A Brønsted acid-catalyzed peroxidation of 3-hydroxyisoindolinones with hydroperoxides has been established for the first time,which constructsα-amino peroxides bearing a tetrasubstituted stereocenter in good to ...A Brønsted acid-catalyzed peroxidation of 3-hydroxyisoindolinones with hydroperoxides has been established for the first time,which constructsα-amino peroxides bearing a tetrasubstituted stereocenter in good to high yields and enantioselectivities.The transformation uses of environmentally benign solvents,and features operational simplicity,and high atom economy.The synthetic utility was demonstrated with the gram-scale reactions and further transformations of the products.Notably,preliminary bioactivity studies reveal that these valuableα-amino peroxides show potential anticancer activity.展开更多
Colorectal cancer(CRC), one of the leading causes of cancer-related mortality globally, urgently requires complementary and alternative therapies. Ferroptosis, an iron-dependent form of regulated cell death driven by ...Colorectal cancer(CRC), one of the leading causes of cancer-related mortality globally, urgently requires complementary and alternative therapies. Ferroptosis, an iron-dependent form of regulated cell death driven by lipid peroxidation, has emerged as a promising anticancer strategy. Dendrobium officinale(D. officinale), a renowned traditional Chinese medicinal herb, is widely used in several Asian countries for its nutritional and therapeutic benefits.Although D. officinale has demonstrated anti-tumor effects, the molecular mechanisms underlying its action against CRC remain incompletely characterized. This study aimed to elucidate the role of D. officinale in suppressing CRC through the induction of ferroptosis and its regulatory effects on glutathione peroxidase 4(GPX4), a key suppressor of ferroptosis. In vitro assays were conducted using HCT116 and SW480 CRC cell lines, and in vivo efficacy was evaluated in BALB/c nude mice bearing CRC xenografts. D. officinale significantly reduced CRC cell viability and proliferation in vitro and suppressed tumor growth in vivo. Induction of ferroptosis was evidenced by elevated levels of Fe^(2+), malondialdehyde(MDA), and lipid peroxidation, along with a depleted glutathione/oxidized glutathione disulfide(GSH/GSSG) ratio. Notably, these effects were reversed by ferroptosis inhibitors, including ferrostatin-1(Fer-1) and deferoxamine. Consistently, D. officinale markedly downregulated GPX4 expression. Overexpression of GPX4 rescued D. officinale-induced ferroptosis, whereas GPX4 silencing exacerbated this effect. D. officinale suppresses CRC by triggering GPX4-dependent ferroptosis,providing a novel, naturally derived therapeutic approach. These findings bridge traditional medicine and modern oncology, establishing a foundation for developing targeted CRC treatments.展开更多
Dynamic melt modification of polyethylene via the direct grafting of peroxide fragments shows promise for the development of processable functionalized materials.In this study,four linear low-density polyethylenes(LLD...Dynamic melt modification of polyethylene via the direct grafting of peroxide fragments shows promise for the development of processable functionalized materials.In this study,four linear low-density polyethylenes(LLDPEs)with comparable molecular weights but different short-chain branch(SCB)contents(ranging of 5-66 per 1000 carbon atoms)were modified via dynamic melt mixing using 2 wt% benzoyl peroxide at 145℃ and 50 r/min for 30 min.The influence of SCB content on the processability and structure of the resulting products was systematically investigated.All modified products exhibited good melt processability with melt flow rates(MFR)ranging from 0.46 g/10min to 1.07 g/10min.Products derived from low-SCB LLDPEs showed a lower MFR,higher cross-linking content,a larger number of long-chain branches,and a higher degree of benzoyl grafting.In contrast,those produced from high-SCB LLDPEs exhibited improved processability,reduced cross-linking,fewer long-chain branches,and lower benzoyl grafting levels.A detailed structural investigation of the soluble and insoluble fractions,which were separated using trichlorobenzene fractionation,was conducted to analyze the structural features of various modified products and demonstrate that the SCB content(i.e.,tertiary carbon density)significantly influences radical coupling during dynamic modification.Elevated tertiary carbon density,by introducing greater steric hindrance,suppresses radical coupling during dynamic modification,thereby reducing the efficiency of both crosslinking and peroxide fragment grafting.These findings provide new insights into the structure-reactivity relationships in peroxide-induced polyethylene modification and lay the foundation for tailoring material properties via dynamic processing.展开更多
The two-electron electrochemical oxygen reduction reaction(ORR)affords an appealing alternative for on-site production of hydrogen peroxide(H_(2)O_(2)),which can fulfill the demands of various applications even at low...The two-electron electrochemical oxygen reduction reaction(ORR)affords an appealing alternative for on-site production of hydrogen peroxide(H_(2)O_(2)),which can fulfill the demands of various applications even at low concentrations.Under neutral or near-neutral conditions,the electrolyte environment capable of electrochemically synthesizing H_(2)O_(2) exhibits diversity and holds vast potential for practical applications;however,the electrocatalytic performance is limited without desirable electrode materials.In this contribution,methoxylated nickel hydroxides were proposed for high-performance on-site H_(2)O_(2) electrosynthesis in different potassium fertilizer solutions.The methoxylation compared to pristine Ni(OH)_(2) was demonstrated to optimize the electronic structure with favorable adsorption of reaction intermediates,obviously enhancing the activity and selectivity.In 0.10 M K_(2)SO_(4) solution,H_(2)O_(2) production ranged from 28.1 to 153.6 mg h^(-1) cm^(-2) at current densities of-50 to-250 mA cm^(-2),accompanied by Faradaic efficiency values exceeding 88.0%.An integrated system was devised by combining fertilization,disinfection,and irrigation through the coupling of two-electron ORR with agricultural irrigation,utilizing nutrient solutions as the electrolyte for on-site H_(2)O_(2) electrosynthesis.These findings afford a promising avenue for the practical application of 2e-ORR in neutral environments.展开更多
Background:Cardiac fibrosis following myocardial infarction(MI)drives adverse ventricular remodeling and heart failure,with cardiac fibroblasts(CFs)playing a central role.Glutathione S-transferase mu 1(GSTM1)is an imp...Background:Cardiac fibrosis following myocardial infarction(MI)drives adverse ventricular remodeling and heart failure,with cardiac fibroblasts(CFs)playing a central role.Glutathione S-transferase mu 1(GSTM1)is an important member of the glutathione S-transferase(GSTs)family,which plays an important role in maintaining cell homeostasis and detoxification.This study investigated the role and mechanism of GSTM1 in post-MI fibrosis.Methods:Multi-omics approaches(proteomics/scRNA-seq)identified GSTM1 as a dysregulated target in post-MI fibroblasts.Using a murine coronary ligation model,we assessed GSTM1 dynamics via molecular profiling,such as Western blotting,immunofluorescence,and real-time quantitative polymerase chain reaction.Adeno-associated virus serotype 9(AAV9)-mediated cardiac-specific GSTM1 overexpression was achieved through systemic delivery.In vitro studies employed transforming growth factor-β(TGF-β)-stimulated primary fibroblasts with siRNA/plasmid interventions.Mechanistic insights were derived from transcriptomics and lipid peroxidation assays.Results:The expression of GSTM1 in mouse CFs after MI was significantly down-regulated at both transcriptional and protein levels.In human dilated cardiomyopathy(DCM)patients with severe heart failure,GSTM1 expression was decreased alongside aggravated fibrosis.Overexpression of GSTM1 in post-MI mice improved cardiac function,while significantly reducing infarct size and fibrosis compared with the control group.In vitro models demonstrated that GSTM1 markedly attenuated collagen secretion and activation of fibroblasts,as well as suppressed their proliferation and migration.Further studies revealed that GSTM1 overexpression significantly inhibited the generation of intracellular and mitochondrial reactive oxygen species(ROS)under pathological conditions,suggesting that GSTM1 exerts an antioxidative stress effect in post-infarction fibroblasts.Further investigation of molecular mechanisms indicated that GSTM1 may suppress the initiation and progression of fibrosis by modulating lipid metabolism and ferroptosis-related pathways.Overexpression of GSTM1 significantly reduced lipid peroxidation and free ferrous iron levels in fibroblasts and mitochondria,markedly decreased ferroptosis-related indicators,and alleviated oxidative lipid levels[such as 12-hydroxyeicosapentaenoic acid(HEPE)and 9-,10-dihydroxy octadecenoic acid(DHOME)]under fibrotic conditions.GSTM1 enhanced the phosphorylation of signal transducer and activator of transcription 3(STAT3),thereby upregulating the downstream expression of glutathione peroxidase 4(GPX4),reducing ROS production,and mitigating fibroblast activation and phenotypic transformation by inhibiting lipid peroxidation.Conclusions:This study identifies GSTM1 as a key inhibitor of fibroblast activation and cardiac fibrosis,highlighting its ability to target ferroptosis through redox regulation.AAV-mediated GSTM1 therapy demonstrates significant therapeutic potential for improving outcomes post-MI.展开更多
Hydrogen peroxide(H_(2)O_(2)),as a green oxidant,plays a vital role in various applications,including environmental remediation,disinfection,and chemical synthesis[1].The conventional anthraquinone process,despite its...Hydrogen peroxide(H_(2)O_(2)),as a green oxidant,plays a vital role in various applications,including environmental remediation,disinfection,and chemical synthesis[1].The conventional anthraquinone process,despite its industrial maturity and high yield,suffers from high energy consumption,carbon emissions,safety risks,and reliance on precious metals[2].Despite ongoing optimizations,a more sustainable alternative is urgently needed.The direct synthesis of hydrogen peroxide from water and oxygen has long been considered as an ideal alternative due to its theoretical 100%atom efficiency and environmental sustainability.展开更多
Alzheimer's disease is an age-related neurodegenerative disorder with a complex and incompletely understood pathogenesis. Despite extensive research, a cure for Alzheimer's disease has not yet been found. Oxid...Alzheimer's disease is an age-related neurodegenerative disorder with a complex and incompletely understood pathogenesis. Despite extensive research, a cure for Alzheimer's disease has not yet been found. Oxidative stress mediates excessive oxidative responses, and its involvement in Alzheimer's disease pathogenesis as a primary or secondary pathological event is widely accepted. As a member of the selenium-containing antioxidant enzyme family, glutathione peroxidase 4 reduces esterified phospholipid hydroperoxides to maintain cellular redox homeostasis. With the discovery of ferroptosis, the central role of glutathione peroxidase 4 in anti-lipid peroxidation in several diseases, including Alzheimer's disease, has received widespread attention. Increasing evidence suggests that glutathione peroxidase 4 expression is inhibited in the Alzheimer's disease brain, resulting in oxidative stress, inflammation, ferroptosis, and apoptosis, which are closely associated with pathological damage in Alzheimer's disease. Several therapeutic approaches, such as small molecule drugs, natural plant products, and non-pharmacological treatments, ameliorate pathological damage and cognitive function in Alzheimer's disease by promoting glutathione peroxidase 4 expression and enhancing glutathione peroxidase 4 activity. Therefore, glutathione peroxidase 4 upregulation may be a promising strategy for the treatment of Alzheimer's disease. This review provides an overview of the gene structure, biological functions, and regulatory mechanisms of glutathione peroxidase 4, a discussion on the important role of glutathione peroxidase 4 in pathological events closely related to Alzheimer's disease, and a summary of the advances in small-molecule drugs, natural plant products, and non-pharmacological therapies targeting glutathione peroxidase 4 for the treatment of Alzheimer's disease. Most prior studies on this subject used animal models, and relevant clinical studies are lacking. Future clinical trials are required to validate the therapeutic effects of strategies targeting glutathione peroxidase 4 in the treatment of Alzheimer's disease.展开更多
Ferroptosis,a type of programmed cell death,represents a distinct paradigm in cell biology.It is characterized by the iron-dependent accumulation of reactive oxygen species,which induce lipid peroxidation(LPO),and is ...Ferroptosis,a type of programmed cell death,represents a distinct paradigm in cell biology.It is characterized by the iron-dependent accumulation of reactive oxygen species,which induce lipid peroxidation(LPO),and is orchestrated by the interplay between iron,lipid peroxides,and glutathione.In this review,we emphasize the frequently overlooked role of iron in LPO beyond the classical iron-driven Fenton reaction in several crucial processes that regulate cellular iron homeostasis,including iron intake and export as well as ferritinophagy,and the emerging roles of endoplasmic reticulum-resident flavoprotein oxidoreductases,especially P450 oxidoreductases,in modulating LPO.We summarize how various types of fatty acids(FAs),including saturated,monounsaturated,and polyunsaturated FAs,differentially influence ferroptosis when incorporated into phospholipids.Furthermore,we highlight the therapeutic potential of targeting LPO to mitigate ferroptosis and discuss the regulatory mechanisms of endogenous lipophilic radical-trapping antioxidants that confer resistance to ferroptosis,shedding light on therapeutic avenues for ferroptosis-associated diseases.展开更多
BACKGROUND Fistula-in-ano is an abnormal tunnel formation linking the anal canal with the perineum and perianal skin.Multiple imagining methods are available to evaluate it,among which magnetic resonance imaging(MRI)i...BACKGROUND Fistula-in-ano is an abnormal tunnel formation linking the anal canal with the perineum and perianal skin.Multiple imagining methods are available to evaluate it,among which magnetic resonance imaging(MRI)is the most advanced nonin-vasive preoperative method.However,it is limited in its visualization function.AIM To investigate the use of intraluminal MRI for perianal fistulas via a novel direct MRI fistulography method.METHODS We mixed 3%hydrogen peroxide(HP)with gadolinium for HPMRI fistulogra-phy,retrospectively analyzing 60 cases of complex/recurrent fistula-in-ano using physical examination,trans-perineal ultrasonography(TPUS),low-spatial-reso-lution MRI,and high-resolution direct HPMRI fistulography.We assessed detec-tion rates of fistula tracks,internal openings,their relationship with anal sphinc-ters,and perianal abscesses using statistical analyses,including interobserver agreement(Kappa statistic),and compared results with intraoperative findings.RESULTS Surgical confirmation in 60 cases showed that high-resolution direct HPMRI fis-tulography provided superior detection rates for internal openings(153)and fistula tracks(162)compared to physical exams,TPUS,and low-spatial-resolution MRI(Z>5.7,P<0.05).The effectiveness of physical examination and TPUS was also inferior to that of our method for detecting perianal abscesses(54)(Z=6.773,3.694,P<0.05),whereas that of low-spatial-resolution MRI was not significantly different(Z=1.851,P=0.06).High-resolution direct HPMRI fistulography also achieved the highest interobserver agreement(Kappa:0.89,0.85,and 0.80),while low-spatial-resolution MRI showed moderate agreement(Kappa:0.78,0.74,and 0.69).TPUS and physical examination had lower agreement(Kappa range:0.33-0.63).CONCLUSION High-resolution direct HPMRI fistulography enhances the visualization of recurrent and complex fistula-in-ano,including branched fistulas,allowing for precise planning and improved surgical outcomes.展开更多
Selective electrocatalysis of two-electron oxygen reduction reaction(2e^(-)ORR)has been recognized as a sustainable and on-site process for hydrogen peroxide(H_(2)O_(2))production.Great progress has been achieved for ...Selective electrocatalysis of two-electron oxygen reduction reaction(2e^(-)ORR)has been recognized as a sustainable and on-site process for hydrogen peroxide(H_(2)O_(2))production.Great progress has been achieved for 2e^(-)ORR in alkaline media.However,it is challenged by insufficient activity and selectiv-ity of the catalysts in acidic electrolytes.Herein,we report sulfur-poisoned PtNi/C catalysts(PtNiSx/C)that could regulate ORR from the 4e^(-)to 2e^(-)pathway.The identified PtNiS0.6/C offers high activity in terms of onset potential of∼0.69 V(vs.RHE)and∼80%selectivity.The mass activity is also compara-ble and outperforms representative Pt-based precious and transition-metal-based catalysts.In addition,it is interestingly found that the Faradaic efficiency further increased to 95%during the long-term elec-trolysis test due to Ni atom surface migration.The electrochemical production of the H_(2)O_(2)system was applied to the electro-Fenton process,which has realized the effective degradation of organic pollutants.This work offers a strategy by sulfur poisoning PtNi/C catalyst to realize Pt-based 2e^(-)ORR active catalysts to electrolysis of H_(2)O_(2)in acidic media.展开更多
Hydrogen peroxide(H_(2)O_(2))is a crucial,eco-friendly oxidizing agent with a wide range of industrial,environmental,and biomedical applications.Traditional production methods,such as the anthraquinone process,face si...Hydrogen peroxide(H_(2)O_(2))is a crucial,eco-friendly oxidizing agent with a wide range of industrial,environmental,and biomedical applications.Traditional production methods,such as the anthraquinone process,face significant challenges in terms of energy consumption and environmental impact.As a sustainable alternative,photocatalytic H_(2)O_(2) production,driven by solar energy,has emerged as a promising approach.This review discusses the key advancements in photocatalytic H_(2)O_(2) synthesis,focusing on overcoming challenges such as charge recombination,selectivity for the two-electron oxygen reduction reaction(2e^(-)ORR),and catalyst stability.Recent innovations in photocatalyst design,including high-entropy materials,single-atom catalysts,and covalent organic frameworks(COFs),have significantly enhanced efficiency and stability.Furthermore,novel strategies for optimizing charge separation,light harvesting,and mass transfer are explored.The integration of artificial intelligence and bioinspired systems holds potential for accelerating progress in this field.This review provides a comprehensive overview of current challenges and cutting-edge solutions,offering valuable insights for the development of scalable,decentralized H_(2)O_(2) production systems that contribute to a more sustainable future.展开更多
[Objective] The aim of this study was to investigate the characteristics and mechanism of chemical emasculation in rapeseed and to provide the theoretical basis for development and utilization of new chemical gametoci...[Objective] The aim of this study was to investigate the characteristics and mechanism of chemical emasculation in rapeseed and to provide the theoretical basis for development and utilization of new chemical gametocides.[Method] The activity of peroxidase,catalase and the content of hydrogen peroxide,malondialdehyde in leaves and flower buds of Brassica napus cultivars Qinyou No.3 and L89 induced by the chemical gametocide EXP in the course of male sterility were studied.[Result] Protective enzyme activity and the content of hydrogen peroxide,malondialdehyde in rapeseed treated with EXP changed significantly,which indicated that active oxygen metabolism was abnormal.Furthermore,there was a significant difference in the reaction degree of different cultivars and organs treated by EXP.[Conclusion] There was a correlation between the disturbance of active oxygen metabolism and the male sterility induced by chemical gametocide EXP.展开更多
A mesocosm-based study was conducted to assess the effect of glucose and hydrogen peroxide on periphyton communities. These chemicals have been found to be effective at controlling cyanobacteria blooms in the water co...A mesocosm-based study was conducted to assess the effect of glucose and hydrogen peroxide on periphyton communities. These chemicals have been found to be effective at controlling cyanobacteria blooms in the water column but their impact on attached communities is unknown. The experimental design included a total of 4 treatments: control (no chemicals;3 replicates);hydrogen peroxide (3 replicates);glucose alone (3 different concentrations [no replicates]);and additive glucose (3 replicates). After 34 days, mean values of chlorophyll a were lower in all experimental treatments compared to the control;mean AFDM values were lower in all treatments except the unreplicated high glucose alone treatment. In contrast, mean autotrophic index values (AFDM/chlorophyll a) were greater in all treatments compared to the control, indicating heterotrophs were more resistant to the chemical treatments than autotrophs. Periphyton community biodiversity was much lower in the additive glucose and moderate glucose alone treatments than the hydrogen peroxide and control treatments. The relative abundance of the bacteria Asticcacaulis and Sphingorhabdus responded positively to the glucose treatments, whereas relative abundance of Nevskia and Caenimonas declined in both the hydrogen peroxide and glucose treatments. In terms of relative abundance, no cyanobacteria taxa were detected among the top 20 taxa. We conclude that the autotrophic component of periphyton communities is especially vulnerable to hydrogen peroxide and glucose treatments, and that any management strategy employing these chemicals should be aware of this potential impact.展开更多
Pyrrhotite oxidation poses a big threat to water environment duo to its high potential for generating pollutants.Hydrogen peroxide,commonly found in natural water at micromolar concentrations,possesses much more aggre...Pyrrhotite oxidation poses a big threat to water environment duo to its high potential for generating pollutants.Hydrogen peroxide,commonly found in natural water at micromolar concentrations,possesses much more aggressive oxidation ability than oxygen and can complicate the pyrrhotite oxidation process.Here,the effects of micromolar H_(2)O_(2) on the biotic and abiotic oxidation of pyrrhotite were examined at pH 1.93 and 6.45,respectively.Pyrrhotite oxidation was much more severe in acidic solutions compared to near neutral solutions.Jarosite with a high Fe/S molar ratio was widely detected in the precipitate collected in acidic solutions,and the introduction of external H_(2)O_(2) influenced the crystallinity of jarosite.A layer of iron-deficient iron-sulfur oxide formed on the surface of pyrrhotite prevents its continuous oxidation,and the presence of Acidithiobacillus ferrooxidans enhanced this situation by promoting the release of Fe from the pyrrhotite.Additionally,the presence of external micromolar H_(2)O_(2) also determined the elemental state on pyrrhotite surface,as it found that the contribution of Fe^(3+)and S(S^(4+)and S^(6+))species on pyrrhotite surface increased with the increase of H_(2)O_(2) concentration in the solutions,especially in the presence of Acidithiobacillus ferrooxidans.展开更多
This letter addresses Pravda's innovative review,which proposes hydrogen pe-roxide as the primary pathogenic factor in ulcerative colitis(UC).Although the author presents intriguing mechanistic insights and report...This letter addresses Pravda's innovative review,which proposes hydrogen pe-roxide as the primary pathogenic factor in ulcerative colitis(UC).Although the author presents intriguing mechanistic insights and reports encouraging clinical outcomes with reducing agents,several methodological and clinical considera-tions require discussion.We examine three key aspects:The selective evidence synthesis approach;the need for rigorous clinical validation of proposed thera-pies;and the integration of this novel hypothesis with established inflammatory bowel disease pathogenesis.Given the complexity of UC,future therapeutic ad-vances may require collaborative approaches that integrate redox-based mecha-nisms into existing evidence-based frameworks rather than replacing current paradigms.展开更多
The photocatalytic hydrogen peroxide(H_(2)O_(2))production by graphitic carbon nitride is a sustainable and environment-benign alternative approach of conventional anthraquinone autoxidation technology,but it is great...The photocatalytic hydrogen peroxide(H_(2)O_(2))production by graphitic carbon nitride is a sustainable and environment-benign alternative approach of conventional anthraquinone autoxidation technology,but it is great challenges to promote two-electron O_(2)reduction and water oxidation.Herein,we present the well-dispersed graphitic carbon nitride quantum dots decorated with cyano groups(Na-CNQD and K-CNQD)by thermal polymerization of melamine in the presence of metal fluoride.The quantum confinement and edge effect have endowed the photocatalysts with rich active sites,wide light absorption range and the inhibited charge recombination.The cyano moieties function as O_(2)reduction centers to accept the photogenerated electrons and facilitate their rapid transfer to O_(2)molecules.This process enables the selective two-electron reduction of O_(2),leading to the production of H_(2)O_(2).Concurrently,the valence band holes on the heptazine moiety oxidize water into H_(2)O_(2).These synergistic effects promote photocatalytic H_(2)O_(2)production from O_(2)and H_(2)O without the need for additional photosensitizers,organic scavengers and co-catalysts.In contrast,pristine carbon nitride nanosheets remain inactive under the same conditions.This study offers new strategies for rational design of carbon-based materials for solar-to-chemical energy conversion.展开更多
Ferroptosis is a new regulated cell death process executed by lipid peroxidation(LPO)of polyunsaturated fatty acids.Lipid droplets(LDs),as an important organelle for lipid storage and metabolism,are probably a major s...Ferroptosis is a new regulated cell death process executed by lipid peroxidation(LPO)of polyunsaturated fatty acids.Lipid droplets(LDs),as an important organelle for lipid storage and metabolism,are probably a major site of LPO and play critical roles in the regulation of ferroptosis.However,the detailed study on LPO in LDs has not been carried out because of the lack of LD-targeting tools for the in situ monitoring of LPO.Herein,the first LD-targeting LPO fluorescence probe(LD-LPO)has been developed.LD-LPO exhibits a rapid and selective fluorescence enhancement at 518 nm,which is unaffected by highly destructive reactive oxygen species(e.g.,hydroxyl radical)and environmental factor changes(e.g.,polarity and viscosity).LD-LPO is capable of targeting LDs and visualizing LPO within LDs in situ during erastin-or(1S,3R)-RSL3(RSL3)-induced ferroptosis.Moreover,LD-LPO has also been used to image LPO in the ferroptosis-associated non-alcoholic fatty liver disease(NAFLD),and to evaluate the medicine treatment of NAFLD with saroglitazar,demonstrating its utility for monitoring LPO levels in biosystems.The favorable analytical and imaging performance of LD-LPO may allow its application in more ferroptosisassociated physiological and pathological processes.展开更多
Enhancing rubber-bitumen compatibility is crucial to improve pavement performance and durability.To investigate the compatibility improvement between H2O2-activated waste crumb rubber(AWCR)and bitumen,coarse and fine ...Enhancing rubber-bitumen compatibility is crucial to improve pavement performance and durability.To investigate the compatibility improvement between H2O2-activated waste crumb rubber(AWCR)and bitumen,coarse and fine waste crumb rubber(WCR)were treated and analyzed through multi-scale characterization and molecular simulation.Microstructure and chemical changes of WCR and AWCR were analyzed with scanning electron microscope(SEM),contact angle tests and Fourier transform infrared spectroscopy(FTIR).Compatibility was also indirectly evaluated through modified boiling tests and storage stability tests.Besides,molecular dynamics was used to explore the interaction between WCR/AWCR and bitumen.SEM,contact angle,and FTIR results showed bond breakage of C=C and C–C and increased polar groups like–OH and–COOH in AWCR,resulting in a rougher texture and higher surface energy.Compared with WCR,AWCR showed a lower bitumen stripping rate after boiling,and the binder with AWCR also had a lower softening point difference and segregation rate after storage.Molecular dynamics simulations further confirmed that AWCR has a closer solubility parameter and higher binding energy to bitumen than WCR,reflected in a relatively slower diffusion rate.This study provides comprehensive evidence for an eco-friendly method of WCR surface treatment for more efficient recycling of tire rubber in asphalt pavements.展开更多
Photocatalytic H_(2)O_(2) production still confronts the challenges of its dependence on organic electron donors or high-purity O_(2),which restricts the practical application,and there are few studies on the photo sy...Photocatalytic H_(2)O_(2) production still confronts the challenges of its dependence on organic electron donors or high-purity O_(2),which restricts the practical application,and there are few studies on the photo synthesis of H_(2)O_(2) via both oxygen reduction reaction(ORR)and water oxidation reaction(WOR).In this paper,bismuth yttrium oxyhalides Bi_(2)YO_(4)X(X=Cl,Br,or I)are demonstrated to afford sufficient driving forces to produce H_(2)O_(2) in the absence of sacrificial reagents.After modification with Pt and IrO_(2) as cocatalysts,which can selectively promote both ORR and WOR reactions on Bi_(2)YO_(4)Cl,the IrO_(2)-Pt/Bi_(2)YO_(4)Cl sample yields H_(2)O_(2) production activity of 647μmol L^(-1)h^(-1)with negligible decay in the long-term reaction using only H_(2)O and an air atmosphere as the electron donors and O_(2) source.Detailed characterizations reveal that the ORR reaction obeys a two-electron pathway.We present the first example of oxyhalides(Bi_(2)YO_(4)X)capable of efficient photocata lytic H_2O_(2) generation with record-breaking activity.展开更多
As a versatile and environmentally benign oxidant,hydrogen peroxide(H_(2)O_(2))is highly desired in sanitation,disinfection,environmental remediation,and the chemical industry.Compared with the conventional anthraquin...As a versatile and environmentally benign oxidant,hydrogen peroxide(H_(2)O_(2))is highly desired in sanitation,disinfection,environmental remediation,and the chemical industry.Compared with the conventional anthraquinone process,the electrosynthesis of H_(2)O_(2)through the two-electron oxygen reduction reaction(2e^(−)ORR)is an efficient,competitive,and promising avenue.Electrocatalysts and devices are two core factors in 2e^(−)ORR,but the design principles of catalysts for different pH conditions and the development trends of relevant synthesis devices remain unclear.To this end,this review adopts a multiscale perspective to summarize recent advancements in the design principles,catalytic mechanisms,and application prospects of 2e^(−)ORR catalysts,with a particular focus on the influence of pH conditions,aiming at providing guidance for the selective design of advanced 2e^(−)ORR catalysts for highly-efficient H_(2)O_(2)production.Moreover,in response to diverse on-site application demands,we elaborate on the evolution of H_(2)O_(2)electrosynthesis devices,from rotating ring-disk electrodes and H-type cells to diverse flow-type cells.We elaborate on their characteristics and shortcomings,which can be beneficial for their further upgrades and customized applications.These insights may inspire the rational design of innovative catalysts and devices with high performance and wide serviceability for large-scale implementations.展开更多
基金supported by the National Natural Science Foundation of China(No.52173044)we thank Dr.Fengchao Wang(Instrumental Analysis and Research Center,Tianjin University of Traditional Chinese Medicine)for providing biological activity testing.
文摘A Brønsted acid-catalyzed peroxidation of 3-hydroxyisoindolinones with hydroperoxides has been established for the first time,which constructsα-amino peroxides bearing a tetrasubstituted stereocenter in good to high yields and enantioselectivities.The transformation uses of environmentally benign solvents,and features operational simplicity,and high atom economy.The synthetic utility was demonstrated with the gram-scale reactions and further transformations of the products.Notably,preliminary bioactivity studies reveal that these valuableα-amino peroxides show potential anticancer activity.
基金supported by the Department of Education of Guangdong Province (No.2023KTSCX024)the Project of Traditional Chinese Medicine Bureau of Guangdong Province(No.20251091)+3 种基金the Joint Funds of the National Natural Science Foundation of China (No.U22A20368)the Key-Area Research and Development Program of Guangdong Province (No.2020B1111100004)Guangdong Basic and Applied Basic Research Foundation (No.2020B1515130005)Shenzhen Baoan District Science and Technology Innovation Bureau Project(Nos.2022JD226 and 2023JD252)。
文摘Colorectal cancer(CRC), one of the leading causes of cancer-related mortality globally, urgently requires complementary and alternative therapies. Ferroptosis, an iron-dependent form of regulated cell death driven by lipid peroxidation, has emerged as a promising anticancer strategy. Dendrobium officinale(D. officinale), a renowned traditional Chinese medicinal herb, is widely used in several Asian countries for its nutritional and therapeutic benefits.Although D. officinale has demonstrated anti-tumor effects, the molecular mechanisms underlying its action against CRC remain incompletely characterized. This study aimed to elucidate the role of D. officinale in suppressing CRC through the induction of ferroptosis and its regulatory effects on glutathione peroxidase 4(GPX4), a key suppressor of ferroptosis. In vitro assays were conducted using HCT116 and SW480 CRC cell lines, and in vivo efficacy was evaluated in BALB/c nude mice bearing CRC xenografts. D. officinale significantly reduced CRC cell viability and proliferation in vitro and suppressed tumor growth in vivo. Induction of ferroptosis was evidenced by elevated levels of Fe^(2+), malondialdehyde(MDA), and lipid peroxidation, along with a depleted glutathione/oxidized glutathione disulfide(GSH/GSSG) ratio. Notably, these effects were reversed by ferroptosis inhibitors, including ferrostatin-1(Fer-1) and deferoxamine. Consistently, D. officinale markedly downregulated GPX4 expression. Overexpression of GPX4 rescued D. officinale-induced ferroptosis, whereas GPX4 silencing exacerbated this effect. D. officinale suppresses CRC by triggering GPX4-dependent ferroptosis,providing a novel, naturally derived therapeutic approach. These findings bridge traditional medicine and modern oncology, establishing a foundation for developing targeted CRC treatments.
基金financially supported by the Science and Technology Project of PetroChina Company Limited,China(No.2022DJ6314)the National Natural Science Foundation of China(No.52173056)。
文摘Dynamic melt modification of polyethylene via the direct grafting of peroxide fragments shows promise for the development of processable functionalized materials.In this study,four linear low-density polyethylenes(LLDPEs)with comparable molecular weights but different short-chain branch(SCB)contents(ranging of 5-66 per 1000 carbon atoms)were modified via dynamic melt mixing using 2 wt% benzoyl peroxide at 145℃ and 50 r/min for 30 min.The influence of SCB content on the processability and structure of the resulting products was systematically investigated.All modified products exhibited good melt processability with melt flow rates(MFR)ranging from 0.46 g/10min to 1.07 g/10min.Products derived from low-SCB LLDPEs showed a lower MFR,higher cross-linking content,a larger number of long-chain branches,and a higher degree of benzoyl grafting.In contrast,those produced from high-SCB LLDPEs exhibited improved processability,reduced cross-linking,fewer long-chain branches,and lower benzoyl grafting levels.A detailed structural investigation of the soluble and insoluble fractions,which were separated using trichlorobenzene fractionation,was conducted to analyze the structural features of various modified products and demonstrate that the SCB content(i.e.,tertiary carbon density)significantly influences radical coupling during dynamic modification.Elevated tertiary carbon density,by introducing greater steric hindrance,suppresses radical coupling during dynamic modification,thereby reducing the efficiency of both crosslinking and peroxide fragment grafting.These findings provide new insights into the structure-reactivity relationships in peroxide-induced polyethylene modification and lay the foundation for tailoring material properties via dynamic processing.
基金the support from the National Natural Science Foundation of China(22478221)China Postdoctoral Science Foundation(2023M741920 and GZC20231259)+1 种基金Huaneng Group Science and Technology Research Project(HNKJ23-H71)Department of Chemical Engineering-iBHE Cooperation Joint Fund Project(DCE-iBHE-2025-3)。
文摘The two-electron electrochemical oxygen reduction reaction(ORR)affords an appealing alternative for on-site production of hydrogen peroxide(H_(2)O_(2)),which can fulfill the demands of various applications even at low concentrations.Under neutral or near-neutral conditions,the electrolyte environment capable of electrochemically synthesizing H_(2)O_(2) exhibits diversity and holds vast potential for practical applications;however,the electrocatalytic performance is limited without desirable electrode materials.In this contribution,methoxylated nickel hydroxides were proposed for high-performance on-site H_(2)O_(2) electrosynthesis in different potassium fertilizer solutions.The methoxylation compared to pristine Ni(OH)_(2) was demonstrated to optimize the electronic structure with favorable adsorption of reaction intermediates,obviously enhancing the activity and selectivity.In 0.10 M K_(2)SO_(4) solution,H_(2)O_(2) production ranged from 28.1 to 153.6 mg h^(-1) cm^(-2) at current densities of-50 to-250 mA cm^(-2),accompanied by Faradaic efficiency values exceeding 88.0%.An integrated system was devised by combining fertilization,disinfection,and irrigation through the coupling of two-electron ORR with agricultural irrigation,utilizing nutrient solutions as the electrolyte for on-site H_(2)O_(2) electrosynthesis.These findings afford a promising avenue for the practical application of 2e-ORR in neutral environments.
基金supported by the National Natural Science Foundation of China(82270386,82070252,and 8207025)the Zhejiang Provincial Medical and Health Science and Technology Plan(2023RC020)the Zhejiang Provincial Natural Science Foundation(LR21H020001).
文摘Background:Cardiac fibrosis following myocardial infarction(MI)drives adverse ventricular remodeling and heart failure,with cardiac fibroblasts(CFs)playing a central role.Glutathione S-transferase mu 1(GSTM1)is an important member of the glutathione S-transferase(GSTs)family,which plays an important role in maintaining cell homeostasis and detoxification.This study investigated the role and mechanism of GSTM1 in post-MI fibrosis.Methods:Multi-omics approaches(proteomics/scRNA-seq)identified GSTM1 as a dysregulated target in post-MI fibroblasts.Using a murine coronary ligation model,we assessed GSTM1 dynamics via molecular profiling,such as Western blotting,immunofluorescence,and real-time quantitative polymerase chain reaction.Adeno-associated virus serotype 9(AAV9)-mediated cardiac-specific GSTM1 overexpression was achieved through systemic delivery.In vitro studies employed transforming growth factor-β(TGF-β)-stimulated primary fibroblasts with siRNA/plasmid interventions.Mechanistic insights were derived from transcriptomics and lipid peroxidation assays.Results:The expression of GSTM1 in mouse CFs after MI was significantly down-regulated at both transcriptional and protein levels.In human dilated cardiomyopathy(DCM)patients with severe heart failure,GSTM1 expression was decreased alongside aggravated fibrosis.Overexpression of GSTM1 in post-MI mice improved cardiac function,while significantly reducing infarct size and fibrosis compared with the control group.In vitro models demonstrated that GSTM1 markedly attenuated collagen secretion and activation of fibroblasts,as well as suppressed their proliferation and migration.Further studies revealed that GSTM1 overexpression significantly inhibited the generation of intracellular and mitochondrial reactive oxygen species(ROS)under pathological conditions,suggesting that GSTM1 exerts an antioxidative stress effect in post-infarction fibroblasts.Further investigation of molecular mechanisms indicated that GSTM1 may suppress the initiation and progression of fibrosis by modulating lipid metabolism and ferroptosis-related pathways.Overexpression of GSTM1 significantly reduced lipid peroxidation and free ferrous iron levels in fibroblasts and mitochondria,markedly decreased ferroptosis-related indicators,and alleviated oxidative lipid levels[such as 12-hydroxyeicosapentaenoic acid(HEPE)and 9-,10-dihydroxy octadecenoic acid(DHOME)]under fibrotic conditions.GSTM1 enhanced the phosphorylation of signal transducer and activator of transcription 3(STAT3),thereby upregulating the downstream expression of glutathione peroxidase 4(GPX4),reducing ROS production,and mitigating fibroblast activation and phenotypic transformation by inhibiting lipid peroxidation.Conclusions:This study identifies GSTM1 as a key inhibitor of fibroblast activation and cardiac fibrosis,highlighting its ability to target ferroptosis through redox regulation.AAV-mediated GSTM1 therapy demonstrates significant therapeutic potential for improving outcomes post-MI.
文摘Hydrogen peroxide(H_(2)O_(2)),as a green oxidant,plays a vital role in various applications,including environmental remediation,disinfection,and chemical synthesis[1].The conventional anthraquinone process,despite its industrial maturity and high yield,suffers from high energy consumption,carbon emissions,safety risks,and reliance on precious metals[2].Despite ongoing optimizations,a more sustainable alternative is urgently needed.The direct synthesis of hydrogen peroxide from water and oxygen has long been considered as an ideal alternative due to its theoretical 100%atom efficiency and environmental sustainability.
基金supported by the National Natural Science Foundation of China,No.82071442 (to LS)a grant from the Jilin Provincial Department of Finance,No.JLSWSRCZX2021-004 (to LS)。
文摘Alzheimer's disease is an age-related neurodegenerative disorder with a complex and incompletely understood pathogenesis. Despite extensive research, a cure for Alzheimer's disease has not yet been found. Oxidative stress mediates excessive oxidative responses, and its involvement in Alzheimer's disease pathogenesis as a primary or secondary pathological event is widely accepted. As a member of the selenium-containing antioxidant enzyme family, glutathione peroxidase 4 reduces esterified phospholipid hydroperoxides to maintain cellular redox homeostasis. With the discovery of ferroptosis, the central role of glutathione peroxidase 4 in anti-lipid peroxidation in several diseases, including Alzheimer's disease, has received widespread attention. Increasing evidence suggests that glutathione peroxidase 4 expression is inhibited in the Alzheimer's disease brain, resulting in oxidative stress, inflammation, ferroptosis, and apoptosis, which are closely associated with pathological damage in Alzheimer's disease. Several therapeutic approaches, such as small molecule drugs, natural plant products, and non-pharmacological treatments, ameliorate pathological damage and cognitive function in Alzheimer's disease by promoting glutathione peroxidase 4 expression and enhancing glutathione peroxidase 4 activity. Therefore, glutathione peroxidase 4 upregulation may be a promising strategy for the treatment of Alzheimer's disease. This review provides an overview of the gene structure, biological functions, and regulatory mechanisms of glutathione peroxidase 4, a discussion on the important role of glutathione peroxidase 4 in pathological events closely related to Alzheimer's disease, and a summary of the advances in small-molecule drugs, natural plant products, and non-pharmacological therapies targeting glutathione peroxidase 4 for the treatment of Alzheimer's disease. Most prior studies on this subject used animal models, and relevant clinical studies are lacking. Future clinical trials are required to validate the therapeutic effects of strategies targeting glutathione peroxidase 4 in the treatment of Alzheimer's disease.
基金supported by grants from the National Natural Science Foundation of China(22076104)the“Taishan Scholars”Program for Young Expert of Shandong Province(tsqn202103105).
文摘Ferroptosis,a type of programmed cell death,represents a distinct paradigm in cell biology.It is characterized by the iron-dependent accumulation of reactive oxygen species,which induce lipid peroxidation(LPO),and is orchestrated by the interplay between iron,lipid peroxides,and glutathione.In this review,we emphasize the frequently overlooked role of iron in LPO beyond the classical iron-driven Fenton reaction in several crucial processes that regulate cellular iron homeostasis,including iron intake and export as well as ferritinophagy,and the emerging roles of endoplasmic reticulum-resident flavoprotein oxidoreductases,especially P450 oxidoreductases,in modulating LPO.We summarize how various types of fatty acids(FAs),including saturated,monounsaturated,and polyunsaturated FAs,differentially influence ferroptosis when incorporated into phospholipids.Furthermore,we highlight the therapeutic potential of targeting LPO to mitigate ferroptosis and discuss the regulatory mechanisms of endogenous lipophilic radical-trapping antioxidants that confer resistance to ferroptosis,shedding light on therapeutic avenues for ferroptosis-associated diseases.
基金Supported by Bozhou Key Research and Development Project,No.bzzc2020031.
文摘BACKGROUND Fistula-in-ano is an abnormal tunnel formation linking the anal canal with the perineum and perianal skin.Multiple imagining methods are available to evaluate it,among which magnetic resonance imaging(MRI)is the most advanced nonin-vasive preoperative method.However,it is limited in its visualization function.AIM To investigate the use of intraluminal MRI for perianal fistulas via a novel direct MRI fistulography method.METHODS We mixed 3%hydrogen peroxide(HP)with gadolinium for HPMRI fistulogra-phy,retrospectively analyzing 60 cases of complex/recurrent fistula-in-ano using physical examination,trans-perineal ultrasonography(TPUS),low-spatial-reso-lution MRI,and high-resolution direct HPMRI fistulography.We assessed detec-tion rates of fistula tracks,internal openings,their relationship with anal sphinc-ters,and perianal abscesses using statistical analyses,including interobserver agreement(Kappa statistic),and compared results with intraoperative findings.RESULTS Surgical confirmation in 60 cases showed that high-resolution direct HPMRI fis-tulography provided superior detection rates for internal openings(153)and fistula tracks(162)compared to physical exams,TPUS,and low-spatial-resolution MRI(Z>5.7,P<0.05).The effectiveness of physical examination and TPUS was also inferior to that of our method for detecting perianal abscesses(54)(Z=6.773,3.694,P<0.05),whereas that of low-spatial-resolution MRI was not significantly different(Z=1.851,P=0.06).High-resolution direct HPMRI fistulography also achieved the highest interobserver agreement(Kappa:0.89,0.85,and 0.80),while low-spatial-resolution MRI showed moderate agreement(Kappa:0.78,0.74,and 0.69).TPUS and physical examination had lower agreement(Kappa range:0.33-0.63).CONCLUSION High-resolution direct HPMRI fistulography enhances the visualization of recurrent and complex fistula-in-ano,including branched fistulas,allowing for precise planning and improved surgical outcomes.
基金financially supported by the National Natu-ral Science Foundation of China(Nos.21805052 and 22227804)the Guangdong Basic and Applied Basic Research Foundation(No.2023B1515020110)+4 种基金the Science and Technology Research Project of Guangzhou(Nos.202102020787 and 2023A03J0030)the De-partment of Science&Technology of Guangdong Province(No.2022A156)the Key Laboratory of Optoelectronic Materials and Sensors in Guangdong Provincial Universities(No.2023KSYS008)the Key Discipline of Materials Science and Engineering,Bureau of Education of Guangzhou(No.20225546)the College Student Innovation and Entrepreneurship Training Program of Guangzhou University(No.XJ202311078029).
文摘Selective electrocatalysis of two-electron oxygen reduction reaction(2e^(-)ORR)has been recognized as a sustainable and on-site process for hydrogen peroxide(H_(2)O_(2))production.Great progress has been achieved for 2e^(-)ORR in alkaline media.However,it is challenged by insufficient activity and selectiv-ity of the catalysts in acidic electrolytes.Herein,we report sulfur-poisoned PtNi/C catalysts(PtNiSx/C)that could regulate ORR from the 4e^(-)to 2e^(-)pathway.The identified PtNiS0.6/C offers high activity in terms of onset potential of∼0.69 V(vs.RHE)and∼80%selectivity.The mass activity is also compara-ble and outperforms representative Pt-based precious and transition-metal-based catalysts.In addition,it is interestingly found that the Faradaic efficiency further increased to 95%during the long-term elec-trolysis test due to Ni atom surface migration.The electrochemical production of the H_(2)O_(2)system was applied to the electro-Fenton process,which has realized the effective degradation of organic pollutants.This work offers a strategy by sulfur poisoning PtNi/C catalyst to realize Pt-based 2e^(-)ORR active catalysts to electrolysis of H_(2)O_(2)in acidic media.
基金financial support from the National Natural Science Foundation of China(No.22279143).
文摘Hydrogen peroxide(H_(2)O_(2))is a crucial,eco-friendly oxidizing agent with a wide range of industrial,environmental,and biomedical applications.Traditional production methods,such as the anthraquinone process,face significant challenges in terms of energy consumption and environmental impact.As a sustainable alternative,photocatalytic H_(2)O_(2) production,driven by solar energy,has emerged as a promising approach.This review discusses the key advancements in photocatalytic H_(2)O_(2) synthesis,focusing on overcoming challenges such as charge recombination,selectivity for the two-electron oxygen reduction reaction(2e^(-)ORR),and catalyst stability.Recent innovations in photocatalyst design,including high-entropy materials,single-atom catalysts,and covalent organic frameworks(COFs),have significantly enhanced efficiency and stability.Furthermore,novel strategies for optimizing charge separation,light harvesting,and mass transfer are explored.The integration of artificial intelligence and bioinspired systems holds potential for accelerating progress in this field.This review provides a comprehensive overview of current challenges and cutting-edge solutions,offering valuable insights for the development of scalable,decentralized H_(2)O_(2) production systems that contribute to a more sustainable future.
基金Supported by the Special Research Fund of "National life Science&Technology Training Base" of Northwest A&F University[2006-(1)-061]~~
文摘[Objective] The aim of this study was to investigate the characteristics and mechanism of chemical emasculation in rapeseed and to provide the theoretical basis for development and utilization of new chemical gametocides.[Method] The activity of peroxidase,catalase and the content of hydrogen peroxide,malondialdehyde in leaves and flower buds of Brassica napus cultivars Qinyou No.3 and L89 induced by the chemical gametocide EXP in the course of male sterility were studied.[Result] Protective enzyme activity and the content of hydrogen peroxide,malondialdehyde in rapeseed treated with EXP changed significantly,which indicated that active oxygen metabolism was abnormal.Furthermore,there was a significant difference in the reaction degree of different cultivars and organs treated by EXP.[Conclusion] There was a correlation between the disturbance of active oxygen metabolism and the male sterility induced by chemical gametocide EXP.
文摘A mesocosm-based study was conducted to assess the effect of glucose and hydrogen peroxide on periphyton communities. These chemicals have been found to be effective at controlling cyanobacteria blooms in the water column but their impact on attached communities is unknown. The experimental design included a total of 4 treatments: control (no chemicals;3 replicates);hydrogen peroxide (3 replicates);glucose alone (3 different concentrations [no replicates]);and additive glucose (3 replicates). After 34 days, mean values of chlorophyll a were lower in all experimental treatments compared to the control;mean AFDM values were lower in all treatments except the unreplicated high glucose alone treatment. In contrast, mean autotrophic index values (AFDM/chlorophyll a) were greater in all treatments compared to the control, indicating heterotrophs were more resistant to the chemical treatments than autotrophs. Periphyton community biodiversity was much lower in the additive glucose and moderate glucose alone treatments than the hydrogen peroxide and control treatments. The relative abundance of the bacteria Asticcacaulis and Sphingorhabdus responded positively to the glucose treatments, whereas relative abundance of Nevskia and Caenimonas declined in both the hydrogen peroxide and glucose treatments. In terms of relative abundance, no cyanobacteria taxa were detected among the top 20 taxa. We conclude that the autotrophic component of periphyton communities is especially vulnerable to hydrogen peroxide and glucose treatments, and that any management strategy employing these chemicals should be aware of this potential impact.
基金supported by the National Key Research and Development Program of China(No.2022YFC3203301)the Natural Science Foundation of China(No.41406098).
文摘Pyrrhotite oxidation poses a big threat to water environment duo to its high potential for generating pollutants.Hydrogen peroxide,commonly found in natural water at micromolar concentrations,possesses much more aggressive oxidation ability than oxygen and can complicate the pyrrhotite oxidation process.Here,the effects of micromolar H_(2)O_(2) on the biotic and abiotic oxidation of pyrrhotite were examined at pH 1.93 and 6.45,respectively.Pyrrhotite oxidation was much more severe in acidic solutions compared to near neutral solutions.Jarosite with a high Fe/S molar ratio was widely detected in the precipitate collected in acidic solutions,and the introduction of external H_(2)O_(2) influenced the crystallinity of jarosite.A layer of iron-deficient iron-sulfur oxide formed on the surface of pyrrhotite prevents its continuous oxidation,and the presence of Acidithiobacillus ferrooxidans enhanced this situation by promoting the release of Fe from the pyrrhotite.Additionally,the presence of external micromolar H_(2)O_(2) also determined the elemental state on pyrrhotite surface,as it found that the contribution of Fe^(3+)and S(S^(4+)and S^(6+))species on pyrrhotite surface increased with the increase of H_(2)O_(2) concentration in the solutions,especially in the presence of Acidithiobacillus ferrooxidans.
文摘This letter addresses Pravda's innovative review,which proposes hydrogen pe-roxide as the primary pathogenic factor in ulcerative colitis(UC).Although the author presents intriguing mechanistic insights and reports encouraging clinical outcomes with reducing agents,several methodological and clinical considera-tions require discussion.We examine three key aspects:The selective evidence synthesis approach;the need for rigorous clinical validation of proposed thera-pies;and the integration of this novel hypothesis with established inflammatory bowel disease pathogenesis.Given the complexity of UC,future therapeutic ad-vances may require collaborative approaches that integrate redox-based mecha-nisms into existing evidence-based frameworks rather than replacing current paradigms.
基金supported by the National Natural Science Foundation of China(22361024 and 22471055)Natural Science Foundation of Jiangxi Province(20232ACB203001)+1 种基金Natural Science Foundation of Hebei Province(B2024202021,B2022202039)S&T Program of Hebei(236Z4308G)。
文摘The photocatalytic hydrogen peroxide(H_(2)O_(2))production by graphitic carbon nitride is a sustainable and environment-benign alternative approach of conventional anthraquinone autoxidation technology,but it is great challenges to promote two-electron O_(2)reduction and water oxidation.Herein,we present the well-dispersed graphitic carbon nitride quantum dots decorated with cyano groups(Na-CNQD and K-CNQD)by thermal polymerization of melamine in the presence of metal fluoride.The quantum confinement and edge effect have endowed the photocatalysts with rich active sites,wide light absorption range and the inhibited charge recombination.The cyano moieties function as O_(2)reduction centers to accept the photogenerated electrons and facilitate their rapid transfer to O_(2)molecules.This process enables the selective two-electron reduction of O_(2),leading to the production of H_(2)O_(2).Concurrently,the valence band holes on the heptazine moiety oxidize water into H_(2)O_(2).These synergistic effects promote photocatalytic H_(2)O_(2)production from O_(2)and H_(2)O without the need for additional photosensitizers,organic scavengers and co-catalysts.In contrast,pristine carbon nitride nanosheets remain inactive under the same conditions.This study offers new strategies for rational design of carbon-based materials for solar-to-chemical energy conversion.
基金the financial support from the National Natural Science Foundation of China(Nos.82060626,22004137,22164022,22174147,22074151,22374153,22174148)Excellent Youth scientific and technological talents of Guizhou Province(No.Qiankehe platform talents[2021]5638)+3 种基金Talents of Guizhou Science and Technology Cooperation Platform(No.[2020]4104)Science and Technology Innovation Team of Higher Education of Guizhou Provincial Education Department(No.Qianjiaoji[2023]073)Future Science and Technology Elite Talent Cultivation Project of Zunyi Medical University(No.ZYSE-2021-01)Zunyi Science and Technology Plan Project(No.Zunshi Keren Platform[2023]2)。
文摘Ferroptosis is a new regulated cell death process executed by lipid peroxidation(LPO)of polyunsaturated fatty acids.Lipid droplets(LDs),as an important organelle for lipid storage and metabolism,are probably a major site of LPO and play critical roles in the regulation of ferroptosis.However,the detailed study on LPO in LDs has not been carried out because of the lack of LD-targeting tools for the in situ monitoring of LPO.Herein,the first LD-targeting LPO fluorescence probe(LD-LPO)has been developed.LD-LPO exhibits a rapid and selective fluorescence enhancement at 518 nm,which is unaffected by highly destructive reactive oxygen species(e.g.,hydroxyl radical)and environmental factor changes(e.g.,polarity and viscosity).LD-LPO is capable of targeting LDs and visualizing LPO within LDs in situ during erastin-or(1S,3R)-RSL3(RSL3)-induced ferroptosis.Moreover,LD-LPO has also been used to image LPO in the ferroptosis-associated non-alcoholic fatty liver disease(NAFLD),and to evaluate the medicine treatment of NAFLD with saroglitazar,demonstrating its utility for monitoring LPO levels in biosystems.The favorable analytical and imaging performance of LD-LPO may allow its application in more ferroptosisassociated physiological and pathological processes.
基金supported by the research project“Green-health-safety Nexus for New Urban Spaces-GreeNexUS”(HORIZON MSCA-2021 DN,Marie Sklodowska-Curie Actions)Grant Agreement No.101073437:research grant under the title"Impact Absorbing Pavements with Improved Accessibility Features(DC9-IAP)".
文摘Enhancing rubber-bitumen compatibility is crucial to improve pavement performance and durability.To investigate the compatibility improvement between H2O2-activated waste crumb rubber(AWCR)and bitumen,coarse and fine waste crumb rubber(WCR)were treated and analyzed through multi-scale characterization and molecular simulation.Microstructure and chemical changes of WCR and AWCR were analyzed with scanning electron microscope(SEM),contact angle tests and Fourier transform infrared spectroscopy(FTIR).Compatibility was also indirectly evaluated through modified boiling tests and storage stability tests.Besides,molecular dynamics was used to explore the interaction between WCR/AWCR and bitumen.SEM,contact angle,and FTIR results showed bond breakage of C=C and C–C and increased polar groups like–OH and–COOH in AWCR,resulting in a rougher texture and higher surface energy.Compared with WCR,AWCR showed a lower bitumen stripping rate after boiling,and the binder with AWCR also had a lower softening point difference and segregation rate after storage.Molecular dynamics simulations further confirmed that AWCR has a closer solubility parameter and higher binding energy to bitumen than WCR,reflected in a relatively slower diffusion rate.This study provides comprehensive evidence for an eco-friendly method of WCR surface treatment for more efficient recycling of tire rubber in asphalt pavements.
基金supported by the National Natural Science Foundation of China(22479040,22279138)the Natural Science Foundation of Tianjin(24JCQNJC00360)+3 种基金Government Guide the Development of Local Science and Technology Special Funds(246Z3707G)Young Scientific and Technological Talents(Level Three)in Tianjin(QN20230343)Hebei Yanzhao Golden Platform Talent Gathering Plan Backbone Talent Project(HJYB202501)the Natural Science Foundation of Liaoning Province(2022-MS023)。
文摘Photocatalytic H_(2)O_(2) production still confronts the challenges of its dependence on organic electron donors or high-purity O_(2),which restricts the practical application,and there are few studies on the photo synthesis of H_(2)O_(2) via both oxygen reduction reaction(ORR)and water oxidation reaction(WOR).In this paper,bismuth yttrium oxyhalides Bi_(2)YO_(4)X(X=Cl,Br,or I)are demonstrated to afford sufficient driving forces to produce H_(2)O_(2) in the absence of sacrificial reagents.After modification with Pt and IrO_(2) as cocatalysts,which can selectively promote both ORR and WOR reactions on Bi_(2)YO_(4)Cl,the IrO_(2)-Pt/Bi_(2)YO_(4)Cl sample yields H_(2)O_(2) production activity of 647μmol L^(-1)h^(-1)with negligible decay in the long-term reaction using only H_(2)O and an air atmosphere as the electron donors and O_(2) source.Detailed characterizations reveal that the ORR reaction obeys a two-electron pathway.We present the first example of oxyhalides(Bi_(2)YO_(4)X)capable of efficient photocata lytic H_2O_(2) generation with record-breaking activity.
基金supported by the National Natural Science Foundation of China(Nos.22102073,22075147).
文摘As a versatile and environmentally benign oxidant,hydrogen peroxide(H_(2)O_(2))is highly desired in sanitation,disinfection,environmental remediation,and the chemical industry.Compared with the conventional anthraquinone process,the electrosynthesis of H_(2)O_(2)through the two-electron oxygen reduction reaction(2e^(−)ORR)is an efficient,competitive,and promising avenue.Electrocatalysts and devices are two core factors in 2e^(−)ORR,but the design principles of catalysts for different pH conditions and the development trends of relevant synthesis devices remain unclear.To this end,this review adopts a multiscale perspective to summarize recent advancements in the design principles,catalytic mechanisms,and application prospects of 2e^(−)ORR catalysts,with a particular focus on the influence of pH conditions,aiming at providing guidance for the selective design of advanced 2e^(−)ORR catalysts for highly-efficient H_(2)O_(2)production.Moreover,in response to diverse on-site application demands,we elaborate on the evolution of H_(2)O_(2)electrosynthesis devices,from rotating ring-disk electrodes and H-type cells to diverse flow-type cells.We elaborate on their characteristics and shortcomings,which can be beneficial for their further upgrades and customized applications.These insights may inspire the rational design of innovative catalysts and devices with high performance and wide serviceability for large-scale implementations.