Tris­(4-isocyanatophenyl)­methane (TIPM) and N,N′-dimethylformamide react at room temperature with no externally added catalyst to yield polyisocyanurate (PIR) gels. The obtained PIR gels were converted to N- and S-doped porous carbon monoliths by thermal treatment at 1000 °C with elemental sulfur under inert conditions. The PIR linkage acts as precursor for carbon and nitrogen, and %S doping was varied by changing the concentrations of elemental sulfur during pyrolysis. The optimized concentration of sulfur (5.6%) into the carbon matrix displayed excellent oxygen reduction activity with direct four-electron transfer relative to its pristine counterparts by (1) introducing micro- and mesopores in addition to the already existing macropores by etching the carbon surface (confirmed by N2 sorption isotherms and microscopic images) with the increase in the external surface area providing more active centers and efficient diffusion of electrolyte ions, (2) providing more – C–S–C– active species than oxidized sulfur species (confirmed by XPS and FT-IR) with more oxygen adsorption sites, and (3) filling the micropores of the carbon as a monolayer, affording increased electronic conductivity to the amorphous carbon. This simple and facile method of incorporating N- and S- together into the porous carbon matrix can be considered as an alternate for nonprecious metal catalysts for oxygen reduction reaction.

We report the synthesis of lightweight, free-standing Ni-Fe@rGO porous interconnects by carbothermal reduction of Ni-FeOx using graphene oxide (GO) as the reducing agent. Here, we take advantage of the oxygen functionalities present in GO to aid in anchoring the metal ions followed by epoxide-assisted Ni-FeOx@GO network formation. When pyrolyzed under inert conditions, Ni-FeOx@GO networks were converted to Ni-Fe@rGO by simple carbothermal metal reduction at 800 °C. The Ni-Fe@rGO monoliths were found to be macroporous, electrically conducting, and electrocatalytic toward oxygen evolution reaction (OER). The monoliths exhibited excellent OER activity yielding a current density of 10 mA cm at an overpotential of 350 mV versus RHE, Tafel slope of 38 mV decade, and a TOF value of 50 s on par with the established Ni-Fe based electrocatalysts.

Abstract Ezrin, a membrane–cytoskeleton linker protein, plays an essential role in cell polarity establishment, cell migration, and division. Recent studies show that ezrin phosphorylation regulates breast cancer metastasis by promoting cancer cell survivor and promotes intrahepatic metastasis via cell migration. However, it was less characterized whether there are additional post-translational modifications and/or post-translational crosstalks on ezrin underlying context-dependent breast cancer cell migration and invasion. Here we show that ezrin is acetylated by p300/CBP-associated factor (PCAF) in breast cancer cells in response to CCL18 stimulation. Ezrin physically interacts with PCAF and is a cognate substrate of PCAF. The acetylation site of ezrin was mapped by mass spectrometric analyses, and dynamic acetylation of ezrin is essential for CCL18-induced breast cancer cell migration and invasion. Mechanistically, the acetylation reduced the lipid-binding activity of ezrin to ensure a robust and dynamic cycling between the plasma membrane and cytosol in response to CCL18 stimulation. Biochemical analyses show that ezrin acetylation prevents the phosphorylation of Thr567. Using atomic force microscopic measurements, our study revealed that acetylation of ezrin induced its unfolding into a dominant structure, which prevents ezrin phosphorylation at Thr567. Thus, these results present a previously undefined mechanism by which CCL18-elicited crosstalks between the acetylation and phosphorylation on ezrin control breast cancer cell migration and invasion. This suggests that targeting PCAF signaling could be a potential therapeutic strategy for combating hyperactive ezrin-driven cancer progression.

Imine terminated mesoporous silica nanoparticles (IMSNP) appear to be an effective mesoporous media with potential for multifarious applications such as catalytic support, effluent treatment, and sensors.