Recovery and concentration by electrodialysis of tartaric acid from fruit juice industries waste waters

Electrodialysis (ED) has been used as a membrane technique to concentrate tartaric acid from ion exchange regeneration waters obtained in grape juice treatment. The initial ion tartrate concentration in these streams varies between 1 and 10 kg m⁻³ and can be concentrated more than 60% (53·2 kg m⁻³ after 13300 s). Permeate flux of other common ionic components has been shown. Optimum intensities and current efficiency have been calculated with synthetic solutions. A mathematical approach has been used to predict final tartaric acid concentration and electro-osmotic effects. ©1997 SCI     

Redefining the Role of ADAM17 in Renal Proximal Tubular Cells and Its Implications in an Obese Mouse Model of Pre-Diabetes

Acute and chronic kidney lesions induce an increase in A Disintegrin And Metalloproteinase domain 17 (ADAM17) that cleaves several transmembrane proteins related to inflammatory and fibrotic pathways. Our group has demonstrated that renal ADAM17 is upregulated in diabetic mice and its inhibition decreases renal inflammation and fibrosis. The purpose of the present study was to analyze how Adam17 deletion in proximal tubules affects different renal structures in an obese mice model. Tubular Adam17 knockout male mice and their controls were fed a high-fat diet (HFD) for 22 weeks. Glucose tolerance, urinary albumin-to-creatinine ratio, renal histology, and pro-inflammatory and pro-fibrotic markers were evaluated. Results showed that wild-type mice fed an HFD became obese with glucose intolerance and renal histological alterations mimicking a pre-diabetic condition; consequently, greater glomerular size and mesangial expansion were observed. Adam17 tubular deletion improved glucose tolerance and protected animals against glomerular injury and prevented podocyte loss in HFD mice. In addition, HFD mice showed more glomerular macrophages and collagen accumulation, which was prevented by Adam17 deletion. Galectin-3 expression increased in the proximal tubules and glomeruli of HFD mice and ameliorated with Adam17 deletion. In conclusion, Adam17 in proximal tubules influences glucose tolerance and participates in the kidney injury in an obese pre-diabetic murine model. The role of ADAM17 in the tubule impacts on glomerular inflammation and fibrosis.     

Inhibition of PKCθ Improves Dystrophic Heart Phenotype and Function in a Novel Model of DMD Cardiomyopathy

Chronic cardiac muscle inflammation and subsequent fibrotic tissue deposition are key features in Duchenne Muscular Dystrophy (DMD). The treatment of choice for delaying DMD progression both in skeletal and cardiac muscle are corticosteroids, supporting the notion that chronic inflammation in the heart plays a pivotal role in fibrosis deposition and subsequent cardiac dysfunction. Nevertheless, considering the adverse effects associated with long-term corticosteroid treatments, there is a need for novel anti-inflammatory therapies. In this study, we used our recently described exercised mdx (ex mdx) mouse model characterised by accelerated heart pathology, and the specific PKCθ inhibitor Compound 20 (C20), to show that inhibition of this kinase leads to a significant reduction in the number of immune cells infiltrating the heart, as well as necrosis and fibrosis. Functionally, C20 treatment also prevented the reduction in left ventricle fractional shortening, which was typically observed in the vehicle-treated ex mdx mice. Based on these findings, we propose that PKCθ pharmacological inhibition could be an attractive therapeutic approach to treating dystrophic cardiomyopathy     

Membrane fractionation of a β-lactoglobulin tryptic digest: Effect of the pH

The tryptic digestion of β-lactoglobulin leads to the release of a large range of biologically active peptides. Ultrafiltration/nanofiltration technology can be used to fractionate protein hydrolysates in order to obtain permeate products with increased functionality and free from intact proteins and enzymes. The influence of the pH in the fractionation of the hydrolysate through a polyethersulfone membrane (MWCO 5 kDa) was investigated in this work. In this case peptide transmission was mainly governed by charge mechanisms and reached its maximum value when the pH value is close to the peptide isoelectric point. Almost complete rejection of acidic peptides was achieved at basic pH values due to electrostatic repulsive forces with the negatively charged membrane and, in agreement with Donnan theory, positively charged peptides shown lower transmission than the neutral species. The highest peptide recovery and the best separation factor between bioactive and non-bioactive peptides were obtained following nanofiltration at pH 8.0.     

Complex pBAE Nanoparticle Cell Trafficking: Tracking Both Position and Composition Using Super Resolution Microscopy

Nanomedicine emerged some decades ago with the hope to be the solution for most unmet medical needs. However, tracking materials at nanoscale is challenging to their reduced size, below the resolution limit of most conventional techniques. In this context, we propose the use of direct stochastic optical reconstruction microscopy (dSTORM) to study time stability and cell trafficking after transfection of oligopeptide end-modified poly(β-aminoester) (OM-pBAE) nanoparticles. We selected different combinations of cationic end oligopeptides (arginine – R; histidine – H; and lysine – K) among polymer libraries, since the oligopeptide combination demonstrated to be useful for different applications, such as vaccination and gene silencing. We demonstrate that their time evolution as well as their cell uptake and trafficking are dependent on the oligopeptide. This study opens the pave to broad mechanistic studies at nanoscale that could enable a rational selection of specific pBAE nanoparticles composition after determining their stability and cell trafficking.