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The correct phagocytic activity of microglia is a prerequisite for maintaining homeostasis in the brain. In the analysis of mechanisms regulating microglial phagocytosis, we focused on the bromodomain and extraterminal domain (BET) proteins: Brd2, Brd3, and Brd4, the acetylation code readers that control gene expression in cooperation with transcription factors. We used pharmacological (JQ1) and genetic (siRNA) inhibition of BET proteins in murine microglial cell line BV2. Inhibition of BET proteins reduced the phagocytic activity of BV2, as determined by using a fluorescent microspheres-based assay and fluorescently labelled amyloid-beta peptides. Gene silencing experiments demonstrated that all brain-existing BET isoforms control phagocytosis in microglia. From a set of 84 phagocytosis-related genes, we have found the attenuation of the expression of 14: Siglec1, Sirpb1a, Cd36, Clec7a, Itgam, Tlr3, Fcgr1, Cd14, Marco, Pld1, Fcgr2b, Anxa1, Tnf, Nod1, upon BET inhibition. Further analysis of the mRNA level of other phagocytosis-related genes which were involved in the pathomechanism of Alzheimer's disease demonstrated that JQ1 significantly reduced the expression of Cd33, Trem2, and Zyx. Our results indicate the important role of BET proteins in controlling microglial phagocytosis; therefore, targeting BET may be the efficient method of modulating microglial activity. [ABSTRACT FROM AUTHOR]

Heterojunction engineering enables more versatile and higher performance systems than single components. In parallel with heterojunction engineering, defect engineering has emerged as a means of tailoring the optoelectronic properties of photoelectrodes. However, constructing effective and stable hybrid semiconductor heterojunctions is a challenging task under the strict requirements of band alignment, vacancy characteristics, and interface properties. Herein, the photoelectrochemical (PEC) reduction of CO2 to methanol is augmented by a novel approach explored by modeling the Fermi level in a multi‐interface architecture. The excellent PEC CO2 reduction activity is attributed to the formation of a high‐performance, energetically aligned multi‐interface system of CuO/Cu2O||rGO|h‐WO3|rGO (rGO = reduced graphene oxide layer). The overall performance of this hybrid, system strongly depends on the number of oxygen groups in rGO and the structural properties of rGO. Therefore, to construct an effective PEC system, numerous postsynthetic treatments are explored for their practicality and usefulness. The results reported herein clearly show that the best performance toward the CO2 photoreduction currents of 3 mA/cm2 at 0.00.1 V versus reversable hydrogen electrode (more than double that of the CuO/Cu2O system) has been reached for the semiconductor architecture containing two layers of rGO. [ABSTRACT FROM AUTHOR]

Electrodeposited SiO electrodes were shown to be photoactive and exhibit n- and p-type effects for electrodes placed in aqueous and organic solutions, respectively. As seen by Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron (XPS) spectroscopy, the mechanism of the electrodeposition included reactions with the used electrolyte as well as with traces of water as sources of oxygen and hydrogen. The lowest band gap energy ( E ) of the films of approximately 1.6 eV was observed for the film electrodeposited at −2.5 V in comparison to 1.9 eV for the films obtained at −2.25 and −2.75 V. The depth profiles of Si and O in the films were registered by XPS, secondary ion mass spectrometry (SIMS), and glow discharge optical emission spectroscopy (GD-OES), which showed that Si and O were relatively uniformly distributed across the entire layer of the film. The n-type photoactivity was associated with the evolution of oxygen from the aqueous solution, and the p-type was attributed to the reductive deterioration of the amorphous SiO deposit and simultaneous photodecomposition of the electrolyte. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Abstract: We report a low temperature, an electrochemical way of preparation of a photoanode made of n-type silicon oxide based films, at which surface photoelectrochemical oxygen evolution was observed with no need to deposit of other materials. Conditions of electrosynthesis, under which the electrochemical reduction of silicon chlorides in non aqueous solutions leads to silicone oxide based films are described. The photoactivity of prepared photo-anodes was reproducible and the observed photocurrent sustained for many hours. The most stable photocurrent was observed for films deposited at −2.7V. Water oxidation was observed while occurring at the onset potentials smaller than 0.2V comparing to the dark water splitting potential. The highest photocurrent was observed at −0.3V (thermodynamic value 1.02V vs. Ag wire), which means energy saving corresponding to ca. 1.3V. The results demonstrate that a low temperature electrodeposition of silicon oxide based films can be an alternative route for fabrication of photoanode for water photosplitting devices. [Copyright &y& Elsevier]