1,2-Dipalmitoyl-<i>sn</i>-glycero-3-phosphocholine (DPPC)-Rich Domain Formation in Binary Phospholipid Vesicle Membranes: Two-Dimensional Nucleation and Growth

Decades of study have probed phase transitions in model phospholipid bilayers and vesicles, especially in the context of the equilibrium phase diagram. Critical to the response of vesicles to environmental triggers, to the ultimate domain morphology, and to the approach to equilibrium (or not), we present here a study of domain formation in vesicles, focusing on a mechanism by which the cooling rate, tension, and composition affect the first appearance (nucleation) and subsequent growth of solid membrane domains. Employing a popular mixed membrane model based on DOPC and DPPC (1,2-dioleoyl-<i>sn</i>-glycero-3-phosphocholine and 1,2-dipalmitoyl-<i>sn</i>-glycero-3-phosphocholine, respectively), we examined phase separation in giant two-component vesicles that were cooled from the one-phase fluid (L_α) region of the phase diagram into a region of fluid (L_α)–solid coexistence. At moderate and low membrane tensions, cooling produced solid DPPC-rich domains appearing as compact patches or irregular hexagons and likely with a P_β′ (ripple) arrangement. (The compact solid domains in this study differed distinctly from striped domains in vesicles of the same composition, in terms of molecular organization and conditions of first appearance during cooling.) The amounts of these solid domains were shown to adhere to the lever arm rule for a tie line on the phase diagram, with a solid composition near 95 mol % DPPC. The nucleation of the compact solid domains occurred in a short period, followed by rapid addition of ordered molecules to the nucleated domains, excluding tracer dye. The two-dimensional nucleation density of these compact solid domains (in the range of 10^–2–10^–1 μm^–2) was found to increase with the cooling rate (equivalent to the quench depth) with a greater than linear dependence. The 2-D nucleation density was also seen to decrease with membrane tension, presumably because membrane tension increases the line tension around a domain that opposes nucleation. A sigmoidal dependence of the nucleation density on the DPPC concentration was also found. With cooling rates in excess of ∼1 °C/min, solid domains persisted down to room temperature, likely passing from a preferred equilibrium to a local equilibrium with continued cooling. As a result of the persistence of the originally nucleated domains and the conservation of DPPC in the membrane, we observed an increasingly greater number of smaller domains with increased cooling rates. The domains in these vesicles were compact or hexagonal-shaped in contrast to flower-shaped dendritic domains in the same membrane system in a supported membrane configuration

Photoelectrochemical Water Splitting of CuInS₂ Photocathode Collaborative Modified with Separated Catalysts Based on Efficient Photogenerated Electron–Hole Separation

Accelerating the separation and transfer of photogenerated carriers of a photoelectrode is vital to achieve a substantial performance increase for the photoelectrochemical (PEC) water splitting. In this paper, a CuInS₂ photocathode collaborative modified with separated cocatalyst layers including top Pt layer and bottom FeOOH layer is first fabricated to ameliorate PEC water splitting. The FeOOH layer can utilize holes from the CuInS₂ layer and then transfer holes through the conductive glass and wire to the counter electrode. The Pt layer can collect and transfer electrons from the CuInS₂ layer to the surface for water reduction. The collaborative FeOOH and Pt ameliorate effectively the hole and electron separation so as to improve PEC performances. An improved photocurrent density of ITO/FeOOH/CuInS₂/Pt photocathode reaches −6.79 mA·cm^–2 at −0.4 V vs RHE. Moreover, this study will be instructive for the design of efficient photocathode used in photoelectrochemical water splitting

Enhancement of Energy Density in the BOPP-Based Sandwich-Structured Film by the Synergistic Effect of BaTiO₃@Polyaniline Hybrid Dielectric Fillers

A series of polyaniline-coated BaTiO3 (BaTiO3@PANI) hybrid dielectric fillers were prepared through the in situ oxidative polymerization of aniline. The morphology of the hybrid fillers can be controlled by the ratio of aniline and BaTiO3 particles. Mulberry-like and core–shell BaTiO3@PANI composite particles are prepared successfully. The two kinds of dielectric fillers were introduced into the poly(vinylidene fluoride) (PVDF) matrix separately or simultaneously. The dielectric loss can be suppressed by the synergetic effect of these two hybrid fillers while enhancing the dielectric constant at the same time. The finite element simulation results showed that the surface morphology of adjacent hybrid fillers played an important role in the dielectric performance. The fillers were introduced in the biaxially oriented polypropylene (BOPP)-based sandwich-structured film; specifically, the outer layer was BOPP and the middle layer was the composites consisting of chlorinated polypropylene (CPP)/PVDF blends and the hybrid fillers. The energy storage density of the sandwich-structured film was improved significantly compared to that of the BOPP film. The highest discharge energy density was 7.31 J/cm3 at 450 MV/m, and the charge–discharge efficiency was 77.3% with 30 wt % hybrid fillers in the middle layer

Table1_TFRC–RNA interactions show the regulation of gene expression and alternative splicing associated with IgAN in human renal tubule mesangial cells.pdf

Introduction: IgA nephropathy (IgAN) is the most common primary glomerular disease (PGD) which could progress to renal failure and is characterized by aberrant IgA immune complex deposition. Transferrin receptor1 (TFRC), an IgA receptor, is a potential RNA binding protein (RBP) which regulates expression of genes positively associated with the cell cycle and proliferation and is involved in IgAN. Molecular mechanisms by which TFRC affects IgAN development remain unclear.Methods: In this study, TFRC was overexpressed in human renal tubular mesangial cells (HRMCs) and RNA-sequencing (RNA-seq) and improved RNA immunoprecipitation sequencing (iRIP-seq) were performed. The aim was to identify potential RNA targets of TFRC at transcriptional and alternative splicing (AS) levels.Results: TFRC-regulated AS genes were enriched in mRNA splicing and DNA repair, consistent with global changes due to TFRC overexpression (TFRC-OE). Expression of TFRC-regulated genes potentially associated with IgAN, including CENPH, FOXM1, KIFC1, TOP2A, FABP4, ID1, KIF20A, ATF3, H19, IRF7, and H1-2, and with AS, CYGB, MCM7 and HNRNPH1, were investigated by RT-qPCR and iRIP-seq data analyzed to identify TFRC-bound RNA targets. RCC1 and RPPH1 were found to be TFRC-bound RNA targets involved in cell proliferation.Discussion: In conclusion, molecular TFRC targets were identified in HRMCs and TFRC found to regulate gene transcription and AS. TFRC is considered to have potential as a clinical therapeutic target.</p

Table1_Electro-optic response of bipolar nematic liquid crystal confined in oblate spheroid.DOCX

Electro-optic response of liquid crystals (LCs) relies on the molecular reorientation of LCs under external electric field and is important for a wide spectrum of applications. Here, we uncover an interesting electro-optic response of 5CB nematic LC confined in an oblate spheroid and subjected to external electric field. Under the planar anchoring, the nematic LC spheroid adopts a bipolar structure with the bipolar axis laid in the horizontal film plane. When a threshold electric field EF, is applied, the bipolar structure reorients from the horizontal configuration (LC molecules align along long axis direction) to the vertical configuration (LC molecules align along short axis direction), involving the competition of elastic energy, surface anchoring energy and electric field energy. In contrast to bipolar nematic LC droplets, the vertical configuration does not relax to the low-energy horizontal configuration after removing E; we argue that is due to the oblate shape of the nematic LC spheroid, which traps the bipolar structure in a local energy minimum. We use continuum simulation to demonstrate the detailed response and the reorientation dynamics of bipolar nematic spheroids under E field, showing consistent results with the experiments and confirming the proposed switching mechanism. Nevertheless, the vertical configuration of the bipolar structure could relax to the low-energy horizontal configuration by thermal cycling. Our studies provide clear experimental results that show the characteristics of the electro-optic response of oblate LC spheroids, which have both fundamental and practical implications.</p

The Schizophrenia-Related Protein Dysbindin-1A Is Degraded and Facilitates NF-Kappa B Activity in the Nucleus

<div><p>Dystrobrevin-binding protein 1 (<i>DTNBP1</i>), a gene encoding dysbindin-1, has been identified as a susceptibility gene for schizophrenia. Functioning with partners in synapses or the cytoplasm, this gene regulates neurite outgrowth and neurotransmitter release. Loss of dysbindin-1 affects schizophrenia pathology. Dysbindin-1 is also found in the nucleus, however, the characteristics of dysbindin in the nucleus are not fully understood. Here, we found that dysbindin-1A is degraded in the nucleus via the ubiquitin-proteasome system and that amino acids 2-41 at the N-terminus are required for this process. By interacting with p65, dysbindin-1A promotes the transcriptional activity of NF-kappa B in the nucleus and positively regulates MMP-9 expression. Taken together, the data obtained in this study demonstrate that dysbindin-1A protein levels are highly regulated in the nucleus and that dysbindin-1A regulates transcription factor NF-kappa B activity to promote the expression of MMP-9 and TNF-α.</p></div

Sensitive Glycoprotein Sandwich Assays by the Synergistic Effect of In Situ Generation of Raman Probes and Plasmonic Coupling of Ag Core–Au Satellite Nanostructures

Sensitive surface-enhanced Raman scattering (SERS) assays of glycoproteins have been proposed using <i>p</i>-aminothiophenol (PATP)-embedded Ag core–Au satellite nanostructures modified with <i>p</i>-mercaptophenylboronic acid (PMBA) and the self-assembled monolayer of PMBA on a smooth gold-coated wafer. The apparent Raman probe PATP on the surfaces of the Ag cores underwent a photodimerization to generate 4,4′-dimercaptoazobenzene (DMAB) in situ upon excitation of laser, and the in situ generated DMAB acted as the actual Raman probe with considerably strong SERS signals, which was further enhanced by the plasmonic coupling of the Ag core–Au satellite nanostructures due to the synergistic effect. The sandwich assays of glycoproteins showed high sensitivity and excellent selectivity against nonglycoproteins. The Ag core–Au satellite SERS nanostructures can be used for highly sensitive SERS assays of other analytes

NAC blocked the rotenone-induced microglial activation.

<p>(A) BV2 cells treated with 1 µM rotenone for 24 hours or 1 µg/mL LPS for 24 hours or co-treated with 5 mM NAC and either 1 µM rotenone for 24 hours or 1 µg/mL LPS for 24 hours. The TNFα levels in the culture media of the treated BV2 cells were measured by ELISA. (B) BV2 cells were treated with as indicated in (A). Then, the cells were lysed, and the lysates were immunoblotted with the indicated antibodies. The activated IL-1β cleaved by caspase-1 is indicated as cleaved IL-1β.</p

Additional file 1: of Investigating the Co-Adsorption Behavior of Nucleic-Acid Base (Thymine and Cytosine) and Melamine at Liquid/Solid Interface

Supporting information available. The optimized results of molecular dimers formed by three kinds of building blocks and the binding energies for molecular dimers. This information is available free of charge via the Internet or from the author. (DOCX 508 kb

NAC blocked activation of the rotenone-induced NF-κB signaling pathway.

<p>(A) BV2 cells treated with 1 µM rotenone for 6 hours or 1 µg/mL LPS for 1 hour or co-treated with 5 mM NAC and either 1 µM rotenone for 6 hours or 1 µg/mL LPS for 1 hour. The cells were immunoblotted with anti-IκB antibodies. Tubulin served as the loading control. (B) BV2 cells treated with 1 µM rotenone for 6 hours or 1 µg/mL LPS for 1 hour or co-treated with 5 mM NAC and either 1 µM rotenone for 6 hours or 1 µg/mL LPS for 1 hour. The cells were fixed and labeled with DAPI (blue) and anti-p65 antibodies (red). The scale bar represents 10 µm. (C) The cytoplasmic and nuclear fractions from the BV2 cells that were treated as indicated in (B) were subjected to immunoblot analysis with anti-p65 antibodies. GAPDH served as the marker for the cytoplasmic fraction, and Max served as the marker for the nuclear fraction.</p