Histological Validation of Cardiovascular Magnetic Resonance T1 Mapping for Assessing the Evolution of Myocardial Injury in Myocardial Infarction: An Experimental Study

Zhang Lu,Yang Zhi-gang,Xu Huayan,Yang Meng-xi,Xu Rong,Chen Lin,Sun Ran,Miao Tianyu,Zhao Jichun,Zhou Xiaoyue,Fu Chuan,Guo Yingkun 대한영상의학회 2020 Korean Journal of Radiology Vol.21 No.12

Objective: To determine whether T1 mapping could monitor the dynamic changes of injury in myocardial infarction (MI) and be histologically validated. Materials and Methods: In 22 pigs, MI was induced by ligating the left anterior descending artery and they underwent serial cardiovascular magnetic resonance examinations with modified Look-Locker inversion T1 mapping and extracellular volume (ECV) computation in acute (within 24 hours, n = 22), subacute (7 days, n = 13), and chronic (3 months, n = 7) phases of MI. Masson’s trichrome staining was performed for histological ECV calculation. Myocardial native T1 and ECV were obtained by region of interest measurement in infarcted, peri-infarct, and remote myocardium. Results: Native T1 and ECV in peri-infarct myocardium differed from remote myocardium in acute (1181 ± 62 ms vs. 1113 ± 64 ms, p = 0.002; 24 ± 4% vs. 19 ± 4%, p = 0.031) and subacute phases (1264 ± 41 ms vs. 1171 ± 56 ms, p < 0.001; 27 ± 4% vs. 22 ± 2%, p = 0.009) but not in chronic phase (1157 ± 57 ms vs. 1120 ± 54 ms, p = 0.934; 23 ± 2% vs. 20 ± 1%, p = 0.109). From acute to chronic MI, infarcted native T1 peaked in subacute phase (1275 ± 63 ms vs. 1637 ± 123 ms vs. 1471 ± 98 ms, p < 0.001), while ECV progressively increased with time (35 ± 7% vs. 46 ± 6% vs. 52 ± 4%, p < 0.001). Native T1 correlated well with histological findings (R2 = 0.65 to 0.89, all p < 0.001) so did ECV (R2 = 0.73 to 0.94, all p < 0.001). Conclusion: T1 mapping allows the quantitative assessment of injury in MI and the noninvasive monitoring of tissue injury evolution, which correlates well with histological findings.

G Protein–Coupled Receptor 30 Mediates the Anticancer Effects Induced by Eicosapentaenoic Acid in Ovarian Cancer Cells

Yue Zhao,Meng-Fei Zhao,Mei-Lin Yang,Tian-Yu Wu,Cong-Jian Xu,Jing-Mei Wang,Chao-Jun Li,Xi Li 대한암학회 2020 Cancer Research and Treatment Vol.52 No.3

Purpose: While numerous epidemiological studies have indicated that omega-3 polyunsaturated fatty acids have anticancer properties in various cancers, the effects and mechanisms of eicosapentaenoic acid (EPA) in ovarian cancer cell growth are poorly understood. Materials and Methods: ES2 ovarian clear cell carcinoma cells and SKOV3 adenocarcinoma cells were treated with palmitic acid or EPA, followed by flow cytometry and cell counting to measure apoptosis and proliferation, respectively. A modified protein lipid overlay assay was used to further verify whether EPA was a ligand of G protein–coupled receptor 30 (GPR30) in ES2 cells. The levels of apoptosis-related genes, phosphorylated AKT, and phosphorylated ERK1/2 were detected to explore the underlying mechanism. Finally, inhibitory effect of EPA on tumor growth via GPR30 was determined in vitro and in vivo. Results: EPA suppressed ES2 ovarian clear cell carcinoma cells growth via GPR30, a novel EPA receptor, by inducing apoptosis. As a ligand of GPR30, EPA activated the GPR30-cAMP– protein kinase A signaling pathway. When GPR30 was suppressed by siRNA or its inhibitor G15, the antiproliferative action of EPA was impaired. Furthermore, EPA inhibited tumor growth by blocking the activation of AKT and ERK. In the mouse xenograft model, EPA decreased tumor volume and weight through GPR30 by blocking tumor cell proliferation. Conclusion: These results confirm that EPA is a tumor suppressor in human ovarian clear cell carcinoma cells and functions through a novel fatty acid receptor, GPR30, indicating a mechanistic linkage between omega-3 fatty acids and cancers.

Lack of Effects of HER-2/neu on Prognosis in Colorectal Cancer: a Meta-analysis

Han, Jun,Meng, Qing-Yang,Liu, Xiao,Xi, Qiu-Lei,Zhuang, Qiu-Lin,Wu, Guo-Hao Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.14

Background: The prognostic value of human epidermal growth factor receptor-2 (HER-2/neu) for survival of patients with colorectal cancer (CRC) is still ambiguous. We therefore performed a meta-analysis to evaluate its prognostic significance. Materials and Methods: We searched the MEDLINE and EMBASE databases for published literature investigating associations between HER-2/neu status and overall survival of patients with CRC. A meta-analysis was performed using a DerSimonian-Laird model and publication bias was investigated by Begg's and Egger's tests. Subgroup analysis was also conducted according to the study design type, study quality score, cut-off value for HER-2/neu overexpression, publication region, patient number and publication year. Results: A total of 17 eligible studies involving 2,347 patients were identified for this meta-analysis. The combined hazard ratio (HR) was 1.31 (95% confidence interval (CI): 0.96-1.79), suggesting that HER-2/neu overexpression was not significantly associated with overall survival of patients with CRC. However, subgroup analysis revealed that HER-2/neu overexpression had an unfavorable impact on survival when the analysis was restricted to subgroups of study quality score ${\leq}5 $(HR=1.56, 95%CI: 1.17-2.10), Asian patients (HR=1.74, 95%CI: 1.22-2.49), patient number ${\leq}106$ (HR=1.57, 95%CI: 1.01-2.44), publication year before 2003 (HR=1.59, 95%CI: 1.02-2.49), and prospectively designed study (HR=3.62, 95%CI: 1.42-9.24). The effect disappeared in subgroups of study quality scores > 5 (HR=0.69, 95%CI: 0.33-1.44), non Asian patients (HR=1.14, 95%CI: 0.77-1.70), patients' number > 106 (HR=1.07, 95%CI: 0.67-1.72), publication year after 2003 (HR=1.13, 95%CI: 0.76-1.69), and retrospectively designed study (HR=1.22, 95%CI: 0.89-1.67). Conclusions: Our meta-analysis suggests that HER-2/neu overexpression might not be a significantly prognostic indicator for patients with CRC. Further studies are required to confirm these results.

Synthesis, Antibacterial Activity, and Structure–Activity Relationship of Fusaric Acid Analogs

Qing-Yan Zhang,Yang Fei‐Yu,Liao Shang‐Gao,Wang Bing,Li Rui,Dong Yong‐Xi,Zhou Meng,Yang Yuan‐Yong,Xu Guo‐Bo 대한화학회 2021 Bulletin of the Korean Chemical Society Vol.42 No.4

Forty-one fusaric acid analogs possessing a pyridine carboxylic acid scaffold have been synthesized. The antibacterial activity results demonstrated that compounds 5b, 7b, 8c, and 8d displayed strong antibacterial activities against Staphylococcus aureus ATCC25923 with minimum inhibitory concentrations (MICs) of 4–16 μg/mL. Molecular docking study indicated that these compounds have strong hydrogen-bonding interactions with TyrRS. Meanwhile, 8c and 8d showed promising antibacterial activities against Pseudomonas aeruginosa ATCC9027. Compound 4 exhibited pronounced antibacterial activities against a clinically isolated multidrug-resistant strain of Escherichia coli (MIC: 64 μg/mL as compared 64 μg/mL of levofloxacin and 1024 μg/mL of ceftriaxone sodium). Moreover, compound 17e displayed strong synergistic antibacterial effect with levofloxacin against the multidrug-resistant strain, decreasing the MIC value of levofloxacin to 1/16 of its original MIC. No obvious cytotoxic activities against LO2 was observed for compounds 4, 5b, 8c, 8d, 17d, and 17e at 50 μM. The preliminary structure–activity relationship of fusaric acid analogs was also discussed.

Enhanced electrochemical performance of Ca-doped NdBa_1-xCa_xCoCuO_5+δ as cathode material for intermediate-temperature solid oxide fuel cells

Pang, Shengli,Su, Yanjing,Yang, Gongmei,Shen, Xiangqian,Zhu, Meng,Wu, Xiao,Li, Songwei,Yang, Xiaofen,Xi, Xiaoming Elsevier 2018 Ceramics international Vol.44 No.17

<P><B>Abstract</B></P> <P>Exploring advanced cathode materials that have high electrochemical activity and superior thermal compatibility with other components is of great importance for the application of intermediate-temperature solid oxide fuel cells. In the present study, influences of Ca doping on electrochemical and physicochemical properties of NdBa<SUB>1-x</SUB>Ca<SUB>x</SUB>CoCuO<SUB>5+δ</SUB> were studied systematically. A relatively low thermal expansion coefficient (16.8 × 10<SUP>−6</SUP> °C<SUP>−1</SUP>) was obtained for the Ca-doped sample over the temperature range of 25–800 °C. Moreover, Ca doping significantly enhanced the electrochemical performance of NdBa<SUB>1-x</SUB>Ca<SUB>x</SUB>CoCuO<SUB>5+δ</SUB>. The highest densities of power for NdBa<SUB>1-x</SUB>Ca<SUB>x</SUB>CoCuO<SUB>5+δ</SUB>-based single cells at the temperatures of 800 °C increased from 1.42 W cm<SUP>−2</SUP> for x = 0.0 to 1.84 W cm<SUP>−2</SUP> for x = 0.3. This increase in electrochemical performance of NdBa<SUB>1-x</SUB>Ca<SUB>x</SUB>CoCuO<SUB>5+δ</SUB> cathode with Ca doping can be ascribed to enhanced concentrations of oxygen vacancies and higher electrical conductivity.</P>

Nanosheets of copolymerized ionic liquid-based polyelectrolyte complexes regulated at oil–water interface and their emulsification capability

He Zhang,Jun Bo Zhang,Qing Bo Meng,Wei Guo,Ming Yang,Shuyao Wu,Qiong Wu,Daliang Liu,Xi-Ming Song 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.97 No.-

The emulsification by polyelectrolyte complexes is easy to handle, and could be considered as an effectivestrategy for introducing functional materials to liquid–liquid interfaces, but the related studies are stillinsufficient. Herein, a kind of copolymerized ionic liquid (PIL-co-PVIm) which is synthesized from 1-vinyl-3-ethylimidazolium bromide and 1-vinylimidazole, are used as polycation to form polyelectrolytecomplexes type Pickering emulsifiers with sodium alginate, poly(sodium 4-styrenesulfonate) and poly(acrylic acid) sodium salt respectively as polyanion. For toluene-water emulsion systems andhydrophobic ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIm]PF6)-watersystem, the polyelectrolyte complexes formed by PIL-co-PVIm and sodium alginate or poly (sodium4-styrenesulfonate) showed best emulsification capability. The emulsions stabilized by the polyelectro-lyte complexes at stoichiometric ratio are relatively less stable compared to non-stoichiometriccomplexes, while PIL-co-PVIm without complexation has no emulsification capability. The polyelectro-lyte complexes based on homopolymerized PIL give an unsatisfied emulsification capability, while theemulsification performance could be remarkably improved by copolymerizing ionic liquids with theuncharged comonomer, but excessive contents of the uncharged unit make the polyelectrolytecomplexes less interface active. The sheet-like PECs are formed in aqueous dispersions, and theirthickness is remarkably reduced at oil–water interface after emulsification, approximately ranging from200 nm to 10 nm by manipulating the polyanion.

Molecular and Biochemical Characterization of a Novel Xylanase from Massilia sp. RBM26 Isolated from the Feces of Rhinopithecus bieti

( Bo Xu ),( Li Ming Dai ),( Jun Jun Li ),( Meng Deng ),( Hua Biao Miao ),( Jun Pei Zhou ),( Yue Lin Mu ),( Qian Wu ),( Xiang Hua Tang ),( Yun Juan Yang ),( Jun Mei Ding ),( Nan Yu Han ),( Zun Xi Huang 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.1

Xylanases sourced from different bacteria have significantly different enzymatic properties. Therefore, studying xylanases from different bacteria is important to their applications in different fields. A potential xylanase degradation gene in Massilia was recently discovered through genomic sequencing. However, its xylanase activity remains unexplored. This paper is the first to report a xylanase (XynRBM26) belonging to the glycosyl hydrolase family (GH10) from the genus Massilia. The gene encodes a 383-residue polypeptide (XynRBM26) with the highest identity of 62% with the endoxylanase from uncultured bacterium BLR13. The XynRBM26 expressed in Escherichia coli BL21 is a monomer with a molecular mass of 45.0 kDa. According to enzymatic characteristic analysis, pH 5.5 is the most appropriate for XynRBM26, which could maintain more than 90% activity between pH 5.0 and 8.0. Moreover, XynRBM26 is stable at 37°C and could maintain at least 96% activity after being placed at 37°C for 1 h. This paper is the first to report that GH10 xylanase in an animal gastrointestinal tract (GIT) has salt tolerance, which could maintain 86% activity in 5 M NaCl. Under the optimum conditions, Km, Vmax, and kcat of XynRBM26 to beechwood xylan are 9.49 mg/ml, 65.79 μmol/min/mg, and 47.34 /sec, respectively. Considering that XynRBM26 comes from an animal GIT, this xylanase has potential application in feedstuff. Moreover, XynRBM26 is applicable to high-salt food and seafood processing, as well as other high-salt environmental biotechnological fields, because of its high catalytic activity in high-concentration NaCl.

Effects of L-malic acid on alpha-glucosidase: inhibition kinetics and computational molecular dynamics simulations.

Gou, Lin,Zhan, Yi,Lee, Jinhyuk,Li, Xuan,Lü,, Zhi-Rong,Zhou, Hai-Meng,Lu, Hang,Wang, Xi-Yao,Park, Yong-Doo,Yang, Jun-Mo Humana Press 2015 Applied biochemistry and biotechnology Vol.175 No.4

<P>The inhibitory effect of L-malic acid (MA) on alpha-glucosidase (EC 3.2.1.20) was investigated by combination study between inhibition kinetics and computational simulations. The results from the serial kinetics demonstrated that MA could directly inactivate the enzyme activity in a dose-dependent manner and a typical non-competitive type, as well as in a fast inactivate process without detectable time course. The tertiary conformation study with an application of spectrofluorimetry showed that MA modulated the tertiary structural conformation of alpha-glucosidase both on the overall and on regional active site pocket, which monitored by red-shift intrinsic fluorescence peak with decreases intensities, and the significant intensity increasing of 1-anilinonaphthalene-8-sulfonate (ANS)-binding fluorescence, respectively. To have more insight, we also adapted the computational molecular dynamics (MD) simulations. The results showed that MA was located in the entrance of active pocket for the catalytic reaction and blocked the passage of substrate. It confirmed that MA inhibits as a non-competitive type, not direct docking to the glucose binding site. Our study provides important molecular mechanisms to figure out alpha-glucosidase inhibition that might associate to development of type 2 diabetes mellitus drug.</P>