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Inhibitory Effects of Selenium on Telomerase Activity and hTERT Expression in Cadmium-transformed 16HBE Cells

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Biomedical and Environmental Sciences 2007年第4期20卷 307-312页

作者： HUA-JIE CHEN RI-AN YU LING-fei HE SHE-JUAN AN ZHI-GANG wu KE-DI YANG XUE-MIN CHEN Department of Occupational and Environmental Health MOE Key Laboratory of Environment and Health School of Public Health Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei China Department of Occupational and Environmental Health MOE Key Laboratory of Environment and Health School of Public Health Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei China Department of Occupational and Environmental Health School of Public HealthGuangdong Pharmaceutical UniversityGuangzhou510320 Environment and Health School of Public Health Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei China Department of Dental Medicine The First Affiliated Hospital of Guangdong Pharmaceutical University Guangzhou 510080 Guangdong China

To investigate the effects of sodium selenite on telomerase activity and expression of hTERT mRNA in cadmium-transformed 16HBE cells. Methods Telomerase activity and expression of genes were measured after cultured cadmium-transformed 16HBE cells were exposed to sodium selenite at different doses （0.625, 1.25, 2.50, 5.00 pmol/L） for 24 hours. Results Selenium decreased telomerase activity in cadmium-transformed 16HBE cells. There existed an obvious dose-effect relationship between the selenium concentration and these changes. The expression of hTERT and c-myc mRNA also decreased but the expression of madl mRNA increased after exposure to selenium for 24 hours. No difference was found in expression of hTRF1 and hTRF2 mRNA after incubated with sodium selenite for 24 hours, compared with control group. Conclusion Selenium inhibits telomerase activity by decreasing hTERT and c-myc mRNA expression and increasing madl mRNA expression in cadmium-transformed 16HBE cells and selenium concentration is significantly correlated with these changes.

关键词： Selenium Cadmium Telomerase Human telomerase reverse transcriptase

Antioxidant activity of alcohol aqueous extracts of Crypthecodinium cohnii and Schizochytrium sp.

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2017年第9期18卷 797-806页

作者： Jin-hui YU Yu WANG Jie SUN fei BIAN Gao CHEN Yan ZHANG Yu-ping BI Ying-jie wu Institute of Genome Engineered Animal Models for Human Disease Dalian Medical University Shandong Center of Crop Germplasm Resources College of Integrative Medicine Dalian Medical University Biotechnology Research Center Shandong Academy of Agricultural Sciences School of Life Sciences Shandong University

Crypthecodinium cohnii(dinoflagellate) and Schizochytrium sp.(thraustochytrid) are the main sources for docosahexaenoic acid(DHA). The present study aimed to evaluate the antioxidant activity of petroleum ether, ethyl acetate, n-butanol, and water fractions of alcohol aqueous extracts of these two microalgae and to provide a theoretical basis for comprehensive utilization. The antioxidant activity was determined by total antioxidant capacity(TAC) determination, 2,2-diphenyl-1-picrylhydrazyl(DPPH) radical scavenging assay, ferrous ion-chelating ability(FICA) assay, and reducing power(RP) assay. The total phenolic content(TPC) and total flavonoid content(TFC) were also measured by the Folin-Ciocalteu and spectrophotometry methods, respectively. The results indicated that the extracts from these two microalgae possessed good antioxidant capacity. Analysis showed that most antioxidant performance indicators(TAC, DPPH, and RP) were positively correlated with the TPC of the extracts, suggesting that the phenolics might be the major components in C. cohnii and Schizochytrium sp., contributing to their antioxidative function. Therefore, the polar fractions of C. cohnii and Schizochytrium sp. could be further examined and considered for application in health products or cosmetics.

关键词： Crypthecodinium cohnii Schizochytrium sp. Alcohol aqueous extract Antioxidant activity Total phenolics

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不同磨料砂轮磨削GCr15的磨削性能研究

佳木斯大学学报（自然科学版） 2024年第6期42卷 72-75页

作者：祝小威刘斐张霖董德胜高秋菊孙龙冯伟白鸽磨料磨具有限公司河南郑州450199 河南省超硬磨料磨削装备重点实验室(河南工业大学) 河南郑州450001

砂轮的磨削性能直接影响了轴承钢的磨削加工质量。为了研究不同磨料砂轮磨削轴承钢GCr15的磨削性能,选取了WA,PA和SG等3种不同磨料砂轮开展磨削试验,从磨削比、磨削功率、工件表面粗糙度、砂轮形貌等方面对砂轮磨削性能进行了对比。结... 详细信息

砂轮的磨削性能直接影响了轴承钢的磨削加工质量。为了研究不同磨料砂轮磨削轴承钢GCr15的磨削性能,选取了WA,PA和SG等3种不同磨料砂轮开展磨削试验,从磨削比、磨削功率、工件表面粗糙度、砂轮形貌等方面对砂轮磨削性能进行了对比。结果表明:不同的磨料砂轮在磨削轴承钢时的磨削性能各不相同,其中WA砂轮磨削表面质量最高,PA砂轮的磨削比最高,两者的表面黏屑状态高于SG砂轮,但后者的锋利性更高。分析结果对于合理选择轴承磨削砂轮提供了参考。

关键词：砂轮 GCr15 磨削性能

Visualization of hydraulic fracture interacting with pre-existing fracture

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Petroleum Science 2023年第6期20卷 3723-3735页

作者： Zi-Xiao Xie Xiao-Guang wu Teng-Da long Zhong-Wei Huang Gen-Sheng Li Wen-Chao Zou Zhao-Wei Sun State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum-BeijingBeijing102249China

Hydraulic fracturing is considered the main stimulation method to develop shale gas reservoirs. Due to its strong heterogeneity, the shale gas formation is typically embedded with geological discontinuities such as bedding planes and natural fractures. Many researchers realized that the interaction between natural fractures and hydraulic fractures plays a crucial role in generating a complex fracture network. In this paper, true tri-axial hydraulic fracturing tests were performed on polymethyl methacrylate (PMMA), on which pre-existing fracture was pre-manufactured to simulate natural fracture. A cohesive model has been developed to verify the results of the experimental tests. The key findings demonstrate that the experimental results agreed well with the numerical simulation outcomes where three main interaction modes were observed: crossing;being arrested by opening the pre-existing fracture;being arrested without dilating the pre-existing fracture. Crossing behavior is more likely to occur with the approaching angle, horizontal stress difference, and injection rate increase. Furthermore, the higher flow rate might assist in reactivating the natural fractures where both sides of the pre-existing fractures were reactivated as the injection rate increased from 5 to 20 mL/min. Additionally, hydraulic fractures show a tendency to extend vertically rather than along the direction of maximum horizontal stress when they are first terminated at the interface. This research may contribute to the field application of hydraulic fracturing in shale gas formation.

关键词： Hydraulic fracturing Natural fracture Fracture propagation Interaction mode PMMA

Influence of CeO_2 and La_2O_3 on properties of palladium catalysts used for emission control of natural gas vehicles

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Journal of Natural Gas Chemistry 2009年第4期18卷 415-420页

作者： Yile Li Xiaoyu Zhang Enyan long Hongmei Li Dongdong wu Li Cai Maochu Gong Yaoqiang Chen Key Laboratory of Green Chemistry ＆ Technology of the Ministry of Education College of Chemistry Sichuan University Chengdu 610064 Sichuan China

Pd/YZ-Al2O3 （Y and Zr modified Al2O3, and hereafter, labelled as A1） catalysts with 4 wt% additive CeO2 and/or La2O3 were prepared and characterized by X-ray photoelectron spectroscopy （XPS）, NO-temperature programmed desorption （NO-TPD）, Nz-adsorption/desorption （Branauer-Emmet-Teller BET method）, X-ray diffraction （XRD） and CO-chemisorption. Catalytic activities for CH4, CO and NO conversion were tested in a gas mixture simulated the emissions from natural gas vehicles （NGVs） operated under stoichiometric conditions. The results indicated that all catalysts exhibited excellent catalytic performances for CH4 and CO oxidation and the promoting effect of CeO2 or La2O3 was significant for NO conversion. XPS results showed that the electron density around Pd was increased by CeO2 and/or La2O3, the binding energy of Pd 3d decreased as the order： Pd/Al 〉 Pd/Ce/Al 〉 Pd/La/Al 〉 Pd/CeLa/Al. The electron-rich Pd showed Rh-like catalytic properties which exhibited good activity for the reduction of NO. NO-TPD results showed that the addition of CeO2 and/or La2O3 increased NO adsorption on surface, and promoted the conversion of NO.

关键词： NGVs under stoichiometric condition palladium catalyst XPS NO-TPD NO conversion methane conversion

Strong Convergence Theorems for Asymptotically Strictly Pseudocontractive Maps in Hilbert Spaces

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Journal of Mathematical Research and Exposition 2009年第1期29卷 43-51页

作者： QIN Xiao long wu Chang Qun SHANG Mei Juan Department of Mathematics Tianjin Polytechnic University Tianjin 300160 China School of Business and Administration Henan University Henan 475001 China Department of Mathematics Shijiazhuang University Hebei 050035 China

The Mann iterations have no strong convergence even for nonexpansive mappings in Hilbert spaces. The aim of this paper is to propose a modification of the Mann iterations for strictly asymptotically pseudocontractive maps in Hilbert spaces to have strong convergence. Our results extend those of Kim, Xu, Nakajo, Takahashi and many others.

关键词： nonexpansive mappings strictly pseudocontractive mappings Hilbert spaces projection.

Aldosterone induces inflammatory cytokines in penile corpus cavernosum by activating the NF-κB pathway

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Asian Journal of Andrology 2018年第1期20卷 24-29页

作者： fei wu Zu-Quan Xiong Shan-Hua Mao Ji-Meng Hu Jian-Qing Wang Hao-Wen Jiang Qiang Ding Department of Urology Fudan Institute of Urology Huashan Hospital Fudan University Shanghai 200040 China

Emerging evidence indicates that aldosterone and mineralocorticoid receptors （MRs） are associated with the pathogenesis of erectile dysfunction. However, the molecular mechanisms remain largely unknown. In this study, freshly isolated penile corpus cavernosum tissue from rats was treated with aldosterone, with or without MRs inhibitors. Nuclear factor （NF）-kappa B （NF-κB） activity was evaluated by real-time quantitative PCR, luciferase assay, and immunoblot. The results demonstrated that mRNA levels of the NF-κB target genes, including inhibitor of NF-κB alpha （IκB-α, NF-κB1, tumor necrosis factor-alpha （TNF-α, and interleukin 6 （IL-6）, were higher after aldosterone treatment. Accordingly, phosphorylation of p65/RelA, IκB-α, and inhibitor of NF-κB kinase-β was markedly increased by aldosterone. Furthermore, knockdown of MRs prevented activation of the NF-κB canonical pathway by aldosterone. Consistent with this finding, ectopic overexpression of MRs enhanced the transcriptional activation of NF-κB by aldosterone. More importantly, the MRs antagonist, spironolactone blocked aldosterone-mediated activation of the canonical NF-κB pathway. In conclusion, aldosterone has an inflammatory effect in the corpus cavernosum penis, inducing NF-κB activation via an MRs-dependent pathway, which may be prevented by selective MRs antagonists. These data reveal the possible role of aldosterone in erectile dysfunction as well as its potential as a novel pharmacologic target for treatment.

关键词： aldosterone erectile dysfunction NF-κB receptors

安康欣胶囊辅助小切口胃癌根治术治疗胃癌患者的疗效研究

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世界中西医结合杂志 2024年第7期19卷 1354-1360,1365页

作者：李翰嵩姚远张磊赵辉韩龙才李景武河北省唐山市人民医院胃肠外二科河北唐山063001

目的观察安康欣胶囊辅助小切口胃癌根治术治疗胃癌(Gastric carinoma,GC)的临床疗效。方法选取2021年8月-2022年8月期间河北省唐山市人民医院收治的70例胃癌患者,按随机数字表法分为对照组和观察组,每组各35例。对照组予以小切口胃癌根... 详细信息

目的观察安康欣胶囊辅助小切口胃癌根治术治疗胃癌(Gastric carinoma,GC)的临床疗效。方法选取2021年8月-2022年8月期间河北省唐山市人民医院收治的70例胃癌患者,按随机数字表法分为对照组和观察组,每组各35例。对照组予以小切口胃癌根治术,术后进行营养干预,观察组在对照组基础上加用安康欣胶囊。两组疗程均为4周。观察比较两组患者治疗前后中医证候积分(纳食呆滞、胃脘部隐痛、恶心反酸、腹部肿块、大便稀溏)、营养指标[前白蛋白(Prealbumin,PA)、血红蛋白(Hemoglobin,Hb)、总蛋白(Total protein,TP)、白蛋白(Albumin,Alb)、转铁蛋白(Transferrin,TRF)]、胃肠功能指标(肠鸣音恢复时间、首次排气时间、饮食恢复时间、首次排便时间)、肿瘤标志物[癌胚抗原(Carcinoembryonic antigen,CEA)、糖类抗原-724(Carbohydrate antigen-724,CA-724)、糖类抗原-199(Carbohydrate antigen-199,CA-199)、恶性肿瘤生长因子(Malignant tumor growth factor,TSGF)]、复发转移指标[基质金属蛋白酶-2(Matrix metalloproteinase-2,MMP-2)、基质金属蛋白酶-9(Matrix metalloproteinase-9,MMP-9)、血管内皮生长因子(Vascular endothelial growth factor-A,VAGF-A)及VAGF-C]、免疫功能[T淋巴细胞亚群(CD3^(+)、CD4^(+)、CD8^(+)、CD4^(+)/CD8^(+))]的变化情况,随访记录生存期及复发转移率。结果治疗后两组患者中医主症纳食呆滞、胃脘部隐痛、恶心反酸、腹部肿块、大便稀溏证候积分均较治疗前明显降低,差异有统计学意义(P0.05),观察组CD3^(+)、CD4^(+)和CD4^(+)/CD8^(+)指标均较治疗前升高,CD8^(+)较治疗前降低,差异有统计学意义(P<0.05);且观察组血清CD3^(+)、CD4^(+)、CD4^(+)/CD8^(+)均明显高于对照组,CD8^(+)明显低于对照组,差异有统计学意义(P<0.01)。两组患者复发率和转移率比较,差异有统计学意义(χ^(2)=5.535、5.878,P=0.019、0.015)。结论安康欣胶囊辅助小切口胃癌根治术能控制胃癌患者病情,促进胃功能恢复,改善营养状况及免疫功能,下调肿瘤标志物及复发转移相关指标,延长生存期,减少复发和转移。

关键词：安康欣胶囊胃癌小切口胃癌根治术肿瘤标志物免疫功能

A sensitive and compact mercury analyzer by integrating dielectric barrier discharge induced cold vapor generation and optical emission spectrometry

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Chinese Chemical Letters 2017年第2期28卷 189-196页

作者： An-Qin Leng Yun-fei Tian Ming-Xuan Wang Li wu Kai-Lai Xu Xian-Deng Hou Cheng-Bin Zheng College of Chemistry Sichuan University Chengdu 610064 China Analytical & Testing Center Sichuan University Chengdu 610064 China

An environmentally friendly,low power consuming,sensitive and compact mercury analyzer was developed for the determination of mercury in water samples by integrating a thin film dielectric barrier discharge induced cold vapor reactor and a dielectric barrier discharge optical emission spectrometer into a small polymethyl methacrylate plate（10.5 cm length×8.0 cm width×1.2 cm height）.Mercury cold vapor was generated when standard or sample solutions with or without formic acid were introduced to the reactor to form thin film liquid and exposed to microplasma irradiation and subsequently separated from the liquid phase for transport to the microplasma and detection of its atomic *** of detection of 0.20 μg L^-1 and 2.6 μg L^-1 were obtained for the proposed system using or not using formic acid,*** to the conventional microplasma optical emission spectrometry used for mercury analysis,this system not only retains the good limit of detection amenable to the determination of mercury in real samples,but also reduces power consumption,eliminates the generation of hydrogen and avoids the use of toxic or unstable *** validation was demonstrated by analysis of a certified reference material of water sample and three real water samples with good spike recoveries（88-102%）.

关键词： Mercury Real time field analysis Microplasma Optical emission spectrometry Cold vapor generation Miniaturization