266 research outputs found

    The preparation and characterisation of microplastics containing contaminants

    Get PDF
    Alexandra Gulizia studied the behaviours of microplastics in the environment. By investigating their degradative susceptibility, reactive properties, leaching dynamics and relationship with the microbiome, she was able to deconstruct the complexity of microplastics in aqueous matrices to improve technical accuracy for future experiments and environmental risk assessments

    Inhibition of RNA polymerase II transcription in human cells by synthetic DNA-binding ligands

    Get PDF
    Sequence-specific DNA-binding small molecules that can permeate human cells potentially could regulate transcription of specific genes. Multiple cellular DNA-binding transcription factors are required by HIV type 1 for RNA synthesis. Two pyrrole-imidazole polyamides were designed to bind DNA sequences immediately adjacent to binding sites for the transcription factors Ets-l, lymphoid-enhancer binding factor 1, and TATA-box binding protein. These synthetic ligands specifically inhibit DNA-binding of each transcription factor and HIV type 1 transcription in cell-free assays. When used in combination, the polyamides inhibit virus replication by >99% in isolated human peripheral blood lymphocytes, with no detectable cell toxicity, The ability of small molecules to target predetermined DNA sequences located within RNA polymerase II promoters suggests a general approach for regulation of gene expression, as well as a mechanism for the inhibition of viral replication

    Copper Based Bi-metallic Core Pin Using DMD: Industrial Evaluation

    Get PDF
    Bi-metallic core pins were prepared and the performance was evaluated in a specially designed die that had the provision to investigate core pins under semi-industrial HPDC conditions. A comparison between bi-metallic core pin with that of tool steel revealed that bi-metallic core pin performed better in terms of soldering under HPDC environment. Due to slow cooling, die holding time needed to be increased in tool steel core pin to allow sufficient solidification of the casting part. The bi-metallic core pins also operated without any catastrophic failure in the clad which particularly substantiated the applicability of DMD deposited tool steel clad on copper alloy substrate to manufacture bi-metallic tooling

    Prevalence and pharmacologic management of familial hypercholesterolemia in an unselected contemporary cohort of patients with stable coronary artery disease

    Get PDF
    INTRODUCTION: Familial hypercholesterolemia (FH) is an inherited disorder characterized by elevated plasma levels of low-density lipoprotein cholesterol (LDL-C) associated with premature cardiovascular disease. METHODS: Using the data from the START (STable Coronary Artery Diseases RegisTry) study, a nationwide, prospective survey on patients with stable coronary artery disease (CAD), we described prevalence and lipid lowering strategies commonly employed in these patients. The study population was divided into "definite/probable FH," defined as a Dutch Lipid Clinic Network (DLCN) score ≥6, "possible FH" with DLCN 3-5, and "unlikely FH" in presence of a DLCN <3. RESULTS: Among the 4030 patients with the DLCN score available, 132 (3.3%) were classified as FH (2.3% with definite/probable and 1.0% with possible FH) and 3898 (96.7%) had unlikely FH. Patients with both definite/probable and possible FH were younger compared to patients not presenting FH. Mean on-treatment LDL-C levels were 107.8 ± 41.5, 84.4 ± 40.9, and 85.8 ± 32.3 (P < 0.0001) and a target of ≤70 mg/dL was reached in 10.9%, 30.0%, and 22.0% (P < 0.0001) of patents with definite/probable, possible FH, and unlikely FH, respectively. Statin therapy was prescribed in 85 (92.4%) patients with definite/probable FH, in 38 (95.0%) with possible FH, and in 3621 (92.9%) with unlikely FH (P = 0.86). The association of statin and ezetimibe, in absence of other lipid-lowering therapy, was more frequently used in patients with definite/probable FH compared to patients without FH (31.5% vs 17.5% vs 9.5%; P < 0.0001). CONCLUSIONS: In this large cohort of consecutive patients with stable CAD, FH was highly prevalent and generally undertreated with lipid lowering therapies

    ANMCO Scientific Statement: clinical management of hypercholesterolaemia in patients with acute coronary syndromes

    Get PDF
    LDL cholesterol (LDL-C) reduction after Acute Coronary Syndromes (ACS) is associated with a significant decrease in subsequent atherosclerotic cardiovascular events. Accordingly, international guidelines recommend a reduction of LDL-C below 70 mg/dL in ACS patients. Such a result can be effectively accomplished in most cases by using high intensity statins. In selected cases, the association with ezetimibe may be necessary in order to achieve recommended LDL-C targets. This document outlines management strategies that can be consistently implemented in clinical practice in order to achieve and maintain guidelines recommended therapeutic goals

    ANMCO Position Paper: diagnostic-therapeutic pathway in patients with hypercholesterolaemia and statin intolerance

    Get PDF
    Statins are a class of drugs used to lower total and low-density lipoprotein (LDL)-cholesterol. Clinical trials performed over the last 25 years have shown that these agents are effective in improving cardiovascular outcomes in several different clinical settings. However, in some cases statin treatment may be associated with significant side effects and adverse reactions. The occurrence of these adverse events during statin therapy may cause discontinuation of treatment, and hence the impossibility of achieving recommended lipid goals. The clinical condition in which patients experience major unacceptable symptoms and/or develop laboratory abnormalities during statin therapy is defined as statin intolerance. This document outlines the diagnostic and therapeutic pathways for the clinical management of patients with hypercholesterolaemia and statin intoleranc

    Induction of Colonic Aberrant Crypts in Mice by Feeding Apparent N-Nitroso Compounds Derived From Hot Dogs

    Get PDF
    Nitrite-preserved meats (e.g., hot dogs) may help cause colon cancer because they contain N-nitroso compounds. We tested whether purified hot-dog-derived total apparent N-nitroso compounds (ANC) could induce colonic aberrant crypts, which are putative precursors of colon cancer. We purified ANC precursors in hot dogs and nitrosated them to produce ANC. In preliminary tests, CF1 mice received 1 or 3 i.p. injections of 5mg azoxymethane (AOM)/kg. In Experiments 1 and 2, female A/J mice received ANC in diet. In Experiment 1, ANC dose initially dropped sharply because the ANC precursors had mostly decomposed but, later in Experiment 1 and throughout Experiment 2, ANC remained at 85 nmol/g diet. Mice were killed after 8 (AOM tests) or 17–34 (ANC tests) wk.Median numbers of aberrant crypts in the distal 2 cm of the colon for 1 and 3 AOMinjections, CF1 controls, ANC (Experiment 1), ANC (Experiment 2),and untreated A/J mice were 31, 74, 12, 20, 12, and 5–6, with P < 0.01 for both ANC tests. Experiment 2 showed somewhat increased numbers of colonic mucin-depleted foci in the ANC-treated group. We conclude that hot-dog-derived ANC induced significant numbers of aberrant crypts in the mouse colon

    Comparison between three different equations for the estimation of glomerular filtration rate in predicting mortality after coronary artery bypass

    Get PDF
    Background This study was undertaken to compare the accuracy of chronic kidney disease-epidemiology collaboration (eGFRCKD-EPI) to modification of diet in renal disease (eGFRMDRD) and the Cockcroft-Gault formulas of Creatinine clearance (CCG) equations in predicting post coronary artery bypass grafting (CABG) mortality. Methods Data from 4408 patients who underwent isolated CABG over a 11-year period were retrieved from one institutional database. Discriminatory power was assessed using the c-index and comparison between the scores’ performance was performed with DeLong, bootstrap, and Venkatraman methods. Calibration was evaluated with calibration curves and associated statistics. Results The discriminatory power was higher in eGFRCKD-EPI than eGFRMDRD and CCG (Area under Curve [AUC]:0.77, 0.55 and 0.52, respectively). Furthermore, eGFRCKD-EPI performed worse in patients with an eGFR ≤29 ml/min/1.73m2 (AUC: 0.53) while it was not influenced by higher eGFRs, age, and body size. In contrast, the MDRD equation was accurate only in women (calibration statistics p = 0.72), elderly patients (p = 0.53) and subjects with severe impairment of renal function (p = 0.06) whereas CCG was not significantly biased only in patients between 40 and 59 years (p = 0.6) and with eGFR 45–59 ml/min/1.73m2 (p = 0.32) or ≥ 60 ml/min/1.73m2 (p = 0.48). Conclusions In general, CKD-EPI gives the best prediction of death after CABG with unsatisfactory accuracy and calibration only in patients with severe kidney disease. In contrast, the CG and MDRD equations were inaccurate in a clinically significant proportion of patients

    Avoiding unnecessary ventricular pacing is associated with reduced incidence of heart failure hospitalizations and persistent atrial fibrillation in pacemaker patients

    Get PDF
    Aims In bradycardia patients treated with dual-chamber pacing, we aimed to evaluate whether pacing with atrioventricular (AV) delay management [AV hysteresis (AVH)], compared with standard pacing with fixed AV delays, reduces unnecessary ventricular pacing percentage (VPP) and is associated with better clinical outcomes. Main study endpoints were the incidence of heart failure hospitalizations (HFH), persistent atrial fibrillation (AF), and cardiac death. Methods Data from two identical prospective observational studies, BRADYCARE I in the USA and BRADYCARE II in Europe, Africa, and results and Asia, were pooled. Overall, 2592 patients (75 ± 10 years, 45.1% female, 50% with AVH) had complete clinical and device data at 1-year follow-up and were analysed. Primary pacing indication was sinus node disease (SND) in 1177 (45.4%), AV block (AVB) in 974 (37.6%), and other indications in 441 (17.0%) patients. Pacing with AVH, compared with standard pacing, was associated with a lower 1-year incidence of HFH [1.3% vs. 3.1%, relative risk reduction (RRR) 57.5%, P = 0.002] and of persistent AF (5.3% vs. 7.7%, RRR = 31.1%, P = 0.028). Cardiac mortality was not different between groups (1.0% vs. 1.4%, RRR = 27.8%, P = 0.366). Pacing with AVH, compared with standard pacing, was associated with a lower (P &lt; 0.001) median VPP in all patients (7% vs. 75%), in SND (3% vs. 44%), in AVB (25% vs. 98%), and in patients with other pacing indications (3% vs. 47%).Conclusion Cardiac pacing with AV delay management via AVH is associated with reduced 1-year incidence of HFH and persistent AF, most likely due to a reduction in VPP compared to standard pacing

    Evaluating the Effect of Chemical Digestion Treatments on Polystyrene Microplastics: Recommended Updates to Chemical Digestion Protocols

    Get PDF
    Establishing the toxicity and exposure consequences of microplastics (MPs) on marine organisms relies on the nondestructive isolation of plastics from biological matrices. MPs are commonly extracted from these matrices by chemical digestion using alkali (e.g., potassium hydroxide (KOH) and sodium hydroxide (NaOH)), oxidative (e.g., hydrogen peroxide (H2O2)) and/or acidic (e.g., nitric acid (HNO3)) reagents. Although these digestion conditions can be highly effective for MP extraction, they can also react with the plastics. This can attribute an inaccurate representation of plastic contamination by altering MP visual characteristics (size, shape, color), thereby impeding identification and potentially returning erroneous numbers of ingested particles. In this study, the degradative impacts are assessed of the routinely applied digestion reagents (i) KOH, (ii) NaOH, (iii) H2O2, and (iv)HNO3 on polystyrene (PS) based MPs sized between 200 ÎĽm and 5 mm. Degradation of the PS MPs is evaluated using FT-IR, gel permeation chromatography, NMR, photoluminescence spectroscopy, and microscopy. These studies reveal HNO3 to be the most destructive for PS MPs, while the alkali and oxidative reagents result in negligible changes in plastic properties. These results are recommended to be used as a guideline to update current protocols to ensure the nondestructive treatment of MPs
    • …
    corecore