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Chinese Science Bulletin 1998年第8期43卷 652-656页

作者： LIU Huayin sha yinlin LU Rongjian YANG Huazheng LAI Luhua Institute of Elemento_Organic Chemistry and State Key Laboratory of Elemento_Organic Chemistry Nankai UniversityTianjin 300071China Institute of Physical Chemist ry Peking UniversityBeijing 100871China

Molecular modeling of cyanoacrylates and ureas with D1 protein of Pisum sativum have been presented. Studies show that these two kinds of inhibitors occupy the similar region in the D1 protein. Cyanoacrylates have mor... 详细信息

关键词： photosystemⅡ phenyl ureas cyanoacrylates molecular modeling.

Interaction of HIV-1 fusion peptide and its mutant with lipid membrane

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Chinese Science Bulletin 2000年第9期45卷 819-825页

作者： QIU Yang sha yinlin HUANG Lixin LIN Kechun NIE Songqing Department of Biophysics Beijing Medical UniversityBeijing 100083China Institute of Physical Chemistry Peking UniversityBeijing 100871China

HIVWT and HIVV2E represent the 23 amino acids fusion peptide of HIV-1 gp41 N terminus and its position 2 mutant (Val→Glu). We have studied the structure-function relationship of HIVWT and HIVV2E when they interact with acidic and neutral lipid membranes. The results show that HIVWT and HIVV2E have the same conformational characteristics and tendencies of conformational transition but definitely different functions: HIVWT destabilizes membrane and induces fusion by adopting predominant α-helix conformation when interacting with acidic POPG membrane, its phenylalanine residues can penetrate into the hydrophobic core of POPG bilayer; HIVV2E also adopts predominant α-helix when interacting with POPG membrane, but it cannot destabilize POPG membrane and induce fusion, the phenylalanine residues of it are located near the surface of POPG bilayer. HIVWT and HIVV2E both adopt predominant β-sheet conformation to interact with neutral POPC membrane, and cannot destabilize POPC membrane and induce fusion,

关键词： human immunodeficiency virus type 1 fusion peptide lipid membrane.

Separation and analysis of the soluble trimer of Aβ_(1-40) and its effects on the rise in intracellular calcium

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Chinese Science Bulletin 2006年第7期51卷 830-838页

作者： ZHENG Xiaohui WANG Lijun ZHANG Lan HONG Yuankai HUANG Lixin sha yinlin Single-molecule and Nanobiology Laboratory. Department of Biophysics School of Basic Medical Sciences Peking University Beijing 100083 China

The oligomers of Aβ1-40 peptide in PBS buffer solution were analyzed by SEC and native PAGE, and the trimer of Aβ1-40 was also isolated by SEC. In addition, the effects of the soluble Aβ1-40 trimer on intracellular free calcium (Ca2+) balance of hippocampal neurons of postnatal rats were investi- gated by fluorescence microscopy. The experimental results indicated that Aβ1-40 peptide existed in the form of low molecular weight oligomers in 0.231 mmol/L fresh Aβ1-40 solution (20 mmol/L sodium phosphate buffer, pH 7.4, 0.02% sodium azide) within 24 h and the soluble trimer was the most abundant species. Both the trimeric and the fibrillar Aβ1-40 were able to increase the intracellular Ca2+ concentration, but the Aβ1-40 trimer caused a gradual rise and the potential was also stronger than that of the fibrils at the same concentration. In addition there were dif- ferent response modes for trimeric and fibrillar Aβ1-40, meaning that there are different mechanisms of in- crease in intracellular Ca2+ caused by Aβ1-40.

关键词：钙三聚物分离 SEC 色谱分析

Gold nanoflowers for 3D volumetric molecular imaging of tumors by photoacoustic tomography

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Nano Research 2015年第7期8卷 2152-2161页

作者： Yuanyuan Jiang Zijian Deng Dan Yang Xin Deng Qi Li yinlin sha Changhui Li Dongsheng Xu Beijing National Laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry of Unstable and Stable Species College of Chemistry and Molecular Engineering Peking University Beijing 100871 China Department of Biomedical Engineering College of Engineering Peking University Beijing 100871 China Single-molecule and Nanobiology Laboratory Department of Biophysics School of Basic Medical Sciences and Biomed-X Center Peking University Beijing 100191 China These authors contributed equally to this work.

By binding molecular probes that target tumor cells, gold nanoparticles （AuNPs） with superior characteristics have shown great potential in tumor molecular imaging studies. The non-invasive, high-resolution, and three-dimensional imaging of the targeted AuNPs within the tumor is desirable for both diagnosis and therapy. In this study, gold nanoflowers （AuNFs） are presented as a novel contrast agent for photoacoustic tomography （PAT）. By binding to folic acid, the molecular probe, the tail-vein injected AuNFs concentrated within the tumor site in mice; this was clearly visualized by three-dimensional （3D） PAT imaging. In addition, toxicity assay proved that AuNFs were harmless to living cells and animals. Our results demonstrate that AuNFs have great potential in tumor molecular imaging.

关键词： nanoparticles,gold nanoflowers,contrast agents,photoacoustic tomography tumor imaging,molecular imaging

Effect of Ab_(1-40) on membrane permeability and intracellular free Ca^(2+) of nerve cells

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Chinese Science Bulletin 2003年第10期48卷 974-978页

作者： MA Xiaocui, sha yinlin, LIN Kechun & NIE Songqing Department of Biophysics, Peking University Health Science Center, Beijing 100083, China

The effects of soluble and fibrillar Ab1-40 on membrane permeability and intracellular free Ca2+ of nerve cells were investigated by the laser confocal microscopy. Results indicate that: i) Effects of soluble and fibrillar Ab1-40 on cell membrane permeability are both concentration-de- pendent. Soluble Ab1-40 increases membrane permeability only at concentration of 3 mmol/L, while the toxic effect of fibrillar Ab1-40 is much stronger, its evident effect begins from 1 mmol/L. When its concentration rose to 3 mmol/L, not only the membrane permeability increased, but also the nuclear membrane broke seriously. ii) Both soluble and fibrillar Ab1-40 at high concentrations increased the intracellular free Ca2+, and the increased amplitudes are concentration-dependent. However, the fibrillar one induces the increase of intracellular Ca2+ much quicker and synchronously. These results indicate that some correlation exists between the neurotoxicity of high concentration soluble and fibrillar Ab1-40 and the change of physico-chemical properties and intracellular Ca ion imbalance.

关键词： Aβl-40 膜渗透性 Ca^2+ 神经单元细胞神经退化病

Stability Prediction in Smart Grid Using PSO Optimized XGBoost Algorithm with Dynamic Inertia Weight Updation

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 909-931页

作者： Adel Binbusayyis Mohemmed sha Department of Software Engineering College of Computer Engineering and Sciences in Al-Kharj Prince Sattam Bin Abdulaziz UniversityAl-Kharj11942Saudi Arabia

Prediction of stability in SG(Smart Grid)is essential in maintaining consistency and reliability of power supply in grid *** the fluctuations in power generation and consumption patterns of smart cities assists in effectively managing continuous power supply in the *** also possesses a better impact on averting overloading and permitting effective energy *** though many traditional techniques have predicted the consumption rate for preserving stability,enhancement is required in prediction measures with minimized *** overcome the complications in existing studies,this paper intends to predict stability from the smart grid stability prediction dataset using machine learning *** accomplish this,pre-processing is performed initially to handle missing values since it develops biased models when missing values are mishandled and performs feature scaling to normalize independent data ***,the pre-processed data are taken for training and *** that,the regression process is performed using Modified PSO(Particle Swarm Optimization)optimized XGBoost Technique with dynamic inertia weight update,which analyses variables like gamma(G),reaction time(tau1–tau4),and power balance(p1–p4)for providing effective future stability in *** PSO attains optimal solution by adjusting position through dynamic inertial weights,it is integrated with XGBoost due to its scalability and faster computational speed *** hyperparameters of XGBoost are fine-tuned in the training process for achieving promising outcomes on *** results are measured through evaluation metrics such as MSE(Mean Square Error)of 0.011312781,MAE(Mean Absolute Error)of 0.008596322,and RMSE(Root Mean Square Error)of 0.010636156 and MAPE(Mean Absolute Percentage Error)value of 0.0052 which determine the efficacy of the system.

关键词： Smart Grid machine learning particle swarm optimization XGBoost dynamic inertia weight update

Erratum to： Gold nanoflowers for 3D volumetric molecular imaging of tumors by photoacoustic tomography

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Nano Research 2017年第3期10卷 1104-1104页

作者： Yuanyuan Jiang Zijian Deng Dan Yang Xin Deng Oi Li yinlin sha Changhui Li Dongsheng Xu Beijing National Laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry of Unstable and Stable Species College of Chemistry and Molecular Engineering Peking University Beijing 100871 China Department of Biomedical Engineering College of Engineering Peking University Beijing 100871 China Single-molecule and Nanobiology Laboratory Department of Biophysics School of Basic Medical Sciences and Biomed-X Center Pekincl University Beijing 100191 China

The original version of this article unfortunately missed acknowledgements part. The acknowledgements are as below.

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Humanin Block Neuron Toxicity by Altering Ab Fibrogenesis

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Humanin Block Neuron Toxicity by Altering Ab Fibrogenesis

固定剂、封片剂、温度及除菌方式对量子点标记细胞的影响

8th Chinese International Peptide Symposium

作者： Lan ZHANG, Lixin HUANG, Ping ZOU, Yuankai HONG,Lijun WANG, yinlin sha Single-molecule and Nanobiology Laboratory, Department of Biophysics, School of Basic Medical Sciences, Peking University, Beijing 100083, China

Alzheimer’s disease(AD) is a progressive and ultimately fatal neurological disorder for which there is no effective treatment at present. This disease is characterized pathologically by extracellular senile plaques that contain the Aβand intracellular neurofibrillary tangles. Compelling evidence supports Aβas the "primer mover" and the Aβtoxicity hypothesis is popular and reasonable. Nishimoto group identified a gene, Humanin(HN) cDNA, which encodes a 24-aa peptide that can specifically inhibit cell death induced by familial AD mutant genes, Aβand a wider spectrum of common cell death factors. But it is still uncertain how HNs antagonize Aβneruotoxicity and protect neurons. Since Aβfibrogenesis is very important for its neurotoxicity, we investigate Aβmorphological alteration triggered by HNs to reveal the neuroprotection mechanism of HN peptides, including the relationship between Aβand HNs. Our

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解剖学杂志 2009年第1期32卷 38-40,F0003页

作者：唐岩唐军民李枫战军陈丽赵承军沙印林北京大学基础医学院组织学与胚胎学教研室北京100083 宁夏医学院组织学与胚胎学教研室银川750004 北京大学基础医学院生物物理学系单分子与纳米生物学实验室北京100083

目的:观察不同固定剂、封片剂、温度及除菌方式对3种量子点标记小鼠腹腔巨噬细胞和正常皮肤的影响。方法:利用发射波长为610、523和576nm的3种量子点,以具有吞噬能力的小鼠腹腔巨噬细胞及正常皮肤为载体,观察不同的固定剂、封片剂、温... 详细信息

目的:观察不同固定剂、封片剂、温度及除菌方式对3种量子点标记小鼠腹腔巨噬细胞和正常皮肤的影响。方法:利用发射波长为610、523和576nm的3种量子点,以具有吞噬能力的小鼠腹腔巨噬细胞及正常皮肤为载体,观察不同的固定剂、封片剂、温度及除菌方式对量子点标记细胞及组织的影响。结果:3种量子点对小鼠腹腔巨噬细胞和皮肤组织没有明显的毒性,并且在6～72h内保持荧光不衰减。高于56℃的温度会使量子点失去发射荧光的特性。较好的除菌方式为^(60)Co照射和微孔滤膜过滤。最稳定的封片剂为水溶性的ClearmountTM。吞噬了量子点523的巨噬细胞,可使用多种固定液固定。结论:不同波长量子点标记小鼠腹腔巨噬细胞和皮肤组织的效能受固定剂、封片剂、温度和除灭菌方式的影响。

关键词：量子点巨噬细胞皮肤固定剂封片剂温度除灭菌方式

人树突状细胞摄取量子点后的表面标志与超微结构

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解剖学杂志 2010年第5期33卷 583-586页

作者：唐岩战军常昕莹陈丽董静霞毕振伍沙印林唐军民北京大学基础医学院组织学与胚胎学教研室北京100191 北京大学基础医学院生物物理学系单分子与纳米生物学实验室北京100191

目的：观察人树突状细胞体外摄取量子点后,其形态、表面标志、超微结构的变化.方法：两种量子点与人未成熟树突状细胞体外共孵育,荧光显微镜下观察量子点在树突状细胞内的分布;免疫细胞化学方法检测树突状细胞表面标志;扫描电镜及透射... 详细信息

目的：观察人树突状细胞体外摄取量子点后,其形态、表面标志、超微结构的变化.方法：两种量子点与人未成熟树突状细胞体外共孵育,荧光显微镜下观察量子点在树突状细胞内的分布;免疫细胞化学方法检测树突状细胞表面标志;扫描电镜及透射电镜观察树突状细胞超微结构的改变.结果：与量子点共培养的树突状细胞的细胞质内充满了较强荧光颗粒,共培养前后的树突状细胞表面标志均呈阳性反应.扫描电镜下可见树突状细胞表面有丰富的典型树枝样的突起.透射电镜下可见树突状细胞以胞饮的方式摄入量子点,形成有膜包被的囊泡分布在细胞质内.结论：树突状细胞是通过胞饮作用摄取量子点,且量子点对树突状细胞的形态、表面标志及超微结构没有影响,生物相容性好.

关键词：量子点人树突状细胞荧光超微结构