383 research outputs found
The IPHAS catalogue of H alpha emission-line sources in the northern Galactic plane
No full textWe present a catalogue of point-source H alpha emission-line objects selected from the INT/WFC Photometric Ha Survey (IPHAS) of the northern Galactic plane. The catalogue covers the magnitude range 13 <= r' <= 19.5 and includes Northern hemisphere sources in the Galactic latitude range -5 degrees < b < 5 degrees. It is derived from similar to 1500 deg(2) worth of imaging data, which represents 80 per cent of the final IPHAS survey area. The electronic version of the catalogue will be updated once the full survey data become available. In total, the present catalogue contains 4853 point sources that exhibit strong photometric evidence for Ha emission. We have so far analysed spectra for similar to 300 of these sources, confirming more than 95 per cent of them as genuine emission-line stars. A wide range of stellar populations are represented in the catalogue, including early-type emission-line stars, active late-type stars, interacting binaries, young stellar objects and compact nebulae.
The spatial distribution of catalogue objects shows overdensities near sites of recent or current star formation, as well as possible evidence for the warp of the Galactic plane. Photometrically, the incidence of Ha emission is bimodally distributed in (r' - i'). The blue peak is made up mostly of early-type emission-line stars, whereas the red peak may signal an increasing contribution from other objects, such as young/active low-mass stars. We have cross-matched our H alpha-excess catalogue against the emission-line star catalogue of Kohoutek & Wehmeyer, as well as against sources in SIMBAD. We find that fewer than 10 per cent of our sources can be matched to known objects of any type. Thus IPHAS is uncovering an order of magnitude more faint (r' > 13) emission-line objects than were previously known in the Milky Way
Interventions to achieve long-term weight loss in obese older people
No full textThis is a pre-copy-editing, author-produced PDF of an article accepted for publication in Age and Ageing following peer review. The definitive publisher-authenticated version Witham, M. & Avenell, A. (2010). 'Interventions to achieve long-term weight loss in obese older people.' Age and Ageing 39(2) pp. 176-184 is available online at: http://dx.doi.org/10.1093/ageing/afp251.Peer reviewe
Vitamin D in chronic heart failure
No full textRecent evidence suggests a number of mechanisms whereby vitamin D may positively influence the pathophysiology of heart failure. These include actions on the renin-angiotensin system, calcium handling, reduction of proinflammatory cytokines, and improvements in endothelial function and blood pressure. Observational data suggest that low vitamin D levels are common in patients with heart failure and are associated with worse exercise capacity and natriuretic peptide levels. Little interventional data are currently available, but evidence to date does not support vitamin D supplementation, even in patients with low vitamin D levels. Further studies are needed to establish whether larger doses of vitamin D given over a longer period of time can reduce symptoms, hospitalization, and mortality in heart failure
Does oral sodium bicarbonate therapy improve function and quality of life in older patients with chronic kidney disease and low-grade acidosis (the BiCARB trial)? : Study protocol for a randomized controlled trial
No full textDate of acceptance: 01/07/2015 © 2015 Witham et al. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Acknowledgements UK NIHR HTA grant 10/71/01. We acknowledge the financial support of NHS Research Scotland in conducting this trial.Peer reviewe
Effect of vitamin D supplementation on blood pressure:a systematic review and meta-analysis incorporating individual patient data
No full textImportance Low levels of vitamin D are associated with elevated blood pressure (BP) and future cardiovascular events. Whether vitamin D supplementation reduces BP and which patient characteristics predict a response remain unclear.Objective To systematically review whether supplementation with vitamin D or its analogues reduce BP.Data Sources We searched MEDLINE, CINAHL, EMBASE, Cochrane Central Register of Controlled Trials, and http://www.ClinicalTrials.com augmented by a hand search of references from the included articles and previous reviews. Google was searched for gray literature (ie, material not published in recognized scientific journals). No language restrictions were applied. The search period spanned January 1, 1966, through March 31, 2014.Study Selection We included randomized placebo-controlled clinical trials that used vitamin D supplementation for a minimum of 4 weeks for any indication and reported BP data. Studies were included if they used active or inactive forms of vitamin D or vitamin D analogues. Cointerventions were permitted if identical in all treatment arms.Data Extraction and Synthesis We extracted data on baseline demographics, 25-hydroxyvitamin D levels, systolic and diastolic BP (SBP and DBP), and change in BP from baseline to the final follow-up. Individual patient data on age, sex, medication use, diabetes mellitus, baseline and follow-up BP, and 25-hydroxyvitamin D levels were requested from the authors of the included studies. For trial-level data, between-group differences in BP change were combined in a random-effects model. For individual patient data, between-group differences in BP at the final follow up, adjusted for baseline BP, were calculated before combining in a random-effects model.Main Outcomes and Measures Difference in SBP and DBP measured in an office setting.Results We included 46 trials (4541 participants) in the trial-level meta-analysis. Individual patient data were obtained for 27 trials (3092 participants). At the trial level, no effect of vitamin D supplementation was seen on SBP (effect size, 0.0 [95% CI, −0.8 to 0.8] mm Hg; P = .97; I2 = 21%) or DBP (effect size, −0.1 [95% CI, −0.6 to 0.5] mm Hg; P = .84; I2 = 20%). Similar results were found analyzing individual patient data for SBP (effect size, −0.5 [95% CI, −1.3 to 0.4] mm Hg; P = .27; I2 = 0%) and DBP (effect size, 0.2 [95% CI, −0.3 to 0.7] mm Hg; P = .38; I2 = 0%). Subgroup analysis did not reveal any baseline factor predictive of a better response to therapy.Conclusions and Relevance Vitamin D supplementation is ineffective as an agent for lowering BP and thus should not be used as an antihypertensive agent.<br/
Growing research in geriatric medicine
No full text© 2019 The Author(s). Academic geriatric medicine activity lags behind the scale of clinical activity in the specialty. A meeting of UK academic geriatricians was convened in March 2018 to consider causes and solutions to this problem. The meeting highlighted a lack of research-Active clinicians, a perception that research is not central to the practice of geriatric medicine and a failure to translate discovery science to clinical studies. Solutions proposed included better support for early-career clinical researchers, schemes to encourage non-University clinicians to be research-Active, wider collaboration with organ specialists to broaden the funding envelope, and the need to co-produce research programmes with end-users. Solutions to grow academic geriatric medicine are essential if we are to provide the best care for the growing older population
Controversy in the link between Vitamin D supplementation and hypertension
No full textVitamin D affects a range of pathophysiological processes pertinent to the control of blood pressure, including endothelial function, inflammation and renin-angiotensin system activity. Observational data show a clear relationship between 25-hydroxyvitamin D levels and both current blood pressure and incident hypertension. However, recent trial data have shown no significant effect of vitamin D supplementation on blood pressure, even at high doses, low vitamin D levels and in patients with high baseline blood pressure. Vitamin D might still benefit cardiovascular health through mechanisms other than blood pressure reduction, but data from large trials are required to show this. In the meantime, vitamin D has no place in controlling blood pressure either at the individual or the population level.</p
Vitamin D and Cardiovascular Prevention
No full textVitamin D has been known to medical science for almost a century. Yet, it is only in the last 15 years that we have realized that the biological effects of vitamin D extend far beyond the control of calcium metabolism. Recent observational evidence suggests strong links between low vitamin D levels and a range of cardiovascular conditions, including stroke, myocardial infarction, hypertension, and diabetes. Interventional studies are beginning to explore whether vitamin D supplementation can modify vascular health and prevent cardiovascular disease. This article reviews the physiology and function of vitamin D, examines the current observational and intervention data in cardiovascular disease, and discusses future research and current practice recommendations.</p
Effect of vitamin D on blood pressure: a systematic review and meta-analysis
No full textObjectives Vitamin D insufficiency has been linked to hypertension and cardiovascular events in observational studies. It is unclear whether vitamin D supplementation can reduce blood pressure, and, if so, by how much.Methods We performed a systematic review and meta-analysis to examine whether vitamin D reduces blood pressure. Databases including MEDLINE, EMBASE, the Cumulative Index to Nursing and Allied Health Literature and the Cochrane library were searched, supplemented by searches of grey literature, unpublished trials and references from included studies. Studies were assessed by two reviewers independently according to a prespecified protocol. Interventions included activated vitamin D, unactivated vitamin D2 and D3 and ultraviolet B radiation.Results Eleven randomized, controlled trials fulfilled the inclusion criteria. Studies were small and of variable methodological quality. Mean baseline blood pressure was more than 140/90 mmHg in eight studies. Meta-analysis of these eight studies showed a nonsignificant reduction in systolic blood pressure in the vitamin D group compared with placebo [-3.6mmHg, 95% confidence interval (CI) -8.0 to 0.7]. A small, statistically significant reduction was seen in diastolic blood pressure (-3.1mmHg, 95% CI -5.5 to -0.6). Subgroup analysis suggested that unactivated vitamin D produced a greater fall in systolic blood pressure than activated vitamin D (-6.2mmHg, 95% CI -12.32 to -0.04, vs. +0.7 mmHg, 95% CI -4.8 to 6.2). No reduction in blood pressure was seen in studies examining patients who were normotensive at baseline.Conclusion We found weak evidence to support a small effect of vitamin D on blood pressure in studies of hypertensive patients. J Hypertens 27: 1948-1954 (C) 2009 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.</p
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