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基于合并症的住院慢性阻塞性肺疾病患者死亡风险预测模型及验证

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中国医学前沿杂志（电子版） 2024年第6期16卷 24-30页

作者：胡淑婷陈海杰张静内蒙古自治区人民医院呼吸与危重症医学科内蒙古自治区呼和浩特010010 北京大学第三医院呼吸与危重症医学科北京100191

目的采用列线图构建住院慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)患者的死亡风险预测模型并加以验证。方法回顾性分析2017年1月1日至2022年8月1日期间于北京大学第三医院呼吸与危重症医学科住院的1110例COPD患者... 详细信息

目的采用列线图构建住院慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)患者的死亡风险预测模型并加以验证。方法回顾性分析2017年1月1日至2022年8月1日期间于北京大学第三医院呼吸与危重症医学科住院的1110例COPD患者的临床结局。采用随机抽样方法将纳入患者按照7︰3的比例分为训练集(777例)及验证集(333例)。在训练集中通过单、多因素Logistic回归分析COPD患者住院期间死亡的危险因素并建立列线图预测模型。通过受试者操作特征曲线(receiver operating characteristic curve,ROC曲线)及曲线下面积(area under the curve,AUC)评估所建立模型。结果急诊入院、心率大于100次/min、呼吸系统感染、心律失常、低蛋白血症、慢性肾脏病与COPD患者住院期间死亡相关,据此建立的列线图在训练集及验证集中AUC分别为0.899和0.871,判别能力较好。结论本研究建立的列线图预测模型可以较好地预测COPD患者住院期间死亡的风险。

关键词：慢性阻塞性肺疾病合并症预测模型

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壳聚糖改性脂质体的制备与稳定性研究

肇庆学院学报 2024年第2期45卷 29-37页

作者：石文陈海洁肇庆学院食品与制药工程学院广东肇庆526061

实验通过乙醇注入法制备壳聚糖包覆脂质体.以粒径作为指标,通过单因素正交实验优化,确定关键工艺为:大豆卵磷脂浓度为10 mg/mL,壳聚糖浓度为150 mg/mL,剪切速度为7000 r/min、剪切时间为2 min,超声时间为10 min,该工艺制备的脂质体粒径... 详细信息

实验通过乙醇注入法制备壳聚糖包覆脂质体.以粒径作为指标,通过单因素正交实验优化,确定关键工艺为:大豆卵磷脂浓度为10 mg/mL,壳聚糖浓度为150 mg/mL,剪切速度为7000 r/min、剪切时间为2 min,超声时间为10 min,该工艺制备的脂质体粒径为711.38 nm.再考察酪蛋白酸钠、辛烯基酸琥珀酸酐、吐温20和吐温804种稳定剂(1%大豆卵磷脂质量比)对脂质体的影响表明,吐温80效果最佳.研究获得一种稳定性强,粒径较小的包覆脂质体.

关键词：壳聚糖脂质体改性稳定性粒径

Insight into macroscale superlubricity of polyol aqueous solution induced by protic ionic liquid

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Friction 2022年第12期10卷 2000-2017页

作者： Zhiwen ZHENG Xiaolong LIU Hongxiang YU haijie chen Dapeng FENG Dan QIAO State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Currently,macroscale liquid superlubricity remains limited to low applied loads and typical ceramic friction *** this study,a robust macroscale superlubricity with a coefficient of friction(COF)of approximately 0.006 is realized at the bearing steel interface induced by protic ionic liquids(ILs)in propylene glycol aqueous solution,and the lubrication system exhibits excellent anti-corrosion *** show that superlubricity can be achieved by employing ILs with longer alkyl chains over a wide load(700 r/min)*** systematically investigating factors affecting superlubricity,including the IL structure,ionization degree,test conditions,polyol,water-to-alcohol ratio,and lubrication state,the superlubricity mechanism is ***,a thicker and denser stern layer can be formed using ILs with longer alkyl chains,which participates in the tribochemical reaction with the metal substrate to form a tribofilm during *** hydrogen bond network layer formed by the hydrogen ion and polycol aqueous solution can withstand high applied *** can be used to reduce the shear stress of polyols,and enable superlubricity to be achieved under high-speed ***,an inevitable running-in period serves as a dispersing contact stress and dynamically forms a lubricating film,where the lubrication state locates mixed lubrication and then transforms into boundary lubrication as the roughness of the contact surface *** study is expected to significantly promote the development and application of superlubricity in the engineering field.

关键词： macroscale superlubricity ionic liquids(ILs) steel interface corrosion tribochemical reaction

Effect of functional groups on tribological properties of lubricants and mechanism investigation

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Friction 2023年第6期11卷 911-926页

作者： Hongxiang YU haijie chen Zhiwen ZHENG Dan QIAO Dapeng FENG Zhenbin GONG Guojun DONG State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China

Nine organic compounds were utilized as model lubricants to investigate the impact of functional groups on tribological *** Acid with carboxyl showed the best lubrication properties,and fluid film and tribofilm were coexistent in its friction test,bringing a low friction coefficient and wear *** addition,the lubricant with low friction coefficient corresponded to high adsorption energy in density functional theory(DFT)*** the lubricant forming adsorption film with large surface energy displayed small wear rate in friction ***,adsorption energies positively correlated surface *** on the experimental results,the action mechanism of functional groups on tribological properties of lubricants was *** functional groups make lubricant molecules show different adsorption energies and surface *** molecules with high adsorption energy are more likely to adsorb on substrates and form a vertical monolayer,which can maintain a regular molecular brush structure during friction and bring a low friction *** lubricant molecules with high surface energy may be more prone having tribochemical reactions during friction and forming protective tribofilm,which leads to a low wear rate.

关键词： functional group tribological property adsorption energy surface energy action mechanism

Macroscale superlubricity achieved via hydroxylated hexagonal boron nitride nanosheets with ionic liquid at steel/steel interface

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Friction 2022年第9期10卷 1365-1381页

作者： Zhiwen ZHENG Xiaolong LIU Guowei HUANG haijie chen Hongxiang YU Dapeng FENG Dan QIAO State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou 730050China

Macroscale superlubricity is a prospective strategy in modern tribology to dramatically reduce friction and wear of mechanical equipment;however,it is mainly studied for point-to-surface contact or special friction pairs in *** this study,a robust macroscale superlubricity for point-to-point contact on a steel interface was achieved for the first time by using hydroxylated modified boron nitride nanosheets with proton-type ionic liquids(ILs)as additives in ethylene glycol aqueous(EG_(aq)).The detailed superlubricity process and mechanism were revealed by theoretical calculations and segmented *** results indicate that hydration originating from hydrated ions can significantly reduce the shear stress of EG_(aq),which plays an essential role in achieving ***,the IL induces a tribochemical reaction to form a friction-protective *** boron nitride nanosheets(HO-BNNs)function as a polishing and self-repairing agent to disperse the contact stress between friction *** involves the change in lubrication state from boundary lubrication to mixed *** finding can remarkably extend the application of superlubricity for point-to-point contact on steel surfaces for engineering applications.

关键词： macroscale superlubricity ionic liquid(IL) hydroxylated boron nitride steel/steel interface mixed lubrication

基于多元统计分析评价不同干燥方法对金钱草中多元指标成分的影响

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中国药学杂志 2024年第5期59卷 398-408页

作者：周永逸陈海杰薛佳邹立思吴楠袁嘉欢刘训红蔡芷辰陈翠花杨薇程建明南京中医药大学药学院南京210023 江苏省经典名方工程研究中心南京210023

目的探究不同干燥方法对金钱草中多元指标成分的影响。方法采用超高效液相色谱-三重四极杆/线性离子阱质谱(UHPLC-QTRAP-MS/MS)同时测定不同干燥方法下金钱草中黄酮、有机酸、氨基酸及核苷类共44种指标成分的含量;根据44种目标成分的含... 详细信息

目的探究不同干燥方法对金钱草中多元指标成分的影响。方法采用超高效液相色谱-三重四极杆/线性离子阱质谱(UHPLC-QTRAP-MS/MS)同时测定不同干燥方法下金钱草中黄酮、有机酸、氨基酸及核苷类共44种指标成分的含量;根据44种目标成分的含量,用聚类分析(HCA)、灰色关联度分析(GRA)及逼近理想解排序方法(TOPSIS)法对不同干燥方法下金钱草样品进行综合评价。结果HCA结果显示,7个不同干燥方法主要分为2类,第1类为晒干和阴干,第2类为不同温度烘干、微波干燥和冷冻干燥;综合GRA和TOPSIS结果,晒干的金钱草样品综合质量较好,阴干和冷冻干燥也可以作为代替干燥方法。结论该研究可为揭示金钱草传统干燥方法科学内涵提供依据,同时为金钱草药材产地加工时干燥方法的优选提供基础资料。

关键词：金钱草干燥方法超高效液相色谱-三重四极杆/线性离子阱质谱多元指标成分多元统计分析

Nonlinear proinflammatory effect of short-term PM_(2.5)exposure:A potential role of lipopolysaccharide

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Journal of Environmental Sciences 2024年第2期136卷 292-300页

作者： Fangxia Shen Mutong Niu Haoxuan chen Ting Zhang Jing Li haijie Tong Yan Wu School of Space and Environment Beihang UniversityBeijing 100191China College of Environmental Sciences and Engineering Peking UniversityBeijing 100871China Institute of Surface Science Helmholtz-Zentrum HereonGeesthacht 21502Germany School of Environmental Science and Engineering Shandong UniversityJinan 250100China

The association between PM_(2.5)(particulate matter≤2.5μm)short-term exposure and its health effect is non-linear from the epidemiological *** this nonlinearity is suggested to be related with the PM_(2.5)heterogeneity,however,the underlying biological mechanism is still ***,a total of 38 PM_(2.5)filters were collected continuously for three weeks in winter Beijing,with the ambient PM_(2.5)varying between 10 and 270μg/m^(3).Human monocytes-derived macrophages(THP-1)were treated with PM_(2.5)water-soluble elutes at10μg/mL to investigate the PM_(2.5)short-term exposure effect from a proinflammatory *** proinflammatory cytokine tumor necrosis factor(TNF)induced by the PM_(2.5)elutes at equal concentrations were unequal,showing the heterogeneity of PM_(2.5)proinflammatory *** the various chemical and biological components,lipopolysaccharide(LPS)showed a strong positive association with the TNF ***,some outliers were observed among the TNF-LPS ***,for PM_(2.5)from relatively clean air episodes,the higher LPS amount corresponded to relatively low TNF *** this phenomenon was also observed in the promotion tests by treating macrophages with PM_(2.5)elutes dosed with additional trace *** expression analysis indicated the involvement of oxidative-stress related genes in the LPS signaling ***,a potential oxidative-stress-mediated suppression on the PM_(2.5)-borne LPS proinflammatory effect was proposed to be accounted for the ***,the results showed the differential role of LPS in the heterogeneity of PM_(2.5)proinflammatory effects from a component-based *** experimental studies are needed to elucidate the signaling pathway of LPS attached on PM_(2.5)from different air quality episodes.

关键词： Fine PM PM_(2.5)pro-inflammatory effects Aerosol health effect Endotoxin Oxidative stress

Dynamic gut microbiome-metabolome in cationic bovine serum albumin induced experimental immune-complex glomerulonephritis and effect of losartan and mycophenolate mofetil on microbiota modulation

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Journal of Pharmaceutical Analysis 2024年第4期14卷 562-577页

作者： Wenying Shi Zhaojun Li Weida Wang Xikun Liu haijie Wu Xiaoguang chen Xunrong Zhou Sen Zhang State Key Laboratory of Bioactive Substances and Functions of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing100050China State Key Laboratory of Functions and Applications of Medicinal Plants College of PharmacyGuizhou Provincial Engineering Technology Research Center for Chemical Drug R&DGuizhou Medical UniversityGuiyang550004China Department of Medicine Solna Center for Molecular MedicineKarolinska University Hospital and Karolinska InstituteStockholm17176Sweden Department of Pharmacy The Second Affiliated Hospital of Guizhou University of Traditional Chinese MedicineGuiyang550001China

Dynamic changes in gut dysbiosis and metabolomic dysregulation are associated with immune-complex glomerulonephritis(ICGN).However,an in-depth study on this topic is currently ***,we report an ICGN model to address this *** was induced via the intravenous injection of cationized bovine serum albumin(c-BSA)into Sprague-Dawley(SD)rats for two weeks,after which mycophenolate mofetil(MMF)and losartan were administered *** and six weeks after ICGN establishment,fecal samples were collected and 16S ribosomal DNA(rDNA)sequencing and untargeted metabolomic were *** microbiota transplantation(FMT)was conducted to determine whether gut normali-zation caused by MMF and losartan contributed to their renal protective effects.A gradual decline in microbial diversity and richness was accompanied by a loss of renal *** 18 genera were found to have significantly different relative abundances between the early and later stages,and Marvinbryantia and Allobaculum were markedly upregulated in both *** metabolomics indicated that the tryptophan metabolism was enhanced in ICGN,characterized by the overproduction of indole and kynurenic acid,while the serotonin pathway was *** of losartan and MMF ameliorated microbial dysbiosis and reduced the accumulation of indoxyl conjugates in *** using feces from animals administered MMF and losartan improved gut dysbiosis by decreasing the Firmicutes/Bacteroidetes(F/B)ratio but did not improve renal *** findings indicate that ICGN induces serous gut dysbiosis,wherein an altered tryptophan metabolism may contribute to its *** and losartan significantly reversed the gut microbial and metabolomic dysbiosis,which partially contributed to their renoprotective effects.

关键词： Immune-complex glomerulonephritis Gut microbiome Metabolomics Fecal microbiota transplant Tryptophan metabolism

Correcting Climate Model Sea Surface Temperature Simulations with Generative Adversarial Networks:Climatology,Interannual Variability,and Extremes

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Advances in Atmospheric Sciences 2024年第7期41卷 1299-1312页

作者： Ya WANG Gang HUANG Baoxiang PAN Pengfei LIN Niklas BOERS Weichen TAO Yutong chen BO LIU haijie LI State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Laboratory for Regional Oceanography and Numerical Modeling Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Earth System Modelling School of Engineering and DesignTechnical University of MunichOttobrunn 85521Germany Potsdam Institute for Climate Impact Research Potsdam 14412Germany Department of Mathematics and Global Systems Institute University of ExeterExeter EX44QEUK CMA Earth System Modeling and Prediction Centre(CEMC) Chinese Academy of Meteorological SciencesBeijing 100081China

Climate models are vital for understanding and projecting global climate change and its associated ***,these models suffer from biases that limit their accuracy in historical simulations and the trustworthiness of future *** these challenges requires addressing internal variability,hindering the direct alignment between model simulations and observations,and thwarting conventional supervised learning ***,we employ an unsupervised Cycle-consistent Generative Adversarial Network(CycleGAN),to correct daily Sea Surface Temperature(SST)simulations from the Community Earth System Model 2(CESM2).Our results reveal that the CycleGAN not only corrects climatological biases but also improves the simulation of major dynamic modes including the El Niño-Southern Oscillation(ENSO)and the Indian Ocean Dipole mode,as well as SST ***,it substantially corrects climatological SST biases,decreasing the globally averaged Root-Mean-Square Error(RMSE)by 58%.Intriguingly,the CycleGAN effectively addresses the well-known excessive westward bias in ENSO SST anomalies,a common issue in climate models that traditional methods,like quantile mapping,struggle to ***,it substantially improves the simulation of SST extremes,raising the pattern correlation coefficient(PCC)from 0.56 to 0.88 and lowering the RMSE from 0.5 to *** enhancement is attributed to better representations of interannual,intraseasonal,and synoptic scales *** study offers a novel approach to correct global SST simulations and underscores its effectiveness across different time scales and primary dynamical modes.

关键词： generative adversarial networks model bias deep learning El Niño-Southern Oscillation marine heatwaves