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Membrane fouling and the trade-off between membrane permeability and selectivity restrict the potential applications of membrane filtration for water treatment. ZIF-8 was found having great permeability and antibiofouling performance, but with issue on particle aggregation makes it difficult to achieve high ZIFs loading and fabricate a defect-free molecular sieving membrane in previous research. In this study, we formed a scalable antibiofouling surface with improved permeability and fouling resistance on a PEI-ZIF-PAA membrane using a layer-by-layer assembly technique. The synergistic effects of being sandwiched between two different polyelectrolyte layers with opposite charges endowed the ZIF nanoparticles with improved stability and scalability for membrane modification. The PEI-ZIF-PAA membrane exhibited a satisfactory water flux of 120.78 LMH, which was 46.97% higher than that of the pristine PES membrane. The normalized water flux loss was serious in the absence of ZIF-8, and the flux increased with the ZIF-8 concentration. Antifouling tests suggested that the PEI-ZIF-PAA membrane possessed good antifouling performance due to the much higher surface hydrophilicity and positive Lewis acid-base interactions with foulants. The HA rejection increased with the ZIF-8 concentration and reached a maximum of 92.1% in the presence of 1.00% (w/v) ZIF-8. The membrane regeneration was tested under physical and chemical cleaning with flux recovery rates of about 85% and 95%. XDLVO analysis showed that the total interaction energy between HA and the PEI-ZIF-8-PAA membrane was 26.45 mJ/m

C-reactive protein (CRP) is a major acute phase protein and inflammatory marker, the expression of which is largely liver specific and highly inducible. Enhancers are regulatory elements critical for the precise activation of gene expression, yet the contributions of enhancers to the expression pattern of CRP have not been well defined. Here, we identify a constitutively active enhancer (E1) located 37.7 kb upstream of the promoter of human CRP in hepatocytes. By using chromatin immunoprecipitation, luciferase reporter assay, in situ genetic manipulation, CRISPRi, and CRISPRa, we show that E1 is enriched in binding sites for transcription factors STAT3 and C/EBP-β and is essential for the full induction of human CRP during the acute phase. Moreover, we demonstrate that E1 orchestrates with the promoter of CRP to determine its varied expression across tissues and species through surveying activities of E1-promoter hybrids and the associated epigenetic modifications. These results thus suggest an intriguing mode of molecular evolution wherein expression-changing mutations in distal regulatory elements initiate subsequent functional selection involving coupling among distal/proximal regulatory mutations and activity-changing coding mutations.

Pharmaceuticals are necessary to be removed from environment. Herein TiO

Background Circulating levels of the systemic inflammation marker C-reactive protein (CRP) have been associated with increased risk and poor outcomes of many diseases, such as cardiovascular events and cancer. Accumulating evidence has indicated that the conformational rearrangement of human pentameric CRP (pCRP) to monomeric CRP (mCRP) is a prerequisite for participation in the pathogenesis. Therefore, determining the mechanism of the dissociation of pCRP into pro-inflammatory mCRP under physiological/pathological circumstances has been intriguing. Methods The effects of oxidative and acidic stress occurring in inflammation on pCRP were examined by electrophoresis, electron microscopy, protein fluorescence, neoepitope expression and endothelial cell responses. Results Reactive oxygen species (ROS) generated by the copper-hydrogen peroxide system could rapidly induce the dissociation of CRP at mild acidic pH within four hours, but not at physiological pH of 7.4. Meanwhile, mannitol, a ROS scavenger, could not protect against dissociation, which implied that local ROS from accessible histidine residues may be crucially beneficial to the formation of mCRP in a redox-balanced microenvironment. Furthermore, mCRP generated by ROS could be reduced by DTT, which indicated the exposure of functional motif aa35-47, and showed potent proinflammatory actions on endothelial cells, comparable to mCRP generated by urea. Conclusion dissociation of pCRP to mCRP could be rapidly induced by ROS from copper- hydrogen peroxide system in dependence on mildly acidic stress regardless of a redox-balanced microenvironment.

C-reactive protein (CRP) is a major human acute-phase reactant that is composed of five identical subunits. CRP dissociates into subunits at inflammatory loci forming monomeric CRP (mCRP) with substantially enhanced activities, which can be further activated by reducing the intra-subunit disulfide bond. However, conformational changes underlying the activation process of CRP are less well understood. Conformational changes accompanying the conversion of CRP to mCRP with or without reduction were examined with circular dichroism spectroscopy, fluorescence spectroscopy, electron microscopy, size-exclusion chromatography, and neoepitope expression. The conversion of CRP to mCRP follows a two-stage process. In the first stage, CRP dissociates into molten globular subunits characterized by intact secondary structure elements with greatly impaired tertiary packing. In the second stage, these intermediates completely lose their native subunit conformation and assemble into high-order aggregates. The inclusion of reductant accelerates the formation of molten globular subunits in the first step and promotes the formation of more compact aggregates in the second stage. We further show a significant contribution of electrostatic interactions to the stabilization of native CRP. The conformational features of dissociated subunits and the aggregation of mCRP may have a key impact on their activities.

The fouling of capacitive deionization (CDI) electrodes can adversely affect the CDI performance. One major foulant during water treatment relies on natural organic matter (NOM). A better understanding of the electroadsorption and electrochemical behavior of different groups NOM could clarify their relative contributions in electrode fouling. In this study, commercial sodium alginate (SA), humic acid (HA), and bovine serum albumin (BSA) were selected as representative model substances of NOM. During CDI process Salt ions were removed from brackish water during CDI and porous electrodes surfaces were covered by NOM to block the surface sites and micropores. After 50 CDI cycles, the salt adsorption capacity decreased by 78.2%, 47.6% and 66.0%, while the energy consumption increased by 213.6%, 63.3% and 129.1% for SA, HA and BSA, respectively. The charge efficiency diminished to 20.0%, 44.9% and 27.8% for SA, HA and BSA. The presence of NOM degraded the practical performances of porous activated carbons in terms of salt storage capacity, ion diffusion, and electron transport. Both SA and HA showed the worst impacts on the cathode, and BSA aggravated the oxidation process of the anode. The valuable information might be useful for future studies and applications.

The separation of oil/water emulsion has become a pressing worldwide problem. In this study, a novel type of photoinduced separation membrane was prepared via layer-by-layer (LBL) method of ZIF-8/GO composite. By integrating the unique physical and chemical properties of ZIF-8 and GO, the ZIF-8/GO membrane exhibits superior superoleophobicity under visible light and underwater anti-fouling for efficient oil rejection from water. We found that the ZIF-8/GO membrane permeation flux was 110 ± 6 L m−2 h−1 under light irradiation, which was higher than the permeation flux of membranes without irradiation (50 ± 6 L m−2 h−1). For toluene, the removal rate was about 100% at the first time, with new benzyl alcohol and benzaldehyde products detected in the filtrate, indicating that toluene was degraded on the ZIF-8/GO membrane surface. Continuous separation performed using filtration apparatus demonstrates a high separation capacity, with long-term membrane stability. The high water flux, high separation capacity and capacity for large-scale preparation of the ZIF-8/GO membrane, shows great potential for industrial application in the treatment of oil-containing wastewater.

Capacitive deionization (CDI) is considered as a potential water purification technology for electrochemical removal of the salt from aqueous solutions. However, the development of an electrode material with adequate electro adsorption rate and capacity is still a major challenge. In this study, a N and P-doped three-dimensional (3D) structure of graphene with high conductivity and capacitance for high performance CDI was synthesized and possessed tunable pore size through phosphoric acid activation. It had a large specific surface area of 567.14 m2 g−1 due to the 3D hierarchical porous structure and highly crosslinked networks of graphene sheets. This novel material also had a high specific capacitance (177.19 F g−1). High specific capacitance and interaction of micropores with mesopores improved the desalination capacity up to 20.93 mg g−1. Consequently, the materials with high specific surface area, better specific capacitance and tunable pore size can have a great potential for efficient and practical desalination applications.