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StraPep: a structure database of bioactive peptides

DATABASE-THE JOURNAL OF BIOLOGICAL DATABASES AND CURATION 2018年第2018期2018卷 1-N.PAG页

作者： Wang, Jian Yin, Tailang Xiao, xuwen He, Dan Xue, Zhidong Jiang, Xinnong Wang, yan Huazhong Univ Sci & Technol Coll Life Sci & Technol Key Lab Mol Biophys Minist Educ Wuhan 430074 Hubei Peoples R China Wuhan Univ Renmin Hosp Reprod Med Ctr Wuhan 430060 Hubei Peoples R China Huazhong Univ Sci & Technol Sch Software Engn Wuhan 430074 Hubei Peoples R China Sun Yat Sen Univ Affiliated Hosp 1 Dept Neurol Guangzhou 510080 Guangdong Peoples R China

Bioactive peptides, with a variety of biological activities and wide distribution in nature, have attracted great research interest in biological and medical fields, especially in pharmaceutical industry. The structural information of bioactive peptide is important for the development of peptide-based drugs. Many databases have been developed cataloguing bioactive peptides. However, to our knowledge, database dedicated to collect all the bioactive peptides with known structure is not available yet. Thus, we developed StraPep, a structure database of bioactive peptides. StraPep holds 3791 bioactive peptide structures, which belong to 1312 unique bioactive peptide sequences. About 905 out of 1312 (68%) bioactive peptides in StraPep contain disulfide bonds, which is significantly higher than that (21%) of PDB. Interestingly, 150 out of 616 (24%) bioactive peptides with three or more disulfide bonds form a structural motif known as cystine knot, which confers considerable structural stability on proteins and is an attractive scaffold for drug design. Detailed information of each peptide, including the experimental structure, the location of disulfide bonds, secondary structure, classification, post-translational modification and so on, has been provided. A wide range of user-friendly tools, such as browsing, sequence and structure-based searching and so on, has been incorporated into StraPep. We hope that this database will be helpful for the research community.

关键词： MOLECULAR structure of peptides BIOLOGICAL databases PROTEIN stability

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改进四帧差分运动目标检测算法的FPGA实现

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通信技术 2024年第11期57卷 1213-1220页

作者：严飞孟川郑绪文李楚刘银萍南京信息工程大学自动化学院江苏南京210044 江苏省大气环境与装备技术协同创新中心江苏南京210044 南京信息工程大学应急管理学院江苏南京210044

针对传统的帧间差分运动目标检测算法易出现虚假边缘及边缘缺失等现象,设计了一种改进的四帧差分运动目标检测系统,将图像边缘信息与四帧差分算法相融合对运动目标进行检测,并在现场可编程门阵列(Field Programmable Gate Array,FPGA)... 详细信息

针对传统的帧间差分运动目标检测算法易出现虚假边缘及边缘缺失等现象,设计了一种改进的四帧差分运动目标检测系统,将图像边缘信息与四帧差分算法相融合对运动目标进行检测,并在现场可编程门阵列(Field Programmable Gate Array,FPGA)平台上构建了视频图像处理系统。该系统主要由图像采集模块、图像缓存模块、图像处理模块和图像显示模块4个部分组成。通过OV5640摄像头采集1 024×768分辨率的图像数据,将采集的图像数据存入DDR3中,并采用改进的四帧差分算法对运动目标进行检测与标记,最终传输至高清多媒体接口(High-Definition Multimedia Interface,HDMI)外接显示器实时输出结果。实验结果表明,该系统可以准确检测出摄像头采集的视频源中的多个运动目标,并满足实时检测要求。

关键词：改进四帧差分 FPGA 边缘检测 DDR3 多运动目标检测

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DFT Study of Oxygenated Organic Pollutants Catalyzed by Molybdenum Oxides: Comparison of Reaction Mechanisms of MoO_x + HCHO(x = 1, 2, 3)

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Chinese Journal of Structural Chemistry 2019年第8期38卷 1229-1240页

作者： GAO Xiao-Zhen LIANG yan yanG Jing MENG Xiang-Jun yanG Xiao-Chun JIA Jing-Xian xuwen-Guo Yangquan Municipal Key Laboratory of Quantum Manipulation Shanxi Institute of TechnologyYangquan045000China Department of Chemistry Tangshan Normal CollegeTangshan063000China Institute for Physical Chemistry Beijing Institute of TechnologyBeijing100081China

The reaction mechanisms between formaldehyde and MoOx(x = 1, 2, 3) have been studied thoroughly in this paper. Five reaction pathways were found in three reactions(reactions Ⅰ to Ⅲ) through studying the mechanisms of MoOx(x = 1, 2, 3) catalyzing formaldehyde. Different products were obtained from three reactions. Of all three reactions, the barrier energy of Route ⅡA is the lowest(4.70 kcal/mol), which means in MoOx(x = 1, 2, 3), MoO2 has the best catalytic effect. Compared with other similar non-toxic treatments of formaldehyde, our barrier energy is the lowest. In this research, there was no good leaving group of the compound, so the mechanisms are addition reaction. We speculate that there must be an addition reaction to the more complex reactions to molybdenum oxides and aldehydes. As a chemical reagent for removing formaldehyde, it only absorbs formaldehyde and does not emit other toxic substances outward. Molybdenum oxides retain its original structures of the final products, which means it has excellent stability in the reaction of MoOx(x = 1, 2, 3) + HCHO. The mechanisms of all three reactions are addition reactions, but they are entirely different. As the number of oxygen atoms increases, the reaction mechanisms become simpler.

关键词： reaction mechanism formaldehyde elimination molybdenum oxides addition reaction barrier energy

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Facile synthesis of 3D N-doped porous carbon nanosheets as highly active electrocatalysts toward the reduction of hydrogen peroxide

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NANOSCALE 2018年第31期10卷 14923-14930页

作者： Lu, Nannan Zhang, Tingting yan, Xiaoyi Gu, Yue Liu, He Xu, Zhiqian Xu, Haixin Li, xuwen Zhang, Zhiquan yang, Ming Jilin Univ Coll Chem Changchun 130012 Jilin Peoples R China Jilin Univ Hosp 1 Dept Breast Surg Changchun 130012 Jilin Peoples R China

Constructing three-dimensional (3D) conductive frameworks with high specific surface areas and porous structures is indispensable for their applications as electrocatalysts. In this work, we illustrate for the first time that 3D N-doped porous carbon nanosheets (3D-NS), which are synthesized via a facile one-pot pyrolysis reaction using glucose and melamine as raw materials, can serve as high performance and green electrocatalysts for the reduction of H2O2. Moreover, a series of 3D-NS samples with a controllable content of nitrogen were obtained by adjusting the calcination temperature. From our research, the 3D-NS obtained at 900 degrees C possessed high specific surface areas, porous structures, proper dosages of N atoms, suitable degrees of graphitization and defects. Furthermore, we also illustrate their application in H2O2 electrochemical sensing in physiological environments. Under optimum conditions, the 3D-NS-based sensor displays a wide linear scope in the range of 0.5-14 000 mu M and a low detection limit of 0.18 mu M (S/N = 3). Therefore, with desirable selectivity, stability and anti-interference performance, the proposed sensor can be feasibly applied to detect H2O2 in human serum samples.

关键词： Electrocatalysts

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中医药干预铁死亡治疗炎症性肠病及“炎-癌”转化分子机制研究进展

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中国中西医结合消化杂志 2025年第3期33卷 326-331页

作者：刘新阳史英(审校) 刘金响马小兵闫婷刘旭雯陕西中医药大学陕西咸阳712000 陕西中医药大学第二附属医院消化内科

炎症性肠病(inflammatory bowel disease,IBD)是一种以上皮屏障功能破坏和黏膜慢性炎症为特征的慢性复发性胃肠道疾病,主要包括溃疡性结肠炎和克罗恩病,与肠道免疫反应异常相关,其难治性和癌变风险使得确定新的潜在靶点和发现新的有效... 详细信息

炎症性肠病(inflammatory bowel disease,IBD)是一种以上皮屏障功能破坏和黏膜慢性炎症为特征的慢性复发性胃肠道疾病,主要包括溃疡性结肠炎和克罗恩病,与肠道免疫反应异常相关,其难治性和癌变风险使得确定新的潜在靶点和发现新的有效药物尤为重要。既往研究发现,铁死亡不仅是IBD的潜在治疗靶点,还是非肿瘤性疾病中细胞死亡的重要机制,同时也能抑制结直肠肿瘤的发生与发展。但目前铁死亡在IBD及IBD相关的结直肠肿瘤中的研究尚不足,中药及其相关靶点调控铁死亡的机制还处于探索阶段,以中医药调控铁死亡从而抑制“炎-癌”转化的研究数量较少,故基于铁死亡理论突出中医药临床防治“炎-癌”转化可作为今后的研究方向。

关键词：铁死亡炎症性肠病结直肠癌 “炎-癌”转化中医药治疗

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Fabrication of CoNPs-embedded porous carbon composites based on morphochemical imprinting strategy for detection of H2O2 released from living cells

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ELECTROCHIMICA ACTA 2019年 321卷 134717-000页

作者： Lu, Nannan Zheng, Bo Gu, Yue yan, Xiaoyi Zhang, Tingting Liu, He Xu, Haixin Xu, Zhiqian Li, xuwen Zhang, Zhiquan Jilin Univ Coll Chem Changchun 130012 Jilin Peoples R China Weinan Normal Univ Coll Chem & Mat Weinan City 714099 Peoples R China

Rational construction of biosensor to determine reactive oxygen species (ROS) generated from living cells is one of the great challenges in physiological and pathological fields. Herein, for the first time, a novel Co nanoparticles (CoNPs) embedded walnut-like N-doped porous carbon microsphere (Co@NCS) can be synthesized using dual imprinting strategy by pyrolysis and acid leaching. The distinct morphology and chemical characteristic of melamine cyanurate (MC) aggregates can be imprinted in the carbon source derived from glucose during the pyrolysis process. According to our research, with synergistic effect of CoHPs and NCS, the Co@NCS shows an excellent electrochemical activity toward the reduction of hydrogen peroxide (H2O2). The Co@NCS modified electrode exhibits a wider linear detection response with the range from 0.5 mu M to 7500 mu M and a low detection limit of 88 nM (S/N = 3). Moreover, with desirable selectivity, decent reproducibility and satisfied anti-interference performance, the fabricated biosensor can be applied to determine H2O2 in human serum samples and that released from living cell, indicating the potential applications in the fields of pathological and physiological sensing. (C) 2019 Elsevier Ltd. All rights reserved.

关键词： Co nanoparticles Porous carbon microspheres Biosensor Hydrogen peroxide Living cells

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Analysis of heart rate variation and foetal quiet sleep cycle correlation for normal and suspicious foetuses

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BIOTECHNOLOGY & BIOTECHNOLOGICAL EQUIPMENT 2018年第4期32卷 988-992页

作者： Li, Guangfei Zhang, Song yang, Lin Li, Shufang Wang, yan Zhao, yangyu yang, Yimin Hao, Dongmei Li, xuwen Zhang, Lei Xu, Mingzhou Beijing Univ Technol Coll Life Sci & Bioengn Beijing Peoples R China Peking Univ Hosp 3 Obstet & Gynecol Beijing Peoples R China Beijing Yes Med Devices Co Ltd Beijing Peoples R China Beijing Aerosp Changfeng Co Ltd Beijing Peoples R China

Cardiotocography (CTG) is the basic method of monitoring foetal condition in the perinatal period. However, due to the limited insight into the CTG generation mechanism, some CTG recordings can be mistreated as a predictor of neonatal asphyxia, leading to a wrong assessment of the foetal status and improper obstetric intervention. Therefore, in case of suspicious CTG indications, a reliable verification of the true foetal status is vital for reducing the clinical diagnosis false-positive rate and avoiding the unnecessary obstetrician intervention. The paper presents the results obtained for 44 foetuses on the shares of three heart rate variation (HRV) ranges and quiet sleep cycles. This approach uses the parameters of the HRV range shares and quiet sleep cycles to analyse different types of foetuses. The results obtained show that most parameters reveal significant differences between normal and suspicious groups. This is quite lucrative for defining a set of coefficients, whose incorporation into a classifier will improve the accuracy of distinguishing the normal foetuses from suspicious ones.

关键词： Foetal heart rate foetal quiet sleep HRV range share

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Charge Transfer Platform and Catalytic Amplification of Phenanthroimidazole Derivative: A New Strategy for DNA Bases Recognition

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ANALYTICAL CHEMISTRY 2019年第18期91卷 11938-11945页

作者： Lu, Nannan Liu, He Huang, Rui Gu, Yue yan, Xiaoyi Zhang, Tinging Xu, Zhiqian Xu, Haixin Xing, Yue Song, Yu Li, xuwen Zhang, Zhiquan Jilin Univ Coll Chem Changchun 130012 Jilin Peoples R China

Research about DNA composition has been concentrated on DNA damage in the past few decades. However, it still remains a great challenge to construct a rapid, facile, and accurate approach for simultaneously monitoring four DNA bases, guanine (G), adenine (A), thymine (T), and cytosine (C). Herein, a novel electrochemical sensor based on phenanthroimidazole derivative, 2-(4-bromophenyl)-1-phenyl-1H-phenanthro[9,10-d]-imidazole (PPI), is successfully fabricated by a simple electrochemical method. The bromophenyl group in PI could expand their aromatic plane, induce the pi-conjugated extension, and enhance the charge transfer and pi-pi interaction. The phenyl group at N1 position could regulate the intermolecular interaction, which could promote the possibility of intermolecular connection. The PPI polymer (poly(PPI)) with pi-electron enriched conjugation architecture has been applied in simultaneous determination of G, A, T, and C in neutral solution by square wave voltammetry (SWV) method with well-separated peak potentials at 0.714, 1.004, 1.177, and 1.353 V, respectively. The sensor functionalized with poly(PPI) exhibits wide linear response for G, A, T, and C in the concentration ranges of 3-300, 1-300, 30-800, and 20-750 mu M, respectively. With favorable selectivity, stability, and reproducibility, the sensor is successfully utilized to monitor four DNA bases in real samples, displaying a promising prospect for electrochemical sensing devices.

关键词： Cytosine Genetics Electrodes Oxidation Acid and base chemistry

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南海天然气水合物钻采机理与调控研究进展

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中国科学基金 2021年第6期35卷 940-951页

作者：孙金声程远方秦绪文孙友宏金衍王志远李淑霞陆程屈沅治吕开河王成文王金堂王韧中国石油大学(华东) 青岛266580 中国石油集团工程技术研究院有限公司北京102206 中国地质调查局北京100037 广州海洋地质调查局广州510075 中国地质大学(北京) 北京100083 中国石油大学(北京) 北京102249 中国地质调查局油气资源调查中心北京100083

海域天然气水合物试采存在井壁易失稳、井漏、流动安全风险高、储层改造困难、单井日产气量低、稳产时间短等一系列技术难题,水平井、多分支井等有望提高产气量的复杂结构井钻采难度更大。本文基于对国内外水合物钻采研究进展以及已开... 详细信息

海域天然气水合物试采存在井壁易失稳、井漏、流动安全风险高、储层改造困难、单井日产气量低、稳产时间短等一系列技术难题,水平井、多分支井等有望提高产气量的复杂结构井钻采难度更大。本文基于对国内外水合物钻采研究进展以及已开展天然气水合物勘探、试采工程现状的跟踪调研,总结分析了海域天然气水合物试采面临的关键技术难题,进而根据我国南海天然气水合物试采工程特性,对天然气水合物储层力学特性动态演化规律及工程响应机制、井筒工作液与天然气水合物储层作用机理和调控方法、天然气水合物钻采井筒多相流动障碍形成机制与安全控制方法、储层天然气水合物相变和渗流多场时空演化规律、天然气水合物储层结构改造理论与高效开发模式等方面研究进展进行了论述,以期为我国海域天然气水合物钻采理论及技术的发展提供借鉴。

关键词：南海天然气水合物钻采工程力学特性井筒工作液相变及渗流特征

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番茄SlMAPK6基因克隆及其表达特性分析

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南方农业学报 2020年第7期51卷 1625-1633页

作者：岳宁波李云洲李玉龙潘鹏程潘寅涛王勇须文吴浪闫见敏贵州大学农学院贵阳550025 西北农林科技大学资源与环境学院陕西杨凌712100 中国农业大学园艺学院北京100083

【目的】克隆番茄促分裂原活化蛋白激酶(MAPK)基因SlMAPK6,并分析其在不同非生物胁迫及信号物质处理下的表达模式,为深入探究SlMAPK6基因在番茄逆境响应中调控机制提供理论参考。【方法】采用同源克隆技术从矮番茄中克隆SlMAPK6基因cDN... 详细信息

【目的】克隆番茄促分裂原活化蛋白激酶(MAPK)基因SlMAPK6,并分析其在不同非生物胁迫及信号物质处理下的表达模式,为深入探究SlMAPK6基因在番茄逆境响应中调控机制提供理论参考。【方法】采用同源克隆技术从矮番茄中克隆SlMAPK6基因cDNA全长序列,并进行生物信息学分析,采用实时荧光定量PCR检测矮番茄幼苗在干旱(20%PEG-6000)、盐(300 mmol/L NaCl)及信号物质[0.50 mmol/L水杨酸(SA)和0.10 mmol/L 2,1,3-苯并噻二唑(BTH)]处理下SlMAPK6基因的表达模式。【结果】克隆获得SlMAPK6基因cDNA全长序列为1360 bp,开放阅读框(ORF)为1131 bp,编码376个氨基酸残基,其编码蛋白理论等电点(pI)6.76,不稳定指数44.36,脂肪系数90.00,为不稳定的强脂溶性蛋白,亲水性平均值(GRAVY)-0.396,亲水性氨基酸均匀分布在整个肽链中,故该蛋白为亲水性蛋白;亚细胞定位于细胞核及胞浆质中,无跨膜区,含有36个磷酸化位点,其中丝氨酸(Ser)磷酸位点19个、苏氨酸(Thr)磷酸位点9个。SlMAPK6蛋白二级结构中,α-螺旋占38.03%,延伸链占10.37%,无规则卷曲占51.60%。SlMAPK6蛋白与马铃薯StMAPK4、风铃辣椒CbMAPK4和中华辣椒CcMAPK4蛋白同源性均为99.47%。SlMAPK6和SlMAPK5蛋白的亲缘关系最近,与拟南芥MAPK家族B亚族成员AtMAPK4、AtMPK5、AtMPK11、AtMPK12和AtMPK13蛋白的亲缘关系也较近。经SA、BTH、NaCl和PEG-6000处理后,SlMAPK6基因均出现抑制表达,说明SlMAPK6基因负向调控番茄植株的逆境响应。【结论】SlMAPK6基因可能参与负调控番茄植株的抗病和抗逆胁迫机制。SlMAPK6蛋白通过Ser或Thr磷酸化识别细胞信号的传导功能,在矮番茄逆境胁迫响应中发挥重要作用。

关键词：番茄促分裂原活化蛋白激酶6(MAPK6) 基因克隆信号物质非生物胁迫表达特性

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