Thermodynamic properties of cotton dyeing with indigo dyes in non-aqueous media of liquid paraffin and D5

On the basis of investigation into the dyeing equilibrium of cotton fibers with indigo dyes in decamethylcyclopentasiloxane (D5), liquid paraffin and water, the thermodynamic properties of cotton dyeing with indigo dyes in non-aqueous medium systems were studied in comparison with aqueous dyeing. The main works involved are as follows: firstly, the adsorption isotherms were created; then, the three theoretical adsorption models of Nernst, Langmuir and Freundlich were used to fit the adsorption isotherms created; finally, the thermodynamic parameters were calculated. The results showed that the adsorption isotherms were all in line with the Freundlich model. The order of dyeing affinity was in the sequence: liquid paraffin > D5 > water. The dyeing entropy in the three media showed positive values, which is mainly attributed to the adsorption of both indigo-leuco and water onto cotton fibers, thus reducing the ice-like structure formed among the water molecules in the dyeing system and the hydrophobic bonding structure formed among the non-aqueous medium molecules, then leading to an increase in the system disorder. The dyeing heat in the three media also showed positive values, due mainly to the absorption of thermal energy to “melt” the ice-like structure and to “break” the hydrophobic bonding structure. These dyeing thermodynamic properties are conducive to understanding and interpreting the dyeing performance and behavior of indigo dyes in non-aqueous dyeing systems.

Molecular Dynamics Mechanisms of the Inhibitory Effects of Abemaciclib, Hymenialdisine, and Indirubin on CDK-6

Background: Cyclin-Dependent Kinases-6 (CDK-6) is a serine/threonine protein kinase with regular activity in the cell cycle. Some inhibitors, such as abemaciclib, hymenialdisine, and indirubin, cause cell arrest by decreasing its activity. Objective: The purpose of this study was to evaluate the Molecular Dynamic (MD) effects of abemaciclib, hymenialdisine, and indirubin on the structure of CDK-6. Methods: The PDB file of CDK-6 was obtained from the Protein Data Bank (http://www.rcsb.org). After the simulation of CDK-6 in the Gromacs software, 200 stages of molecular docking were run on CDK-6 in the presence of the inhibitors using AutoDock 4.2. The simulation of CDK-6 in the presence of inhibitors was performed after docking. Results: Abemaciclib showed the greatest tendency to bind CDK-6 via binding 16 residues in the binding site with hydrogen bonds and hydrophobic bonding. CDK-6 docked to hymenialdisine and indirubin increased the Total Energy (TE) and decreased the radius of gyration (Rg). CDK-6 docked to hymenialdisine significantly decreased the coil secondary structure. Conclusion: CDK-6 is inhibited via high binding affinity to abemaciclib, hymenialdisine, and indirubin inhibitors and induces variation in the secondary structure and Rg in the CDK-6 docked to the three inhibitors. It seems that developing a drug with a binding tendency to CDK6 that is similar to those of abemaciclib, indirubin, and hymenialdisine can change the secondary structure of CDK6, possibly more potently, and can be used to develop anticancer drugs. However, additional studies are needed to confirm this argument.

Bonding BisGMA to Dentin—a Proof of Concept for Hydrophobic Dentin Bonding

The use of TEGDMA as a diluent comonomer in the formulation of hydrophobic adhesives for ethanol wet-bonding is a concern, due to its leaching potential, higher water sorption, and bio-incompatibility. This study tested the hypothesis that hydrophobic bonding to acid-etched dentin may be accomplished with the use of ethanol-solvated BisGMA only. Phosphoric-acid-etched, oxalate-occluded, deep coronal dentin bonded under 20 cm water pressure with experimental BisGMA adhesives by ethanol wet-bonding exhibited tensile strengths that were not significantly different from that achieved with OptiBond FL bonded according to the manufacturer-recommended protocol, with similar acid-/base-resistant hybrid layers, resin tags, and nanoleakage distribution. Ethanol replacement of water-saturated dentin produced wider interfibrillar spaces, more extensive shrinkage of the collagen fibrils, and narrower hybrid layers. Experimental BisGMA adhesives provide the proof of concept that relatively hydrophobic resins may be coupled to acid-etched dentin by increasing its hydrophobic characteristics via ethanol replacement. They should be further optimized before clinical application.