Diphenyl-Methane Based Thyromimetic Inhibitors for Transthyretin Amyloidosis

Thyromimetics, whose physicochemical characteristics are analog to thyroid hormones (THs) and their derivatives, are promising candidates as novel therapeutics for neurodegenerative and metabolic pathologies. In particular, sobetirome (GC-1), one of the initial halogen-free thyromimetics, and newly synthesized IS25 and TG68, with optimized ADME-Tox profile, have recently attracted attention owing to their superior therapeutic benefits, selectivity, and enhanced permeability. Here, we further explored the functional capabilities of these thyromimetics to inhibit transthyretin (TTR) amyloidosis. TTR is a homotetrameric transporter protein for THs, yet it is also responsible for severe amyloid fibril formation, which is facilitated by tetramer dissociation into non-native monomers. By combining nuclear magnetic resonance (NMR) spectroscopy, computational simulation, and biochemical assays, we found that GC-1 and newly designed diphenyl-methane-based thyromimetics, namely IS25 and TG68, are TTR stabilizers and efficient suppressors of TTR aggregation. Based on these observations, we propose the novel potential of thyromimetics as a multi-functional therapeutic molecule for TTR-related pathologies, including neurodegenerative diseases.     

Isolation of the effect of the hairy layer length on the mechanical properties of waterborne coatings

The effect of the acidic hairy layer length on the interdiffusion of polymer between particles and as a consequence on the mechanical properties of the films produced from waterborne coatings has been studied. In order to isolate this effect, latexes with the same particle diameter and molecular weight but stabilized with poly(acrylic acid)-block-poly(butyl acrylate) (PAA-b-PBA) block copolymers of controlled and different lengths were prepared. Tensile strength measurements showed at the macroscopic level that the presence of AA chains in the particle surface reduced the mechanical properties of the films dried at room temperature, being its effect worse the longer the AA chain length. Higher annealing temperatures erased the negative effect of the acidic hairy layer on mechanical properties. The neutralization with NaOH instead of with NH₄OH also led to worse mechanical properties. These macroscopic results were supported by Fluorescence Resonance Energy Transfer (FRET) experiments that showed that at the microscopic level, the extent of interdiffusion occurred slower when the AA chains in the particles surface increased, the annealing temperature was lower and when NaOH was used as neutralizing agent instead of NH₄OH.     

New developments in speciality polymers: polymeric stabilizers

Many new speciality polymers have been developed in the last few years. In this paper polymeric stabilizers (antioxidants, flame retardants and ultraviolet stabilizers) will be discussed. Polymeric antioxidants of the hindered-phenol type, copolymers of 2,6-ditertiarybutyl-4-vinyl(or isopropenyl)phenol with styrene, methyl methacrylate, or more importantly butadiene or isoprene have been prepared; hydrogenation of the latter copolymers gave copolymers of the two polymerizable phenolic antioxidants with ethylene or ethylene/propylene. The polymeric antioxidants have been blended with diene polymers and selected polyolefins and have improved the long-term oxidative stability of these polymers. Polymeric flame retardants have been prepared by copolymerizing styrene and/or acrylonitrile with acrylates and methacrylates of aliphatic bromine-containing alcohols or bromine-containing phenols. Polymers with polymer-bound flame retardants have a higher limiting oxygen index compared with the original polymer. A new class of polymerizable ultraviolet stabilizers has also been developed; these stabilizers are styryl, α-methylstyryl, acryloyl and methacryloyl derivatives of 2(2-hydroxyphenyl)2H-benzotriazoles. These monomers have been copolymerized with styrene, acrylates and methacrylates. 2(2-Hydroxyphenyl)2H-benzotriazoles substituted in the 4 position of the benzotriazole ring with hydroxyl, acetoxy or carboxyl groups suitable for incorporation into polyesters, polycarbonates, polyamides and epoxy resins have also been synthesized. All 2(2-hydroxyphenyl)2H-benzotriazole ultraviolet absorbers and the polymers into which they are incorporated have high light absorbency with γ_max between 330 and 350 nm and extinction coefficients in some cases as high as 4.5 × 10⁴ 1 mol^?1 cm^?1.     

Recrystallization in Model Ice Cream Solutions as Affected by Stabilizer Concentration

Ice recrystallization rates in simple aqueous solutions comprising fructose and a hydrocolloid stabilizer were measured. The stabilizers were an enzyme-modified guar and a non-gelling high methoxy pectin. The stabilizer concentration dependence of the recrystallization rates for both materials was similar in that increasing the concentration resulted in decreasing rates until a point is reached where further addition had no additional effect. That recrystallization rates were reduced by both gelling and non-gelling stabilizers was strongly suggestive that gelation was not a requirement for recrystallization inhibition and another more specific mechanism applies, for example a weak interfacial effect such as adsorption or blocking. This behavior was also seen with locust bean gum and guar and provided further empirical evidence to support the hypothesis that stabilizers adsorb to ice crystal surfaces.     

反应型聚合物稳定剂的研究进展

通用塑料在阳光作用下都会降解，添加稳定剂可成功地解决此问题。但是，在某些情况下普通的稳定剂不能满足这种要求，这就促进了新的反应型稳定剂的发展。低分子稳定剂的接枝可克服草取问题。研究反应型稳定剂是提高聚合物的耐热性和耐草取性的一种发展趋势。按反应性基团的不同，该类稳定剂可分为乙烯基型、丙烯酰基型和其他类型。文章综述了反应型稳定剂的合成和应用，还介绍了其中一些商业化的品种。     

国际以及国内土壤固化剂的研究现状和前景展望

将现有土壤固化剂分成四类，分析各类土壤固化剂的优缺点。总结现有的土壤固化机理．并对土壤固化剂的发展提出四点有意义的建议。     

Innovative Ingredients and Emerging Technologies for Controlling Ice Recrystallization,Texture, and Structure Stability in Frozen Dairy Desserts: A Review

Over the past decade, ice cream manufacturers have developed a strong understanding of the functionality of key ingredients and processing, developing effective explanations for the link between structure forming agents, stability mechanisms, and perceived quality. Increasing demand for products perceived as healthier/more natural with minimal processing has identified a number of new tools to improve quality and storage stability of frozen dairy desserts. Ingredients such as dietary fiber, polysaccharides, prebiotics, alternate sweeteners, fat sources rich in unsaturated fatty acids and ice strucsturing proteins (ISP) have been successfully applied as cryoprotective, texturizing, and structuring agents. Emerging minimal processing technologies including hydrostatic pressure processing, ultrasonic or high pressure assisted freezing, low temperature extrusion and enzymatically induced biopolymers crosslinking have been evaluated for their ability to improve colloidal stability, texture and sensory quality. It is therefore timely for a comprehensive review.     

关于泡沫混凝土稳泡剂的探讨

介绍了泡沫混凝土稳泡剂的概念、作用机理、种类,并且通过例举相关试验,讲解了混凝土稳泡剂的选择及使用方法,以推动泡沫混凝土稳泡剂的研究和发展,提高泡沫混凝土的性能。     

化学镀镍-磷合金复合稳定剂的优化研究

采用正交试验研究了稳定剂硫酸铜、碘酸钾、DL-半胱氨酸和硫酸铈复合使用对化学镀Ni-P合金镀液稳定性、镀速、镀层磷含量和孔隙率等性能的影响变化规律。结果表明,各种稳定剂之间有相互促进作用,综合性能明显优于单一稳定剂,且复合使用采用了清洁的原料,替代了重金属Pb2+;稳定剂硫酸铜、碘酸钾、DL-半胱氨酸和硫酸铈最佳复配的质量浓度分别为:25、20、3和7.5mg/L,镀后测得镀速12.54μm/h、镀液稳定常数91.85%、孔隙率0、镀层磷质量分数为10.25%。     

航空燃料高温裂解条件下热稳定添加剂的研究进展

介绍了供氢剂和结焦抑制剂两类热稳定剂抑制航空燃料高温（>400 ℃）热裂解期结焦的研究进展。评述了一元、二元供氢剂以及含磷、有机硒、含硫结焦抑制剂的抑焦机理及其抑焦效果,并提出今后的研究方向。