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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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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 HIV-1 ENV modification Neutralization assay ELISPOT
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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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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 in... 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 modification Herpes simplex virus type (HSV- 1 Transcriptional regulation
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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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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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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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Successful lifestyle modifications may underlie umbilical cordmesenchymal stromal cell effects in type 2 diabetes mellitus 被引量:1
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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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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
Fatty acid modified glucagon-like peptide-1(7-36) amide was synthesized efficiently on Rink-Amide-MBHA resin by microwave-assisted solid phase method.The method of thermal and controlled microwave irradiation provided... Fatty acid modified glucagon-like peptide-1(7-36) amide was synthesized efficiently on Rink-Amide-MBHA resin by microwave-assisted solid phase method.The method of thermal and controlled microwave irradiation provided impressive enhancements in product yield,selectivity,and reaction rate.The coupling time was dramatically decreased to 6 min,and the desired products were obtained in high yield and purity. 展开更多
关键词 Glucagon-like peptide-1 GLP-1 MICROWAVE Solid phase Fatty acid modification
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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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Fe原位改性小晶粒Silicalite-1分子筛催化醛氨缩合性能研究
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作者 陶金泉 贾亦静 +4 位作者 白天瑜 黄文斌 崔岩 周亚松 魏强 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第9期1280-1289,共10页
吡啶及其衍生物统称为吡啶碱,其广泛应用于农药、医药等领域。Chichibabin醛氨缩合反应是目前工业制取吡啶碱最广泛的路线。目前,使用最广泛的ZSM-5分子筛受制于硅铝骨架结构的不稳定性,高活性反应周期较短(5 h),针对这一问题,本研究选... 吡啶及其衍生物统称为吡啶碱,其广泛应用于农药、医药等领域。Chichibabin醛氨缩合反应是目前工业制取吡啶碱最广泛的路线。目前,使用最广泛的ZSM-5分子筛受制于硅铝骨架结构的不稳定性,高活性反应周期较短(5 h),针对这一问题,本研究选用热稳定性、水热稳定性优异的Silicalite-1分子筛,使用聚乙烯吡咯烷酮(PVP)作为胶体分散剂,在水热合成分子筛的过程中向骨架中引入Fe,结合XRD、SEM、TG、BET、NH3-TPD、Py-FTIR等表征方法探究了晶化条件对Silicalite-1分子筛结晶度、孔结构和酸性质的影响。实验结果表明,在晶种投入量15%、PVP添加量3.75%时产品相对结晶度达到最高(103%),粒径约为200 nm。改性后的Silicalite-1具有更丰富的酸位点,醛氨缩合反应的初始活性由66%增加至85%,在反应进行15 h后,原料转化率和吡啶碱收率分别保持在66%和40%以上。研究提出的原位改性Silicalite-1分子筛策略极大扩宽了纯硅沸石在酸催化领域的应用,具有显著的科研价值和工业化潜力。 展开更多
关键词 Silicalite-1分子筛 原位改性 水热法 催化剂 醛氨缩合反应
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原子转移自由基聚合修饰植物乳杆菌及其对黄曲霉毒素B_(1)吸附脱除作用
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作者 王逸凡 王丙辰 +2 位作者 闫玮璇 何扩 张秀媛 《食品工业科技》 CAS 北大核心 2024年第22期124-130,共7页
为了研究植物乳杆菌材料对黄曲霉毒素去除新方法,为黄曲霉毒素B_(1)的高效生物去除提供了新思路。本文采用基于聚多巴胺的原子转移自由基聚合方法(Polydopamine-based Atom Transfer Radical Polymerization,p-ATRP)和细胞自催化的无铜... 为了研究植物乳杆菌材料对黄曲霉毒素去除新方法,为黄曲霉毒素B_(1)的高效生物去除提供了新思路。本文采用基于聚多巴胺的原子转移自由基聚合方法(Polydopamine-based Atom Transfer Radical Polymerization,p-ATRP)和细胞自催化的无铜添加原子转移自由基聚合方法(Cell-catalyzed Copper-free Atom Transfer Radical Polymerization,c-ATRP)对植物乳杆菌活细胞表面进行修饰,引导原子转移自由基聚合(Atom Transfer Radical Polymerization,ATRP)体系自组装聚合反应形成聚合物材料,对修饰后的植物乳杆菌进行表征,并比较修饰前后植物乳杆菌对黄曲霉毒素B_(1)吸附脱附能力。结果表明,未修饰的植物乳杆菌,细胞表面圆润光滑,经过p-ATRP修饰后的植物乳杆菌,细胞表面变得极为粗糙,经过c-ATRP修饰后的植物乳杆菌,细胞表面出现褶皱;未修饰的植物乳杆菌的Zeta点位为-8.43 mV,经过Dopamine和PNIPAAm修饰后的植物乳杆菌点位分别为1.791和13.767 mV;植物乳杆菌在0.1~100μg/mL黄曲霉毒素B_(1)吸附率为75.3%,p-ATRP和c-ATRP修饰的植物乳杆菌比未修饰的植物乳杆菌吸附能力分别提高了7.8%和6.4%。在相同黄曲霉毒素B_(1)浓度下,植物乳杆菌脱附率为6.1%,p-ATRP和c-ATRP修饰的植物乳杆菌脱附能力分别提高了14.4%和42%。经过修饰后的植物乳杆菌显著提升了植物乳杆菌对黄曲霉毒素的吸附和脱附能力。 展开更多
关键词 原子转移自由基聚合 黄曲霉毒素 B_(1) 植物乳杆菌 细胞表面修饰
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CARM1在恶性肿瘤中的作用与机制研究进展
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作者 刘树义 马泽方 +6 位作者 肖洒雨 高璐 曹明琪 陈子溦 张旭东 李瑜 赵婷婷 《生命科学研究》 CAS 2024年第4期296-304,共9页
共激活蛋白相关的精氨酸甲基转移酶1(coactivator-associated arginine methyltransferase 1,CARM1)是蛋白质精氨酸甲基转移酶(protein arginine methyltransferase,PRMT)家族的成员,又称PRMT4。近年来,CARM1作为一种辅助转录调节因子... 共激活蛋白相关的精氨酸甲基转移酶1(coactivator-associated arginine methyltransferase 1,CARM1)是蛋白质精氨酸甲基转移酶(protein arginine methyltransferase,PRMT)家族的成员,又称PRMT4。近年来,CARM1作为一种辅助转录调节因子已被广泛研究,并被发现在肿瘤、炎性疾病、糖尿病等疾病中具有重要作用。一方面,CARM1通过调节翻译后甲基化修饰参与表观遗传调控,另一方面通过RNA代谢、代谢重编程等形式调控基因表达过程。随着研究的深入,CARM1在恶性肿瘤中的调控作用及分子机制逐步被揭示,但其在不同肿瘤中的调控效应不尽相同,目前需进一步探索其在恶性肿瘤中的调控网络机制。本文就近年来恶性肿瘤中CARM1的作用及其分子机制展开综述,以期为今后的研究提供新思路。 展开更多
关键词 共激活蛋白相关的精氨酸甲基转移酶1(CARM1) 恶性肿瘤 甲基化修饰
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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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HSV1感染中的表观遗传调控机制研究进展 被引量:1
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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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Pancreatic agenesis and altered m6A methylation in the pancreas of PDX1-mutant cynomolgus macaques
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作者 Wen-Hui Zhang Jiong-Han Zhuang +10 位作者 Yun-Yi Guo Xue-Ying Chen Ya-Qing Li Jie-Qiu Xu An-Ran Zhang Bao-Yi Chen Wei Meng Yan-Hua Zhu Jun-Jiu Huang Yong-Long Guo Shi-Hua Yang 《Zoological Research》 SCIE CSCD 2024年第6期1188-1200,共13页
As an essential transcriptional activator,PDX1 plays a crucial role in pancreatic development andβ-cell function.Mutations in the PDX1 gene may lead to type 4 maturityonset diabetes of the young(MODY4)and neonatal di... As an essential transcriptional activator,PDX1 plays a crucial role in pancreatic development andβ-cell function.Mutations in the PDX1 gene may lead to type 4 maturityonset diabetes of the young(MODY4)and neonatal diabetes mellitus.However,the precise mechanisms underlying MODY4 remain elusive due to the paucity of clinical samples and pronounced differences in pancreatic architecture and genomic composition between humans and existing animal models.In this study,three PDX1-mutant cynomolgus macaques were generated using CRISPR/Cas9 technology,all of which succumbed shortly postpartum,exhibiting pancreatic agenesis.Notably,one tri-allelic PDX1-mutant cynomolgus macaque(designated as M4)developed a pancreas,whereas the two monoallelic PDX1-mutant cynomolgus macaques displayed no anatomical evidence of pancreatic formation.RNA sequencing of the M4 pancreas revealed substantial molecular changes in both endocrine and exocrine functions,indicating developmental delay and PDX1haploinsufficiency.A marked change in m6A methylation was identified in the M4 pancreas,confirmed through cultured PDX1-mutantisletorganoids.Notably,overexpression of the m6A modulator METTL3 restored function in heterozygous PDX1-mutant islet organoids.This study highlights a novel role of m6A methylation modification in the progression of MODY4 and provides valuable molecular insights for preclinical research. 展开更多
关键词 PDX1 MODY4 Cynomolgus macaques M6A methylation modification
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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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NASICON型Na_(1+x)Zr_(2)Si_(x)P_(3-x)O_(12)固态电解质及其钠金属电池研究进展
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作者 许希军 林见烽 +2 位作者 罗雄伟 赵经纬 霍延平 《无机盐工业》 CAS CSCD 北大核心 2024年第11期1-14,38,共15页
锂离子电池由于具有较高的工作电压和能量密度实现了商业化。然而,有限的锂资源限制了其广泛应用。钠离子电池展现出与锂离子电池相似的电化学特性,并且钠盐资源更加丰富,因此受到了广泛关注。目前,钠离子电池使用的是有机电解液,这存... 锂离子电池由于具有较高的工作电压和能量密度实现了商业化。然而,有限的锂资源限制了其广泛应用。钠离子电池展现出与锂离子电池相似的电化学特性,并且钠盐资源更加丰富,因此受到了广泛关注。目前,钠离子电池使用的是有机电解液,这存在一系列安全隐患,如漏液和燃烧等,采用固态电解质可以有效解决这些问题。然而,电解质的离子电导率仍有待提升,且材料制备的一致性及与电极间的界面阻抗问题限制了其广泛应用。针对离子电导率的问题,总结分析了不同价态离子取代的影响。针对存在的界面问题,从正极、负极两侧分析了现有Na_(1+x)Zr_(2)Si_(x)P_(3-x)O_(12)电解质的界面改性方法。最后,对Na_(1+x)Zr_(2)Si_(x)P_(3-x)O_(12)电解质的发展方向进行了展望,有望推动固态钠离子电池的发展。 展开更多
关键词 钠离子电池 固态电解质 Na_(1+x)Zr_(2)Si_(x)P_(3-x)O_(12) 离子电导率 界面修饰
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