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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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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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Lysophosphatidic acid signaling:Transmembrane modulators in the central nervous system
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作者 Alexandra Polyzou Alexandros Κ.Tsiouris +2 位作者 Charalampos Labrakakis Britta J.Eickholt George Leondaritis 《Neural Regeneration Research》 2026年第3期1104-1105,共2页
Lysophosphatidic acid(LPA)is a pleiotropic lipid agonist essential for functions of the central nervous system(CNS).It is abundant in the developing and adult brain while its concentration in biological fluids,includi... Lysophosphatidic acid(LPA)is a pleiotropic lipid agonist essential for functions of the central nervous system(CNS).It is abundant in the developing and adult brain while its concentration in biological fluids,including cerebrospinal fluid,varies significantly(Figure 1Α;Yung et al.,2014).LPA actually corresponds to a variety of lipid species that include different stereoisomers with either saturated or unsaturated fatty acids bearing likely differentiated biological activities(Figure 1Α;Yung et al.,2014;Hernández-Araiza et al.,2018). 展开更多
关键词 transmembrane modulators cerebrospinal fluidvaries variety lipid species lysophosphatidic acid biological fluidsincluding lysophosphatidic acid lpa saturated unsaturated fatty acids pleiotropic lipid agonist
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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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Saturated Alcohols Electrocatalytic Oxidations on Ni-Co Bimetal Oxide Featuring Balanced B-and L-Acidic Active Sites
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作者 Junqing Ma Wenshu Luo +9 位作者 Xunlu Wang Xu Yu Jiacheng Jayden Wang Huashuai Hu Hanxiao Du Jianrong Zeng Wei Chen Minghui Yang Jiacheng Wang Xiangzhi Cui 《Nano-Micro Letters》 2026年第2期105-123,共19页
Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electro... Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electrocatalytic oxidations of saturated alcohols(C_(1)-C_(6))to selectively form formate using Ni Co hydroxide(Ni Co-OH)derived Ni Co_(2)O_(4)solid-acid electrocatalysts with balanced Lewis acid(LASs)and Brønsted acid sites(BASs).Thermal treatment transforms BASs-rich(89.6%)Ni Co-OH into Ni Co_(2)O_(4)with nearly equal distribution of LASs(53.1%)and BASs(46.9%)which synergistically promote adsorption and activation of OH-and alcohol molecules for enhanced oxidation activity.In contrast,BASs-enriched Ni Co-OH facilitates formation of higher valence metal sites,beneficial for water oxidation.The combined experimental studies and theoretical calculation imply the oxidation ability of C1-C6alcohols increases as increased number of hydroxyl groups and decreased HOMO-LUMO gaps:methanol(C_(1))<ethylene glycol(C_(2))<glycerol(C3)<meso-erythritol(C4)<xylitol(C5)<sorbitol(C6),while the formate selectivity shows the opposite trend from 100 to 80%.This study unveils synergistic roles of LASs and BASs,as well as hydroxyl group effect in electro-upgrading of alcohols using solid-acid electrocatalysts. 展开更多
关键词 Solid-acid electrocatalyst Alcohol oxidation reaction Bronsted acid sites Lewis acid sites C_(1)-C_(6)saturated alcohols
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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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Structure insight into FtsZ function maintaining under acid stress of Streptococcus mutans
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作者 Yuxing Chen Yongliang Li +9 位作者 Jiahao Niu Liuchang Yang Yaqi Chi Xue Cai Fengjiao Xin Jie Zhang Xianyang Fang Yiqin Gao Manas Mondal Xiaoyan Wang 《International Journal of Oral Science》 2026年第1期90-102,共13页
Understanding the acid resistance mechanism of S.mutans is crucial for preventing dental caries.FtsZ is the core protein for cell division in bacteria that can polymerize into Z-rings and drive cytokinesis.Our previou... Understanding the acid resistance mechanism of S.mutans is crucial for preventing dental caries.FtsZ is the core protein for cell division in bacteria that can polymerize into Z-rings and drive cytokinesis.Our previous study revealed that the FtsZ in S.mutans(SmFtsZ) has higher self-assembly and GTPase activity under acidic stress,which may be responsible for acid resistance and ca riogenesis of S.mutans.However,the functional structure mechanism of SmFtsZ under low pH conditions is still unclear.Here,we further reported the crystal structure of S.mutans FtsZ,revealing a unique lateral interface.Through protein polymerization and GTPase activity assay,we experimentally demonstrated that the mutation of Arg68 on this lateral interface significantly reduced the functional activity of FtsZ in an acidic environment.The phenotype assay and rat caries model further showed that the mutation of Arg68 effectively inhibited the acid resistance of S.mutans and the occurrence and progress of dental caries in vivo.By employing a molecular dynamics simulation analysis,we conclude that the mutation of Arg68 disrupts the conformation change necessary for SmFtsZ polymerization under acidic conditions.Our study proposes a novel mechanism to maintain FtsZ function in bacteria and could be a potential target for antimicrobial drugs to inhibit the growth of S.mutans in acidic environments. 展开更多
关键词 ca riogenesis FTSZ acid resistance dental cariesftsz acidic stress cell division functional structure mechanism low ph conditions
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Tetrahedral framework nucleic acids in the prevention and treatment of skin and mucosal diseases:Advances and prospects
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作者 Yuge Zhang Siqi Xu +4 位作者 Chenpeng Chen Haiyu Xian Qitao Wen Yunfeng Lin Tao Wang 《Chinese Chemical Letters》 2026年第2期135-144,共10页
The application of DNA hybridization technology,grounded in Watson-Crick base pairing,has facilitated the rational design of framework nucleic acids(FNAs)featuring adaptable shapes and dimensions.These nanostructures ... The application of DNA hybridization technology,grounded in Watson-Crick base pairing,has facilitated the rational design of framework nucleic acids(FNAs)featuring adaptable shapes and dimensions.These nanostructures exhibit remarkable stability and reproducibility,making them promising candidates for biomedical applications.Among various FNAs,tetrahedral FNAs(tFNAs),first introduced by Turberfield,are nanoscale assemblies of oligonucleotides that possess unique physical,chemical,and biological properties.Previous studies have demonstrated that tFNAs exhibit excellent cellular uptake,enhanced tissue permeability,and strong capabilities to promote cell migration,proliferation,and differentiation.Moreover,the intrinsic ability of tFNAs to efficiently penetrate cell membranes allows tFNAs to serve as versatile carriers for small-molecule drugs or functional oligonucleotides,thereby exerting significant anti-inflammatory,antioxidant,antibacterial,and immunomodulatory effects.These features highlight the therapeutic potential of tFNA-based complexes in skin,mucosal,and barrier tissue repair and regeneration.This review provides a comprehensive analysis of recent advances in the application of tFNAs for the prevention and treatment of skin,mucosal,and barrier tissue diseases,with a focus on their mechanisms of action and future prospects in regenerative medicine and targeted therapies. 展开更多
关键词 Tetrahedral framework nucleic acids DNA nanomaterials Nucleic acid drugs Skin repair and regeneration Mucosal lesions
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Proteomic Analysis Revealing Protein Expression in Rice Grain Containing Differential Protein and Amino Acid Contents
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作者 Krishnendu CHATTOPADHYAY Arabinda MAHANTY +6 位作者 Nutan MOHARANA Shuvendu Shekhar MOHAPATRA Torit Baran BAGCHI Koushik CHAKRABORTY Joydeep BANERJEE Bimal Prasanna MOHANTY Trilochan MOHAPATRA 《Rice science》 2026年第1期9-14,I0012-I0027,共22页
CR Dhan 310(CRD310),a biofortified rice variety,contains a significantly higher level of grain protein compared with its recurrent parent Naveen(NV),as well as most adapted high-yielding rice varieties in India.Althou... CR Dhan 310(CRD310),a biofortified rice variety,contains a significantly higher level of grain protein compared with its recurrent parent Naveen(NV),as well as most adapted high-yielding rice varieties in India.Although a limited investigation depicted that CRD310 contained higher levels of glutelin and some essential amino acids,detailed biochemical,molecular,and cellular mechanisms remain to be studied.As one of the means to identify the proteins and understand the underlying mechanism of higher proteins accumulation in grains of CRD310,the comparative proteomics was undertaken on grains of CRD310 and NV at the yellow ripening stage. 展开更多
关键词 grain protein rice grain comparative proteomics essential amino acids identify proteins protein accumulation biochemical mechanisms amino acidsdetailed
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Amino Acid Transporter OsAAP18 Modulates Nitrogen Allocation to Boost Yield and Grain Quality in Rice
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作者 HE Chongchong YANG Xiaochuan +6 位作者 ZHANG Jie WU Wenhao WANG Chuanbo CHEN Wenbo WU Bowen HUANG Weiting FANG Zhongming 《Rice science》 2026年第2期151-154,I0028-I0040,共17页
Synergistically improving the yield and grain quality of rice remains a major breeding challenge.Amino acid transporters play key roles in regulating plant growth and development,but their mechanisms in synergisticall... Synergistically improving the yield and grain quality of rice remains a major breeding challenge.Amino acid transporters play key roles in regulating plant growth and development,but their mechanisms in synergistically regulating yield and quality remain unclear.Here,we report that the plasma membrane-localized transporter OsAAP18,which is more highly expressed in indica than japonica rice,positively correlates with tiller number and yield but negatively with grain width.OsAAP18 transports eight amino acids,including asparagine(Asn),proline(Pro),leucine(Leu),and valine(Val).Its overexpression increases yield through enhanced tillering and grain number per panicle while also improving rice processing and cooking quality.Transcriptome analysis showed that OsAAP18 coordinates grain development and quality formation by regulating the expression of key genes involved in starch and sucrose metabolism,nitrogen metabolism,and plant hormone signaling pathways.These findings establish OsAAP18 as a dual-function regulator that synergistically enhances yield and quality,offering a promising target for rice breeding. 展开更多
关键词 plasma membrane localized transporter acid transporters nitrogen allocation transports eight amino acidsi OSAAP YIELD grain quality rice breeding
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Bile acid therapy for primary biliary cholangitis:Pathogenetic validation 被引量:1
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作者 Vasiliy I Reshetnyak Igor V Maev 《World Journal of Experimental Medicine》 2025年第1期53-64,共12页
Knowledge of the etiological and pathogenetic mechanisms of the development of any disease is essential for its treatment.Because the cause of primary biliary cholangitis(PBC),a chronic,slowly progressive cholestatic ... Knowledge of the etiological and pathogenetic mechanisms of the development of any disease is essential for its treatment.Because the cause of primary biliary cholangitis(PBC),a chronic,slowly progressive cholestatic liver disease,is still unknown,treatment remains symptomatic.Knowledge of the physicochemical properties of various bile acids and the adaptive responses of cholangiocytes and hepatocytes to them has provided an important basis for the development of relatively effective drugs based on hydrophilic bile acids that can potentially slow the progression of the disease.Advances in the use of hydrophilic bile acids for the treatment of PBC are also associated with the discovery of pathogenetic mechanisms of the development of cholangiocyte damage and the appearance of the first signs of this disease.For 35 years,ursodeoxycholic acid(UDCA)has been the unique drug of choice for the treatment of patients with PBC.In recent years,the list of hydrophilic bile acids used to treat cholestatic liver diseases,including PBC,has expanded.In addition to UDCA,the use of obeticholic acid,tauroursodeoxycholic acid and norursodeoxycholic acid as drugs is discussed.The pathogenetic rationale for treatment of PBC with various bile acid drugs is discussed in this review.Emphasis is made on the mechanisms explaining the beneficial therapeutic effects and potential of each of the bile acid as a drug,based on the understanding of the pathogenesis of the initial stages of PBC. 展开更多
关键词 Primary biliary cholangitis Treatment of primary biliary cholangitis with bile acids Ursodeoxycholic acid Obeticholic acid Tauroursodeoxycholic acid Norursodeoxycholic acid
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Short-chain fatty acids mediate enteric and central nervous system homeostasis in Parkinson’s disease:Innovative therapies and their translation 被引量:1
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作者 Shimin Pang Zhili Ren +1 位作者 Hui Ding Piu Chan 《Neural Regeneration Research》 2026年第3期938-956,共19页
Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’... Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’s disease.In this review,we summarize the changes in short-chain fatty acid levels and the abundance of short-chain fatty acid-producing bacteria in various samples from patients with Parkinson’s disease,highlighting the critical role of gut homeostasis imbalance in the pathogenesis and progression of the disease.Focusing on the nervous system,we discuss the molecular mechanisms by which short-chain fatty acids influence the homeostasis of both the enteric nervous system and the central nervous system.We identify key processes,including the activation of G protein-coupled receptors and the inhibition of histone deacetylases by short-chain fatty acids.Importantly,structural or functional disruptions in the enteric nervous system mediated by these fatty acids may lead to abnormalα-synuclein expression and gastrointestinal dysmotility,which could serve as an initiating event in Parkinson’s disease.Furthermore,we propose that short-chain fatty acids help establish communication between the enteric nervous system and the central nervous system via the vagal nerve,immune circulation,and endocrine signaling.This communication may shed light on their potential role in the transmission ofα-synuclein from the gut to the brain.Finally,we elucidate novel treatment strategies for Parkinson’s disease that target short-chain fatty acids and examine the challenges associated with translating short-chain fatty acid-based therapies into clinical practice.In conclusion,this review emphasizes the pivotal role of short-chain fatty acids in regulating gut-brain axis integrity and their significance in the pathogenesis of Parkinson’s disease from the perspective of the nervous system.Moreover,it highlights the potential value of short-chain fatty acids in early intervention for Parkinson’s disease.Future research into the molecular mechanisms of short-chain fatty acids and their synergistic interactions with other gut metabolites is likely to advance the clinical translation of innovative short-chain fatty acid-based therapies for Parkinson’s disease. 展开更多
关键词 ALPHA-SYNUCLEIN blood-brain barrier blood circulation central nervous system ENDOCRINE enteric nervous system glial cell gut-brain axis gut microbiota intestinal barrier neuron Parkinson’s disease short chain fatty acids vagus nerve
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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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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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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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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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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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Synthesis,structure,and properties of hydrated tricyclohexyltin theophylline-7-acetic acid complex
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作者 HE Lifang LUO Yaoze +3 位作者 SHI Qiying TANG Jianxin ZHANG Fuxing ZHU Xiaoming 《无机化学学报》 北大核心 2026年第3期632-640,共9页
The hydrated tricyclohexyltin theophylline-7-acetic acid(tpH)complex[Sn(C_(6)H_(11))_(3)(tp)(H_(2)O)]was synthesized via an ethanol solvothermal method using tricyclohexyltin hydroxide and tpH in a 1∶1 molar ratio.Th... The hydrated tricyclohexyltin theophylline-7-acetic acid(tpH)complex[Sn(C_(6)H_(11))_(3)(tp)(H_(2)O)]was synthesized via an ethanol solvothermal method using tricyclohexyltin hydroxide and tpH in a 1∶1 molar ratio.The complex was characterized by IR,^(1)H(^(13)C)NMR,elemental analysis,and powder X-ray diffraction,and the crystal structure was determined by single-crystal X-ray diffraction.The crystal belongs to the orthorhombic system with space group Iba2,and the central tin atom is in a five-coordinated trigonal bipyramidal configuration.Quantum chemistry ab initio calculations were performed to investigate the stability,molecular orbital energy,and frontier molecular orbital characteristics of the complex.Additionally,its thermal stability,electrochemical properties,and in vitro anticancer activity were evaluated.CCDC:2380308. 展开更多
关键词 hydrated tricyclohexyltin theophylline-7-acetic acid complex SYNTHESIS crystal structure in vitro antitumor activity
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Dioscorea bulbifera L.induces liver injury in mice partly through bile acids metabolic disorders and gut microbiota dysbiosis mediated by the YY1-FXR/Nrf2 signaling pathway
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作者 Bo-Shen Zhao Yun-Dong Xie +8 位作者 Xin Wang Yu-Han Zhang Hong-Zhe Zhu Lei-Lei Shi Hui-Zi Shangguan Ling Ding Shu-Hong Zhu Cui-Cui Ren Ji-Ping Liu 《Traditional Medicine Research》 2026年第8期15-27,共13页
Background:This study aimed to comprehensively elucidate the hepatotoxic effects of Dioscorea bulbifera L.(DBL)in mice and to explore the underlying molecular mechanisms.Methods:Mice were administered different doses ... Background:This study aimed to comprehensively elucidate the hepatotoxic effects of Dioscorea bulbifera L.(DBL)in mice and to explore the underlying molecular mechanisms.Methods:Mice were administered different doses of DBL via intragastric gavage for 21 days.Organ indices of multiple organs were then measured,and histopathological changes were systematically evaluated.Particular attention was paid to biochemical markers and hepatic histopathological alterations associated with liver injury.Subsequently,the composition of the gut microbiota in colonic contents was analyzed using 16S rDNA sequencing,and the levels of short-chain fatty acids(SCFAs)were determined by gas chromatography(GC).Furthermore,protein expression levels of YinYang 1(YY1),Farnesoid X Receptor(FXR),Nuclear factor erythroid 2-related factor 2(Nrf2),and bile acids(BAs)-related proteins in the liver were assessed by Western blot analysis.Results:Our findings revealed that DBL induced varying degrees of multi-organ toxicity in mice,with the most pronounced hepatotoxicity observed.Liver injury was induced in a dose-dependent manner,accompanied by increased hepatic inflammation and oxidative stress,as well as enhanced hepatocyte apoptosis.Furthermore,DBL may modulate the YY1-FXR/Nrf2 signaling pathway,leading to upregulation of BAs-related proteins such as cholesterol 7α-hydroxylase(CYP7A1),while downregulating other BAs-related proteins,including sodium taurocholate cotransporting polypeptide(NTCP),bile salt export pump(BSEP),multidrug resistance protein 2(MRP2),and P-glycoprotein(P-gp).These changes promoted excessive BAs synthesis and impaired the excretion and reabsorption of BAs,ultimately disturbing BAs homeostasis.Additionally,DBL induces gut microbiota dysbiosis and reduces SCFAs production,leading to intestinal damage and disruption of intestinal barrier integrity.Conclusion:DBL-induced hepatotoxicity may be associated with altered expression of the YY1-FXR/Nrf2 signaling pathway and BAs–related proteins,accompanied by increased hepatic BAs accumulation and gut microbiota dysbiosis. 展开更多
关键词 DIOSCOREA bulbifera L. liver injury BILE acidS metabolism gut microbiota short-chain fatty acidS
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