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Tetramic acid-motif natural products from a marine fungus Tolypocladium cylindrosporum FB06 and their anti-Parkinson activities

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Marine Life Science & Technology 2024年第1期6卷 84-92页

作者： Yuna Jung Chaesun Kwon Taeyeon Kim Jin Woo Lee min-Kyoo shin Sang hee shim Natural Products Research Institute College of PharmacySeoul National UniversitySeoul 08826Republic of Korea College of Pharmacy and Research Institute of Pharmaceutical Sciences Seoul National UniversitySeoul 08826Republic of Korea College of Pharmacy Duksung Women’s UniversitySeoul 01369Republic of Korea

Tetramic acid-containing natural products are attracting significantly increasing attention from biologists and chemists due to their intriguing structures and biological *** the present study,two new tetramic acid alkaloids tolypyridone I(1)and tolypyridone J(2),together with five known ones(3–7),were isolated from cultures of a marine fungus Tolypocladium cylindrosporum FB06 isolate obtained from a marine sediment in Beaufort sea of North *** structures were elucidated using 1D,2D NMR,and *** configurations were established on the basis of 1h coupling constants,ROESY correlations and DP4 *** 2 was isolated as mixtures of rotational isomers with C-3 to C-7 axis between 4-hydroxy-2-pyridone and 1-ethyl-3,5-dimethylcyclohexane,hindering *** our unbiased screening to discover neuroprotective compounds in an in vitro Parkinson’s disease(PD)model,sh-SY5Y dopaminergic cells were treated with isolated compounds followed by treatment with 1-methyl-4-phenylpyridinium(MPP^(+)),a parkinsonian *** tested compounds,F-14329(7)significantly protected cells from MPP^(+)-induced ***^(+)-mediated cell death is known to be related to the regulation of Bcl-2 family proteins,specifically the down-regulation of anti-apoptotic Bcl-2 and the up-regulation of pro-apoptotic Bax *** with 2 mmol/L of MPP^(+)for 24 h significantly reduced Bcl-2 levels compared to control treated with ***,treatment with F-14329(7)attenuated such *** study demonstrates that tetramic acid-motif compounds could be potential lead compounds for treating PD.

关键词： Tolypocladium cylindrosporum Tetramic acid Tolypyridone Parkinson’s disease

甲基化转移酶WTAP调节转录激活因子4表达加剧缺氧/复氧诱导的心肌细胞损伤

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中华危重病急救医学 2024年第3期36卷 279-285页

作者：杨娜曹敏成都市第三人民医院麻醉科四川成都610000 成都市第三人民医院泌尿外科四川成都610000

目的观察甲基化转移酶Wilms肿瘤蛋白1相关蛋白(WTAP)在缺氧/复氧(h/R)诱导的心肌细胞损伤中的调节作用及其分子机制。方法①实验一:将h9C2心肌细胞分为空白对照组和h/R模型组。采用h/R诱导h9C2细胞建立心肌缺血/再灌注(I/R)损伤模型;空... 详细信息

目的观察甲基化转移酶Wilms肿瘤蛋白1相关蛋白(WTAP)在缺氧/复氧(h/R)诱导的心肌细胞损伤中的调节作用及其分子机制。方法①实验一:将h9C2心肌细胞分为空白对照组和h/R模型组。采用h/R诱导h9C2细胞建立心肌缺血/再灌注(I/R)损伤模型;空白对照组不进行处理。采用N6-甲基腺苷(m6A)RNA甲基化测定试剂盒检测m6A水平;分别采用实时荧光定量聚合酶链反应(RT-qPCR)和蛋白质免疫印迹试验(Western blotting)检测甲基化转移酶〔WTAP、甲基转移酶样蛋白(METTL3、METTL14)〕的基因和蛋白表达水平。②实验二:将h9C2心肌细胞分为空白对照组、h/R+sh-NC组、h/R+sh-WTAP组。h/R+sh-WTAP组转染sh-WTAP以敲降WTAP表达,其余各组制模方法同实验一。转染48 h后,采用流式细胞术检测细胞凋亡率;采用Western blotting检测WTAP、活化天冬氨酸特异性半胱氨酸蛋白酶3(caspase-3)、活化多聚二磷酸腺苷酸核糖聚合酶(PARP)、转录激活因子4(ATF4)、蛋白激酶RNA样内质网激酶(PERK)、磷酸化PERK(p-PERK)和CCAAT/增强子结合蛋白同源蛋白(ChOP)的蛋白表达水平;采用免疫荧光染色观察ATF4阳性表达情况。③实验三:将h9C2心肌细胞分为空白对照组、h/R+sh-NC组、h/R+sh-WTAP和h/R+sh-WTAP+ATF4组。h/R+sh-WTAP+ATF4组用过表达质粒ATF4转染h9C2心肌细胞,其余各组制模方法同实验二。采用流式细胞术检测细胞凋亡率;采用Western blotting检测ATF4、ChOP、活化caspase-3和活化PARP的蛋白表达水平。结果①实验一:h/R模型组m6A甲基化水平较空白对照组显著上调。RT-qPCR检测结果显示,h/R模型组METTL3、METTL14和WTAP基因表达水平均较空白对照组显著上调,以WTAP上调最显著;Western blotting检测结果呈相同趋势。提示甲基化转移酶WTAP的表达水平在h/R诱导的心肌细胞中显著上调。②实验二:h/R+sh-WTAP组细胞凋亡水平较h/R+sh-NC组明显减少〔(14.16±1.58)%比(24.51±2.38)%,Ph/R+sh-WTAP组WTAP、活化caspase-3、活化PARP、p-PERK、ATF4和ChOP的蛋白表达水平均较h/R+sh-NC组显著下调。荧光显微镜下显示,h/R+sh-WTAP组ATF4阳性信号较h/R+sh-NC组显著减弱〔(19.36±1.81)%比(32.83±2.69)%,Ph/R诱导的心肌细胞凋亡和内质网应激。③实验三:h/R+sh-WTAP+ATF4组细胞凋亡水平较h/R+sh-WTAP组显著增加〔(26.61±2.76)%比(17.14±0.87)%,Ph/R+sh-WTAP+ATF4组ATF4、ChOP、活化caspase-3和活化PARP的蛋白表达水平较h/R+sh-WTAP组显著上调。提示过表达ATF4可逆转sh-WTAP对h/R诱导的心肌细胞中内质网应激和细胞凋亡的抑制作用。结论甲基化转移酶WTAP可调节ATF4表达,介导细胞凋亡和内质网应激,促进h/R诱导的心肌细胞损伤。

关键词：甲基转移酶 Wilms肿瘤蛋白1相关蛋白细胞凋亡内质网应激缺氧/复氧

Effects of Silicon Content and Intercritical Annealing on Manganese Partitioning in Dual Phase Steels

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Journal of Iron and Steel Research International 2010年第5期17卷 44-50页

作者： A Nouri h Saghafian sh Kheirandish Department of Metallurgy and Materials Engineering Iran University of Science and Technology

Steels of constant manganese and carbon contents with silicon content of 0.34 %- 2.26% were cast. The as-cast steels were then hot rolled at 1 100 ℃ in five passes to reduce the cast ingot thickness from 80 to 4 mm, air cooled to room temperature and cold rolled to 2 mm in thickness. Dual phase microstructures with different volume fraction of martensite were obtained through the intercritical annealing of the steels at different temperatures for 15 min followed by water quenching. In addition to intercritical annealing temperature, silicon content also altered the volume fraction of martensite in dual phase steels. The partitioning of manganese in dual phase silicon steels was investigated using energy-dispersive spectrometer （EDS）. The partitioning coefficient, defined as the ratio of the amounts of alloying element in the austenite to that in the adjacent ferrite, for manganese increased with increasing intercritieal annealing temperature and silicon content of steels. It was also found that the solubility of manganese in ferrite and austenite decreased with increasing intereritical temperature. The results were discussed by the diffusivity and the solubility of manganese in ferrite and austenite existed in dual phase silicon steels.

关键词： partitioning dual phase steel intercritical annealing temperature silicon manganese

Prediction of yttrium, lanthanum, cerium, and neodymium leaching recovery from apatite concentrate using artificial neural networks

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Journal of University of Science and Technology Beijing 2008年第4期15卷 367-374页

作者： E. Jorjani A.h. Bagherieh sh. Mesroghli S. Chehreh Chelgani Department of mining Engineering Research and Science Campus Islamic Azad University Poonak Hesarak Tehran Iran

The assay and recovery of rare earth elements （REEs） in the leaching process is being determined using expensive analytical methods： inductively coupled plasma atomic emission spectroscopy （ICP-AES） and inductively coupled plasma mass spectroscopy （ICP-MS）. A neural network model to predict the effects of operational variables on the lanthanum, cerium, yttrium, and neodymium recovery in the leaching of apatite concentrate is presented in this article. The effects of leaching time （10 to 40 min）, pulp densities （30% to 50%）, acid concentrations （20% to 60%）, and agitation rates （100 to 200 r/min）, were investigated and optimized on the recovery of REEs in the laboratory at a leaching temperature of 60℃. The obtained data in the laboratory optimization process were used for training and testing the neural network. The feed-forward artificial neural network with a 4-5-5-1 arrangement was capable of estimating the leaching recovery of REEs. The neural network predicted values were in good agreement with the experimental results. The correlations of R=l in training stages, and R=0.971, 0.952, 0.985, and 0.98 in testing stages were a result of Ce, Nd, La, and Y recovery prediction respectively, and these values were usually acceptable. It was shown that the proposed neural network model accurately reproduced all the effects of the operation variables, and could be used in the simulation of a leaching plant for REEs.

关键词： apatite neural networks rare earth elements leaching recovery

miR-15b-5p通过下调BDNF/TrkB/PSD95表达参与PD中抑郁样行为发生

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中华神经医学杂志 2024年第7期23卷 649-658页

作者：罗汉将吴城荔朱金勇陈敏桂林医学院附属医院神经科学实验室广西神经系统疾病临床医学研究中心广西脑与认知神经科学重点实验室桂林541001

目的探讨miR-15b-5p参与PD中抑郁样行为发生的机制。方法(1)将18只C57BL/6N小鼠按随机数字表法分为PD组、干预组及对照组,每组6只。PD组小鼠通过脑立体定位仪将0.25 mg/kg鱼藤酮注射至右侧纹状体以制备PD模型,干预组小鼠接受0.25 mg/kg... 详细信息

目的探讨miR-15b-5p参与PD中抑郁样行为发生的机制。方法(1)将18只C57BL/6N小鼠按随机数字表法分为PD组、干预组及对照组,每组6只。PD组小鼠通过脑立体定位仪将0.25 mg/kg鱼藤酮注射至右侧纹状体以制备PD模型,干预组小鼠接受0.25 mg/kg鱼藤酮及miR-15b-5p抑制物慢病毒注射,对照组小鼠注射等体积PBS。4周后进行旷场实验及转棒实验评价小鼠的运动能力,进行糖水偏好实验及强迫游泳实验评价小鼠的抑郁样行为表现,然后提取小鼠黑质及纹状体中相关蛋白及miRNAs,进行Western blotting实验、实时荧光定量逆转录聚合酶链反应(qRT-PCR)实验以及免疫荧光染色实验检测相关指标[miR-15b-5p、酪氨酸羟化酶(Th)、脑源性神经营养因子(BDNF)、原肌球蛋白受体激酶B(TrkB)、突触后密度蛋白95(PSD95)]。(2)将100 nmol/L miR-15b-5p模拟物/抑制物序列及各自阴性对照序列分别转染至6孔板上sh-SY5Y细胞中(分别命名为miR-15b-5p模拟物组、miR-15b-5p模拟物对照组及miR-15b-5p抑制物组、miR-15b-5p抑制物对照组),48 h后进行Western blotting实验及qRT-PCR实验,以检测BDNF、TrkB、PSD95蛋白及miR-15b-5p表达改变。(3)将100 ng BDNF 3'端非编码区(3'-UTR)野生型或突变型荧光素酶报告载体质粒以及100 nmol/L miR-15b-5p模拟物/抑制物序列及各自阴性对照序列共转染至24孔板上sh-SY5Y细胞中,得到相应8组细胞,48 h后进行荧光素酶报告载体活性检测实验,以检测各组细胞的荧光素酶活性。结果(1)与对照组相比,PD组小鼠的运动速度明显减慢、落棒潜伏期明显缩短、糖水偏好百分比明显降低、不动时间明显增加;与PD组相比,干预组小鼠的运动速度明显提高、落棒潜伏期明显延长、糖水偏好百分比明显升高,不动时间明显减少;差异均有统计学意义(Ph、BDNF、TrkB、PSD95表达明显降低(100.00±9.20 vs.63.60±12.80;100.00±9.88 vs.71.95±10.00;100.00±5.16 vs.70.37±8.43;100.00±7.01 vs.68.12±10.22),BDNF荧光强度明显降低(100.00±12.99 vs.48.23±12.58);与PD组相比,干预组小鼠黑质中miR-15b-5p表达明显降低,Th、BDNF、TrkB、PSD95表达明显升高(63.60±12.80 vs.90.69±9.84;71.95±10.00 vs.93.31±4.50;70.37±8.43 vs.88.11±4.10;68.12±10.22 vs.89.59±5.93),BDNF荧光强度明显升高(48.23±12.58 vs.83.65±10.52);差异均有统计学意义(P<0.05)。(3)与BDNF 3'-UTR野生型+miR-15b-5p模拟物对照组比较,BDNF 3'-UTR野生型+miR-15b-5p模拟物组细胞中荧光素酶活性明显降低(100.00±5.07 vs.90.59±1.75);与BDNF 3'-UTR野生型+miR-15b-5p抑制物对照组比较,BDNF 3'-UTR野生型+miR-15b-5p抑制物组细胞中荧光素酶活性明显升高(100.00±5.08 vs.152.20±31.87);差异均有统计学意义(P<0.05)。结论miR-15b-5p通过下调BDNF/TrkB/PSD95表达参与PD中抑郁样行为发生。

关键词：帕金森病抑郁 miR-15b-5p 脑源性神经营养因子突触可塑性

SII及NLR、RDW、PLR水平与脑出血后肺部感染及预后的关系

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中华医院感染学杂志 2024年第16期34卷 2462-2466页

作者：朱敏黄从刚罗志华张思武汉市第一医院神经外科湖北武汉430022

目的探究全身免疫炎症指数(SII)和外周血中性粒细胞计数/淋巴细胞计数比值(NLR)、红细胞分布宽度(RDW)、血小板计数/淋巴细胞计数比率(PLR)与脑出血后肺部感染的关系及对患者预后的评估价值。方法选取武汉市第一医院107例脑出血后肺部... 详细信息

目的探究全身免疫炎症指数(SII)和外周血中性粒细胞计数/淋巴细胞计数比值(NLR)、红细胞分布宽度(RDW)、血小板计数/淋巴细胞计数比率(PLR)与脑出血后肺部感染的关系及对患者预后的评估价值。方法选取武汉市第一医院107例脑出血后肺部感染患者为研究对象设为感染组,另选同期80例脑出血后未发生肺部感染的患者归为非感染组,统计所有肺部感染患者的病原学特征,比较两组基线资料和SII、NLR、RDW、PLR水平,治疗后跟踪随访患者3个月,根据改良rankin量表(mRS)评分将感染组患者分为预后良好组(n=69)和预后不良组(n=38),比较预后良好组和预后不良组SII、NLR、RDW、PLR水平,采用受试者工作特征(ROC)曲线评估SII、NLR、RDW、PLR水平对脑出血并肺部感染患者的预后预测价值。结果 107例脑出血肺部感染患者痰液标本培养出148株菌株,革兰阳性菌、革兰阴性菌、真菌占比分别为75.68%、19.59%、4.73%;多因素Logistic回归分析显示,入院NhISS评分、意识障碍、SII、NLR、RDW、PLR是影响脑出血患者肺部感染的危险因素(Psh、NLR、RDW、PLR值均高于预后良好组(P<0.05);ROC曲线分析显示,SII、NLR、RDW和PLR水平联合预测脑出血并肺部感染患者预后的敏感度为92.11%,特异度为60.87%,曲线下面积(AUC)为0.911,联合诊断价值更高。结论脑出血患者SII、NLR、RDW、PLR水平是梗死后肺部感染的危险因素,且对患者预后具有较高的诊断价值。

关键词：全身免疫炎症指数中性粒细胞/淋巴细胞比值红细胞分布宽度血小板/淋巴细胞比率脑出血肺部感染预后病原菌危险因素

Studies on the Surface Interaction and Dispersity of Silver Nanoparticles in Organic Solvents

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Chinese Physics Letters 2000年第9期17卷 697-699页

作者： ZENG Rong RONG min-Zhi ZhANG ming-qiu ZENG han-min Institute of Materials Science Key Laboratory of Polymeric Composite&FYinctional Materials of the Ministry of Education of ChinaZhongshan UniversityGuangzhou 510275

Silver nanoparticles with different sizes have been prepared by microemulsion and have been surface-modified with *** spin resonance results indicate that there exist some kinds of surface local paramagnetic sites in capped Ag nanoparticles,which leads to the relation between electron spin resonance parameters and particle size deviating from Kawabata's *** a strong interaction between nanosilver and *** smaller the particles,the stronger the *** electron microscopy and ultravilolet-visible absorption spectra confirmed that Ag nanoparticles are well dispersed in chloroform,implying that a good dispersity of Ag nanoparticles in polymers could be obtained by means of solution mixing by using chloroform as the solvent.

关键词： interaction. chloroform silver

A new extended structural compound based on saturated Wells-Dawson polyoxoanions

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Chinese Chemical Letters 2009年第11期20卷 1381-1385页

作者： min Xu Jia Liu En Bo Wang Key Laboratory of Polyoxometalate Science of ministry of Education Institute of Polyoxometalate Chemistry Department of Chemistry Northeast Normal University Changchun Jilin 130024 China Department of Chemistry Tonghua Normal University Tonghua Jilin 134002 China

A new 3D extended structural compound, （dpdo）2h2{[Cu（2,2＇-bipy）212（P2W18O62）}.sh2O 1 （dpdo = 4,4＇-bipyridine-N,N＇- dioxide; 2,2＇-bipy = 2,2＇-bipyridine）, has been hydrothermally synthesized and characterized by elemental analyses, IR, TG analyses, cyclic voltammetry, and single-crystal X-my diffraction. Compound 1 is built up of [P2WlsO62]6- cluster as the structural motif covalently linked by [Cu（2,2＇-bipy）2]^2＋ coordination complexes to yield the 1D chains, which axe further in close contact forming a 3D supramolecular framework via aromatic π-π stacking interactions and extensive hydrogen-bonding interactions among polyoxoanions, coordinated 2,2＇-bipy organic ligands, free dpdo organic molecules and lattice water molecules.

关键词： 3D extended structures Dawson-type polyoxometalates Copper-organic complexes

A Simple Approach to Fabricate CdS-SiO_2 hybrid Microspheres by Producing CdS Nanoparticles on the Surface of Thiolated SiO_2 Microspheres

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Chemical Research in Chinese Universities 2006年第1期22卷 76-79页

作者： hAN Kun XIANG Zheng WANG Zheng WANG Chun-lei LI min-jie ZhANG Jun-hu YANG Bai Key Lab of Supramolecular Structure and Materials of ministry of Education College of Chemistry Jilin University Changchun 130012 P. R. China

We have developed a simple synthetic method to prepare the hybrid microspheres of CdS nanoparticles on the surface of silica microspheres modified by（3-mercaptopropyl） trimethoxysilane（MPS）. The--sh groups of MPS can bind with the Cd^2＋ ions on the surface of SiO2. When thioacetamide releases h2S, the nanosized CdS particles（ 1-6 nm） will successfully be generated on the silica surface under the experimental conditions. The size of the CdS nanoparticles was found to be related to the concentration of Cd^2 ＋ feed and the size of silica spheres, the higher the concentration of Cd^2＋ and the larger of silica microspheres, the bigger the size of CdS nanoparticles. Techniques including UV, PL, TEM and XPS were used to characterize the CdS-SiO2 hybrid microspheres.

关键词： Cadmium sulfide Silicon dioxide Nanoparticle hybrid microspheres