The mechanism of the norrish type II reaction of α-keto-acids and esters

Methyl-α-keto-octanoate undergoes a Type II reaction to give pent-1-ene and photophysical measurements show that this and the Type II reactions of α-keto-acids occur, contrary to previous claims, from the excited singlet state.     

Effect of Silk Protein Processing on Drug Delivery from Silk Films

Sericin removal from the core fibroin protein of silkworm silk is a critical first step in the use of silk for biomaterial‐related applications, but degumming can affect silk biomaterial properties, including molecular weight, viscosity, diffusivity and degradation behavior. Increasing the degumming time (10, 30, 60, and 90 min) decreases the average molecular weight of silk protein in solution, silk solution viscosity, and silk film glass‐transition temperature, and increases the rate of degradation of a silk film by protease. Model compounds spanning a range of physical‐chemical properties generally show an inverse relationship between degumming time and release rate through a varied degumming time silk coating. Degumming provides a useful control point to manipulate silk's material properties.

     

Novel use of glow discharge optical emission spectroscopy (GDOES) to study corrosion of AA2024‐T3 in the presence and absence of inhibitors – part 3: investigating the effects of various proportions of inhibitor in the coating matrix or in nanocontainers

Elemental depth profiling by glow discharge optical emission spectroscopy has been used to characterize the corrosion products on AA2024‐T3. In previous work, the aluminium, oxygen and copper depth profiles were shown to provide information regarding surface roughening, the thickness of corroded layers and extent of copper de‐alloying/relocation. Nitrogen, sulfur, phosphorus and chromium depth profiles were examined in the hope of detecting inhibitor species within the corroded/altered layers after 5 h of exposure to a corrosive solution. In the present work, the study is extended to longer exposure time. The work presents a further study of the leaching of benzotriazole from the coating matrix or from nanocontainers during various times of exposure to a corrosive environment. Copyright © 2016 John Wiley & Sons, Ltd.     

Unexpected Mass Decoupling for 3He-4He Films on a Solid Hydrogen Substrate

Quartz oscillator measurements reveal new behavior in 3He-4He mixture films on a H2 substrate. For mixture films of total coverage greater than one monolayer, in addition to the expected Kosterlitz-Thouless transition, a second mass decoupling event is observed, which behaves differently from the Kosterlitz-Thouless transition.     

Dual anti-inflammatory and antiglycation propensities of a potentially novel class of functionalized fluoroquinolones

Promoted by elevated blood glucose concentrations in diabetes, glycation involves the nonenzymatic addition of reducing sugars and/or their reactive degradation products to amine groups on proteins. New synthetic approaches to 18 fluoroquinolones (FQs) have been developed on the basis of a promising antiglycation activity using 400μM methylglyoxal as the choice glucocytotoxicity concentration. Their anti-inflammatory and radical scavenging properties were elucidated in vitro. Intriguingly, FQs could exhibit an exceedingly more superior than or substantially comparable cytoprotection against methylglyoxal-induced carbonyl toxicity in RAW264.7 macrophages and antiglycation activity to aminoguanidine, as the reference compound. This kind of activity can suggestively be associated with the chelating properties possessed by the synthesized FQs as their DPPH radical scavenging activities proved to be significantly inferior to those of the reference compound, the ascorbic acid. The inhibitory bioactivities using the Griess assay were examined of the compounds against lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 macrophages. Selectively, compounds R-2TCBA , R-4FACBA , R-3TCBA , and R-4CLACBA exerted an exceedingly remarkable and superior anti-inflammatory effects (P < .001 vs indomethacin IC₅₀ value of 101.07 ± 2.2 μM) while R-4TCBA and T-4BrACBA were moderately more efficacious than indomethacin. Compounds T-4CLACBA and R-4BrACBA displayed comparable activity with indomethacin. None of the tested compounds and indomethacin exerted any cytotoxicity against RAW 264.7 mouse macrophages. FQs possess potent duality of antiglycation–anti-inflammatory capacities and are devoid of undesirable side effects. FQs can, therefore, serve as scaffolds for the development and designing of new clinical deglycation and antiglycation therapeutic agents.     

Diffuse abdominal angiomatosis

We present a rare case of diffuse abdominal angiomatosis occurring in a 19-year-old male; particular attention is paid to the MR imaging features of this disease process.     

Mechanistic insights into the inhibition mechanism of cysteine cathepsins by chalcone-based inhibitors—a QM cluster model approach

Structural Chemistry - Cathepsins are the most abundant cysteine proteases involved in many physiological processes. The imbalance between the natural cysteine protease inhibitors and cathepsins...