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Cα–Cβ Bond Cleavage Occurs at the Side Chain of the N-Terminal Phenylalanine Residue During CID of Tyrosine-Containing Peptide Radical Cations

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Cα–Cβ Bond Cleavage Occurs at the Side Chain of the N-Ter...

《补续全蜀艺文志》所见苏轼著作、年谱及纪传考论

2018年中国质谱学术大会（CMSC2018）

作者： Xiaoyan Mu wai kit Tang Naiping Dong Mengzhu Li Chi-kit Siu Ivan K.Chu Department of Chemistry University of Hong Kong Department of Chemistry City University of Hong Kong

Molecular radical cationic peptides(M) display rich and diverse gas-phase ion chemistry that can differ substantially from that of their protonated counterparts. Dissociation of M radical cations can provide relevant structural information for protein sequencing, often complementary to that obtained using traditional approaches1-2. In this study, low-energy collision-induced dissociation(CID) of a series of tyrosine-containing peptide molecular radical cations having an N-terminal phenylalanine residue led to new products resulting from radical-mediated C–C bond cleavage at the side chain of the phenylalanine residue. The chemical identity of the species formed through side chain loss(91 Da) occurring via N-terminal C–C bond cleavage was examined using a combination of lowenergy CID experiments, isotopic labeling mass spectrometric experiments, and density functional theory calculations. This unusual dissociation process occurs with fascinating unimolecular gas phase ion chemistry and requires a π-radical cationic tyrosine residue with significant spin density delocalized into the N-terminal amino group. The radical character at the resulting –NH moiety then induces β-scission at the side chain C–C bond of the phenylalanine residue. This unique neutral radical loss(91 Da) from the N-terminal phenylalanine residue, observed here for the first time, should provide additional sequence information for biological tandem mass spectrometry. This discovery also demonstrates the role of the NH group in facilitating C–C bond cleavage of the phenylalanine residue by the proximal tyrosine π-radical cation, probably involving a through-space electron transfer process.

关键词： Radical-site migration hydrogen atom transfer proton transfer Cα–Cβ bond cleavage 91 Da loss

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四川图书馆学报 2024年第4期 93-100页

作者：马康雅四川大学文学与新闻学院成都610207

明杜应芳、胡承诏辑纂的《补续全蜀艺文志》是一部重要的四川地方艺文总集。该志载录苏轼著作33篇,《东坡年谱》1份,与苏轼有关的纪传55则。由于该志成于众手,所辑苏轼著作存在题目有别、文献异文、内容增损的问题。该志收录的《东坡年... 详细信息

明杜应芳、胡承诏辑纂的《补续全蜀艺文志》是一部重要的四川地方艺文总集。该志载录苏轼著作33篇,《东坡年谱》1份,与苏轼有关的纪传55则。由于该志成于众手,所辑苏轼著作存在题目有别、文献异文、内容增损的问题。该志收录的《东坡年谱》并未标明来源,按双行小字“燕石斋”索骥,此年谱实承王世贞《苏长公外纪》引王宗稷《东坡先生年谱》而来。《补续全蜀艺文志》中与苏轼相关的其他文献,多为后人评价及纪闻轶事,反映了以杜应芳为代表的蜀中后学对苏轼的接受。

关键词：《补续全蜀艺文志》文献校勘《东坡年谱》

Efficacy of vasopressin, steroid, and epinephrine protocol for in-hospital cardiac arrest resuscitation: a systematic review and meta-analysis of randomized controlled trials with trial sequential analysis

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Journal of Geriatric Cardiology 2022年第9期19卷 705-711页

作者： Danish Iltaf Satti Yan Hiu Athena Lee Keith Sai kit Leung Jeremy man Ho Hui Thompson Ka Ming Kot Arslan Babar Gauranga mahalwar Abraham KC wai Tong Liu Leonardo Roever Gary Tse Jeffrey Shi Kai Chan International Health Informatics Study(IHIS)Network Cardiovascular Analytics Group Hong KongChina-UK Collaboration Emergency Medicine Unit Li Ka Shing Fac-ulty of MedicineThe University of Hong KongHong KongChina Aston Medical School Faculty of Health&Life SciencesAston UniversityBirminghamUnited Kingdom Li Ka Shing Faculty of Medicine The University of Hong KongHong KongChina Department of Anaesthesia and Pain Service Princess Margaret HospitalLai Chi KokKowloonHong KongChina Department of Medicine Cleveland Clinic FoundationClevelandUSA Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease Department of CardiologyTianjin Institute of Cardi-ologySecond Hospital of Tianjin Medical UniversityTianjinChina Department of Clinical Research Federal Uni-versity of UberlândiaUberlândiaBrazil Kent and Medway Medical School CanterburyKentUnited Kingdom 不详

OBJECTIVES To assess the effect of vasopressin,steroid and epinephrine(VSE)combination therapy on return of spontan-eous circulation(ROSC)after in-hospital cardiac arrest(IHCA),and test the conclusiveness of evidence using trial sequential ana-lysis(TSA).METHODS The systematic search included PubMed,EMBASE,Scopus,and Cochrane Central Register of Controlled *** controlled trials(RCTs)that included adult patients with IHCA,with at least one group receiving combined VSE therapy were *** was extracted independently by two *** main outcome of interest was *** out-comes included survival to hospital discharge or survival to 30 and 90 days,with good neurological *** We included a total of three RCTs(n=869).Results showed that VSE combination therapy increased ROSC(risk ra-tio=1.41;95%CI:1.25-1.59)as compared to *** demonstrated that the existing evidence is *** was also validated by the alpha-spending adjusted relative risk(1.32[1.16,1.49],P<0.0001).Other outcomes could not be meta-analysed due to differences in timeframe in the included *** VSE combination therapy administered in cardiopulmonary resuscitation led to improved rates of ***-ture trials of VSE therapy should evaluate survival to hospital discharge,neurological function and long-term survival.

关键词： resuscitation analysis return

Pre-lung transplant measures of reflux on impedance are superior to p H testing alone in predicting early allograft injury

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World Journal of Gastroenterology 2015年第30期21卷 9111-9117页

作者： wai-kit Lo Robert Burakoff Hilary J Goldberg Natan Feldman Walter W Chan Division of Gastroenterology Hepatology and EndoscopyBrigham and Women’s Hospital Department of Gastroenterology VA Boston Healthcare System Harvard Medical School Division of Pulmonary and Critical Care Medicine Brigham and Women’s Hospital

AIM:To evaluate pre-lung transplant acid reflux on p H-testing vs corresponding bolus reflux on multichannel intraluminal impedance(MII) to predict early allograft ***:This was a retrospective cohort study of lung transplant recipients who underwent pretransplant combined MII-p H-testing at a tertiary care center from January 2007 to November 2012. Patients with pre-transplant fundoplication were excluded. Time-to-event analysis was performed using a Cox proportional hazards model to assess associations between measures of reflux on MII-p H testing and early allograft injury. Area under the receiver operating characteristic(ROC) curve(c-statistic) of the Cox model was calculated to assess the predictive value of each reflux parameter for early allograft injury. Six p H-testing parameters and their corresponding MIImeasures were specified a priori. The p H parameters were upright,recumbent,and overall acid reflux exposure; elevated acid reflux exposure; total acid reflux episodes; and acid clearance time. The corresponding MII measures were upright,recumbent,and overall bolus reflux exposure; elevated bolus reflux exposure; total bolus reflux episodes; and bolus clearance ***:Thirty-two subjects(47% men,mean age:55 years old) met the inclusion criteria of the study. Idiopathic pulmonary fibrosis(46.9%) repres e n t e d t h e m o s t c o m m o n p u l m o n a r y d i a g n o s i s leading to transplantation. Baseline demographics,pre-transplant cardiopulmonary function,number of lungs transplanted(unilateral vs bilateral),and posttransplant proton pump inhibitor use were similar between reflux severity groups. The area under the ROC curve,or c-statistic,of each acid reflux parameter on pre-transplant p H-testing was lower than its bolus reflux counterpart on MII in the prediction of early allograft injury. In addition,the development of early allograft injury was significantly associated with three pre-transplant MII measures of bolus reflux:overal

关键词： Gastroesophageal reflux Lung transplant Multichannel intraluminal impedance pH-monitoring Allograft injury

A Weighted Multi-Domain Spectral Penalty Method with Inhomogeneous Grid for Supersonic Injective Cavity Flows

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Communications in Computational Physics 2009年第5期5卷 986-1011页

作者： wai-Sun Don David Gottlieb Jae-Hun Jung Division of Applied mathematics Brown UniversityProvidenceRI 02912USA Department of mathematics University of Massachusetts at DartmouthNorth DartmouthMA 02747-2300USA

In[***.192(1),pp.325-354(2003)],we have developed a multidomain spectral method with stable and conservative penalty interface conditions for the numerical simulation of supersonic reactive recessed cavity flows with homogeneous *** this work,the previously developed methodology is generalized to inhomogeneous grid to simulate the two dimensional supersonic injector-cavity ***-physical modes in the solution generated at the domain interfaces due to the spatial grid inhomogeneity are minimized using the new weighted multi-domain spectral penalty *** proposed method yields accurate and stable solutions of the injector-cavity system which agree well with experiments *** the direct numerical simulation of the injector-cavity system using the weighted method,the geometric effect of the cavity wall on pressure fluctuations is *** is shown that the recessed slanted cavity attenuates pressure fluctuations inside cavity enabling the cavity to act potentially as a stable flameholder for scramjet engine.

关键词： Penalty interface conditions weighted multi-domain spectral penalty methods supersonic recessed cavity flame-holder compressible Navier-Stokes equations

加速计算高分子溶液中流体力学相互作用的机器学习方法

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分子科学学报 2024年第1期40卷 51-56页

作者：杨毅恩马琳丁明明广东工业大学物理与光电工程学院广东广州510006 广东工业大学轻工化工学院广东广州510006

对于研究高分子溶液的动力学行为来说,计算分子动力学(MD)采用的隐式溶剂模型中的流体动力学相互作用(HI)是极其重要的。对于计算HI来说,Cholesky方法是最常用到的分解扩散张量的方法。然而,当体系包含粒子的数目较大时,该方法所需的计... 详细信息

对于研究高分子溶液的动力学行为来说,计算分子动力学(MD)采用的隐式溶剂模型中的流体动力学相互作用(HI)是极其重要的。对于计算HI来说,Cholesky方法是最常用到的分解扩散张量的方法。然而,当体系包含粒子的数目较大时,该方法所需的计算量往往大到难以承受。因此,开发计算HI的高效率技术非常必要。近来,机器学习,特别是深度神经网络(DNN),已经在计算多体相互作用方面得到了显著提升。该技术可以显著减少MD模拟所需的计算时间,因此受到了越来越多的关注。在本项研究中,通过应用机器学习方法,我们发展了一种用于加速计算HI的DNN模型,其相互作用训练集通过针对高分子和溶剂的MD模拟来获取。该DNN模型则通过Deepmd-kit软件包来训练。我们选取表现最好的模型,用以取代对扩散张量的分解。计算得到的高分子链的回转半径和扩散系数用来验证模型的精确度。测试结果表明,相较于显式溶剂模型,我们的DNN模型在计算单链的回转半径和扩散系数方面具有优秀的计算精度。此外,该方法还具有两个显著优势。首先,设计训练集只需要特定链长的一条链,其结果却可以应用于其他链长却不影响计算精度。这就大大降低了训练需求。其次,运行时间与链长线性相关,这就使得计算HI的计算成本也大幅缩减。总之,我们开发的方法提供了一种针对长期悬而未决的计算高分子溶液中的HI的成本过于高昂的解决思路。

关键词：流体力学相互作用机器学习深度神经网络

Does Minimizing Ventricular Pacing Reduce the Incidence of Atrial Fibrillation ? A Systematic Review and Meta-analysis of Randomized Controlled Trials

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Cardiovascular Innovations and Applications 2020年第3期5卷 1-7页

作者： Ishan Lakhani Mengqi Gong Cheuk wai Wong George Bazoukis Konstantinos PLetsas Guangping Li Khalid bin Wahleed Yunlong Xia Adrian Baranchuk Gary Tse Keith Sai kit Leung Tong Liu Dong Chang Laboratory of Cardiovascular Physiology Li Ka Shing Institute of Health SciencesHong Kong Special Administrative RegionPeople’s Republic of China Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease Department of CardiologyTianjin Institute of CardiologySecond Hospital of Tianjin Medical UniversityTianjin 300211People’s Republic of China Li Ka Shing Faculty of Medicine The University of Hong KongHong KongSpecial Administrative RegionPeople’s Republic of China Second Department of Cardiology Laboratory of Cardiac ElectrophysiologyEvangelismos General Hospital of AthensAthensGreece Department of Cardiology First Affi liated Hospital of Dalian Medical UniversityDalianChina Division of Cardiology Kingston General HospitalQueen’s UniversityKingstonOntarioCanada Xiamen Cardiovascular Hospital Xiamen UniversityXiamenFujianPeople’s Republic of China Aston Medical School Aston UniversityBirminghamUnited Kingdom

Background:Right ventricular pacing disrupts atrioventricular synchrony and increases the risk of atrial fi brillation(AF).However,whether algorithms for minimizing ventricular pacing reduce the incidence of AF remains ***,we conducted a systematic review and meta-analysis to compare the incidence of AF between minimizing ventricular pacing and conventional pacing protocols in patients with pacemakers ***:The PubMed,Embase,and Cochrane Library databases were searched up to August 1,2017,for randomized controlled trials that reported the incidence of AF in patients with and without the use of algorithms for minimizing ventricular ***:Eleven studies comprising 5705 participants(61%males,mean age 71 years[standard deviation 11 years])were fi nally included in the *** mean follow-up duration was 24 *** of algorithms for minimizing ventricular pacing signifi cantly reduced the incidence of AF,with an odds ratio of 0.74(95%confi dence interval 0.55–1.00;P<0.05).There was moderate heterogeneity among studies(I 2=63%).Conclusions:The incidence of AF was reduced by 26%with use of algorithms for minimizing ventricular *** incorporation of such algorithms in routine clinical practice should in theory lead to a decrease in AF-related morbidity and mortality.

关键词： Atrial fibrillation minimizing ventricular pacing pacemaker

基于CKB/p53信号通路探讨白花丹醌对人肝癌细胞增殖和凋亡的影响

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中国中药杂志 2024年第9期49卷 2345-2354页

作者：周凤玲袁彬叶一娴邓舒烨马静刘红马远征韦燕飞广西中医药大学基础医学院广西南宁530200 广西高校中药神经-代谢及免疫药理重点实验室广西南宁530200 广西中医药大学第一附属医院广西南宁530024

基于CKB/p53信号通路研究白花丹醌对人肝癌Huh-7细胞增殖和凋亡的影响及其作用机制。将白花丹醌1~12μmol·L^(-1)处理Huh-7细胞,进行细胞增殖和活性cell counting kit-8(CCK-8)实验,确定1、3、6μmol·L^(-1)为低、中、高浓度用于后续... 详细信息

基于CKB/p53信号通路研究白花丹醌对人肝癌Huh-7细胞增殖和凋亡的影响及其作用机制。将白花丹醌1~12μmol·L^(-1)处理Huh-7细胞,进行细胞增殖和活性cell counting kit-8(CCK-8)实验,确定1、3、6μmol·L^(-1)为低、中、高浓度用于后续实验。采用规律成簇的间隔短回文重复序列(clustered regularly interspaced short palindromic repeats,CRISPR)/CRISPR相关蛋白(CRISPR-associated proteins,Cas)-9基因编辑技术敲除Huh-7细胞中的脑型肌酸激酶(creatine kinase,brain type,CKB)基因;CKB过表达慢病毒转染Huh-7细胞上调CKB的表达。通过平板克隆实验检测细胞增殖;流式细胞术检测细胞凋亡;实时荧光定量PCR(quantitative real-time PCR,qRT-PCR)检测CKB的mRNA表达情况;蛋白免疫印迹(Western blot,WB)实验检测CKB、p53、双微体同源基因2(mouse double minute 2 homolog,MDM2)、B淋巴瘤细胞瘤2(B-cell lymphoma 2,Bcl-2)、Bcl-2相关X蛋白(Bcl-2 associated X protein,Bax)和半胱天冬酶(caspase)-3蛋白表达水平。结果显示白花丹醌显著抑制Huh-7细胞增殖,诱导细胞凋亡。与对照组比较,白花丹醌组凋亡水平显著升高,而白花丹醌联合凋亡抑制剂组凋亡水平显著降低。白花丹醌可显著下调CKB、Bcl-2和MDM2蛋白表达水平,上调p53、Bax和caspase-3蛋白表达水平。敲除CKB基因后,Huh-7细胞增殖能力降低,凋亡率升高,Bcl-2和MDM2蛋白表达水平降低,p53、Bax和caspase-3蛋白表达水平升高。上调CKB表达后,Huh-7细胞增殖能力增强,Bcl-2和MDM2蛋白表达水平升高,p53、Bax和caspase-3蛋白表达水平降低。而白花丹醌可逆转过表达CKB对Huh-7细胞增殖和凋亡的作用。该实验表明,白花丹醌可显著抑制Huh-7细胞的增殖能力,其机制可能是通过抑制CKB表达,激活p53信号通路,调控线粒体相关凋亡蛋白的表达,最终诱导细胞凋亡。

关键词：肝癌白花丹醌 CKB p53信号通路增殖凋亡

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荔枝的采后处理及贮藏

世界热带农业信息 1989年第2期 34-36页

作者： wai-kit Nip 唐树良

本文综述报道了侧重于保持荔枝色泽的采后处理和贮藏的各种方法。

关键词：荔枝肉贮藏温度采后处理贮存期限多酚氧化酶荔枝干果皮色泽无色花青素荔枝果皮褐变反应