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Targeting the chromatin structural changes of antitumor immunity
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作者 Nian-nian Li Deng-xing Lun +22 位作者 Ningning Gong Gang Meng Xin-ying Du He Wang Xiangxiang Bao Xin-yang Li Ji-wu Song Kewei Hu Lala Li Si-ying Li Wenbo Liu Wanping Zhu Yunlong Zhang Jikai Li Ting Yao Leming Mou Xiaoqing Han Furong Hao Yongcheng Hu Lin Liu Hongguang Zhu Yuyun Wu Bin Liu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第4期460-482,共23页
Epigenomic imbalance drives abnormal transcriptional processes,promoting the onset and progression of cancer.Although defective gene regulation generally affects carcinogenesis and tumor suppression networks,tumor imm... Epigenomic imbalance drives abnormal transcriptional processes,promoting the onset and progression of cancer.Although defective gene regulation generally affects carcinogenesis and tumor suppression networks,tumor immunogenicity and immune cells involved in antitumor responses may also be affected by epigenomic changes,which may have significant implications for the development and application of epigenetic therapy,cancer immunotherapy,and their combinations.Herein,we focus on the impact of epigenetic regulation on tumor immune cell function and the role of key abnormal epigenetic processes,DNA methylation,histone post-translational modification,and chromatin structure in tumor immunogenicity,and introduce these epigenetic research methods.We emphasize the value of small-molecule inhibitors of epigenetic modulators in enhancing antitumor immune responses and discuss the challenges of developing treatment plans that combine epigenetic therapy and immuno-therapy through the complex interaction between cancer epigenetics and cancer immunology. 展开更多
关键词 Antitumor immunity Chromatin structural Cancer epigenetics DNA methylation Histone modification CHEMOTHERAPY
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Effects of B[a]P-UVA Co-Exposure on Epigenetic Marks of Isolated Skin Cells and Impact of an Arundo donax L. Extract of These Changes
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作者 Marie M. Dorr Magali Favre-Mercuret +1 位作者 Katell Vié Richard Fitoussi 《Journal of Cosmetics, Dermatological Sciences and Applications》 2024年第3期253-269,共17页
Background: Extrinsic aging results from environmental stressors such as UVR or pollutants. While the effects of single pollutants are better understood, those of their combination remain poorly scrutinized. Objective... Background: Extrinsic aging results from environmental stressors such as UVR or pollutants. While the effects of single pollutants are better understood, those of their combination remain poorly scrutinized. Objective: Building on a study showing downregulation of several processes upon co-exposure to B[a]P and UVA, we investigated changes induced by epigenetic marks. Materials and Methods: Human primary fibroblasts and HaCaT cells were exposed to B[a]P and UVA. After 24 hours, exposed and unexposed cells were compared to assess DNA methylation. Focusing on HaCaT, multiplex assays enabled quantifying histone H3 modifications and evaluating four splicing factors (SRSF1, SRSF3, SFPQ, and SF3B1) by immunohistochemical labeling. The expression of keratinocyte-/fibroblast-relevant genes was assessed by RT-qPCR. Finally, the impact of an Arundo donax L. extract added 24 hours before B[a]P-UVA co-exposure was analyzed. Results: Exposure to B[a]P-UVA raised DNA methylation (HaCaT: ×3.6, fibroblasts: ×1.9), an increase prevented by the extract. In HaCaT cells, B[a]P-UVA increases the frequency of S10P (+38%). When exposure was preceded by extract treatment, the frequency of several methylations was impacted. B[a]P-UVA only induced the expression of SRSF1 and SFPQ in HaCaT (+46% and +34%). Treatment with the extract abolished this effect. Co-exposure increases the expression of inflammation-related genes (IL-1α, IL-1β) in HaCaT cells and decreases those of AQP3, KRT15, and SOD2. The extract has little effect on these changes. In primary fibroblasts, exposure to B[a]P-UVA lowered the expression of LOXL2, LUM, and TGFBR2 (−38%, −59%, and −51%, respectively), and the extract did not affect these modifications. Conclusion: Within 24 hours, a single B[a]P-UVA co-exposure changes epigenetic marks of skin cells but has only mild effects on gene expression. An Arundo donax L. extract can prevent part of the epigenetic marks’ changes and could stimulate the expression of some genes in primary fibroblasts. 展开更多
关键词 Extrinsic Aging DNA methylation Histone H3 Splicing Factors Arundo donax L.
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A change of phenolic acids content in poplar leaves induced by methyl sali-cylate and methyl jasmonate 被引量:13
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作者 安钰 沈应柏 +1 位作者 吴丽娟 张志翔 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第2期107-110,共4页
The contents of seven different phenolic acids such as gallic acid, catechinic acid, pyrocatechol, caffeic acid, coumaric acid, ferulic acid and benzoic acid in the poplar leaves (Populus Simonii×Populus Pyramib... The contents of seven different phenolic acids such as gallic acid, catechinic acid, pyrocatechol, caffeic acid, coumaric acid, ferulic acid and benzoic acid in the poplar leaves (Populus Simonii×Populus Pyramibalis c.v and Populus deltoids) suffocated by Methyl jasmonate (MeJA) and Methyl salicylate (MeSA) were monitored for analyzing their functions in interplant communications by using high-pressure liquid chromatography (HPLC).The results showed that the contents of phenolic acids had obviously difference in leaves exposed to either MeSA or MeJA.When P.deltoides leaves exposed to MeJA or MeSA, the level of gallic acid, coumaric acid, caffeic acid, ferulic acid and benzoic acid was increased, gallic acid in leaves treated with MeJA comes to a peak at 24 h while to a peak at 12-d having leaves treated with MeSA.When P.Simonii ×P.Pyramibalis c.v leaves were exposed to MeJA or MeSA, the level of gallic acid, pyrocatechol and ferulic acid was increased; The catechinic acid and benzoic acid had a little drop; The caffeic acid and coumaric acid were undetected in both suffocated and control leaves.This changed pattern indicated that MeJA and MeSA can act as airborne signals to induce defense response of plants. 展开更多
关键词 methyl salicylate (MeSA) methyl jasmonate (MeJA) Airborne signal Phenolic acid Induce resistance
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Modification of ACFs by chemical vapor deposition and its application for removal of methyl orange from aqueous solution 被引量:3
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作者 王丽平 黄柱成 张明瑜 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第2期530-537,共8页
Viscose activated carbon fibers (ACFs) were characterized using specific surface area, scanning electron modified with chemical vapor deposition (CVD). The samples were microscopy (SEM), pore size distribution a... Viscose activated carbon fibers (ACFs) were characterized using specific surface area, scanning electron modified with chemical vapor deposition (CVD). The samples were microscopy (SEM), pore size distribution and Fourier transform infrared spectroscopy (FTIR). Batch adsorption experiments were carried out to investigate the adsorption behavior of modified ACFs for methyl orange(MO) from its aqueous solutions. The results show that the adsorption isotherms of MO onto modified ACFs well follows the Langmuir isotherm equation. The adsorption kinetics of MO can be well described by the pseudo second-order kinetic model. The adsorption process involves the intra-particle diffusion, but is not the only rate-controlling step. Thermodynamic parameters including AG, AH and AS were calculated, suggesting that the adsorption of MO onto modified ACFs is a spontaneous, exothermic and physisorption process. FTIR result indicates that the major adsorption mechanism of modified ACFs for MO is hydrogen bond. 展开更多
关键词 viscose activated carbon fiber chemical vapor deposition MODIFICATION methyl orange adsorption isotherm kinetics THERMODYNAMICS
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Comparative Studies on Degradation of Methyl Orange by Nanostructured Zinc and Zinc Oxide Films
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作者 吴炳俊 郝常山 +1 位作者 谢斌 李明 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第5期615-620,622,共7页
Nanostructured zinc and zinc oxide films were prepared by magnetron sputtering processes and succeeded air annealing treatments. Comparison of reductive degradation rate of methyl orange (MO) by zinc films and photo... Nanostructured zinc and zinc oxide films were prepared by magnetron sputtering processes and succeeded air annealing treatments. Comparison of reductive degradation rate of methyl orange (MO) by zinc films and photocatalytic degradation rate of MO by zinc oxide films was carried out. Both reductive degradation and photocatalytic degradation process of MO by zinc and zinc oxide films can be described by first order kinetic model. It was found that although MO liquid was most quickly decolorized by metallic zinc films, the mineraliza- tion of MO was not thorough. Observation of extra ultraviolet absorption peaks indicated the formation of aromatic intermediates. On the other hand, although the photocatalytic degradation rate of MO liquid by ZnO films was only as about 1/4 large as the reductive degradation rate by zinc films, no signs of aromatic intermediates were found. Moreover, it was found that partially oxidized zinc oxide film showed higher photocatalytic efficiency than the totally oxidized ZnO films. Synergy effect between zinc and zinc oxide phase in the partially oxidized films was considered to be responsible for the higher photocatalytic efficiency. 展开更多
关键词 methyl orange ZINC ZnOx ZNO Reductive degradation PHOTOCATALYSIS
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基于ACE/AngⅡ/AT1R通路探讨补肾降压方对盐敏感性高血压大鼠肾纤维化的作用机制
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作者 刘巍 熊兴江 +4 位作者 刘红旭 张竹华 王阶 褚福永 谭玉培 《世界中医药》 CAS 北大核心 2024年第9期1269-1275,共7页
目的:探讨补肾降压方对盐敏感性高血压DS大鼠肾纤维化及肾素血管紧张素转换酶-血管紧张素Ⅱ-血管紧张素Ⅱ1型受体(ACE-AngⅡ-AT1R)信号通路的调节作用,探讨其防治高血压肾损害的作用机制。方法:选用盐敏感性高血压大鼠(Dahl salt-sensit... 目的:探讨补肾降压方对盐敏感性高血压DS大鼠肾纤维化及肾素血管紧张素转换酶-血管紧张素Ⅱ-血管紧张素Ⅱ1型受体(ACE-AngⅡ-AT1R)信号通路的调节作用,探讨其防治高血压肾损害的作用机制。方法:选用盐敏感性高血压大鼠(Dahl salt-sensitve,DS)48只,随机数字表法分为低盐组、高盐组、缬沙坦组和补肾降压组,喂食以不同浓度钠盐饲料造模后,予药物干预8周。于干预前后测量血压。干预后酶联免疫吸附测定(ELISA)血清中血肌酐(Cr)、尿素氮(BUN)、血管紧张素Ⅱ(AngⅡ)及转化生长因子-β_(1)(TGF-β_(1))的含量。苏木精-伊红(HE)染色观察肾组织病理学改变情况,Masson染色观察肾纤维化程度。反转录PCR(RT-PCR)及蛋白质印迹法分别检测肾脏血管紧张素转化酶(ACE)及血管紧张素Ⅱ1型受体(AT1R)mRNA及蛋白表达水平。结果:喂食3周不同浓度盐后,喂食高盐各组收缩压均较低盐组升高(P<0.01)。干预后,与低盐组比较,高盐组收缩压升高,Cr、BUN升高,血清AngⅡ及TGF-β_(1)水平升高,HE及Masson染色显示肾脏纤维化程度加重,肾脏ACE及AT1R蛋白及mRNA表达升高(P<0.01)。与高盐组比较,缬沙坦组及补肾降压组收缩压降低,Cr、BUN降低,血清AngⅡ及TGF-β_(1)水平降低,肾脏纤维化程度减轻,肾脏ACE及AT1R蛋白及mRNA表达降低(P<0.05,P<0.01)。结论:补肾降压方有平稳降压,改善肾功能的作用,其作用机制可能与调节ACE/AngⅡ/AT1R轴进而抑制TGF-β_(1)达到延缓肾纤维化相关。 展开更多
关键词 盐敏感性高血压 补肾降压方 高血压肾损害 肾纤维化 ACE/angⅡ/AT1R轴
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Epigenetic changes in the regulation of carotenoid metabolism during honeysuckle flower development 被引量:5
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作者 Hang Yu Na Cui +2 位作者 Kun Guo Wen Xu Haifeng Wang 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第3期577-588,共12页
Flower development is one of the most vital pathways in plant development, during which the epigenetic regulation of gene expression is essential. DNA methylation, the most conserved epigenetic modification, participa... Flower development is one of the most vital pathways in plant development, during which the epigenetic regulation of gene expression is essential. DNA methylation, the most conserved epigenetic modification, participates in gene expression regulation and transposable element silencing. Honeysuckle(Lonicera japonica) is an important medicinal plant renowned for its colorful and fragrant flowers. Honeysuckle flowers change color from white to gold as a result of carotenoid accumulation during development. However, the role of DNA methylation in flower color changes is not well understood in L. japonica. Here, we performed whole-genome bisulfite sequencing and transcriptome sequencing during flowering development in honeysuckle. The results showed that a decrease in the levels of genome-wide average DNA methylation during flower development and changes in DNA methylation were associated with the expression of demethylase genes. Moreover, many genes involved in carotenoid biosynthesis and degradation, such as Lj PSY1, LjPDS1, LjLCYE, and LjCCD4, have altered expression levels because of hypomethylation, indicating that DNA methylation plays an important role in flower color changes in honeysuckle. Taken together, our data provide epigenetic insights into flower development and color change in honeysuckles. 展开更多
关键词 Lonicera japonica DNA methylation Epigenetic regulation Gene expression Carotenoid metabolism
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Photodegradation of methyl orange by BiOI-sensitized TiO_2 被引量:10
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作者 Li Huiquan Cui Yumin +2 位作者 Hong Wenshan Hua Lin Tao Dongliang 《Rare Metals》 SCIE EI CAS CSCD 2012年第6期604-610,共7页
BiOI-sensitized titanium dioxide (TiO2) photocatalysts were prepared by a deposition method at room temperature and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller su... BiOI-sensitized titanium dioxide (TiO2) photocatalysts were prepared by a deposition method at room temperature and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller surface area measurements. The photocatalytic activities of the catalysts were evaluated for the degradation of methyl orange (MO) solution under UV and visible light irradiation. The effects of catalyst amount, initial pH value, initial concentration of MO, as well as KI amount were investigated. The repeatability of photocatalytic activity of the 1.7% BiOI/TiO2 catalyst was also tested. It is shown that BiOI sensitization enhances the photocatalytic activities of TiO2. With BiOI content increasing, the photocatalytic activities of BiOI/TiO2 under UV and visible light irradiation first increase, reaching a maximum around BiOI content of 1.7%, and then decrease with further increasing BiOI content. The 1.7% BiOI/TiO2 catalyst obviously exhibits much higher visible light photocatalytic activity than P25, and its UV light photocatalytic activity is slightly higher than that of P25. Under the conditions of a catalytic dose of 1.5 g.L-1, initial pH of 3.0, initial MO concentration of 20 mg.L-1, UV power of 300 W, and air flow rate of 0.8 L.min-1, complete degradatio is achieved within 60 min. The repeatability of photocatalytic activity of the 1.7% BiOI/TiO2 catalyst is highly reliable. 展开更多
关键词 sensitized TiO2 BiOI photocatalytic degradation methyl orange
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天麻钩藤饮对妊娠期高血压患者血压及电解质、PRA、AngⅡ和UⅡ水平的影响分析 被引量:1
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作者 刘晓华 柳伟伟 朱晓明 《广州中医药大学学报》 CAS 2024年第5期1188-1195,共8页
【目的】研究天麻钩藤饮对妊娠期高血压肝阳偏亢型患者的血压及电解质、肾素活性(PRA)、血管紧张素Ⅱ(AngⅡ)和尾加压素Ⅱ(UⅡ)水平变化的影响。【方法】将468例妊娠期高血压肝阳偏亢型患者随机分为研究组和对照组,每组各234例。对照组... 【目的】研究天麻钩藤饮对妊娠期高血压肝阳偏亢型患者的血压及电解质、肾素活性(PRA)、血管紧张素Ⅱ(AngⅡ)和尾加压素Ⅱ(UⅡ)水平变化的影响。【方法】将468例妊娠期高血压肝阳偏亢型患者随机分为研究组和对照组,每组各234例。对照组给予硫酸镁联合拉贝洛尔治疗,研究组在对照组的基础上加用天麻钩藤饮治疗,疗程为5 d。观察2组患者治疗前后收缩压(SBP)、舒张压(DBP)及电解质和血清PRA、AngⅡ、UⅡ水平的变化情况,并分析2组患者的临床疗效和不良反应发生情况。【结果】(1)疗效方面:治疗5 d后,研究组的痊愈率和总有效率分别为12.82%(30/234)、95.30%(223/234),对照组分别为5.56%(13/234)、82.05%(192/234);组间比较,研究组的痊愈率、总有效率(χ^(2)检验)和总体疗效(秩和检验)均明显优于对照组(P<0.05或P<0.01)。(2)血压方面:治疗后,2组患者的SBP、DBP水平均较治疗前降低(P<0.01),且研究组治疗后的SBP、DBP水平均明显低于对照组(P<0.01)。(3)电解质水平方面:治疗后,2组患者的血浆钙离子、镁离子以及红细胞钙离子、镁离子水平均较治疗前升高(P<0.01),但研究组治疗后的血浆钙离子、镁离子以及红细胞镁离子水平均明显低于对照组(P<0.01)。(4)血清PRA、AngⅡ和UⅡ水平方面:治疗后,2组患者的血清PRA、AngⅡ和UⅡ水平均较治疗前降低(P<0.01),且研究组治疗后的血清PRA、AngⅡ和UⅡ水平均明显低于对照组(P<0.01)。(5)不良反应方面:2组患者的头痛、失眠、咳嗽、心悸等不良反应发生率及总发生率比较,差异均无统计学意义(P>0.05)。【结论】天麻钩藤饮在改善妊娠期高血压肝阳偏亢型患者的血压、电解质水平以及血清PRA、AngⅡ、UⅡ水平方面效果显著,且不会增加不良反应发生风险。 展开更多
关键词 妊娠期高血压 肝阳偏亢型 天麻钩藤饮 血压 电解质 肾素活性(PRA) 血管紧张素Ⅱ(angⅡ) 尾加压素Ⅱ(UⅡ)
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调控Ang/Tie信号通路治疗眼底新生血管性疾病的研究进展
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作者 杨婧研(综述) 魏文斌(审校) 《中华实验眼科杂志》 CAS CSCD 北大核心 2024年第5期467-472,共6页
抗血管内皮生长因子(VEGF)治疗应用于眼底新生血管疾病领域以来,在提高视力、稳定疾病病变和在某些情况下逆转疾病方面显示了卓越的效果。但抗VEGF治疗需要频繁玻璃体内注射给药,患者治疗负担重,长期疗效受影响。前期临床研究发现,调控... 抗血管内皮生长因子(VEGF)治疗应用于眼底新生血管疾病领域以来,在提高视力、稳定疾病病变和在某些情况下逆转疾病方面显示了卓越的效果。但抗VEGF治疗需要频繁玻璃体内注射给药,患者治疗负担重,长期疗效受影响。前期临床研究发现,调控血管生成素(Ang)/含免疫球蛋白样环和上皮生长因子样域酪氨酸激酶(Tie)通路在眼底新生血管疾病的治疗中有较好的效果。目前已发布了3个Ang/Tie通路阻断药物治疗眼底新生血管疾病的临床研究数据,其中靶向VEGF-A和Ang-2的双特异性免疫球蛋白G1抗体faricimab进入了Ⅲ期临床试验并达到终点,faricimab的2种延长治疗间隔(12周和16周)的给药方案均被证实有效。本文基于已发表的研究报告,就调控Ang/Tie通路在眼底新生血管性疾病治疗中的作用及临床应用作一综述,总结分析Ang/Tie通路的作用机制以及未来药物的应用前景。 展开更多
关键词 眼底新生血管疾病 抗新生血管生成 ang/Tie通路
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Mechanisms of Enhancement of Photocatalytic Properties and Activity of Nd^(3+)-Doped TiO_2 for Methyl Orange Degradation 被引量:6
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作者 侯梅芳 李芳柏 +3 位作者 李瑞丰 万洪富 周国逸 谢克昌 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第4期542-546,共5页
Nd^(3+)-doped TiO_2 powders were prepared by the sol-gel method. Their crystal pattern and parameter, the specific surface area, the surface chemical state of Ti and the ratio of O/Ti were characterized. The results s... Nd^(3+)-doped TiO_2 powders were prepared by the sol-gel method. Their crystal pattern and parameter, the specific surface area, the surface chemical state of Ti and the ratio of O/Ti were characterized. The results show that Nd impurity hinders the crystal transformation, and decreases the relative intensity of (101) peak. The crystallite sizes of Nd^(3+)-doped TiO_2 powders decrease while their specific surface area increase owing to the Nd^(3+) doping. The XPS measurement shows that the content of Ti(Ⅲ) and ratio of O/Ti on their surfaces increase significantly with the increase of Nd^(3+) dosage. The adsorption and photodegradation experiments show that the optimum molar content of Nd^(3+) is 1.2%. 展开更多
关键词 catalytic chemistry PHOTOCATALYSIS TiO_2 neodymium methyl orange rare earths
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Photocatalytic Dye Methyl Orange Decomposition on Ternary Sulfide (CdIn2S4) under Visible-light 被引量:5
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作者 Xiao Dan YU Xue Song QU +1 位作者 Yi Hang GUO Chang Wen HU 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第9期1259-1262,共4页
A novel and efficient photocatalyst, CdIn2S4, was simply prepared by a programmed temperature hydrothermal method. The product had a nanometer size (10-15 nm) and strong absorption in the range of 200 to 580 nm, and... A novel and efficient photocatalyst, CdIn2S4, was simply prepared by a programmed temperature hydrothermal method. The product had a nanometer size (10-15 nm) and strong absorption in the range of 200 to 580 nm, and it exhibited visible-light photocatalytic activity to decompose dye methyl orange in aqueous system. 展开更多
关键词 Ternary sulfides hydrothermal treatment visible-light photocatalysis methyl orange
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Effects of maternal methyl donor intake during pregnancy on ileum methylation and function in an intrauterine growth restriction pig model 被引量:1
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作者 Yan Lin Jiangnan Wu +8 位作者 Yong Zhuo Bin Feng Zhengfeng Fang Shengyu Xu Jian Li Hua Zhao De Wu Lun Hua Lianqiang Che 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1173-1189,共17页
Background Intrauterine growth retardation(IUGR)affects intestinal growth,morphology,and function,which leads to poor growth performance and high mortality.The present study explored whether maternal dietary methyl do... Background Intrauterine growth retardation(IUGR)affects intestinal growth,morphology,and function,which leads to poor growth performance and high mortality.The present study explored whether maternal dietary methyl donor(MET)supplementation alleviates IUGR and enhances offspring’s growth performance by improving intestinal growth,function,and DNA methylation of the ileum in a porcine IUGR model.Methods Forty multiparous sows were allocated to the control or MET diet groups from mating until delivery.After farrowing,8 pairs of IUGR and normal birth weight piglets from 8 litters were selected for sampling before suckling colostrum.Results The results showed that maternal MET supplementation tended to decrease the IUGR incidence and increased the average weaning weight of piglets.Moreover,maternal MET supplementation significantly reduced the plasma concentrations of isoleucine,cysteine,urea,and total amino acids in sows and newborn pig-lets.It also increased lactase and sucrase activity in the jejunum of newborn piglets.MET addition resulted in lower ileal methionine synthase activity and increased betaine homocysteine S-methyltransferase activity in the ileum of newborn piglets.DNA methylation analysis of the ileum showed that MET supplementation increased the methyla-tion level of DNA CpG sites in the ileum of newborn piglets.Down-regulated differentially methylated genes were enriched in folic acid binding,insulin receptor signaling pathway,and endothelial cell proliferation.In contrast,up-regulated methylated genes were enriched in growth hormone receptor signaling pathway and nitric oxide biosyn-thetic process.Conclusions Maternal MET supplementation can reduce the incidence of IUGR and increase the weaning litter weight of piglets,which may be associated with better intestinal function and methylation status. 展开更多
关键词 ILEUM Intrauterine growth restriction methyl donor methylATION SOWS
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Sonocatalytic degradation of methyl orange in the presence of (nanometer and ordinary) anatase TiO_2 powders 被引量:3
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作者 WANGJun GUOBao-dong ZHANGZhao-hong ZHANGXiang-dong WUJing LIHong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第3期414-418,共5页
The nanometer and ordinary anatase titanium dioxide(TiO_2) powders were adopted as the sonocatalysts for the degradation of methyl orange used as a model compound for the first time. It was found that the sonocatalyti... The nanometer and ordinary anatase titanium dioxide(TiO_2) powders were adopted as the sonocatalysts for the degradation of methyl orange used as a model compound for the first time. It was found that the sonocatalytic degradation effect of methyl orange in the presence of TiO_2 powder were much better than that without TiO_2, but the sonocatalytic activity of the nanometer anatase TiO_2 particle was obviously higher than that of ordinary anatase TiO_2 particle. Although there are many factors influencing sonocatalytic degradation of methyl orange, the experimental results showed that the best degradation ratio of methyl orange could be obtained when the experimental conditions were: initial concentration 15 mg/L, nanometer anatase TiO_2 adding amount 750 mg/L, ultrasonic frequency 40 kHz, output power 50 W, pH = 3.0 and temperature 40℃ within 150 min. In addition, the catalytic activity of reused nanometer anatase TiO_2 catalyst was also studied and found to decline gradually comparing with initial nanometer anatase TiO_2 catalyst. All experiments indicated that the method of the sonocatalytic degradation of organic pollutants in the presence of TiO_2 powder was an advisable choice for non- or low-transparent organic wastewaters. 展开更多
关键词 titanium dioxide(TiO_2) sonocatalytic degradation methyl orange nanometer anatase ordinary anatase
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Hydrothermal Synthesis of H_3PW_(12)O_(40)/TiO_2 Nanometer Photocatalyst and Its Catalytic Performance for Methyl Orange 被引量:4
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作者 FENG Chang-gen SHANG Hai-ru 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第3期366-370,共5页
H3PW12O40/TiO2 nanometer photocatalyst was prepared by one step hydrothermal synthesis from H3PW12O40·nH20 and Ti(OBu)4, simultaneously realizing the load and modification of H3PW12O40. The catalyst was charact... H3PW12O40/TiO2 nanometer photocatalyst was prepared by one step hydrothermal synthesis from H3PW12O40·nH20 and Ti(OBu)4, simultaneously realizing the load and modification of H3PW12O40. The catalyst was characterized by Fourier transform infrared spectroscopy(FTIR), powder X-ray diffraction(XRD), nitrogen adsorp- tion-desorption analysis and scanning electron microscopy(SEM). The results show that the catalyst is Keggin struc- ture and crystallized in anatase structure, the diameter and specific area of the prepared catalyst are 3.8 nm and 177.9 m^2/g, respectively, and its dispersity is better. The photocatalytic properties were compared for TiO2H3PW12O40/TiO2 prepared by impregnation and H3PW12O40/TiO2 prepared by hydrothermal method with methyl orange as a probe. The effects of H3PW12O40 loadings, crystallization method, initial pH and concentration of dye solution on the degradation of methyl orange were investigated. 展开更多
关键词 H3PWt2O40/TiO2 Hydrothermal synthesis Photocatalytic performance DEGRADATION methyl orange
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Photoelectrocatalytic activity of immobilized Yb doped WO3 photocatalyst for degradation of methyl orange dye 被引量:4
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作者 S.V.Mohite V.V.Ganbavle K.Y.Rajpure 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第3期440-447,共8页
Pure WOand Yb:WOthin films have been synthesized by spray pyrolysis technique. Effect of Yb doping concentration on photoelectrochemical, structural, morphological and optical properties of thin films are studied. X-r... Pure WOand Yb:WOthin films have been synthesized by spray pyrolysis technique. Effect of Yb doping concentration on photoelectrochemical, structural, morphological and optical properties of thin films are studied. X-ray diffraction analysis shows that all thin films are polycrystalline nature and exhibit monoclinic crystal structure. The 3 at% Yb:WOfilm shows superior photoelectrochemical(PEC) performance than that of pure WOfilm and it shows maximum photocurrent density(Iph= 1090 μA/cm) having onset potentials around +0.3 V/SCE in 0.01 M HClO. The photoelectrocatalytic process is more effective than that of the photocatalytic process for degradation of methyl orange(MO) dye. Yb doping in WOphotocatalyst is greatly effective to degrade MO dye. The enhancement in photoelectrocatalytic activity is mainly due to the suppressing the recombination rate of photogenerated electron-hole pairs. The mineralization of MO dye in aqueous solution is studied by measuring chemical oxygen demand(COD) values. 展开更多
关键词 DEGRADATION Photocatalytic activity methyl orange dye Thin film Yb doped WO3 Spray pyrolysis technique
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Adsorption Behavior of Methyl Orange onto Modified Ultrafine Coal Powder 被引量:10
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作者 刘转年 周安宁 +1 位作者 王贵荣 赵晓光 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第6期942-948,共7页
The adsorption of methyl orange onto ultrafine coal powder (UCP) and modified ultrafine coal powder (MUCP) from aqueous solutions were studied, in which the influence of contact time, dosage, temperature, pH, and ... The adsorption of methyl orange onto ultrafine coal powder (UCP) and modified ultrafine coal powder (MUCP) from aqueous solutions were studied, in which the influence of contact time, dosage, temperature, pH, and methyl orange concentration in the solution were investigated. The adsorption kinetics of methyl orange by UCP and MUCP can be described by the Lagergren first-order and pseudo second-order kinetic models, respectively. The adsorption isotherms of methyl orange onto MUCP at 303, 313 and 323 K follow the Freundlich and Langmuir isotherm equation. Values of △G^0 for methyl orange adsorption onto MUCP are -22.55, -23.10 and -23.79 kJ·mol^-1 at 303, 313, and 323 K, respectively. The values of △H^0 and △S^0 are -3.74 kJ· mol^-1 and 61.99 J·mol^-1, respectively. The adsorption process is spontaneous and exothermic. 展开更多
关键词 ultrafine coal powder methyl orange ADSORPTION wastewater treatment
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Investigation of Photocatalytic Degradation of Methyl Orange by Using Nano-Sized ZnO Catalysts 被引量:6
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作者 Changchun Chen Jiangfeng Liu +1 位作者 Ping Liu Benhai Yu 《Advances in Chemical Engineering and Science》 2011年第1期9-14,共6页
Nano-sized ZnO catalysts were prepared by a direct precipitation method under the optimal conditions (cal-cination of precursors at 550?C for 120 min). The as-synthesized ZnO catalysts were characterized by X-ray diff... Nano-sized ZnO catalysts were prepared by a direct precipitation method under the optimal conditions (cal-cination of precursors at 550?C for 120 min). The as-synthesized ZnO catalysts were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and UV-Vis spectroscopy. The photocatalytic prop-erties of ZnO nanoparticles were investigated via methyl orange (MO) as a model organic compound under UV light irradiation. The influence of operating parameters on MO degradation including the amount of ZnO catalysts, pH value of solutions, and the photodegradation temperature was thoroughly examined. In addition, the kinetic process of photocatalytic degradation of MO using nano-sized ZnO catalyst was also examined, and the degradation of MO follow the first order kinetics. 展开更多
关键词 ZnO NANOPARTICLES PHOTOCATALYTIC Degradtion methyl ORange
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脓毒症诊治中Ang/Tie信号通路的研究进展
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作者 杨航 戴菁 王学锋 《诊断学理论与实践》 2024年第1期90-95,共6页
脓毒症以及伴随的多器官功能障碍是一组常见的临床综合征,其患病率随着人口老龄化逐年上升。全球每年发生2000万例脓毒症,死亡率为26%。早期准确诊断脓毒症,有利于及时采取针对性的治疗策略,这是降低病死率的关键。内皮细胞是外源病原... 脓毒症以及伴随的多器官功能障碍是一组常见的临床综合征,其患病率随着人口老龄化逐年上升。全球每年发生2000万例脓毒症,死亡率为26%。早期准确诊断脓毒症,有利于及时采取针对性的治疗策略,这是降低病死率的关键。内皮细胞是外源病原体或内源性损伤信号的早期作用对象。研究提示,内皮细胞的结构改变与功能活化在脓毒症的发生、发展中发挥重要作用。作为内皮细胞专属信号通路,血管生成素(angiopoietin,Ang)/酪氨酸激酶受体(tyrosine kinase receptor,Tie)在内皮细胞的异常激活和损伤中发挥重要作用。Ang/Tie信号通路主要包括2种位于内皮细胞中的酪氨酸激酶受体(Tie1、Tie2)和4种分泌性糖蛋白配体(Ang-1、Ang-2、Ang-3、Ang-4)。机制研究方面,Ang-1可持续性激活Tie2受体,维持细胞与细胞、细胞与基质间的相互作用,支持血管内皮细胞正常的生理功能;Ang-2是Ang-1拮抗剂,可竞争性阻断Ang-1与Tie2受体结合。脓毒症环境下,Ang-1下降,Ang-2升高,Ang-1/Ang-2的比值下降。Ang-2竞争性阻断Ang-1与可溶性Tie2受体结合,内皮细胞处于严重异常激活状态。Ang-2介导肝素酶的释放导致糖萼损伤,可引起血管通透性增加;Ang-2可促进炎症反应;Ang/Tie信号系统失调介导凝血功能障碍,Ang-2升高是弥散性血管内凝血的前哨性事件。临床病情监测方面,Ang-2>5.61 ng/mL,诊断脓毒症的灵敏度为74.36%;Ang-2持续升高,提示内皮功能难以恢复,器官发生功能性改变。早期动态监测Ang-2可用于预测脓毒症相关肺损伤、急性肾损伤。Ang-2/Ang-1比值上升、Ang1/可溶性Tie2比值下降可预测脓毒症患者90 d病死率(ROC曲线面积分别为0.787和0.704)。Ang-2和可溶性Tie-2水平下降,则提示脓毒症血浆置换有效。靶向Ang/Tie信号通路的动物实验获得一定成功,但目前临床试验未能获得有价值的结果。脓毒症相关Ang/Tie信号通路有待于进一步深入研究。 展开更多
关键词 脓毒症 血管生成素 酪氨酸激酶受体ang/Tie
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Genome-wide differences in DNA methylation changes in caprine ovaries between oestrous and dioestrous phases 被引量:1
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作者 Xiaopeng An Haidong Ma +3 位作者 Peng Han Chao Zhu Binyun Cao Yueyu Bai 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2019年第1期25-32,共8页
Background: DNA methylation plays a vital role in reproduction.Entire genome DNA methylation changes during the oestrous phase(ES) and dioestrous phase(DS) in the ovaries of Guanzhong dairy goats were investigated usi... Background: DNA methylation plays a vital role in reproduction.Entire genome DNA methylation changes during the oestrous phase(ES) and dioestrous phase(DS) in the ovaries of Guanzhong dairy goats were investigated using bisulphite sequencing to understand the molecular biological mechanisms of these goats' oestrous cycle.Results: We discovered distinct genome-wide DNA methylation patterns in ES and DS ovaries.A total of 26,910 differentially methylated regions were upregulated and 21,453 differentially methylated regions were downregulated in the ES samples compared with the DS samples(P-values ≤0.05 and fold change of methylation ratios ≥2).Differentially methylated region analysis showed hypomethylation in the gene body regions and hypermethylation in the joining region between upstream regions and gene bodies.The methylation ratios of the STAR,FGF2,FGF12,BMP5 and SMAD6 genes in the ES samples were lower than those of the DS samples(P-values≤0.05 and fold change of methylation ratios ≥2).Conversely,the methylation ratios of the EGFR,TGFBR2,IGF2 BP1 and MMD2 genes increased in the ES samples compared with the DS samples.In addition,223 differentially methylated genes were found in the GnRH signalling pathway(KO04912),ovarian steroidogenesis pathway(KO04913),oestrogen signalling pathway(KO04915),oxytocin signalling pathway(KO04921),insulin secretion pathway(KO04911) and MAPK signalling pathway(KO04010).Conclusions: This study is the first large-scale comparison of the high-resolution DNA methylation landscapes of oestrous and dioestrous ovaries from dairy goats.Previous studies and our investigations have shown that the NR5 A2,STAR,FGF2 and BMP5 genes might have potential application value in regulating caprine oestrus. 展开更多
关键词 DIFFERENTIALLY methylated genes Gene ontology Oestrous cycle Pathway
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