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Effect of ultrasonic modification on the protective activity of Flammulina velutipes polysaccharide to prevent ethanol-induced injury on GES-1 cells
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作者 Jinrong Xiao Xin Chen +5 位作者 Jingsi Zhang Yifan Wang Lei Zhong Qiping Zhan Qiuhui Hu Liyan Zhao 《Food Science and Human Wellness》 SCIE CSCD 2023年第6期2451-2459,共9页
Flammulina velutipes(F.velutipes)polysaccharides were modified by ultrasound at the rated power of 150 W and 900 W.The monosaccharide composition,ultraviolet-visible,and Fourier transform infrared spectral characteris... Flammulina velutipes(F.velutipes)polysaccharides were modified by ultrasound at the rated power of 150 W and 900 W.The monosaccharide composition,ultraviolet-visible,and Fourier transform infrared spectral characteristics of F.velutipes polysaccharides(FVP)and their ultrasonic modification products(U-FVPs)were determined.The protective effects of FVP and U-FVPs on human gastric mucosal cells GES-1 were confi rmed for the first time.The mole ratios of glucose and galactose were decreased and the mole ratio of mannose was increased after ultrasonic modification.Compared with the original FVP and the FVP modifi ed by ultrasound of 150 W(U-FVP1),the FVP modifi ed by ultrasound of 900 W(U-FVP2)could better prevent ethanol-induced damage to GES-1 cells.With increasing ultrasound intensity,the protective effect of FVPs on GES-1 cells was significantly enhanced by more effective prevention of intracellular reactive oxygen species(ROS)production and more promotion of expression of triglyceride factor 2(TFF2),prostaglandin E2(PGE2),epidermal growth factor(EGF),and transforming growth factorβ1(TGF-β1)mRNA.The ultrasonic modifi cation might be an effective way to develop novel F.velutipes polysaccharides that could effectively resist the gastric injury caused by excessive alcohol consumption. 展开更多
关键词 Flammulina velutipes polysaccharide Ultrasonic modification GES-1 cell Gastric ulcer Ethanol-induced injury
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骨形成肽1和聚多巴胺复合涂层修饰提高聚醚醚酮表面活性
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作者 秦敬杰 郭子歌 +3 位作者 李睿 马士卿 卢瑞杰 李梦君 《中国组织工程研究》 CAS 北大核心 2025年第16期3318-3325,共8页
背景:聚醚醚酮具有与人体皮质骨相近的弹性模量及良好的射线透射性、化学稳定性和生物相容性等优点,有望应用于口腔种植领域,然而其具有生物惰性,难以与周围组织形成骨结合,因此如何提高聚醚醚酮的表面活性是目前的主要问题。目的:分析... 背景:聚醚醚酮具有与人体皮质骨相近的弹性模量及良好的射线透射性、化学稳定性和生物相容性等优点,有望应用于口腔种植领域,然而其具有生物惰性,难以与周围组织形成骨结合,因此如何提高聚醚醚酮的表面活性是目前的主要问题。目的:分析聚醚醚酮表面骨形成肽1和聚多巴胺复合涂层的促成骨和成血管作用。方法:将聚醚醚酮片浸泡于多巴胺溶液中24 h,制备聚醚醚酮-聚多巴胺材料;将聚醚醚酮-聚多巴胺材料浸泡于骨形成肽1溶液中24 h,制备聚醚醚酮-聚多巴胺-骨形成肽1材料,表征材料的微观形貌、亲水性与元素组成。将骨髓间充质干细胞分别接种于聚醚醚酮、聚醚醚酮-聚多巴胺、聚醚醚酮-聚多巴胺-骨形成肽1材料表面,通过活死细胞染色和细胞骨架染色评估细胞活性与黏附状态,茜素红和骨钙素免疫荧光染色检测细胞成骨分化能力。将人脐静脉内皮细胞分别接种于3组材料表面,通过活死细胞染色和细胞骨架/血管内皮生长因子免疫荧光染色评估细胞活性及成血管水平。结果与结论:①扫描电镜下可见聚醚醚酮材料表面光滑,聚醚醚酮-聚多巴胺材料表面出现凹凸不平的沉积物,聚醚醚酮-聚多巴胺-骨形成肽1材料表面有小颗粒突起;接触角测试结果显示,聚醚醚酮-聚多巴胺-骨形成肽1材料的亲水性优于其他两种材料;X射线光电子能谱测试结果显示,骨形成肽1成功修饰于聚醚醚酮材料表面;②活死细胞染色和细胞骨架染色显示,相较于其他两种材料,聚醚醚酮-聚多巴胺-骨形成肽1材料可提高骨髓间充质干细胞的活性与黏附;茜素红和骨钙素免疫荧光染色显示,相较于其他两种材料,聚醚醚酮-聚多巴胺-骨形成肽1材料可促进骨髓间充质干细胞的成骨分化;③活死细胞染色和免疫荧光染色显示,相较于其他两种材料,聚醚醚酮-聚多巴胺-骨形成肽1材料可提高人脐静脉内皮细胞的活性与黏附及血管内皮生长因子蛋白的表达;④结果表明,骨形成肽1和聚多巴胺复合涂层可提高聚醚醚酮表面的促成骨和成血管活性。 展开更多
关键词 聚醚醚酮 表面改性 聚多巴胺 涂层 骨形成肽1 成骨分化 成血管
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N^(6)-腺苷甲基化修饰及其对LINE-1的调控机制
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作者 张傲 岑山 李晓宇 《遗传》 CAS CSCD 北大核心 2024年第3期209-218,共10页
长散布元件-1(long interspersed elements-1,LINE-1)是现今在人类基因组中唯一具有自主转座能力的转座子,其转座会引起细胞基因组结构和功能的改变,是导致多种严重疾病的重要因素。在转座过程中,LINE-1 mRNA是转座中间体的核心,宿主细... 长散布元件-1(long interspersed elements-1,LINE-1)是现今在人类基因组中唯一具有自主转座能力的转座子,其转座会引起细胞基因组结构和功能的改变,是导致多种严重疾病的重要因素。在转座过程中,LINE-1 mRNA是转座中间体的核心,宿主细胞对其进行相关修饰直接影响转座。N^(6)-腺苷甲基化修饰(m^(6)A)是真核细胞RNA上最丰富且动态可逆的表观遗传修饰。目前发现m^(6)A修饰也存在于LINE-1 mRNA上,参与LINE-1整个生命周期的调控,影响其转座和基因组中LINE-1相邻基因的表达,进而影响基因组稳定性、细胞自我更新与分化潜能,在人类发育和疾病中具有重要作用。本文介绍了LINE-1 m^(6)A修饰的位置、功能以及相关机制,并总结了LINE-1的m^(6)A修饰对其转座调控的研究进展,以期为相关疾病发生发展的机制研究和治疗提供新的思路。 展开更多
关键词 m^(6)A修饰 逆转录转座子 LINE-1 基因组 基因组稳定性
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Successful lifestyle modifications may underlie umbilical cordmesenchymal stromal cell effects in type 2 diabetes mellitus
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作者 Alexandra Papadopoulou Konstantinos I Papadopoulos 《World Journal of Diabetes》 SCIE 2023年第3期347-351,共5页
Type 2 diabetes mellitus(T2DM)is a lifelong condition and a grave threat to human health.Innovative efforts to relieve its detrimental effects are acutely needed.The sine qua non in T2DM management is consistent adher... Type 2 diabetes mellitus(T2DM)is a lifelong condition and a grave threat to human health.Innovative efforts to relieve its detrimental effects are acutely needed.The sine qua non in T2DM management is consistent adherence to a prudent lifestyle and nutrition,combined with aerobic and resistance exercise regimens,together repeatedly shown to lead to complete reversal and even longterm remission.Non-adherence to the above lifestyle adjustments condemns any treatment effort and ultimately the patient to a grim fate.It is thus imperative that every study evaluating the effects of innovative interventions in T2DM objectively compares the novel treatment modality to lifestyle modifications,preferably through double-blind controlled randomization,before claiming efficacy. 展开更多
关键词 Type 1 diabetes mellitus Type 2 diabetes mellitus Human umbilical cord mesenchymal stem cells Diabetes remission Diabetes reversal Lifestyle modifications
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TS-1分子筛研究进程及催化应用
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作者 杨帆 王怡明 +2 位作者 朱韩英 蒋旭 史晓波 《工业催化》 CAS 2024年第3期29-34,共6页
TS-1是一类独特的用于液相选择性氧化反应的分子筛催化剂,在高结晶沸石框架中具有四面体配位Ti^(4+)离子。TS-1/H_(2)O_(2)绿色反应体系已经取得了相当大的突破。TS-1分子筛的催化性能与其拓扑结构、晶体形态、四面体Ti的含量和反应微... TS-1是一类独特的用于液相选择性氧化反应的分子筛催化剂,在高结晶沸石框架中具有四面体配位Ti^(4+)离子。TS-1/H_(2)O_(2)绿色反应体系已经取得了相当大的突破。TS-1分子筛的催化性能与其拓扑结构、晶体形态、四面体Ti的含量和反应微环境有关。当前石油化工和精细化工等行业对大分子氧化催化剂的需求日益增长,开发催化性能显著提高的新型TS-1的研究成为热点。综述TS-1分子筛近年的研究进展及催化应用。 展开更多
关键词 催化剂工程 TS-1分子筛 骨架钛 选择性氧化 反应晶化 化学改性
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Comparison of the Immunogenicities of HIV-1 Mutants Based on Structural Modification of env 被引量:1
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作者 Jian-hui NIE Chun-tao ZHANG +6 位作者 Hui-hui CHONG Xue-ling WU Chun-yu LIU Yu WU Chen-yan ZHAO Lin-qi ZHANG You-chun WANG 《Virologica Sinica》 SCIE CAS CSCD 2008年第4期233-246,共14页
Eleven env mutants were designed and generated by site-directed mutagenesis of the regions around NAb epitopes and deletions of variable regions in env. The immunogenicities of the generated mutants were evaluated usi... Eleven env mutants were designed and generated by site-directed mutagenesis of the regions around NAb epitopes and deletions of variable regions in env. The immunogenicities of the generated mutants were evaluated using single-cycle infection neutralization assays with two pseudoviruses and IFN-γ ELISPOT. Overall, five mutants (dWt, M2, M5-2, M5-1 and dM7) induced higher neutralization activities for both pseudoviruses than plasmid Wt, while only two of the mutants (dWt and M5-2) showed significant differences (P<0.05). Two mutants (M2 and dM2) induced more Env-specific T cells than plasmid Wt. Statistically however, significance was only reached for mutant M2. Thus, properly modified HIV-1 Env may have the potential to induce potent cellular and humoral immune responses. 展开更多
关键词 人体免疫缺损病毒 艾滋病 中和化验 突变异种
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A Novel β-1,4-N, 6-O-Diacetylmuramidase from Streptomyces griseus and its Chemical Modification
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作者 Chang Kui SUN Yu Zhen ZHANG Ming CHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第11期1469-1472,共4页
A novel lysozyme named β-1, 4-N, 6-O-diacetylmuramidase R2 was purified and characterized from Streptomyces griseus. The molecular weight of the enzyme was determined by MALDI-TOF-MS as 23.5 kDa. The N-terminal amino... A novel lysozyme named β-1, 4-N, 6-O-diacetylmuramidase R2 was purified and characterized from Streptomyces griseus. The molecular weight of the enzyme was determined by MALDI-TOF-MS as 23.5 kDa. The N-terminal amino acid sequence was DTSGVQGIDVSHWQG. Chemical modification of β-1, 4-N, 6-O-diacetylmuramidase R2 indicated that sulfhydryl group and carbamidine of arginine residues are not essential for the activity of the enzyme, but lysine residues and imidazole of histidine residues are essential for the activity. The number of essential tryptophan and carboxyl groups was found that only one tryptophan residue and three carboxyl groups in the active site. 展开更多
关键词 Chemical modification β-1 4-N 6-O-diacetylmuramidase lysozyme.
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XPS STUDIES ON SURFACE MODIFIED POLY [1-(TRIMETHYLSILYL)-1-PROPYNE] MEMBRANES Ⅱ SURFACE MODIFICATION BY BROMINE VAPOR
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作者 许观藩 孙晓光 +2 位作者 邱雪鹏 张金兰 郑国栋 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1994年第2期180-184,共5页
Surface modification of poly [1-(trimethylsilyl)-1-propyne] (PTMSP) membranes bybromine vapor has been studied. It is shown that Br/C atomic ratio at the surfaces increased withthe time of bromination until about 60 m... Surface modification of poly [1-(trimethylsilyl)-1-propyne] (PTMSP) membranes bybromine vapor has been studied. It is shown that Br/C atomic ratio at the surfaces increased withthe time of bromination until about 60 min, then it reached a plateau. The results of XPS and IRstudies indicated that the addition of bromine to double bonds and the replacement of H on CH_3 bybromine had taken place so that a new peak at 286.0 eV (C--Br)in C_(1s) spectra and some newbands, e. g. at 1220 and 580cm^(-1) in IR spectra were formed. The fact,t Po_2, permeability ofoxygen, decreased and α_(O_2/N_2), separation factor of oxygen relative to nitrogen, increased withbromination time, shows that surface modification of PTMSP by bromine may be an efficient approach to prepare PTMSP membranes used for practical gas separations. 展开更多
关键词 Membrane Poly [1-(trimethylsilyl)-1-propyne] Bromination 3 Surface modification XPS
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Long non-coding RNA GATA6-AS1 is mediated by N6-methyladenosine methylation and inhibits the proliferation and metastasis of gastric cancer
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作者 Jun-Jie Shen Min-Chang Li +1 位作者 Shao-Qi Tian Wen-Ming Chen 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期1019-1028,共10页
BACKGROUND Through experimental research on the biological function of GATA6-AS1,it was confirmed that GATA6-AS1 can inhibit the proliferation,invasion,and migration of gastric cancer cells,suggesting that GATA6-AS1 p... BACKGROUND Through experimental research on the biological function of GATA6-AS1,it was confirmed that GATA6-AS1 can inhibit the proliferation,invasion,and migration of gastric cancer cells,suggesting that GATA6-AS1 plays a role as an anti-oncogene in the occurrence and development of gastric cancer.Further experi-ments confirmed that the overexpression of fat mass and obesity-associated protein(FTO)inhibited the expression of GATA6-AS1,thereby promoting the occurrence and development of gastric cancer.AIM To investigate the effects of GATA6-AS1 on the proliferation,invasion and migration of gastric cancer cells and its mechanism of action.METHODS We used bioinformatics methods to analyze the Cancer Genome Atlas(https://portal.gdc.cancer.gov/.The Cancer Genome Atlas)and download expression data for GATA6-AS1 in gastric cancer tissue and normal tissue.We also constructed a GATA6-AS1 lentivirus overexpression vector which was transfected into gastric cancer cells to investigate its effects on proliferation,migration and invasion,and thereby clarify the expression of GATA6-AS1 in gastric cancer and its biological role in the genesis and development of gastric cancer.Next,we used a database(http://starbase.sysu.edu.cn/starbase2/)to analysis GATA6-AS1 whether by m6A methylation modify regulation and predict the methyltransferases that may methylate GATA6-AS1.Furthermore,RNA immunoprecipitation experiments confirmed that GATA6-AS1 was able to bind to the m6A methylation modification enzyme.These data allowed us to clarify the ability of m6A methylase to influence the action of GATA6-AS1 and its role in the occurrence and development of gastric cancer.RESULTS Low expression levels of GATA6-AS1 were detected in gastric cancer.We also determined the effects of GATA6-AS1 overexpression on the biological function of gastric cancer cells.GATA6-AS1 had strong binding ability with the m6A demethylase FTO,which was expressed at high levels in gastric cancer and negatively correlated with the expression of GATA6-AS1.Following transfection with siRNA to knock down the expression of FTO,the expression levels of GATA6-AS1 were up-regulated.Finally,the proliferation,migration and invasion of gastric cancer cells were all inhibited following the knockdown of FTO expression.CONCLUSION During the occurrence and development of gastric cancer,the overexpression of FTO may inhibit the expression of GATA6-AS1,thus promoting the proliferation and metastasis of gastric cancer. 展开更多
关键词 Long non-coding RNA GATA6-AS1 N6-methyladenine modification Fat mass and obesity-associated protein Gastric cancer
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Multiplex modification with rare earth elements and P for hypereutectic A1-Si alloys
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作者 OUYANG Zhi-ying MAO Xie-min HONG Mei 《Journal of Shanghai University(English Edition)》 CAS 2007年第4期400-402,共3页
The effect of rare earth (RE) elements on the morphologies and sizes of Si phases in the hypereutectic A1-Si alloys modified with P was investigated. The results show that the addition of La element to the hypereute... The effect of rare earth (RE) elements on the morphologies and sizes of Si phases in the hypereutectic A1-Si alloys modified with P was investigated. The results show that the addition of La element to the hypereutectic A1-Si alloys can enhance the effect of P element on the modification of the primary Si phases. In the multiplex modification of RE-P, the primary Si phase is refiner and the shape of the eutectic Si is changed from long needle-like to short rod-like. Moreover, the agglomeration rate of the primary Si phase is slowed greatly. Even the melt is held for 6 h, the average size of the primary Si phase is still satisfied. The results analyzed by scanning electron microscope (SEM) indicate that La is richer at A1-Si interface than that in α-A1 or primary Si phase. The higher the La content in the A1-Si interface, the smaller the primary Si phase. 展开更多
关键词 multiplex modification hypereutectic A1-Si alloys rare earth elements P.
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Molecular Modification of a HSV-1 Protein and Its Associated Gene Transcriptional Regulation
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作者 Yan-chun CHE Li JIANG Qi-han LI 《Virologica Sinica》 SCIE CAS CSCD 2008年第6期394-398,共5页
The molecular modifications of Herpes Simplex Virus Type Ⅰ (HSV-1) proteins represented by acetylation and phosphorylation are essential to its biological functions. The cellular chromatin-remodeling/assembly is invo... The molecular modifications of Herpes Simplex Virus Type Ⅰ (HSV-1) proteins represented by acetylation and phosphorylation are essential to its biological functions. The cellular chromatin-remodeling/assembly is involved in HSV-1 associated gene transcriptional regulation in human cells harboring HSV-1 lytic or latent infections. Further investigation on these biological events would provide a better understanding of the mechanisms of HSV-1 viral gene transcriptional regulation. 展开更多
关键词 分子修饰 HSV-1 蛋白质 基因转录 调控方法
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HSV1感染中的表观遗传调控机制研究进展
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作者 吴长静 邹雨芳 黄新伟 《昆明医科大学学报》 CAS 2024年第1期172-178,共7页
1型单纯疱疹病毒(HSV1)是一类最为常见的人类传染病原体,感染后可导致一系列程度不同的疾病。HSV1在中枢神经系统的潜伏感染及偶发重激活是其病理发生的关键,也为抗病毒治疗带来了巨大的挑战。目前,关于HSV1感染的建立、维持和重激活的... 1型单纯疱疹病毒(HSV1)是一类最为常见的人类传染病原体,感染后可导致一系列程度不同的疾病。HSV1在中枢神经系统的潜伏感染及偶发重激活是其病理发生的关键,也为抗病毒治疗带来了巨大的挑战。目前,关于HSV1感染的建立、维持和重激活的机制并未完全阐明,但普遍认为表观遗传调控可能在其中扮演重要作用。越来越多研究表明,病毒裂解期和潜伏感染期的基因组呈现不同的染色质结构,其富含的多种翻译后修饰组蛋白赋予病毒基因转录激活或抑制特征。此外,病毒潜伏相关转录本LATs也可能参与基因组表观遗传修饰调控。 展开更多
关键词 Ⅰ型单纯疱疹病毒 潜伏相关转录本 表观遗传调控 组蛋白翻译后修饰
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METTL3介导的PDK1 mRNA m^(6)A修饰通过Akt/mTOR信号通路促进肺上皮细胞增殖
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作者 靳艾 李梦宇 孙青竹 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2024年第7期934-946,共13页
腺苷N6-位点甲基化(m^(6)A)在细胞增殖过程中发挥重要作用。RNA甲基转移酶3(METTL3)作为催化m^(6)A关键酶,其介导m^(6)A修饰在肺上皮细胞增殖中的作用机制尚不明确。本研究旨在探讨METTL3介导m^(6)A修饰调控肺上皮细胞增殖的效应及机制... 腺苷N6-位点甲基化(m^(6)A)在细胞增殖过程中发挥重要作用。RNA甲基转移酶3(METTL3)作为催化m^(6)A关键酶,其介导m^(6)A修饰在肺上皮细胞增殖中的作用机制尚不明确。本研究旨在探讨METTL3介导m^(6)A修饰调控肺上皮细胞增殖的效应及机制。结果显示,在肺上皮细胞中敲低METTL 3显著抑制细胞生长,而过表达METTL3则促进了细胞增殖(P<0.05)。进一步的蛋白质免疫印迹结果显示,细胞生长和增殖的关键蛋白质PCNA在METTL 3敲降的肺上皮细胞中蛋白质水平的表达显著下调,并且Akt以及mTOR的磷酸化水平显著降低(P<0.05)。细胞免疫荧光结果发现,METTL 3敲降的肺上皮细胞中m^(6)A修饰水平显著降低(P<0.05)。实时荧光定量PCR及蛋白质免疫印迹结果表明,Akt-mTOR信号通路上游调控分子PDK1的mRNA和蛋白质表达水平在METTL 3敲降的肺上皮细胞中显著下降(P<0.05)。机制上,m^(6)A-IP-qPCR和RIP-qPCR结果进一步表明,METTL3催化PDK 1 mRNA的3′UTR区域m^(6)A修饰,进而被YTH N6-甲基腺苷RNA结合蛋白1(YTHDF1)识别,增强其mRNA的稳定性。总之,本研究揭示了METTL3通过增强PDK1 m^(6)A修饰,进而激活Akt-mTOR信号通路,促进细胞增殖。本研究为METTL3在上皮细胞增殖中的新角色提供了证据,同时为治疗肺上皮细胞损伤修复提供了新的治疗靶点。 展开更多
关键词 甲基转移酶3 RNA m^(6)A修饰 细胞增殖 肺上皮细胞 磷酸肌醇依赖性蛋白激酶-1
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TS-1光催化剂的制备及应用研究进展
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作者 严群 马梦霞 +3 位作者 延旭 毛艳丽 康海彦 宋忠贤 《合成化学》 CAS 2023年第10期806-817,共12页
钛硅分子筛(TS-1)因具有优异的吸附能力、高选择性的催化活性中心和良好的稳定性而成为一类具有应用潜力的光催化材料。然而,其活性仍受限于电荷分离较低和光吸收不足。在众多光催化剂改性方法中,构建异质光催化体系具有简单可行、形式... 钛硅分子筛(TS-1)因具有优异的吸附能力、高选择性的催化活性中心和良好的稳定性而成为一类具有应用潜力的光催化材料。然而,其活性仍受限于电荷分离较低和光吸收不足。在众多光催化剂改性方法中,构建异质光催化体系具有简单可行、形式多样和性能突出等优点,在能源环境方面具有广阔的应用前景。本文总结了TS-1的制备方法、提出了与碳材料偶联、金属/非金属掺杂、贵金属负载和与半导体异质复合4种策略来TS-1光催化活性,分析了TS-1异质光催化剂在水分解制氢、CO 2还原和污染物的降解应用方面的研究现状。 展开更多
关键词 TS-1 光催化 改性 异质结 制氢 二氧化碳还原 降解
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Preparation of phosphorus-modified PITQ-13 catalysts and their performance in 1-butene catalytic cracking 被引量:6
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作者 Penghui Zeng Yun Liang +5 位作者 Shengfu Ji Baojian Shen Honghai Liu Baojie Wang Hongjuan Zhao Mingfu Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第2期193-200,共8页
A series of phosphorus-modified PITQ-13 catalysts was prepared by wet impregnation of NH4H2PO4 solution into an HITQ-13 parent. The catalysts were characterized using XRD, N2 adsorption, MAS NMR and NH3-TPD. Their cat... A series of phosphorus-modified PITQ-13 catalysts was prepared by wet impregnation of NH4H2PO4 solution into an HITQ-13 parent. The catalysts were characterized using XRD, N2 adsorption, MAS NMR and NH3-TPD. Their catalytic performance in 1-butene catalytic cracking was evaluated in a fixed fluidized bed reactor. The results showed that the crystallinity, surface area and pore volume of P-modified PITQ-13 catalysts decreased with the increasing amounts of P. The number of weak acid sites increased, whereas that of strong acidity decreased. The selectivity to propylene in 1-butene cracking reactions increased because of the decrease in strong acidity. The yield of propylene achieved 41.6% over PITQ-13-2 catalyst with a P content of 1.0 wt%, which was 5.1% greater than that achieved over HITQ-13 catalyst. 展开更多
关键词 ITQ-13 ZEOLITE PHOSPHORUS modification 1-BUTENE CRACKING
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Structural Characterization and Chemical Modification of a Glucan from Spores of Ganoderma lucidum 被引量:2
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作者 Bao, XF Fang, JN 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第11期967-970,共4页
A linear alpha -D-(1-->3)-glucan, named PSG, was obtained from the spores of Ganoderma lucidum. The synthesis of positively and negatively charged polyelectrolytes from PSG was developed. Amine groups and carboxyme... A linear alpha -D-(1-->3)-glucan, named PSG, was obtained from the spores of Ganoderma lucidum. The synthesis of positively and negatively charged polyelectrolytes from PSG was developed. Amine groups and carboxymethyl groups were introduced through nucleophilic substitution with 3-chloropropylamine or chloroacetic acid, respectively, Reaction conditions were varied to obtain insight into the influence of variables on the degree of substitution. 展开更多
关键词 alpha-D-(1 -> 3)-glucan chemical modification aminopropylation CARBOXYMETHYLATION
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补阳还五汤对Cav-1^(-/-)小鼠脑缺血后m^(6)A修饰和血管新生的影响 被引量:6
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作者 徐雅倩 陈博威 +3 位作者 田丰铭 刘英飞 易健 刘柏炎 《中国中医药信息杂志》 CAS CSCD 2023年第7期68-73,共6页
目的观察补阳还五汤对小窝蛋白1基因敲除(Cav-1^(-/-))小鼠脑缺血后N6-甲基腺苷(m^(6)A)修饰和血管新生的影响,探讨其可能的作用机制。方法将72只雄性野生型(WT)小鼠及Cav-1^(-/-)(KO)小鼠分别随机分为对照组、模型组和补阳还五汤组,采... 目的观察补阳还五汤对小窝蛋白1基因敲除(Cav-1^(-/-))小鼠脑缺血后N6-甲基腺苷(m^(6)A)修饰和血管新生的影响,探讨其可能的作用机制。方法将72只雄性野生型(WT)小鼠及Cav-1^(-/-)(KO)小鼠分别随机分为对照组、模型组和补阳还五汤组,采用大脑中动脉栓塞法制备脑缺血模型,补阳还五汤组予补阳还五汤(18.5 g/kg)灌胃,对照组和模型组予等体积蒸馏水灌胃,连续7 d。对小鼠进行神经行为学评分,试剂盒检测缺血侧皮质m^(6)A水平,HE染色观察缺血侧皮质病理变化,免疫荧光双标法检测缺血侧皮质血管新生情况,RT-qPCR检测缺血侧皮质甲基转移酶样3(METTL3)、甲基转移酶样14(METTL14)、肾母细胞瘤1相关蛋白(WTAP)、肥胖相关蛋白(FTO)及AlkB同系物5(ALKBH5)mRNA表达。结果与同基因型对照组比较,WT、KO模型组小鼠神经行为学评分及缺血侧皮质m^(6)A水平明显升高(P<0.01),缺血侧皮质出现病理形态损伤,血管性血友病因子(VWF)/Ki-67双标阳性细胞数明显增加(P<0.01),KO模型组小鼠缺血侧皮质WTAP mRNA表达明显升高(P<0.01),FTO和ALKBH5 mRNA表达明显下降(P<0.01);与同基因型模型组比较,WT、KO补阳还五汤组小鼠神经行为学评分及m^(6)A水平明显降低(P<0.01,P<0.05),缺血侧皮质病理形态损伤改善,VWF/Ki-67双标阳性细胞数目明显增加(P<0.05),KO补阳还五汤组小鼠缺血侧皮质WTAP mRNA表达明显降低(P<0.01),FTO和ALKBH5 mRNA表达明显升高(P<0.01,P<0.05)。WT模型组和WT补阳还五汤组各项指标优于KO组(P<0.01,P<0.05)。结论补阳还五汤可能通过Cav-1调控脑缺血小鼠m^(6)A修饰和血管新生,从而发挥保护脑缺血损伤作用。 展开更多
关键词 补阳还五汤 脑缺血 Cav-1^(-/-) m^(6)A修饰 血管新生 小鼠
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PD-L1表达及其调控在肿瘤治疗中作用的研究进展 被引量:2
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作者 陈洪丞成 张宏权 魏潇凡 《生理科学进展》 CAS 2023年第6期526-532,共7页
程序性死亡蛋白1(programmed cell death 1,PD-1)及其配体PD-L1(programmed death 1 ligand 1)是重要的免疫检查点,二者相互作用可负性调节效应T细胞活化与增殖,也是肿瘤细胞逃避免疫监视的重要途径。阻断PD-1与PD-L1的结合,可以解除肿... 程序性死亡蛋白1(programmed cell death 1,PD-1)及其配体PD-L1(programmed death 1 ligand 1)是重要的免疫检查点,二者相互作用可负性调节效应T细胞活化与增殖,也是肿瘤细胞逃避免疫监视的重要途径。阻断PD-1与PD-L1的结合,可以解除肿瘤细胞或抗原提呈细胞对T细胞的抑制,恢复其对肿瘤细胞的识别和杀伤能力。然而,PD-L1的表达受到复杂的调控且在不同的肿瘤中呈现出差异,其主要发生在遗传、转录和转录后水平。本综述介绍PD-L1表达的调控过程及其在肿瘤免疫治疗中的作用,结合这些调控机制实现对不同特征肿瘤进行精准免疫治疗是下一步研究的重点,在肿瘤治疗中具有重要意义。 展开更多
关键词 免疫检查点 PD-1 PD-L1 表达调控 翻译后修饰
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Solid phase synthesis of fatty acid modified glucagon-like peptide-1(7-36) amide under thermal and controlled microwave irradiation
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作者 Ni, Shuai Han Zhang, Hui Bin +2 位作者 Huang, Wen Long Zhou, Jin Pei Qian, Hai 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第1期27-30,共4页
关键词 Glucagon-like peptide-1 GLP-1 MICROWAVE Solid phase Fatty acid modification
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一贯煎通过调节Parp-1的翻译后修饰保护肝细胞DNA
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作者 张宇佳 叶杰 +3 位作者 卢艳琳 闫晓风 李华 王晓玲 《中国药理学通报》 CAS CSCD 北大核心 2023年第2期373-379,共7页
目的观察一贯煎(Yiguanjian decoction,YGJ)影响Parp-1修复H_(2)O_(2)诱导肝细胞DNA损伤的机制。方法培养小鼠胚胎肝细胞BNL CL.2,建立H_(2)O_(2)细胞损伤模型并用YGJ预处理,CCK-8检测细胞活力,Annexin V/PI流式细胞术检测细胞死亡,EDU... 目的观察一贯煎(Yiguanjian decoction,YGJ)影响Parp-1修复H_(2)O_(2)诱导肝细胞DNA损伤的机制。方法培养小鼠胚胎肝细胞BNL CL.2,建立H_(2)O_(2)细胞损伤模型并用YGJ预处理,CCK-8检测细胞活力,Annexin V/PI流式细胞术检测细胞死亡,EDU掺入检测细胞增殖,8-羟基脱氧鸟苷比色法和γ-H_(2)AX细胞荧光染色检测DNA损伤。免疫印迹法检测Parp-1、Parp-1的Par化和乙酰化。结果H_(2)O_(2)作用后,肝细胞凋亡率增加;细胞增殖被明显抑制;DNA损伤持续存在于整个实验过程。Parp-1在6 h升高后维持高表达,Parp-1的Par化和乙酰化均先升高随后降低。Sirt-1的抑制剂EX527可明显提高Parp-1的Par化,而其激动剂SRT1720可明显降低Parp-1的Par化。YGJ作用后细胞凋亡率和DNA损伤明显减少,增殖细胞数明显增加,Parp-1高表达时间点提前,Parp-1的Par化明显提高,乙酰化时间点推迟,且持续时间更长。结论YGJ可降低H_(2)O_(2)诱导的肝细胞DNA损伤,其作用机制与Sirt-1对Parp-1去乙酰化维持其含量、负调控Parp-1的Par化维持一定的活性有关。 展开更多
关键词 肝细胞 PARP-1 Sirt-1 翻译后修饰 DNA损伤 H_(2)O_(2)
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