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The recovery of metals from tailing ponds or dumps is a priority as they remained stored on large areas around the mining operations and represent an aggressive pollution source of natural water bodies. The paper objective is to develop a combined process for iron-containing mine tailings capitalization associates the benefits of magnetic separation to reduce the iron content, microwave digestion for metals forms solubilization from solid matrix and microemulsion for their extraction, concentration, and recycling from the digested sample. The magnetic separation of ferromagnetic fraction, with over 50 % iron, leads to an improved extraction efficiency. The optimum digestion procedure uses aqua regia, hydrogen peroxide (30 % H 2 O 2) and microwaves. The microemulsion extraction using Brij 30 (polyoxyethylene (4) lauryl ether) as surfactant, ethyl acetate:butyl acetate (1:1, v/v) as oil phase and acidic metal solutions as aqueous phase, and also NaSCN (0.1 M) as carrier agent, performed at room temperature and atmospheric pressure, reveals that excellent recovery performance for iron (98.3 %), lead (98.5 %), zinc (93.0 %) can be obtained. In addition, copper (63.0 %) is recovered quite efficiently. The maximum microemulsion loading capacity in terms of mass of total metal ions/L was 351 mg/L and was achieved by two successive extractions. It has been demonstrated that by two successive extractions, the loading capacity is mainly represented by iron content. The results obtained demonstrate that the three combined procedures involving magnetic separation, microwave digestion and microemulsion assisted extraction ccontributes to the reduction of mine waste deposits and, consequently, the environmental pollution with heavy metals. [ABSTRACT FROM AUTHOR]

Aims - Baseline mechanical intraventricular dyssynchrony showed only a weak correlation with response to CRT in HF patients with wide QRS. We aimed to evaluate the effects of RV pacing on baseline intraventricular dyssynchrony in patients submitted to CRT. Methods - In 40 consecutive HF patients (LBBB, sinus rhythm, normal PR interval, 22 ischemic etiology, 65.5±10.7 years, 21 women, NYHA class 3.3 ± 0.5, LV ejection fraction 20.1±4.1%), speckle tracking radial strain was performed during sinus rhythm (ODO mode) and during RV pacing (DDD with optimum AV interval) one week after biventricular device implantation. RV lead was placed on interventricular septum (RVS, n=30) and RV apex (RVA, n=10). Patients had significant baseline intraventricular dyssynchrony, (i.e. =130 ms time difference in peak septal wall to infero-lateral wall strain). Maximum LV delay area (MDA) was defined as the segment with the latest systolic peak from the 6 regional color-coded time-strain curves. Midventricular global radial strain (mGRS) was determined averaging the segmental radial strain values. Results - Overall, RV pacing did not significantly increased intraventricular dyssynchrony (350±98 ms vs. 322±90 ms during SR, p=0.08). However, RVA pacing significantly increased LV dyssynchrony (367±58 ms vs. 312±60 ms during SR, p<0.001). mGRS was significantly reduced during RV pacing (13.3±8.5% vs. 18.3±7.4% during SR, p<0.001). The location of MDA shifted during RV pacing in 31 out of 40 patients (77%). Conclusions - In HF patients with wide QRS submitted to CRT, RV pacing alters the pattern of intraventricular dyssynchrony and impairs LV strain. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Proinflammatory cytokines, matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) play a role in left ventricular (LV) structural remodeling. We aimed to investigate the effects of cardiac resynchronization therapy (CRT) on serum levels of amino-terminal prohormone B-type natriuretic peptide (NT-proBNP), some interleukins (IL-1β, IL-6, IL-8), MMP-2 and TIMP-2 in patients with chronic heart failure (CHF). Design and methods: We studied 27 patients (15 M/12 F) with CHF, III–IV NYHA class, implanted with a biventricular pacemaker/defibrillator and 40 healthy subjects (23 M/17 F). Blood samples were collected at baseline and 1week, 3, 6, and 12months after CRT device implantation. Cardiac function was assessed echocardiographically. Results: CRT induced significant improvement in the NYHA class (baseline 3.2±0.5 vs. 1.0 at 12months, P=0.0002) and significant LV reverse remodeling, with a 41% (P=0.001) reduction in LV end-systolic volume (LVESV). This was associated with a significant reduction in serum NT-proBNP, IL-6 and IL-8. Positive extracellular matrix remodeling was illustrated by decreasing levels of MMP-2 and increasing TIMP-2. MMP-2/TIMP-2 ratio decreased with 55% (P=0.003) from baseline value at 12months and the correlation with LVESV reduction was 0.41 (P=0.001). Conclusions: Structural response to CRT is associated with reduced immune activation and positive extracellular matrix remodeling. [Copyright &y& Elsevier]

Summary: Protein-RNA interactions are fundamental to core biological processes, such as mRNA splicing, localization, degradation, and translation. We developed a photoreactive nucleotide-enhanced UV crosslinking and oligo(dT) purification approach to identify the mRNA-bound proteome using quantitative proteomics and to display the protein occupancy on mRNA transcripts by next-generation sequencing. Application to a human embryonic kidney cell line identified close to 800 proteins. To our knowledge, nearly one-third were not previously annotated as RNA binding, and about 15% were not predictable by computational methods to interact with RNA. Protein occupancy profiling provides a transcriptome-wide catalog of potential cis-regulatory regions on mammalian mRNAs and showed that large stretches in 3′ UTRs can be contacted by the mRNA-bound proteome, with numerous putative binding sites in regions harboring disease-associated nucleotide polymorphisms. Our observations indicate the presence of a large number of mRNA binders with diverse molecular functions participating in combinatorial posttranscriptional gene-expression networks. [ABSTRACT FROM AUTHOR]