Sneddon syndrome. Presentation of 2 cases

Sneddon syndrome is a systemic non inflammatory arteriopathy characterized by the association of livedo reticularis, thrombotic cerebrovascular disease, coronary artery disease and hypertension. Middle age females are usually affected. It should be considered in the differential diagnosis of acute ischemic attacks in younger patients. It has been related to the antiphospholipid antibody syndrome. Treatment is based on control of hypertension and cardiovascular risk factors along with antiplatelet agents. Two cases meeting the clinical criteria outlined above are reported.     

The Role of Glycosyltransferases in Colorectal Cancer

Colorectal cancer (CRC) is one of the main causes of cancer death in the world. Post-translational modifications (PTMs) have been extensively studied in malignancies due to its relevance in tumor pathogenesis and therapy. This review is focused on the dysregulation of glycosyltransferase expression in CRC and its impact in cell function and in several biological pathways associated with CRC pathogenesis, prognosis and therapeutic approaches. Glycan structures act as interface molecules between cells and their environment and in several cases facilitate molecule function. CRC tissue shows alterations in glycan structures decorating molecules, such as annexin-1, mucins, heat shock protein 90 (Hsp90), β1 integrin, carcinoembryonic antigen (CEA), epidermal growth factor receptor (EGFR), insulin-like growth factor-binding protein 3 (IGFBP3), transforming growth factor beta (TGF-β) receptors, Fas (CD95), PD-L1, decorin, sorbin and SH3 domain-containing protein 1 (SORBS1), CD147 and glycosphingolipids. All of these are described as key molecules in oncogenesis and metastasis. Therefore, glycosylation in CRC can affect cell migration, cell–cell adhesion, actin polymerization, mitosis, cell membrane repair, apoptosis, cell differentiation, stemness regulation, intestinal mucosal barrier integrity, immune system regulation, T cell polarization and gut microbiota composition; all such functions are associated with the prognosis and evolution of the disease. According to these findings, multiple strategies have been evaluated to alter oligosaccharide processing and to modify glycoconjugate structures in order to control CRC progression and prevent metastasis. Additionally, immunotherapy approaches have contemplated the use of neo-antigens, generated by altered glycosylation, as targets for tumor-specific T cells or engineered CAR (Chimeric antigen receptors) T cells.     

Removal properties of crosslinked poly(2‐acrylamido glycolic acid) for trace heavy metal ions: Effect of pH,temperature, contact time,and salinity on the adsorption behavior

Crosslinked poly(2‐acrylamido glycolic acid) resin was synthesized by radical polymerization. This resin contains three potential ligand groups and was studied as an adsorbent of trace heavy metal ions from a saline aqueous solution and sea water by using the Batch equilibrium procedure. Adsorption characteristics of the resin toward Cu(II), Ni(II), Cd(II), and Pb(II) were studied spectrophotometrically, both in competitive and noncompetitive conditions. The effect of pH, contact time, amount of sorbent, temperature, and salinity were studied. The resin showed a high affinity particularly for Ni(II). It was possible to remove completely Ni(II) and Pb(II) from the resin by 4M HNO₃. The retention properties of the resin were also investigated for Cu(II) contained in natural sea waters. The retention behavior was similar to that of the synthetic metal ion aqueous solution. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2614–2621, 2003     

Effect of chemically modified clinoptilolite on the thermal,morphological, and gas separation properties of mixed matrix membranes

Mixed matrix membranes (MMM) based on polysulfone and chemically modified clinoptilolite were prepared. Clinoptilolite enriched with Ca²⁺, K⁺, and Na⁺ by ion exchange at two test temperatures was prepared. Chemical composition was monitored by energy dispersive X‐ray spectroscopy. X‐ray diffraction, thermogravimetric analysis, and N₂ adsorption–desorption isotherms were also performed. Thermal and morphological properties of MMM were evaluated. CH₄/CO₂ gas mixture permeability tests at different upstream pressure were carried out. Type of exchanged cation in modified clinoptilolite affected the CO₂ permeability. An improvement on the CO₂/CH₄ selectivity values in the MMM compared to the polymeric membrane was appreciated. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45659.     

Automatic Control System for Thermal State of Reverberatory Furnaces in Production of Nickel Alloys

Metallurgist - The paper describes the development of an automated digital system for monitoring and controlling the thermal regime of gas reverberatory furnaces for fire refining of nickel based...     

Creep characterization of solder bumps using nanoindentation

Current nanoindentation techniques for the measurement of creep properties are applicable to viscoplastic materials with negligible elastic deformations. A new technique for characterization of creep behavior is needed for situations where the elastic deformation plays a significant role. In this paper, the effect of elastic deformation on the determination of creep parameters using nanoindentation with a self-similar nanoindenter tip is evaluated using finite element analysis (FEA). It is found that the creep exponent measured from nanoindentation without taking into account of the contribution of elastic deformation tends to be higher than the actual value. An effective correction method is developed to consider the elastic deformation in the calculation of creep parameters. FEA shows that this method provides accurate creep exponent. The creep parameters, namely the creep exponent and activation energy, were measured for three types of reflowed solder bumps using the nanoindentation method. The measured parameters were verified using FEA. The results show that the new correction approach allows extraction of creep parameters with precision from nanoindentation data.     

Study of propylene‐1‐butene‐ethylene terpolymer and reactor blend by TREF and 13C‐NMR

A terpolymer of propylene‐1‐butene‐ethylene (TERPO) and a reactor mixture of TERPO with an ethylene‐1‐butene copolymer (BLEND) were completely characterized by TREF, ¹³C‐NMR, DSC, and GPC, from which special equations for quantitative ¹³C‐NMR were derived. TERPO was shown to be composed mainly of highly isotactic propene and similar amounts of ethylene and 1‐butene. BLEND fractions were composed of variable amounts of TERPO and a random copolymer of ethylene‐1‐butene. The blend of TERPO and copolymer acts as two independent phases, each having its own elution temperatures dependent only on its crystallizability, itself only influenced by the comonomer content. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1880–1890, 2001     

Nanocluster Collisions as a Way to Understand the Role of d-Shell Polarization

Collision processes between single gold and rhodium atoms and gold and rhodium nanoclusters, respectively, are used to study the interplay between the large elastic energies and the much smaller magnetic interactions. The latter, in spite of their small magnitude, often settle the configuration of crystals, clusters, and molecules. We implement ab initio molecular dynamics (DFT-MD) calculations to investigate the subtle balance between these two forces. The targets we consider are minimum energy 13 (12) atom gold (rhodium) clusters. Results for gold and rhodium are compared emphasizing the relevance of d-shell polarization. The use of these collision processes to generate putative nanocluster minimum energy configurations will be presented and illustrated with successful examples.     

Stability of methylcellulose-based films after being subjected to different conservation and processing temperatures

Methylcellulose films with and without sorbitol addition were developed. The major objective of this study was to attempt insights into the stability of the methylcellulose-based film properties after having been subjected to freezing, storage or a combination of both procedures. The importance of the sorbitol concentration and process temperature was also to be elucidated. As-prepared film solubility decreased at 100 °C, as a result of the methylcellulose thermogelation property when the samples were exposed to high temperatures.By analyzing the film pattern behavior and its properties 0.25% w/v sorbitol concentration turned out to be an inflexion point. The moisture content as well as the mechanical and thermal properties made this fact evident. Moreover the elastic modulus (E_c) and glass transition temperature (T_g) did not undergo significant changes for higher plasticizer concentrations. The methylcellulose film properties remained more stable in the presence of sorbitol, which would act as a protective agent due to its hydrogen bonding capacity. This stability is crucial for film and coating applications in the food industry.