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Arabidopsis cryptochrome 1 promotes stomatal development through repression of AGB1 inhibition of SPEECHLESS DNA-binding activity 被引量:2
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作者 Xiaoli Cao Pengbo Xu +11 位作者 Yao Liu Guangqiong Yang Minqing Liu Li Chen Yingyu Cheng Peng Xu Langxi Miao Zhilei Mao Wenxiu Wang Shuang Kou Tongtong Guo Hong‐Quan Yang 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2021年第11期1967-1981,共15页
Cryptochromes are blue light photoreceptors that mediate various light responses in plants and mammals. The heterotrimeric G-protein is known to regulate various physiological processes in plants and mammals. In Arabi... Cryptochromes are blue light photoreceptors that mediate various light responses in plants and mammals. The heterotrimeric G-protein is known to regulate various physiological processes in plants and mammals. In Arabidopsis, cryptochrome 1(CRY1) and the G-protein β subunit AGB1 act antagonistically to regulate stomatal development.The molecular mechanism by which CRY1 and AGB1 regulate this process remains unknown.Here, we show that Arabidopsis CRY1 acts partially through AGB1, and AGB1 acts through SPEECHLESS(SPCH), a master transcription factor that drives stomatal initiation and proliferation, to regulate stomatal development. We demonstrate that AGB1 physically interacts with SPCH to block the b HLH DNA-binding domain of SPCH and inhibit its DNA-binding activity. Moreover, we demonstrate that photoexcited CRY1 represses the interaction of AGB1 with SPCH to release AGB1 inhibition of SPCH DNA-binding activity, leading to the expression of SPCH-target genes promoting stomatal development. Taken together, our results suggest that the mechanism by which CRY1 promotes stomatal development involves positive regulation of the DNA-binding activity of SPCH mediated by CRY1 inhibition of the AGB1-SPCH interaction. We propose that the antagonistic regulation of SPCH DNA-binding activity by CRY1 and AGB1 may allow plants to balance light and G-protein signaling and optimize stomatal density and pattern. 展开更多
关键词 cryptochrome 1(CRY1) heterotrimeric G-proteinβ-subunit AGB1 SPEECHLESS dna-binding activity stomatal development
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Illusion of inactivity:Revisiting progressive multiple sclerosis treatment paradigms
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作者 Tal Ganz Tamir Ben-Hur 《Neural Regeneration Research》 2026年第3期1134-1135,共2页
Active inflammation in“inactive”progressive multiple sclerosis:Traditionally,the distinction between relapsing-remitting multiple sclerosis and progressive multiple sclerosis(PMS)has been framed as an inflammatory v... Active inflammation in“inactive”progressive multiple sclerosis:Traditionally,the distinction between relapsing-remitting multiple sclerosis and progressive multiple sclerosis(PMS)has been framed as an inflammatory versus degenerative dichotomy.This was based on a broad misconception regarding essentially all neurodegenerative conditions,depicting the degenerative process as passive and immune-independent occurring as a late byproduct of active inflammation in the central nervous system(CNS),which is(solely)systemically driven. 展开更多
关键词 inflammatory versus degenerative dichotomythis treatment paradigms illusion inactivity multiple sclerosis traditionallythe central nervous system cns which progressive multiple sclerosis active inflammation progressive multiple sclerosis pms
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Effects of calmodulin on DNA-binding activity of heat shock transcription factor in vitro 被引量:11
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作者 LIBing LIUHongtao 《Chinese Science Bulletin》 SCIE EI CAS 2003年第3期255-258,共4页
The DNA-binding activity of heat shocktranscription factor (HSF) was induced by heat shock (HS) of a whole cell extract. Addition of antiserum, specific toCaM, to a whole cell extract reduced bind of the HSF to the he... The DNA-binding activity of heat shocktranscription factor (HSF) was induced by heat shock (HS) of a whole cell extract. Addition of antiserum, specific toCaM, to a whole cell extract reduced bind of the HSF to the heat shock element (HSE) with maize, and the re-addition of CaM to the sample restored the activity of the HSF forbinding to HSE. In addition, DNA-binding activity of the HSF was also induced by directly adding CaM to a whole cell extract at non-HS temperature with maize. Similar resultswere obtained with wheat and tomato. Our observationprovide the first example of the involvement of CaM inregulation of the DNA-binding activity of the HSF. 展开更多
关键词 热休克转录因子 钙调蛋白 DNA结合 小麦 玉米 番茄 植物
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Copper complexes of anthrahydrazone bearing pyridyl side chain:Synthesis,crystal structure,anticancer activity,and DNA binding 被引量:1
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作者 HUANG Yao WU Yingshu +5 位作者 BAO Zhichun HUANG Yue TANG Shangfeng LIU Ruixue LIU Yancheng LIANG Hong 《无机化学学报》 北大核心 2025年第1期213-224,共12页
To expand the study on the structures and biological activities of the anthracyclines anticancer drugs and reduce their toxic side effects,the new anthraquinone derivatives,9‑pyridylanthrahydrazone(9‑PAH)and 9,10‑bisp... To expand the study on the structures and biological activities of the anthracyclines anticancer drugs and reduce their toxic side effects,the new anthraquinone derivatives,9‑pyridylanthrahydrazone(9‑PAH)and 9,10‑bispyridylanthrahydrazone(9,10‑PAH)were designed and synthesized.Utilizing 9‑PAH and 9,10‑PAH as promising anticancer ligands,their respective copper complexes,namely[Cu(L1)Cl_(2)]Cl(1)and{[Cu_(4)(μ_(2)‑Cl)_(3)Cl_(4)(9,10‑PAH)_(2)(DMSO)_(2)]Cl_(2)}_(n)(2),were subsequently synthesized,where the new ligand L1 is formed by coupling two 9‑PAH ligands in the coordination reaction.The chemical and crystal structures of 1 and 2 were elucidated by IR,MS,elemental analysis,and single‑crystal X‑ray diffraction.Complex 1 forms a mononuclear structure.L1 coordinates with Cu through its three N atoms,together with two Cl atoms,to form a five‑coordinated square pyramidal geometry.Complex 2 constitutes a polymeric structure,wherein each structural unit centrosymmetrically encompasses two five‑coordinated binuclear copper complexes(Cu1,Cu2)of 9,10‑PAH,with similar square pyramidal geometry.A chlorine atom(Cl_(2)),located at the symmetry center,bridges Cu1 and Cu1A to connect the two binuclear copper structures.Meanwhile,the two five‑coordinated Cu2 atoms symmetrically bridge the adjacent structural units via one coordinated Cl atom,respectively,thus forming a 1D chain‑like polymeric structure.In vitro anticancer activity assessments revealed that 1 and 2 showed significant cytotoxicity even higher than cisplatin.Specifically,the IC_(50)values of 2 against HeLa‑229 and SK‑OV‑3 cancer cell lines were determined to be(5.92±0.32)μmol·L^(-1)and(6.48±0.39)μmol·L^(-1),respectively.2 could also block the proliferation of HeLa‑229 cells in S phase and significantly induce cell apoptosis.In addition,fluorescence quenching competition experiments suggested that 2 might interact with DNA by an intercalative binding mode,offering insights into its underlying anticancer mechanism.CCDC:2388918,1;2388919,2. 展开更多
关键词 anthrahydrazone metal complex crystal structure anticancer activity cell apoptosis
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Passive activity enhances residual control ability in patients with complete spinal cord injury 被引量:2
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作者 Yanqing Xiao Mingming Gao +6 位作者 Zejia He Jia Zheng Hongming Bai Jia-Sheng Rao Guiyun Song Wei Song Xiaoguang Li 《Neural Regeneration Research》 SCIE CAS 2025年第8期2337-2347,共11页
Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these... Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface electromyography.In this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord injury.Eleven patients with chronic complete thoracic spinal cord injury were recruited.Surface electromyography data from eight major leg muscles were acquired and compared before and after the passive activity protocol.The results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of activation.Although the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically significant.These findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury. 展开更多
关键词 complete spinal cord injury cycle training epidural electrical stimulation motor training passive activity physiological state spinal cord circuit surface electromyography volitional control task
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Potent in vitro Interference of Fleroxacin in DNA-binding,Unwinding and ATPase Activities of Bloom Helicase 被引量:2
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作者 LUO Heng XU Hou Qiang +3 位作者 CHEN Xiang DING Mei YANG Qi Xin LI Kun 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第4期231-242,共12页
Objective To study the effect of fleroxacin (FLRX) on biological properties of Bloom (BLM) helicase catalytic core (BLM 642-2290 helicase) in vitro and the molecular mechanism of interaction between the two mol... Objective To study the effect of fleroxacin (FLRX) on biological properties of Bloom (BLM) helicase catalytic core (BLM 642-2290 helicase) in vitro and the molecular mechanism of interaction between the two molecules. Methods DNA-binding and unwinding activities of BLM 642-1290 helicase were assayed by fluorescence polarization and gel retardation assay under conditions that the helicase was subjected to different concentrations of FLRX. Effect of FLRX on helicase ATPase activity was analyzed by phosphorus-free assay based on a colorimetric estimation of ATP hydrolysis-produced inorganic phosphate. Molecular mechanism of interaction between the two molecules was assayed by ultraviolet and fluorescence spectra. Results The DNA unwinding and ATPase activities of BLM 642-1290 helicase were inhibited whereas the DNA-binding activity was promoted in vitro. A BLM-FLRX complex was formed through one binding site, electrostatic and hydrophobic interaction force. Moreover, the intrinsic fluorescence of the helicase was quenched by FLRX as a result of non-radioactive energy transfer. The biological activity of helicase was affected by FLRX, which may be through an allosteric mechanism and stabilization of enzyme conformation in low helicase activity state, disruption of the coupling of ATP hydrolysis to unwinding, and blocking helicase translocation on DNA strands. Conclusion FLRX may affect the biological activities and conformation of BLM 642-1290 helicase, and DNA helicase may be used as a promising drug target for some diseases. 展开更多
关键词 Biological activity BLM helicase FLEROXACIN Interaction mechanism
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New diterpenoids from Euphorbia wallichii with antioxidant activity 被引量:1
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作者 Yali Wang Juan Chen +4 位作者 Wenshuo Zheng Ziyan Gao Yuxin Gan Hua Li Lixia Chen 《Chinese Journal of Natural Medicines》 2025年第10期1248-1258,共11页
Thirteen novel diterpenoids,comprising seven tiglianes(walliglianes G−M,1−7),four rhamnofolanes(wallinofolanes A−D,8−11),and two daphnanes(wallaphnanes A and B,12 and 13),together with two known rhamnofolane diterpeno... Thirteen novel diterpenoids,comprising seven tiglianes(walliglianes G−M,1−7),four rhamnofolanes(wallinofolanes A−D,8−11),and two daphnanes(wallaphnanes A and B,12 and 13),together with two known rhamnofolane diterpenoids(euphorwallside H and euphorwallside I,14 and 15),were isolated and characterized from Euphorbia wallichii(E.wallichii).The chemical structures of these compounds were elucidated through nuclear magnetic resonance(NMR),mass spectrometry(MS),and quantum chemical calculations.Compounds 9 and 11 demonstrated protective effects against H2O2-induced BV-2 microglial cell damage.Molecular docking analyses indicated that compound 9 exhibited binding affinity to the anti-oxidant-related targets HMGCR,GSTP1,and SHBG. 展开更多
关键词 Euphorbia wallichii Tiglianes Rhamnofolanes Daphnanes Antioxidant activity
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Glutamatergic CYLD deletion leads to aberrant excitatory activity in the basolateral amygdala:association with enhanced cued fear expression
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作者 Huidong Li Faqin Li +8 位作者 Zhaoyi Chen Erwen Wu Xiaoxi Dai Danni Li Haojie An Shiyi Zeng Chunyan Wang Li Yang Cheng Long 《Neural Regeneration Research》 SCIE CAS 2025年第11期3259-3272,共14页
Neuronal activity,synaptic transmission,and molecular changes in the basolateral amygdala play critical roles in fear memory.Cylindromatosis(CYLD)is a deubiquitinase that negatively regulates the nuclear factor kappa-... Neuronal activity,synaptic transmission,and molecular changes in the basolateral amygdala play critical roles in fear memory.Cylindromatosis(CYLD)is a deubiquitinase that negatively regulates the nuclear factor kappa-B pathway.CYLD is well studied in non-neuronal cells,yet underinvestigated in the brain,where it is highly expressed.Emerging studies have shown involvement of CYLD in the remodeling of glutamatergic synapses,neuroinflammation,fear memory,and anxiety-and autism-like behaviors.However,the precise role of CYLD in glutamatergic neurons is largely unknown.Here,we first proposed involvement of CYLD in cued fear expression.We next constructed transgenic model mice with specific deletion of Cyld from glutamatergic neurons.Our results show that glutamatergic CYLD deficiency exaggerated the expression of cued fear in only male mice.Further,loss of CYLD in glutamatergic neurons resulted in enhanced neuronal activation,impaired excitatory synaptic transmission,and altered levels of glutamate receptors accompanied by over-activation of microglia in the basolateral amygdala of male mice.Altogether,our study suggests a critical role of glutamatergic CYLD in maintaining normal neuronal,synaptic,and microglial activation.This may contribute,at least in part,to cued fear expression. 展开更多
关键词 basolateral amygdala cued fear expression cylindromatosis deubiquitinase glutamate receptor 1 glutamatergic neuron microglial activation N-methyl-D-aspartate receptor 1 neuronal activation synaptic transmission
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Chaeglobol A,an unusual octocyclic sterol with antifungal activity from the marine-derived fungus Chaetomium globosum HBU-45 被引量:1
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作者 Yun-Feng Liu Hui-Fang Du +4 位作者 Ya-Hui Zhang Zhi-Qin Liu Xiao-Qian Qi Du-Qiang Luo Fei Cao 《Chinese Chemical Letters》 2025年第3期407-410,共4页
Chemical investigation of the marine-derived fungus Chaetomium globosum HBU-45 led to the discovery of chaeglobol A(1).Its structure was determined by spectroscopic analysis,computational electronic circular dichroism... Chemical investigation of the marine-derived fungus Chaetomium globosum HBU-45 led to the discovery of chaeglobol A(1).Its structure was determined by spectroscopic analysis,computational electronic circular dichroism(ECD)/optical rotatory dispersion(ORD)methods,and X-ray crystallography.Compound 1 represents a new skeleton with an uncommon 6/6/6/5/6/5/6/5 octacyclic system,which is presumably biosynthesized via a[4+2]cycloaddition and an enzymatic cyclization.Chaeglobol A(1)exhibited inhibitory activity against B.dothidea by destroying cell membrane integrity and causing oxidative damage within the cells. 展开更多
关键词 Marine-derived fungus Chaetomium globosum Octocyclic sterol Antifungal activity Single-crystal X-ray diffraction
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High-areal-capacity and long-life sulfde-based all-solid-state lithium battery achieved by regulating surface-to-bulk oxygen activity 被引量:4
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作者 Yanchen Liu Yang Lu +6 位作者 Zongliang Zhang Bin Xu Fangbo He Yang Liu Yongle Chen Kun Zhang Fangyang Liu 《Journal of Energy Chemistry》 2025年第2期795-807,I0017,共14页
Sulfide-based all-solid-state lithium batteries(ASSLBs) with nickel-rich oxide cathodes are emerging as primary contenders for the next generation rechargeable batteries,owing to their superior safety and energy densi... Sulfide-based all-solid-state lithium batteries(ASSLBs) with nickel-rich oxide cathodes are emerging as primary contenders for the next generation rechargeable batteries,owing to their superior safety and energy density.However,the all-solid-state batteries with nickel-rich oxide cathodes suffer from performance degradation due to the reactions between the highly reactive surface oxygen of the cathode and the electrolyte,as well as the instability of the bulk oxygen structure in the cathode.Herein,we propose a synergistic modification design scheme to adjust the oxygen activity from surface to bulk.The LiBO_(2)coating inhibits the reactivity of surface lattice oxygen ions.Meanwhile,Zr doping in the bulk phase forms strong Zr-O covalent bonds that stabilize the bulk lattice oxygen structure.The synergistic effect of these modifications prevents the release of oxygen,thus avoiding the degradation of the cathode/SE interface.Additionally,the regulation of surface-to-bulk oxygen activity establishes a highly stable interface,thereby enhancing the lithium ion diffusion kinetics and mechanical stability of the cathode.Consequently,cathodes modified with this synergistic strategy exhibit outstanding performance in sulfide-based ASSLBs,including an ultra-long cycle life of 100,000 cycles,ultra-high rate capability at 45C,and 85% high active material content in the composite cathode.Additionally,ASSLB exhibits stable cycling under high loading conditions of 82.82 mg cm^(-2),achieving an areal capacity of 17.90 mA h cm^(-2).These encouraging results pave the way for practical applications of ASSLBs in fast charging,long cycle life,and high energy density in the future. 展开更多
关键词 Zr4+doping LiBO_(2)coating Surface-to-bulk Oxygen activity Interface stability Nickel-rich oxide cathodes All-solid-state batteries
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Deciphering Water Oxidation Catalysts:The Dominant Role of Surface Chemistry over Reconstruction Degree in Activity Promotion
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作者 Li An Jianyi Li +7 位作者 Yuanmiao Sun Jiamin Zhu Justin Zhu Yeow Seow Hong Zhang Nan Zhang Pinxian Xi Zhichuan J.Xu Chun‑Hua Yan 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期340-354,共15页
Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution reaction.The surface reconstruction has been widely observed in perovskite catalysts,and the reconstruction degree has ... Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution reaction.The surface reconstruction has been widely observed in perovskite catalysts,and the reconstruction degree has been often correlated with the activity enhancement.Here,a systematic study on the roles of Fe substitution in activation of perovskite LaNiO_(3)is reported.The substituting Fe content influences both current change tendency and surface reconstruction degree.LaNi_(0.9)Fe_(0.1)O_(3)is found exhibiting a volcano-peak intrinsic activity in both pristine and reconstructed among all substituted perovskites in the LaNi_(1-x)Fe_(x)O_(3)(x=0.00,0.10,0.25,0.50,0.75,1.00)series.The reconstructed LaNi_(0.9)Fe_(0.1)O_(3)shows a higher intrinsic activity than most reported NiFe-based catalysts.Besides,density functional theory calculations reveal that Fe substitution can lower the O 2p level,which thus stabilize lattice oxygen in LaNi0.9Fe0.1O3 and ensure its long-term stability.Furthermore,it is vital interesting that activity of the reconstructed catalysts relied more on the surface chemistry rather than the reconstruction degree.The effect of Fe on the degree of surface reconstruction of the perovskite is decoupled from that on its activity enhancement after surface reconstruction.This finding showcases the importance to customize the surface chemistry of reconstructed catalysts for water oxidation. 展开更多
关键词 Oxygen evolution reaction Perovskite oxides DOPING activation and reconstruction
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Curvularin derivatives from hydrothermal vent sediment fungus Penicillium sp.HL-50 guided by molecular networking and their antiinflammatory activity 被引量:1
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作者 Chunxue Yu Zixuan Xia +6 位作者 Zhipeng Xu Xiyang Tang Wenjuan Ding Jihua Wei Danmei Tian Bin Wu Jinshan Tang 《Chinese Journal of Natural Medicines》 2025年第1期119-128,共10页
Guided by molecular networking,nine novel curvularin derivatives(1-9)and 16 known analogs(10-25)were isolated from the hydrothermal vent sediment fungus Penicillium sp.HL-50.Notably,compounds 5-7 represented a hybrid ... Guided by molecular networking,nine novel curvularin derivatives(1-9)and 16 known analogs(10-25)were isolated from the hydrothermal vent sediment fungus Penicillium sp.HL-50.Notably,compounds 5-7 represented a hybrid of curvularin and purine.The structures and absolute configurations of compounds 1-9 were elucidated via nuclear magnetic resonance(NMR)spectroscopy,X-ray diffraction,electronic circular dichroism(ECD)calculations,^(13)C NMR calculation,modified Mosher's method,and chemical derivatization.Investigation of anti-inflammatory activities revealed that compounds 7-9,11,12,14,15,and 18 exhibited significant suppressive effects against lipopolysaccharide(LPS)-induced nitric oxide(NO)production in murine macrophage RAW264.7 cells,with IC_(50)values ranging from 0.44 to 4.40μmol·L^(-1).Furthermore,these bioactive compounds were found to suppress the expression of inflammation-related proteins,including inducible NO synthase(i NOS),cyclooxygenase-2(COX-2),NLR family pyrin domain-containing protein 3(NLRP3),and nuclear factor kappa-B(NF-κB).Additional studies demonstrated that the novel compound 7 possessed potent antiinflammatory activity by inhibiting the transcription of inflammation-related genes,downregulating the expression of inflammation-related proteins,and inhibiting the release of inflammatory cytokines,indicating its potential application in the treatment of inflammatory diseases. 展开更多
关键词 Penicillium sp.HL-50 Curvularin derivatives Molecular networking Anti-inflammatory activity
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On-line HPLC-DAD coupled with ESI-IT-TOF-MS and fluorescence detection to identify DNA-binding compounds from Lithospermum erythrorhizon using acridine orange as the fluorescence probe
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作者 黄文芳 张藏蔓 +3 位作者 李森森 梁毅 王弘 陈世忠 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2015年第9期581-590,共10页
We have developed an on-line detection method using acridine orange as the fluorescence probe and applied this method to rapidly identify active compounds in herbal medicines. This on-line method was equipped with a h... We have developed an on-line detection method using acridine orange as the fluorescence probe and applied this method to rapidly identify active compounds in herbal medicines. This on-line method was equipped with a high-performance liquid chromatography tandem diode array detector, electrospray ionization-ion-trap time-of-flight mass spectrometry and DNA- acridine orange fluorescence detection (HPLC-DAD-MSn-DNA-AO-FLD). A large amount of information could be simultaneously obtained during one run, which included HPLC fingerprint, ultraviolet spectra, total ion chromatograms, MSn data of high-resolution mass spectrometry and activity profile of each compound binding with DNA. The method also provided information on structureactivity relationships and mechanism of interaction. We used this on-line method to identify five DNA-binding activity components from Lithospermum erythrorhizon sample for the first time. The result showed that the parent nucleus of shikonin derivatives could bind with DNA. The structure-activity relationship showed that the parent nucleus of shikonin derivatives plays a major role in DNA binding, not the carboxyl group on the side chain. This simple, rapid, high precision and good stability on-line method should be useful for compound separation, structural identification and screening of DNA-binding compounds in herbal medicines. 展开更多
关键词 ON-LINE Lithospermum erythrorhizon Acridine orange DNA dna-binding activity
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One New Guaianolide Sesquiterpenoid with Potential Anti-inflammatory Activity from Ainsliaea glabra.
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作者 Qiu Xiong Li Huijuan +5 位作者 Tang Yanling Xu Yaojun Li Na Li Xiaoli Zhang Xingjie Xiao Weilie 《有机化学》 北大核心 2025年第8期3028-3032,共5页
Eight sesquiterpenes were isolated from Ainsliaea glabra.Among them,a new guaianolide sesquiterpenoid,named ainsglaolide A(1),and seven known sesquiterpenoids 2~8 were identified.Compound 1 was a novel guaianolide ses... Eight sesquiterpenes were isolated from Ainsliaea glabra.Among them,a new guaianolide sesquiterpenoid,named ainsglaolide A(1),and seven known sesquiterpenoids 2~8 were identified.Compound 1 was a novel guaianolide sesquiterpenoid featuring a rare six-membered lactone ring formed between C-4 and C-15.The new compound structure was elucidated by HRESI-MS and NMR spectroscopy,as well as electrostatic circular dichroism(ECD)calculations were used to further confirm the absolute of 1.Anti-inflammatory activity tests were conducted on the separated compounds,indicating that compound 1 had significant inhibitory effect on NLRP3 inflammasome with an IC_(50) value of 1.86μmol/L. 展开更多
关键词 Ainsliaea glabra SESQUITERPENES anti-inflammatory activity
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Acute Inflammatory Pain Induces Sex-different Brain Alpha Activity in Anesthetized Rats Through Optically Pumped Magnetometer Magnetoencephalography
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作者 MIAO Meng-Meng REN Yu-Xuan +5 位作者 WU Wen-Wei ZHANG Yu PAN Chen LIN Xiang-Hong LIN Hui-Dan CHEN Xiao-Wei 《生物化学与生物物理进展》 北大核心 2025年第1期244-257,共14页
Objective Magnetoencephalography(MEG),a non-invasive neuroimaging technique,meticulously captures the magnetic fields emanating from brain electrical activity.Compared with MEG based on superconducting quantum interfe... Objective Magnetoencephalography(MEG),a non-invasive neuroimaging technique,meticulously captures the magnetic fields emanating from brain electrical activity.Compared with MEG based on superconducting quantum interference devices(SQUID),MEG based on optically pump magnetometer(OPM)has the advantages of higher sensitivity,better spatial resolution and lower cost.However,most of the current studies are clinical studies,and there is a lack of animal studies on MEG based on OPM technology.Pain,a multifaceted sensory and emotional phenomenon,induces intricate alterations in brain activity,exhibiting notable sex differences.Despite clinical revelations of pain-related neuronal activity through MEG,specific properties remain elusive,and comprehensive laboratory studies on pain-associated brain activity alterations are lacking.The aim of this study was to investigate the effects of inflammatory pain(induced by Complete Freund’s Adjuvant(CFA))on brain activity in a rat model using the MEG technique,to analysis changes in brain activity during pain perception,and to explore sex differences in pain-related MEG signaling.Methods This study utilized adult male and female Sprague-Dawley rats.Inflammatory pain was induced via intraplantar injection of CFA(100μl,50%in saline)in the left hind paw,with control groups receiving saline.Pain behavior was assessed using von Frey filaments at baseline and 1 h post-injection.For MEG recording,anesthetized rats had an OPM positioned on their head within a magnetic shield,undergoing two 15-minute sessions:a 5-minute baseline followed by a 10-minute mechanical stimulation phase.Data analysis included artifact removal and time-frequency analysis of spontaneous brain activity using accumulated spectrograms,generating spectrograms focused on the 4-30 Hz frequency range.Results MEG recordings in anesthetized rats during resting states and hind paw mechanical stimulation were compared,before and after saline/CFA injections.Mechanical stimulation elevated alpha activity in both male and female rats pre-and post-saline/CFA injections.Saline/CFA injections augmented average power in both sexes compared to pre-injection states.Remarkably,female rats exhibited higher average spectral power 1 h after CFA injection than after saline injection during resting states.Furthermore,despite comparable pain thresholds measured by classical pain behavioral tests post-CFA treatment,female rats displayed higher average power than males in the resting state after CFA injection.Conclusion These results imply an enhanced perception of inflammatory pain in female rats compared to their male counterparts.Our study exhibits sex differences in alpha activities following CFA injection,highlighting heightened brain alpha activity in female rats during acute inflammatory pain in the resting state.Our study provides a method for OPM-based MEG recordings to be used to study brain activity in anaesthetized animals.In addition,the findings of this study contribute to a deeper understanding of pain-related neural activity and pain sex differences. 展开更多
关键词 MAGNETOENCEPHALOGRAPHY PAIN sex differences alpha activity INFLAMMATION
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Praseodymium-organic framework with 4,4′-oxybis(benzoic acid):Rare broken layer structure,antibacterial activity,and sensing for Cd^(2+)ions
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作者 CUI Peipei ZHENG Yawen +2 位作者 LI Pan GUAN Peiyan QIAN Zhaohong 《无机化学学报》 北大核心 2025年第8期1641-1649,共9页
A novel 3D metal-organic framework(MOF)[Pr_(2)(L)_(3)(H_(2)O)5·H_(2)O]n(Pr-1),(H_(2)L=4,4'-oxybis(benzoic acid))with a rare structure of broken layer net,was constructed under the condition of solvothermal sy... A novel 3D metal-organic framework(MOF)[Pr_(2)(L)_(3)(H_(2)O)5·H_(2)O]n(Pr-1),(H_(2)L=4,4'-oxybis(benzoic acid))with a rare structure of broken layer net,was constructed under the condition of solvothermal synthesis.The struc-ture and crystal net were analyzed and characterized.This rod net of Pr-1 is new to both RCSR and ToposPro data-bases,and is named as rn-12 as suggested.Due to the luminescent properties of H_(2)L and Pr(Ⅲ),the solid-state fluo-rescence property and sensing performance(solvents and metal ions)of Pr-1 were investigated.The sensing experi-ments indicated that Pr-1 could act as a fluorescence sensor to detect Cd^(2+)ions with good sensitivity.In addition,antibacterial activities show that Pr-1 exhibited stronger antibacterial activity against Escherichia coli(E.coli),Staphylococcus aureus(S.aureus),and Bacillus subtilis(B.subtilis)compared to synthetic materials. 展开更多
关键词 dicarboxylate ligand crystal net luminescence sensing antibacterial activity
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The wearable landscape: Issues pertaining to the validation of the measurement of 24-h physical activity, sedentary, and sleep behavior assessment 被引量:2
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作者 Marco Giurgiu Birte von Haaren-Mack +16 位作者 Janis Fiedler Simon Woll Alexander Burchartz Simon Kolb Sascha Ketelhut Claudia Kubica Carina Nigg Irina Timm Maximiliane Thron Steffen Schmidt Kathrin Wunsch Gerhard Muller Claudio RNigg Alexander Woll Markus Reichert Ulrich Ebner-Priemer Johannes BJ Bussmann 《Journal of Sport and Health Science》 2025年第3期131-139,共9页
The ongoing revolution in information technology is reshaping human life. In the realm of health behavior, wearable technology emerges as a leading digital solution,capturing physical behaviors (i.e., physical activit... The ongoing revolution in information technology is reshaping human life. In the realm of health behavior, wearable technology emerges as a leading digital solution,capturing physical behaviors (i.e., physical activity, sedentary habits, sleep patterns) within the 24-h cycle of daily life. Wearables are applied in research, clinical practice, and as lifestyle devices;most obvious, they promise to be a key element for increasing human physical activity, one of the biggest health challenges nowadays. 展开更多
关键词 increasing human physical activityone lifestyle devicesmost validation studies health behaviorwearable technology revolution information technology wearable technology physical activity physical behaviors iephysical
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Strategies for balancing catalytic activity and stability in lithium-sulfur batteries
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作者 PENG Lin-kai SHI Ji-wei +3 位作者 CAO Yun LAN Jia-qi GENG Chuan-nan LV Wei 《新型炭材料(中英文)》 北大核心 2025年第4期889-908,共20页
Lithium-sulfur(Li-S)batteries have great promise for next-generation energy storage devices due to the high theoretical specific capacity(1675 mAh g^(-1))of sulfur with chemical conversion for charge storage.However,t... Lithium-sulfur(Li-S)batteries have great promise for next-generation energy storage devices due to the high theoretical specific capacity(1675 mAh g^(-1))of sulfur with chemical conversion for charge storage.However,their practical use is hindered by the slow redox kinetics of sulfur and the“shuttle effect”arising from dissolved lithium polysulfides(LiPSs).In recent years,various carbon-based materials have served as sulfur hosts and catalysts for accelerating sulfur conversion redox kinetics and alleviating LiPS shuttling.However,they often suffer from irreversible passivation and structural changes that destroy their long-term performance.We consider the main problems limiting their stability,including excessive LiPS adsorption,passivation by insulating Li2S,and surface reconstruction,and clarify how these factors lead to capacity fade.We then outline effective strategies for achieving long-term sulfur catalysis,focusing on functional carbon,such as designing suitable carbon-supported catalyst interfaces,creating well-distributed active sites,adding cocatalysts to improve electron transfer,and using carbon-based protective layers to suppress unwanted side reactions.Using this information should enable the development of stable,high-activity catalysts capable of long-term operation under practical conditions in Li-S batteries. 展开更多
关键词 Lithium-sulfur batteries CATALYSIS Catalyst poisoning Catalytic activity Catalytic stability
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Research progress on the effects of sedentary behavior and physical activity on diabetes mellitus
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作者 CHEN Qi LI Chuan-Fen JING Wen 《生理学报》 北大核心 2025年第1期62-74,共13页
Diabetes mellitus(DM)has become one of the most serious and common chronic diseases around the world,leading to various complications and a reduction in life expectancy.Increased sedentary behavior(SB)and decreased ph... Diabetes mellitus(DM)has become one of the most serious and common chronic diseases around the world,leading to various complications and a reduction in life expectancy.Increased sedentary behavior(SB)and decreased physical activity(PA)are important contributors to the rising prevalence of DM.This article reviews the research progress on the pathogenesis of DM,the effects of SB and PA on the risk of DM,aiming to explore the influence of different PA intensities,amounts,frequencies,durations and types on the incidence of DM.Research has shown that blood glucose levels tend to increase with the prolongation of SB.Within a certain range,PA intensity and PA amount are negatively correlated with the risk of DM;Performing PA for more than 3 days per week maintains normal glucose tolerance and lower blood pressure;Engaging in 150–300 min of moderate intensity exercise or 75–150 min of high-intensity exercise per week reduces the risk of DM;PA during leisure time reduces the risk of DM,while PA during work increases the risk of DM;Both aerobic training and resistance training reduce the risk of DM,and the combination of the two training methods produces better benefits;Various types of exercises,such as cycling,soccer,aerobics,yoga,tai chi,all reduce the risk of DM.In summary,prolonged SB increases the risk of DM,while appropriate PA reduces the risk of DM.As the intensity,amount,and frequency of PA increase,the effect of reducing DM risk becomes more significant.Different exercise methods have different effects on reducing DM risk. 展开更多
关键词 sedentary behavior physical activity diabetes mellitus sports rehabilitation health promotion
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Single-molecule investigation of the impacts of fluorescent DNA-binding proteins on DNA mechanical properties
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作者 Yaxi Cheng Shang Gao +2 位作者 Xianqi Ye Chuang Tan Jie Ma 《Chinese Physics B》 2025年第8期457-463,共7页
DNA imaging and visualization techniques are crucial in biological experiments and have also emerged as a powerful method for single-molecule studies.Traditional intercalating dyes(e.g.,SYTOX,EtBr,GelRed)can stain DNA... DNA imaging and visualization techniques are crucial in biological experiments and have also emerged as a powerful method for single-molecule studies.Traditional intercalating dyes(e.g.,SYTOX,EtBr,GelRed)can stain DNA but may alter its structure and mechanical properties,and cause photocleavage.Recently,a novel fluorescent DNA-binding protein(FP-DBP)was introduced,which can stain DNA without sequence preference and without inducing photocleavage.In this study,using a custom-built magnetic tweezers system,we performed DNA stretching,twisting and unzipping experiments to compare the mechanical properties of DNA with and without two kinds of intercalating dyes(SYTOX Orange and GelRed)and mCherry FP-DBP.Our results show that mCherry FP-DBP does not affect DNA structure or mechanics,unlike SYTOX Orange and GelRed,making FP-DBP a promising tool for DNA visualization in single-molecule experiments. 展开更多
关键词 fluorescent dna-binding protein SINGLE-MOLECULE magnetic tweezers DNA mechanical properties intercalating dye
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