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Intramolecular Induction of Asymmetric Darzen's Condensation of Aldehydes with Chiral α-Chloroacetates

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Chinese Chemical Letters 1999年第6期10卷 441-442页

作者： Guo Bin HUANG Gan Feng CAO ke met wu Liang HUANG(Institute of Materia Medica. Chinese Academy of Medical Sciences & Peking Union Medical College.Xian Nong Tan Street. Beijing 100050) Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 1 Xian Nong Tan Street China

The asymmetric Darzen's condensation of aldehydes with a-chloroacetates of somenaturally occurring or synthetic chiral alcohols was described. The de% of products fell over therange of 4. 78% to 99%.

关键词： Asymmetric Darzen's condensation chiral α-chloroacetates

Highly mass activity electrocatalysts with ultralow Pt loading on carbon black for hydrogen evolution reaction

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International Journal of Minerals,metallurgy and Materials 2025年第1期32卷 182-190页

作者： Shaorou ke Yajing Zhao Xin Min Yanghong Li Ruiyu Mi Yangai Liu Xiaowen wu Minghao Fang Zhaohui Huang Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid WastersNational Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of Geosciences(Beijing)Beijing 100083China

Pt-based nanocatalysts offer excellent prospects for various ***,the low loading of Pt with excellent performance for efficient and stable nanocatalysts still presents a considerable *** this study,nanocatalysts with ultralow Pt content,excellent performance,and carbon black as support were prepared through in-situ ***~2-nm particles uniformly and stably dispersed on carbon black because of the strong s-p-d orbital hybridizations between carbon black and Pt,which suppressed the agglomeration of Pt *** unique structure is beneficial for the hydrogen evolution *** catalysts exhibited remarkable catalytic activity for hydrogen evolution reaction,exhibiting a potential of 100 mV at 100 mA·cm^(-2),which is comparable to those of commercial Pt/C *** activity(1.61 A/mg)was four times that of a commercial Pt/C catalyst(0.37 A/mg).The ultralow Pt loading(6.84wt%)paves the way for the development of next-generation electrocatalysts.

关键词： hydrogen evolution reaction ultralow platinum in-situ synthesis ultrasound

Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis

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Neural Regeneration Research 2025年第4期20卷 1103-1123页

作者： Xiahong Tang Nan Zheng Qingming Lin Yan You Zheng Gong Yangping Zhuang Jiali wu Yu Wang Hanlin Huang Jun ke Feng Chen Shengli Clinical Medical College of Fujian Medical University Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Emergency Fujian Provincial HospitalFuzhouFujian ProvinceChina Fujian Provincial key Laboratory of Emergency Medicine FuzhouFujian ProvinceChina The Second Department of Intensive Care Unit Fujian Provincial Hospital South BranchFuzhouFujian ProvinceChina

Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological *** preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are *** this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB ***,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by *** results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these *** conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning.

关键词： bone marrow–derived mesenchymal stem cells cardiac arrest cardiac resuscitation hypoxic preconditioning liver isoform of phosphofructokinase mitochondria neuroinflammation oxidative stress pyroptosis reactive oxygen species

The compound(E)-2-(3,4-dihydroxystyryl)-3-hydroxy-4H-pyran-4-one alleviates neuroinflammation and cognitive impairment in a mouse model of Alzheimer's disease

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Neural Regeneration Research 2025年第11期20卷 3330-3344页

作者： Xueyan Liu Wei wu Xuejuan Li Chengyan Wang ke Chai Fanru Yuan Huijuan Zheng Yuxing Yao Chenlu Li Zu-Cheng Ye Daijun Zha Department of Medicinal Chemistry School of PharmacyFujian Medical UniversityFuzhouFujian ProvinceChina Fujian Provincial key Laboratory of Brain Aging and Neurodegenerative Diseases School of Basic Medical SciencesFujian Medical UniversityFuzhouFujian ProvinceChina Institute of Laboratory Animal Center Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Neurosurgery Neurosurgery Research InstituteThe First Affiliated HospitalFujian Medical UniversityFuzhouFujian ProvinceChina Department of Hyperbaric Oxygen National Regional Medical CenterBinhai Campus of the First Affiliated HospitalFujian Medical UniversityFuzhouFujian ProvinceChina

Previous studies have shown that the compound(E)-2-(3,4-dihydroxystyryl)-3-hydroxy-4H-pyran-4-one(D30),a pyromeconic acid derivative,possesses antioxidant and anti-inflammatory properties,inhibits amyloid-β aggregation,and alleviates scopolamine-induced cognitive impairment,similar to the phase Ⅲ clinical drug *** this study,we established a mouse model of Alzheimer's disease via intracerebroventricular injection of fibrillar amyloid-β to investigate the effect of D30 on fibrillar amyloid-β-induced *** results showed that D30 alleviated fibrillar amyloid-β-induced cognitive impairment,promoted fibrillar amyloid-β clearance from the hippocampus and cortex,suppressed oxidative stress,and inhibited activation of microglia and astrocytes.D30 also reversed the fibrillar amyloid-β-induced loss of dendritic spines and synaptic protein ***,we demonstrated that exogenous fibrillar amyloid-βintroduced by intracerebroventricular injection greatly increased galectin-3 expression levels in the brain,and this increase was blocked by *** the role of D30 in clearing amyloid-β,inhibiting neuroinflammation,protecting synapses,and improving cognition,this study highlights the potential of galectin-3 as a promising treatment target for patients with Alzheimer's disease.

关键词： Alzheimer's disease amyloid-β astrocyte cognitive impairment D30 dendritic spines galectin-3 microglia neuroinflammation neuron

Activatable chemiluminescence probe based on four-arm PEGconjugated-pyropheophorbide-a for in vivo autofluorescence-free imaging of peroxynitrite

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Science China Chemistry 2025年

作者： Jianmei ke Lei Ding Ronggui Lian Cheng Zheng Wenjun Li Aixian Zheng Yupeng Sun Ming wu Yongyi Zeng Xiaolong Liu Maochun Hong Xiaolong Zhang The United Innovation of Mengchao Hepatobiliary Technology key Laboratory of Fujian Province Mengchao Hepatobiliary Hospital of Fujian Medical University Ganjiang Innovation Academy Chinese Academy of Sciences School of Rare Earths University of Science and Technology of China College of Chemistry Fuzhou University State key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Peroxynitrite（ONOO-） is a highly reactive nitrogen species that plays pivotal roles in cell signal transduction and physiological or pathological progresses. However, commonly used ONOO-optical imaging probes are still hampered by high background/autofluorescence（fluorescence probe）, short emission wavelength, or poor selectivity in the case of chemiluminescence. Herein,we report a facile method to prepare an activatable chemiluminescence probe（PPA-PEG） with good biocompatibility and functionality for in vivo autofluorescence-free imaging of ONOO-. The PPA-PEG consists of pyropheophorbide-a（PPA）, a typical deep red photosensitizer that acts as both the recognition and signaling element, and 4-arm poly（ethylene glycol）(4-arm PEG), which improves the biosafety and water solubility of probe. These components can self-assemble into nanoparticles（namely PPA-PEG nanoprobe） in aqueous solution. The PPA-PEG nanoprobe showed an ultra-low chemiluminescence signal before interacting with ONOO-, but exhibited good selectivity, high sensitivity and a fast response toward ONOO-. The PPAPEG was successfully applied to image cellular ONOO-changes, as well as the endogenous ONOO-changes in inflammation models and subcutaneous or orthotopic hepatocellular carcinoma（HCC） tumors models in living mice. In vitro and in vivo studies verified the good detection and imaging capabilities of PPA-PEG for peroxynitrite, demonstrating suitable tissue penetration and a high signal-to-background ratio（SBR）. Thus, our nanoprobe can serve as a valuable activatable chemiluminescence imaging tool for studying important peroxynitrite-related chemical and biological applications.

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采用耗能装配节点的榫卯木构架抗震性能有限元分析

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地震工程学报 2025年第1期47卷 10-21页

作者：吴忠铁张轲解宁赵城吴为西北民族大学土木工程学院甘肃兰州730030

针对榫卯木构架常规梁柱榫卯节点的缺陷,提出一种榫卯木构架的梁柱耗能装配节点。为研究该耗能装配节点对木构架抗震性能的影响,利用有限元软件ABAQUS建立带有全钢耗能装配节点、橡胶柔性耗能装配节点、无加固的榫卯式节点三种不同类型... 详细信息

针对榫卯木构架常规梁柱榫卯节点的缺陷,提出一种榫卯木构架的梁柱耗能装配节点。为研究该耗能装配节点对木构架抗震性能的影响,利用有限元软件ABAQUS建立带有全钢耗能装配节点、橡胶柔性耗能装配节点、无加固的榫卯式节点三种不同类型榫卯木构架的有限元模型,并进行单调荷载加载分析和低周反复加载分析,主要研究这三类榫卯木构架模型的破坏特征、滞回曲线、骨架曲线、承载力及耗能能力等力学性能;同时,利用能力谱曲线和需求谱曲线,采用性能点探讨三类木构架的抗震性能。结果表明,与原榫卯木构架相比,该耗能装配节点能够有效地调整和控制木构架的破坏模式,增强梁柱节点的非线性力学性能,显著提高榫卯木构架的整体抗震性能。

关键词：榫卯木构架耗能装配节点力学性能性能点抗震性能

Unlocking the potential of spatial transcriptomics with custom microfluidic chips

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Science China Life Sciences 2025年

作者： Bingqi wu Yuan Gao China National Center for Bioinformation Beijing Institute of Genomics Chinese Academy of Sciences University of Chinese Academy of Sciences

Spatial transcriptomics technique detects RNA sequences (St?hl et al.,2016) and quantifies their expression in the positional context (ke et al.,2013),which can provide important information such as cell heterogeneity,cell developmental trajectory,differential gene expression between tissue regions or *** date,it is becoming a powerful tool for exploring tumorigenesis (Ren et al.,2023),cerebral neurodevelopment (Shi et al.,2023),embryonic development(Arutyunyan et al.,2023),and other biological ***-dimensional(3D) spatial transcriptome typically requires stacking multiple tissue slices to obtain a 3D atlas (Schott et al.,2024);therefore it prefers a method that meets high throughput,large sample sizes,and affordable cost to cover large regions of the ***,the lack of a single method that meets all of these requirements limits large-scale application of 3D spatial transcriptomics.

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第一性原理对M@B_(12)N_(12)(M=Sc-Zn)团簇结构和性质的研究

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原子与分子物理学报 2025年第4期42卷 93-99页

作者：张颂程露吴学科凯里学院理学院凯里556011

利用基于密度泛函理论的第一性原理对M@B_(12)N_(12)(M=Sc-Zn)团簇的几何、电子结构,电偶极性和红外吸收光谱进行详细的研究.结果显示:当B_(12)N_(12)团簇内嵌过渡金属原子后,虽然结构稳定性稍稍降低,但其化学活性得到提高,摩尔体积明... 详细信息

利用基于密度泛函理论的第一性原理对M@B_(12)N_(12)(M=Sc-Zn)团簇的几何、电子结构,电偶极性和红外吸收光谱进行详细的研究.结果显示:当B_(12)N_(12)团簇内嵌过渡金属原子后,虽然结构稳定性稍稍降低,但其化学活性得到提高,摩尔体积明显增大.过渡金属原子与B_(12)N_(12)结合的过程中,除Cu和B原子外,剩余金属与N原子的Mulliken电荷出现负值.另外,金属原子的加入,不仅增加电偶极矩和极化率的值,还促使其红外吸收光谱发生红移.

关键词：团簇结构性质第一性原理

2011—2020年广州市肺结核死亡趋势及年龄-时期-队列模型分析

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中国防痨杂志 2025年第1期47卷 44-50页

作者：李雪秋刘群唐科吴迪广州市胸科医院结核病防治所一分所广州510095 广东省生物制品与药物研究所药理研究室广州510440 广州市疾病预防控制中心慢性非传染性疾病预防控制部广州510440 广东医科大学公共卫生学院东莞523808

目的:分析2011—2020年广州市肺结核患者的死亡情况和死亡率变化趋势,为制定防控策略和措施提供科学依据。方法:采用Joinpoint回归模型分析2011—2020年广州市全年龄段人群肺结核死亡率变化趋势,并计算年度变化百分比(annual percent ch... 详细信息

目的:分析2011—2020年广州市肺结核患者的死亡情况和死亡率变化趋势,为制定防控策略和措施提供科学依据。方法:采用Joinpoint回归模型分析2011—2020年广州市全年龄段人群肺结核死亡率变化趋势,并计算年度变化百分比(annual percent change,APC)和平均年度变化百分比(average annual percent change,AAPC);使用年龄-时期-队列模型分析广州市20~85岁人群肺结核死亡风险的年龄、时期和队列效应。结果:广州市2011—2020年报告肺结核死亡患者2144例,年均报告标化死亡率为2.57/10万;男性肺结核标化死亡率为4.19/10万,约为女性标化死亡率(0.96/10万)的4.4倍。10年间广州市肺结核年龄标化死亡率总体呈现下降趋势,AAPC为-4.15%(95%CI:-6.41%~-1.85%,P=0.003);其中,女性肺结核死亡率下降速度高于男性,AAPC分别为-6.72%(95%CI:-10.38%~-2.92%,P=0.004)和-3.55%(95%CI:-6.19%~-0.85%,P=0.017)。在不同年龄段人群中,0~49岁和≥65岁年龄段人群肺结核死亡率均呈现明显下降趋势,AAPC分别为-7.05%(95%CI:-11.52%~-2.34%,P=0.009)和-3.94%(95%CI:-6.22%~-1.62%,P=0.005)。年龄-时期-队列模型的年龄效应显示,随着年龄的增长,肺结核死亡风险不断上升,≥65岁人群尤为显著,发病率由66~67岁年龄组的2.93/10万增长至84~85岁年龄组的6.10/10万。时期效应显示,肺结核死亡风险随着时期的变化总体呈现下降趋势,相对危险度(risk ratio,RR)从2011—2012年时期组的1.35下降至2019—2020年时期组的0.81。队列效应显示,越晚出生的人群肺结核死亡风险越低,RR值从1926—1927年出生队列的5.91降低至1998—1999年出生队列的0.16。结论:广州市肺结核死亡率总体呈不断下降的趋势,但男性和女性肺结核死亡率差距较大。需重点关注男性和≥65岁年龄段的老年人群,并实施针对性的防控和治疗措施。

关键词：结核,肺死亡率回归分析队列研究