Multiple Chemical Features Impact Biological Performance Diversity of a Highly Active Natural Product-Inspired Library

A systematic, diversity-oriented synthesis approach was employed to access a natural product-inspired flavonoid library with diverse chemical features, including chemical properties, scaffold, stereochemistry, and appendages. Using Cell Painting, the effects of these diversity elements were evaluated, and multiple chemical features that predict biological performance diversity were identified. Scaffold identity appears to be the dominant predictor of performance diversity, but stereochemistry and appendages also contribute to a lesser degree. In addition, the diversity of chemical properties contributed to performance diversity, and the driving chemical property was dependent on the scaffold. These results highlight the importance of key chemical features that may inform the creation of small-molecule, performance-diverse libraries to improve the efficiency and success of high-throughput screening campaigns.     

Cachexia,a Systemic Disease beyond Muscle Atrophy

Cachexia is a complication of dismal prognosis, which often represents the last step of several chronic diseases. For this reason, the comprehension of the molecular drivers of such a condition is crucial for the development of management approaches. Importantly, cachexia is a syndrome affecting various organs, which often results in systemic complications. To date, the majority of the research on cachexia has been focused on skeletal muscle, muscle atrophy being a pivotal cause of weight loss and the major feature associated with the steep reduction in quality of life. Nevertheless, defining the impact of cachexia on other organs is essential to properly comprehend the complexity of such a condition and potentially develop novel therapeutic approaches.     

Water-repellent films from corn protein and tomato cutin

Flexible and hydrophobic biobased films were obtained using zein esterified with methanol and para-toluene (p-toluene) sulfonic acid, cutin from tomato peels and ethanol. Esterification was confirmed by proton nuclear magnetic resonance and attenuated total reflectance–Fourier transform infrared spectroscopy (ATR-FTIR). Non-modified zein films were brittle and hydrophilic. ATR-FTIR demonstrated that zein esterification increased zein hydrophobicity. Without cutin, esterified zein films were hydrophobic but brittle. Addition of cutin yielded films that were flexible and hydrophobic, as demonstrated by contact angle measurements. Principal component analysis (PCA) of ATR-FTIR data showed that intensities at 3195 cm⁻¹ and 3490 cm⁻¹ were correlated to the relative hydrophobicity of zein films. PCA also showed that films of esterified zein and cutin were more hydrophobic than their counterparts (non-modified zein without cutin). Optical and scanning electron microscopy demonstrated that esterified zein was compatible with cutin and yielded cohesive films, which did not fracture upon bending.     

A microfluidic approach for development of hybrid collagen-chitosan extracellular matrix-like membranes for on-chip cell cultures

To advance organ-on-a-chip development and other areas befitting from physiologically-relevant biomembranes,a microfluidic platform is presented for synthesis of biomembranes during gelation and investigation into their role as extracellular matrix supports.In this work,high-throughput studies of collagen,chitosan,and collagen-chitosan hybrid biomembranes were carried out to characterize and compare key properties as a function of the applied hydrodynamic conditions during gelation.Specifically,depending on the biopolymer material used,varying flow conditions during biomembrane gelation caused width,uniformity,and swelling ratio to be differently affected and controllable.Finally,cell viability studies of seeded fibroblasts were conducted,thus showing the potential for biological applications.     

Two-step route polycondensation for polynaphthalimides synthesis through high molar mass soluble precursors: A kinetic study

Research of polynaphthalimides (PNI) frequently reports difficulties over synthesis and processing due to insolubility. In this work, we present a novel comprehensive study on the effects of time, temperature and catalyst on the synthesis of soluble PNI precursors—polyamic acids (PAAs)—, as well as a novel synthetic procedure for the synthesis of PNI using mild conditions. Kinetic studies concerning the monomer conversion and the degree of premature imidization were performed through proton nuclear magnetic resonance and gel permeation chromatography for temperature ranging from 25 to 100°C. High temperatures (above 60°C) entail extensive premature imidization and insolubility. The use of triethylamine also catalyzes imidization. At the optimal condition, soluble PAA precursors for PNI of 72 kDa could be obtained at 40°C in N-methyl-2-pyrrolidone solution (30 wt%) after 5 hr polymerization.     

Effect of rheology and humic acids on the transport of environmental fluids: Potential implications for soil remediation revealed through microfluidics

This study investigated the potential effect of shear rheology and humic acids (HA) on the subsurface transport of polymeric fluids used for the remediation of contaminants. Polymeric fluids were prepared with guar, scleroglucan, and carboxymethyl cellulose (CMC). Guar fluids can be used to suspend reactive particles for contaminant degradation. Fluids prepared with 2.5 g/L of guar in water were viscous, and the crosslinker borax (1 g/L) made them viscoelastic. Microfluidics experiments showed that the increase in elasticity blocked the flow of guar in 350 μm channels. Guar, CMC, or scleroglucan fluids containing sodium thiosulfate can be used to trap toxic Cr(VI) in the subsurface and reduce it to harmless Cr(III). Trapping of Cr(VI) is achieved by the gelation of the fluids upon contact with chromium. Before mixing with chromium, HA did not affect the flow of CMC, guar, and scleroglucan in microfluidic channels. Quartz-crystal microbalance with dissipation monitoring experiments indicates that HA reduced sorption of guar onto silica, potentially promoting the transport of guar fluids in sandy aquifers. While HA slightly decreased the rate of gelation of CMC and scleroglucan upon contact with chromium, it did not affect the fast gelation rate of guar. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48465.     

Identification of vivianite,an unusual blue pigment,in a sixteenth century painting and its implications

Vivianite, a blue pigment employed in the past practically only in Northern and Central Europe, but with very limited use, was identified in an early sixteenth century painting, stylistically with Flemish features, from a church in Portugal. The identification of this iron phosphate mineral was made by SEM‐EDS based on the atomic ratio between phosphorus and iron in layers of blue paint (area analysis) and in particles of these same layers (spot analysis). This painting, about which there is no document to prove its authorship, becomes the first case, known in detail, of a sixteenth century painting containing vivianite. Moreover, this find and the presence of a chalk ground, also identified, strongly support the hypothesis of being a Flemish painting.     

Piperazine and methyldiethanolamine interrelationships in CO2 absorption by aqueous amine mixtures. Part II—Saturation rates of mixed reagent solutions

This work is a companion to a previous article, Part I, published in The Canadian Journal of Chemical Engineering, dealing with CO₂ absorption in aqueous solutions containing a single aminic reagent (specifically methyldiethanolamine (MDEA) or piperazine (PZ)). In this second part, different PZ/MDEA mixtures are experimentally studied and their performances are compared with that of the single reagents. It is indeed well known that small quantities of PZ added to MDEA aqueous solutions are sufficient to obtain a significant improvement in the kinetics of the process. PZ is considered an activator or promoter for MDEA, but the mechanism of this synergy has still not been clearly demonstrated. The aim of this study is an attempt to understand how PZ and MDEA can interact by experimentally analyzing this beneficial mutual effect and by explaining it with the help of a suitable yet not complex model. We believe that the involved chemistry is not more complex than that reported in Part I for the single reagents. According to our findings, it is MDEA that enhances the action of PZ, as opposed to what many authors claim. Moreover, our results seem to rule out the existence of any PZ shuttle effect.