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Protective effects of combined Astragalus membranaceus and magnesium ions on global brain ischemia

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Neural Regeneration Research 2011年第15期6卷 1136-1140页

作者： yifeng Miao Bing Li Yuchang Lin Xiaojie Lu Bin wu Yongming Qiu Neuroscience Center Nanjing Medical University Affiliated Wuxi No. 2 Hospital Wuxi 214002 Jiangsu Province China Department of Neurosurgery Ren Ji Hospital Shanghai Jiao Tong University School of Medicine Shanghai 200127 China

The traditional Chinese herb Astragalus membranaceus is a well-known treatment for neurological diseases and is considered to exhibit anti-dementia properties.This study investigated the synergistic effects of magnesium ions and Astragalus membranaceus on global brain ischemia in rats.4＇-6-diamidino-2-phenylindole staining demonstrated that the number of living neurons was significantly greater in the rat hippocampus after administration of a combination of Astragalus membranaceus and magnesium,compared with a vehicle group,an Astragalus membranaceus alone group,and a magnesium alone group.Western blot assay revealed that cleaved Caspase-3 protein expression was significantly reduced in the rat hippocampus in the combined Astragalus membranaceus and magnesium group compared with the Astragalus membranaceus alone group and the magnesium alone group.The results suggested that the combination of Astragalus membranaceus and magnesium exhibits a stronger neuroprotective effect on global brain ischemia in rats compared with Astragalus membranaceus or magnesium alone.This effect was associated with decreased Caspase-3 expression.

关键词： global brain ischemia Astragalus membranaceus magnesium neuroprotection Caspase-3 neural regeneration

Regulators of alternative polyadenylation operate at the transition from mitosis to meiosis

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Journal of Genetics and Genomics 2017年第2期44卷 95-106页

作者： Lingjuan Shan Chan wu Di Chen Lei Hou Xin Li Lixia Wang Xiao Chu yifeng Hou Zhaohui Wang State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100102China The University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Computational Biology Chinese Academy of Sciences-Man Planck Partner Institute for Computational BiologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200031China State Key Laboratory of Plant Genomics and National Center for Plant Gene Research Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Key Laboratory of Cenetic Network Biology Collaborative Innovation Center of Genetics and DevelopmentInstitute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China

In the sexually reproductive organisms, gametes are produced by meiosis following a limited mitotic amplification. However, the intrinsic program switching cells from mitotic to meiotic cycle is unclear.Alternative polyadenylation（APA） is a highly conserved means of gene regulation and is achieved by the RNA 30-processing machinery to generate diverse 30 UTR profiles. In Drosophila spermatogenesis, we observed distinct profiles of transcriptome-wide 30 UTR between mitotic and meiotic cells. In mutant germ cells stuck in mitosis, 30 UTRs of hundreds of genes were consistently shifted. Remarkably, altering the levels of multiple 30-processing factors disrupted germline＇s progression to meiosis, indicative of APA＇s active role in this transition. An RNA-binding protein（RBP） Tut could directly bind 30 UTRs of 30-processing factors whose expressions were repressed in the presence of Tut-containing complex. Further,we demonstrated that this RBP complex could execute the repression post-transcriptionally by recruiting CCR4/Twin of deadenylation complex. Thus, we propose that an RBP complex regulates the dynamic APA profile to promote the mitosis-to-meiosis transition.

关键词： Germ cell Mitosis to meiosis Alternative polyadenylation RNA-binding protein 3＇UTR

Adoptively transferred donor IL-17-producing CD4^(+) T cells augment, but IL-17 alleviates, acute graft-versus-host disease

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Cellular & Molecular Immunology 2018年第3期15卷 233-245页

作者： yifeng Cai Shoubao Ma Yuejun Liu Huanle Gong Qiao Cheng Bo Hu Yan wu Xiao Yu Chen Dong Kai Sun Depei wu Haiyan Liu Department of Hematology Institute of Blood and Marrow TransplantationCollaborative Innovation Center of HematologyThe First Affiliated Hospital of Soochow UniversitySuzhou215006China Jiangsu Institute of Hematology and Key Laboratory of Thrombosis and Hemostasis Ministry of Health Suzhou215006China Institute for Immunology and School of Medicine Tsinghua University School of MedicineBeijing100084China Department of Hematology Henan Provincial People’s HospitalZhengzhou450003China Life Sciences Institute and Department of Microbiology and Immunology Immunology ProgrammeNational University of SingaporeSingapore117456Singapore Department of Hematology The Affiliated Hospital of Nantong UniversityNantong 226001China

The role of IL-17 and IL-17-producing CD4^(+) T cells in acute graft-versus-host disease(GVHD)has been controversial in recent mouse and human studies.We carried out studies in a murine acute GVHD model of fully major histocompatibility complex-mismatched myeloablative bone marrow transplantation.We showed that donor wild-type CD4^(+) T cells exacerbated acute GVHD compared with IL-17−/−CD4^(+) T cells,while IL-17 reduced the severity of acute GVHD.The augmentation of acute GVHD by transferred donor IL-17-producing CD4^(+) T cells was associated with increased Th1 responses,while IL-17 decreased the percentages of Th1 cells in the GVHD target organs.Furthermore,IL-17 reduced the infiltration of macrophages into the GVHD tissues.In vitro study showed that IL-17 could downregulate Th1 responses,possibly through inhibiting IL-12 production by donor macrophages.Depletion of macrophages in vivo diminished the protective effect of IL-17.Our results demonstrated the differential roles of adoptively transferred donor IL-17-producing CD4^(+) T cells and IL-17 in the same acute GVHD model.

关键词： aGVHD BMT CD4^(+)T cells IL-17 Th17 cells

Effects of Added HY Zeolite on the Catalytic Behavior of Pt/OMC-HY in the Hydrogenation of Naphthalene

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China Petroleum Processing & Petrochemical Technology 2019年第3期21卷 17-28页

作者： wu Bingfeng Yang Lina Li Jian Yang Xiaorong Huang yifeng Bai Jin College of Chemistry Chemical Engineering and Environmental Engineering Liaoning Shihua University

In this work,HY zeolites were embedded in the ordered mesoporous carbon(OMC)to prepare a support for a noble metal catalyst Pt/OMC-HY,and the hydrogenation of naphthalene to decalin was carried out over the catalyst.The results showed that Pt/OMC-HY-0.14(in which the mass ratio of HY to phenolic resin oligomer is 0.14)possessed much better catalyst performance than Pt/OMC,which was related to its proper surface acidity,hierarchical pore structure,metal dispersion,and the interaction between metal and support.Furthermore,Pt/OMC-HY-0.14 had better sulfur tolerance than Pt/OMC.In addition,the sulfur tolerance mechanism of Pt/OMC-HY-0.14 was studied,which revealed that the competitive adsorption of DBT on the metal sites with aromatics was the main reason for catalyst deactivation,and the improvement of sulfur tolerance could be achieved by the aid of the acidity of HY zeolite.Based on the acidity,the hydrogenation of DBT can be promoted obviously,and consequently the competitive adsorption of DBT on the metal sites can be reduced.

关键词： naphthalene hydrogenation HY zeolite mesoporous carbon sulfur tolerance hierarchical pore structure

初植和补植阔叶树对红壤丘陵区湿地松养分获取和转运的影响

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林业科学 2024年第1期60卷 47-57页

作者：夏成康林勇兰勇吴高洋王晟楠陈伏生江西农业大学林学院江西省森林培育重点实验室南昌330045 江西农业大学鄱阳湖流域森林生态系统保护与修复国家林业和草原局重点实验室南昌330045 江西官山国家级自然保护区管理局宜丰336300 江西省森林资源监测中心南昌330045

【目的】探究初植(同龄混植)和补植(异龄混植)阔叶树对湿地松养分获取和利用策略的影响,为湿地松林的科学管理提供参考。【方法】以种植于我国亚热带红壤丘陵区的湿地松林为对象,基于长期单种和混交试验平台,分别在林龄30年且立地条件... 详细信息

【目的】探究初植(同龄混植)和补植(异龄混植)阔叶树对湿地松养分获取和利用策略的影响,为湿地松林的科学管理提供参考。【方法】以种植于我国亚热带红壤丘陵区的湿地松林为对象,基于长期单种和混交试验平台,分别在林龄30年且立地条件相似的湿地松纯林、湿地松-木荷初植混交林、湿地松-木荷补植混交林(补植木荷14年)中构建5块20 m×20 m标准样地(共15块样地),采集湿地松标准木的根际土壤、细根、枝、新鲜叶和凋落叶样品,测定土壤和植物各器官的氮(N)、磷(P)含量,评估不同混交模式对根养分捕获能力、叶养分回收和树木养分转运的影响,揭示养分获取策略变化的驱动因素。【结果】混交阔叶树显著提高湿地松根际土壤的NH_4~+-N和矿质氮含量(P0.05);整体看,混交阔叶树提高湿地松各器官的N、P含量,其中初植混交效应比补植好。与纯林相比,初植混交林中湿地松根氮和磷捕获能力分别显著提高14.04%和46.16%,叶氮回收效率显著降低6.07%,磷回收效率显著提高15.49%。尽管补植阔叶树降低根养分捕获成本,但阔叶树根系抑制湿地松根系的养分捕获能力,导致补植混交林中湿地松根养分捕获能力和叶养分回收效率均无显著变化。此外,与纯林相比,初植混交林中湿地松运输根向枝、叶的N转运分别提高36.05%和15.61%,P转运分别降低35.13%和36.52%;补植混交林中N转运无显著变化,但运输根向枝、叶的P转运比在纯林分别降低53.21%和40.17%。【结论】混交阔叶树提高红壤丘陵区湿地松根际土壤和植株各器官的养分含量,改变湿地松养分获取策略,其中初植比补植更能促进湿地松的养分获取和利用。此外,养分在植物体内的转运过程可被检测,且反映根捕获和叶回收的权衡关系。

关键词：针阔混交林根捕获叶养分回收养分获取策略木荷

Quinim配体的探索及其在镍催化烯烃的不对称胺甲酰基-烷基化反应的应用

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有机化学 2023年第12期43卷 4239-4250页

作者：吴利城伍贤青曲景平陈宜峰华东理工大学化学与分子工程学院、费林加诺贝尔奖科学家联合研究中心、材料生物学与动态化学前沿科学中心上海200237

发展手性配体是不对称催化的核心任务之一.本工作报道了镍催化1,1-二取代烯烃衍生的胺甲酰氯与烷基碘代物的不对称还原胺甲酰基-烷基化反应,构建了一系列对映选择性富集的α,α-双烷基取代的吡咯烷酮化合物.通过对Quinim配体的广泛探索... 详细信息

发展手性配体是不对称催化的核心任务之一.本工作报道了镍催化1,1-二取代烯烃衍生的胺甲酰氯与烷基碘代物的不对称还原胺甲酰基-烷基化反应,构建了一系列对映选择性富集的α,α-双烷基取代的吡咯烷酮化合物.通过对Quinim配体的广泛探索,发现p-tolQuinim至1-NapQuinim配体的革新是该反应成功的关键,能以高收率、高对映选择性及出色的官能团容忍性得到多样的α-位含有季碳中心的γ-内酰胺化合物.此外,研究发现,新发展的Ni/1-NapQuinim催化体系也能提高α-单烷基取代γ-内酰胺的合成效率及对映选择性.

关键词： Quinim配体镍催化剂季碳手性中心 γ-内酰胺

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无人机小样本条件下遮挡和混淆目标识别方法

国防科技大学学报 2022年第4期44卷 13-21页

作者：吴立珍李宏男牛轶峰国防科技大学智能科学学院湖南长沙410073

针对无人机对地目标识别过程中的小样本问题以及目标存在的遮挡和混淆情况,提出了一种融合自注意力机制的小样本目标识别模型。在利用元学习思想获取小样本学习能力的基础上,将自注意力机制学习目标内部各部分之间的上下文依赖关系引入... 详细信息

针对无人机对地目标识别过程中的小样本问题以及目标存在的遮挡和混淆情况,提出了一种融合自注意力机制的小样本目标识别模型。在利用元学习思想获取小样本学习能力的基础上,将自注意力机制学习目标内部各部分之间的上下文依赖关系引入模型,从而增强目标表征能力,以解决遮挡和混淆情况下有效特征不足的难题。为验证模型效果,通过对基准数据集和无人机航拍数据进一步加工,构建了遮挡和混淆目标数据集,设置了不同的遮挡程度和背景混淆率。通过在不同数据集上的验证,并与深度学习模型对比,证明提出的模型具有更高的学习效率和识别正确率。

关键词：无人机小样本学习自注意力遮挡混淆目标识别

尼龙织物叠层橡胶支座压缩与压剪性能试验研究

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振动与冲击 2022年第18期41卷 150-156页

作者：吴宜峰张琰李爱群徐泓北京建筑大学土木与交通工程学院北京100044 东南大学土木工程学院南京210096

为了进一步将隔震技术推广应用于低矮村镇建筑,设计制作了一种低成本尼龙织物叠层橡胶支座,并对其进行了竖向压缩与压剪试验。结果表明:支座的竖向刚度较叠层钢板橡胶支座明显偏小,但其竖向阻尼比可达7%;支座压剪滞回曲线饱满,残余位移... 详细信息

为了进一步将隔震技术推广应用于低矮村镇建筑,设计制作了一种低成本尼龙织物叠层橡胶支座,并对其进行了竖向压缩与压剪试验。结果表明:支座的竖向刚度较叠层钢板橡胶支座明显偏小,但其竖向阻尼比可达7%;支座压剪滞回曲线饱满,残余位移小;当剪应变较小时,支座因“翻滚”卷曲使其等效水平剪切刚度减小,但在大剪应变时,因橡胶材料硬化以及支座“全翻滚”变形,支座切线刚度明显增加;当支座在剪应变为300%时性能未见明显退化,但侧面出现小裂纹;随着剪应变增加,支座等效阻尼比在9%~13%当内呈现先减小后增大的规律。以上结果可为此类支座的进一步研究与工程应用提供参考。

关键词：尼龙织物叠层橡胶支座压缩试验压剪试验滞回曲线阻尼比

The promoting effect of low-level sulfidation in PdCuS nanoparticles catalyzed alkyne semihydrogenation

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Nano Research 2018年第9期11卷 4883-4889页

作者： Cai wu yifeng Chen Rongan Shen Wei Zhu Yue Gong Lin Gu Qing Peng Huifang Guo Wei He School ofPharmaceuticaISciences Tsinghua University Beijing 100084 China Department of Chemistry Tsinghua University Beijing 100084 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100050 China

硫来源的支持的效果是吸引人却糟糕听说的现象。此处，我们与硫粉末的不同数量学习了 PdCu 二金属的 nanoparticles (NP ) 的处理。低级 sulfidation 导致了由表面组成的 Pd30Cu10S9 NP 催化剂的产生充实的 Pd NP，电子缺乏的 Pd 和 Cu... 详细信息

硫来源的支持的效果是吸引人却糟糕听说的现象。此处，我们与硫粉末的不同数量学习了 PdCu 二金属的 nanoparticles (NP ) 的处理。低级 sulfidation 导致了由表面组成的 Pd30Cu10S9 NP 催化剂的产生充实的 Pd NP，电子缺乏的 Pd 和 Cu，以及零原子价硫。Pd30Cu10S9 NP 催化剂在炔属羟的 semihydrogenation 显示出显着地提高的活动和选择。我们的学习第一次在原子水平为硫的支持的效果揭示了一个可能的原因，建议在催化剂设计的新策略。

关键词：纳米技术纳米材料材料分析