Tracking Hydroplasticization by DSC: Movement of Water Domains Bound to Poly(Meth)Acrylates during Latex Film Formation

The film formation step of latexes constitutes one of the challenges of these environmentally friendly waterborne polymers, as the high glass transition (TG) polymers needed to produce hard films to be used as coatings will not produce coherent films at low temperature. This issue has been dealt by the use of temporary plasticizers added with the objective to reduce the TG of the polymers during film formation, while being released to the atmosphere afterwards. The main problem of these temporary plasticizers is their volatile organic nature, which is not recommended for the environment. Therefore, different strategies have been proposed to overcome their massive use. One of them is the use of hydroplasticization, as water, abundant in latexes, can effectively act as plasticizer for certain types of polymers. In this work, the effect of three different grafted hydroplasticizers has been checked in a (meth)acrylate copolymer, concluding that itaconic acid showed the best performance as seen by its low minimum film-formation temperature, just slightly modified water resistance and better mechanical properties of the films containing itaconic acid. Furthermore, film formation monitoring has been carried out by Differential Scanning Calorimety (DSC), showing that itaconic acid is able to retain more strongly the water molecules during the water losing process, improving its hydroplasticization capacity.This research was funded by the Industrial Liaison Program of POLYMAT and by the Basque Government “Grupos Consolidados del Sistema Universitario Vasco”, grant number IT999-16

Full-wave EMC Simulations Using Maxwell Garnett Model For Composites With Cylindrical Inclusions

Four different models for effective dielectric properties of biphasic composite containing random or aligned cylindrical inclusions are considered in this paper. These models are based on the Maxwell Garnett (MG) mixing rule. The effects of distribution and orientation of cylindrical inclusions in a composite material is studied. An equivalent averaged material with Debye-like frequency characteristics, suitable for time-domain full-wave numerical electromagnetic simulations is retrieved. This Debye model is derived from the Maxwell Garnett formulation. The numerical model test structure consists of a composite slab inserted in a rectangular waveguide. Simulations are run for the frequency range above the cut-off frequency of the fundamental mode TE10. The differences between the proposed models are quantified using the Feature Selection Validation (FSV) tool. The comparison of the models provides an insight on the effect of inclusion orientation and distribution. © 2011 IEEE

Producción de látex híbridos acrílicos/alquídicos

In this work, the production of high solids content hybrid acrylic/alkyd latexes by miniemulsion polymerization is discussed. First, the miniemulsification procedure to achieve colloidally stable hybrid nanodroplets is presented. Next, the efficient nucleation of most nanodroplets during the polymerization, avoiding other nucleation mechanisms is presented. Finally, the key aspects to control the polymer architecture as well as the particle morphology are analyzed.Fil: Goikoetxea, Monika. Universidad del País Vasco; EspañaFil: Minari, Roque Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Beristain, Itxaso. Universidad del País Vasco; EspañaFil: Paulis, María. Universidad del País Vasco; EspañaFil: Asua, José M.. Universidad del País Vasco; EspañaFil: Barandiaran, María J.. Universidad del País Vasco; Españ

Suppression of β1-adrenoceptor autoantibodies is involved in the antiarrhythmic effects of omega-3 fatty acids in male and female hypertensive rats

The arrhythmogenic potential of β1-adrenoceptor autoantibodies (β1-AA), as well as antiarrhythmic properties of omega-3 in heart diseases, have been reported while underlying mechanisms are poorly understood. We aimed to test our hypothesis that omega-3 (eicosapentaenoic acid-EPA, docosahexaenoic acid-DHA) may inhibit matrix metalloproteinase (MMP-2) activity to prevent cleavage of β1-AR and formation of β1-AA resulting in attenuation of pro-arrhythmic connexin-43 (Cx43) and protein kinase C (PKC) signaling in the diseased heart. We have demonstrated that the appearance and increase of β1-AA in blood serum of male and female 12-month-old spontaneously hypertensive rats (SHR) was associated with an increase of inducible ventricular fibrillation (VF) comparing to normotensive controls. In contrast, supplementation of hypertensive rats with omega-3 for two months suppressed β1-AA levels and reduced incidence of VF. Suppression of β1-AA was accompanied by a decrease of elevated myocardial MMP-2 activity, preservation of cardiac cell membrane integrity and Cx43 topology. Moreover, omega-3 abrogated decline in expression of total Cx43 as well as its phosphorylated forms at serine 368 along with PKC-ε, while decreased pro-fibrotic PKC-δ levels in hypertensive rat heart regardless the sex. The implication of MMP-2 in the action of omega-3 was also demonstrated in cultured cardiomyocytes in which desensitization of β1-AR due to permanent activation of β1-AR with isoproterenol was prevented by MMP-2 inhibitor or EPA. Collectively, these data support the notion that omega-3 via suppression of β1-AA mechanistically controlled by MMP-2 may attenuate abnormal of Cx43 and PKC signaling; thus, abolish arrhythmia substrate and protect rats with an advanced stage of hypertension from malignant arrhythmias

Spontaneous Pneumo-Mediastinum in a Post-COVID-19 Patient with Systemic Sclerosis

Pulmonary involvement is the most common cause of death among patients with systemic sclerosis (SSc). The current coronavirus disease 2019 (COVID-19) is particularly problematic to manage in SSc patients since they may experience a more severe evolution of COVID-19 due to the pre-existent interstitial lung disease (ILD) and the administration of immunosuppressive treatments. In addition, the remarkable radiological similarities between SSc-ILD and COVID-19 complicate the differential diagnosis between these two entities. Herein, we present the first case of spontaneous pneumo-mediastinum in a post-COVID-19 patient with SSc. In our patient, both smoking and pulmonary fibrosis could lead to cyst formation, which possibly spontaneously broke and caused pneumo-mediastinum. Moreover, megaesophagus perforation due to the smooth muscle atrophy, replacement with fibrosis, and achalasia may extend into the mediastinum or pleural space and has also been described as a rare case of spontaneous pneumo-pericardium. Finally, spontaneous pneumo-mediastinum and pneumothorax have been recently reported as an established complication of severe COVID-19 pneumonia and among COVID-19 long-term complication. This case report underlines that the worsening of respiratory symptoms in SSc patients, especially when recovered from COVID-19, requires further investigations for ruling out other tentative diagnoses besides the evolution of the SSc-ILD

Ebola virus disease: In vivo protection provided by the PAMP restricted TLR3 agonist rintatolimod and its mechanism of action

Ebola virus (EBOV) is a highly infectious and lethal pathogen responsible for sporadic self-limiting clusters of Ebola virus disease (EVD) in Central Africa capable of reaching epidemic status. 100% protection from lethal EBOV-Zaire in Balb/c mice was achieved by rintatolimod (Ampligen) at the well tolerated human clinical dose of 6 mg/kg. The data indicate that the mechanism of action is rintatolimod's dual ability to act as both a competitive decoy for the IID domain of VP35 blocking viral dsRNA sequestration and as a pathogen-associated molecular pattern (PAMP) restricted agonist for direct TLR3 activation but lacking RIG-1-like cytosolic helicase agonist properties. These data show promise for rintatolimod as a prophylactic therapy against human Ebola outbreaks

No differences in physical activity between children with overweight and children of normal-weight

BACKGROUND: The aim of this study was to investigate the differences in objectively measured physical activity and in self-reported physical activity between overweight and normal-weight children. METHODS: Data from a prospective cohort study including children, presenting at the participating general practices in the south-west of the Netherlands, were used. Children (aged 4-15 years) were categorized as normal-weight or overweight using age- and sex specific cut-off points. They wore an ActiGraph accelerometer for one week to register physical activity, and filled out a diary for one week about physical activity. RESULTS: A total of 57 children were included in this study. Overweight children spent significantly less percentage time per day in sedentary behavior (β - 1.68 (95%CI -3.129, - 0.07)). There were no significant differences in percentage time per day spent in moderate to vigorous physical activity (β 0.33 (- 0.11, 0.78)). No significant differences were found between children of normal-weight and overweight in self-reported measures of physical activity. CONCLUSIONS: Overweight children are not less physically active than normal-weight children, which may be associated with the risen awareness towards overweight/obesity and with implemented interventions for children with overweight/obesity

The immune landscape of thyroid cancer in the context of immune checkpoint inhibition

Immune cells play critical roles in tumor prevention as well as initiation and progression. However, immune-resistant cancer cells can evade the immune system and proceed to form tumors. The normal microenvironment (immune cells, fibroblasts, blood and lymphatic vessels, and interstitial extracellular matrix (ECM)) maintains tissue homeostasis and prevents tumor initiation. Inflammatory mediators, reactive oxygen species, cytokines, and chemokines from an altered microenvironment promote tumor growth. During the last decade, thyroid cancer, the most frequent cancer of the endocrine system, has emerged as the fifth most incident cancer in the United States (USA), and its incidence is steadily growing. Inflammation has long been associated with thyroid cancer, raising critical questions about the role of immune cells in its pathogenesis. A plethora of immune cells and their mediators are present in the thyroid cancer ecosystem. Monoclonal antibodies (mAbs) targeting immune checkpoints, such as mAbs anti-cytotoxic T lymphocyte antigen 4 (anti-CTLA-4) and anti-programmed cell death protein-1/programmed cell death ligand-1 (anti-PD-1/PD-L1), have revolutionized the treatment of many malignancies, but they induce thyroid dysfunction in up to 10% of patients, presumably by enhancing autoimmunity. Combination strategies involving immune checkpoint inhibitors (ICIs) with tyrosine kinase (TK) or serine/threonine protein kinase B-raf (BRAF) inhibitors are showing considerable promise in the treatment of advanced thyroid cancer. This review illustrates how different immune cells contribute to thyroid cancer development and the rationale for the antitumor effects of ICIs in combination with BRAF/TK inhibitors