitamin D deficiency is independent of other risk factors for vitamin D deficiency in patients with periprosthetic joint infection.

Methods

Serum 25-hydroxyvitamin D (25OHD) levels of every patient scheduled to receive a total prosthesis either of the hip, knee, or shoulder in the orthopaedic department of the Johannes-Guttenberg-University Hospital in Mainz, Germany (109 patients), were measured after admission. Furthermore, serum 25OHD levels were measured for every patient presenting with periprosthetic joint infection (n = 50) or aseptic loosening of the prosthesis (n = 31) scheduled to undergo revision surgery. The prevalence of normal (>30 ng/ml), insufficient (20–30 ng/ml), and deficient (<20 ng/ml) 25OHD levels was determined.

Results

All tested patient subgroups showed low vitamin D levels. Statistical analysis found no significant difference in vitamin D levels comparing patients with prosthesis and patients with aseptic prosthesis loosening (p = 0.58). Significant differences in 25OHD levels were found comparing patients with periprosthetic joint infection and patients scheduled for primary arthroplasty (p < 0.001). In addition, we found a significant difference (p < 0,001) in 25OHD levels of patients with periprosthetic joint infection compared with patients with aseptic prosthesis loosening.

Conclusion

We found a high frequency of vitamin D deficiency in patients being treated by primary arthroplasty and those with aseptic joint prosthetic loosening and periprosthetic joint infection. Vitamin D deficiency was severe in patients with periprosthetic joint infection.  相似文献   
993.
Here, we describe a newly generated transgenic mouse in which the Gs DREADD (rM3Ds), an engineered G protein-coupled receptor, is selectively expressed in striatopallidal medium spiny neurons (MSNs). We first show that in vitro, rM3Ds can couple to Gαolf and induce cAMP accumulation in cultured neurons and HEK-T cells. The rM3Ds was then selectively and stably expressed in striatopallidal neurons by creating a transgenic mouse in which an adenosine2A (adora2a) receptor-containing bacterial artificial chromosome was employed to drive rM3Ds expression. In the adora2A-rM3Ds mouse, activation of rM3Ds by clozapine-N-oxide (CNO) induces DARPP-32 phosphorylation, consistent with the known consequence of activation of endogenous striatal Gαs-coupled GPCRs. We then tested whether CNO administration would produce behavioral responses associated with striatopallidal Gs signaling and in this regard CNO dose-dependently decreases spontaneous locomotor activity and inhibits novelty induced locomotor activity. Last, we show that CNO prevented behavioral sensitization to amphetamine and increased AMPAR/NMDAR ratios in transgene-expressing neurons of the nucleus accumbens shell. These studies demonstrate the utility of adora2a-rM3Ds transgenic mice for the selective and noninvasive modulation of Gαs signaling in specific neuronal populations in vivo.This unique tool provides a new resource for elucidating the roles of striatopallidal MSN Gαs signaling in other neurobehavioral contexts.  相似文献   
994.
Objectives Obestatin and ghrelin, which are derived from the same gene, are observed to have opposite effects on weight status. The aims of this study were to compare obestatin concentrations in obese and normal‐weight children and to analyse the effect of weight loss on obestatin and ghrelin levels. Methods We examined anthropometrical markers and fasting serum obestatin, ghrelin, leptin, glucose and insulin concentrations in 44 obese children (mean age 11·2 years) before and after participating in a 1‐year outpatient obesity intervention programme based on a high‐carbohydrate, fat‐reduced diet and increased physical activity. Additionally, total ghrelin, obestatin and leptin levels were determined in 22 normal‐weight healthy children of similar age, gender and pubertal stage. Results Obestatin and leptin concentrations were significantly (P < 0·001) higher and ghrelin concentrations were significantly (P < 0·001) lower in obese children compared to nonobese children. In contrast to the 13 children without weight loss, substantial weight loss in 31 children led to a significant (P = 0·007) increase in obestatin and to a significant (P < 0·05) decrease in leptin and insulin concentrations, while ghrelin concentrations did not change significantly. Children with substantial weight loss demonstrated significantly (P = 0·009) lower obestatin and a tendency (P = 0·064) to higher ghrelin concentrations at baseline. Changes in insulin were not related to changes in ghrelin or obestatin. Conclusion The increase in obestatin and the decrease in ghrelin in obese children point towards an adaptation process of weight status. Weight reduction due to a long‐term lifestyle intervention resulted in an increase in obestatin levels.  相似文献   
995.
BACKGROUND Liver cancer is the fifth most common cancer and the second cause of cancerrelated deaths worldwide.Transarterial chemoembolization(TACE)is the best treatment of intermediate hepatocellular carcinoma(HCC).Doxorubicin is the most commonly used drug despite a low level of evidence.AIM To compare the objective response rate of idarubicin-based TACE(Ida-TACE)against doxorubicin-based TACE(Dox-TACE)in intermediate stage HCC.METHODS Between January 2012 and December 2014,all patients treated with TACE at our academic hospital were screened.Inclusion criteria were patients with Child-Pugh score A or B,a performance status below or equal to 1,and no prior TACE.Either lipiodol TACE or drug-eluting beads TACE could be performed with 10 mg of idarubicin or 50 mg of doxorubicin.Each patient treated with idarubicin was matched with two doxorubicin-treated patients.The TACE response was assessed by independent radiologists according to the mRECIST criteria.RESULTS Sixty patients were treated with doxorubicin and thirty with idarubicin.There were 93%and 87%of cirrhotic patients and 87%and 70%of Child-Pugh A in the doxorubicin and idarubicin groups,respectively.The median number of HCC per patient was two in both groups with 31%and 26%of single nodules in doxorubicin and idarubicin groups,respectively.Objective response rate after first TACE was 76.7%and 73.3%(P=0.797)with 41.7%and 40.0%complete response in doxorubicin and idarubicin groups,respectively.Progression-free survival was 7.7 mo in both groups,and liver transplant-free survival was 24.9 mo and 21.9 mo in doxorubicin and idarubicin groups,respectively.Safety profiles were similar in both groups,with grade 3-4 adverse events in 35%of Dox-TACE and 43%of Ida-TACEs.CONCLUSION Ida-TACE and Dox-TACE showed comparable results in terms of efficacy and safety.Ida-TACE may represent an interesting alternative to Dox-TACE in the management of patients with intermediate stage HCC.  相似文献   
996.

Background

The objective of this study was to investigate changes in active and passive biomechanical properties of the calf muscle–tendon unit induced by controlled ankle stretching in stroke survivors.

Methods

Ten stroke survivors with ankle spasticity/contracture and ten healthy control subjects received intervention of 60-min ankle stretching. Joint biomechanical properties including resistance torque, stiffness and index of hysteresis were evaluated pre- and post-intervention. Achilles tendon length was measured using ultrasonography. The force output of the triceps surae muscles was characterized via the torque–angle relationship, by stimulating the calf muscles at a controlled intensity across different ankle positions.

Findings

Compared to healthy controls, the ankle position corresponding to the peak torque of the stroke survivors was shifted towards plantar flexion (P < 0.001). Stroke survivors showed significantly higher resistance torques and joint stiffness (P < 0.05), and these higher resistances were reduced significantly after the stretching intervention, especially in dorsiflexion (P = 0.013). Stretching significantly improved the force output of the impaired calf muscles in stroke survivors under matched stimulations (P < 0.05). Ankle range of motion was also increased by stretching (P < 0.001).

Interpretation

At the joint level, repeated stretching loosened the ankle joint with increased passive joint range of motion and decreased joint stiffness. At the muscle–tendon level, repeated stretching improved calf muscle force output, which might be associated with decreased muscle fascicle stiffness, increased fascicle length and shortening of the Achilles tendon. The study provided evidence of improvement in muscle tendon properties through stretching intervention.  相似文献   
997.
Fluoxetine was given to five nonveteran patients with post-traumatic stress disorder (PTSD). The maximum doses ranged from 20 to 80 mg/day, and treatment was continued for between 8 and 32 weeks. In contrast to published reports of other drugs, which were noted to improve only the intrusive symptoms of PTSD, fluoxetine was associated with marked improvement of both intrusive and avoidant symptoms. Facilitative effects of fluoxetine were noted on trauma-focused psychotherapy in two adult victims of childhood sexual trauma. In part, these effects were related to modulating effects of the drug upon the intensity of core PTSD symptoms. Serotonergic drugs appear to hold promise for the treatment of PTSD.This work was conducted in the Departments of Psychiatry and Psychology, Duke University, Durham, N.C.  相似文献   
998.
Because the bony girdle of the pelvis protects the external iliac artery except where it enters the femoral canal, reports of blunt injury to this artery are rare. Emphasizing the importance of a thorough physical examination and judicious use of angiography, this case study discusses the diagnosis and treatment of an isolated external iliac artery injury rendered by a bicycle handlebar, a previously unreported cause of this type of injury.  相似文献   
999.
Late life is a period frequently marked by decline in personal health and heightened need for social support. Consequently, the social networks in which individuals are embedded assume an increasingly central role in the health and wellbeing of older adults. In the present article, I review the state of the literature on social networks and health in later life. By drawing on insights from the sociology of ageing and the life course, I address new developments and current challenges within the field. Chief among these developments and challenges is the recognition that the ageing process does not occur in a vacuum. Rather, individuals are consistently exposed to numerous changes to their social lives which have strong implications for current and future health outcomes. Upon highlighting the latest innovations within the field of networks and health, I conclude with useful directions for future research.  相似文献   
1000.
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