Search results for "stabilizer."

Studio dell'interazione di DNA con complessi di metalli di transizione

2014

Biopolyester-based systems containing naturally occurring compounds with enhanced thermooxidative stability

2016

Background This work presents a sustainable approach for the stabilization of polylactic acid (PLA) against thermo-oxidative aging. Methods Naturally occurring phenolic and polyphenolic compounds, such as ferulic acid (FerAc), vanillic acid (VanAc), quercetin (Querc) and vitamin E (VitE), were introduced into PLA. Results The preliminary characterization of the systems formulated containing different amounts of natural stabilizers showed that all compounds used acted as plasticizers, leading to a decrease in rheological functions with respect to neat PLA, without significantly modifying the crystallinity of the raw material. The study of the thermo-oxidative behavior of neat PLA and PLA/nat…

Analytical tools used for the identification and quantification of pectin extracted from plant food matrices, wastes and by-products: A review

2018

Pectin is the methylated ester of polygalacturonic acid and has a wide range of applications. It can be used in food and animal feed as well as in pharmaceutical and cosmetic products. Pectin is traditionally used as a gelling agent in fruit-based products, as a stabilizer in some fruit juices and milk drinks and fruit filling for bakery and confectionary products, but their potential applications differ according to their chemical composition. Therefore, at this stage of development, it is of a great importance to find fast, reliable methods to not only identify and quantify pectin, but also to determine its chemical structure and composition when it is extracted from plant matrices, waste…

Efficacy of quetiapine XR vs. placebo as concomitant treatment to mood stabilizers in the control of subthreshold symptoms of bipolar disorder: Resul…

2017

Patients with bipolar disorder (BD) do not always achieve full remission between episodes. Subthreshold symptoms (depressive, manic or mixed) represent a major cause of relapse and disability in these patients. Immediate release (IR) and extended release (XR) formulations of quetiapine are both indicated for short and long-term treatment of BD. The aim of this study was to evaluate the efficacy of quetiapine XR vs placebo in subthreshold symptomatology when added to previous mood stabilizer treatment. A pilot phase IIIB, multicentre, prospective, placebo controlled, randomized, double blinded study of 12 weeks follow-up was performed (NCT01197846). Patients were randomized to quetiapine XR …

N-Valproyl-L-Phenylalanine as new potential antiepileptic drug: Synthesis, characterization and in vitro studies on stability, toxicity and anticonvu…

2013

Valproic acid (VPA) is considered first-line drug in treatment of generalized idiopathic seizures such as absence, generalized tonic-clonic and myoclonic seizures. Among major antiepileptic drugs, VPA is also considered effective in childhood epilepsies and infantile spasms. Due to its broad activity, VPA acts as a mood stabilizer in bipolar disorder and it is useful in migraine prophylaxis. Despite its long-standing usage, severe reactions to VPA, such as liver toxicity and teratogenicity, are reported. To circumvent side effects due to structural characteristics of VPA, we synthesized in good yield a new VPA-aminoacid conjugate, the N-valproyl-L-Phenylalanine, and characterized by FT-IR, …

Blood metal levels after minimally invasive repair of pectus excavatum

2021

Abstract   OBJECTIVES Minimally invasive repair of pectus excavatum (MIRPE) is the most popular surgical approach for paediatric patients with pectus excavatum. A substernal stainless still bar is inserted and left in place for 3 years and then removed. Our goal was to investigate blood metal levels after MIRPE and to correlate them with surgical details, such as the numbers of bars and stabilizers and the length of time the bar was in place. METHODS Blood levels of iron, chromium, manganese, molybdenum and nickel were analysed in 130 teenagers (108 boys and 22 girls) who had MIRPE using inductively coupled plasma mass spectrometry. A total of 62 patients were operated on using MIRPE (study…

Contributions of ACE and mast cell chymase to endogenous angiotensin II generation and leucocyte recruitment in vivo

2011

Aims In vitro studies suggest that mast cell chymase (MCP) is more important than angiotensin-converting enzyme (ACE) for generating angiotensin II (Ang II) within the cardiovascular system. We investigated in vivo the relative contributions of ACE and MCP to leucocyte recruitment induced by endogenously generated Ang II. Methods and results Exposure of the murine cremasteric microcirculation of C57BL/6 mice to Ang I (100 nM for 4 h) induced leucocyte–endothelium interactions. Either losartan (an Ang II receptor-1 antagonist, AT1) or enalapril (an ACE inhibitor), but not chymostatin (a chymase inhibitor), inhibited Ang I-induced responses. Mast cell degranulation with compound 48/80 (CMP48/…

Concentration-dependent anti-/pro-oxidant activity of natural phenolic compounds in bio-polyesters

2017

Abstract In this work, the potential of several naturally occurring phenolic compounds, such as Ferulic Acid (FA), Vanillic Acid (VA), Vitamin E (VE) and Quercetin (Q), as stabilizers against the photo-oxidative degradation of Polylactic acid (PLA) has been assessed. Specifically, PLA-based films containing different amounts of considered stabilizers have been formulated and their photo-stability under UVB exposure has been evaluated. The preliminary characterization of the formulated films shows that all used stabilizers exert plasticizing action, as probed by rheological analysis, due to their low molecular weight. Moreover, no significant modification of the PLA crystallinity has been no…

Photocatalytic degradation enhancement in pickering emulsions stabilized by solid particles of bare TiO 2

2019

Pickering emulsions provide a new way to enhance the efficiency of photocatalytic degradation of water-insoluble pollutants. Indeed, the semiconductor solid particles dually act as the photocatalyst and stabilizer of the emulsion droplets whose size dramatically affects the photocatalytic reaction. The present work aims at the validation of this concept by using bare TiO 2 without any surface modification. Nanostructured TiO 2 has been prepared by a simple sol-gel process and characterized by X-ray diffraction, specific surface area analysis, scanning electron microscopy, and diffuse reflectance spectroscopy. The emulsions were prepared by using 1-methylnaphthalene (1-MN) as a model organic…

Analysis of stability of food emulsions by Eyring's Theory: Influence of different biopolymers

2004

Eyring's kinetic theory of liquids was applied to the study of flow behavior of low oil content mayonnaises at different temperatures. These food emulsions were formulated with different biopolymers as stabilizers (polysaccharides such as modified starch, gellan gum, and pectin). The analysis of the values obtained for the parameters of the Eyring equation for viscosity determined the emulsion containing only starch as a stabilizer is the most unstable to stirring. Replacement of part of the starch with gellan gum or pectin enhances the stability of the emulsion. The results for activation energy are quite similar for high shear rates, which can be explained by the evolution of the average …