Publications by authors named "Jiao-Jiao Chen"

23 Publications

  • Page 1 of 1

Biochanin A Mitigates Atherosclerosis by Inhibiting Lipid Accumulation and Inflammatory Response.

Oxid Med Cell Longev 2020 11;2020:8965047. Epub 2020 Nov 11.

Department of Pathophysiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, 230032 Anhui, China.

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 (PPAR)/liver X receptor (LXR) and PPAR/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 PPAR/LXR and PPAR/HO-1 pathways. BCA may be an attractive drug for the prevention and treatment of atherosclerotic cardiovascular disease.
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http://dx.doi.org/10.1155/2020/8965047DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8074550PMC
May 2021

Activation of Carbon Dioxide by CoCD ( = 0-4) Anions.

J Phys Chem A 2021 May 25;125(17):3710-3717. Epub 2021 Apr 25.

State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.

Laser ablation generated CoCD ( = 0-4) anions were mass selected and then reacted with CO 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 CO into CO. In contrast, the bare Co anion is inert toward CO. Coordinated D ligands can modify the reactivity of CoCD in which CoCD can reduce CO into CO selectively and CoCD can only adsorb CO. The crucial roles of the coordinated C and D ligands to tune the reactivity of CoCD ( = 0-4) toward CO were rationalized by theoretical calculations. Note that the hydrogenation process that is usually observed in the reactions of gas-phase metal hydrides with CO is completely suppressed for the reactions CoCD + CO. This study provides insights into the molecular-level origin for the observations that CO can be selectively generated from CO catalyzed by cobalt-containing carbides in heterogeneous catalysis.
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http://dx.doi.org/10.1021/acs.jpca.1c02229DOI Listing
May 2021

CTRP12 ameliorates atherosclerosis by promoting cholesterol efflux and inhibiting inflammatory response via the miR-155-5p/LXRα pathway.

Cell Death Dis 2021 Mar 10;12(3):254. Epub 2021 Mar 10.

Institute of Clinical Medicine, The Second Affiliated Hospital of Hainan Medical University, Haikou, 570100, Hainan, China.

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.
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http://dx.doi.org/10.1038/s41419-021-03544-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7947013PMC
March 2021

LncRNA kcnq1ot1 promotes lipid accumulation and accelerates atherosclerosis via functioning as a ceRNA through the miR-452-3p/HDAC3/ABCA1 axis.

Cell Death Dis 2020 12 9;11(12):1043. Epub 2020 Dec 9.

Institute of Clinical Medicine, The Second Affiliated Hospital of Hainan Medical University, Haikou, 570100, Hainan, PR China.

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.
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http://dx.doi.org/10.1038/s41419-020-03263-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7723992PMC
December 2020

Catalytic CO Oxidation by O Mediated with Single Gold Atom Doped Titanium Oxide Cluster Anions AuTi O.

Chemphyschem 2020 11 28;21(22):2550-2556. Epub 2020 Oct 28.

State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.

Gas-phase studies on catalytic CO oxidation by O 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 O activation. Herein, we identified that CO oxidation by O can be catalyzed by the AuTi O clusters, among which AuTi O with closed-shell electronic structure can effectively activate O . The reactions were characterized by mass spectrometry and quantum chemical calculations. Theoretical calculations showed that in the initial stage of O activation, the Ti O moiety in AuTi O contributes dominantly to activate O into superoxide (O ⋅) without participation of the Au atom. In subsequent steps, the intimate charge transfer interaction between Au and the Ti O moiety drives the direct dissociation of the O ⋅ unit.
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http://dx.doi.org/10.1002/cphc.202000755DOI Listing
November 2020

Reactivity of Neutral Tantalum Sulfide Clusters TaS ( = 0-4) with N.

J Phys Chem A 2020 Sep 9;124(38):7749-7755. Epub 2020 Sep 9.

State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.

Nitrogen (N) 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 N has received considerable attention to gain fundamental insights into nitrogen fixation. Herein, neutral tantalum sulfide clusters have been prepared and their reactivity toward N has been investigated by mass spectrometry in conjunction with density functional theory (DFT) calculations. The experimental results showed that TaS ( = 0-3) could adsorb N, while TaS was inert to N The DFT calculations revealed that the complete cleavage of the N≡N bond on the trinuclear metal center in the TaS/N reaction systems was overall barrierless under thermal collision conditions. The sulfur ligands can facilitate the approaching of N toward the metal center but weaken the electron-donating ability of the metal center. The inertness of TaS is ascribed to the electron-deficient state of Ta in TaS and the least effective orbital interaction in the TaS/N couple. This study provides new insights into the ligand effect on the interaction of the metal clusters with N
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http://dx.doi.org/10.1021/acs.jpca.0c06462DOI Listing
September 2020

High glucose condition inhibits trophoblast proliferation, migration and invasion by downregulating placental growth factor expression.

J Obstet Gynaecol Res 2020 Sep 8;46(9):1690-1701. Epub 2020 Jun 8.

Institute of Cardiovascular Disease, Key Laboratory for Arteriosclerology of Hunan Province, Hunan International Scientific and Technological Cooperation Base of Arteriosclerotic Disease, Hengyang Medical College, University of South China, Hengyang, China.

Aim: This study aimed to investigate the effect of high glucose (HG) level on the proliferation, migration and invasion of trophoblasts and determine the role of placental growth factor (PLGF) in the process.

Methods: HTR8-S/Vneo was treated with different concentrations of d-glucose (0, 10, 15, 20, 25 and 30 μM) at different times (0, 6, 12 and 24 h). qRT-PCR and Western blot analyses were used to measure PLGF expression. The protein level of PLGF was measured by immunofluorescence. Cell proliferation was assessed with CCK-8 analysis. Wound healing and transwell assays were used to evaluate cell migration and invasion. Intercellular ROS was detected with DCFH-DA.

Results: After d-glucose treatment, the viability decreased in 25 and 30 μM groups. The HG group (25 μM) showed inhibited cell migration and invasion ability. The mRNA and protein levels of PLGF decreased under HG condition. Elevated ROS production was also detected in the HG group. Knocked-down PLGF expression enhanced increased ROS production and decreased cell migration and invasion, which reverted to the original levels after PLGF was overexpressed.

Conclusion: High glucose treatment inhibited HTR8-S/Vneo viability, migration and invasion by downregulating PLGF expression.
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http://dx.doi.org/10.1111/jog.14341DOI Listing
September 2020

A Facile N≡N Bond Cleavage by the Trinuclear Metal Center in Vanadium Carbide Cluster Anions VC.

J Am Chem Soc 2020 Jun 8;142(24):10747-10754. Epub 2020 Jun 8.

CAS Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.

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 N and subsequent C-N coupling on trinuclear carbide cluster anions VC 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 N bonded with the V 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 N 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 N. Furthermore, carbon ligands also play a considerable role in enhancing the reactivity of the metal core toward N. This study strongly suggests a new mechanism of N≡N bond cleavage by gas-phase metal clusters.
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http://dx.doi.org/10.1021/jacs.0c02021DOI Listing
June 2020

[Effect of low-frequency electrical acupoint stimulation on gastrointestinal motility function following radical gastrectomy in patients with gastric cancer].

Zhen Ci Yan Jiu 2020 Jan;45(1):51-6

Department of Rehabilitation, Shanghai Changhai Hospital, Shanghai 200433, China.

Objective: 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.

Methods: A total of 177 patients undergoing radical gastrectomy were randomly divided into conventional group (=43), low-frequency electrical acupoint stimulation (LEAS) group (=45), fast track surgery (FTS) group (=46) and FTS+LEAS group (=43). Patients of the conventional group received conventional treatment (pre-surgical mechanical bowel preparation, post-surgical fasting, and indwelling abdominal drainage tube, etc.). Patients in the LEAS group were treated by low-frequency electrical stimulation at bilateral Zusanli (ST36), Shangjuxu(ST37), Xiajuxu(ST39) and Sanyinjiao(SP6) for 30 min, once daily from 1 day after the operation to first postoperative flatus. FTS group was given fast track surgery treatment, such as preoperative education, preoperative nutritional support, early oral feeding, early removal of abdominal drainage tube, etc. The FTS+LEAS group was given low-frequency electrical acupoint stimulation on the basis of the FTS treatment. Levels of white blood cells (WBC), neutrophils (N), C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) at 1, 3, and 6 d after the operation in the 4 groups were assayed. The first postoperative flatus and defecation time were recorded.

Results: 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 (<0.05), and the first flatus time of the FTS+LEAS group was even earlier than that of the FTS group (<0.05). No significant differences were found among the 3 groups in the postoperative defecation time (>0.05). The CRP levels in the 4 groups on 3 and 6 d after operation were higher than those on the 1st postoperative day, and the highest level was on 3 d after the operation. Compared with the conventional group, CRP level on 3 d and CRP and IL-6 levels on 3 and 6 d in the LEAS and FTS+LEAS groups were significantly lower (<0.05). Compared with the LEAS group, the levels of N, CRP on 3 d and the levels of N, CRP, IL-6 on 6 d in the FTS group were significantly increased (<0.05). Compared with the FTS group, the level of CRP on 3 d and the levels of N, CRP, IL-6 on 6 d in the FTS+LEAS group were significantly decreased (<0.05).

Conclusion: 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.
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http://dx.doi.org/10.13702/j.1000-0607.1901256DOI Listing
January 2020

Inhibition of the ox-LDL-Induced Pyroptosis by FGF21 of Human Umbilical Vein Endothelial Cells Through the TET2-UQCRC1-ROS Pathway.

DNA Cell Biol 2020 Apr 26;39(4):661-670. Epub 2020 Feb 26.

Institute of Cardiovascular Disease, Key Laboratory for Arteriosclerology of Hunan Province, Hunan International Scientific and Technological Cooperation Base of Arteriosclerotic Disease, Hengyang Medical College, University of South China, Hengyang, Hunan, China.

Fibroblast growth factor 21 (FGF21) is a hormone-like member of the FGF family that is associated with cell death in atherosclerosis. However, its underlying mechanisms remain unclear. In this study, the effect of FGF21 on endothelial cell pyroptosis and its potential mechanisms were investigated. Results showed that FGF21 inhibits oxidized low-density lipoprotein (ox-LDL)-induced pyroptosis and related molecular expression in human umbilical vein endothelial cells (HUVECs). Mitochondrial function was damaged by ox-LDL and restored by FGF21. A mechanism proved that ubiquinol cytochrome c reductase core protein I (UQCRC1) was downregulated by ox-LDL and upregulated by FGF21. Further, the silencing of UQCRC1 aggravated HUVEC pyroptosis and impaired mitochondrial function and reactive oxygen species (ROS) production. Moreover, Tet methylcytosine dioxygenase (TET2) was involved in the regulation of UQCRC1 expression and pyroptosis. In summary, FGF21 inhibited ox-LDL-induced HUVEC pyroptosis through the TET2-UQCRC1-ROS pathway.
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http://dx.doi.org/10.1089/dna.2019.5151DOI Listing
April 2020

The 5-Lipoxygenase Inhibitor Zileuton Protects Pressure Overload-Induced Cardiac Remodeling via Activating PPAR.

Oxid Med Cell Longev 2019 3;2019:7536803. Epub 2019 Nov 3.

Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, China.

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 PPAR, but not PPAR or PPAR, thus inducing Keap and NRF2 activation. This was confirmed with the PPAR inhibitor GW7647 and NRF2 siRNA, which abolished the protective effects of zileuton on cardiomyocytes. Moreover, PPAR 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 PPAR/NRF2 signaling.
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http://dx.doi.org/10.1155/2019/7536803DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6874937PMC
April 2020

Infliximab therapy and outcomes in patients with polyarticular juvenile idiopathic arthritis: a single-center study in China.

World J Pediatr 2020 Feb 14;16(1):68-73. Epub 2019 Oct 14.

Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.

Background: 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.

Methods: 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.

Results: 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/ < 0.001, and 0.05/0.012/ < 0.001, respectively) and 6 months (P = 0.036/0.045/0.041, 0.076/0.037/ < 0.001, and 0.096/0.006/ < 0.001, respectively) of infliximab treatment, although the rates of change of these parameters were similar. However, after 12 months, only patients treated with infliximab within 3 months of disease onset had a stable ESR, active joint count, and JADAS-27, while these parameters increased sharply when infliximab was administered 3 months and especially 1 year after disease onset.

Conclusions: TNF-alpha is a pleiotropic pro-inflammatory cytokine of crucial importance in the pathogenesis of JIA. Infliximab can improve the outcomes of patients with pJIA significantly, and should be introduced early during the clinical course.
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http://dx.doi.org/10.1007/s12519-019-00316-5DOI Listing
February 2020

Neutral Au-Doped Cluster Catalysts AuTiO for CO Oxidation by O.

J Am Chem Soc 2019 Feb 14;141(5):2027-2034. Epub 2019 Jan 14.

State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , China.

Oxide supported gold catalysts (e.g., Au/TiO) are of great significance in heterogeneous catalysis owing to their extraordinary catalytic activity. Study of heteronuclear metal oxide clusters (HMOCs, e.g., Au Ti O ) 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 Au-doped titanium oxide clusters AuTiO in catalytic CO oxidation by O 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 O activation have been discovered in the cluster catalysis. The fascinating results are of substantial importance to understand the mechanisms of CO oxidation over Au/TiO, one type of the best studied gold catalysts.
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http://dx.doi.org/10.1021/jacs.8b11118DOI Listing
February 2019

Coupling of Methane and Carbon Dioxide Mediated by Diatomic Copper Boride Cations.

Angew Chem Int Ed Engl 2018 Oct 1;57(43):14134-14138. Epub 2018 Oct 1.

State Key Laboratory for Structural Chemistry of, Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.

The use of CH and CO 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 CH with CO under thermal collision conditions to produce ketene (H C=C=O), an important intermediate in synthetic chemistry. The order to feed the reactants (CH and CO ) is important and CH should be firstly fed to produce the C product. Molecular-level mechanisms including control of product selectivity have been revealed for coupling of CH with CO under mild conditions.
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http://dx.doi.org/10.1002/anie.201808780DOI Listing
October 2018

Mechanistic Variants in Methane Activation Mediated by Gold(I) Supported on Silicon Oxide Clusters.

Chemistry 2018 Nov 5;24(66):17506-17512. Epub 2018 Nov 5.

State Key Laboratory for Structural Chemistry, of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.

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 Au on silicon oxide cluster supports of variable sizes, the site-specific methane activation by Au -O 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(SiO ) 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 (Au ), which was anchored on an AuSiO or AuSi O cluster, through an oxidative addition mechanism (a homolytic process), and high efficiency was observed for the one-fold-coordinated gold ion (Au ), which was supported on an AuSi O cluster, through Lewis acid/base pairs mechanism (Au ⋅⋅⋅O , a heterolytic process). Fine regulation of the 5d orbital level of the Au atom by the oxygen ligands accounted for the mechanistic difference between Au and Au species. The mechanistic understanding of the reactivity of Au -O at a strictly molecular level can be used to clarify the dissimilar activity of gold anchored on different oxide supports.
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http://dx.doi.org/10.1002/chem.201803432DOI Listing
November 2018

Thermal activation of methane by vanadium boride cluster cations VB (n = 3-6).

Phys Chem Chem Phys 2018 Feb;20(7):4641-4645

State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.

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 VB (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 VB reaction system. Compared to the non-polar bare B cluster, the B moiety in VB 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.
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http://dx.doi.org/10.1039/c8cp00071aDOI Listing
February 2018

miR-23b-3p and miR-125b-5p downregulate apo(a) expression by targeting Ets1 in HepG2 cells.

Cell Biol Int 2018 Mar 15;42(3):313-323. Epub 2017 Nov 15.

Institute of Cardiovascular Research, Key Laboratory for Atherosclerology of Hunan Province, University of South China, Hengyang, Hunan, 421001, PR China.

High concentrations of plasma lipoprotein(a) [Lp(a)] have been inferred to be an independent risk factor for cardiovascular and cerebrovascular diseases, such as coronary artery diseases, restenosis, and stroke. Apolipoprotein(a) [apo(a)] is one of the most important components of Lp(a) and contributes greatly to the increased concentration of plasma Lp(a). As a critical positive transacting factor of apo(a) gene, Ets1 has been proven as a target gene of several miRNAs, such as miR-193b, miR-125b-5p, miR-200b, miR-1, and miR-499. In this study, a series of experiments on miRNAs and relative miRNAs inhibitor delivered HepG2 cells were conducted, and two miRNAs that downregulate the apo(a) by targeting the 3'-UTR of Ets1 were identified. Results showed that apo(a) and Ets1 were differentially expressed in SMMC7721 and HepG2 cell lines. Meanwhile, apo(a) and Ets1 were inversely correlated with several hepatic endogenous miRNAs, such as miR-125b-5p, miR-23b-3p, miR-26a-5p, and miR-423-5p, which were predicted to bind to Ets1. Results show that miR-125b-5p and miR-23b-3p mimics could inhibit the synthesis of apo(a) by directly targeting Ets1 in HepG2, thereby reducing the plasma Lp (a) concentration.
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http://dx.doi.org/10.1002/cbin.10896DOI Listing
March 2018

Size-Dependent Reactivity of Nano-Sized Neutral Manganese Oxide Clusters toward Ethylene.

Chemistry 2017 Nov 17;23(62):15820-15826. Epub 2017 Oct 17.

State Key Laboratory for Structural Chemistry of Unstable and Stable Species, CAS Research/Education Center of Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P.R. China.

Neutral manganese oxide clusters with the general composition Mn O (N=2-22; x=-1, 0, 1) with dimensions up to a nanosize were prepared by laser ablation and reacted with C H in a fast flow reactor. The size-dependent reactivity of C H adsorption on these clusters was experimentally identified and the adsorption reactivity decreases generally with an increase of the cluster size. Density functional theory calculations were performed to study the geometrical and electronic structures of the Mn O (N=1-6) clusters. The calculated results indicated that the coordination number and the charge distribution of the metal centers are responsible for the experimentally observed size-dependent reactivity. The highly charged Mn atoms with low coordination are preferential to adsorb C H . In contrast, the neutral manganese oxide clusters are completely inert toward the saturated hydrocarbon molecule C H . This work provides new perspectives to design related materials in the separation of hydrocarbon molecules.
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http://dx.doi.org/10.1002/chem.201703745DOI Listing
November 2017

Molecular signal networks and regulating mechanisms of the unfolded protein response.

J Zhejiang Univ Sci B 2017 Jan.;18(1):1-14

Institute of Aging Research, School of Medicine, Hangzhou Normal University, Hangzhou 310036, China.

Within the cell, several mechanisms exist to maintain homeostasis of the endoplasmic reticulum (ER). One of the primary mechanisms is the unfolded protein response (UPR). In this review, we primarily focus on the latest signal webs and regulation mechanisms of the UPR. The relationships among ER stress, apoptosis, and cancer are also discussed. Under the normal state, binding immunoglobulin protein (BiP) interacts with the three sensors (protein kinase RNA-like ER kinase (PERK), activating transcription factor 6 (ATF6), and inositol-requiring enzyme 1α (IRE1α)). Under ER stress, misfolded proteins interact with BiP, resulting in the release of BiP from the sensors. Subsequently, the three sensors dimerize and autophosphorylate to promote the signal cascades of ER stress. ER stress includes a series of positive and negative feedback signals, such as those regulating the stabilization of the sensors/BiP complex, activating and inactivating the sensors by autophosphorylation and dephosphorylation, activating specific transcription factors to enable selective transcription, and augmenting the ability to refold and export. Apart from the three basic pathways, vascular endothelial growth factor (VEGF)-VEGF receptor (VEGFR)-phospholipase C-γ (PLCγ)-mammalian target of rapamycin complex 1 (mTORC1) pathway, induced only in solid tumors, can also activate ATF6 and PERK signal cascades, and IRE1α also can be activated by activated RAC-alpha serine/threonine-protein kinase (AKT). A moderate UPR functions as a pro-survival signal to return the cell to its state of homeostasis. However, persistent ER stress will induce cells to undergo apoptosis in response to increasing reactive oxygen species (ROS), Ca in the cytoplasmic matrix, and other apoptosis signal cascades, such as c-Jun N-terminal kinase (JNK), signal transducer and activator of transcription 3 (STAT3), and P38, when cellular damage exceeds the capacity of this adaptive response.
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http://dx.doi.org/10.1631/jzus.B1600043DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5260473PMC
July 2017

Differential impact of affective and cognitive attributes on preference under deliberation and distraction.

Front Psychol 2015 30;6:549. Epub 2015 Apr 30.

Department of Advertising, Xiamen University Xiamen, China.

Two experiments were designed to test the hypothesis that affective information looms relatively larger than cognitive information when individuals are distracted for a period of time compared to when they engage in deliberative thinking. In two studies, participants were presented with information about 4 decision alternatives: An affective alternative that scored high on affective attributes but low on cognitive attributes, a cognitive alternative with the opposite trade-off, and two fillers. They were then asked to indicate their attitudes toward each of four decision alternatives either immediately, after a period of deliberation, or after a period of distraction. The results of both experiments demonstrated that participants significantly preferred the affective alternative to the cognitive alternative after distraction, but not after deliberation. The implications for understanding when and how unconscious thought may lead to better decisions are being discussed.
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http://dx.doi.org/10.3389/fpsyg.2015.00549DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4415306PMC
May 2015

High-density genetic linkage map construction and QTL mapping of grain shape and size in the wheat population Yanda1817 × Beinong6.

PLoS One 2015 12;10(2):e0118144. Epub 2015 Feb 12.

State Key Laboratory for Agrobiotechnology / Department of Plant Genetics & Breeding, China Agricultural University, Beijing 100193, China.

High-density genetic linkage maps are necessary for precisely mapping quantitative trait loci (QTLs) controlling grain shape and size in wheat. By applying the Infinium iSelect 9K SNP assay, we have constructed a high-density genetic linkage map with 269 F 8 recombinant inbred lines (RILs) developed between a Chinese cornerstone wheat breeding parental line Yanda1817 and a high-yielding line Beinong6. The map contains 2431 SNPs and 128 SSR & EST-SSR markers in a total coverage of 3213.2 cM with an average interval of 1.26 cM per marker. Eighty-eight QTLs for thousand-grain weight (TGW), grain length (GL), grain width (GW) and grain thickness (GT) were detected in nine ecological environments (Beijing, Shijiazhuang and Kaifeng) during five years between 2010-2014 by inclusive composite interval mapping (ICIM) (LOD ≥ 2.5). Among which, 17 QTLs for TGW were mapped on chromosomes 1A, 1B, 2A, 2B, 3A, 3B, 3D, 4A, 4D, 5A, 5B and 6B with phenotypic variations ranging from 2.62% to 12.08%. Four stable QTLs for TGW could be detected in five and seven environments, respectively. Thirty-two QTLs for GL were mapped on chromosomes 1B, 1D, 2A, 2B, 2D, 3B, 3D, 4A, 4B, 4D, 5A, 5B, 6B, 7A and 7B, with phenotypic variations ranging from 2.62% to 44.39%. QGl.cau-2A.2 can be detected in all the environments with the largest phenotypic variations, indicating that it is a major and stable QTL. For GW, 12 QTLs were identified with phenotypic variations range from 3.69% to 12.30%. We found 27 QTLs for GT with phenotypic variations ranged from 2.55% to 36.42%. In particular, QTL QGt.cau-5A.1 with phenotypic variations of 6.82-23.59% was detected in all the nine environments. Moreover, pleiotropic effects were detected for several QTL loci responsible for grain shape and size that could serve as target regions for fine mapping and marker assisted selection in wheat breeding programs.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0118144PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4326355PMC
November 2015

[Identification of two Fusarium isolates and their crude toxin allelopathic effect on Cucumis melo seedlings].

Ying Yong Sheng Tai Xue Bao 2013 Jan;24(1):142-8

College of Life Sciences, Northwest A&F University, Yangling 712100, Shaanxi, China.

Eight fungi isolates were obtained from Fusarium-infected Cucumis melo (melon) plants and their rhizosphere soils. Taking melon cultivar 'Xitian 1' as test material, the re-inoculation and seed germination experiments were conducted to investigate the pathogenicity and growth inhibition effect of these fungi isolates on melon. Through the determination of the induced enzyme activities, resistant substance contents, and cell membrane permeability of potted melon roots, the allelopathic effect of the crude toxins of two harmful fungi was studied, and according to the morphological characteristics and Internal Transcribed Spacer (ITS) sequencing, the two harmful fungi were identified. The crude toxins of the two harmful fungi TF and HF had strong inhibition effects on the germination and growth of the melon seeds. The MDA and soluble protein contents and the cell membrane permeability of the 'Xitian 1' seedlings roots all increased, among which, the MDA content and cell membrane permeability increased by 108.6% and 40.6%, respectively when treated with the stock solution of TF toxin, compared with the control. The crude toxins of the two harmful fungi improved the induced enzyme activities of the melon roots, with the increment of the PAL and POD activities under the treatment of 10-fold dilution of TF crude toxin increased by 25.6% and 23.2%, respectively. When treated with the stock solution of HF toxin, the PAL activity significantly increased by 30.0%. The two harmful fungi TF and HF were primarily identified as Fusarium equisti and F. proliferatum, respectively. This study showed that the two Fusarium isolates could not infect melon via re-inoculation, but could negatively affect the melon's normal growth and normal physiological and biochemical metabolism via toxins excretion, and in the meantime, improve the root protective enzyme activities, with the effects of both benefit and harmfulness on melon plants. The allelopathic hazard of the crude toxins of the isolates could be one of the main causes of continuous cropping obstacle of melon.
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January 2013

The roles of the proteasome pathway in signal transduction and neurodegenerative diseases.

Neurosci Bull 2008 Jun;24(3):183-94

Department of Pharmacology and Laboratory of Aging and Nervous Diseases, Soochow University School of Medicine, Suzhou, China.

There are two degradation systems in mammalian cells, autophagy/lysosomal pathway and ubiquitin-proteasome pathway. Proteasome is consist of multiple protein subunits and plays important roles in degradation of short-lived cellular proteins. Recent studies reveal that proteasomal degradation system is also involved in signal transduction and regulation of various cellular functions. Dysfunction or dysregulation of proteasomal function may thus be an important pathogenic mechanism in certain neurological disorders. This paper reviews the biological functions of proteasome in signal transduction and its potential roles in neurodegenerative diseases.
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http://dx.doi.org/10.1007/s12264-008-0183-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5552546PMC
June 2008