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The key to optimizing energy-consuming catalytic conversions lies in acquiring a fundamental understanding of the nature of the active sites and the mechanisms at an atomically precise level, while it is challenging due to the complexity of real-life conditions.

Identifying the structural configurations of precursors for CO dissociation is fundamentally interesting and industrially important in the fields of

The increasingly stringent emission regulations make it urgent to get a fundamental understanding on the catalytic behaviors of rhodium, the most efficient component in three-way catalysts (TWCs) to convert NOx into N2. Herein, the catalytic conversion of NO and CO into N2 and CO2 by gas-phase rhodium-aluminum oxide species (RhAlO0–3 and RhAl2O1–4) was identified by mass spectrometry and quantum chemical calculations. This finding represents a significant step in the field of gas-phase catalysis, given that only elementary reactions for this conversion are commonly observed because it is extremely challenging to rupture the strong N–O bond and couple the N–N bond as well as drive the resulting product to oxidize CO. It emphasized that a polarized Rh–Al bond in gas-phase species is indispensable and the RhAlO0,1 and RhAl2O1,2 species with direct Rh–Al bonding can be involved in catalytic NO reduction by CO.

We experimentally identify the gas-phase species Rh2− that can drive the reverse water–gas shift (RWGS, CO2 + H2 → CO + H2O) reaction. The generation of a gas-phase H2O molecule and [Rh2(CO)ads]− at room temperature was identified and the only elementary step that requires extra energy to complete the catalysis is CO desorption.

Fundamental understanding of the nature of active sites in real-life water gas shift (WGS) catalysts that can convert CO and H2O into CO2 and H2 is crucial to engineer related catalysts performing under ambient conditions. Herein, we identified that the WGS reaction can be, in principle, catalyzed by rhodium-manganese oxide clusters Rh2MnO1,2- in the gas phase at room temperature. This is the first example of the construction of such a potential catalysis in cluster science because it is challenging to discover clusters that can abstract the oxygen from H2O and then supply the anchored oxygen to oxidize CO. The WGS reaction was characterized by mass spectrometry, photoelectron spectroscopy, and quantum-chemical calculations. The coordinated oxygen in Rh2MnO1,2- is paramount for the generation of an electron-rich Mn+-Rh- bond that is critical to capture and reduce H2O and giving rise to a polarized Rh+-Rh- bond that functions as the real redox center to drive the WGS reaction.

The generation and characterization of multiple metal-metal (M-M) bonds between early and late transition metals is vital to correlate the nature of multiple M-M bonds with the related reactivity in catalysis, while the examples with multiple M-M bonds have been rarely reported. Herein, we identified that the quadruple bonding interactions were formed in a gas-phase ion IrV+ with a dramatically short Ir-V bond. Oxidation of four CO molecules by IrVO4+ is a highly exothermic process driven by the generation of stable products IrV+ and CO2, and then IrV+ can be oxidized by N2O to regenerate IrVO4+. This finding overturns the general impression that vanadium oxide clusters are unwilling to oxidize multiple CO molecules because of the strong V-O bond and that at most two oxygen atoms can be supplied from a single V-containing cluster in CO oxidation. This study emphasizes the potential importance of heterobimetallic multiple M-M bonds in related heterogeneous catalysis.

Laser ablation generated CoCDn- (n = 0-4) anions were mass selected and then reacted with CO2 in an ion trap reactor. The reactions were characterized by mass spectrometry and quantum chemical calculations. The experimental results demonstrated that the CoC- anion can convert CO2 into CO. In contrast, the bare Co- anion is inert toward CO2. Coordinated D ligands can modify the reactivity of CoCD1-4- in which CoCD1-3- can reduce CO2 into CO selectively and CoCD4- can only adsorb CO2. The crucial roles of the coordinated C and D ligands to tune the reactivity of CoCDn- (n = 0-4) toward CO2 were rationalized by theoretical calculations. Note that the hydrogenation process that is usually observed in the reactions of gas-phase metal hydrides with CO2 is completely suppressed for the reactions CoCDn- + CO2. This study provides insights into the molecular-level origin for the observations that CO can be selectively generated from CO2 catalyzed by cobalt-containing carbides in heterogeneous catalysis.

Previous reports on daptomycin's adverse drug reactions (ADRs) have been insufficient, often because of limited data. Pharmacovigilance risk signal detection is innovative and has been applied to the safety monitoring and reevaluation of drugs post-marketing.The study aimed to promote safe daptomycin prescribing by mining and evaluating the daptomycin ADR signals from the US Food and Drug Administration Adverse Event Reporting System (FAERS).A disproportionality analysis (reporting odds ratio ROR and proportional reporting ratio PRR) was utilized for FAERS data mining from the first quarter of 2004 to the second quarter of 2021 (the most recent quarterly data at the time of the study). Preferred Terms of ADR reports were categorized by System Organ Class (SOC) based on the Medical Dictionary for Regulatory Activities.This study retrieved 12,221 cases within the reporting period. A total of 140 repetitive signals were obtained by ROR and PRR, of which 53 new ADR signals were not recorded in the drug labels/datasheets. The top three ADR reports were "blood creatine phosphokinase elevation" (ROR, 56.66, 95% confidence interval (CI) 51.07-62.87, PRR 51.94), "eosinophilic pneumonia" (ROR 696.71, 95%CI 603.21-804.70, PRR 657.57), and "rhabdomyolysis" (ROR 22.85, 95%CI 19.94-26.18, PRR 21.83). The highest ROR of "antimicrobial susceptibility test resistant" was found at 9808.14. Reports of rare adverse events, such as "necrotizing fasciitis and compartment syndrome," have emerged. The significant SOCs were "Infections and Infestations" and "Investigations."New daptomycin ADR signals were detected. Clinicians should monitor these potential ADRs in patients receiving daptomycin.

Gas-phase studies on catalytic CO oxidation by O2 mediated with gold-containing heteronuclear metal oxide clusters are vital to obtain the structure-reactivity relationship of supported gold catalysts, while it is challenging to trigger the reactivity of clusters with closed-shell electronic structure in O2 activation. Herein, we identified that CO oxidation by O2 can be catalyzed by the AuTi2 O4-6- clusters, among which AuTi2 O4- with closed-shell electronic structure can effectively activate O2 . The reactions were characterized by mass spectrometry and quantum chemical calculations. Theoretical calculations showed that in the initial stage of O2 activation, the Ti2 O4 moiety in AuTi2 O4- contributes dominantly to activate O2 into superoxide (O2- ⋅) without participation of the Au atom. In subsequent steps, the intimate charge transfer interaction between Au and the Ti2 O4 moiety drives the direct dissociation of the O2- ⋅ unit.

Nitrogen (N2) fixation is a challenging and vital issue in chemistry. Inspired by the fact that the active sites of nitrogenases are polynuclear metal sulfide clusters, the reactivity of gas-phase metal sulfide clusters toward N2 has received considerable attention to gain fundamental insights into nitrogen fixation. Herein, neutral tantalum sulfide clusters have been prepared and their reactivity toward N2 has been investigated by mass spectrometry in conjunction with density functional theory (DFT) calculations. The experimental results showed that Ta3Sn (n = 0-3) could adsorb N2, while Ta3S4 was inert to N2. The DFT calculations revealed that the complete cleavage of the N≡N bond on the trinuclear metal center in the Ta3S0-3/N2 reaction systems was overall barrierless under thermal collision conditions. The sulfur ligands can facilitate the approaching of N2 toward the metal center but weaken the electron-donating ability of the metal center. The inertness of Ta3S4 is ascribed to the electron-deficient state of Ta3 in Ta3S4 and the least effective orbital interaction in the Ta3S4/N2 couple. This study provides new insights into the ligand effect on the interaction of the metal clusters with N2.

Cleavage of the triple N≡N bond by metal clusters is of fundamental interest and practical importance in nitrogen fixation. Previous studies of N≡N bond cleavage by gas-phase metal clusters emphasized the importance of the dinuclear metal centers. Herein, the dissociative adsorption of N2 and subsequent C-N coupling on trinuclear carbide cluster anions V3C4- under thermal collision conditions have been characterized by employing mass spectrometry (collision induced dissociation), cryogenic photoelectron imaging spectroscopy, and quantum chemistry calculations. A theoretical analysis identified a crucial adsorption intermediate with N2 bonded with the V3 metal core in the end-on/side-on/side-on (ESS) mode, which most likely enables the facile cleavage of the N≡N bond. Such a vital N2 coordination in the ESS mode is a result of symmetry-matched interactions between the occupied orbitals of the metal core and both of the two empty π* orbitals of N2. Furthermore, carbon ligands also play a considerable role in enhancing the reactivity of the metal core toward N2. This study strongly suggests a new mechanism of N≡N bond cleavage by gas-phase metal clusters.

Metals with high oxidation states (HOSs) (e.g., +V to +X) are of great interest to chemists, although it is challenging to trigger the reactivity of metals with HOSs, because they are usually highl...

Adverse cardiac remodeling after myocardial infarction (MI) is associated with extremely high mortality rates worldwide. Although optimized medical therapy, Preservation of lusitropic and inotropic function and protection against adverse remodeling in ventricular structure remain relatively frequent. This study demonstrated that Andrographolide (Andr) significantly ameliorated adverse cardiac remodeling induced by myocardial infarction and improves contractile function in mice with LAD ligation compared with the control group. Briefly, Andr markedly attenuated cardiac fibrosis and relieved inflammation after myocardial infarction. Specifically, Andr significantly blocked oxidative stress and the nuclear translocation of p-P65 following myocardial infarction. At the mechanistic level, antioxidant effect of Andr was achieved through strengthening antioxidative stress capacity and attributed to the activation of Nrf2/HO-1 Signaling. Consistently, H9C2 administrated with Andr showed a decreased oxidative stress caused by hypoxia precondition, but treatment with specific Nrf2 inhibitor (ML385) or the silence of Nrf2 blunted the activation of Nrf2/HO-1 Signaling and removed the protective effects of Andr in vitro. Thus, we suggest that Andr alleviates adverse cardiac remodeling following myocardial infarction through enhancing Nrf2 signaling pathway.

Zileuton has been demonstrated to be an anti-inflammatory agent due to its well-known ability to inhibit 5-lipoxygenase (5-LOX). However, the effects of zileuton on cardiac remodeling are unclear. In this study, the effects of zileuton on pressure overload-induced cardiac remodeling were investigated and the possible mechanisms were examined. Aortic banding was performed on mice to induce a cardiac remodeling model, and the mice were then treated with zileuton 1 week after surgery. We also stimulated neonatal rat cardiomyocytes with phenylephrine (PE) and then treated them with zileuton. Our data indicated that zileuton protected mice from pressure overload-induced cardiac hypertrophy, fibrosis, and oxidative stress. Zileuton also attenuated PE-induced cardiomyocyte hypertrophy in a time- and dose-dependent manner. Mechanistically, we found that zileuton activated PPARα, but not PPARγ or PPARθ, thus inducing Keap and NRF2 activation. This was confirmed with the PPARα inhibitor GW7647 and NRF2 siRNA, which abolished the protective effects of zileuton on cardiomyocytes. Moreover, PPARα knockdown abolished the anticardiac remodeling effects of zileuton in vivo. Taken together, our data indicate that zileuton protects against pressure overload-induced cardiac remodeling by activating PPARα/NRF2 signaling.

Juvenile idiopathic arthritis (JIA) is a chronic inflammatory disease that includes seven heterogeneous subgroups with different prognoses. In particular, polyarticular JIA (pJIA) has a longer period of active disease and a poorer prognosis. Tumor necrosis factor (TNF)-alpha inhibitors are effective in patients with pJIA, but the therapeutic regimen remains controversial. Here, we performed a single-center study to determine the potential correlation between TNF-alpha inhibitor (infliximab) therapy and outcomes in these patients. Clinical data of 40 pJIA patients were collected at our center from January 1, 2010 to January 1, 2018, and patients were grouped according to the timing of infliximab therapy. The erythrocyte sedimentation rate (ESR), the number of joints with active disease, and the 27-point juvenile arthritis disease activity score (JADAS-27) were analyzed. The ESR, the active joint count, and the JADAS-27 decreased significantly in all groups after 3 months (P = 0.041/0.415/0.008, 0.022/0.030/

Understanding the heterogeneous oxidation of isoprene is crucial to discover the missing sink of the atmospheric isoprene. Iron oxide nanoparticles dominate the most abundant type of anthropogenic ...

Prevention of ATP binding cassette transporter A1 (ABCA1)-dependent cholesterol efflux leads to lipid accumulation in macrophages and atherosclerosis development. C1q tumor necrosis factor-related protein 1 (CTRP1), a conserved paralog of adiponectin, has been shown to aggravate atherosclerosis via its pro-inflammatory property. However, very little is known about its effects on ABCA1 expression and macrophage lipid accumulation. In the current studies, we found that CTRP1 down-regulated ABCA1 expression, inhibited cholesterol efflux to apoA-I and promoted lipid accumulation in THP-1 macrophage-derived foam cells. Forkhead box O1 (FoxO1), a transcriptional repressor of ABCA1, was identified as a direct target of miR-424-5p. Mechanistically, CTRP1 attenuated miR-424-5p levels and then augmented FoxO1 expression in the nucleus, which led to down-regulation of ABCA1 expression and inhibition of cholesterol efflux. In conclusion, these findings suggest that CTRP1 restrains cholesterol efflux and facilitates macrophage lipid accumulation through the miR-424-5p/FoxO1/ABCA1 signaling pathway, thereby providing a novel mechanistical insight into its pro-atherosclerotic action. This article is protected by copyright. All rights reserved.

Laser ablation generated CoCD

Doped metal oxide catalysts have important applications in heterogeneous catalysis, whereas the fundamental effects of doping on the reactivity of catalysts are elusive. Herein, benefiting from the study of a series of atomic clusters MVO5– (M = V–Zn) in catalytic CO oxidation by molecular O2 under thermal collision conditions, the crucial effects of doping on the electronic structure and then the catalytic reactivity of MVO5– were successfully rationalized by using mass spectrometry and theoretical calculations. We defined the energy gap of active orbitals that are closely related to electron transfer in MVO5– during CO oxidation. It was discovered that such an energy gap can modulate reaction thermodynamics, whereas the orbital overlap of MVO5– with CO controls the kinetics. The doped clusters MVO5– (M = Cr–Zn) have reduced energy gaps than that in host V2O5–, and doping can modify the orbital overlap of MVO5– (M = Cr–Zn) with CO. Only the MnVO5– and ZnVO5– clusters that have rational energy gaps and pr...

Oxidation of CO by gas-phase atomic clusters is being actively studied to understand the molecular-level mechanisms of heterogeneous CO oxidation over related catalytic surfaces. However, it is experimentally challenging to study CO oxidation by neutral heteronuclear metal oxide clusters because of the difficulty of cluster ionization and detection without fragmentation. Herein, the neutral AuVO $_{2-4}$ clusters were experimentally generated and their reactions with CO and O $_2$ were studied. The experimental results showed that CO adsorption is the dominant channel on the interactions of AuVO $_4$ and AuVO $_3$ with CO, and AuVO $_2$ can pick up an O $_2$ molecule to generate AuVO $_4$ . Theoretical studies indicated that the oxidation of the trapped CO in AuVO $_{3,4}$ CO into CO $_2$ is exothermic while the reaction barriers have to be overcome at the elevated temperatures. A catalytic cycle for CO oxidation by AuVO $_{2-4}$ is proposed.

The thermal reaction of diatomic gold boride cation AuB+ with methane has been studied by using state-of-the-art mass spectrometry in conjunction with density functional theory calculations. The AuB+ ion can activate a methane molecule to produce exclusively the free hydrogen atom, an important intermediate in hydrocarbon transformation. This result is different from the reactivity of AuC+ and CuB+ counterparts with methane in previous studies. The AuC+ cation mainly transforms methane into ethylene. The CuB+ reaction system principally generates the free hydrogen atoms, but it also gives rise a portion of ethylene-like product H2B−CH2. The B atom of AuB+ is the active site to activate methane. The strong relativistic effect on gold plays an important role for the product selectivity. The mechanistic insights obtained from this study provide guidance for rational design of active sites with high product selectivity toward methane activation.

Oxide supported gold catalysts (e.g., Au/TiO2) are of great significance in heterogeneous catalysis owing to their extraordinary catalytic activity. Study of heteronuclear metal oxide clusters (HMOCs, e.g., Au xTi yO z q) is an important way to uncover the molecular-level mechanisms of gold catalysis in the related heterogeneous catalytic systems. However, the current studies of HMOCs are focused on charged clusters with little attention paid to neutral species. The reactivity study of neutral HMOCs is vital to have a comprehensive understanding of heterogeneous catalysis, but it is experimentally challenging because of the difficulty of cluster ionization and detection without fragmentation. Herein, benefiting from a homemade time-of-flight mass spectrometer coupled with a vacuum ultraviolet laser system, the reactivity of neutral Au1-doped titanium oxide clusters AuTi2O3-6 in catalytic CO oxidation by O2 has been successfully identified. The mechanistic details of the catalysis have been elucidated by quantum chemistry calculations. The crucial roles of the mobile AuCO species that can facilitate not only the process of CO oxidation but also the process of O2 activation have been discovered in the cluster catalysis. The fascinating results are of substantial importance to understand the mechanisms of CO oxidation over Au/TiO2, one type of the best studied gold catalysts.

Cationic gold has been frequently identified as a suitable reactive species for activating methane in condensed-phase studies. However, it is far from clear how the coordination site manipulates the activity of such species. Herein, by anchoring AuI on silicon oxide cluster supports of variable sizes, the site-specific methane activation by AuI -Ox has been clarified by mass spectrometry in conjunction with quantum chemistry calculations. An unexpected mechanistic switch in C-H activation was identified for the cluster anions Au(SiO2 )n O- (n=1-3) that selectively activate one of the four C-H bonds of methane with different reaction efficiencies: a low efficiency was observed for the two-fold-coordinated gold ion (AuI, 2f ), which was anchored on an AuSiO3- or AuSi2 O5- cluster, through an oxidative addition mechanism (a homolytic process), and high efficiency was observed for the one-fold-coordinated gold ion (AuI, 1f ), which was supported on an AuSi3 O7- cluster, through Lewis acid/base pairs mechanism (AuI, 1f ⋅⋅⋅O2- , a heterolytic process). Fine regulation of the 5d orbital level of the Au atom by the oxygen ligands accounted for the mechanistic difference between AuI, 2f and AuI, 1f species. The mechanistic understanding of the reactivity of AuI -Ox at a strictly molecular level can be used to clarify the dissimilar activity of gold anchored on different oxide supports.

The use of CH4 and CO2 to produce value-added chemicals via direct C-C coupling is a challenging chemistry problem because of the inertness of these two molecules. Herein, mass spectrometric experiments and high-level quantum-chemical calculations have identified the first diatomic species (CuB+ ) that can couple CH4 with CO2 under thermal collision conditions to produce ketene (H2 C=C=O), an important intermediate in synthetic chemistry. The order to feed the reactants (CH4 and CO2 ) is important and CH4 should be firstly fed to produce the C2 product. Molecular-level mechanisms including control of product selectivity have been revealed for coupling of CH4 with CO2 under mild conditions.

Exercise, as a common non-drug intervention, is one of several lifestyle choices known to reduce the risk of cancer. Mitochondrial division has been reported to play a key role in the occurrence and transformation of hepatocellular carcinoma (HCC). This study investigated whether exercise could regulate the occurrence and development of HCC through mitosis.Bioinformatics technology was used to analyze the expression level of dynamin-related protein 1 (DRP1), a key protein of mitochondrial division. The effects of DRP1 and DRP1 inhibitor (mdivi-1) on the proliferation and migration of liver cancer cells BEL-7402 were observed using cell counting kit-8, plate colony formation, transwell cell migration, and scratch experiments. Enzyme-linked immunosorbent assay, Western blot and real-time polymerase chain reaction were used to detect the expression of DRP1 and its downstream phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathway. A treadmill exercise intervention was tested in a nude mouse human liver cancer subcutaneous tumor model expressing different levels of DRP1. The size and weight of subcutaneous tumors in mice were detected before and after exercise.The expression of DRP1 in liver cancer tissues was significantly upregulated compared with normal liver tissues (P 0.001). The proliferation rate and the migration of BEL-7402 cells in the DRP1 over-expression group were higher than that in the control group. The mdivi-1 group showed an inhibitory effect on the proliferation and migration of BEL-7402 cells at 50 μmol/L. Aerobic exercise was able to inhibit the expression of DRP1 and decrease the size and weight of subcutaneous tumors. Moreover, the expression of phosphorylated PI3K (p-PI3K) and phosphorylated AKT (p-AKT) decreased in the exercise group. However, exercise could not change p-PI3K and p-AKT levels after knocking down DRP1 or using mdivi-1 on subcutaneous tumor.Aerobic exercise can suppress the development of tumors partially by regulating DRP1 through PI3K/AKT pathway.

Kcnq1 overlapping transcript 1 (kcnq1ot1), an imprinted antisense lncRNA in the kcnq1 locus, acts as a potential contributor to cardiovascular disease, but its role in atherosclerosis remains unknown. The aim of this study was to explore the effects of kcnq1ot1 on atherogenesis and the underlying mechanism. Our results showed that kcnq1ot1 expression was significantly increased in mouse aorta with atherosclerosis and lipid-loaded macrophages. Lentivirus-mediated kcnq1ot1 overexpression markedly increased atherosclerotic plaque area and decreased plasma HDL-C levels and RCT efficiency in apoE−/− mice fed a Western diet. Upregulation of kcnq1ot1 also reduced the expression of miR-452-3p and ABCA1 but increased HDAC3 levels in mouse aorta and THP-1 macrophages. Accordingly, kcnq1ot1 overexpression inhibited cholesterol efflux and promoted lipid accumulation in THP-1 macrophages. In contrast, kcnq1ot1 knockdown protected against atherosclerosis in apoE−/− mice and suppressed lipid accumulation in THP-1 macrophages. Mechanistically, kcnq1ot1 enhanced HDAC3 expression by competitively binding to miR-452-3p, thereby inhibiting ABCA1 expression and subsequent cholesterol efflux. Taken together, these findings suggest that kcnq1ot1 promotes macrophage lipid accumulation and accelerates the development of atherosclerosis through the miR-452-3p/HDAC3/ABCA1 pathway.

C1q tumor necrosis factor-related protein 12 (CTRP12), a conserved paralog of adiponectin, is closely associated with cardiovascular disease. However, little is known about its role in atherogenesis. The aim of this study was to examine the influence of CTRP12 on atherosclerosis and explore the underlying mechanisms. Our results showed that lentivirus-mediated CTRP12 overexpression inhibited lipid accumulation and inflammatory response in lipid-laden macrophages. Mechanistically, CTRP12 decreased miR-155-5p levels and then increased its target gene liver X receptor α (LXRα) expression, which increased ATP binding cassette transporter A1 (ABCA1)- and ABCG1-dependent cholesterol efflux and promoted macrophage polarization to the M2 phenotype. Injection of lentiviral vector expressing CTRP12 decreased atherosclerotic lesion area, elevated plasma high-density lipoprotein cholesterol levels, promoted reverse cholesterol transport (RCT), and alleviated inflammatory response in apolipoprotein E-deficient (apoE−/−) mice fed a Western diet. Similar to the findings of in vitro experiments, CTRP12 overexpression diminished miR-155-5p levels but increased LXRα, ABCA1, and ABCG1 expression in the aortas of apoE−/− mice. Taken together, these results suggest that CTRP12 protects against atherosclerosis by enhancing RCT efficiency and mitigating vascular inflammation via the miR-155-5p/LXRα pathway. Stimulating CTRP12 production could be a novel approach for reducing atherosclerosis.

Gas-phase studies on catalytic CO oxidation by O

Nitrogen (N

To observe the effect of low-frequency electrical acupoint stimulation on gastrointestinal motility in patients undergoing radical gastrectomy, and its impact on regulation of inflammatory response, so as to evaluate its clinical value.A total of 177 patients undergoing radical gastrectomy were randomly divided into conventional group (After the treatment, the first postoperative flatus and defecation time in the LEAS, FTS and FTS＋LEAS groups were significantly shorter than those of the conventional group (FTS combined with LEAS is superior to simple FTS or LEAS treatment in shortening the first flatus and defecation time and promoting the recovery of gastrointestinal motility function in patients undergoing radical gastrectomy, which may be associated with its effect in alleviating postoperative inflammatory responses.

Biochanin A (BCA), a dietary isoflavone extracted from red clover and cabbage, has been shown to antagonize hypertension and myocardial ischemia/reperfusion injury. However, very little is known about its role in atherogenesis. The aim of this study was to observe the effects of BCA on atherosclerosis and explore the underlying mechanisms. Our results showed that administration of BCA promoted reverse cholesterol transport (RCT), improved plasma lipid profile, and decreased serum proinflammatory cytokine levels and atherosclerotic lesion area in apoE-/- mice fed a Western diet. In THP-1 macrophage-derived foam cells, treatment with BCA upregulated ATP-binding cassette (ABC) transporter A1 (ABCA1) and ABCG1 expression and facilitated subsequent cholesterol efflux and diminished intracellular cholesterol contents by activating the peroxisome proliferator-activated receptor γ (PPARγ)/liver X receptor α (LXRα) and PPARγ/heme oxygenase 1 (HO-1) pathways. BCA also activated these two signaling pathways to inhibit the secretion of proinflammatory cytokines. Taken together, these findings suggest that BCA is protective against atherosclerosis by inhibiting lipid accumulation and inflammatory response through the PPARγ/LXRα and PPARγ/HO-1 pathways. BCA may be an attractive drug for the prevention and treatment of atherosclerotic cardiovascular disease.

The hydrogenation of carbon dioxide into value-added chemicals is of great importance for CO2 recycling. However, the underlying mechanism of CO2 hydrogenation remains elusive owing to the lack of experimental evidence for the formation of the C–H bond. Herein, the gas-phase reaction of copper hydride anion Cu2H2– with CO2 at variable temperatures (∼300–560 K) was investigated. Metal hydrides are the ideal models to study the nature of C–H bond formation in CO2 hydrogenation, while the related studies are scarcely reported, particularly for the hydrogenation reactions at temperatures above 300 K. The generation of formate (HCO2–) attached on product CuH2CO2– was identified by temperature-dependent mass spectrometric experiments and density functional theory calculations. Temperature played crucial roles to fine-tune the product selectivity, from Cu2H2CO2– that dominates the room-temperature reaction into CuH2CO2– at elevated temperatures. The nature behind the temperature-dependent product selectivity and...

Identification of molecular-level mechanisms of methane activation is very important in order to transform the most stable alkane molecule into value-added chemicals. Herein, by employing a homemade time-of-flight mass spectrometer coupled with a vacuum ultraviolet (VUV) laser system, the reactions of neutral heteronuclear metal oxide clusters AuxAlyOz (x = 1, 2) with CH4 have been investigated. The interesting channel of Au2Al2O3H+ production was observed for the interaction of a Au2Al2O3 cluster with CH4 after VUV ionization, suggesting that the methyl radical was generated. Combined with the theoretical calculations, this study proposes that VUV ionization of the neutral adsorption complex (Au2Al2O3CH4) creates an active cation (Au2Al2O3CH4+)* to induce C–H bond activation and the methyl radical formation. The photochemistry of this cluster study provides molecular-level insights into the interactions between methane and active sites in related photocatalytic processes.

Investigation on the reactivity of atomic clusters represents an important approach to discover new species to activate and transform methane, the most stable alkane molecule. While a few types of transition metal species have been found to be capable of cleaving the C–H bond of methane, methane activation by the transition metal boride species has not been explored yet. This study reports that vanadium boride cluster cations VBn+ (n = 3–6) can dehydrogenate methane under thermal collision conditions. The mechanistic details of the efficient reactions have been elucidated by quantum chemistry calculations on the VB3+ reaction system. Compared to the non-polar bare B3 cluster, the B3 moiety in VB3+ can be polarized by the V+ cation and thus its reactivity toward methane can be much enhanced. This study provides new insights into the rational design of boron-based catalysts for methane activation.

Pre-harvest sprouting (PHS) occurs frequently in most of the wheat cultivation area worldwide, which severely reduces yield and end-use quality, resulting in substantial economic loss. In this study, quantitative trait loci (QTL) for PHS resistance were mapped using an available high-density single nucleotide polymorphism (SNP) and simple sequence repeat (SSR) genetic linkage map developed from a 269 recombinant inbred lines (RILs) population of Yanda 1817×Beinong 6. Using phenotypic data on two locations (Beijing and Shijiazhuang, China) in two years (2012 and 2013 harvesting seasons), five QTLs, designated as QPhs.cau-3A.1, QPhs.cau-3A.2, QPhs.cau-5B, QPhs.cau-4A, and QPhs.cau-6A, for PHS (GP) were detected by inclusive composite interval mapping (ICIM) (LOD≥2.5). Two major QTLs, QPhs.cau-3A.2 and QPhs.cau-5B, were mapped on 3AL and 5BS chromosome arms, explaining 6.29–21.65% and 4.36–5.94% of the phenotypic variance, respectively. Precise mapping and comparative genomic analysis revealed that the TaVp-1A flanking region on 3AL is responsible for QPhs.cau-3A.2. SNP markers flanking QPhs.cau-3A.2 genomic region were developed and could be used for introgression of PHS tolerance into high yielding wheat varieties through marker-assisted selection (MAS).

Oxide supported gold catalysts (e.g., Au/TiO