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Natural compound rosmarinic acid displays anti-tumor activity in colorectal cancer cells by suppressing nuclear factor-kappa B signaling 被引量:1
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作者 Wen-Yue Liu Han Wang +5 位作者 Xin Xu Xuan Wang Kun-Kun Han Wen-Dao You Yili Yang Tao Zhang 《World Journal of Clinical Oncology》 2025年第5期171-180,共10页
BACKGROUND Rosmarinic acid(RA)is a natural polyphenol carboxylic acid known for its role in chemoprevention.Given its widespread use as a food additive,we are interested in whether RA affects the development of colore... BACKGROUND Rosmarinic acid(RA)is a natural polyphenol carboxylic acid known for its role in chemoprevention.Given its widespread use as a food additive,we are interested in whether RA affects the development of colorectal cancer(CRC).AIM To examine the anti-tumor effects of RA on various CRC cell lines,and to further investigate the possible mechanisms.METHODS Cell Counting Kit-8 assay and optical microscopy imaging were used to evaluate the viability of CRC cell lines.Western blot,quantitative real-time polymerase chain reaction,and flow cytometry analyses were performed to assess cell viability and activation of nuclear factor-kappa B(NF-κB)signaling.Molecular modeling was used to assess the interaction between RA and inhibitory kappa B kinase beta.Luciferase assay was used to examine the activity of NF-κB-driven transcription.The combinations of RA with 5-fluorouracil or oxaliplatin were utilized to evaluate the potential synergistic action of RA with the chemotherapeutics.RESULTS RA exerted potent cytotoxic actions on all six CRC cell lines examined.RA was docked nicely into the binding pocket of inhibitory kappa B kinase beta by molecular modeling.The activity of NF-κB-driven luciferase and the phosphorylation of NF-κB p65 were decreased after exposure to the compound.Lipopolysaccharide-induced NF-κB activation was effectively inhibited by RA,too.Further,RA downregulated the expression of cell proliferationrelated cyclin D1 and MYC,which are target genes of NF-κB.Of note,the cytotoxic actions of 5-fluorouracil and oxaliplatin were markedly enhanced by RA in those CRC cells.CONCLUSION Our results indicate that RA inhibits NF-κB signaling and induces apoptosis in CRC cells.It enhances the cytotoxic actions of chemotherapeutics and might help to improve the chemotherapy of CRC. 展开更多
关键词 Rosmarinic acid Colorectal cancer Cell death Nuclear factor-kappa B signaling CHEMOTHERAPY
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N-Heterocyclic Carbene Catalyzed Esterification of Dicarbaldehydes with Arylboronic Acid for Axially Chiral Phosphorus Compounds
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作者 Huang Xuehui Lin Yanru +6 位作者 Li Zhaodi Zhang Yue Wang Xin Yuanyuan Gao Gong Xiaojie Li Fei Liu Lantao 《有机化学》 北大核心 2025年第10期3847-3855,共9页
Atropisomeric phosphines are crucial for asymmetric catalysis but remain synthetically challenging.Herein,an N-heterocyclic carbene(NHC)catalyzed esterification reaction of dialdehydes with arylboronic acids was devel... Atropisomeric phosphines are crucial for asymmetric catalysis but remain synthetically challenging.Herein,an N-heterocyclic carbene(NHC)catalyzed esterification reaction of dialdehydes with arylboronic acids was developed,successfully constructing the framework of axially chiral phosphorus compounds.Mechanistic studies have revealed that the reaction initially undergoes a desymmetrization process,followed by a kinetic resolution pathway,affording a series of axially chiral phosphorus compounds with high enantioselectivity(up to 92%ee). 展开更多
关键词 axially chiral phosphorus compounds N-heterocyclic carbene ESTERIFICATION DESYMMETRIZATION
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Insight into nitrogen-doped biochar prepared from Chinese medicine compound residue for peracetic acid activation in sulfamethoxazole degradation:Electron transfer mechanism
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作者 Wenrui Jia Chenghuan Qiao +7 位作者 Dongfang Zhao Juanshan Du Yaohua Wu Yongqi Liang Qinglian Wu Xiaochi Feng Huazhe Wang Wanqian Guo 《Chinese Chemical Letters》 2025年第11期241-246,共6页
The advanced oxidation system based on peracetic acid(PAA)has been proved to be a green and safe oxidation decontamination technology.Among them,the key challenge and complexity in current research lies in the directi... The advanced oxidation system based on peracetic acid(PAA)has been proved to be a green and safe oxidation decontamination technology.Among them,the key challenge and complexity in current research lies in the directional induction of PAA and its utilization for selective removal of refractory pollutants.This study prepared nitrogen-doped biochar(NBC)using compound pharmaceutical residues commonly found in traditional Chinese medicine as a precursor.A system based on NBC-activated PAA was constructed for sulfamethoxazole(SMX)degradation.The introduction of nitrogen significantly enhanced the degree of graphitization in NBC.The degradation system achieved 87.89%SMX degradation efficiency within 60 min.Furthermore,the formation of the intricate NBC-PAA*complex detected by in-situ Raman was of paramount importance as it facilitates enhanced electron transfer processes within the complex,thereby promoting PAA decomposition through electron loss.The formation of a new complex between SMX and NBC-PAA*facilitated the completion of electron transfer process within the complex.In summary,this study explored a novel approach for treating and disposing of solid waste from Chinese medicine residue by successfully inducing non-free radical degradation pathway using PAA system.It offers fresh insights and ideas in the fields of water treatment and solid waste management. 展开更多
关键词 Chinese medicine compound residue BIOCHAR Nitrogen doping Peracetic acid Electron transfer mechanism
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Effect of Baobab (Adansonia digitata L.) Seeds Washing and Origin on Their Fatty Acids and Phenolic Compounds Oils Content
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作者 Alioune Sow Edouard Mbarick Ndiaye +9 位作者 Oumar Ibn Khatab Cissé Pape Guédel Faye Alé Kane Delphine Margout-Jantac Bou Ndiaye Samba Baldé Khadim Niane Nicolas Ayessou Patrick Poucheret Mady Cissé 《American Journal of Analytical Chemistry》 2025年第1期1-14,共14页
The aim of the present study was to evaluate the effects of baobab seed washing and origin on the chemical composition of the oil extracted by pressing. Six (6) oil samples were obtained from seeds of three (3) geogra... The aim of the present study was to evaluate the effects of baobab seed washing and origin on the chemical composition of the oil extracted by pressing. Six (6) oil samples were obtained from seeds of three (3) geographical origins. The identification and quantification of fatty acids and the polyphenolic profile were carried out by GC-MS and HPLC-UV, respectively. Analysis of fatty acid methyl esters allowed the identification and quantification of 18 fatty acids. Oils from unwashed seeds were richer in palmitic (C16:0), stearic (C18:0), oleic (C18:1) and arachidic (C20:0) acids. In addition, HPLC-UV analysis at 279 nm shows that oils from unwashed seeds are richer in tyrosol, hydroxytyrosol and caffeic acid. With regard to the polyphenolic profile, gallic acid and quercetin were not detected in these baobab oils. Principal component analysis of fatty acid and phenolic compound content showed that oils from unwashed seeds would best preserve their chemical and associated potential bioactive characteristics. 展开更多
关键词 Adansonia digitata L. SEEDS Extraction Pressure Oil Fatty acids TYROSOL Hydroxytyrosol
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Intervention effect and mechanism of Compound Herba Gueldenstaedtiae in a mouse model of breast hyperplasia
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作者 Wu Yilin Tian Hongying +8 位作者 Sun Jiale Jiao Jiajia Zhao Zihan Shao Jinhuan Zhao Kaiyue Zhou Min Li Qian Li Zexin Yue Changwu 《中国组织工程研究》 北大核心 2026年第17期4377-4389,共13页
BACKGROUND:Breast hyperplasia is a common benign breast disease mainly caused by endocrine disorders,manifested as abnormal hyperplasia of breast tissue.In recent years,traditional Chinese medicine compounds and probi... BACKGROUND:Breast hyperplasia is a common benign breast disease mainly caused by endocrine disorders,manifested as abnormal hyperplasia of breast tissue.In recent years,traditional Chinese medicine compounds and probiotics have shown good potential in regulating the endocrine system and improving the intestinal microecology,providing new ideas for the treatment of breast hyperplasia.OBJECTIVE:To explore the effects and mechanisms of traditional Chinese medicine compounds and fermented probiotic compounds on breast hyperplasia in mice,providing new theoretical and experimental bases for the clinical treatment and prevention of breast hyperplasia.METHODS:(1)Network pharmacology tools were used to predict the anti-breast-hyperplasia activity of Herba Gueldenstaedtiae(Euphorbia humifusa),as well as its potential targets and signaling pathways.The databases included:TCMSP,OMIM,GeneCards database,UniProt website,Venny2.1.0 website,Metascape,HERB website,and STRING database,all of which are open-access databases.Network pharmacology can predict and screen key information such as the targets corresponding to the active ingredients of traditional Chinese medicine,disease targets,and action pathways through network analysis and computer-system analysis.Therefore,it has been increasingly widely used in the research of traditional Chinese medicine.(2)A breast hyperplasia model was induced in mice by injecting estrogen and progesterone.Mice in the normal blank group were injected intraperitoneally with normal saline every day.Mice in the model group and drugadministration groups were injected intraperitoneally with estradiol benzoate injection at a concentration of 0.5 mg/kg every day for 25 days.From the 26th day,the injection of estradiol benzoate injection was stopped.Mice in the normal blank group were injected intramuscularly with normal saline every day,and mice in the model group and drug-administration groups were injected intramuscularly with progesterone injection at a concentration of 5 mg/kg for 5 days.After the model was established,each group was given drugs respectively.The normal blank group and the model group were gavaged with 0.2 mL/d of normal saline;the positive blank group(Xiaozheng Pill group)was gavaged with an aqueous solution of Xiaozheng Pill at 0.9 mg/g;the low-,medium-and high-dose groups of Compound Herba Gueldenstaedtiae were gavaged with an aqueous solution of the compound medicine at 0.75,1.5,and 3.0 mg/(g·d)respectively;the low-,medium-and high-dose groups of traditional Chinese medicine-bacteria fermentation were gavaged with an aqueous solution of the compound medicine at 0.75,1.5,and 3.0 mg/(g·d)respectively.The administration was continuous for 30 days.RESULTS AND CONCLUSION:(1)The results of network pharmacology research showed that the Compound Herba Gueldenstaedtiae(Euphorbia humifusa)contained 46 active ingredients,which were related to 1213 potential targets.After comparison with 588 known breast-hyperplasia targets,it was speculated that 50 of these targets might be related to the direct effect of the compound on breast hyperplasia.(2)After drug intervention,there was no significant change in the high-dose group of Compound Herba Gueldenstaedtiae compared with the normal blank group.The liver indicators of the other intervention groups all significantly decreased(P<0.05).(3)In terms of kidney and uterine indicators,the medium-dose group of Compound Herba Gueldenstaedtiae decreased significantly compared with the normal blank group(P<0.05).In terms of the uterine index,the model group increased significantly compared with the normal blank group(P<0.01).(4)After 1-month drug treatment,the number of lobules and acini in the breast tissue of the Xiaozheng Pill group,the low,medium,and high-dose group of Compound Herba Gueldenstaedtiae,the low,medium,and highdose groups of traditional Chinese medicine-bacteria fermentation decreased,and the duct openings narrowed.With the increase of drug dose,diffuse hyperplasia of breast tissue was significantly improved.(5)The ELISA results showed that compared with the model group,the estrogen level was lower in the medium-dose group of traditional Chinese medicine-bacteria fermentation after the intervention(P<0.05).In addition,the follicle-stimulating hormone level in the low-dose group of Compound Herba Gueldenstaedtiae was lower than that of the model group(P<0.05).(6)The intervention in the mouse model led to changes in the abundance of short chain fatty acids and intestinal flora in all groups.To conclude,the Compound Herba Gueldenstaedtiae and its probiotic fermentation products significantly improved mammary gland hyperplasia in mice by regulating hormone levels,improving the structure of the gut microbiota,and increasing the content of shortchain fatty acids,providing new ideas and potential sources of drugs for the treatment of breast hyperplasia. 展开更多
关键词 Herba Gueldenstaedtiae traditional Chinese medicine compound mice with breast hyperplasia microbial fermentation gut microbiota network pharmacology short-chain fatty acids hormone levels inflammatory response endocrine disorders
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Facile modification using organic acid molecules to neutralize residual alkaline compounds for stabilizing LiNi_(0.9)5Co_(0.04)Mn_(0.01)O_(2) cathode material
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作者 Chao Zhao Xiangshao Yin +7 位作者 Yuanyuan Huang Xinyu Zhang Weihong Jiang Zhuo Zhou Wenhui Tu Xianshu Wang Ding Wang Jianguo Duan 《Energy Materials and Devices》 2025年第1期84-94,83,共12页
The presence of residual alkaline compounds in the ultrahigh-nickel layered oxide cathodes(LiNi_(x)Co_(y)Mn_(1−x−y)O_(2),x≥_(0.9))aggravates structural degradation,increases surface reactivity,and promotes slurry gel... The presence of residual alkaline compounds in the ultrahigh-nickel layered oxide cathodes(LiNi_(x)Co_(y)Mn_(1−x−y)O_(2),x≥_(0.9))aggravates structural degradation,increases surface reactivity,and promotes slurry gelation,leading to the capacity decay of batteries with these cathodes and complicating their manufacturing.Traditional approaches for addressing this issue,including direct removal,coverage,and utilization,are complex and require surface regeneration.Herein,we propose neutralizing residual alkaline compounds with 3-thiopheneboronic acid(3-TBA)to improve the performance of LiNi_(0.9)5Co_(0.04)Mn_(0.01)O_(2)(NCM)cathode material,a facile strategy that does not require any post-treatment.The suggested reaction yields a uniform and thin organic-modified layer on the surface of the NCM cathode,improving its chemical stability toward the electrolyte,as demonstrated by multiple characterization methods.The modified NCM cathode exhibited impressive cyclic and rate performances,achieving a capacity retention of 83.34%after 200 cycles at 1.0 C and a specific capacity of 162.00 mAh·g^(−1) at 10.0 C.Most importantly,the proposed approach can efficiently suppress unfavorable phase transitions,severe electrolyte degradation,and CO_(2) gas evolution,improving the application potential of ultrahigh-nickel layered oxide cathode materials. 展开更多
关键词 lithium-ion battery ultrahigh-nickel layered oxide cathode residual alkaline compounds organic molecule NEUTRALIZATION
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Pd-catalyzed B—H bond activation and annulation of nido-carborane with terminal olefins: Facile construction of 2D-3D fused polycyclic compounds
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作者 SUN Fangxiang ZHANG Qing +6 位作者 ZHANG Yifan SUN Haoyi Akim VShmal′ko Sergey AAnufriev Igor BSivaev TU Deshuang YAN Hong 《无机化学学报》 北大核心 2026年第3期467-478,共12页
To address the longstanding challenge in traditional carborane methodology of rapidly and efficiently constructing carboranyl-based polycyclic frameworks,Pd-catalyzed one-pot reactions between pyridyl-substituted nido... To address the longstanding challenge in traditional carborane methodology of rapidly and efficiently constructing carboranyl-based polycyclic frameworks,Pd-catalyzed one-pot reactions between pyridyl-substituted nidocarboranes and alkynes directly afford two distinct types of 2D-3D fused carboranyl polycyclic compounds:3a-3f,4a-4d.The structures of this series of compounds were characterized by nuclear magnetic resonance spectroscopy,single-crystal X-ray diffraction,and high-resolution mass spectrometry,and a plausible reaction mechanism was proposed.Crystal structures reveal that the multiple rings in such 2D-3D fused carboranyl polycyclic compounds exhibit a certain degree of coplanarity.Furthermore,these compounds exhibited properties distinct from those of conventional 2D polycyclic systems.CCDC:2481988,3c,2481990,3f,2481986,4d. 展开更多
关键词 CARBORANE B—H bond activation polycyclic compounds
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Syntheses,structures,and catalytic performances of complexes with 4,4'-dihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid ligands
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作者 LING Weizhong LIN Jingyi +3 位作者 ZHU Jianglin LIANG Yuyi DAI Shanshan LI Yu 《无机化学学报》 北大核心 2026年第1期152-160,共9页
Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(... Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(4,4'-dihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid),phen(1,10-phenanthroline),bpb(1,4-bis(pyrid-4-yl)benzene),bpa(bis(4-pyridyl)amine),and copper,nickel and cadmium chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and singlecrystal X-ray diffraction analyses.Single-crystal X-ray diffraction analyses revealed that three complexes crystallize in the monoclinic P21/n,tetragonal I42d,and orthorhombic P21212 space groups.The complexes exhibit molecular dimers(1)or 2D metal-organic networks(2 and 3).The catalytic performances in the Knoevenagel reaction of these complexes were investigated.Complex 1 exhibits an effective catalytic activity and excellent reusability as a heterogeneous catalyst in the Knoevenagel reaction at room temperature.CCDC:2463800,1;2463801,2;2463802,3. 展开更多
关键词 COMPLEX dicarboxylic acid catalytic properties Knoevenagel reaction
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Adaptive Responses of Secale Cereale to Moderate Soil Drought:Role of Phytohormones,Free Amino Acids,and Phenolic Compounds
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作者 Lesya Voytenko Mykola Shcherbatiuk +4 位作者 Valentyna Vasyuk Kateryna Romanenko Lidiya Babenko Oleksandr Smirnov Iryna Kosakivska 《Phyton-International Journal of Experimental Botany》 2025年第7期2195-2214,共20页
Prolonged lack of rain and high-temperature lead to soil water deficits,inhibiting cereal crop growth in early ontogenesis and reducing grain quality and yield.Rye(Secale cereale L.)is a key grain crop,particularly in... Prolonged lack of rain and high-temperature lead to soil water deficits,inhibiting cereal crop growth in early ontogenesis and reducing grain quality and yield.Rye(Secale cereale L.)is a key grain crop,particularly in regions where wheat cultivation is challenging or unfeasible.To clarify its drought adaptation mechanisms,we analyzed the effects of moderate soil drought on growth,hormonal homeostasis,and the dynamics and distribution of free amino acids and phenolic compounds in rye at early vegetative stages and post-recovery.Drought triggered both general and organ-specific changes in endogenous phytohormones.A nonspecific response involved the accumulation of stress hormones abscisic acid(ABA)and salicylic acid(SA),alongside the suppression of growth hormones indole-3-acetic acid(IAA)and gibberellins.However,hormone dynamics and localization varied across plant organs.ABA and SA levels significantly increased in shoots of drought-stressed and recovered plants,corresponding with inhibited growth.Prolonged drought further enhanced ABA accumulation in both shoots and roots of recovered plants,while SA levels declined in roots but remained elevated in shoots.Drought also caused a substantial reduction in IAA,particularly in shoots,while gibberellins(GA_(3)+GA_(4))significantly decreased in roots.GA_(3)was predominant in most samples,except in the shoots of 2-day-old control plants.Post-recovery,IAA levels increased but remained below control values,while GA_(4)accumulation in roots led to a rise in total gibberellin levels.In contrast,shoot GA_(3)+GA_(4)levels declined,primarily due to GA_(3)reduction.The dominant free amino acids:aspartic acid,glutamic acid,glycine,alanine,and leucinedecreased significantly,underscoring their key role in stress adaptation.Increased flavonoid accumulation,especially in roots,suggests their involvement in antioxidant defense against oxidative stress.A significant increase in ABA and SA levels,along with a marked reduction in IAA and GA content in stressed rye plants occurred alongside a reduction in free amino acid content,accumulation of phenolic compounds,and an increase in flavonoid levels.These findings indicate distinct adaptation strategies in rye shoots and roots undermoderate soil drought.They provide a foundation for further research on drought resistance mechanisms in cereals and the development of strategies to enhance their adaptive potential. 展开更多
关键词 Secale cereale L. soil drought GROWTH PHYTOHORMONES amino acids PHENOLS FLAVONOIDS adaptation strategies
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The study on citric acid-modified HUSY catalyzed alkylation of phenol with cyclohexanol
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作者 HUA Canhao WU Jingfeng +2 位作者 ZHU Lingjun XU Guangwen WANG Shurong 《燃料化学学报(中英文)》 北大核心 2026年第3期58-70,共13页
Lignin-derived oxygenated aromatics,particularly phenols and aromatic ethers obtained through depolymerization,represent promising feedstocks for synthesizing high-density and high-heat-sink aviation fuels via alkylat... Lignin-derived oxygenated aromatics,particularly phenols and aromatic ethers obtained through depolymerization,represent promising feedstocks for synthesizing high-density and high-heat-sink aviation fuels via alkylation-hydrogenation processes.This study systematically evaluates the catalytic performance of various zeolites(Hβ,HZSM-5,MCM-41 and HUSY)in the alkylation reaction of phenol with cyclohexanol.Characterization results demonstrate that HUSY zeolite showed superior catalytic activity compared to other zeolites,attributable to its favorable pore architecture and well-balanced acid site distribution that synergistically facilitate molecular diffusion and catalytic transformations.To further enhance the catalytic properties,HUSY zeolite was modified with citric acid at various concentrations and compared with those treated with NaOH and oxalic acid.The results revealed that citric acid treatment preserved the crystallinity of the zeolite while modulating its acid distribution and pore structure.All modified zeolites enhanced phenol alkylation activity.Notably,the HUSY-0.5M catalyst,which exhibited the highest medium-strong acid to total acid ratio,achieved superior catalytic performance,80.4%conversion of phenol and 99.6%selectivity for alkylation products.The catalyst also exhibited high activity in the alkylation of various lignin-derived compounds,demonstrating its broad applicability.This work provides a new strategy for the valorization of lignin-derived phenols into high-value fuel precursors through alkylation. 展开更多
关键词 citric acid modification HUSY phenolic alkylation aviation fuel
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Influence of the distance between Brønsted acid sites and Mo sites in Mo/HZSM-5 on the mechanism of methane dehydroaromatization performance
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作者 WANG Ce WEI Lihong +2 位作者 ZHANG Qinghao ZHANG Hongxiang SUN Yuewen 《燃料化学学报(中英文)》 北大核心 2026年第4期68-81,共14页
Methane dehydroaromatization(MDA)presents a promising carbon-neutral pathway for benzene,toluene,and xylene(BTX)production,alternative to petroleumderived routes.Elucidating the regulatory mechanisms of Brønsted ... Methane dehydroaromatization(MDA)presents a promising carbon-neutral pathway for benzene,toluene,and xylene(BTX)production,alternative to petroleumderived routes.Elucidating the regulatory mechanisms of Brønsted acid site(BAS)strength on reaction pathways,alongside the spatial proximity effects between BAS and Mo active sites in bifunctional synergy,remains a critical scientific challenge in catalyst design.This study systematically tunes both BAS strength(via isomorphous metal substitution)and Mo-BAS spatial proximity in zeolites,integrating MDA catalytic evaluations with density functional theory(DFT)calculations to dissect their individual contributions.Strongly acidic BAS catalysts(compared to moderately acidic Fe/Ga-substituted counterparts)exhibit superior performance,evidenced by enhanced aromatic yields.Conversely,weakly acidic Bsubstituted zeolites demonstrate optimal mono-/bifunctional synergy,outperforming moderate-acid systems.DFT results reveal that acid strength dictates C−H activation mechanisms by modulating the energy barriers of rate-determining steps.While Al-zeolites deliver the highest activity,B-substituted systems display unique potential for mechanistic investigations.Spatial proximity analysis indicates that micrometer-scale Mo-BAS distances hinder effective synergy due to exceeding electron interaction and mass transfer limits,whereas nanometer-scale proximity enhances activity(via accelerated intermediate transport)and suppresses coke formation.These findings establish a theoretical framework for rationalizing zeolite catalyst optimization through BAS property engineering and spatial control of Mo-BAS cooperation,providing actionable guidelines for designing next-generation MDA catalysts. 展开更多
关键词 methane dehydroaromatization Brønsted acid catalytic mechanism ZEOLITE
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Pressure-induced high-energy-density and superhard Be-C-O compounds
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作者 Jinming Zhu Kuo Bao +3 位作者 Zhaoqing Wang Yuan Qin Hongyu Yu Tian Cui 《Matter and Radiation at Extremes》 2026年第2期95-103,共9页
Light element compounds under high pressure display intriguing properties and applications,owing to their diverse bonding patterns and crystalline structures.However,the system of ternary Be-C-O compounds under high p... Light element compounds under high pressure display intriguing properties and applications,owing to their diverse bonding patterns and crystalline structures.However,the system of ternary Be-C-O compounds under high pressure,as the lightest representative of the IIA-IVA-VIA family,remains largely unexplored.Using a machine-learning-accelerated crystal structure search and first-principles calculations,Be-C-O phase diagrams are investigated at pressures ranging from 0 to 100 GPa.Four ternary compounds are proposed to be stable at corresponding pressures:BeCO_(3),Be_(2)CO_(4),Be_(2)C_(4)O_(3),and BeC_(4)O_(2).Analyses of electronic structure and chemical bonding further reveal how the structural diversity of these compounds is induced.Remarkably,Be_(2)C_(4)O_(3) and BeC_(4)O_(2) are recoverable to ambient conditions and possess both high energy density and high hardness.The volumetric energy densities of Be_(2)C_(4)O_(3) and BeC_(4)O_(2) could approach 9.03 and 7.94 kJ/cm^(3),respectively.The Vickers hardnesses of Be_(2)C_(4)O_(3) and BeC_(4)O_(2) are found to be close to 39.58 and 51.57 GPa,respectively.These findings demonstrate the structural and functional diversity of Be-C-O compounds under high pressure,providing guidance for further exploration of the IIA-IVA-VIA compounds. 展开更多
关键词 bonding patterns ternary compounds SUPERHARD high energy density crystal structure search light element compounds be c o compounds pressure induced
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Integrated Transcriptomic and Metabolomic Analysis Reveals the Adaptive Mechanism of Penicillium digitatum under Modified Atmosphere Packaging Based on Amino Acid Metabolism
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作者 HAO Shanshan WANG Zhengli +3 位作者 XU Huihui JI Nana GUO Yanyin Abbas AQLEEM 《食品科学》 北大核心 2026年第6期129-144,共16页
This study employed integrated multi-omics approaches to elucidate,from the perspective of amino acid metabolism,the adaptive mechanism of Penicillium digitatum under modified atmosphere packaging(MAP)conditions.Compa... This study employed integrated multi-omics approaches to elucidate,from the perspective of amino acid metabolism,the adaptive mechanism of Penicillium digitatum under modified atmosphere packaging(MAP)conditions.Comparative analysis of natural air(Air),controlled atmosphere(CA),and MAP treatments revealed that MAP upregulated the expression of the hercynylcysteine S-oxide synthase(HCSOS),aldehyde dehydrogenase(ALDH),and monoamine oxidase(MAO)genes,thereby enhancing histidine-derived ergothioneine and methionine levels,and subsequently boosting glutathione-mediated redox homeostasis.Meanwhile,MAP induced the expression of the dihydroxyacid dehydratase(DHAD),saccharopine dehydrogenase(SDH),and arginosuccinate lyase(ASL)genes,redirecting valine,lysine,and arginine into the tricarboxylic acid(TCA)cycle to fuel ATP production.MAP also enhanced ASL-mediated arginine degradation and urea cycle activity,reducing arginine accumulation when compared to CA treatment.In contrast,while MAP induced upregulated expression of the pyrroline-5-carboxylate dehydrogenase(P5CDH)and D-amino acid oxidase(DAAO)genes,CA treatment promoted proline accumulation,reflecting stress-specific metabolic flexibility.Collectively,these findings demonstrate that MAP triggers transcriptional reprogramming of amino acid metabolism to coordinate oxidative defense,energy generation,and osmotic balance.By modulating these metabolic pathways and regulatory genes under MAP conditions,fungal adaptability can be disrupted.Hence,this study provides a promising strategy for suppressing green mold development,extending the postharvest shelf life,and improving the quality of fruits and vegetables. 展开更多
关键词 amino acid metabolism multi-omics Penicillium digitatum modified atmosphere packaging postharvest pathology
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Photocatalytic Radical-Mediated Synthesis of Unnaturalα-Amino Acids from Heteroaryl Aldehydes
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作者 Ren Ke Zhang Guanglu +3 位作者 Niu Yifan Wang Xiaomeng Chen Canyu Jiang Min 《有机化学》 北大核心 2026年第1期215-224,共10页
Non-naturalα-amino acids(α-AAs)are pivotal in drug and catalysis,yet their synthesis remains challenges.A photocatalytic strategy for the direct construction of N-heteroaryl-containingα-AAs from heteroaryl aldehyde... Non-naturalα-amino acids(α-AAs)are pivotal in drug and catalysis,yet their synthesis remains challenges.A photocatalytic strategy for the direct construction of N-heteroaryl-containingα-AAs from heteroaryl aldehydes via acyl radical intermediates is reported.This method exhibits exceptional functional group tolerance and enables late-stage diversification of peptides and carbonyl-group derivatization.Mechanistic studies confirm a radical-based pathway,while applications in peptide modification highlight its utility in bioorganic chemistry. 展开更多
关键词 PHOTOCATALYTIC non-natural amino acids heteroaryl aldehydes acyl radical electron paramagnetic resonance
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Efficient leaching and separation of iron,aluminum,and calcium from carbon-rich components in coal gasification fine slag using organic acids
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作者 NAN Tianhao ZHOU Anning +4 位作者 HAN Rui HAN Chunmeng CHEN Heng ZHANG Ningning LI Bingying 《燃料化学学报(中英文)》 北大核心 2026年第4期1-16,共16页
The efficient extraction and separation of valuable metal elements from coal gasification fine slag(CGFS)are crucial for the comprehensive high-value utilization of its constituents.This study focused on the carbon-ri... The efficient extraction and separation of valuable metal elements from coal gasification fine slag(CGFS)are crucial for the comprehensive high-value utilization of its constituents.This study focused on the carbon-rich components of CGFS(CGFS-H)and systematically investigates the selective leaching behavior of Fe^(3+),Al^(3+)and Ca^(2+)using three organic acid extractants,i.e.,citric acid,tartaric acid,and tetrasodium iminodisuccinate.Additionally,the stepwise leaching of iron,aluminum and calcium from CGFS-H is explored.The selective dissolution mechanisms of these metals by different organic acids are elucidated through X-ray diffraction(XRD),X-ray fluorescence(XRF),and scanning electron microscopy(SEM)analyses.The results indicate that tetrasodium iminodisuccinate exhibits the highest leaching selectivity for Fe^(3+),while tartaric acid demonstrateds a comparable affinity for both Fe^(3+)and Al^(3+).In contrast citric acid shows superior selectivity toward Ca^(2+).The leaching yield of Fe^(3+),Al^(3+)and Ca^(2+)after sequential leaching with the three organic acids were 79.8%,65.08%and 78.6%,respectively.These findings confirm that effective and selective separation of Fe^(3+),Al^(3+)and Ca^(2+)from CGFS-H can be achieved via optimized organic acid-based leaching strategies.This advancement provides a critical foundation for developing Ca/Fe/Al hydrotalcite materials using CGFS-H as a sustainable feedstock,thereby facilitating the transformation of waste residue into high-value functional materials and promoting resourceefficient utilization of coal gasification fine slag. 展开更多
关键词 coal gasification fine slag carbon-rich components organic acids LEACHING stepwise extraction
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Linoleic acid alleviates mood disorders in mice by modulating microglia differentiation and arachidonic acid metabolism
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作者 Meishan Lu Yanjun Liu +4 位作者 Mengxue He Jiachen Shi Yanan Wang Xue Li Yuanfa Liu 《Food Science and Human Wellness》 2026年第2期892-907,共16页
In previous research,we demonstrated that long-term consumption of thermally oxidized oil leads to neuroinflammation and anxiety in mice.Therefore,in this study,we employed polar lipid components from thermo-induced o... In previous research,we demonstrated that long-term consumption of thermally oxidized oil leads to neuroinflammation and anxiety in mice.Therefore,in this study,we employed polar lipid components from thermo-induced oxidized oil to induce neurodamage.Behavioral assessments revealed that both the linoleic acid and AUDA(a classical inhibitor of soluble epoxide hydrolase)groups exhibited significantly reduced anxiety-like behaviors compared to the model group(P<0.05).Immunofluorescence analysis indicated that microglial activation in the hippocampus was attenuated in both the linoleic acid and AUDA groups relative to the model group,accompanied by a reduction in the m RNA expression of pro-inflammatory cytokines(IL-1β,IL-6,NOS2,TNF-α)and an upregulation of neuroprotective factors(IL-4,IL-10,BDNF).Lipidomic profiling of hippocampal tissue revealed that the lipid composition of the linoleic acid group closely resembled that of the AUDA group,with a significant downregulation of cardiolipin(CL)compared to the control group,consistent with alterations in the membrane potential channel receptor TRPC1.Both linoleic acid and AUDA inhibited the m RNA expression of EPHX2,leading to an increase in epoxyeicosatrienoic acids(EETs)levels.Furthermore,linoleic acid upregulated the expression of cytochrome P450 enzymes(CYP2J6)and lipoxygenase(LOX2S),which further upregulated the synthesis of EETs,and increased the content of 9-HODE and 13-HODE.These findings collectively suggest that linoleic acid alleviates neuroinflammation by modulating microglial differentiation and attenuates neurodegeneration induced by thermally oxidized oil through the regulation of arachidonic acid metabolism and the linoleic acid metabolic pathway,leading to the production of neuroprotective lipid mediators.Therefore,linoleic acid may serve as a potential neuro-nutrient for the treatment of anxiety disorders.This provided a scientific basis for the development of specialized medical foods aimed at protecting neural health. 展开更多
关键词 Linoleic acid ANXIETY MICROGLIA Arachidonic acid
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Recent advances in the magnetism of layered transition-metal compoundsII.CLASSIFICATION AND MAGNETIC PROPERTIES OF LAYERED TRANSITION METAL COMPOUNDS
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作者 XU Jie ZHANG Yaling +5 位作者 LIU Xiaoxuan WANG Yuanyuan XUE Tingyuan GU Liang MAN Xiaoxiao ZHANG Huisheng 《物理学进展》 北大核心 2026年第2期51-71,共21页
Layered transition-metal compounds(LTMCs)feature stacked architectures,strong magnetic anisotropy,and tunable magnetic order,making them promising material platforms for low-power spintronic technologies and for enabl... Layered transition-metal compounds(LTMCs)feature stacked architectures,strong magnetic anisotropy,and tunable magnetic order,making them promising material platforms for low-power spintronic technologies and for enabling topological functionalities in the post-Moore era.Here we review recent progress on two-dimensional(2D)magnetism in LTMCs,emphasizing material taxonomy,intrinsic magnetic properties,and external-field controls.This review first presents a classification of LTMCs by crystal structure and chemistry—binary halides,chalcogenides,and ternary families(e.g.,MPX_(3),M_(m)X_(n)Te_(k),MnBi_(2)Te_(4))—followed by a summary of their coupling mechanisms,ordering temperatures,and dimensional effects.It then analyzes the modulation of exchange interactions,magnetic anisotropy,and topological states by electric-field gating,strain engineering,and ion intercalation,with representative experimental demonstrations.Notable advances include room-temperature ferromagnetic metals and semiconductors,observation of the quantum anomalous Hall effect(QAHE)in MnBi2Te4,and synergistic control of magnetic-topological states under multiple external stimuli.Persistent challenges involve the limited availability of intrinsic 2D magnetic semiconductors with high Curie temperatures(Tc),incomplete understanding of the microscopic couplings at interfaces and under quantum confinement,and device-level stability.We conclude by outlining opportunities that lie in the integration of multiscale characterization,first-principles theory,and cross-scale fabrication to precisely co-engineer magnetism,topology,and electronic structure,thereby advancing LTMCs toward spintronic and topological-quantum applications. 展开更多
关键词 layered transition-metal compounds two-dimensional magnetism electric-field control strain engineering ion intercalation topological magnetism quantum anomalous Hall effect
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Taurodeoxycholic,taurocholic,and glycocholic acids promote hepatic gluconeogenesis via TGR5 in dairy cows
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作者 Miaomiao Zhu Yining Zheng +7 位作者 Shiyang Lou Ruixu Zhang Dingping Feng Xinjian Lei Lei Chen Jianguo Wang Junhu Yao Lu Deng 《Journal of Animal Science and Biotechnology》 2026年第1期500-515,共16页
Background Ruminants and monogastric animals exhibit significant differences in gluconeogenic efficiency.In dairy cows,hepatic gluconeogenesis serves as the primary source of glucose.Metabolites modulate gluconeogenes... Background Ruminants and monogastric animals exhibit significant differences in gluconeogenic efficiency.In dairy cows,hepatic gluconeogenesis serves as the primary source of glucose.Metabolites modulate gluconeogenesis efficiency through allosteric regulation,redox state,and signal transduction pathways.However,the liver-enriched metabolites that regulate hepatic gluconeogenesis in dairy cows and their specific regulatory mechanisms remain incompletely characterized.Results Six Holstein dairy cows and six Duroc×(Landrace×Yorkshire)(DLY)crossbred pigs served as research subjects.Employing non-targeted and targeted metabolomics,we discovered that three bile acids—taurodeoxycholic acid(TDCA),taurocholic acid(TCA),and glycocholic acid(GCA)—were highly enriched in Holstein dairy cows'livers.In bovine hepatocytes,individual or combined stimulation of these bile acids significantly upregulated the expression of gluconeogenesis genes(FBP1,PCK1 and G6PC)and enhanced glucose production.In fasting mice with induced gluconeogenesis,TDCA,TCA,and GCA increased fasting blood glucose levels,and pyruvate tolerance tests further revealed their capacity to enhance hepatic gluconeogenesis,enabling more efficient glucose synthesis from pyruvate.Mechanistically,these bile acids activated Takeda G protein-coupled receptor 5(TGR5),elevated intracellular cAMP levels,and ultimately enhanced gluconeogenesis via the transcription factor cAMP-response element binding protein(CREB).Notably,a TGR5 inhibitor abrogated the stimulatory effects of TDCA,TCA,and GCA on hepatic gluconeogenesis in fasting mice.Conclusion TDCA,TCA,and GCA are key metabolites promoting hepatic gluconeogenesis in dairy cows,with TGR5 as the pivotal receptor and the cAMP/PKA/CREB pathway as the critical downstream mechanism. 展开更多
关键词 cAMP-response element binding protein GLUCONEOGENESIS Glycocholic acid Takeda G protein-coupled receptor 5 Taurocholic acid Taurodeoxycholic acid
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The evolution of lipid nanoparticles: Paving the way for next-generation nucleic acid medicines
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作者 Xuan Lin Hongguang Xiang +7 位作者 Jiong Wu Ruixi Liao Yuhao Li Bohui Xu Ying Xu Yan Shen Qian Li Yu Tian 《Asian Journal of Pharmaceutical Sciences》 2026年第1期75-108,共34页
Nucleic acid-based therapies have emerged as promising strategies for the regulation of gene expression and the production of therapeutic antigens or proteins for a series of diseases, including cancers, rare diseases... Nucleic acid-based therapies have emerged as promising strategies for the regulation of gene expression and the production of therapeutic antigens or proteins for a series of diseases, including cancers, rare diseases, and infectious diseases. However, their clinical application faces challenges. These include high molecular weight, limited cellular uptake,and susceptibility to enzymatic degradation by nucleases in vivo. Both viral and non-viral delivery vectors have been developed as a means of addressing these limitations, including lipid nanoparticles(LNPs), exosomes, polymers, and inorganic nanoparticles. Among these,LNPs have garnered significant attention due to their superior biocompatibility, high delivery efficiency and customizable design potential, as demonstrated by the clinical success of the FDA-approved si RNA drug Onpattro®. The critical role of nucleic acid drug carriers is discussed in this review. It also outlines the major types of carriers under development and examines the advancements and applications in LNP-based systems for nucleic acid delivery. By conducting a review of recent advancements in LNP design, delivery mechanisms, and clinical applications, this article aims to clarify the ways in which LNPs overcome delivery barriers, compare LNPs with other carriers, and identify key trends that can inform the development of next-generation LNP platforms for nucleic acid therapeutics. 展开更多
关键词 Nucleic acid therapeutics Nucleic acid drugs Delivery systems Nucleic acid delivery challenges Lipid nanoparticle carriers
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Contents of linoleic acid,α-linolenic acid and their ratio in human milk,influence factors,and effects on infant health
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作者 Jiahui Yu Lili Zheng +7 位作者 Shengyuan Ye Xingwang Ye Shuangshuang Chen Zhiyuan Yan Zhengdong Liu Yuanyuan Yan Wei Wei Xingguo Wang 《Food Science and Human Wellness》 2026年第1期28-37,共10页
Both linoleic acid(18:2 n-6,LA)andα-linolenic acid(18:3 n-3,ALA)are essential fatty acids for infants.The contents of LA and ALA,and their ratio exhibited significant changes in human milk over the past 4 decades,whi... Both linoleic acid(18:2 n-6,LA)andα-linolenic acid(18:3 n-3,ALA)are essential fatty acids for infants.The contents of LA and ALA,and their ratio exhibited significant changes in human milk over the past 4 decades,which were not well summarized.Here,we summarized these values in 9898 human breast milk samples of 6664 mothers from 50 countries in 81 studies.A literature search was conducted using PubMed,Embase,and Web of Science between January 1980 and October 2023.The 95%confidence interval of LA/ALA ratio across lactation and gestation ranged from 14.24 to 31.26.The LA content was higher in China and Turkey(>20%)whereas the ALA content was below 1%in Africa.The LA/ALA ratio in countries along the Mediterranean coast exceeded 20 or even 30.LA and ALA contents increased significantly(P<0.01)while the ratio remained stable over the last 40 years.Multivariate meta-regression results showed that regions significantly(P<0.01)determined the LA,ALA,and LA/ALA ratio.Especially,maternal diet could definitely explain the variation while the effects of gestational age,lactation period was not significant.Clinical trials demonstrated that decreasing the LA/ALA ratio increased docosahexaenoic acid(22:6 n-3,DHA)status,reduced arachidonic acid(20:4 n-6,AA)contents,exerted no effect on the visual function of infants,and reached no consensus on growth.The current review aims to provide an overview on the LA and ALA contents and their ratio in human breast milk to raise concern in infant formula. 展开更多
关键词 Human milk Linoleic acid α-Linolenic acid Essential fatty acid Infant nutrition Clinical trial Lactation period Maternal diet
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