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
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
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
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
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
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
There is a need to develop interventions to slow or reverse the degeneration of dopamine neurons in Parkinson’s disease after diagnosis.Given that preclinical and clinical studies suggest benefits of dietary n-3 poly...There is a need to develop interventions to slow or reverse the degeneration of dopamine neurons in Parkinson’s disease after diagnosis.Given that preclinical and clinical studies suggest benefits of dietary n-3 polyunsaturated fatty acids,such as docosahexaenoic acid,and exercise in Parkinson’s disease,we investigated whether both could synergistically interact to induce recovery of the dopaminergic pathway.First,mice received a unilateral stereotactic injection of 6-hydroxydopamine into the striatum to establish an animal model of nigrostriatal denervation.Four weeks after lesion,animals were fed a docosahexaenoic acid-enriched or a control diet for the next 8 weeks.During this period,the animals had access to a running wheel,which they could use or not.Docosahexaenoic acid treatment,voluntary exercise,or the combination of both had no effect on(i)distance traveled in the open field test,(ii)the percentage of contraversive rotations in the apomorphine-induction test or(iii)the number of tyrosine-hydroxylase-positive cells in the substantia nigra pars compacta.However,the docosahexaenoic acid diet increased the number of tyrosine-hydroxylase-positive terminals and induced a rise in dopamine concentrations in the lesioned striatum.Compared to docosahexaenoic acid treatment or exercise alone,the combination of docosahexaenoic acid and exercise(i)improved forelimb balance in the stepping test,(ii)decreased the striatal DOPAC/dopamine ratio and(iii)led to increased dopamine transporter levels in the lesioned striatum.The present results suggest that the combination of exercise and docosahexaenoic acid may act synergistically in the striatum of mice with a unilateral lesion of the dopaminergic system and provide support for clinical trials combining nutrition and physical exercise in the treatment of Parkinson’s disease.展开更多
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
Fatty acids are the main constituents of vegetable oils.To determine the fatty acid compositions of small trade vegetable oils and some less well studied beneficial vegetable oils,and investigate their relationships w...Fatty acids are the main constituents of vegetable oils.To determine the fatty acid compositions of small trade vegetable oils and some less well studied beneficial vegetable oils,and investigate their relationships with antioxidant activity and oxidative stability,gas chromatography-mass spectrometry was performed to characterize the associated fatty acid profiles.The antioxidant activity of vegetable oils,based on their DPPH-scavenging capacity(expressed as IC_(50) values),was used to assess their impact on human health,and their oxidative stability was characterized by performing lipid oxidation analysis to determine the oxidative induction time of fats and oils.In addition,correlation analyses were performed to examine associations between the fatty acid composition of the oils and DPPH-scavenging capacity and oxidative stability.The results revealed that among the assessed oils,coffee seed oil has the highest saturated fatty acid content(355.10 mg/g),whereas Garddenia jaminoides oil has the highest unsaturated fatty acid content(844.84 mg/g).Coffee seed oil was also found have the lowest DPPH IC_(50) value(2.30 mg/mL)and the longest oxidation induction time(17.09 h).Correlation analysis revealed a significant linear relationship(P<0.05)between oxidative stability and unsaturated fatty acid content,with lower contents tending to be associated with better oxidative stability.The findings of this study provide reference data for the screening of functional edible vegetable oils.展开更多
Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a collector.Flotation experiments showed that MFA produced a stronger in...Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a collector.Flotation experiments showed that MFA produced a stronger inhibition effect on pyrite than on chalcopyrite.The separation of chalcopyrite from pyrite was realized by introducing 150 mg/L MFA at a pulp pH of approximately 8.0.The copper grade,copper recovery,and separation efficiency were 28.03%,84.79%,and 71.66%,respectively.Surface adsorption tests,zeta potential determinations,and localized electrochemical impedance spectroscopy tests showed that more MFA adsorbed on pyrite than on chalcopyrite,which weakened the subsequent interactions between pyrite and the collector.Atomic force microscope imaging further confirmed the adsorption of MFA on pyrite,and X-ray photoelectron spectroscopy results indicated that hydrophilic Fe-based species on the pyrite surfaces increased after exposure of pyrite to MFA,thereby decreasing the floatability of pyrite.展开更多
Background Caffeic acid(CA)and its derivative,chlorogenic acid(CGA),have shown promise in preventing and alleviating fatty liver disease.CA,compared to CGA,has much lower production costs and higher bioavailability,ma...Background Caffeic acid(CA)and its derivative,chlorogenic acid(CGA),have shown promise in preventing and alleviating fatty liver disease.CA,compared to CGA,has much lower production costs and higher bioavailability,making it a potentially superior feed additive.However,the efficacy,mechanistic differences,and comparative impacts of CA and CGA on fatty liver disease in laying hens remain unclear.This study aimed to evaluate and compare the effects of CA and CGA on production performance,egg quality,and fatty liver disease in laying hens.Results A total of 1,44061-week-old Hyline Brown laying hens were randomly divided into 8 groups and fed diets supplemented with basal diet,25,50,100 and 200 mg/kg of CA,and 100,200 and 400 mg/kg of CGA(CON,CA25,CA50,CA100,CA200,CGA100,CGA200 and CGA400,respectively)for 12 weeks.Both CA and CGA improved production performance and egg quality,while reducing markers of hepatic damage and lipid accumulation.CA and CGA significantly decreased TG,TC,and LDL-C levels and increased T-SOD activity.Transcriptomic and proteomic analyses revealed that CA and CGA reduced hepatic lipid accumulation through downregulation of lipid biosynthesis-related genes(ACLY,ACACA,FASN,and SCD1)and enhanced lipid transport and oxidation genes(FABPs,CD36,CPT1A,ACOX1,and SCP2).Of note,low-dose CA25 exhibited equivalent efficacy to the higher dose CGA100 group in alleviating fatty liver conditions.Mechanistically,CA and CGA alleviated lipid accumulation via activation of the ADPN-AMPK-PPARαsignaling pathway.Conclusions This study demonstrates that dietary CA and CGA effectively improve laying performance,egg quality,and hepatic lipid metabolism in laying hens,with CA potentially being more economical and efficient.Transcriptomic and proteomic evidence highlight shared mechanisms between CA25 and CGA100.These findings provide a foundation for CA and CGA as therapeutic agents for fatty liver disease and related metabolic diseases in hens,and also offer insights into the targeted modification of CGA(including the isomer of CGA)into CA,thereby providing novel strategies for the efficient utilization of CGA.Highlights(1)Dietary CA and CGA improve fatty liver,laying performance and egg quality.(2)Lower dose of CA25 achieves the equivalent improvement as CGA100 or CGA200.(3)CA and CGA mediate the ADPN-AMPK-PPARαpathway to alleviate fatty liver.展开更多
Stroke,a major cerebrovascular disease,has high morbidity and mortality.Effective methods to reduce the risk and improve the prognosis are lacking.Currently,uric acid(UA)is associated with the pathological mechanism,p...Stroke,a major cerebrovascular disease,has high morbidity and mortality.Effective methods to reduce the risk and improve the prognosis are lacking.Currently,uric acid(UA)is associated with the pathological mechanism,prognosis,and therapy of stroke.UA plays pro/anti-oxidative and pro-inflammatory roles in vivo.The specific role of UA in stroke,which may have both neuroprotective and damaging effects,remains unclear.There is a U-shaped association between serum uric acid(SUA)levels and ischemic stroke(IS).UA therapy provides neuroprotection during reperfusion therapy for acute ischemic stroke(AIS).Urate-lowering therapy(ULT)plays a protective role in IS with hyperuricemia or gout.SUA levels are associated with the cerebrovascular injury mechanism,risk,and outcomes of hemorrhagic stroke.In this review,we summarize the current research on the role of UA in stroke,providing potential targets for its prediction and treatment.展开更多
Background Necrotic enteritis(NE)in broiler chickens leads to significant economic losses in poultry production.This study examined the inhibitory effects of usnic acid and tannic acid on coccidia,sporozoite,and Clost...Background Necrotic enteritis(NE)in broiler chickens leads to significant economic losses in poultry production.This study examined the inhibitory effects of usnic acid and tannic acid on coccidia,sporozoite,and Clostridium perfringens and assessed their influence on growth performance and intestinal health in NE-challenged broilers through in vitro and in vivo experiments.Methods The in vitro experiment included 5 treatment groups:the negative control(NC),2μmol/L diclazuril(DZ),30μmol/L usnic acid(UA),90μmol/L tannic acid(TA),and 15μmol/L usnic acid^(+)45μmol/L tannic acid(UTA)groups.The in vivo experiment involved 320 broilers divided into four groups:PC(NE-challenged),SA(500 mg/kg salinomycin premix^(+)NE-challenged),UA(300 mg/kg usnic acid^(+)NE-challenged),and UTA(300 mg/kg usnic acid^(+)500 mg/kg tannic acid^(+)NE-challenged)groups.Results In the in vitro study,the UA,TA,and UTA treatments significantly increased apoptosis in coccidian oocysts and sporozoites,lowered the mitochondrial membrane potential(P<0.05),and disrupted the oocyst structure compared with those in the NC group.UA and TA had inhibitory effects on C.perfringens,with the strongest inhibition observed in the UTA group.The in vivo results demonstrated that the SA group presented significantly improved growth performance on d 13,21,and 28(P<0.05),whereas the UA and UTA groups presented improvements on d 13 and 21(P<0.05).The SA,UA,and UTA treatments reduced the intestinal lesion scores by d 28 and the fecal coccidian oocyst counts from d 19 to 21(P<0.05).Compared with the PC group,the UA and UTA groups presented lower intestinal sIgA levels and CD8^(+)cell percentages(P<0.05),with a trend toward a reduced CD3^(+)cell percentage(P=0.069).The SA,UA,and UTA treatments significantly reduced the serum diamine oxidase activity,crypt depth,and plateletderived growth factor levels in the intestinal mucosa while increasing the villus height to crypt depth ratio and number of goblet cells(P<0.05).The UTA treatment also significantly increased the acetate and butyrate concentrations in the cecum(P<0.05).With respect to the gut microbiota,significant changes inβdiversity in the ileum and cecum were observed in the SA,UA,and UTA groups,indicating that the microbial community compositions differed among the groups.Romboutsia dominated the SA group,Bacillales dominated the UA group,and Lactobacillales and Lachnospirales dominated the UTA group in the ileal microbiota.In the cecal microbiota,Lactobacillus,Butyricicoccus,and Blautia abundances were significantly elevated in the UTA group(P<0.05).Conclusion Usnic acid and tannic acid induce apoptosis in coccidia and sporozoites by lowering the mitochondrial membrane potential.Both usnic acid alone and in combination with tannic acid alleviate NE-induced adverse effects in broilers by modulating intestinal immunity,altering the microbial composition,and improving intestinal barrier function.Compared with usnic acid alone,the combination of usnic acid and tannic acid had superior effects,providing a promising basis for the development of effective feed additive combinations.展开更多
High-capacity LiBH_(4)is a promising solid hydrogen storage material.However,the large electron cloud density between the B-H bonds in LiBH_(4)induces high dehydrogenation temperatures and sluggish dehydrogenation kin...High-capacity LiBH_(4)is a promising solid hydrogen storage material.However,the large electron cloud density between the B-H bonds in LiBH_(4)induces high dehydrogenation temperatures and sluggish dehydrogenation kinetics.To solve the above problems,it is proposed to enhance the hydrogen storage properties of LiBH_(4)through the synergistic effect of Brønsted and Lewis acid in Hβzeolite.Composite hydrogen storage systems with different mass ratios were prepared by simple ball-milling.At a LiBH_(4)-to-Hβmass ratio of 6:4,the 6LiBH_(4)-4Hβsystem released hydrogen at 190℃and achieved a hydrogen release capacity of 7.0 wt%H_(2)upon heating to 400℃.More importantly,the hydrogen release capacity of the system reached 6.02 wt%at 350℃under isothermal conditions after 100 min and 7.2 wt%at 400℃under isothermal conditions after 80 min,whereas the pristine LiBH_(4)only achieved 2.2 wt%.The improvement in hydrogen storage performance of the system was mainly attributed to two factors:(i)Lewis acid sites with acceptable electrons in the Hβweaken the electron density of B-H bonds in LiBH_(4),and(ii)the H+proton from the Brønsted acid sites and H−of LiBH_(4)undergo a H^(+)+H^(−)=H_(2)reaction.Theoretical calculations revealed that the Lewis and Brønsted acid sites in the Hβzeolite are conducive to the weakening of B-H bonds and that storage charge transfer occurs near the Lewis acid sites.The present work provides new insights into improving the hydrogen storage performance of LiBH_(4)by weakening the B-H bonds in the LiBH_(4).展开更多
The rare earth elements(REEs)extraction by chemical leaching from ion-adsorption type rare earth ores(IAREO)has led to serious ecological and environmental risks.Conversely,demand for bioleaching is on the rise with t...The rare earth elements(REEs)extraction by chemical leaching from ion-adsorption type rare earth ores(IAREO)has led to serious ecological and environmental risks.Conversely,demand for bioleaching is on the rise with the advantage of being environmental-friendly.As one of the organic acids produced by biological metabolism,citric acid was used to leach REEs and explore the performance and process.The results demonstrate that citric acid exhibits higher leaching efficiency(96.00%)for REEs at a relatively low concentration of 0.01 mol/L compared with(NH_(4))_(2)SO_(4)(84.29%,0.1 mol/L)and MgSO_(4)(83.99%,0.1 mol/L).Citric acid shows a preference for leaching heavy rare earth elements,with 99%leaching efficiency in IAREO,which shows higher capacity than(NH_(4))_(2)SO_(4)and MgSO_(4)(as inorganic leaching agents).Kinetic analysis indicates that the leaching process of REEs with citric acid is controlled by both the internal diffusion kinetics and chemical reaction kinetics,which is different from inorganic leaching agents.Visual Minteq calculations confirm that RE-Citrate is the main constituent of the extract solution in the leaching process of the IAREO,thereby enhancing the leaching efficiency of REEs from the IAREO.It suggests that citric acid may be used as a promising organic leaching agent for the environmentalfriendly extraction of REEs from IAREO.展开更多
BACKGROUND Lower salivary uric acid concentrations,the most abundant antioxidant agent in saliva,have been observed in patients with periodontitis compared to individuals with periodontal health.However,the independen...BACKGROUND Lower salivary uric acid concentrations,the most abundant antioxidant agent in saliva,have been observed in patients with periodontitis compared to individuals with periodontal health.However,the independent association of salivary uric acid levels with periodontitis,accounting for other risk factors,as well as its association with periodontitis severity,has not been investigated.AIM To the independent association of salivary uric acid levels with periodontitis and the association of salivary uric acid levels with the severity of periodontitis.METHODS This observational and prospective study measured salivary uric acid levels in subjects with periodontitis(characterized by periodontal loss of tissue)and in subjects without periodontitis(periodontal health or localized gingivitis in<30%of sites).Multivariate regression analysis was performed to determine independent factors associated with periodontitis.Spearman’s rho correlation coefficient was used to assess the relationship between salivary uric acid levels and periodontitis severity.A receiver operating characteristic analysis was carried out to evaluate the diagnostic performance of salivary uric acid levels in periodontitis,reporting the area under curve(AUC)and its 95%CI.RESULTS We included 121 subjects,61 of them with periodontitis and 60 without periodontitis(39 with periodontal health and 21 with local gingivitis).Subjects with periodontitis compared to those without periodontitis were older(P<0.001),had higher salivary uric acid levels(P=0.002),higher rate of arterial hypertension history(P=0.001)and higher rate of never-smoker history(P<0.001).The AUC for periodontitis diagnosis by salivary uric acid levels was 66%(95%CI:57%-75%;P<0.001)and the better cut-off point was 111 nmol/mL.Multiple logistic regression analysis showed an independent association of salivary uric acid levels<111 nmol/mL(OR=6.14;95%CI:2.015-18.721;P=0.001)with periodontitis after controlling for age,never-smoker history and arterial hypertension.A negative correlation of salivary uric acid levels and periodontitis severity was observed(rho=-0.32;P<0.001).CONCLUSION The two novel findings of our research were,first,that low salivary uric acid concentrations are independently associated with periodontitis,even after accounting for established risk factors.Second,salivary uric acid levels show a negative correlation with periodontitis severity.展开更多
The persistent stability of ruthenium dioxide(RuO_(2))in acidic oxygen evolution reactions(OER)is compromised by the involvement of lattice oxygen(LO)and metal dissolution during the OER process.Heteroatom doping has ...The persistent stability of ruthenium dioxide(RuO_(2))in acidic oxygen evolution reactions(OER)is compromised by the involvement of lattice oxygen(LO)and metal dissolution during the OER process.Heteroatom doping has been recognized as a viable strategy to foster the stability of RuO_(2)for acidic OER applications.This study presented an ion that does not readily gain or lose electrons,Ba^(2+),into RuO_(2)(Ba-RuO_(2))nanosheet(NS)catalyst that increased the number of exposed active sites,achieving a current density of 10 mA/cm^(2)with an overpotential of only 229 mV and sustaining this output for over 250 h.According to density functional theory(DFT)and X-ray absorption spectroscopy,Ba doping resulted in a longer Ru-O bond length,which in turn diminished the covalency of the bond.This alteration curtailed the involvement of LO and the dissolution of ruthenium(Ru),thereby markedly improving the durability of the catalyst over extended periods.Additionally,attenuated total reflectance-surface enhanced infrared absorption spectroscopy analysis substantiated that the OER mechanism shifted from a LO-mediated pathway to an adsorbate evolution pathway due to Ba doping,thereby circumventing Ru over-oxidation and further enhancing the stability of RuO_(2).Furthermore,DFT findings uncovered that Ba doping optimizes the adsorption energy of intermediates,thus enhancing the OER activity in acidic environments.This study offers a potent strategy to guide future developments on Ru-based oxide catalysts'stability in an acidic environment.展开更多
Polymeric materials which can undergo controlled degradation and recycling are of great significance for a sustainable society.Although tremendous progress has been made in the degradation and recycling of both thermo...Polymeric materials which can undergo controlled degradation and recycling are of great significance for a sustainable society.Although tremendous progress has been made in the degradation and recycling of both thermoplastic and thermoset plastics,the development of high-performance degradable polymer adhesives is rare.Here,we have prepared high-performance nucleobase-containing thioctic acid-based supramolecular polymer adhesives through free radical polymerization.The specific hydrogen-bonding interactions between complementary nucleobases greatly improve the weak cohesion of the thioctic acid-based polymers and enhance the environmental stability of the thioctic acidbased polymers simultaneously.Degradation of the nucleobase-containing thioctic acid-based supramolecular polymers is achieved by the reduction of the disulfide backbone,and the cycle of degradation and repolymerization is further achieved via oxidative polymerization.The adhesion strength of the nucleobase-containing thioctic acid-based supramolecular polymers after two cycles of degradation and repolymerization still reaches as high as 4.7±0.3 MPa.This work provides an approach for the development of environmentally stable and high-performance degradable thioctic acid-based adhesives.展开更多
Pyrrolizidine alkaloids(PAs)and their N-oxides(PANOs)are phytotoxins produced by various plant species and have been emerged as environmental pollutants.The sorption/desorption behaviors of PAs/PANOs in soil are cruci...Pyrrolizidine alkaloids(PAs)and their N-oxides(PANOs)are phytotoxins produced by various plant species and have been emerged as environmental pollutants.The sorption/desorption behaviors of PAs/PANOs in soil are crucial due to the horizontal transfer of these natural products from PA-producing plants to soil and subsequently absorbed by plant roots.This study firstly investigated the sorption/desorption behaviors of PAs/PANOs in tea plantation soils with distinct characteristics.Sorption amounts for seneciphylline(Sp)and seneciphylline-N-oxide(SpNO)in three acidic soils ranged from 2.9 to 5.9μg/g and 1.7 to 2.8μg/g,respectively.Desorption percentages for Sp and SpNO were from 22.2%to 30.5%and 36.1%to 43.9%.In the mixed PAs/PANOs systems,stronger sorption of PAs over PANOs was occurred in tested soils.Additionally,the Freundlich models more precisely described the sorption/desorption isotherms.Cation exchange capacity,sand content and total nitrogen were identified as major influencing factors by linear regression models.Overall,the soils exhibiting higher sorption capacities for compounds with greater hydrophobicity.PANOs were more likely to migrate within soils and be absorbed by tea plants.It contributes to the understanding of environmental fate of PAs/PANOs in tea plantations and provides basic data and clues for the development of PAs/PANOs reduction technology.展开更多
基金supported by the Hellenic Foundation for Research and Innovation,HFRI,“2nd Call for HFRI Research Projects to support Faculty Members&Researchers”Project 02667 to GL.
文摘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).
基金supported by the National Key R&D Program of China,No.2021YFC2501200(to PC).
文摘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.
基金Deutsche Forschungsgemeinschaft(DFG,German Research Foundation),project numbers 324633948 and 409784463(DFG grants Hi 678/9-3 and Hi 678/10-2,FOR2953)to HHBundesministerium für Bildung und Forschung-BMBF,project number 16LW0463K to HT.
文摘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.
基金supported by the Center for Cognition and Sociality,Institute for Basic Science(IBS)(IBS-R001-D2)(to WK).
文摘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.
基金supported by a grant from the French Society of Sleep Research and Medicine(to LS)The China Scholarship Council(to HL)The CNRS,INSERM,Claude Bernard University Lyon1(to LS)。
文摘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.
基金supported by MICIU(grant number PID2021-128133NB-100/AEI/FEDER10.13039/501100011033 to JMHG)by the National Institutes of Health(grant number R01 NS083858 to SAK)+1 种基金the Intramural Grants Program IGPP00057(to SAK)VIC enjoys a FPU contract from the Comunidad de Madrid(PIPF-2022/SAL-GL-25948)。
文摘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.
基金supported by funding from Parkinson Canadafunded by a scholarship from Parkinson Canadaa scholarship from Fonds d’Enseignement et de Recherche (FER) (Faculty of Pharmacy, Université Laval)
文摘There is a need to develop interventions to slow or reverse the degeneration of dopamine neurons in Parkinson’s disease after diagnosis.Given that preclinical and clinical studies suggest benefits of dietary n-3 polyunsaturated fatty acids,such as docosahexaenoic acid,and exercise in Parkinson’s disease,we investigated whether both could synergistically interact to induce recovery of the dopaminergic pathway.First,mice received a unilateral stereotactic injection of 6-hydroxydopamine into the striatum to establish an animal model of nigrostriatal denervation.Four weeks after lesion,animals were fed a docosahexaenoic acid-enriched or a control diet for the next 8 weeks.During this period,the animals had access to a running wheel,which they could use or not.Docosahexaenoic acid treatment,voluntary exercise,or the combination of both had no effect on(i)distance traveled in the open field test,(ii)the percentage of contraversive rotations in the apomorphine-induction test or(iii)the number of tyrosine-hydroxylase-positive cells in the substantia nigra pars compacta.However,the docosahexaenoic acid diet increased the number of tyrosine-hydroxylase-positive terminals and induced a rise in dopamine concentrations in the lesioned striatum.Compared to docosahexaenoic acid treatment or exercise alone,the combination of docosahexaenoic acid and exercise(i)improved forelimb balance in the stepping test,(ii)decreased the striatal DOPAC/dopamine ratio and(iii)led to increased dopamine transporter levels in the lesioned striatum.The present results suggest that the combination of exercise and docosahexaenoic acid may act synergistically in the striatum of mice with a unilateral lesion of the dopaminergic system and provide support for clinical trials combining nutrition and physical exercise in the treatment of Parkinson’s disease.
文摘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.
文摘Fatty acids are the main constituents of vegetable oils.To determine the fatty acid compositions of small trade vegetable oils and some less well studied beneficial vegetable oils,and investigate their relationships with antioxidant activity and oxidative stability,gas chromatography-mass spectrometry was performed to characterize the associated fatty acid profiles.The antioxidant activity of vegetable oils,based on their DPPH-scavenging capacity(expressed as IC_(50) values),was used to assess their impact on human health,and their oxidative stability was characterized by performing lipid oxidation analysis to determine the oxidative induction time of fats and oils.In addition,correlation analyses were performed to examine associations between the fatty acid composition of the oils and DPPH-scavenging capacity and oxidative stability.The results revealed that among the assessed oils,coffee seed oil has the highest saturated fatty acid content(355.10 mg/g),whereas Garddenia jaminoides oil has the highest unsaturated fatty acid content(844.84 mg/g).Coffee seed oil was also found have the lowest DPPH IC_(50) value(2.30 mg/mL)and the longest oxidation induction time(17.09 h).Correlation analysis revealed a significant linear relationship(P<0.05)between oxidative stability and unsaturated fatty acid content,with lower contents tending to be associated with better oxidative stability.The findings of this study provide reference data for the screening of functional edible vegetable oils.
基金supported by Fundamental Research Projects of Yunnan Province,China(Nos.202101BE070001-009,202301AU070189).
文摘Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a collector.Flotation experiments showed that MFA produced a stronger inhibition effect on pyrite than on chalcopyrite.The separation of chalcopyrite from pyrite was realized by introducing 150 mg/L MFA at a pulp pH of approximately 8.0.The copper grade,copper recovery,and separation efficiency were 28.03%,84.79%,and 71.66%,respectively.Surface adsorption tests,zeta potential determinations,and localized electrochemical impedance spectroscopy tests showed that more MFA adsorbed on pyrite than on chalcopyrite,which weakened the subsequent interactions between pyrite and the collector.Atomic force microscope imaging further confirmed the adsorption of MFA on pyrite,and X-ray photoelectron spectroscopy results indicated that hydrophilic Fe-based species on the pyrite surfaces increased after exposure of pyrite to MFA,thereby decreasing the floatability of pyrite.
基金supported by National Key R&D Program of China(2023YFD1301200)China Agriculture Research Systems(CARS-40-K11)+2 种基金Beijing Agriculture Innovation Consortium(BAIC06-2024-G05)Strategic Priority Research Program of the National Center of Technology Innovation for Pigs(NCTIP-XD/C08)The Chinese Academy of Agricultural Science and Technology Innovation Project(ASTIP-IAS-12)。
文摘Background Caffeic acid(CA)and its derivative,chlorogenic acid(CGA),have shown promise in preventing and alleviating fatty liver disease.CA,compared to CGA,has much lower production costs and higher bioavailability,making it a potentially superior feed additive.However,the efficacy,mechanistic differences,and comparative impacts of CA and CGA on fatty liver disease in laying hens remain unclear.This study aimed to evaluate and compare the effects of CA and CGA on production performance,egg quality,and fatty liver disease in laying hens.Results A total of 1,44061-week-old Hyline Brown laying hens were randomly divided into 8 groups and fed diets supplemented with basal diet,25,50,100 and 200 mg/kg of CA,and 100,200 and 400 mg/kg of CGA(CON,CA25,CA50,CA100,CA200,CGA100,CGA200 and CGA400,respectively)for 12 weeks.Both CA and CGA improved production performance and egg quality,while reducing markers of hepatic damage and lipid accumulation.CA and CGA significantly decreased TG,TC,and LDL-C levels and increased T-SOD activity.Transcriptomic and proteomic analyses revealed that CA and CGA reduced hepatic lipid accumulation through downregulation of lipid biosynthesis-related genes(ACLY,ACACA,FASN,and SCD1)and enhanced lipid transport and oxidation genes(FABPs,CD36,CPT1A,ACOX1,and SCP2).Of note,low-dose CA25 exhibited equivalent efficacy to the higher dose CGA100 group in alleviating fatty liver conditions.Mechanistically,CA and CGA alleviated lipid accumulation via activation of the ADPN-AMPK-PPARαsignaling pathway.Conclusions This study demonstrates that dietary CA and CGA effectively improve laying performance,egg quality,and hepatic lipid metabolism in laying hens,with CA potentially being more economical and efficient.Transcriptomic and proteomic evidence highlight shared mechanisms between CA25 and CGA100.These findings provide a foundation for CA and CGA as therapeutic agents for fatty liver disease and related metabolic diseases in hens,and also offer insights into the targeted modification of CGA(including the isomer of CGA)into CA,thereby providing novel strategies for the efficient utilization of CGA.Highlights(1)Dietary CA and CGA improve fatty liver,laying performance and egg quality.(2)Lower dose of CA25 achieves the equivalent improvement as CGA100 or CGA200.(3)CA and CGA mediate the ADPN-AMPK-PPARαpathway to alleviate fatty liver.
基金supported by the National Natural Science Foundation of China(82371300)Zhejiang Provincial Natural Science Foundation of China(LY23H090014)Zhejiang Province Traditional Chinese Medicine Science and Technology Project(2024ZL1215).
文摘Stroke,a major cerebrovascular disease,has high morbidity and mortality.Effective methods to reduce the risk and improve the prognosis are lacking.Currently,uric acid(UA)is associated with the pathological mechanism,prognosis,and therapy of stroke.UA plays pro/anti-oxidative and pro-inflammatory roles in vivo.The specific role of UA in stroke,which may have both neuroprotective and damaging effects,remains unclear.There is a U-shaped association between serum uric acid(SUA)levels and ischemic stroke(IS).UA therapy provides neuroprotection during reperfusion therapy for acute ischemic stroke(AIS).Urate-lowering therapy(ULT)plays a protective role in IS with hyperuricemia or gout.SUA levels are associated with the cerebrovascular injury mechanism,risk,and outcomes of hemorrhagic stroke.In this review,we summarize the current research on the role of UA in stroke,providing potential targets for its prediction and treatment.
基金supported by China Agriculture Research System Program(Project No.CARS-41-G04)。
文摘Background Necrotic enteritis(NE)in broiler chickens leads to significant economic losses in poultry production.This study examined the inhibitory effects of usnic acid and tannic acid on coccidia,sporozoite,and Clostridium perfringens and assessed their influence on growth performance and intestinal health in NE-challenged broilers through in vitro and in vivo experiments.Methods The in vitro experiment included 5 treatment groups:the negative control(NC),2μmol/L diclazuril(DZ),30μmol/L usnic acid(UA),90μmol/L tannic acid(TA),and 15μmol/L usnic acid^(+)45μmol/L tannic acid(UTA)groups.The in vivo experiment involved 320 broilers divided into four groups:PC(NE-challenged),SA(500 mg/kg salinomycin premix^(+)NE-challenged),UA(300 mg/kg usnic acid^(+)NE-challenged),and UTA(300 mg/kg usnic acid^(+)500 mg/kg tannic acid^(+)NE-challenged)groups.Results In the in vitro study,the UA,TA,and UTA treatments significantly increased apoptosis in coccidian oocysts and sporozoites,lowered the mitochondrial membrane potential(P<0.05),and disrupted the oocyst structure compared with those in the NC group.UA and TA had inhibitory effects on C.perfringens,with the strongest inhibition observed in the UTA group.The in vivo results demonstrated that the SA group presented significantly improved growth performance on d 13,21,and 28(P<0.05),whereas the UA and UTA groups presented improvements on d 13 and 21(P<0.05).The SA,UA,and UTA treatments reduced the intestinal lesion scores by d 28 and the fecal coccidian oocyst counts from d 19 to 21(P<0.05).Compared with the PC group,the UA and UTA groups presented lower intestinal sIgA levels and CD8^(+)cell percentages(P<0.05),with a trend toward a reduced CD3^(+)cell percentage(P=0.069).The SA,UA,and UTA treatments significantly reduced the serum diamine oxidase activity,crypt depth,and plateletderived growth factor levels in the intestinal mucosa while increasing the villus height to crypt depth ratio and number of goblet cells(P<0.05).The UTA treatment also significantly increased the acetate and butyrate concentrations in the cecum(P<0.05).With respect to the gut microbiota,significant changes inβdiversity in the ileum and cecum were observed in the SA,UA,and UTA groups,indicating that the microbial community compositions differed among the groups.Romboutsia dominated the SA group,Bacillales dominated the UA group,and Lactobacillales and Lachnospirales dominated the UTA group in the ileal microbiota.In the cecal microbiota,Lactobacillus,Butyricicoccus,and Blautia abundances were significantly elevated in the UTA group(P<0.05).Conclusion Usnic acid and tannic acid induce apoptosis in coccidia and sporozoites by lowering the mitochondrial membrane potential.Both usnic acid alone and in combination with tannic acid alleviate NE-induced adverse effects in broilers by modulating intestinal immunity,altering the microbial composition,and improving intestinal barrier function.Compared with usnic acid alone,the combination of usnic acid and tannic acid had superior effects,providing a promising basis for the development of effective feed additive combinations.
基金supported by the National Natural Science Foundation of China(No.52201274)the Project of Education Department of Shanxi Province(No.22JK0419).
文摘High-capacity LiBH_(4)is a promising solid hydrogen storage material.However,the large electron cloud density between the B-H bonds in LiBH_(4)induces high dehydrogenation temperatures and sluggish dehydrogenation kinetics.To solve the above problems,it is proposed to enhance the hydrogen storage properties of LiBH_(4)through the synergistic effect of Brønsted and Lewis acid in Hβzeolite.Composite hydrogen storage systems with different mass ratios were prepared by simple ball-milling.At a LiBH_(4)-to-Hβmass ratio of 6:4,the 6LiBH_(4)-4Hβsystem released hydrogen at 190℃and achieved a hydrogen release capacity of 7.0 wt%H_(2)upon heating to 400℃.More importantly,the hydrogen release capacity of the system reached 6.02 wt%at 350℃under isothermal conditions after 100 min and 7.2 wt%at 400℃under isothermal conditions after 80 min,whereas the pristine LiBH_(4)only achieved 2.2 wt%.The improvement in hydrogen storage performance of the system was mainly attributed to two factors:(i)Lewis acid sites with acceptable electrons in the Hβweaken the electron density of B-H bonds in LiBH_(4),and(ii)the H+proton from the Brønsted acid sites and H−of LiBH_(4)undergo a H^(+)+H^(−)=H_(2)reaction.Theoretical calculations revealed that the Lewis and Brønsted acid sites in the Hβzeolite are conducive to the weakening of B-H bonds and that storage charge transfer occurs near the Lewis acid sites.The present work provides new insights into improving the hydrogen storage performance of LiBH_(4)by weakening the B-H bonds in the LiBH_(4).
基金Project supported by the Thousand Talents Program of Jiangxi Province,China(JXSQ2023201003)National Natural Science Foundation of China(42107254)+4 种基金Science and Technology Major Program of Ordos City(2022EEDSKJZDZX014-2)Technological Innovation Guidance Program of Jiangxi Province(20212BDH81029)Rare Earth Industry Fund(IAGM2020DB06)Selfdeployed Projects of Ganjiang Innovation Academy,Chinese Academy of Sciences(E055A01)the Key Research Program of the Chinese Academy of Sciences(ZDRW-CN-2021-3-3)。
文摘The rare earth elements(REEs)extraction by chemical leaching from ion-adsorption type rare earth ores(IAREO)has led to serious ecological and environmental risks.Conversely,demand for bioleaching is on the rise with the advantage of being environmental-friendly.As one of the organic acids produced by biological metabolism,citric acid was used to leach REEs and explore the performance and process.The results demonstrate that citric acid exhibits higher leaching efficiency(96.00%)for REEs at a relatively low concentration of 0.01 mol/L compared with(NH_(4))_(2)SO_(4)(84.29%,0.1 mol/L)and MgSO_(4)(83.99%,0.1 mol/L).Citric acid shows a preference for leaching heavy rare earth elements,with 99%leaching efficiency in IAREO,which shows higher capacity than(NH_(4))_(2)SO_(4)and MgSO_(4)(as inorganic leaching agents).Kinetic analysis indicates that the leaching process of REEs with citric acid is controlled by both the internal diffusion kinetics and chemical reaction kinetics,which is different from inorganic leaching agents.Visual Minteq calculations confirm that RE-Citrate is the main constituent of the extract solution in the leaching process of the IAREO,thereby enhancing the leaching efficiency of REEs from the IAREO.It suggests that citric acid may be used as a promising organic leaching agent for the environmentalfriendly extraction of REEs from IAREO.
文摘BACKGROUND Lower salivary uric acid concentrations,the most abundant antioxidant agent in saliva,have been observed in patients with periodontitis compared to individuals with periodontal health.However,the independent association of salivary uric acid levels with periodontitis,accounting for other risk factors,as well as its association with periodontitis severity,has not been investigated.AIM To the independent association of salivary uric acid levels with periodontitis and the association of salivary uric acid levels with the severity of periodontitis.METHODS This observational and prospective study measured salivary uric acid levels in subjects with periodontitis(characterized by periodontal loss of tissue)and in subjects without periodontitis(periodontal health or localized gingivitis in<30%of sites).Multivariate regression analysis was performed to determine independent factors associated with periodontitis.Spearman’s rho correlation coefficient was used to assess the relationship between salivary uric acid levels and periodontitis severity.A receiver operating characteristic analysis was carried out to evaluate the diagnostic performance of salivary uric acid levels in periodontitis,reporting the area under curve(AUC)and its 95%CI.RESULTS We included 121 subjects,61 of them with periodontitis and 60 without periodontitis(39 with periodontal health and 21 with local gingivitis).Subjects with periodontitis compared to those without periodontitis were older(P<0.001),had higher salivary uric acid levels(P=0.002),higher rate of arterial hypertension history(P=0.001)and higher rate of never-smoker history(P<0.001).The AUC for periodontitis diagnosis by salivary uric acid levels was 66%(95%CI:57%-75%;P<0.001)and the better cut-off point was 111 nmol/mL.Multiple logistic regression analysis showed an independent association of salivary uric acid levels<111 nmol/mL(OR=6.14;95%CI:2.015-18.721;P=0.001)with periodontitis after controlling for age,never-smoker history and arterial hypertension.A negative correlation of salivary uric acid levels and periodontitis severity was observed(rho=-0.32;P<0.001).CONCLUSION The two novel findings of our research were,first,that low salivary uric acid concentrations are independently associated with periodontitis,even after accounting for established risk factors.Second,salivary uric acid levels show a negative correlation with periodontitis severity.
基金supported by Young Project of Education Department in Guizhou Province(No.2022099)the Natural Science Special of Guizhou University(No.X202220 Special Post A)the National Natural Science Foundation of China(Grant No.22208071)。
文摘The persistent stability of ruthenium dioxide(RuO_(2))in acidic oxygen evolution reactions(OER)is compromised by the involvement of lattice oxygen(LO)and metal dissolution during the OER process.Heteroatom doping has been recognized as a viable strategy to foster the stability of RuO_(2)for acidic OER applications.This study presented an ion that does not readily gain or lose electrons,Ba^(2+),into RuO_(2)(Ba-RuO_(2))nanosheet(NS)catalyst that increased the number of exposed active sites,achieving a current density of 10 mA/cm^(2)with an overpotential of only 229 mV and sustaining this output for over 250 h.According to density functional theory(DFT)and X-ray absorption spectroscopy,Ba doping resulted in a longer Ru-O bond length,which in turn diminished the covalency of the bond.This alteration curtailed the involvement of LO and the dissolution of ruthenium(Ru),thereby markedly improving the durability of the catalyst over extended periods.Additionally,attenuated total reflectance-surface enhanced infrared absorption spectroscopy analysis substantiated that the OER mechanism shifted from a LO-mediated pathway to an adsorbate evolution pathway due to Ba doping,thereby circumventing Ru over-oxidation and further enhancing the stability of RuO_(2).Furthermore,DFT findings uncovered that Ba doping optimizes the adsorption energy of intermediates,thus enhancing the OER activity in acidic environments.This study offers a potent strategy to guide future developments on Ru-based oxide catalysts'stability in an acidic environment.
基金supported by the National Natural Science Foundation of China(Nos.22273098,22373003,22103002 and 52033001)the Key Project of Anhui Province Science and Technology Innovation Platform(No.202305a12020030)the financial support from the Anhui Provincial Natural Science Foundation(No.2408085Y004)。
文摘Polymeric materials which can undergo controlled degradation and recycling are of great significance for a sustainable society.Although tremendous progress has been made in the degradation and recycling of both thermoplastic and thermoset plastics,the development of high-performance degradable polymer adhesives is rare.Here,we have prepared high-performance nucleobase-containing thioctic acid-based supramolecular polymer adhesives through free radical polymerization.The specific hydrogen-bonding interactions between complementary nucleobases greatly improve the weak cohesion of the thioctic acid-based polymers and enhance the environmental stability of the thioctic acidbased polymers simultaneously.Degradation of the nucleobase-containing thioctic acid-based supramolecular polymers is achieved by the reduction of the disulfide backbone,and the cycle of degradation and repolymerization is further achieved via oxidative polymerization.The adhesion strength of the nucleobase-containing thioctic acid-based supramolecular polymers after two cycles of degradation and repolymerization still reaches as high as 4.7±0.3 MPa.This work provides an approach for the development of environmentally stable and high-performance degradable thioctic acid-based adhesives.
基金supported by the earmarked fund for the Modern Agro-Industry Technology Research System (No.CARS-19)the Innovative Research Team in Chinese Academy of Agricultural Sciences (No.CAAS ASTIP-2014-TRICAAS).
文摘Pyrrolizidine alkaloids(PAs)and their N-oxides(PANOs)are phytotoxins produced by various plant species and have been emerged as environmental pollutants.The sorption/desorption behaviors of PAs/PANOs in soil are crucial due to the horizontal transfer of these natural products from PA-producing plants to soil and subsequently absorbed by plant roots.This study firstly investigated the sorption/desorption behaviors of PAs/PANOs in tea plantation soils with distinct characteristics.Sorption amounts for seneciphylline(Sp)and seneciphylline-N-oxide(SpNO)in three acidic soils ranged from 2.9 to 5.9μg/g and 1.7 to 2.8μg/g,respectively.Desorption percentages for Sp and SpNO were from 22.2%to 30.5%and 36.1%to 43.9%.In the mixed PAs/PANOs systems,stronger sorption of PAs over PANOs was occurred in tested soils.Additionally,the Freundlich models more precisely described the sorption/desorption isotherms.Cation exchange capacity,sand content and total nitrogen were identified as major influencing factors by linear regression models.Overall,the soils exhibiting higher sorption capacities for compounds with greater hydrophobicity.PANOs were more likely to migrate within soils and be absorbed by tea plants.It contributes to the understanding of environmental fate of PAs/PANOs in tea plantations and provides basic data and clues for the development of PAs/PANOs reduction technology.
