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NMR Studies of a New Binding Mode of the Amino Acid Esters by Porphyrinatozinc(Ⅱ)
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作者 PENG Xiao-bin HUANG Jin-wang +1 位作者 LI Tao JI Liang-nian 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2001年第1期1-5,共5页
The binding mode of the amino acid ethyl esters(guest) by 5 (2 carboxylphenyl) 10,15,20 triphenylporphyrinatozinc(Ⅱ)(host 1) was studied by means of 1H NMR spectra. The binding mode is the hydrogen bonding between th... The binding mode of the amino acid ethyl esters(guest) by 5 (2 carboxylphenyl) 10,15,20 triphenylporphyrinatozinc(Ⅱ)(host 1) was studied by means of 1H NMR spectra. The binding mode is the hydrogen bonding between the amino group of the guest and the carboxyl group of host 1 plus the coordination between the zinc atom of porphyrinatozinc(Ⅱ) and the carbonyl group of the guest. This is a novel binding mode of the metalloporphyrin to amino acid derivatives. 展开更多
关键词 H NMR Porphyrinatozinc(Ⅱ) amino acid ester New binding mode
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Studies on Models,Patterns and Requirements of Digestible Amino Acids for Layers by Nitrogen Metabolism
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作者 Yin Qingciang, Han Youwen, Fan Shijun ( Laboratory of Animal Nutrition, Veterinary Institute, Changchun University of Agriculture and Animal Science, 175 Xi an Road, Changchun, China, and Department of Animal Science, Northeast Agricultural Uni 《Journal of Northeast Agricultural University(English Edition)》 CAS 1999年第1期15-25,共11页
The nitrogen (N) metabolic experiments were made to estimate separately amino acid requirements of 4348 weeks old layers for maintenance, for protein accretion to estabolish models to estimate digestible amino acid re... The nitrogen (N) metabolic experiments were made to estimate separately amino acid requirements of 4348 weeks old layers for maintenance, for protein accretion to estabolish models to estimate digestible amino acid requirements. The regression relationship of nitrogen retention vs amino acid intake was estimated for each amino acid by giving, at rate of N intake of 091, 052, 015 and 0007gkg-1 body-weight (W075) per d, the semi-synthetic diets was made specially deficient in one amino acid. From the regression coefficients, it was calculated that, for the accretion of 1 g protein, the dietary digestible amino acid requirements were (mg) Thr 631, Val 1004, Met 399, Ile 886, Leu 1143, Phe 632, Lys 870, His 205, Arg 879, Trp 214, Met+Cys 776, and Phe+Tyr 1143. Daily amino acid requirements for N equilibrium were estimated to be (mgkg-1W075 per day) Thr 506, Val 747, Met 303, ILe 667 Leu 814, Phe 448, Lys 605 His 147, Arg 739 ,Trp 173, Met+Cys 586, and Phe+Tyr 839 The dietary degestible amino acid patterns for protein accretion and N equilibrium were also proposed. The models of estimating digestible amino acid requirements for the different productions were developed. 展开更多
关键词 LAYERS amino acids PATTERNS MODELS nitrogen metabolism
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Direct Electron Transfer Reactions of Glucose Oxidase and D-Amino Acid Oxidase at a Glassy Carbon Electrode in Organic Media
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作者 Wei Jianjun Qin Yiqin Liu Haiying(School of Chemistry and Chemical Engineering) Deng Jiaqi(Fudan University) 《Advances in Manufacturing》 SCIE CAS 1998年第1期80-83,共4页
Cyclic voltammetry is employed to demonstrate feasibility of direct electron transfer of glucose oxidase and D amino acid oxidase at a glassy carbon electrode in organic media. The reversible slight conformational ch... Cyclic voltammetry is employed to demonstrate feasibility of direct electron transfer of glucose oxidase and D amino acid oxidase at a glassy carbon electrode in organic media. The reversible slight conformational change of glucose oxidase is observed by changing 0.1 mol/L phosphate buffer to acetonitrile containing 10% v/v of water and 0.05 mol/L tetrabutyalammonium perchlorate, and vice versa. 展开更多
关键词 glucose oxidase D amino acid oxidase direct electron transfer
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Effects of Nerve Growth Factor on Excitatory Amino Acid Content in Spinal Cord Neuron after Spinal Cord Injury
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作者 曹晓建 罗永湘 《The Journal of Biomedical Research》 CAS 1999年第1期20-22,共3页
To investigate the protective mechanism of nerve growth factor (NGF) on spinal cord injury (SCI), surgical spinal cord injury in Wistar rats was performed by a 10 g2.5 cm impact on the posterior spinal cord at T8 leve... To investigate the protective mechanism of nerve growth factor (NGF) on spinal cord injury (SCI), surgical spinal cord injury in Wistar rats was performed by a 10 g2.5 cm impact on the posterior spinal cord at T8 level, and a thin plastic tube was placed in subarachoid space below the injury level for perfusion of solution. To the experimental animals were given 60 g (20 l liquid) NGF, purified from bovine seminal plasma, at the moment of injury and 1,2,3,4,8,12,24 h after injury. An equal volume of normal saline was given to rats of the control group at the same time. In the expermental group, the injured spinal cord tissue was taken following treatment. The contents of the excitatory amino acids (Glu, Asp) were determined by high performance liquid chromatography (HPLC). Excitatory amino acid contents in the injured spinal cord were significantly increased at 10 min and 8 h after the injury as compared with those in the control group. However, The peak values of the excitatory amino acid contents in NGF group were obviously lowered. NGF might protect spinal cord against injury in vivo. One of the possible mechanisms is that NGF prohibits neurotoxicity of the exitatory amino acids. 展开更多
关键词 spinal cord injury nerve growth factor excitatory amino acid
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Analysis of amino acid constituents of gallstones
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作者 CHEN Ying1, WANG LianLian1, XIAO YuXia2, NI JingHua2 and YU Yan2 《World Journal of Gastroenterology》 SCIE CAS CSCD 1997年第4期57-58,共2页
IM To seek effective drugs to dissolve bilirubin, glycoprotein and black stones and better lithotriptics for cholesterol stones, and study the amino acid constituents of gallstones.METHODS According to the character... IM To seek effective drugs to dissolve bilirubin, glycoprotein and black stones and better lithotriptics for cholesterol stones, and study the amino acid constituents of gallstones.METHODS According to the characteristics of infrared spectrum and the contents of bilirubin tested by semiquantitative chemical analysis, 30 of 148 cases of gallstones were selected and divided into 5 groups. Amino acids of the 30 cases were detected by high speed chromatography.RESULTS The quantity of amino acids in black stones was the highest (2269mg/g) and that of pure cholesterol stones was the lowest, only 14mg/g in a case. In five groups of gallstones, the contents of amino acids were: black stone > mixed bilirubin stone and glucoprotein stone > mixed cholesterol stone > pure cholesterol stone. The proportions were: 9595∶2902 and 2805∶578∶1. Aliphatic amino acids accounted for about 50% of the total amino acids in gallstones and glycine 153% of the total amount of 17 kinds of amino acids.CONCLUSION In mixed stones, the higher level of bilirubin, the higher contents of amino acids. The acidic amino acids of bilirubin stones were relatively higher than those of cholesterol stones. 展开更多
关键词 GALLSTONES amino acids/analysis BILIRUBIN GLYCINE
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Protective Effect of Tetrandrine against Excitatory Amino Acids induced Neuronal Injury in Cortical Culture
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作者 车建途 张均田 +1 位作者 陈飞松 屈志炜 《Journal of Chinese Pharmaceutical Sciences》 CAS 1997年第3期31-36,共6页
The ability of tetrandrine (Tet), an alkaloid isolated from Radix Stephaniae Tetrandrae, to reduce cortical neuronal injury in cortical cultures derived from fetal rats was quantitatively assessed by examination of mo... The ability of tetrandrine (Tet), an alkaloid isolated from Radix Stephaniae Tetrandrae, to reduce cortical neuronal injury in cortical cultures derived from fetal rats was quantitatively assessed by examination of morphological changes and measurement of lactate dehydrogenase (LDH) released to the extracellular bathing media Cell cultures exposed to the excitatory amino acids (EAA) 50 μmol L 1 glutamate (Glu), 20 μmol L 1 N methyl D aspartate (NMDA), 300 μmol·L 1 β N oxalylamino L alanine (BMAA, NMDA receptor agonist) or 20 μmol·L 1 β N oxaly lamino L alanine (BOAA, non NMDA receptor agonist) for 24 h at 37℃ showed widespread neuronal injury Tet had little effect on the injury induced by 20 μmol·L 1 NMDA but 10 7 and 10 6 μmol·L 1 Tet did partially attenuate the neuronal degeneration, neuronal loss and LDH efflux resulting from prolonged exposures to 100 μmol·L 1 Glu, 300 μmol·L 1 BMAA and 20 μmol·L 1 BOAA respectively The ability of Tet to reduce the neuronal injury induced by prolonged exposure to EAA may contribute, at least in part, to the reduction of Ca 2+ influx through inhibiting the opening of voltagegated Ca 2+ channels Another mechanism that Tet might have a little inhibitory effect on NMDA receptor on neuronal membrane cannot be excluded, as BMAA has been considered to act as a weak NMDA receptor agonist 展开更多
关键词 TETRANDRINE Cortical neuronal culture Intracellular Ca 2+ Excitatory amino acids
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Gut microbiota induced abnormal amino acids and their correlation with diabetic retinopathy 被引量:1
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作者 Sheng-Qun Jiang Su-Na Ye +4 位作者 Yin-Hua Huang Yi-Wen Ou Ke-Yang Chen Jian-Su Chen Shi-Bo Tang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第5期883-895,共13页
AIM:To explore the correlation of gut microbiota and the metabolites with the progression of diabetic retinopathy(DR)and provide a novel strategy to elucidate the pathological mechanism of DR.METHODS:The fecal samples... AIM:To explore the correlation of gut microbiota and the metabolites with the progression of diabetic retinopathy(DR)and provide a novel strategy to elucidate the pathological mechanism of DR.METHODS:The fecal samples from 32 type 2 diabetes patients with proliferative retinopathy(PDR),23 with nonproliferative retinopathy(NPDR),27 without retinopathy(DM),and 29 from the sex-,age-and BMI-matched healthy controls(29 HC)were analyzed by 16S rDNA gene sequencing.Sixty fecal samples from PDR,DM,and HC groups were assayed by untargeted metabolomics.Fecal metabolites were measured using liquid chromatographymass spectrometry(LC-MS)analysis.Associations between gut microbiota and fecal metabolites were analyzed.RESULTS:A cluster of 2 microbiome and 12 metabolites accompanied with the severity of DR,and the close correlation of the disease progression with PDR-related microbiome and metabolites were found.To be specific,the structure of gut microbiota differed in four groups.Diversity and richness of gut microbiota were significantly lower in PDR and NPDR groups,than those in DM and HC groups.A cluster of microbiome enriched in PDR group,including Pseudomonas,Ruminococcaceae-UCG-002,Ruminococcaceae-UCG-005,Christensenellaceae-R-7,was observed.Functional analysis showed that the glucose and nicotinate degradations were significantly higher in PDR group than those in HC group.Arginine,serine,ornithine,and arachidonic acid were significantly enriched in PDR group,while proline was enriched in HC group.Functional analysis illustrated that arginine biosynthesis,lysine degradation,histidine catabolism,central carbon catabolism in cancer,D-arginine and D-ornithine catabolism were elevated in PDR group.Correlation analysis revealed that Ruminococcaceae-UCG-002 and Christensenellaceae-R-7 were positively associated with L-arginine,ornithine levels in fecal samples.CONCLUSION:This study elaborates the different microbiota structure in the gut from four groups.The relative abundance of Ruminococcaceae-UCG-002 and Parabacteroides are associated with the severity of DR.Amino acid and fatty acid catabolism is especially disordered in PDR group.This may help provide a novel diagnostic parameter for DR,especially PDR. 展开更多
关键词 proliferative retinopathy gut microbiota Ruminococcaceae amino acid metabolism ARGININE
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Metagenomic analysis revealing the metabolic role of microbial communities in the free amino acid biosynthesis of Monascus rice vinegar during fermentation 被引量:1
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作者 Hang Gao Jian Zhang +4 位作者 Li Liu Lijun Fu Yan Zhao Germán Mazza Xin Zhang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2317-2326,共10页
Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic netw... Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic network on FAA biosynthesis remains unclear.Through metagenomic analysis,this work aimed to elucidate the roles of microbes in FAA biosynthesis during Monascus rice vinegar fermentation.Taxonomic profiles from functional analyses showed 14 dominant genera with high contributions to the metabolism pathways.The metabolic network for FAA biosynthesis was then constructed,and the microbial distribution in different metabolic pathways was illuminated.The results revealed that 5 functional genera were closely involved in FAA biosynthesis.This study illuminated the metabolic roles of microorganisms in FAA biosynthesis and provided crucial insights into the functional attributes of microbiota in vinegar fermentation. 展开更多
关键词 Monascus rice vinegar Metagenomic analysis Free amino acid synthesis Metabolic pathway Microbial distribution
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Effect of different drying methods on the amino acids,α-dicarbonyls and volatile compounds of rape bee pollen 被引量:1
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作者 Yanxiang Bi Jiabao Ni +6 位作者 Xiaofeng Xue Zidan Zhou Wenli Tian Valérie Orsat Sha Yan Wenjun Peng Xiaoming Fang 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期517-527,共11页
The significant demand for high quality food has motivated us to adopt appropriate processing methods to improve the food nutritional quality and flavors.In this study,the effects of five drying methods,namely,pulsed ... The significant demand for high quality food has motivated us to adopt appropriate processing methods to improve the food nutritional quality and flavors.In this study,the effects of five drying methods,namely,pulsed vacuum drying(PVD),freeze drying(FD),infrared drying(IRD),hot-air drying(HAD)and sun drying(SD)on free amino acids(FAAs),α-dicarbonyl compounds(α-DCs)and volatile compounds(VOCs)in rape bee pollen(RBP)were determined.The results showed that FD significantly released the essential amino acids(EAAs)compared with fresh samples while SD caused the highest loss.Glucosone was the dominantα-DCs in RBP and the highest loss was observed after PVD.Aldehydes were the dominant volatiles of RBP and SD samples contained more new volatile substances(especially aldehydes)than the other four drying methods.Comprehensively,FD and PVD would be potential methods to effectively reduce the quality deterioration of RBP in the drying process. 展开更多
关键词 DRYING Bee pollen Free amino acids α-Dicarbonyl compounds Volatile compounds
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Decoding the nexus:branched-chain amino acids and their connection with sleep,circadian rhythms,and cardiometabolic health
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作者 Hui Li Laurent Seugnet 《Neural Regeneration Research》 SCIE CAS 2025年第5期1350-1363,共14页
The sleep-wake cycle stands as an integrative process essential for sustaining optimal brain function and,either directly or indirectly,overall body health,encompassing metabolic and cardiovascular well-being.Given th... The sleep-wake cycle stands as an integrative process essential for sustaining optimal brain function and,either directly or indirectly,overall body health,encompassing metabolic and cardiovascular well-being.Given the heightened metabolic activity of the brain,there exists a considerable demand for nutrients in comparison to other organs.Among these,the branched-chain amino acids,comprising leucine,isoleucine,and valine,display distinctive significance,from their contribution to protein structure to their involvement in overall metabolism,especially in cerebral processes.Among the first amino acids that are released into circulation post-food intake,branched-chain amino acids assume a pivotal role in the regulation of protein synthesis,modulating insulin secretion and the amino acid sensing pathway of target of rapamycin.Branched-chain amino acids are key players in influencing the brain's uptake of monoamine precursors,competing for a shared transporter.Beyond their involvement in protein synthesis,these amino acids contribute to the metabolic cycles ofγ-aminobutyric acid and glutamate,as well as energy metabolism.Notably,they impact GABAergic neurons and the excitation/inhibition balance.The rhythmicity of branchedchain amino acids in plasma concentrations,observed over a 24-hour cycle and conserved in rodent models,is under circadian clock control.The mechanisms underlying those rhythms and the physiological consequences of their disruption are not fully understood.Disturbed sleep,obesity,diabetes,and cardiovascular diseases can elevate branched-chain amino acid concentrations or modify their oscillatory dynamics.The mechanisms driving these effects are currently the focal point of ongoing research efforts,since normalizing branched-chain amino acid levels has the ability to alleviate the severity of these pathologies.In this context,the Drosophila model,though underutilized,holds promise in shedding new light on these mechanisms.Initial findings indicate its potential to introduce novel concepts,particularly in elucidating the intricate connections between the circadian clock,sleep/wake,and metabolism.Consequently,the use and transport of branched-chain amino acids emerge as critical components and orchestrators in the web of interactions across multiple organs throughout the sleep/wake cycle.They could represent one of the so far elusive mechanisms connecting sleep patterns to metabolic and cardiovascular health,paving the way for potential therapeutic interventions. 展开更多
关键词 branched-chain amino acids cardiovascular health circadian clock DROSOPHILA INSULIN metabolism SLEEP γ-aminobutyric acid
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Effects of improved amino acid balance diet on lysine mammary utilization, whole body protein turnover and muscle protein breakdown on lactating sows
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作者 Sai Zhang Juan C.Marini +4 位作者 Vengai Mavangira Andrew Claude Julie Moore Mahmoud A.Mohammad Nathalie L.Trottier 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期2031-2043,共13页
Background The study objective was to test the hypothesis that low crude protein(CP)diet with crystalline amino acids(CAA)supplementation improves Lys utilization efficiency for milk production and reduces protein tur... Background The study objective was to test the hypothesis that low crude protein(CP)diet with crystalline amino acids(CAA)supplementation improves Lys utilization efficiency for milk production and reduces protein turnover and muscle protein breakdown.Eighteen lactating multiparous Yorkshire sows were allotted to 1 of 2 isocaloric diets(10.80 MJ/kg net energy):control(CON;19.24%CP)and reduced CP with“optimal”AA profile(OPT;14.00%CP).Sow body weight and backfat were recorded on d 1 and 21 of lactation and piglets were weighed on d 1,14,18,and 21 of lactation.Between d 14 and 18,a subset of 9 sows(CON=4,OPT=5)was infused with a mixed solution of 3-[methyl-2H3]histidine(bolus injection)and[13C]bicarbonate(priming dose)first,then a constant 2-h[13C]bicarbonate infusion followed by a 6-h primed constant[1-13C]lysine infusion.Serial blood and milk sampling were performed to determine plasma and milk Lys enrichment,Lys oxidation rate,whole body protein turnover,and muscle protein breakdown.Results Over the 21-d lactation period,compared to CON,sows fed OPT had greater litter growth rate(P<0.05).Compared to CON,sows fed OPT had greater efficiency of Lys(P<0.05),Lys mammary flux(P<0.01)and whole-body protein turnover efficiency(P<0.05).Compared to CON,sows fed OPT tended to have lower whole body protein breakdown rate(P=0.069).Muscle protein breakdown rate did not differ between OPT and CON(P=0.197).Conclusion Feeding an improved AA balance diet increased efficiency of Lys and reduced whole-body protein turnover and protein breakdown.These results imply that the lower maternal N retention observed in lactating sows fed improved AA balance diets in previous studies may be a result of greater partitioning of AA towards milk rather than greater body protein breakdown. 展开更多
关键词 amino acid Efficiency Lactating sows Protein breakdown Protein turnover Reduced protein diet
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Low crude protein formulation with supplemental amino acids for its impacts on intestinal health and growth performance of growing-finishing pigs
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作者 Marcos Elias Duarte Wanpuech Parnsen +2 位作者 Shihai Zhang Marvio L.T.Abreu Sung Woo Kim 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第4期1590-1606,共17页
Background Low crude protein(CP)formulations with supplemental amino acids(AA)are used to enhance intestinal health,reduce costs,minimize environmental impact,and maintain growth performance of pigs.However,extensive ... Background Low crude protein(CP)formulations with supplemental amino acids(AA)are used to enhance intestinal health,reduce costs,minimize environmental impact,and maintain growth performance of pigs.However,extensive reduction of dietary CP can compromise growth performance due to limited synthesis of non-essential AA and limited availability of bioactive compounds from protein supplements even when AA requirements are met.Moreover,implementing a low CP formulation can increase the net energy(NE)content in feeds causing excessive fat deposition.Additional supplementation of functional AA,coupled with low CP formulation could further enhance intestinal health and glucose metabolism,improving nitrogen utilization,and growth performance.Three experiments were conducted to evaluate the effects of low CP formulations with supplemental AA on the intestinal health and growth performance of growing-finishing pigs.Methods In Exp.1,90 pigs(19.7±1.1 kg,45 barrows and 45 gilts)were assigned to 3 treatments:CON(18.0%CP,supplementing Lys,Met,and Thr),LCP(16.0%CP,supplementing Lys,Met,Thr,Trp,and Val),and LCPT(16.1%CP,LCP+0.05%SID Trp).In Exp.2,72 pigs(34.2±4.2 kg BW)were assigned to 3 treatments:CON(17.7%CP,meeting the requirements of Lys,Met,Thr,and Trp);LCP(15.0%CP,meeting Lys,Thr,Trp,Met,Val,Ile,and Phe);and VLCP(12.8%CP,meeting Lys,Thr,Trp,Met,Val,Ile,Phe,His,and Leu).In Exp.3,72 pigs(54.1±5.9 kg BW)were assigned to 3 treatments and fed experimental diets for 3 phases(grower 2,finishing 1,and finishing 2).Treatments were CON(18.0%,13.8%,12.7%CP for 3 phases;meeting Lys,Met,Thr,and Trp);LCP(13.5%,11.4%,10.4%CP for 3 phases;meeting Lys,Thr,Trp,Met,Val,Ile,and Phe);and LCPG(14.1%,12.8%,11.1%CP for 3 phases;LCP+Glu to match SID Glu with CON).All diets had 2.6 Mcal/kg NE.Results In Exp.1,overall,the growth performance did not differ among treatments.The LCPT increased(P<0.05)Claudin-1 expression in the duodenum and jejunum.The LCP and LCPT increased(P<0.05)CAT-1,4F2hc,and B0AT expressions in the jejunum.In Exp.2,overall,the VLCP reduced(P<0.05)G:F and BUN.The LCP and VLCP increased(P<0.05)the backfat thickness(BFT).In Exp.3,overall,growth performance and BFT did not differ among treatments.The LCPG reduced(P<0.05)BUN,whereas increased the insulin in plasma.The LCP and LCPG reduced(P<0.05)the abundance of Streptococcaceae,whereas the LCP reduced(P<0.05)Erysipelotrichaceae,and the alpha diversity.Conclusions When implementing low CP formulation,CP can be reduced by supplementation of Lys,Thr,Met,Trp,Val,and Ile without affecting the growth performance of growing-finishing pigs when NE is adjusted to avoid increased fat deposition.Supplementation of Trp above the requirement or supplementation of Glu in low CP formulation seems to benefit intestinal health as well as improved nitrogen utilization and glucose metabolism. 展开更多
关键词 amino acids Growing-finishing pigs Growth performance Intestinal health Low crude protein formulation Net energy
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Stabilizing perovskite precursors with the reductive natural amino acid for printable mesoscopic perovskite solar cells
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作者 Wenjing Hu Jian Yang +9 位作者 Chuang Yang Xufeng Xiao Chaoyang Wang Zhaozhen Cui Qiaojiao Gao Jianhang Qi Minghao Xia Yaqiong Su Anyi Mei Hongwei Han 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期32-39,I0003,共9页
Solution processability significantly advances the development of highly-efficient perovskite solar cells.However,the precursor solution tends to undergo irreversible degradation reactions,impairing the device perform... Solution processability significantly advances the development of highly-efficient perovskite solar cells.However,the precursor solution tends to undergo irreversible degradation reactions,impairing the device performance and reproducibility.Here,we utilize a reductive natural amino acid,Nacetylcysteine(NALC),to stabilize the precursor solution for printable carbon-based hole-conductorfree mesoscopic perovskite solar cells.We find that I_(2) can be generated in the aged solution containing methylammonium iodide(MI) in an inert atmosphere and speed up the MA-FA^(+)(formamidinium) reaction which produces large-size cations and hinders the formation of perovskite phase.NALC effectively stabilizes the precursor via its sulfhydryl group which reduces I_(2) back to I^(-)and provides H^(+).The NALC-stabilized precursor which is aged for 1440 h leads to devices with a power conversion efficiency equivalent to 98% of that for devices prepared with the fresh precursor.Furthermore,NALC improves the device power conversion efficiency from 16.16% to 18.41% along with enhanced stability under atmospheric conditions by modifying grain boundaries in perovskite films and reducing associated defects. 展开更多
关键词 Perovskite solar cells Perovskite precursor Degradation STABILIZATION Reductive natural amino acid
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Increased excitatory amino acid transporter 2 levels in basolateral amygdala astrocytes mediate chronic stress–induced anxiety-like behavior
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作者 Xirong Xu Shoumin Xuan +3 位作者 Shuai Chen Dan Liu Qian Xiao Jie Tu 《Neural Regeneration Research》 SCIE CAS 2025年第6期1721-1734,共14页
The conventional perception of astrocytes as mere supportive cells within the brain has recently been called into question by empirical evidence, which has revealed their active involvement in regulating brain functio... The conventional perception of astrocytes as mere supportive cells within the brain has recently been called into question by empirical evidence, which has revealed their active involvement in regulating brain function and encoding behaviors associated with emotions.Specifically, astrocytes in the basolateral amygdala have been found to play a role in the modulation of anxiety-like behaviors triggered by chronic stress. Nevertheless, the precise molecular mechanisms by which basolateral amygdala astrocytes regulate chronic stress–induced anxiety-like behaviors remain to be fully elucidated. In this study, we found that in a mouse model of anxiety triggered by unpredictable chronic mild stress, the expression of excitatory amino acid transporter 2 was upregulated in the basolateral amygdala. Interestingly, our findings indicate that the targeted knockdown of excitatory amino acid transporter 2 specifically within the basolateral amygdala astrocytes was able to rescue the anxiety-like behavior in mice subjected to stress. Furthermore, we found that the overexpression of excitatory amino acid transporter 2 in the basolateral amygdala, whether achieved through intracranial administration of excitatory amino acid transporter 2agonists or through injection of excitatory amino acid transporter 2-overexpressing viruses with GfaABC1D promoters, evoked anxiety-like behavior in mice. Our single-nucleus RNA sequencing analysis further confirmed that chronic stress induced an upregulation of excitatory amino acid transporter 2 specifically in astrocytes in the basolateral amygdala. Moreover, through in vivo calcium signal recordings, we found that the frequency of calcium activity in the basolateral amygdala of mice subjected to chronic stress was higher compared with normal mice.After knocking down the expression of excitatory amino acid transporter 2 in the basolateral amygdala, the frequency of calcium activity was not significantly increased, and anxiety-like behavior was obviously mitigated. Additionally, administration of an excitatory amino acid transporter 2 inhibitor in the basolateral amygdala yielded a notable reduction in anxiety level among mice subjected to stress. These results suggest that basolateral amygdala astrocytic excitatory amino acid transporter 2 plays a role in in the regulation of unpredictable chronic mild stress-induced anxiety-like behavior by impacting the activity of local glutamatergic neurons, and targeting excitatory amino acid transporter 2 in the basolateral amygdala holds therapeutic promise for addressing anxiety disorders. 展开更多
关键词 ANXIETY ASTROCYTES basolateral amygdala behavior dihydrokainic acid excitatory amino acid transporter 2 fiber photometry GLUTAMATE LDN-212320 TRANSPORTER
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Targeting harmful effects of non-excitatory amino acids as an alternative therapeutic strategy to reduce ischemic damage
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作者 Victoria Jiménez Carretero IrisÁlvarez-Merz +2 位作者 Jorge Hernández-Campano Sergei A.Kirov Jesús M.Hernández-Guijo 《Neural Regeneration Research》 SCIE CAS 2025年第9期2454-2463,共10页
The involvement of the excitatory amino acids glutamate and aspartate in ce rebral ischemia and excitotoxicity is well-documented.Nevertheless,the role of non-excitatory amino acids in brain damage following a stroke ... The involvement of the excitatory amino acids glutamate and aspartate in ce rebral ischemia and excitotoxicity is well-documented.Nevertheless,the role of non-excitatory amino acids in brain damage following a stroke or brain trauma remains largely understudied.The release of amino acids by necrotic cells in the ischemic core may contribute to the expansion of the penumbra.Our findings indicated that the reversible loss of field excitato ry postsynaptic potentials caused by transient hypoxia became irreversible when exposed to a mixture of just four non-excitatory amino acids(L-alanine,glycine,L-glutamine,and L-serine)at their plasma concentrations.These amino acids induce swelling in the somas of neurons and astrocytes during hypoxia,along with permanent dendritic damage mediated by N-methyl-D-aspartate receptors.Blocking N-methyl-D-aspartate receptors prevented neuronal damage in the presence of these amino acids during hypoxia.It is likely that astroglial swelling caused by the accumulation of these amino acids via the alanine-serine-cysteine transporter 2 exchanger and system N transporters activates volume-regulated anion channels,leading to the release of excitotoxins and subsequent neuronal damage through N-methyl-D-aspartate receptor activation.Thus,previously unrecognized mechanisms involving non-excitatory amino acids may contribute to the progression and expansion of brain injury in neurological emergencies such as stroke and traumatic brain injury.Understanding these pathways co uld highlight new therapeutic targets to mitigate brain injury. 展开更多
关键词 cell swelling N-methyl-D-aspartate receptor non-excitatory amino acids STROKE synaptic transmission
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Standardized ileal digestibility of amino acids in soybean meal fed to non-pregnant and pregnant sows
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作者 Ke Wang Ya Wang +11 位作者 Lei Guo Yong Zhuo Lun Hua Lianqiang Che Shengyu Xu Ruinan Zhang Jian Li Bin Feng Zhengfeng Fang Xuemei Jiang Yan Lin De Wu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期362-373,共12页
Background Two studies were designed to determine standard ileal crude protein(CP)and amino acid(AA)digestibility of soybean meal(SBM)from different origins fed to non-pregnant and pregnant sows.Seven solvent-extracte... Background Two studies were designed to determine standard ileal crude protein(CP)and amino acid(AA)digestibility of soybean meal(SBM)from different origins fed to non-pregnant and pregnant sows.Seven solvent-extracted SBMs from soybeans produced in the USA,Brazil,and China were selected.In Exp.1,eight different diets were created:a nitrogen(N)-free diet and 7 experimental diets containing SBM from different origins as the only N source.Eight non-pregnant,multiparous sows were arranged in an 8×8 Latin square design(8 periods and 8 diets).In Exp.2,the diet formula was the same as in Exp.1.Eight gestating sows(parity 3)were assigned to 4 different diets in a replicated 4×3 Youden square design(three periods and four diets)in mid-gestation and again in late-gestation stages.Results When fed to non-pregnant and late-gestating sows,the standardized ileal digestibility(SID)of CP and most AAs from different SBM were not significantly different(P>0.05).When fed to mid-gestating sows,the SID values for Arg,His,Lys,Phe,Cys,Gly,Ser,and Tyr in SBM 1 were lower than in SBM 4 and 5(P<0.05),whereas SID for Leu from SBM 5 was higher than in SBM 1 and 4(P<0.05).SID values for Ile,Ala,and Asp from SBM 4 were lower than in SBM 1 and 5(P<0.05).Sows had significantly greater SID values for Lys,Ala,and Asp during mid-gestation when compared with late-gestation stages(P<0.05).Mid-gestating sows had greater SID value for Val and lower SID value for Tyr when compared with non-pregnant and late-gestating sows(P<0.01),whereas non-pregnant sows had significantly greater SID value for Met when compared with gestating sows(P<0.01).Conclusions When fed to mid-gestating sows,the SID values for most AAs varied among SBM samples.The SID values for Lys,Met,Val,Ala,Asp,and Tyr in SBM were affected by sow gestation stages.Our findings provide a cornerstone for accurate SBM use in sow diets. 展开更多
关键词 amino acids SOWS Soybean meal Standardized ileal digestibility
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Abomasal infusion of branched-chain amino acids or branched-chain keto-acids alter lactation performance and liver triglycerides in fresh cows
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作者 Kristen Gallagher Isabelle Bernstein +7 位作者 Cynthia Collings David Main Ghayyoor Ahmad Sarah Naughton Jayasimha Daddam Vengai Mavangira Mike Vandehaar Zheng Zhou 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1145-1157,共13页
Background Dairy cows are at high risk of fatty liver disease in early lactation,but current preventative measures are not always effective.Cows with fatty liver have lower circulating branched-chain amino acid(BCAA)c... Background Dairy cows are at high risk of fatty liver disease in early lactation,but current preventative measures are not always effective.Cows with fatty liver have lower circulating branched-chain amino acid(BCAA)concentra-tions whereas cows with high circulating BCAA levels have low liver triglyceride(TG).Our objective was to determine the impact of BCAA and their corresponding ketoacids(branched-chain ketoacids,BCKA)on production performance and liver TG accumulation in Holstein cows in the first 3 weeks postpartum.Methods Thirty-six multiparous Holstein cows were used in a randomized block design experiment.Cows were abomasally infused for the first 21 d postpartum with solutions of 1)saline(CON,n=12);2)BCA(67 g valine,50 g leu-cine,and 34 g isoleucine,n=12);and 3)BCK(77 g 2-ketovaline calcium salt,57 g 2-ketoleucine calcium salt,and 39 g 2-ketoisoleucine calcium salt,n=12).All cows received the same diet.Treatment effects were determined using PROC GLIMMIX in SAS.Results No differences were detected for body weight,body condition score,or dry matter intake averaged over the first 21 d postpartum.Cows receiving BCK had significantly lower liver TG concentrations compared to CON(6.60%vs.4.77%,standard error of the mean(SEM)0.49)during the first 3 weeks of lactation.Infusion of BCA increased milk yield(39.5 vs.35.3 kg/d,SEM 1.8),milk fat yield(2.10 vs.1.69 kg/d,SEM 0.08),and lactose yield(2.11 vs.1.67 kg/d,SEM 0.07)compared with CON.Compared to CON,cows receiving BCA had lower plasma glucose(55.0 vs.59.2 mg/dL,SEM 0.86)but higherβ-hydroxybutyrate(9.17 vs.6.00 mg/dL,SEM 0.80).Conclusions Overall,BCAA supplementation in this study improved milk production,whereas BCKA supplementa-tion reduced TG accumulation in the liver of fresh cows. 展开更多
关键词 Branched-chain amino acids Branched-chain ketoacids Fatty liver Fresh cow
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Edaravone-loaded poly(amino acid) nanogel inhibits ferroptosis for neuroprotection in cerebral ischemia injury
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作者 Yunhan Zhang Zhulin Zou +5 位作者 Shuang Liu Fangfang Chen Minglu Li Haoyang Zou Haiyan Liu Jianxun Ding 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2024年第2期89-101,共13页
Neurological injury caused by ischemic stroke is a major cause of permanent disability and death. The currently available neuroprotective drugs fail to achieve desired therapeutic efficacy mainly due to short circulat... Neurological injury caused by ischemic stroke is a major cause of permanent disability and death. The currently available neuroprotective drugs fail to achieve desired therapeutic efficacy mainly due to short circulation half-life and poor blood−brain barrier (BBB) permeability. For that, an edaravone-loaded pH/glutathione (pH/GSH) dual-responsive poly(amino acid) nanogel (NG/EDA) was developed to improve the neuroprotection of EDA. The nanogel was triggered by acidic and EDA-induced high-level GSH microenvironments, which enabled the selective and sustained release of EDA at the site of ischemic injury. NG/EDA exhibited a uniform sub-spherical morphology with a mean hydrodynamic diameter of 112.3 ± 8.2 nm. NG/EDA efficiently accumulated at the cerebral ischemic injury site of permanent middle cerebral artery occlusion (pMCAO) mice, showing an efficient BBB crossing feature. Notably, NG/EDA with 50 µM EDA significantly increased neuron survival (29.3%) following oxygen and glucose deprivation by inhibiting ferroptosis. In addition, administering NG/EDA for 7 d significantly reduced infarct volume to 22.2% ± 7.2% and decreased neurobehavioral scores from 9.0 ± 0.6 to 2.0 ± 0.8. Such a pH/GSH dual-responsive nanoplatform might provide a unique and promising modality for neuroprotection in ischemic stroke and other central nervous system diseases. 展开更多
关键词 Poly(amino acid)nanogel Controlled drug delivery Inhibition of ferroptosis NEUROPROTECTION Cerebral ischenia injury therapy
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Heterogeneously elevated branched-chain/aromatic amino acids among new-onset type-2 diabetes mellitus patients are potentially skewed diabetes predictors
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作者 Min Wang Yang Ou +7 位作者 Xiang-Lian Yuan Xiu-Fang Zhu Ben Niu Zhuang Kang Bing Zhang Anwar Ahmed Guo-Qiang Xing Heng Su 《World Journal of Diabetes》 SCIE 2024年第1期53-71,共19页
BACKGROUND The lack of specific predictors for type-2 diabetes mellitus(T2DM)severely impacts early intervention/prevention efforts.Elevated branched-chain amino acids(BCAAs:Isoleucine,leucine,valine)and aromatic amin... BACKGROUND The lack of specific predictors for type-2 diabetes mellitus(T2DM)severely impacts early intervention/prevention efforts.Elevated branched-chain amino acids(BCAAs:Isoleucine,leucine,valine)and aromatic amino acids(AAAs:Tyrosine,tryptophan,phenylalanine)show high sensitivity and specificity in predicting diabetes in animals and predict T2DM 10-19 years before T2DM onset in clinical studies.However,improvement is needed to support its clinical utility.AIM To evaluate the effects of body mass index(BMI)and sex on BCAAs/AAAs in new-onset T2DM individuals with varying body weight.METHODS Ninety-seven new-onset T2DM patients(<12 mo)differing in BMI[normal weight(NW),n=33,BMI=22.23±1.60;overweight,n=42,BMI=25.9±1.07;obesity(OB),n=22,BMI=31.23±2.31]from the First People’s Hospital of Yunnan Province,Kunming,China,were studied.One-way and 2-way ANOVAs were conducted to determine the effects of BMI and sex on BCAAs/AAAs.RESULTS Fasting serum AAAs,BCAAs,glutamate,and alanine were greater and high-density lipoprotein(HDL)was lower(P<0.05,each)in OB-T2DM patients than in NW-T2DM patients,especially in male OB-T2DM patients.Arginine,histidine,leucine,methionine,and lysine were greater in male patients than in female patients.Moreover,histidine,alanine,glutamate,lysine,valine,methionine,leucine,isoleucine,tyrosine,phenylalanine,and tryptophan were significantly correlated with abdominal adiposity,body weight and BMI,whereas isoleucine,leucine and phenylalanine were negatively correlated with HDL.CONCLUSION Heterogeneously elevated amino acids,especially BCAAs/AAAs,across new-onset T2DM patients in differing BMI categories revealed a potentially skewed prediction of T2DM development.The higher BCAA/AAA levels in obese T2DM patients would support T2DM prediction in obese individuals,whereas the lower levels of BCAAs/AAAs in NW-T2DM individuals may underestimate T2DM risk in NW individuals.This potentially skewed T2DM prediction should be considered when BCAAs/AAAs are to be used as the T2DM predictor. 展开更多
关键词 Hyperaminoacidemia Branched-chain/aromatic amino acids New-onset type-2 diabetes Predictor Obesity SEX
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Six Amino Acids among Natural Moisturizing Factors Responsible for Skin Hydration: Improvement and Anti-Aging of Skin by Galactomyces Ferment Filtrate-PiteraTM Containing Skin Moisturizer
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作者 Kukizo Miyamoto Yoko Munakata +4 位作者 Keisuke Fujii Wang Summer Ley Yang Suda Sudarsana Masutaka Furue 《Journal of Cosmetics, Dermatological Sciences and Applications》 2024年第2期113-127,共15页
Background: Natural moisturizing factors (NMFs) are filaggrin-derived components in the cornified layer that are critical for maintaining healthy skin moisturization and barrier function. However, studies have reporte... Background: Natural moisturizing factors (NMFs) are filaggrin-derived components in the cornified layer that are critical for maintaining healthy skin moisturization and barrier function. However, studies have reported conflicting findings on the relationship between NMF levels and aging, while few studies have investigated this relationship clinically. To fill this research gap, we determined the levels of major NMF components such as free amino acids, pyrrolidone carboxylic acid, and urocanic acids, and individually verified their relationships with skin hydration, barrier function, age, and skin aging. Purpose: The objective of this study was to clinically investigate the relationship between NMF components levels and skin aging in facial skin. The main NMF components were obtained from facial skin and quantified. We then selected NMF components showing strong relationships to skin hydration, and analyzed the relationships of the levels of these selected NMF components with signs of skin aging, namely, texture, pores, wrinkles, and dullness (L-value). We also examined the efficacy of treatment with a skin care formula (SK-II Facial Treatment Essence, called SK-II FTE hereafter) including Galactomyces ferment filtrate (GFF, PiteraTM) on the selected NMF component levels associated with skin hydration and barrier function, and the signs of skin aging of texture, pores, wrinkles, and dullness (L-value). Method: We conducted two clinical trials in this research. In Study 1, we measured 23 NMF components using tape-stripped cornified layer to quantify them via an HPLC method in 196 Asian females aged 20 to 59 (mean S.D., 38.6 9.4). Facial visual aging parameters [texture, pores, wrinkles, and dullness (L-value)], as well as elasticity (R7), skin hydration, and TEWL, were quantified using facial skin imaging and skin physical property measurement devices. Study 2 was performed to evaluate whether the facial application of SK-II FTE affects the NMF levels and skin aging parameters in 63 Asian female volunteers aged 20 to 55 (38.4 9.03). During the course of Study 2, 0.6 mL of SK-II FTE was applied to the face twice daily in the morning and afternoon. Skin measurements were performed at the start of the day (baseline) and at week 8. Results: In Study 1, we examined the stratum corneum levels of 23 NMF components comparing to the skin hydration status in 196 female subjects. The subjects were divided into two groups using the median of each measured NMF component. Skin hydration values were compared between the two groups defined for each NMF component. The results showed that subjects with higher levels of six amino acids, alanine, arginine, asparagine, glutamine, glycine, and histidine, exhibited significantly higher skin hydration than those with lower amino acid levels. No significant differences in skin hydration values were found for the other 17 NMF components. We then analyzed whether the sum of these six amino acid NMF components (called 6-AA-NMFs, hereafter) is affected by aging. The 6-AA-NMF level peaked in the subjects aged 25-29, and then gradually and significantly decreased with age. Interestingly, the 6-AA-NMF level was significantly correlated with the skin hydration value, but not with TEWL. In addition, the 6-AA-NMF level demonstrated significant correlations with the signs of skin aging of texture, pores, wrinkles, and dullness (L-value). Then, in Study 2, we examined whether the daily application of SK-II FTE affects the 6-AA-NMF level and visual aging parameters in 63 females. SK-II FTE demonstrated significant increases of the levels of 6-AA-NMFs and each of its components associated with hydration and barrier function, and improvements of skin texture, pores, wrinkles, and dullness (L-value) during the 8 weeks of treatment of facial skin. Conclusion: These clinical studies with large numbers of subjects across a wide age range revealed that six amino acids as NMF components were highly correlated with facial skin hydration in the stratum corneum. The levels of these six NMF components were also found to decrease at ages after the 30 s and were significantly correlated with major signs of skin aging. Notably, these six NMF components (6-AA-NMFs) were increased by SK-II FTE treatment associated with improvements of skin hydration and signs of skin aging, namely, texture, pores, wrinkles, and dullness (L-value). These studies were limited by the lack of investigation of why some NMF components were not associated with skin hydration. More clinical trials examining various NMF components and their relationship with aging are anticipated. 展开更多
关键词 NMF amino acid Visual Aging Parameter Hydration AGING Texture Pore Wrinkle Dullness Galactomyces Ferment Filtrate PiteraTM SK-II Facial Treatment Essence
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