Tracking of sport and exercise types from midlife to old age: a 20-year cohort study of British men.

Background: Previous physical activity (PA) tracking studies have examined the stability of overall PA and/or PA types, but few have investigated how specific types of sport/exercise track over the life course. The aim of this study was to determine how specific sports/exercises in midlife track and predict future sport/exercise and PA in men transitioning to old age. Methods: Seven thousand seven hundred thirty-five men (aged 40-59 years) recruited in 1978-80 were followed up after 12, 16 and 20 years. At each wave men self-reported participation in sport/exercise. Frequent sport/exercise participants (> 1/month) reported the types of sport/exercise they engaged in. Men also reported total PA, health status, lifestyle behaviours and socio-demographic characteristics. Stability of each sport/exercise was assessed using kappa statistics and intraclass correlation coefficients. Logistic regression estimated the odds of participating in sport/exercise and being active at 20-year follow up according to specific types of sport/exercise in midlife. Results: Three thousand three hundred eighty-four men with complete data at all waves were included in analyses. Tracking of specific sports/exercises ranged from fair to substantial, with golf being the most common and most stable. Bowls was the most frequently adopted. Odds of participating in sport/exercise and being active in old age varied according to sport/exercise types in midlife. Golf and bowls in midlife were the strongest predictors of sport/exercise participation in old age. Golf, cricket and running/jogging in midlife were among the strongest predictors of being active in old age. Compared to participating in just one sport/exercise in midlife, sampling multiple sports/exercises was more strongly associated with sport/exercise participation and being active in old age. Conclusion: The stability of sport/exercise participation from midlife to old age varies by type. Specific sports/exercises in midlife may be more likely to predict future PA than others. However, participating in a range of sports/exercises may be optimal for preserving PA into old age

Effects of reallocating time in different activity intensities on health and fitness: a cross sectional study

BACKGROUND: The effects of replacing time in specific activity categories for other categories (e.g. replacing sedentary time with light activity) on health and fitness are not well known. This study used isotemporal substitution to investigate the effects of substituting activity categories in an equal time exchange fashion on health and fitness in young people. METHODS: Participants were drawn from schools in Camden, London (n = 353, mean age 9.3 ± 2.3 years). Time sedentary, in light and in moderate-to-vigorous activity (MVPA) was measured via accelerometry. The effects of substituting time in activity categories (sedentary, light and MVPA) with equivalent time in another category on health and fitness were examined using isotemporal substitution. RESULTS: In single and partition models, MVPA was favourably associated with body fat %, horizontal jump distance and flexibility. Time sedentary and in light activity were not associated with health and fitness outcomes in these models. In substitution models, replacing one hour of sedentary time with MVPA was favourably associated with body fat % (B = -4.187; 95% confidence interval (CI), -7.233, -1.142), horizontal jump distance (B = 16.093; 95% CI, 7.476, 24.710) and flexibility (B = 4.783; 95% CI, 1.910, 7.656). Replacing time in light activity with MVPA induced similar benefits but there were null effects for replacing sedentary with light intensity. CONCLUSION: Substituting time sedentary and in light activity with MVPA was associated with favourable health and fitness. Time in sedentary behaviour may only be detrimental to health and fitness when it replaces time in MVPA in young people

Camden active spaces: does the construction of active school playgrounds influence children's physical activity levels? A longitudinal quasi-experiment protocol.

Physical activity is essential for every facet of children's health. However, physical activity levels in British children are low. The school environment is a promising setting to increase children's physical activity but limited empirical evidence exists on how a change in the outdoor physical school environment influences physical activity behaviour. The London Borough of Camden is redesigning seven existing school playgrounds to engage children to become more physically active. The primary aim of this project is to evaluate the impact of the redesigned playgrounds on children's physical activity, well-being and physical function/fitness

Decrease in plasma miR-27a and miR-221 after concussion in Australian football players

Introduction: Sports-related concussion (SRC) is a common form of brain injury that lacks reliable methods to guide clinical decisions. MicroRNAs (miRNAs) can influence biological processes involved in SRC, and measurement of miRNAs in biological fluids may provide objective diagnostic and return to play/recovery biomarkers. Therefore, this prospective study investigated the temporal profile of circulating miRNA levels in concussed male and female athletes. Methods: Pre-season baseline blood samples were collected from amateur Australian rules football players (82 males, 45 females). Of these, 20 males and 8 females sustained an SRC during the subsequent season and underwent blood sampling at 2-, 6- and 13-days post-injury. A miRNA discovery Open Array was conducted on plasma to assess the expression of 754 known/validated miRNAs. miRNA target identified were further investigated with quantitative real-time PCR (qRT-PCR) in a validation study. Data pertaining to SRC symptoms, demographics, sporting history, education history and concussion history were also collected. Results: Discovery analysis identified 18 candidate miRNA. The consequent validation study found that plasma miR-221-3p levels were decreased at 6d and 13d, and that miR-27a-3p levels were decreased at 6d, when compared to baseline. Moreover, miR-27a and miR-221-3p levels were inversely correlated with SRC symptom severity. Conclusion: Circulating levels of miR-27a-3p and miR-221-3p were decreased in the sub-acute stages after SRC, and were inversely correlated with SRC symptom severity. Although further studies are required, these analyses have identified miRNA biomarker candidates of SRC severity and recovery that may one day assist in its clinical management

Intravitreal bevacizumab (Avastin®) for diabetic retinopathy at 24-months: The 2008 Juan Verdaguer-planas lecture

Diabetic retinopathy (DR) remains the major threat to sight in the working age population. Diabetic macular edema (DME) is a manifestation of DR that produces loss of central vision. Proliferative diabetic retinopathy (PDR) is a major cause of visual loss in diabetic patients. In PDR, the growth of new vessels is thought to occur as a result of vascular endothelial growth factor (VEGF) release into the vitreous cavity as a response to ischemia. Furthermore, VEGF increases vessel permeability leading to deposition of proteins in the interstitium that facilitate the process of angiogenesis and macular edema. This review demonstrates multiple benefits of intravitreal bevacizumab (IVB) on DR including DME and PDR at 24 months of follow up. The results indicate that IVB injections may have a beneficial effect on macular thickness and visual acuity (VA) in diffuse diabetic macular edema. Therefore, in the future this new therapy could replace or complement focal/grid laser photocoagulation in DME. In PDR, this new option could be an adjuvant agent to pan-retina photocoagulation so that more selective therapy may be applied. In addition, we report a series of patients in which tractional retinal detachment developed or progressed after adjuvant preoperative IVB in severe PDR. © 2010 Bentham Science Publishers Ltd

Contribution of NK3 tachykinin receptors to propulsion in the rabbit isolated distal colon

The role of NK3 receptors in rabbit colonic propulsion has been investigated in vitro with the selective agonist, senktide, and two selective antagonists, SR142801 and SB222200. Peristalsis was elicited by distending a rubber balloon with 0.3 and 1.0 mL of water leading to a velocity of 2.2 and 2.8 mm s(-1), respectively. At concentrations of 1 nM, senktide inhibited propulsion evoked by both distensions (range 25-40%), whereas at 6 and 60 nmol L-1 facilitated 'submaximal' propulsion by 30%. In the presence of N omega -nitro-L-arginine (L-NNA, 200 mu mol L-1), which per se caused a slight prokinetic effect, 1 nmol L-1 senktide markedly accelerated propulsion (range 35-50%). Hexamethonium (200 mu mol L-1) had minor effects on propulsion. In its presence, 60 nmol L-1 senktide significantly inhibited propulsion induced by both stimuli (range 20-50%). SR142801 (0.3, 3 nmol L-1) and SB222200 (30, 300 nmol L-1) facilitated 'submaximal' propulsion (range 20-40%). Conversely, higher antagonist concentrations (SR142801: 30, 300 nM; SB222200: 1, 10 mu mol L-1) inhibited propulsion to both distensions by 20%. A combination of SR142801 (300 nmol L-1) plus hexamethonium (200 mu mol L-1) induced an approximately four-fold greater inhibition of propulsion than that induced by SR142801 alone. In conclusion, in the rabbit-isolated distal colon, a subset of NK3 receptors located on descending pathways mediates an inhibitory effect on propulsion by activating a NO-dependent mechanism. Another subset of NK3 receptors, located on ascen ding pathways mediates a facilitative effect involving a synergistic interaction with cholinergic nicotinic receptors

Grey and white matter structure associates with the activation of the tryptophan to kynurenine pathway in bipolar disorder

Background: Bipolar disorder (BD) is a severe mental illness characterised by reduced grey matter (GM) volumes and cortical thickness, and disrupted white matter (WM) microstructure. Activation of indoleamine 2,3-dioxygenase following a pro-inflammatory state could increase the amount of tryptophan (Trp) converted to kynurenine (Kyn) possibly leading to the production of detrimental catabolites of the Kyn pathway with neurotoxic effects. We investigated if peripheral levels of Trp-and Kyn and the breakdown of Trp-into Kyn (Kyn/Trp-ratio) are related to WM and GM integrity in BD. Methods: Peripheral levels of Trp-and Kyn were analysed in 72 patients with BD and 33 controls. Patients also underwent MRI in a Philips 3T scanner. Results: Patients showed higher Kyn levels and Kyn/Trp-ratio compared to controls. MRI analyses performed in patients with BD showed a negative association between the Kyn/Trp-ratio and the integrity of corpus callosum microstructure, the volume of the amygdala and cortical thickness in fronto-parietal regions. Limitation: The lack of information on the levels of downstream metabolites of Kyn prevent us to confirm the possible unbalance between quinolinic and kynurenic acids as well as their possible relationship with changes in GM and WM markers. The activation of the Kyn pathway as suggested by the increased Kyn/Trp-ratio may lead to an imbalance of the neurotoxic vs the neuroprotective arm of the biochemical pathway, resulting in significant changes in GM and WM regions of brain areas strongly implicated in the pathophysiology of BD, such as amygdala and corpus callosum