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411.
Ana-Catarina Pinho-Gomes Luis Azevedo Emma Copland Dexter Canoy Milad Nazarzadeh Rema Ramakrishnan Eivind Berge Johan Sundstrm Dipak Kotecha Mark Woodward Koon Teo Barry R. Davis John Chalmers Carl J. Pepine Kazem Rahimi 《PLoS medicine》2021,18(6)
BackgroundRandomised evidence on the efficacy of blood pressure (BP)-lowering treatment to reduce cardiovascular risk in patients with atrial fibrillation (AF) is limited. Therefore, this study aimed to compare the effects of BP-lowering drugs in patients with and without AF at baseline.Methods and findingsThe study was based on the resource provided by the Blood Pressure Lowering Treatment Trialists’ Collaboration (BPLTTC), in which individual participant data (IPD) were extracted from trials with over 1,000 patient-years of follow-up in each arm, and that had randomly assigned patients to different classes of BP-lowering drugs, BP-lowering drugs versus placebo, or more versus less intensive BP-lowering regimens. For this study, only trials that had collected information on AF status at baseline were included. The effects of BP-lowering treatment on a composite endpoint of major cardiovascular events (stroke, ischaemic heart disease or heart failure) according to AF status at baseline were estimated using fixed-effect one-stage IPD meta-analyses based on Cox proportional hazards models stratified by trial. Furthermore, to assess whether the associations between the intensity of BP reduction and cardiovascular outcomes are similar in those with and without AF at baseline, we used a meta-regression. From the full BPLTTC database, 28 trials (145,653 participants) were excluded because AF status at baseline was uncertain or unavailable. A total of 22 trials were included with 188,570 patients, of whom 13,266 (7%) had AF at baseline. Risk of bias assessment showed that 20 trials were at low risk of bias and 2 trials at moderate risk. Meta-regression showed that relative risk reductions were proportional to trial-level intensity of BP lowering in patients with and without AF at baseline. Over 4.5 years of median follow-up, a 5-mm Hg systolic BP (SBP) reduction lowered the risk of major cardiovascular events both in patients with AF (hazard ratio [HR] 0.91, 95% confidence interval [CI] 0.83 to 1.00) and in patients without AF at baseline (HR 0.91, 95% CI 0.88 to 0.93), with no difference between subgroups. There was no evidence for heterogeneity of treatment effects by baseline SBP or drug class in patients with AF at baseline. The findings of this study need to be interpreted in light of its potential limitations, such as the limited number of trials, limitation in ascertaining AF cases due to the nature of the arrhythmia and measuring BP in patients with AF.ConclusionsIn this meta-analysis, we found that BP-lowering treatment reduces the risk of major cardiovascular events similarly in individuals with and without AF. Pharmacological BP lowering for prevention of cardiovascular events should be recommended in patients with AF.In an individual patient data meta-analysis, Ana-Catarina Pinho-Gomes and colleagues investigate prevention of cardiovascular events with blood pressure-lowering treatment in those with and without atrial fibrillation. 相似文献
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Manjula S. N. Chandrasekhar M. Ramachandra Naik Revathi V. Nagabhushana H. Ravikumar C. R. Surendra B. S. Naveen kumar A. 《Luminescence》2023,38(7):1149-1166
A low temperature-assisted and oxalyl dihydrazide fuel-induced combustion synthesized series of uncalcined MgAl2O4:Eu3+ nanophosphors showed an average crystallite size of ~20 nm, and bandgap energy (Eg) of 4.50–5.15 eV, and were validated using density functional theory and found to match closely with the experimental values. The photoluminescence characteristic emission peaks of Eu3+ ions were recorded between 480 and 680 nm. The nanophosphors excited at 392 nm showed f–f transitions assigned as 5D0→7FJ (J = 0, 1, 2, and 3). The optimized MgAl2O4 phosphors had Commission Internationale de l'Eclairage coordinates in the red region, a correlated colour temperature of 2060 K, and a colour purity of 98.83%. The estimated luminescence quantum efficiency ( ) was observed to be ~63% using Judd–Ofelt analysis. Electrochemical and photocatalytic performance were explored and indicated its multifunctional applications. Therefore, MgAl2O4:Eu3+ nanophosphors could be used for the fabrication of light-emitting diodes, industrial dye degradation, and as electrodes for supercapacitor applications. 相似文献
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Tammineni Venkata Surendra Selvaraj Mohana Roopan Maksudur R. Khan 《Biotechnology progress》2019,35(4):e2823
The rare earth metal oxide nanoparticles such as gadolinium oxide nanoparticles (Gd2O3 NPs) have been synthesized by green synthesis process using methanolic extract of Moringa oleifera (M oleifera) peel. In this process, the Gd2O3 NPs formation was observed at 280–300 nm in UV–Vis spectroscopy. The XRD pattern of the synthesized Gd2O3 NPs was exactly matched with JCPDS No 3-065-3181which confirms the crystalline nature of Gd2O3 NPs. In addition, Energy-dispersive X-ray spectroscopy (EDX) analysis was stated that Gd and O elements were present as 70.31 and 29.69%, respectively in Gd2O3 NPs. The SEM and TEM analysis were said Gd2O3 NPs are in rod shape and 26 ± 2 nm in size. Further the synthesized Gd2O3 NPs were confirmed by X-ray photoemission spectroscopy (XPS). The synthesized Gd2O3 NPs were further examined for anti-fungal activity against Alternaria saloni (A saloni) and Sclerrotium rolfsii (S rolfsii) and it showed moderate activity. Also, Gd2O3 NPs evaluated as good antibacterial agent against different Gram +ve and Gram −ve bacteria. Moreover, the toxicity of the Gd2O3 NPs on red blood cells (RBCs) of the human blood was determined using hemolytic assay, the obtained results were stated the synthesized Gd2O3 NPs are nontoxic to the human erythrocytes. The photocatalytic activity against malachite green (MG) dye was tested and confirmed as 92% of dye was degraded within 2 hr by Gd2O3 NPs. The results were stated the green synthesized Gd2O3 NPs are good anti-fungal agents, nontoxic and we can use as a photocatalyst. Copyright © 2019 John Wiley & Sons, Ltd. 相似文献
416.
Jaya Shree Rajesh Choudhary Surendra H Bodakhe 《Journal of biochemical and molecular toxicology》2019,33(8)
The ocular renin‐angiotensin system has become an interesting target for ocular diseases because it has been implicated in various ocular diseases such as diabetic retinopathy, glaucoma, age‐related macular degeneration, uveitis, and hypertensive cataracts. In the present study, we explored the effect of topically and orally administered losartan (an angiotensin receptor blocker) on streptozotocin‐induced diabetic cataract in albino rats. Topical treatment with losartan modulated neither the blood glucose level nor the polyol content but oral treatment with losartan decreased both. Topical and oral treatment with losartan significantly increased the antioxidants (glutathione, glutathione peroxidase, superoxide dismutase, and catalase), decreased the lipid peroxidant malondialdehyde, and restored soluble protein, and insoluble protein and various ions (Na+, K+, and Ca2+) in the lens; however, topical treatment had a better effect than oral treatment. These findings demonstrate that topical administration of losartan significantly reduces the risk of cataract formation without affecting either the blood glucose level or polyol contents. 相似文献
417.