17 research outputs found

    Further investigation of mental tris-quinolates using spectroscopy

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    Structure of aluminum tris-8-hydroxyquinoline (Alq3) and other metal tris-quinolates (Mq3) in vapor deposited films in organic light emitting devices (OLEDs) is not well established due to the possibility of existing two geometric isomeric forms, meridianal and facial. We present a comparative analysis of 1H and 13C NMR of nMeq3M\u27s (n = 0, 2, 4, 5) made from thermal sublimation, in a polar as well as a non-polar solvent to investigate possible evidences for the isomer distribution, stability of the metal chelate in the presence of a polar solvent and crystal structure determination for pure Inq 3 using single-crystal x-ray diffraction studies. This work will be the first report to use 13C NMR spectroscopy to investigate nMeq3M\u27s (n = 0, 2, 4, 5). These metal chelates were found to be stable in the presence of a polar solvent and the results were shown to support the mer-isomer. Also in this work the first report of the crystal structure for Inq3 grown in gas phase is reported and it was found to have a mer-configuration

    Metabolic Modulation Predicts Heart Failure Tests Performance

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    The metabolic changes that accompany changes in Cardiopulmonary testing (CPET) and heart failure biomarkers (HFbio) are not well known. We undertook metabolomic and lipidomic phenotyping of a cohort of heart failure (HF) patients and utilized Multiple Regression Analysis (MRA) to identify associations to CPET and HFBio test performance (peak oxygen consumption (Peak VO2), oxygen uptake efficiency slope (OUES), exercise duration, and minute ventilation-carbon dioxide production slope (VE/VCO2 slope), as well as the established HF biomarkers of inflammation C-reactive protein (CRP), beta-galactoside-binding protein (galectin-3), and N-terminal prohormone of brain natriuretic peptide (NT-proBNP)). A cohort of 49 patients with a left ventricular ejection fraction \u3c 50%, predominantly males African American, presenting a high frequency of diabetes, hyperlipidemia, and hypertension were used in the study. MRA revealed that metabolic models for VE/VCO2 and Peak VO2 were the most fitted models, and the highest predictors’ coefficients were from Acylcarnitine C18:2, palmitic acid, citric acid, asparagine, and 3-hydroxybutiric acid. Metabolic Pathway Analysis (MetPA) used predictors to identify the most relevant metabolic pathways associated to the study, aminoacyl-tRNA and amino acid biosynthesis, amino acid metabolism, nitrogen metabolism, pantothenate and CoA biosynthesis, sphingolipid and glycerolipid metabolism, fatty acid biosynthesis, glutathione metabolism, and pentose phosphate pathway (PPP). Metabolite Set Enrichment Analysis (MSEA) found associations of our findings with pre-existing biological knowledge from studies of human plasma metabolism as brain dysfunction and enzyme deficiencies associated with lactic acidosis. Our results indicate a profile of oxidative stress, lactic acidosis, and metabolic syndrome coupled with mitochondria dysfunction in patients with HF tests poor performance. The insights resulting from this study coincides with what has previously been discussed in existing literature thereby supporting the validity of our findings while at the same time characterizing the metabolic underpinning of CPET and HFBio

    Molecular Predictors of Anakinra Treatment Success in Heart Failure Patients with Reduced Ejection Fraction

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    Background. Kineret (Anakinra) is an interleukin-1 antagonist that is under investigation for its novel clinical application treating patients that have heart failure with reduced (\u3c50%) ejection fraction (HFrEF). A prior study from our group indicated that Anakinra may restore heart function by addressing dysregulations in HFrEF metabolic pathways. Herein, we attempt to elicit Anakinra’s effects on both metabolome and lipidome. Methods. Lipids and metabolites that had previously been quantified by mass spectrometry (MS) from patients (n=49) who had ≥2 mg/L of high-sensitivity C-reactive protein (hs-CRP) were mTIC normalized and transformed. We conducted a stepwise Linear Discriminant Analysis (r- LDA) to test Anakinra (2 and 12 weeks) vs placebo for separation from combined baseline. Metabolic pathway analysis was performed with Fisher’s exact test algorithm for detection of over-represented and enriched analytes. Univariate analysis (one tailed t-test p\u3c0.05) compared placebo and Anakinra after 12-weeks for effect(s). Metaboanalyst 4.0, JMP Pro 14.0, and a proprietary package in R (version 3.4.4) were the software for all analyses and data wrangling. Results. Analytes such as acylcarnitines C10:0 and C16:0 and hsCRP showed significant improvements after 12 weeks of Anakinra, leading to improved mitochondrial function, reduced inflammation, and overall better health outcomes. Statistically significant (p\u3c0.05) pathways including the citrate cycle, cysteine and methionine metabolism, galactose metabolism among others were associated with treatment. Conclusions. We were able to determine significant alterations to metabolomic and lipidomic concentrations after 12 weeks of Anakinra therapy. Our biochemical analyses verifies that Anakinra did improve heart function within our HFrEF pilot cohort.https://scholarscompass.vcu.edu/gradposters/1081/thumbnail.jp

    A community-based cluster randomised trial of safe storage to reduce pesticide self-poisoning in rural Sri Lanka: study protocol

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    BACKGROUND: The WHO recognises pesticide poisoning to be the single most important means of suicide globally. Pesticide self-poisoning is a major public health and clinical problem in rural Asia, where it has led to case fatality ratios 20-30 times higher than self-poisoning in the developed world. One approach to reducing access to pesticides is for households to store pesticides in lockable "safe-storage" containers. However, before this approach can be promoted, evidence is required on its effectiveness and safety. METHODS/DESIGN: A community-based cluster randomised controlled trial has been set up in 44,000 households in the North Central Province, Sri Lanka. A census is being performed, collecting baseline demographic data, socio-economic status, pesticide usage, self-harm and alcohol. Participating villages are then randomised and eligible households in the intervention arm given a lockable safe storage container for agrochemicals. The primary outcome will be incidence of pesticide self-poisoning over three years amongst individuals aged 14 years and over. 217,944 person years of follow-up are required in each arm to detect a 33% reduction in pesticide self-poisoning with 80% power at the 5% significance level. Secondary outcomes will include the incidence of all pesticide poisoning and total self-harm. DISCUSSION: This paper describes a large effectiveness study of a community intervention to reduce the burden of intentional poisoning in rural Sri Lanka. The study builds on a strong partnership between provincial health services, local and international researchers, and local communities. We discuss issues in relation to randomisation and contamination, engaging control villages, the intervention, and strategies to improve adherence

    The global burden of cancer attributable to risk factors, 2010-19 : a systematic analysis for the Global Burden of Disease Study 2019

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    Background Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. Methods The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk-outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. Findings Globally, in 2019, the risk factors included in this analysis accounted for 4.45 million (95% uncertainty interval 4.01-4.94) deaths and 105 million (95.0-116) DALYs for both sexes combined, representing 44.4% (41.3-48.4) of all cancer deaths and 42.0% (39.1-45.6) of all DALYs. There were 2.88 million (2.60-3.18) risk-attributable cancer deaths in males (50.6% [47.8-54.1] of all male cancer deaths) and 1.58 million (1.36-1.84) risk-attributable cancer deaths in females (36.3% [32.5-41.3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20.4% (12.6-28.4) and DALYs by 16.8% (8.8-25.0), with the greatest percentage increase in metabolic risks (34.7% [27.9-42.8] and 33.3% [25.8-42.0]). Interpretation The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe

    Efficient electrocatalyst utilization: electrochemical deposition of Pt nanoparticles using nafion membrane as a template

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    We deposit Pt particles electrochemically on an electrode covered with a Nation membrane. Platinum ions travel through the hydrophilic channels of the membrane, and platinum deposits are formed at the place where the channels make contact with the planar electrode. This procedure deposits the catalyst only at the end of the hydrophilic channels that cross the membrane; no catalyst is placed under the hydrophobic domains, where it would not be in contact with the electrolyte. By performing a series of cyclic voltammograms with this system, we show that deposition of the platinum through the membrane achieves better platinum utilization than deposition of platinum on the naked electrode followed by the placement of the membrane on top

    Heavy metal contamination in surface sediments of major tanks in Anuradhapura district; A CKDu endemic district in Sri Lanka

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    Farming occupants are the major victims of Chronic Kidney Disease of unknown etiology (CKDu) in North Central region, Sri Lanka. Tanks are the main source of water for farming and they act as sinks for agricultural run-offs. Environmental toxicants are adsorbed by bottom sediments and can be released into the adjacent water column due to environmental changes as those are not permanently bound. Therefore, this study attempts to determine the contamination situation of the selected toxic metals in sediments of the tanks in a CKDu prevalence distrct (Anuradhapura) in Sri Lanka and prediction of the risk. Sixteen tanks were selected and sediment samples were randomly collected from each tank from bank to center. Digested sediment samples were analyzed for heavy metals using Inductive Couple Plasma Mass Spectrometry and Calcium and Magnesium contents were analyzed using Atomic Absorption Spectrometry. According to the statistics, average values of some toxic metals such as As Pb, and Cr in sediments were higher than severe effect levels (SEL) while most of the mean values of Cd, As, Pb, Cr, Zn, and Cu  were beyond the Lowest effect levels (LEL). Apart from that, Geo Accumulation Indexes (Igeo) Indicate that almost all tanks in Anuradhapura district have moderately polluted with above mentioned pollutants. Hence, findings reveal about a risk generated on aquatic lives in the tanks as well as humans via food chain contamination with hazardous metals

    Phosphine Oxide Containing Poly(pyridinium salt)s as Fire Retardant Materials

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    Six new rugged, high-temperature tolerant phosphine oxide-containing poly(4,4′-(p-phenylene)-bis(2,6-diphenylpyridinium)) polymers P-1, P-2, P-3, P-4, P-5, and P-6 are synthesized, characterized, and evaluated. Synthesis results in high yield and purity, as confirmed by elemental, proton (1H), and carbon 13 (13C) nuclear magnetic resonance (NMR) spectra analyses. High glass transition temperatures (Tg > 230 °C) and high char yields (>50% at 700 °C) are determined by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. These new ionic polymers exhibit excellent processability, thin-film forming, high-temperature resistance, fire-resistance and retardation, coating, adhesion, mechanical and tensile strength, and n-type (electron transport) properties. The incorporation of phosphine oxide and bis(phenylpyridinium) moieties in the polymer backbones leads to high glass transition temperatures and excellent fire retardant properties, as determined by microcalorimetry measurements. The use of organic counterions allows these ionic polymers to be easily processable from several common organic solvents. A large variety of these polymers can be synthesized by utilizing structural variants of the bispyrylium salt, phosphine oxide containing diamine, and the counterion in a combinatorial fashion. These results make them very attractive for a number of applications, including as coating and structural component materials for automobiles, aircrafts, power and propulsion systems, firefighter garments, printed circuit boards, cabinets and housings for electronic and electrical components, construction materials, mattresses, carpets, upholstery and furniture, and paper-thin coatings for protecting important paper documents

    Investigation of the enhanced signals from cations and dopamine in electrochemical sensors coated with Nafion

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    An electrochemical sensor for the detection of dopamine (DA) was designed using a modified Nafion membrane on a glassy carbon electrode. The electrochemical signals from dopamine were enhanced more than 10-fold on a Nafion membrane coated electrode relative to a bare electrode. The hypothesis that the origin of the signal enhancement was due to the accumulation of cationic dopamine in the Nafion was tested using Pd ions as an analog which undergo a two electron reduction similar to dopamine. Electroless deposition of palladium was used to deposit palladium on a highly oriented pyrolytic graphite surface with and without the Nafion membrane. Using scanning electron microscopy (SEM) significantly greater deposits of metallic Pd were observed on the Nafion coated surfaces than in the absence of Nafion and energy dispersive X-ray spectroscopy (EDS) confirmed quantitatively greater Pd deposition on the Nafion coated surfaces
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