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Synthesis,characterization,and antioxidant activity of carboxymethyl chitosan derivatives containing sulfonium salt

Journal of Oceanology and Limnology 2022年第1期40卷 284-295页

作者： Xueqi SUN Jingjing ZHANG Yingqi MI qin.miao Wenqiang TAN qin. LI Zhanyong GUO Key Laboratory of Coastal Biology and Bioresource Utilization Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

To improve the solubility and bioactivity of chitosan,a new class of carboxymethyl chitosan derivatives possessing sulfonium salts was successfully designed and synthesized,including Methyl sulfi de carboxymethyl chitosan(MCMCS),Ethyl sulfi de carboxymethyl chitosan(ECMCS),Propyl sulfi de carboxymethyl chitosan(PCMCS),and Butyl sulfi de carboxymethyl chitosan(BCMCS).To determine the structure of the new class of the derivatives,methods of the Fourier transform infrared spectroscopy(FT-IR),^(1)H nuclear magnetic resonance spectrometer(^(1)H NMR),and^(13)C nuclear magnetic resonance spectrometer(^(13)C NMR)were ***,the antioxidant activity of the derivatives for three types of free radicals,i.e.,hydroxyl radical,superoxide radical,and 1,1-diphenyl-2-picrylhydrazyl(DPPH)radical was evaluated in *** addition,the L929 cells were adopted to test the cytotoxicity of chitosan and its derivatives by CCK-8 *** class of the carboxymethyl chitosan derivatives showed a strong scavenging ability against the three free radicals at 1.6 mg/mL,with scavenging rate of over 70%and some up to 100%.At this high rate,the overall cell viability in the toxicity test reached more than 80%,indicating that the synthetic derivative had a little *** results show that the introduction of carboxymethyl group to chitosan increased the water-solubility of chitosan,and the combination of sulfonate ions with diff erent chain lengths further enhanced the antioxidant activity of ***,the sulfonium-containing carboxymethyl chitosan derivatives had excellent bioactivity with good application prospects in food,biomedicine,and medical fi elds.

关键词： antioxidant activity carboxymethyl chitosan derivative sulfonium salts structural characteristics/synthesis

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毛竹PheTCP19b基因可变剪接体对芽发育的影响

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农业生物技术学报 2025年第1期33卷 43-54页

作者：郝琴申孜闫小玲周敏舒郭小勤浙江农林大学竹子研究院/省部共建亚热带森林培育国家重点实验室

可变剪接(alternative splicing, AS)是一种转录后的修饰过程，在生物体各种生理过程中发挥重要作用。TCP是一种植物特有的转录因子，参与植物多种生长发育调控过程。为深入探究毛竹(Phyllostachys edulis) TCP19b基因可变剪接体的表达... 详细信息

可变剪接(alternative splicing, AS)是一种转录后的修饰过程，在生物体各种生理过程中发挥重要作用。TCP是一种植物特有的转录因子，参与植物多种生长发育调控过程。为深入探究毛竹(Phyllostachys edulis) TCP19b基因可变剪接体的表达特性及生物学功能，本研究采用RT-PCR技术克隆了毛竹TCP19b基因全长CDS，采用qRT-PCR技术和GUS组织染色分析了可变剪接体的表达量及表达部位，通过亚细胞定位及遗传转化分析了可变剪接体编码蛋白的定位及生物学功能。结果显示，毛竹PheTCP19b基因发生了可变剪接，产生了2种可变剪接体PheTCP19bα和PheTCP19bβ，分别编码346和382个氨基酸，2种可变剪接体都包含保守的bHLH结构域。PheTCP19b与水稻(Oryza sativa) OsTCP19亲缘关系最近。2个可变剪接体的组织特异性表达模式存在一定差异，PheTCP19bα的组织特异性强，而PheTCP19bβ表现出组成型表达特性，油菜素内酯(brassinolide, BR)可诱导2个可变剪接体的表达。2个可变剪接体蛋白均富集在细胞核。PheTCP19bα和PheTCP19bβ均可以将拟南芥(Arabidopsis thaliana) brc1突变体多分枝表型回补到野生型表型。本研究为进一步探讨PheTCP19b基因不同剪接体在芽发育过程中的分子机制提供了基础资料。

关键词：毛竹 TCP转录因子可变剪接(AS) 芽发育油菜素内酯(BR)

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Master Quorum Sensing Regulator HapR Acts as A Repressor of the Mannitol Phosphotransferase System Operon in Vibrio cholerae

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Biomedical and Environmental Sciences 2022年第1期35卷 69-72页

作者： ZHANG Yi Quan MA Li Zhi GAO Yue qin.qin.LI Jie LOU Jing ZHANG miao miao XUE Xing Fan KAN Biao GAO He Department of Clinical Laboratory Nantong Third Hospital Affiliated to Nantong UniversityNantong 212006JiangsuChina Medical Risk Management Section Third Medical CentreChinese PLA(People’s Liberation Army)General HospitalBeijing 100039China First Affiliated Hospital of Dalian Medical University Dalian 116011LiaoningChina State Key Laboratory of Infectious Disease Prevention and Control National Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China School of Medicine Jiangsu UniversityZhenjiang 212013JiangsuChina

The phosphoenolpyruvate(PEP):carbohydrate phosphotransferase system(PTS)is widely used by bacteria to take up sugars or sugar derivatives;.PTS is usually composed of a histidine protein(HPr),enzyme I(EI),and several e... 详细信息

关键词： sugar system usual

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The effects of autophagy on vascular endothelial cells induced by airborne PM2.5

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Journal of Environmental Sciences 2018年第4期30卷 182-187页

作者： Zhixiang Zhou Tong Shao Mengnan qin.Xiaoyan miao Yu Chang Wang Sheng Fengshang Wu Yunjiang Yu College of Life Science and Bioengineering Beijing University of Technology State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences South China Institute of Environmental Science Ministry of Environmental Protection

The purpose of this study was to examine the direct toxicity of PM2.5 collected from Beijing on human umbilical vein endothelial cells（HUVEC）. A Cell Counting Kit 8（CCK8） assay demonstrated that PM2.5 exposure decreased the proliferation of HUVECs in a dosedependent manner. We also found that PM2.5 exposure induced autophagy in HUVECs, as evidenced by：（1） an increased number of double-membrane vesicles;（2） enhanced conversion and punctuation of the microtubule-associated protein light chain 3（LC3）; and（3） decreased levels of the selective autophagy substrate p62 in a time-dependent ***, promoting autophagy in PM2.5-exposed HUVECs with rapamycin increased the cell survival rate, whereas inhibiting autophagy via 3-methyladenine significantly decreased cell survival. These results demonstrate that PM2.5 exposure can induce cytotoxicity and autophagy in HUVECs and that autophagy play a protective role against PM2.5-induced cytotoxicity. The findings of the present study imply a direct toxic effect of PM2.5 on HUVECs and provide novel insight into the mechanism of cardiovascular diseases caused by PM2.5 exposure.

关键词： PM2.5 HUVEC Cytotoxicity Autophagy

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DNA detection based on Mn-doped ZnS quantum dots/methylene blue nanohybrids

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Chinese Chemical Letters 2016年第5期27卷 773-778页

作者： Yan Li Yan-Ming miao Mao-qin. Yang Yu-Xia Wu Gui-qin.Yan Shanxi Normal University Linfen 041004 China

Nanohybrids were formed from 3-mercaptopropionic acid （MPA）-coated Mn-doped ZnS quantum dots （QDs） and methylene blue （MB） via electrostatic interaction, and then used in the detection of trace DNA. The principle of detection is as follows： MB binds with Mn-doped ZnS QDs via electrostatic interaction, and then quenches the room temperature phosphorescence （RTP） of the QDs through photoinduced electron-transfer （PIET）. After the addition of DNA, MB binds with DNA through intercalation and electrostatic interaction, and desorbs from the surfaces of Mn-doped ZnS QDs, which recovers the RTP of the QDs. On this basis, a DNA detection method based on the properties of RTP was set up. This method shows a detection range of 0.2-20 mg/L, and a detection limit of 0.113 mg/L. Since this method is based on the RTP of QDs, it is not interfered by the background fluorescence or scattering light in vivo, and thus, avoids complex sample pretreatment. Thus, this method is very feasible for detection of trace DNA in biofluids.

关键词： Room temperature phosphorescence Photoinduced electron-transfer DNA Quantum dots Methylene blue

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HMFI分子筛Bronsted酸性位点与碱性分子的作用机制

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原子与分子物理学报 2025年第4期42卷 1-7页

作者：郑健秦康秦玉才宋丽娟中石化石油化工科学研究院有限公司北京100083 辽宁石油化工大学辽宁省石油化工催化科学与技术重点实验室抚顺113001

采用密度泛函理论(DFT)方法,以单铝、双铝和三铝酸性位点HMFI分子筛为模型分子筛,计算去质子化能考察HMFI分子筛的本征酸性,以NH_(3)分子作为模型分子,计算NH_(3)分子在HMFI分子筛中的吸附能与去质子化能进行关联性分析,并进一步考察NH_... 详细信息

采用密度泛函理论(DFT)方法,以单铝、双铝和三铝酸性位点HMFI分子筛为模型分子筛,计算去质子化能考察HMFI分子筛的本征酸性,以NH_(3)分子作为模型分子,计算NH_(3)分子在HMFI分子筛中的吸附能与去质子化能进行关联性分析,并进一步考察NH_(3)分子与HMFI分子筛的作用机制.研究表明分子筛Bronsted酸(简称B酸)强度与B酸数量没有强相关性,在考虑B酸位数量的同时须考虑B酸位的分布.酸性位点数量和分布的差异均可以调控NH_(3)分子的吸附构象,并且可以通过调节HMFI分子筛孔道对分子施加相互作用的模式,解析分子的结构和电子性质,精准调控分子的进一步转化.此项工作可以为未来高效多孔材料有效物种活性位的构建提供新思路.

关键词：密度泛函理论 HMFI分子筛 Bronsted酸性质吸附性能

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含孔洞CoCrNiFeCu高熵合金纳米压入的分子动力学模拟

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原子与分子物理学报 2025年第3期42卷 141-148页

作者：史银花施琴江苏联合职业技术学院镇江分院镇江212016

高熵合金具有优异的力学性能、耐磨耐蚀耐高温等性能,成为未来最有发展潜力的新型材料之一.因此,本文通过分子动力学模拟的方法探究了孔洞对CoCrNiFeCu高熵合金模型纳米压痕力学性能和位错演化的影响.结果表明,屈服点、载荷、杨氏模量... 详细信息

高熵合金具有优异的力学性能、耐磨耐蚀耐高温等性能,成为未来最有发展潜力的新型材料之一.因此,本文通过分子动力学模拟的方法探究了孔洞对CoCrNiFeCu高熵合金模型纳米压痕力学性能和位错演化的影响.结果表明,屈服点、载荷、杨氏模量和硬度等力学参数随着孔洞深度D的增加呈现先增加后稳定的趋势.孔洞的存在显著影响了位错形核的位置,随着孔洞深度的增加,初始位错优先在孔洞与表面之间形成,随后集中在模型表面形成,且位错环由平面圆环状转变为“翼状”.在孔洞深度较小时(D<40A),位错环沿(110)面水平扩展,随着孔洞深度的增加,位错环开始向下扩展.此外,在压痕深度为30?时,位错密度随着孔洞深度的增加逐渐增加.

关键词： CoCrNiFeCu 分子动力学纳米压入力学性能位错演变

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Relationship between copper content of slag and matte in the SKS copper smelting process

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International Journal of Minerals,Metallurgy and Materials 2019年第3期26卷 301-308页

作者： qin.meng Wang Song-song Wang miao Tian Ding-xuan Tang qin.-hua Tian Xue-yi Guo School of Metallurgy and Environment Central South University Hunan Key Laboratory of Nonferrous Metal Resources Recycling School of Mineral Processing and Bioengineering Central South University

In the newly developed oxygen-enriched bottom-blowing copper smelting process(also known as the SKS copper smelting process), Cu loss in slag is one of the most concerning issues. This paper presents our research results concerning the relationship between the Cu content of the matte and slag in the SKS process; the results are based on actual industrial production in the Dongying Fangyuan copper smelter. The results show that the matte grade strongly influences Cu losses in slag. The dissolved and entrained losses account for 10%–20% and 80%–90% of the total SKS industrial Cu losses in slag, respectively. With increasing matte grade, the dissolved and entrained Cu losses in the SKS slag both increase continuously. When the matte grade is greater than 68%, the content of Cu in the smelting slag increases much more dramatically. To obtain a high direct recovery of copper, the matte grade should be less than 75% in industrial SKS copper production.

关键词： copper smelting oxygen-enriched bottom-blowing matte grade Cu loss SKS process

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Study of calf thymus DNA irradiated in vitro with MeV fluorine ions

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Nuclear Science and Techniques 2006年第5期17卷 272-275页

作者： miao Qi LAI Jiang-Nan XUE Jian-Ming qin.Huai-Li WANG Wei-Dong qin.Guang-Yong WANG Yu-Gang Henan Provincial Key Lab of Ionbeam Bioengineering Zhengzhou University Zhengzhou 450052 China Key Laboratory of Heavy Ion Physics Peking University MOE Beijing 100871 China

A study of the fragments of DNA irradiated with MeV ions is important for the understanding of the DNA damage mechanism and the subsequent biological effects (induced by heavy ions). In this experiment, the products of calf thymus DNA (CT DNA) irradiated with MeV fluorine ions were analyzed using agarose gel electrophoresis, modified time-of-flight mass spectrometer (MALDI-TOF), and high-performance liquid chromatography (HPLC). The results showed that the molecular mass of the fragments were concentrated around 831 bp with agarose gel elec- trophoresis, there was no observable product in the range of 1,000 ? 30,000 (m/q) using MALDI-TOF, and small bio- molecules were separated from the products. The results of this study indicated that the strand breaks of calf thymus DNA induced by MeV fluorine ions were nonrandom.

关键词：胸腺DNA 氟离子体外辐照 DNA损伤机制

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Nematode-induced trap formation regulated by the histone H3K4 methyltransferase AoSET1 in the nematode-trapping fungus Arthrobotrys oligospora

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Science China(Life Sciences) 2023年第11期66卷 2663-2679页

作者： Qiao miao Zhengqi Wang Ziyu Yin Xiaoying Liu Ran Li Ke-qin.Zhang Juan Li State Key Laboratory for Conservation and Utilization of Bio-Resources Key Laboratory for Microbial Resources of the Ministry of EducationSchool of Life SciencesYunnan UniversityKunming 650091China

The methylation of lysine 4 of histone H3(H3K4),catalyzed by the histone methyltransferase KMT2/SET1,has been functionally identified in many pathogenic fungi but remains unexplored in nematode-trapping fungi(NTFs).Here,we report a regulatory mechanism of an H3K4-specific SET1 orthologue,AoSET1,in the typical nematode-trapping fungus Arthrobotrys *** the fungus is induced by the nematode,the expression of AoSET1 is *** of AoSet1 led to the abolishment of ***,the yield of traps and conidia ofΔAoSet1 was significantly lower than that of the WT strain,and the growth rate and pathogenicity were also ***,H3K4 trimethylation was enriched mainly in the promoter of two bZip transcription factor genes(AobZip129 and AobZip350)and ultimately up-regulated the expression level of these two transcription factor *** theΔAoSet1 and AoH3K4A strains,the H3^(K4)me modification level was significantly decreased at the promoter of transcription factor genes AobZip129 and *** results suggest that AoSET1-mediated H3KEme serves as an epigenetic marker of the promoter region of the targeted transcription factor ***,we found that AobZip129 negatively regulates the formation of adhesive networks and the pathogenicity of downstream AoPABP1 and *** findings confirm that the epigenetic regulatory mechanism plays a pivotal role in regulating trap formation and pathogenesis in NTFs,and provide novel insights into the mechanisms of interaction between NTFs and nematodes.

关键词： Arthrobotrys oligospora trap formation epigenetic regulatory histone modification pathogenicity

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