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Stabilized carbon radical-mediated three-component functionalization of amino acid/peptide derivatives
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作者 Shaofeng Gong Zi-Wei Deng +1 位作者 Chao Wu Wei-Min He 《Chinese Chemical Letters》 2025年第5期3-4,共2页
Amino acids are the building blocks of proteins and play vital roles in both biological systems and drug development.In recent years,increasing attention has been given to the functionalization of amino acid derivativ... Amino acids are the building blocks of proteins and play vital roles in both biological systems and drug development.In recent years,increasing attention has been given to the functionalization of amino acid derivatives.Since the introduction of therapeutic insulin in the early 20th century,the conjugation of drug molecules with amino acids and peptides has been pivotal in driving advancements in drug discovery and become an integral part of modern medical practice.Currently,over a hundred peptide-drug conjugates have received global approval and are widely used to treat diseases such as diabetes,cancer,chronic pain,and multiple sclerosis.Key technologies for conjugating peptides with bioactive molecules include antibody-drug conjugates(ADCs),peptide-drug conjugates(PDCs),and proteolysis targeting chimeras(PROTACs).Significant efforts have been dedicated to developing strategies for the modification of amino acids and peptides,with particular focus on site-selective C-H alkylation/arylation reactions.These reactions are crucial for synthesizing bioactive molecules,as they enable the precise introduction of functional groups at specific positions,thereby improving the pharmacological properties of the resulting compounds. 展开更多
关键词 stabilized carbon radical mediated functionalization three component reactions therapeutic insulin drug developmentin drug discovery amino acids conjugation drug molecules biological systems
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Prediction,screening,characterization,antioxidant and antihypoxic effects of multi-component zwitterionic cocrystals of dietary flavonoids with picolinic acid
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作者 Yao Zou Difei Gong +6 位作者 Haiguang Yang Hongmei Yu Guorong He Ningbo Gong Lianhua Fang Guanhua Du Yang Lu 《Chinese Chemical Letters》 2025年第9期581-588,共8页
The objective of this study was to predict,screen,synthesize,and investigate cocrystals of poorly soluble flavonoids that are commonly found in dietary supplements with bipolar compound picolinic acid(PA).To improve t... The objective of this study was to predict,screen,synthesize,and investigate cocrystals of poorly soluble flavonoids that are commonly found in dietary supplements with bipolar compound picolinic acid(PA).To improve the efficiency and success rate of experimental screening,two virtual tools based on hydrogen bond propensity(HBP)and modified molecular electrostatic potential(MEP)maps were used.The prediction accuracy of HBP and MEP is 58.82%and 94.11%,respectively,presenting that the MEP model is very powerful in the discovery of pharmaceutical cocrystals.Among the 12 successfully obtained cocrystals,4 single crystals of PA with luteolin(LUT),genistein(GEN),taxifolin(TAX),dihydromyricetin(DHM)were obtained for the first time.Charged-assisted O-H…O and N-H…O hydrogen bonds appear as main hydrogen bonding synthons,and PA adopts a zwitterionic form after cocrystallization.GEN-PA,TAX-PA,and DHM-PA showed higher DPPH'radical-scavenging capacities;LUT-PA and DHM-PA showed higher ABTS^(+)radical-scavenging capacities;GEN-PA and DHM-PA possessed better protective effects on H9c2 cells from hypoxic injury caused by CoCl_(2)than corresponding pure flavonoids. 展开更多
关键词 COCRYSTAL Flavonoid Picolinic acid Dietary supplements ZWITTERIONIC
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Study on Optimization of Ultrasonic Extraction Process for Benzoic Acid as a Harmful Component in Paeonia Iactiflora Pall
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作者 Shangyue Chen Guiming Guo +5 位作者 Gang Chen Yanxin Zhai Jingliang Xie Xu Zhao Mingxue Cai Xuegang Zhou 《Chinese Medicine and Natural Products》 2025年第3期193-198,共6页
Objective To optimize the ultrasonic extraction process for benzoic acid as a harmful substance in Paeonia lactiflora Pall.(P.lactiflora Pall.).Methods Methanol and ethanol solutions at different concentration gradien... Objective To optimize the ultrasonic extraction process for benzoic acid as a harmful substance in Paeonia lactiflora Pall.(P.lactiflora Pall.).Methods Methanol and ethanol solutions at different concentration gradients(25,50,75%)were prepared to investigate the effects of extraction solvents on the extraction efficiency of benzoic acid.The influences of ultrasonic frequency(35,50 Hz),ultrasonic power(40,60,80,100 W),ultrasonic time(10,20,30,40,50,60 minutes),and ultrasonic temperature(20,30,40,50℃)on the extraction efficiency were examined.Orthogonal experiments were conducted to analyze the effects of temperature,time,and ultrasonic power on the extraction efficiency and to screen the optimal ultrasonic extraction process.Results Various influencing factors had certain effects on the extraction efficiency of benzoic acid from P.lactiflora Pall.Single-factor analysis revealed that 25%methanol,ultrasonic frequency of 50 Hz,ultrasonic power of 40 W,ultrasonic time of 10minutes,and ultrasonic temperature of 30℃yielded the highest extraction efficiency for benzoic acid.The order of influence of different factors on the extraction efficiency was temperature>time>power.The optimal conditions obtained from orthogonal experiments were:extraction solvent of 25%methanol,ultrasonic frequency of 50 Hz,ultrasonic time of 20 minutes,ultrasonic power of 40 W,and ultrasonic temperature of 30℃.Conclusion Under the conditions of 25%methanol as the extraction solvent,ultrasonic frequency of 50 Hz,ultrasonic time of 20 minutes,ultrasonic power of 40 W,and ultrasonic temperature of 30℃,the extraction efficiency of benzoic acid from P.lactiflora Pall.was the highest.This method offers advantages such as simple operation,small sample size requirement,and low solvent consumption,providing a reliable analytical approach for quality control and safety evaluation of P.lactiflora Pall. 展开更多
关键词 Paeonia lactiflora Pall. benzoic acid ultrasonic extraction process optimization
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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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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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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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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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Branched-Chain Amino Acid Metabolic Reprogramming and Cancer:Molecular Mechanisms,Immune Regulation,and Precision Targeting
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作者 Dongchi Cai Jialin Ji +1 位作者 Chunhui Yang Hong Cai 《Oncology Research》 2026年第1期174-201,共28页
Metabolic reprogramming involving branched-chain amino acids(BCAAs)—leucine,isoleucine,and valine—is increasingly recognized as pivotal in cancer progression,metastasis,and immune modulation.This review comprehensiv... Metabolic reprogramming involving branched-chain amino acids(BCAAs)—leucine,isoleucine,and valine—is increasingly recognized as pivotal in cancer progression,metastasis,and immune modulation.This review comprehensively explores how cancer cells rewire BCAA metabolism to enhance proliferation,survival,and therapy resistance.Tumors manipulate BCAA uptake and catabolism via high expression of transporters like L-type amino acid transporter 1(LAT1)and enzymes including branched chain amino acid transaminase 1(BCAT1),branched chain amino acid transaminase 2(BCAT2),branched-chain alpha-keto acid dehydrogenase(BCKDH),and branched chain alpha-keto acid dehydrogenase kinase(BCKDK).These alterations sustain energy production,biosynthesis,redox homeostasis,and oncogenic signaling(especially mammalian target of rapamycin complex 1[mTORC1]).Crucially,tumor-driven BCAA depletion also shapes an immunosuppressive microenvironment,impairing anti-tumor immunity by limiting essential nutrients for T cells and natural killer(NK)cells.Innovative therapeutic strategies targeting BCAA pathways—ranging from selective small-molecule inhibitors(e.g.,LAT1 and BCAT1/2)to dietary modulation—have shown promising preclinical and early clinical efficacy,highlighting their potential to exploit metabolic vulnerabilities in cancer cells while bolstering immune responses.By integrating multi-omics data and precision targeting approaches,this review underscores the translational significance of BCAA metabolic reprogramming,positioning it as a novel frontier in cancer treatment. 展开更多
关键词 Branched-chain amino acids metabolic reprogramming tumor microenvironment targeted therapy
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AGPAT3 Regulates Immune Microenvironment in Osteosarcoma via Lysophosphatidic Acid Metabolism
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作者 Shenghui Su Yu Zeng +1 位作者 Jiaxin Chen Xieping Dong 《Oncology Research》 2026年第1期598-619,共22页
Background:Recent studies have shown glycerolipid metabolism played an essential role in multiple tumors,however,its function in osteosarcoma is unclear.This study aimed to explore the role of glycerolipid metabolism ... Background:Recent studies have shown glycerolipid metabolism played an essential role in multiple tumors,however,its function in osteosarcoma is unclear.This study aimed to explore the role of glycerolipid metabolism in osteosarcoma.Methods:We conducted bioinformatics analysis using data from the Therapeutically Applicable Research to Generate Effective Treatments(TARGET)database and single-cell RNA sequencing.Least Absolute Shrinkage and Selection Operator(LASSO)regression was used to identify the Glycerolipid metabolism-related genes associated with the clinical outcome of osteosarcoma.Tumor-associated macrophages(TAMs)and their interactions with immune cells were examined through single-cell analysis and co-culture experiments.Virtual screening was employed to identify the potential lysophosphatidic acid receptor 6(LPAR6)inhibitors.Results:Glycerolipid metabolism-related genes 1-acylglycerol-3-phosphate O-acyltransferase 3(AGPAT3)and aldehyde dehydrogenase 7 family member A1(ALDH7A1)were identified as key prognostic genes in osteosarcoma,with high AGPAT3 expression correlating with improved survival.Single-cell analysis revealed that AGPAT3 expression is associated with tumor immune microenvironment,particularly with TAMs.Knockdown of AGPAT3 in osteosarcoma cells resulted in elevated lysophosphatidic acid(LPA)levels,which regulated the immune environment,inhibiting cytotoxic T cell function through TAMs’LPAR6 signaling.LPAR6 signaling in TAMs mediates immune regulation through cytokine secretion,including interleukin-6(IL-6)and interleukin-10(IL-10).Further drug virtual screening identified Dutasteride as a potential inhibitor of LPAR6.Conclusion:AGPAT3 is an important gene related to the prognosis of osteosarcoma.Its ability to modulate LPA signaling and TAM activity offers promising therapeutic opportunities for improving osteosarcoma treatment,particularly in immunotherapy contexts. 展开更多
关键词 1-acylglycerol-3-phosphate O-acyltransferase 3 OSTEOSARCOMA SINGLE-CELL tumor-associated macrophages lysophosphatidic acid
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Oleanolic acid inhibits mitochondrial fission by improving mitochondrial dysfunction and reducing atherosclerosis via regulating AMPK/Drp1 pathway:An in vivo and in vitro study
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作者 Jin-Zhou Xie Wei-Jia Cui +1 位作者 Wei-Tian Zhong Liang Ning 《Asian Pacific Journal of Tropical Biomedicine》 2026年第1期24-39,共16页
Objective:To investigate effect of oleanolic acid(OA)on atherosclerosis and its related mechanisms.Methods:Human umbilical vein endothelial cells(HUVECs)were injured by oxidized low-density lipoprotein for 24 h and tr... Objective:To investigate effect of oleanolic acid(OA)on atherosclerosis and its related mechanisms.Methods:Human umbilical vein endothelial cells(HUVECs)were injured by oxidized low-density lipoprotein for 24 h and treated with OA,and the levels of cell proliferation,migration,adhesion,and apoptosis were evaluated by BrdU staining,scratch healing assay,monocyte-endothelial cell adhesion assay and flow cytometry.The mice were fed with a high-fat diet to induce an atherosclerosis model,and treated with OA by gastric gavage.The mice were divided into the control group,the model group,and the OA administration group.The blood lipid and plaque formation in mice were detected.In addition,oxidative stress and mitochondrial structure and function changes in cells and mice were evaluated by transmission electron microscopy,JC-1 fluorescent probe,and Western blotting assays.The expression levels of proteins in the AMPK/Drp1 pathway were examined through Western blot.Results:OA markedly increased cell viability and migration rate of HUVECs,and decreased the adhesion rate of THP-1 cells and the apoptosis rate.OA significantly reduced serum lipid levels,such as total cholesterol and triglyceride,in mice and inhibited plaque formation in the aorta.OA also significantly increased the content of superoxide dismutase and catalase,alleviated mitochondrial damage,such as mitochondrial swelling and mitochondrial cristae reduction,reduced the number of mitochondria,increased adenosine triphosphate content,and significantly reduced p-Drp1(Ser616)/Drp1,MFF and FIS1 levels,increased p-AMPK/AMPK levels,activated AMPK,and then regulated DRP1 activity.Conclusions:OA activates AMPK,which in turn regulates the activity of DRP1 to restore normal mitochondrial dynamics and reduce atherosclerosis. 展开更多
关键词 Oleanolic acid AMPK/Drp1 pathway MITOCHONDRIA ATHEROSCLEROSIS Oxidative stress Endothelial cells
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Polysialic acid-Siglec immune checkpoints of microglia and macrophages:Perspectives for therapeutic intervention
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作者 Hauke Thiesler Herbert Hildebrandt 《Neural Regeneration Research》 2026年第2期661-662,共2页
Microglia are the resident macrophages of the central nervous system.They act as the first line of defense against pathogens and play essential roles in neuroinflammation and tissue repair after brain insult or in neu... Microglia are the resident macrophages of the central nervous system.They act as the first line of defense against pathogens and play essential roles in neuroinflammation and tissue repair after brain insult or in neurodegenerative and demyelinating diseases(Borst et al.,2021).Together with infiltrating monocyte-derived macrophages,microglia also play a critical role for brain tumor development,since immunosuppressive interactions between tumor cells and tumor-associated microglia and macrophages(TAM)are linked to malignant progression.This mechanism is of particular relevance in glioblastoma(GB),the deadliest form of brain cancer with a median overall survival of less than 15 months(Khan et al.,2023).Therefore,targeting microglia and macrophage activation is a promising strategy for therapeutic interference in brain disease. 展开更多
关键词 therapeutic intervention central nervous system immune checkpoints neurodegenerative demyelinating diseases borst MACROPHAGES polysialic acid SIGLEC MICROGLIA
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Potential role of astrocyte on gamma-aminobutyric acid tone regulation during developmental period
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作者 Erva Ozkan Wuhyun Koh 《Neural Regeneration Research》 2026年第3期1118-1119,共2页
The early developmental period is a critical window during which brain cells mature and contribute to both brain development and later life functions.Gamma-aminobutyric acid(GABA),recognized as a major neurotransmitte... The early developmental period is a critical window during which brain cells mature and contribute to both brain development and later life functions.Gamma-aminobutyric acid(GABA),recognized as a major neurotransmitter,plays a crucial role in coordinating synapse formation,neuronal proliferation,and migration during this time. 展开更多
关键词 early developmental period developmental period brain cells neuronal proliferation synapse formation gamma aminobutyric acid ASTROCYTE GABA
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Effect of Fulvic Acid on Growth and Yield Components of Direct Seeding Rice 被引量:3
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作者 王晓琳 苏云 +1 位作者 许晓明 李贵 《Agricultural Science & Technology》 CAS 2013年第7期966-972,共7页
ObjectiveThis study aimed to investigate the effect of fulvic acid on the growth and yield components of direct seeding rice (Nanjing 44). MethodThe rice seeds were soaked in 0 (water as a control), 1, 2, 4 and 6 ... ObjectiveThis study aimed to investigate the effect of fulvic acid on the growth and yield components of direct seeding rice (Nanjing 44). MethodThe rice seeds were soaked in 0 (water as a control), 1, 2, 4 and 6 g/L fulvic acid (FA) before sowed. Then, the rice morphological indices, leaf chlorophyll content, photosynthesis parameters, root activity and chlorophyll fluorescence parameters were measured in the following field studies. ResultCompared with the control, the leaf area index, chlorophyll content, net photosynthetic rate, stomatal conductance and dry matter weight and some fluorescence parameters such as the maximum photochemical efficiency of photosystem II (PSII) (Fv/Fm), excitation energy capture efficiency of opened PSII reaction center (Fv’/Fm’) and efficiency of the open reaction centre (ΦPS II) increased by different levels at both jointing stage and heading stage of direct seeding rice, whose seeds were soaked by FA with different concentrations. High FA concentration (4-6 g/L) significantly increased the cultivated rice leaf area index, chlorophyll content, net photosynthetic rate, stomatal conductance, transpiration rate and dry matter weight by 10.32% -22.88% , 5.88% -13.11% , 12.16% -26.84% , 11.43% -88.46% , 10.63% -21.63% , 18.49% -19.68% , respectively, thereby improving the physiological function and light energy transform efficiency of rice at the growth stage. With FA concentration increasing, the yield, effective panicles, grain number per panicle and seed setting rate were increased significantly compared with the control by 17.52%-18.71%, 3.46%-3.85%, 6.30%- 6.51% and 7.82%-8.69% respectively. ConclusionSoaking rice seed with FA could be considered as an effective way to improve the rice competitiveness at early growth stage. 展开更多
关键词 Fulvic acid Direct seeding rice Growth and development Yield components
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A Review on Tibetan Swine(a)——Carcass,Meat Quality,Basic Nutrition Component,Amino Acids,Fatty Acids,Inosine Monophosphate and Muscle Fiber 被引量:4
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作者 王蜀金 李嘉英 +3 位作者 王欢 韩帅娟 郭春华 王永 《Agricultural Science & Technology》 CAS 2013年第10期1369-1374,1391,共7页
In this review, the carcass, meat quality, internal organs, basic nutrition component, amino acids (AAs), fatty acids, inosine monophosphate (IMP) and mus- cle fiber of Tibetan swine were summarized for the first ... In this review, the carcass, meat quality, internal organs, basic nutrition component, amino acids (AAs), fatty acids, inosine monophosphate (IMP) and mus- cle fiber of Tibetan swine were summarized for the first time. The formation mecha- nism of excellent features was analyzed from the aspects of physiological traits, ge- ographical environments and constraint reasons. Thereby, the outstanding features of Tibetan swine could be extended continuously, and the poor characteristics should be improved in the future. 展开更多
关键词 Tibetan swine Meat quality Amino acids Fatty acids Muscle fiber
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Solid components and acid buffering capacity of soils in South China 被引量:6
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作者 Qiu Rong liang, Wu Qing, Zhang Yun ni Department of Environmental Science, Zhongshan University, Guangzhou 510275, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1998年第2期42-48,共7页
The effects of soil solid components on soil sensitivity to acid deposition by sequential extraction method were studied. A multiple regression equation of soil sensitivity was set up on the basis of stepwise regressi... The effects of soil solid components on soil sensitivity to acid deposition by sequential extraction method were studied. A multiple regression equation of soil sensitivity was set up on the basis of stepwise regression analysis. The results showed that organic matter expressed dual effects that were decided by soil original pH value and exchangeable cation composition on acid buffering reactions. The hydrolysis of activated oxides was a very important proton buffering reaction when in low pH situation. The crystalline oxides also played a role in the buffering reactions, but the role was restricted by the rate of activation of oxides. Meanwhile, the results by stepwise analysis showed that factors that had significant effect on soil acid buffering capacity were content of montmorillite, soil original pH value, Al 0, Mn 0 and CEC in decreasing order. Finally, sixteen soils were classified into four types of sensitive with single index cluster and multiple fuzzy cluster analysis respectively. 展开更多
关键词 acid deposition acid buffering capacity soil sensitivity solid components.
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High Temperature During Rice Grain Filling Enhances Aspartate Metabolism in Grains and Results in Accumulation of AspartateFamily Amino Acids and Protein Components 被引量:6
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作者 LIANG Cheng-gang ZHANG Qing +3 位作者 XU Guang-li WANG Yan Ryu OHSUGI LI Tian 《Rice science》 SCIE 2013年第5期343-348,共6页
Global warming causes the exacerbation of rice growing environment, which seriously affects rice growth and reproduction, and finally results in the decrease of rice yield and quality. We investigated the activities o... Global warming causes the exacerbation of rice growing environment, which seriously affects rice growth and reproduction, and finally results in the decrease of rice yield and quality. We investigated the activities of aspartate metabolism enzymes in grains, and the contents of Aspartate-family amino acids and protein components to further understand the effects of high temperature (HT) on rice nutritional quality during rice grain filling. Under HT, the average activities of aspartate aminotransferase (AAT) and aspartokinase (AK) in grains significantly increased, the amino acid contents of aspartate (Asp), lysine (Lys), threonine (Thr), methionine (Met) and isoleucine (lie) and the protein contents of albumin, globulin, prolamin and glutelin also significantly increased. The results indicated that HT enhanced Asp metabolism during rice grain filling and the enhancement of Asp metabolism might play an important role in the increase of Asp-family amino acids and protein components in grains. In case of the partial appraisal of the change of Asp-family amino acids and protein components under HT, we introduced eight indicators (amino acid or protein content, ratio of amino acid or protein, amino acid or protein content per grain and amino acid or protein content per panicle) to estimate the effects of HT. It is suggested that HT during rice grain filling was benefit for the accumulation of Asp-family amino acids and protein components. Combined with the improvement of Asp-family amino acid ratio in grains under HT, it is suggested that HT during grain filling may improve the rice nutritional quality. However, the yields of parts of Asp-family amino acids and protein components were decreased under HT during rice grain filling. 展开更多
关键词 high temperature aspartate aminotransferase ASPARTOKINASE aspartate-family amino acid protein component
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Effects of urea enhanced with different weathered coal-derived humic acid components on maize yield and fate of fertilizer nitrogen 被引量:17
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作者 ZHANG Shui-qin YUAN Liang +4 位作者 LI Wei LIN Zhi-an LI Yan-ting HU Shu-wen ZHAO Bing-qiang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第3期656-666,共11页
Humic acid(HA) is a readily available and low-cost material that is used to enhance crop production and reduce nitrogen(N) loss. However, there is little consensus on the efficacy of different HA components. In the cu... Humic acid(HA) is a readily available and low-cost material that is used to enhance crop production and reduce nitrogen(N) loss. However, there is little consensus on the efficacy of different HA components. In the current study, a soil column experiment was conducted using the ^(15)N tracer technique in Dezhou City, Shandong Province, China, to compare the effects of urea with and without the addition of weathered coal-derived HA components on maize yield and the fate of fertilizerderived N(fertilizer N). The HA components were incorporated into urea by blending different HA components into molten urea to obtain the three different types of HA-enhanced urea(HAU). At harvest, the aboveground dry biomass of plants grown with HAU was enhanced by 11.50–21.33% when compared to that of plants grown with U. More significantly, the grain yields under the HAU treatments were 5.58–18.67% higher than the yield under the urea treatment. These higher yields were due to an increase in the number of kernels per plant rather than the weight of individual kernels. The uptake of fertilizer N under the HAU treatments was also higher than that under the urea treatment by 11.49–29.46%, while the unaccounted N loss decreased by 12.37–30.05%. More fertilizer-derived N was retained in the 0–30 cm soil layer under the HAU treatments than that under the urea treatment, while less N was retained in the 30–90 cm soil layer. The total residual amount of fertilizer N in the soil column, however, did not differ significantly between the treatments. Of the three HAU treatments investigated, the one with an HA fraction derived from extraction with pH values ranging from 6 to 7, resulted in the best improvement in all assessment targets. This is likely due to the abundance of the COO/C–N=O group in this HA component. 展开更多
关键词 HUMIC acid ENHANCED UREA maize ABOVEGROUND dry biomass FERTILIZER N uptake FERTILIZER N residue
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One-pot five-component synthesis of highly functionalized piperidines using oxalic acid dihydrate as a homogenous catalyst 被引量:2
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作者 Seyed Sajad Sajadikhah Malek Taher Maghsoodlou +2 位作者 Nourallah Hazeri Sayyed Mostafa Habibi-Khorassani Anthony C.Willis 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第5期569-572,共4页
An efficient green protocol is described for the preparation of highly functionalized piperidines via a one-pot five-component reaction between aromatic aldehydes,anilines andβ-ketoesters in the presence of oxalic ac... An efficient green protocol is described for the preparation of highly functionalized piperidines via a one-pot five-component reaction between aromatic aldehydes,anilines andβ-ketoesters in the presence of oxalic acid dihydrate as catalyst in ethanol at ambient temperature.The structure as well as the relative stereochemistry of these compounds was confirmed by single X-ray crystallographic analysis. 展开更多
关键词 PIPERIDINE HETEROCYCLE Homogeneous catalyst Oxalic acid dihydrate Multi-component reaction
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A convenient one-pot three component synthesis of 3-aminoalkylated indoles catalyzed by 3-chlorophenylboronic acid 被引量:6
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作者 Santosh V.Goswami Prashant.B.Thorat +2 位作者 Vijay N.Kadam Sachin A.Khiste Sudhakar R.Bhusare 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第5期422-424,共3页
An efficient protocol was developed for the synthesis of 3-aminoalkylated indoles using 3- chlorophenylboronic acid as a catalyst under ambient temperature conditions.The three-component reaction of indoles,aromatic a... An efficient protocol was developed for the synthesis of 3-aminoalkylated indoles using 3- chlorophenylboronic acid as a catalyst under ambient temperature conditions.The three-component reaction of indoles,aromatic aldehydes and N-methyl aniline offered corresponding 3-aminoalkylated indoles in excellent yields.This protocol presents some remarkable features such as mild reaction conditions,simple workup procedure and excellent yields. 展开更多
关键词 3-Aminoalkylaed indoles 3-Chlorophenylboronic acid Aromatic aldehyde N-METHYLANILINE INDOLES
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Oxalic acid as a simple and efficient organocatalyst for three-component synthesis ofα-amino nitriles 被引量:2
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作者 Seyed Mohammad Vahdat Samad Khaksar Maryam Khavarpour 《Chinese Chemical Letters》 SCIE CAS CSCD 2011年第5期543-546,共4页
A simple,efficient,and general method has been developed for the synthesis ofα-amino nitriles.Oxalic acid as a BrФnsted acid promotes the addition of TMSCN to various imines(generated in situ).
关键词 Oxalic acid TMSCN BrФnsted acid α-Amino nitriles
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