Revealing the synergistic effect of Ni single atoms and adjacent 3d metal doped Ni nanoparticles in electrocatalytic CO2 reduction.

Herein, we report the successful fabrication of a series of transition metal doped Ni nanoparticles (NPs) coordinated with Ni single atoms in nitrogen-doped carbon nanotubes (denoted as Ni1+NPsM-NCNTs, M = Mn, Fe, Co, Cu and Zn; Ni1 = Ni single atom). X-ray absorption fine structure reveals the coexistence of Ni single atoms with Ni-N4 coordination and NiM NPs. When applied for electrocatalytic CO2RR, the Ni1+NPsM-NCNT compounds show the Faradaic efficiency of CO (FECO) with a volcano-like tendency of Mn < Fe ≈ Co < Zn < Cu, in which the Ni1+NPsCu-NCNT exhibits the highest FECO of 96.92%, a current density of 171.25 mA cm-2 and a sustainable stability over 24 hours at a current density of 100 mA cm-2, outperforming most reported examples in the literature. Detailed experiments and theoretical calculations reveal that for Ni1+NPsCu-NCNTs, the electron transfer from NiCu NPs to Ni single atoms strengthens the adsorption of *COOH intermediates. Moreover, the d-band center of Ni-N in Ni1+NPsCu-NCNT is upshifted, providing stronger binding with the reaction intermediates of *COOH, whereas the NiCu NPs increase the Gibbs free energy change of the Volmer step, suppressing the competitive HER.

Ultrathin NiV Layered Double Hydroxide for Methanol Electrooxidation: Understanding the Proton Detachment Kinetics and Methanol Dehydrogenation Oxidation.

Electrochemical methanol oxidation reaction (MOR) is regarded as a promising pathway to obtain value-added chemicals and drive cathodic H2 production, while the rational design of catalyst and in-depth understanding of the structure-activity relationship remains challenging. Herein, the ultrathin NiV-LDH (u-NiV-LDH) with abundant defects is successfully synthesized, and the defect-enriched structure is finely determined by X-ray adsorption fine structure etc. When applied for MOR, the as-prepared u-NiV-LDH presents a low potential of 1.41 V versus RHE at 100 mA cm-2, which is much lower than that of bulk NiV-LDH (1.75 V vs RHE) at the same current density. The yield of H2 and formate is 98.2% and 88.1% as its initial over five cycles and the ultrathin structure of u-NiV-LDH can be well maintained. Various operando experiments and theoretical calculations prove that the few-layer stacking structure makes u-NiV-LDH free from the interlayer hydrogen diffusion process and the hydrogen can be directly detached from LDH laminate. Moreover, the abundant surface defects upshift the d-band center of u-NiV-LDH and endow a higher local methanol concentration, resulting in an accelerated dehydrogenation kinetics on u-NiV-LDH. The synergy of the proton detachment from the laminate and the methanol dehydrogenation oxidation contributes to the excellent MOR performance of u-NiV-LDH.

Association of seizures with COVID-19 infection in underage during the pandemic: A systematic review and meta-analysis.

OBJECTIVE: Coronavirus disease 2019 (COVID-19) is a contagious infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that has caused worldwide transmission. The aim of this systematic review and meta-analysis was to investigate the morbidity and characteristics of seizures after SARS-CoV-2 infection in underage (≤18 y) and to provide valuable reference material for subsequent clinical treatment. METHODS: PubMed/MEDLINE, Cochrane, and EMBASE databases were searched up to 10th May 2023. We utilized the search strategy of medical subject headings combined with entry terms to search all related literatures. RESULTS: The meta-analysis was performed according to PRISMA reporting guidelines. Risk of bias was assessed using the Newcastle-Ottawa Scale (NOS) and the Agency for Healthcare Research and Quality (AHRQ). A total of 12 articles were selected, including 4153 subjects and 333 seizure-prone minor patients with COVID-19. The morbidity of seizures after SARS-CoV-2 infection in immature patients was approximately 8.2 (95 % CI, 4.7%-12.4 %). By subgroup analysis, we know that the morbidity of male, Americas, with fever and first occurrence of seizures were 4.2% (95 % CI, 0.4-10.5 %), 4.6 % (95 % CI, 0.4 %-11.7 %), 5.4 % (95 % CI, 2.6 %-9.1 %) and 3.7 % (95 % CI, 0.7 %-8.2 %), respectively. Generalized seizures are the main type of seizures (80.6 %). CONCLUSIONS: Seizures can be caused by SARS-CoV-2 infection in underage groups, with a pooled morbidity of 8.2% and a higher morbidity in females, in African regions, in febrile groups and during 2022-2023. In addition, generalized seizures being the predominant seizure type.

Pd Loaded NiCo Hydroxides for Biomass Electrooxidation: Understanding the Synergistic Effect of Proton Deintercalation and Adsorption Kinetics.

The key issue in the 5-hydroxymethylfurfural oxidation reaction (HMFOR) is to understand the synergistic mechanism involving the protons deintercalation of catalyst and the adsorption of the substrate. In this study, a Pd/NiCo catalyst was fabricated by modifying Pd clusters onto a Co-doped Ni(OH)2 support, in which the introduction of Co induced lattice distortion and optimized the energy band structure of Ni sites, while the Pd clusters with an average size of 1.96 nm exhibited electronic interactions with NiCo support, resulting in electron transfer from Pd to Ni sites. The resulting Pd/NiCo exhibited low onset potential of 1.32 V and achieved a current density of 50 mA/cm2 at only 1.38 V. Compared to unmodified Ni(OH)2 , the Pd/NiCo achieved an 8.3-fold increase in peak current density. DFT calculations and in situ XAFS revealed that the Co sites affected the conformation and band structure of neighboring Ni sites through CoO6 octahedral distortion, reducing the proton deintercalation potential of Pd/NiCo and promoting the production of Ni3+ -O active species accordingly. The involvement of Pd decreased the electronic transfer impedance, and thereby accelerated Ni3+ -O formation. Moreover, the Pd clusters enhanced the adsorption of HMF through orbital hybridization, kinetically promoting the contact and reaction of HMF with Ni3+ -O.

Photocatalytic Oxidative Coupling of Ethane to n-Butane Using CO2 as a Soft Oxidant over NiTi-Layered Double Hydroxide.

Selective conversion of ethane (C2 H6 ) to high-value-added chemicals is a very important chemical process, yet it remains challenging owing to the difficulty of ethane activation. Here, a NiTi-layered double hydroxide (NiTi-LDH) photocatalyst is reported for oxidative coupling of ethane to n-butane (n-C4 H10 ) by using CO2 as an oxidant. Remarkably, the as-prepared NiTi-LDH exhibits a high selectivity for n-C4 H10 (92.35%) with a production rate of 62.06 µmol g-1 h-1 when the feed gas (CO2 /C2 H6 ) ratio is 2:8. The X-ray absorption fine structure (XAFS) and photoelectron characterizations demonstrate that NiTi-LDH possesses rich vacancies and high electron-hole separation efficiency, which can promote the coupling of C2 H6 to n-C4 H10 . More importantly, density functional theory (DFT) calculations reveal that ethane is first activated on the oxygen vacancies of the catalyst surface, and the C─C coupling pathway is more favorable than the C─H cleavage to C2 H4 or CH4 , resulting in the high production rate and selectivity for n-C4 H10 .

Coexistence of Au single atoms and Au nanoparticles on NiAl-LDH for selective electrooxidation of benzyl alcohol to benzaldehyde.

Introducing different active sites into heterogeneous catalysts provides new prospects to address the challenges in single-atom catalysis. Herein, the Au single atoms together and the Au nanoparticles were loaded onto NiAl-LDH by a facile impregnation-reduction method for the first time, resulting in the formation of Au1+n-NiAl-LDH, in which abundant Au single atoms are located around the Au nanoparticles with ∼5 nm size. When applied in the electrocatalytic benzyl alcohol oxidation reaction (BAOR), the as-prepared Au1+n-NiAl-LDH exhibits a remarkable selectivity of 91% and 177.63 µmol for benzaldehyde in 5 hours, while in contrast examples using solely Au single atom loaded NiAl-LDH (Au1-NiAl-LDH) and solely Au nanoparticle loaded NiAl-LDH (Aun-NiAl-LDH) can only realize 87.36 µmol production (75% selectivity) and 48.90 µmol production (28% selectivity) of benzaldehyde, respectively. Such a dramatic difference can be attributed to the synergistic effects of Au single atoms and Au nanoparticles. DFT calculation results reveal that for Au1+n-NiAl-LDH, Au single atoms promote the dehydrogenation capacity of LDH laminates, while Au nanoparticles offer adsorption sites for the electrophilic attachment of benzyl alcohol.

Enabling Specific Benzene Oxidation by Tuning the Adsorption Behavior on Au Loaded MgAl Layered Double Hydroxides.

Direct and selective oxidation of benzene to phenol is a long-term goal in industry. Although great efforts have been made in homogenous catalysis, it still remains a huge challenge to drive this reaction via heterogeneous catalysts under mild conditions. Herein, a single-atom Au loaded MgAl-layered double hydroxide (Au1 -MgAl-LDH) with a well-defined structure, in which the Au single atoms are located on the top of Al3+ with Au-O4 coordination as revealed by extended x-ray-absorption fine-structure (EXAFS)and density-functional theory (DFT)calculation is reported. The photocatalytic results prove the Au1 -MgAl-LDH is capable of driving benzene oxidation reaction with O2 in water, and exhibits a high selectivity of 99% for phenol. While contrast experiment shows a ≈99% selectivity for aliphatic acid with Au nanoparticle loaded MgAl-LDH (Au-NP-MgAl-LDH). Detailed characterizations confirm that the origin of the selectivity difference can be attributed to the profound adsorption behavior of substrate benzene with Au single atoms and nanoparticles. For Au1 -MgAl-LDH, single Au-C bond is formed in benzene activation and result in the production of phenol. While for Au-NP-MgAl-LDH, multiple AuC bonds are generated in benzene activation, leading to the crack of CC bond.

Metal-N-Heterocyclic Carbene Chemistry Directed toward Metallosupramolecular Synthesis and Beyond.

ConspectusAs versatile, modular, and strongly coordinating moieties in organometallic compounds, N-heterocyclic carbenes (NHCs) have led to numerous breakthroughs in transition-metal catalysis, main group chemistry, and organocatalysis. In contrast, the chemistry of NHC-based metallosupramolecular assemblies, in which discrete individual components are held together via metal (M)-CNHC bonds, has been underdeveloped. Integrating NHCs into supramolecular assemblies would endow them with some unforeseen functions. However, one of the most critical challenges is seeking an appropriate combination of the rigid CNHC-M-CNHC units with the resulting topologies and applications. Toward this goal, for the last decade we have focused on the development of M-NHC directed toward metallosupramolecular synthesis. This Account aims to summarize our contributions to the application of M-NHC chemistry toward supramolecular synthesis from structural design to postassembly modification (PAM) and their functional applications since integrating NHCs into supramolecular assemblies has garnered much attention among organometallic, photochemical, and supramolecular researchers. While presenting representative examples of NHC-based architectures, we try to illustrate the purposes and concepts behind the systems developed to aid the rational approach to the design and fabrication of complex assemblies and M-NHC-templated photochemical reactions.We present synthetic approaches for new architectures by the rational design of starting NHC precursors, including the poly-NHC-based mechanically interlocked metallacages and the heteroleptic architectures based on electronic complementary and self-sorting mechanisms. The structural regulation of poly-NHC-based architectures with increasing topological complexity is elaborated on by selective combinations of tetraphenylethylene (TPE) units, NHC backbones, and N-wingtip substituents in a controllable manner.Subsequently, we move to elucidating an M-NHC-templated PAM approach that leads to functional organic cages featuring polyimidazolium/triazolium groups of different shapes and sizes that are difficult to access using alternative organic approaches. These organic cages possess well-defined cavities, and their in situ-generated NHC sites are ideal platforms for stabilizing metal nanoparticles (MNPs) within their cavities for improved catalytic performance.Finally, we demonstrate how to design supramolecular M-NHC templates to synthesize cyclobutane derivatives in homogeneous solutions in a catalytic fashion. Selected examples of M-NHC template-dependent structural transformations and photoreactions are discussed. Their applications in molecular recognition, aggregation-induced emission (AIE), cell imaging, anticancer activity, radical chemistry, and stimuli-responsive materials are also described.Taken together, M-NHC-templated approaches have proven to be powerful methods for constructing diverse architectures with functional applications. The development of this methodology is still in its infancy, with tremendous growth potential and a promising future. We believe that this Account will guide researchers to design fascinating and valuable M-carbene species for diverse applications.

Insight into the Mechanism of Cd2+ Removal by MgAl Layered Double Hydroxides with Different Host-Guest Interactions.

Layered double hydroxides (LDHs) have shown great potential as adsorbents for the removal of heavy metals. Nevertheless, how the host-guest interactions of LDHs affect the removal mechanism remains to be less explored. Herein, CO3 2- /NO3 - /SO4 2- /Cl- intercalated MgAl-LDHs with different host-guest interactions were fabricated and their removal mechanism for Cd2+ was investigated. The removal capacity increased in the order of MgAl-CO3 (127.3 mg/g)

Promotive role of eukaryotic translation initiation factor 4A isoform 3 in ovarian cancer cell growth and aerobic glycolysis through the pyruvate dehydrogenase kinase 4 signaling.

Ovarian cancer (OC) represents one of the most detrimental gynecological malignancies. RNA-binding protein eukaryotic translation initiation factor 4A isoform 3 (EIF4A3) is well-regarded as a definitive oncogene that contributes to the development of multiple malignant tumors. This study sought to elucidate the molecular mechanism of EIF4A3 in OC growth and aerobic glycolysis by regulation of pyruvate dehydrogenase kinase 4 (PDK4) mRNA stability. We determined the EIF4A3 and PDK4 expression levels in OC cell lines and normal ovarian epithelial cells, and subsequently evaluated the cell viability and colony formation by cell counting kit-8 and colony formation assays. The degree of cell aerobic glycolysis was evaluated by measurements of lactic acid production, glucose intake, adenosine triphosphate level, extracellular oxygen consumption, and protein levels of pyruvate kinase isozymes M2 and hexokinase-2. Afterwards, we verified the binding of EIF4A3 and PDK4 mRNA via RNA immunoprecipitation, and determined the mRNA stability after actinomycin D treatment. Finally, a series of rescue experiments was performed with pcDNA3.1-PDK4. EIF4A3 and PDK4 were upregulated in OC cells. Silencing EIF4A3 obstructed cell proliferation and aerobic glycolysis, while the same was annulled by EIF4A3 overexpression. Mechanically, EIF4A3 could bind to PDK4 mRNA to stabilize its mRNA and upregulate its protein levels. PDK4 overexpression inverted the inhibitory role of silencing EIF4A3 in proliferation and aerobic glycolysis. Overall, our findings highlighted that EIF4A3 induced OC progression by stabilizing PDK4 mRNA.

Highly Efficient Circularly Polarized Luminescence from Chiral Au13 Clusters Stabilized by Enantiopure Monodentate NHC Ligands.

Chiral Au nanoclusters have promising application prospects in chiral sensing, asymmetric catalysis, and chiroptics. However, enantiopure superatomic homogold clusters with crystallographic structures emitting bright circularly polarized luminescence (CPL) remain challenging. In this study, we designed chiral N-heterocyclic carbenes (NHCs), and for the first time enantioselectively synthesized a pair of monovalent cationic superatomic Au13 clusters. This new enantiomeric pair of clusters has a quasi-C2 symmetric core and exhibited CPL with an unprecedent solution-state quantum yield (QY) of 61 % among those of the atomically precise Au nanoclusters. DFT calculations provided insights into the circular dichroism behavior, and revealed the origin of CPL from superatomic Au clusters. This work opens a new avenue for developing novel homochiral nanoclusters using chiral NHC ligands and provides fundamental understanding of the origin of the chiroptics of metal clusters.

Revealing the Kinetic Balance between Proton-Feeding and Hydrogenation in CO2 Electroreduction.

Electrocatalytic reduction of CO2 to high-value-added chemicals provides a feasible path for global carbon balance. Herein, the fabrication of NiNP x @NiSA y -NG (x,y = 1, 2, 3; NG = nitrogen-doped graphite) is reported, in which Ni single atom sites (NiSA ) and Ni nanoparticles (NiNP ) coexist. These NiNP x @NiSA y -NG presented a volcano-like trend for maximum CO Faradaic efficiency (FECO ) with the highest point at NiNP2 @NiSA2 -NG in CO2 RR. NiNP2 @NiSA2 -NG exhibited ≈98% of maximum FECO and a large current density of -264 mA cm-2 at -0.98 V (vs. RHE) in the flow cell. In situ experiment and density functional theory (DFT) calculations confirmed that the proper content of NiSA and NiNP balanced kinetic between proton-feeding and CO2 hydrogenation. The NiNP in NiNP2 @NiSA2 -NG promoted the formation of H* and reduced the energy barrier of *CO2 hydrogenation to *COOH, and CO desorption can be efficiently facilitated by NiSA sites, thereby resulting in enhanced CO2 RR performance.

Dual Engineering of Lattice Strain and Valence State of NiAl-LDHs for Photoreduction of CO2 to Highly Selective CH4.

Converting CO2 to clean-burning fuel such as natural gas (CH4 ) with high activity and selectivity remains to be a grand challenge due to slow kinetics of multiple electron transfer processes and competitive hydrogen evolution reaction (HER). Herein, the fabrication of surfactants (C11 H23 COONa, C12 H25 SO4 Na, C16 H33 SO4 Na) intercalated NiAl-layered double hydroxides (NiAl-LDH) is reported, resulting in the formation of LDH-S1 (S1 = C11 H23 COO- ), LDH-S2 (S2 = C12 H25 SO4 - ) and LDH-S3 (S3 = C16 H33 SO4 - ) with curved morphology. Compared with NiAl-LDH with a 1.53% selectivity of CH4 , LDH-S2 shows higher selectivity of CH4 (83.07%) and lower activity of HER (3.84%) in CO2 photoreduction reaction (CO2 PR). Detailed characterizations and DFT calculation indicates that the inherent lattice strain in LDH-S2 leads to the structural distortion with the presence of VNi/Al defects and compressed MOM bonds, and thereby reduces the overall energy barrier of CO2 to CH4 . Moreover, the lower oxidation states of Ni in LDH-S2 enhances the adsorption of intermediates such as OCOH* and *CO, promoting the hydrogenation of CO to CH4 . Therefore, the coupling effect of both lattice strain and electronic structure of the LDH-S2 significantly improves the activity and selectivity for CO2 PR.

VO4 -Modified Layered Double Hydroxides Nanosheets for Highly Selective Photocatalytic CO2 Reduction to C1 Products.

The conversion of CO2 into high-value added chemicals driven by solar energy is an effective way to solve environmental problems, which is, however, largely restricted by the competition reaction of the hydrogen evolution reaction (HER) and easy electron-hole recombination, etc. Herein, VO4 -supported ultrathin NiMgV-layered double hydroxide (V/NiMgV-LDH) nanosheets are successfully fabricated, and the extended X-ray absorption fine structure (EXAFS) and density function theory (DFT) calculations reveal that VO4 species are located on the top of V atoms in the NiMgV-LDH laminate. The V/NiMgV-LDH is proved to be highly efficient for the photocatalytic CO2 reduction reaction (CO2 PR) with high selectivity of 99% for C1 products and nearly no HER (<1%) takes place under visible light. Contrast experiments using NiMgV-LDH as the catalyst for CO2 PR show a CO selectivity of 71.40% and a H2 selectivity of 28.11%. Such excellent performance of V/NiMgV-LDH can be attributed to the following reasons: 1) the V/NiMgV-LDH modulates the band structure and promotes the separation of electrons and holes; 2) strong bonding between V/NiMgV-LDH and CO* and H* facilitates the hydrogenation to form CH4 and inhibits the formation of by-product H2 at the same time.

Rational Regulation of Electronic Structure in Layered Double Hydroxide Via Vanadium Incorporation to Trigger Highly Selective CO2 Photoreduction to CH4.

To realize excellent selectivity of CH4 in CO2 photoreduction (CO2 PR) is highly desirable, yet which is challenging due to the limited active sites for CH4 generation and severe electron-hole recombination on photocatalysts. Herein, based on the theoretically calculated effects of vanadium incorporation into the laminate of layered double hydroxides (LDHs), V into NiAl-LDH to synthesize a series of LDHs with various V contents is introduced. NiV-LDH is revealed to afford a high CH4 selectivity (78.9%), and extremely low H2 selectivity (only 0.4%) under λ > 400 nm irradiation. By further tuning the molar ratio of Ni to V, a CH4 selectivity of as high as 90.1% is achieved on Ni4 V-LDH, and H2 is completely prohibited on Ni2 V-LDH. Fine structural characterizations and comprehensive optical and electrochemical studies uncover V incorporation creates the lower-valence Ni species as active sites for generating CH4 , and enhances the generation, separation, and transfer of photogenerated carriers.

Water-Soluble Self-Assembled Cage with Triangular Metal-Metal-Bonded Units Enabling the Sequential Selective Separation of Alkanes and Isomeric Molecules.

The selective separation of structurally similar aliphatic/aromatic hydrocarbons is an essential goal in industrial processes. In this study, we report the synthesis of a water-soluble (Tr2M3)4L4 (Tr = cycloheptatrienyl ring; M = metal; L = organosulfur ligand) molecular cage (1) via self-assembly of the water-soluble acceptor tripalladium sandwich species [(Tr2Pd3)(CH3CN)][NO3]2 and the attachment onto L of solubilizing methoxyethoxy appendants to be utilized in an energy-friendly alternative approach to the separation of structurally similar molecules under ambient conditions. Cage 1, comprising a hydrophobic inner cavity, exhibited good solubility and stability in aqueous media. It also demonstrated excellent performance in the sequential separation of alkanes (C6-C9), xylene, and other disubstituted benzene isomers and cis/trans-decalin.

N-heterocyclic carbene-stabilized metal nanoparticles within porous organic cages for catalytic application.

Tuning the surface-embellishing ligands of metal nanoparticles (NPs) is a powerful strategy to modulate their morphology and surface electronic and functional features, impacting their catalytic activity and selectivity. In this work, we report the design and synthesis of a polytriazolium organic cage PIC-T, capable of stabilizing PdNPs within its discrete cavity. The obtained material (denoted Pd@PCC-T) is highly durable and monodispersed with narrow particle-size distribution of 2.06 ± 0.02 nm, exhibiting excellent catalytic performance and recyclability in the Sonogashira coupling and tandem reaction to synthesize benzofuran derivatives. Further investigation indicates that the modulation of N-heterocyclic carbene sites embedded in the organic cage has an impact on NPs' catalytic efficiency, thus providing a novel methodology to design superior NP catalysts.

Supramolecular-controlled regioselective photochemical [4 + 4] cycloaddition within Cp*Rh-based metallarectangles.

Photochemical reactions are vital synthetic means for the synthesis of natural products and highly strained molecules. However, it remains an immense challenge to control the chemo- and regioselectivity in the photoreactions of anthracene derivatives while maintaining high reactivity. Herein, we report the synthesis of two photoactive metallarectangles 1a and 1b by coordination-driven self-assembly of 2,6- and 2,7-bifunctionalized anthracenes with a half-sandwich rhodium template. By taking advantage of the rhodium template, the anthracene groups within the metallarectangles can be preorganized in a parallel fashion and exclusively undergo a photochemical [4 + 4] cycloaddition. As a result, the syn-photodimers were obtained in quantitative yields under irradiation at 365 nm. The photocycloaddition of metallarectangles 1a and 1b was found to be reversible via photo- and thermal cleavage reactions, even after repeating three times. Furthermore, pure organic photodimers 3a and 3b, which are difficult to synthesize by conventional organic methods, can be readily dissociated from the metalloassemblies in high yields.

Advanced Anode Materials for Sodium-Ion Batteries: Confining Polyoxometalates in Flexible Metal-Organic Frameworks by the "Breathing Effect".

Polyoxometalates (POMs) have shown great potential in sodium-ion batteries (SIBs) due to their reversible multielectron redox property and high ionic conductivity. Currently, POM-based SIBs suffer from the irreversible trapping and sluggish transmission kinetics of Na+. Herein, a series of POMs/metal-organic frameworks (MOFs)/graphene oxide (GO) (MOFs = MIL-101, MIL-53, and MIL-88B; POM = [PMo12O40]3-, denoted as PMo12) composites are developed as SIB anode materials for the first time. Unlike MIL-101 with large pore structures, the pores in flexible MIL-53 and MIL-88B swell spontaneously upon the accommodation of PMo12. Particularly, the PMo12/MIL-88B/GO composites deliver an excellent specific capacity of 214.2 mAh g-1 for 600 cycles at 2.0 A g-1, with a high initial Coulombic efficiency (ICE) of 51.0%. The so-called "breathing effect" of flexible MOFs leads to the relatively tight confinement space for PMo12, which greatly modulates its electronic structure, affects the adsorption energy of Na+, and eventually reduces the trapping of sodium ions. Additionally, the straight and multidimensional channels in MIL-88B significantly accelerate ion diffusion, inducing favored energetic kinetics and thus generating high-rate performance.

Sinomenine inhibits macrophage M1 polarization by downregulating α7nAChR via a feedback pathway of α7nAChR/ERK/Egr-1.

BACKGROUND: Sinomenine (SIN) is an anti-inflammatory drug that has been used for decades in China to treat arthritis. In a previous study, SIN acted on α7 nicotinic acetylcholine receptor (α7nAChR) to inhibit inflammatory responses in macrophages, which indicates a new anti-inflammatory mechanism of SIN. However, the level of α7nAChR was increased in the inflammatory responses and was downregulated by SIN in vitro, so the underlying mechanisms of SIN acting on α7nAChR remain unclear. PURPOSE: To analyze the role of α7nAChR in inflammation and the effect and mechanism of SIN regulation of α7nAChR. METHODS: The effects of SIN on α7nAChR in endotoxemic mice and LPS-stimulated macrophages were observed. Nicotine (Nic) was used as a positive control, and berberine (Ber) was used as a negative control targeting α7nAChR. The antagonists of α7nAChR, α-bungarotoxin (BTX) and mecamylamine (Me), were used to block α7nAChR. In RAW264.7 macrophage cells in vitro, α7nAChR short hairpin RNA (shRNA) was used to knock down α7nAChR. Macrophage polarization was analyzed by the detection of TNF-α, IL-6, iNOS, IL-10, Arg-1, and Fizz1. U0126 was used to block ERK phosphorylation. The cytokines α7nAChR, ERK1/2, p-ERK1/2 and Egr-1 were detected. RESULTS: SIN decreased the levels of TNF-α, IL-6 and the expression of α7nAChR increased by LPS in endotoxemic mice. The above effects of SIN were attenuated by BTX. In the α7nAChR shRNA transfected RAW264.7 cells, compared with the control, α7nAChR was knocked down, and M1 phenotype markers (including TNF-α, IL-6, and iNOS) were significantly downregulated, whereas M2 phenotype markers (including IL-10, Arg-1, and Fizz1) were significantly upregulated when stimulated by LPS. SIN inhibited the expression of p-ERK1/2 and the transcription factor Egr-1 induced by LPS in RAW264.7 cells, and the above effects of SIN were attenuated by BTX. The expression of α7nAChR was suppressed by U0126, which lessened the expression of p-ERK1/2 and Egr-1. CONCLUSIONS: SIN acts on α7nAChR to inhibit inflammatory responses and downregulates high expression of α7nAChR in vivo and in vitro. The increase of α7nAChR expression is correlated with inflammatory responses and participates in macrophage M1 polarization. SIN downregulates α7nAChR via a feedback pathway of α7nAChR/ERK/Egr-1, which contributes to inhibiting macrophage M1 polarization and inflammatory responses.