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Contribution of mechanical forces to structural synaptic plasticity:insights from 3D cellular motility mechanisms
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作者 Rita O.Teodoro Mafalda Ribeiro Ramos Lara Carvalho 《Neural Regeneration Research》 SCIE CAS 2025年第7期1995-1996,共2页
Cells,tissues,and organs are constantly subjected to the action of mechanical forces from the extracellular environment-and the nervous system is no exception.Cell-intrinsic properties such as membrane lipid compositi... Cells,tissues,and organs are constantly subjected to the action of mechanical forces from the extracellular environment-and the nervous system is no exception.Cell-intrinsic properties such as membrane lipid composition,abundance of mechanosensors,and cytoskeletal dynamics make cells more or less likely to sense these forces.Intrinsic and extrinsic cues are integrated by cells and this combined information determines the rate and dynamics of membrane protrusion growth or retraction(Yamada and Sixt,2019).Cell protrusions are extensions of the plasma membrane that play crucial roles in diverse contexts such as cell migration and neuronal synapse formation.In the nervous system,neurons are highly dynamic cells that can change the size and number of their pre-and postsynaptic elements(called synaptic boutons and dendritic spines,respectively),in response to changes in the levels of synaptic activity through a process called plasticity.Synaptic plasticity is a hallmark of the nervous system and is present throughout our lives,being required for functions like memory formation or the learning of new motor skills(Minegishi et al.,2023;Pillai and Franze,2024). 展开更多
关键词 PLASTICITY STRUCTURAL mechanismS
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Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite
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作者 Feng Zhang Chenyang Zhang +5 位作者 Linlin Wu Wei Sun Hongliang Zhang Jianhua Chen Yong Pei Songjiang Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期335-345,共11页
The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth insight.Therefore,the depression mechanism of sulfite ... The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth insight.Therefore,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)calculations.The X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption mechanisms.First,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and galena.Then,sulfite ions were chelated with lead ions to form PbSO_(3)in solution.The hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than galena.The interaction between sulfite ions and lead ions could effectively inhibit the activation of sphalerite.In addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of perxanthate.However,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some extent.This study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite. 展开更多
关键词 SPHALERITE GALENA sulfite ion density functional theory depression mechanism
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Mechanism for Hydrothermal-carbothermal Synthesis of AlN Nanopowders
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作者 FENG Guanzheng YANG Jian +3 位作者 ZHOU Du CHEN Qiming XU Wentao ZHOU Youfu 《无机材料学报》 北大核心 2025年第1期104-110,I0009-I0011,共10页
Currently,the carbothermal reduction-nitridation(CRN)process is the predominant method for preparing aluminum nitride(AlN)powder.Although AlN powder prepared by CRN process exhibits high purity and excellent sintering... Currently,the carbothermal reduction-nitridation(CRN)process is the predominant method for preparing aluminum nitride(AlN)powder.Although AlN powder prepared by CRN process exhibits high purity and excellent sintering activity,it also presents challenges such as the necessity for high reaction temperatures and difficulties in achieving uniform mixing of its raw materials.This study presents a comprehensive investigation into preparation process of AlN nanopowders using a combination of hydrothermal synthesis and CRN.In the hydrothermal reaction,a homogeneous composite precursor consisting of carbon and boehmite(γ-AlOOH)is synthesized at 200℃using aluminum nitrate as the aluminum source,sucrose as the carbon source,and urea as the precipitant.During the hydrothermal process,the precursor develops a core-shell structure,with boehmite tightly coated with carbon(γ-AlOOH@C)due to electrostatic attraction.Compared with conventional precursor,the hydrothermal hybrid offers many advantages,such as ultrafine particles,uniform particle size distribution,good dispersion,high reactivity,and environmental friendliness.The carbon shell enhances thermodynamic stability of γ-Al_(2)O_(3) compared to the corundum phase(α-Al_(2)O_(3))by preventing the loss of the surface area in alumina.This stability enables γ-Al_(2)O_(3) to maintain high reactivity during CRN process,which initiates at 1300℃,and concludes at 1400℃.The underlying mechanisms are substantiated through experiments and thermodynamic calculations.This research provides a robust theoretical and experimental foundation for the hydrothermal combined carbothermal preparation of non-oxide ceramic nanopowders. 展开更多
关键词 aluminum nitride carbothermal reduction-nitridation mechanism hydrothermal synthesis PRECURSOR
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Decoding molecular mechanisms:brain aging and Alzheimer's disease
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作者 Mahnoor Hayat Rafay Ali Syed +9 位作者 Hammad Qaiser Mohammad Uzair Khalid Al-Regaiey Roaa Khallaf Lubna Abdullah Mohammed Albassam Imdad Kaleem Xueyi Wang Ran Wang Mehwish SBhatti Shahid Bashir 《Neural Regeneration Research》 SCIE CAS 2025年第8期2279-2299,共21页
The complex morphological,anatomical,physiological,and chemical mechanisms within the aging brain have been the hot topic of research for centuries.The aging process alters the brain structure that affects functions a... The complex morphological,anatomical,physiological,and chemical mechanisms within the aging brain have been the hot topic of research for centuries.The aging process alters the brain structure that affects functions and cognitions,but the worsening of such processes contributes to the pathogenesis of neurodegenerative disorders,such as Alzheimer's disease.Beyond these observable,mild morphological shifts,significant functional modifications in neurotransmission and neuronal activity critically influence the aging brain.Understanding these changes is important for maintaining cognitive health,especially given the increasing prevalence of age-related conditions that affect cognition.This review aims to explore the age-induced changes in brain plasticity and molecular processes,differentiating normal aging from the pathogenesis of Alzheimer's disease,thereby providing insights into predicting the risk of dementia,particularly Alzheimer's disease. 展开更多
关键词 Alzheimer’s disease brain aging cognitive health DEMENTIA molecular mechanisms neuronal activity NEUROPLASTICITY NEUROTRANSMISSION
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An Iterated Greedy Algorithm with Memory and Learning Mechanisms for the Distributed Permutation Flow Shop Scheduling Problem
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作者 Binhui Wang Hongfeng Wang 《Computers, Materials & Continua》 SCIE EI 2025年第1期371-388,共18页
The distributed permutation flow shop scheduling problem(DPFSP)has received increasing attention in recent years.The iterated greedy algorithm(IGA)serves as a powerful optimizer for addressing such a problem because o... The distributed permutation flow shop scheduling problem(DPFSP)has received increasing attention in recent years.The iterated greedy algorithm(IGA)serves as a powerful optimizer for addressing such a problem because of its straightforward,single-solution evolution framework.However,a potential draw-back of IGA is the lack of utilization of historical information,which could lead to an imbalance between exploration and exploitation,especially in large-scale DPFSPs.As a consequence,this paper develops an IGA with memory and learning mechanisms(MLIGA)to efficiently solve the DPFSP targeted at the mini-malmakespan.InMLIGA,we incorporate a memory mechanism to make a more informed selection of the initial solution at each stage of the search,by extending,reconstructing,and reinforcing the information from previous solutions.In addition,we design a twolayer cooperative reinforcement learning approach to intelligently determine the key parameters of IGA and the operations of the memory mechanism.Meanwhile,to ensure that the experience generated by each perturbation operator is fully learned and to reduce the prior parameters of MLIGA,a probability curve-based acceptance criterion is proposed by combining a cube root function with custom rules.At last,a discrete adaptive learning rate is employed to enhance the stability of the memory and learningmechanisms.Complete ablation experiments are utilized to verify the effectiveness of the memory mechanism,and the results show that this mechanism is capable of improving the performance of IGA to a large extent.Furthermore,through comparative experiments involving MLIGA and five state-of-the-art algorithms on 720 benchmarks,we have discovered that MLI-GA demonstrates significant potential for solving large-scale DPFSPs.This indicates that MLIGA is well-suited for real-world distributed flow shop scheduling. 展开更多
关键词 Distributed permutation flow shop scheduling MAKESPAN iterated greedy algorithm memory mechanism cooperative reinforcement learning
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Joint Feature Encoding and Task Alignment Mechanism for Emotion-Cause Pair Extraction
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作者 Shi Li Didi Sun 《Computers, Materials & Continua》 SCIE EI 2025年第1期1069-1086,共18页
With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant importance.Emotion-cause pair extraction enables the identification of causal relationships between emotions... With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant importance.Emotion-cause pair extraction enables the identification of causal relationships between emotions and their triggers within a text,facilitating a deeper understanding of expressed sentiments and their underlying reasons.This comprehension is crucial for making informed strategic decisions in various business and societal contexts.However,recent research approaches employing multi-task learning frameworks for modeling often face challenges such as the inability to simultaneouslymodel extracted features and their interactions,or inconsistencies in label prediction between emotion-cause pair extraction and independent assistant tasks like emotion and cause extraction.To address these issues,this study proposes an emotion-cause pair extraction methodology that incorporates joint feature encoding and task alignment mechanisms.The model consists of two primary components:First,joint feature encoding simultaneously generates features for emotion-cause pairs and clauses,enhancing feature interactions between emotion clauses,cause clauses,and emotion-cause pairs.Second,the task alignment technique is applied to reduce the labeling distance between emotion-cause pair extraction and the two assistant tasks,capturing deep semantic information interactions among tasks.The proposed method is evaluated on a Chinese benchmark corpus using 10-fold cross-validation,assessing key performance metrics such as precision,recall,and F1 score.Experimental results demonstrate that the model achieves an F1 score of 76.05%,surpassing the state-of-the-art by 1.03%.The proposed model exhibits significant improvements in emotion-cause pair extraction(ECPE)and cause extraction(CE)compared to existing methods,validating its effectiveness.This research introduces a novel approach based on joint feature encoding and task alignment mechanisms,contributing to advancements in emotion-cause pair extraction.However,the study’s limitation lies in the data sources,potentially restricting the generalizability of the findings. 展开更多
关键词 Emotion-cause pair extraction interactive information enhancement joint feature encoding label consistency task alignment mechanisms
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Pyroptosis,ferroptosis,and autophagy in spinal cord injury:regulatory mechanisms and therapeutic targets
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作者 Qingcong Zheng Du Wang +1 位作者 Rongjie Lin Weihong Xu 《Neural Regeneration Research》 SCIE CAS 2025年第10期2787-2806,共20页
Regulated cell death is a form of cell death that is actively controlled by biomolecules.Several studies have shown that regulated cell death plays a key role after spinal cord injury.Pyroptosis and ferroptosis are ne... Regulated cell death is a form of cell death that is actively controlled by biomolecules.Several studies have shown that regulated cell death plays a key role after spinal cord injury.Pyroptosis and ferroptosis are newly discovered types of regulated cell deaths that have been shown to exacerbate inflammation and lead to cell death in damaged spinal cords.Autophagy,a complex form of cell death that is interconnected with various regulated cell death mechanisms,has garnered significant attention in the study of spinal cord injury.This injury triggers not only cell death but also cellular survival responses.Multiple signaling pathways play pivotal roles in influencing the processes of both deterioration and repair in spinal cord injury by regulating pyroptosis,ferroptosis,and autophagy.Therefore,this review aims to comprehensively examine the mechanisms underlying regulated cell deaths,the signaling pathways that modulate these mechanisms,and the potential therapeutic targets for spinal cord injury.Our analysis suggests that targeting the common regulatory signaling pathways of different regulated cell deaths could be a promising strategy to promote cell survival and enhance the repair of spinal cord injury.Moreover,a holistic approach that incorporates multiple regulated cell deaths and their regulatory pathways presents a promising multi-target therapeutic strategy for the management of spinal cord injury. 展开更多
关键词 AUTOPHAGY cell death ferroptosis INFLAMMATION pathological mechanisms PYROPTOSIS regulated cell death regulatory pathways spinal cord injury therapeutic targets
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Molecular Mechanisms of the CIRBP Family in Tumors: Current Status and Future Perspectives
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作者 Yu Cai Tingting Wang Yuan Zhan 《Journal of Cancer Therapy》 2025年第2期63-76,共14页
The Cold-Inducible RNA-Binding Protein (CIRBP) family plays a pivotal role in cellular stress responses and tumorigenesis. Recent studies have increasingly highlighted the expression alterations of CIRBP family member... The Cold-Inducible RNA-Binding Protein (CIRBP) family plays a pivotal role in cellular stress responses and tumorigenesis. Recent studies have increasingly highlighted the expression alterations of CIRBP family members across various cancer types and their potential molecular mechanisms. This review provides a comprehensive overview of the structural characteristics and functions of the CIRBP family, alongside their expression profiles in tumors and the regulatory molecular mechanisms involved. By synthesizing current knowledge, this review aims to offer new insights and directions for future cancer therapies, emphasizing the importance of CIRBP proteins in oncological research. 展开更多
关键词 CIRBP Family TUMORS Molecular mechanisms RNA-Binding Proteins Cellular Stress
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Concurrent occurrence of adenocarcinoma and urothelial carcinoma of the prostate:Coexistence mechanisms from multiple perspectives
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作者 Xu-Chang Liu Yu-Xiang Liu Chun Liu 《World Journal of Clinical Cases》 2025年第12期5-9,共5页
This article discusses the coexistence of prostate adenocarcinoma and prostate urothelial carcinoma.Combining existing literature and research results,the potential mechanisms of the co-occurrence of these two cancers... This article discusses the coexistence of prostate adenocarcinoma and prostate urothelial carcinoma.Combining existing literature and research results,the potential mechanisms of the co-occurrence of these two cancers are explored,including the role of androgen receptor,gene mutations,and their complex interactions in cell signaling pathways,etc.Also,the hypothesis of prostate cancer transformation into urothelial carcinoma is explained from some perspectives,including tumor multipotent stem cell differentiation,epithelial-mesenchymal transition,mesenchymal-epithelial transition,and other mechanisms.Ultimately,the goal is to provide more accurate diagnoses and more personalized treatments in clinical practice,as well as to lay the foundation for improving patient prognoses in the future. 展开更多
关键词 Prostate adenocarcinoma Prostate urothelial carcinoma Coexistence mechanism Transformation mechanism TUMOR
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National collaboration mechanism for standardization research institutes established
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作者 靳吉丽 《China Standardization》 2025年第2期16-35,共20页
Hosted by China National Institute of Standardization(CNIS),the Inaugural Ceremony of the National Collaboration Mechanism for Standardization Research Institutes and the 4th Roundtable on Standardization Reform and D... Hosted by China National Institute of Standardization(CNIS),the Inaugural Ceremony of the National Collaboration Mechanism for Standardization Research Institutes and the 4th Roundtable on Standardization Reform and Development were held in Beijing on November 29,2024,to implement the National Standardization Development Outline and establish a standardization science and technology system with the comprehensive standardization research institute at the national level as the leader,and standardization research institutes at the industrial,regional and local levels as the mainstay. 展开更多
关键词 ROUND STANDARDIZATION mechanism
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A Dynamic Knowledge Base Updating Mechanism-Based Retrieval-Augmented Generation Framework for Intelligent Question-and-Answer Systems
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作者 Yu Li 《Journal of Computer and Communications》 2025年第1期41-58,共18页
In the context of power generation companies, vast amounts of specialized data and expert knowledge have been accumulated. However, challenges such as data silos and fragmented knowledge hinder the effective utilizati... In the context of power generation companies, vast amounts of specialized data and expert knowledge have been accumulated. However, challenges such as data silos and fragmented knowledge hinder the effective utilization of this information. This study proposes a novel framework for intelligent Question-and-Answer (Q&A) systems based on Retrieval-Augmented Generation (RAG) to address these issues. The system efficiently acquires domain-specific knowledge by leveraging external databases, including Relational Databases (RDBs) and graph databases, without additional fine-tuning for Large Language Models (LLMs). Crucially, the framework integrates a Dynamic Knowledge Base Updating Mechanism (DKBUM) and a Weighted Context-Aware Similarity (WCAS) method to enhance retrieval accuracy and mitigate inherent limitations of LLMs, such as hallucinations and lack of specialization. Additionally, the proposed DKBUM dynamically adjusts knowledge weights within the database, ensuring that the most recent and relevant information is utilized, while WCAS refines the alignment between queries and knowledge items by enhanced context understanding. Experimental validation demonstrates that the system can generate timely, accurate, and context-sensitive responses, making it a robust solution for managing complex business logic in specialized industries. 展开更多
关键词 Retrieval-Augmented Generation Question-and-Answer Large Language Models Dynamic Knowledge Base Updating mechanism Weighted Context-Aware Similarity
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Plasma Combined with Drugs:Synergistic Mechanisms for Eliminating Cancer Cells
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作者 Jie Bai 《Journal of Clinical and Nursing Research》 2025年第1期243-248,共6页
With the continuous advancement of cancer treatment methods, plasma combined with drug therapy has garnered widespread attention as an emerging therapeutic strategy. This paper elaborates on the generation and charact... With the continuous advancement of cancer treatment methods, plasma combined with drug therapy has garnered widespread attention as an emerging therapeutic strategy. This paper elaborates on the generation and characteristics of plasma, as well as its mechanisms of action on cancer cells when used alone, including the production of reactive oxygen and nitrogen species, and damage to cancer cell membranes, and organelles. It emphasizes the synergistic mechanisms observed when plasma is combined with various anticancer drugs (e.g., chemotherapeutic agents, targeted drugs, and immunotherapies). The analysis focuses on enhancing drug uptake, promoting the activation of drug action targets, and improving the tumor microenvironment. These insights provide a theoretical basis for optimizing plasma-drug combination therapy for cancer. 展开更多
关键词 PLASMA Anticancer drugs SYNERGY Enhancement mechanisms
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Acupuncture for postoperative ileus:Advancement and underlying mechanisms
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作者 Yang Ye Xi-Yan Xin +6 位作者 Ze-Jun Huo Yu-Tian Zhu Rui-Wen Fan Hao-Lin Zhang Yu Gao Hong-Bo Shen Dong Li 《World Journal of Gastrointestinal Surgery》 2025年第2期11-15,共5页
Postoperative ileus(POI)remains a prevalent and significant challenge following abdominal surgeries,precipitating patient distress,prolonged hospital stays,and escalated medical expenditures.Conventionally addressed v... Postoperative ileus(POI)remains a prevalent and significant challenge following abdominal surgeries,precipitating patient distress,prolonged hospital stays,and escalated medical expenditures.Conventionally addressed via pharmacological interventions,POI is increasingly being explored through adjunctive therapeutic strategies,with acupuncture gaining recognition as a promising option.Acupuncture has demonstrated encouraging potential in promoting gastrointestinal motility in patients with POI.Moreover,recent research has shed light on the therapeutic mechanisms underlying its efficacy.This article aims to present a comprehensive overview of acupuncture as a treatment for POI,highlighting advancements in clinical research and recent elucidations of its mechanistic underpinnings.It aspires to contribute a pivotal reference point for scholars and enthusiasts keen on garnering a deeper understanding of acupuncture’s role in managing POI. 展开更多
关键词 ACUPUNCTURE Gastrointestinal motility mechanism PATIENTS Postoperative ileus
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Metabolic mechanism of dietary factors and effect of dietary types associated with hyperuricemia:a review
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作者 Kaina Qiao Xuewei Zhou +3 位作者 Lili Zhang Wangang Zhang Baoguo Sun Yuyu Zhang 《Food Science and Human Wellness》 2025年第3期835-849,共15页
Globally,hyperuricemia is a growing health,social,and economic problem which could cause gout,chronic kidney diseases and other diseases.There are increasing evidences that a sensible diet makes sense to reduce the ri... Globally,hyperuricemia is a growing health,social,and economic problem which could cause gout,chronic kidney diseases and other diseases.There are increasing evidences that a sensible diet makes sense to reduce the risk of hyperuricemia.This review aims to explore the metabolic mechanism of dietary factors and effects of dietary types associated with hyperuricemia.Recommendations for dietary modification to prevent hyperuricemia are as following:decreasing intake of animal organs,seafood,sugar-sweetened,and alcohol beverages is essential;choosing water or unsweetened tea and coffee instead of sweetened beverages is beneficial;and increasing intake of vegetables,reduced-fat dairy products,foods containing fiber,micronutrients and unsaturated fatty acids is helpful.In addition,consumption of fruits and legumes in moderation is advantageous,and low-fructose of fruits and low-purine of non-soy beans are recommended.Moreover,personalized diet needs to be emphasized for hyperuricemic patients accompanied with diverse metabolic diseases. 展开更多
关键词 PURINE Metabolic mechanism Dietary types HYPERURICEMIA Personalized diet
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Elucidating the anti-obesity phytochemicals in Chenpi and their molecular mechanisms
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作者 Jinhai Luo Weiqi Yan +1 位作者 Zhi Chen Baojun Xu 《Food Science and Human Wellness》 2025年第4期1224-1238,共15页
Obesity has become a significant global public health issue.Previous studies have found that the Chenpi has the anti-obesity activity.However,the anti-obesity phytochemicals and their mechanisms are still unclear.This... Obesity has become a significant global public health issue.Previous studies have found that the Chenpi has the anti-obesity activity.However,the anti-obesity phytochemicals and their mechanisms are still unclear.This study investigated the anti-obesity phytochemicals and molecular mechanisms involved in treating obesity by Chenpi through network pharmacology and molecular docking.A total of 17 bioactive phytochemicals from Chenpi and its 475 related anti-obesity targets have been identified.The KEGG pathway analysis showed that the PI3K/Akt signaling pathway,MAPK signaling pathway,AMPK signaling pathway,and nuclear factor kappa B signaling pathway are the main signaling pathways involved in the anti-obesity effect of Chenpi.According to molecular docking analysis,the phytochemicals of Chenpi can bind to central anti-obesity targets.Based on the ADMET analysis and network pharmacology results,tangeretin exhibited the lowest predicted toxicity and potential for anti-obesity effects.In the in vitro lipid accumulation model,tangeretin effectively suppressed the free fatty acid-induced lipid in Hep G2 cells by upregulating the PI3K/Akt/GSK3βsignaling pathway based on the result of q-PCR and Western blotting.The outcomes of this research give insights for future research on the anti-obesity phytochemicals and molecular mechanisms derived from Chenpi,also providing the theoretical basis for developing anti-obesity functional foods based on Chenpi. 展开更多
关键词 Chenpi PHYTOCHEMICALS OBESITY Network pharmacology Molecular mechanism Signaling pathway
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Discovery and mechanism of anti-hypertensive effect of a novel tripeptide(SYP)from medicinal fungus Ganoderma lingzhi
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作者 Qiang Wu Feijun Luo +4 位作者 Jia Huang Ping Huang Yongnan Liu Xiaoling Wang Gaoqiang Liu 《Food Science and Human Wellness》 2025年第2期509-524,共16页
Ganoderma lingzhi is a new species of the prize medicinal mushroom Ganoderma(Agaricomycetes).Using angiotensin I-converting enzyme(ACE)as a target,a tripeptide Ser-Tyr-Pro(SYP)was discovered with preponderant ACE inhi... Ganoderma lingzhi is a new species of the prize medicinal mushroom Ganoderma(Agaricomycetes).Using angiotensin I-converting enzyme(ACE)as a target,a tripeptide Ser-Tyr-Pro(SYP)was discovered with preponderant ACE inhibitory activity with an 50%inhibiting concentration(IC_(50))value of 62.50μg/mL attribute to the formed salt bridge and hydrogen bonds between SYP and ACE.SYP even maintained superior bioactivity after intestinal digestion,and exerted no cytotoxicity,but presented incomplete bioavailability in blood of spontaneous hypertensive rats(SHRs).Furthermore,it performed antihypertensive effect in vivo by inhibiting the influx of Ca^(2+)through activating endothelial NO synthase(e NOS)/NO/guanosine 3',5'-cyclic monophosphate(c GMP)pathway,accompanied by attenuating angiotensin II(Ang II)/NADPH oxidase(NOX)/reactive oxygen species(ROS)pathway.This work not only discoverers a novel pharmacological ingredient from medicinal mushroom G.lingzhi for hypertension therapy,but also provides an insight into molecular mechanism of the ACE inhibitory peptide(ACEIP)on lowering blood pressure. 展开更多
关键词 Antihypertensive peptide Ganoderma lingzhi Gene microarray Molecular mechanism
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Collapse characteristics and mechanisms of shallow cross roadways under mining blasting disturbance
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作者 XU Zhenyang LIU Aobo +3 位作者 REN Fuqiang YAN Yiran ZHANG Zuofu WANG Xuesong 《Journal of Mountain Science》 2025年第3期1101-1118,共18页
Cross roadway collapses are a common occurrence in underground mining operations.While the influence of mining blasts on the stability of surrounding rock is acknowledged,the underlying mechanisms remain inadequately ... Cross roadway collapses are a common occurrence in underground mining operations.While the influence of mining blasts on the stability of surrounding rock is acknowledged,the underlying mechanisms remain inadequately understood.This study investigates the characteristics and mechanisms of collapse in a shallow buried cross roadway subjected to mining blast disturbances,drawing insights from an engineering project in Anshan City,Northeast China.A strain-softening model based on unified strength theory was developed to effectively calculate and analyze the loosened zone thickness and surrounding rock displacement.The PFC3D-FLAC3D coupling method was employed to clarify the concentrated collapse area within the cross roadway,providing insight into the collapse mechanism through a cross-sectional model of the concentrated region.Results demonstrate that 50%of the cross roadway collapsed following the mining blast.Subsidence at the intersection was approximately one-fifth(0.66 m)of cross roadway’s net height,exceeding subsidence in other areas by 1.3.Under the action of repeated mining blasting,the cross section of the connection roadway forms a semi-elliptical high tensile stress zone.After the cumulative damage of the surrounding rock of the connection roadway exceeds the ultimate yield strength,the cumulative stress release causes the tensile failure of the surrounding rock.The plastic zone of the connecting roadway expands to three times of the initial,and continues to develop.The surrounding rock on both sides experienced tensile stress,cumulative stress release,and the vertical propagation of tensile cracks. 展开更多
关键词 Cross roadway PFC-FLAC coupling Blast vibration Collapse mechanism
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Understanding the mechanism underlying the anti-inflammatory effect of dietary flavonoids on IBD:a focus on gut microbiota and its metabolites involved in SCFA,bile acid,tryptophan and lipopolysaccharides
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作者 Huihui Xiong Hui Chen +3 位作者 Lingli Chen Kehui Ouyang Suyun Lin Wenjun Wang 《Food Science and Human Wellness》 2025年第2期385-403,共19页
Inflammatory bowel disease(IBD)is a chronic gastrointestinal disease with a high incidence.Treatment for IBD includes medications and diet,and common anti-inflammatory medications have limitations like drug resistance... Inflammatory bowel disease(IBD)is a chronic gastrointestinal disease with a high incidence.Treatment for IBD includes medications and diet,and common anti-inflammatory medications have limitations like drug resistance and serious adverse effects.Accumulating evidence has demonstrated that dietary flavonoids exhibit an alleviative effect on IBD by influencing gut microbiota.The microbiota-derived metabolites also regulate IBD and maintain intestinal homeostasis.In this review,we investigate the therapeutic effect of gut microbiota and metabolites on IBD by intestinal immune and intestinal barrier function.We demonstrate the underlying mechanism of dietary flavonoids as an anti-inflammatory molecule alleviating IBD by regulating gut microbiota,short chain fatty acid(SCFA),bile acid(BA),tryptophan(Trp)metabolism and lipopolysaccharides(LPS)-toll-like receptor 4(TLR4)signaling pathway.Based on structural differences of flavonoids,we summarize the recent research progress on the role of different dietary flavonoids in alleviating IBD by gut microbiota and metabolites in animal and clinical trials.This review indicates that dietary flavonoids targeting gut microbiota and metabolites provide a promising strategy for the treatment of inflammation and novel insights into the management of IBD. 展开更多
关键词 Dietary flavonoids Inflammatory bowel disease Gut microbiota METABOLITES mechanisms
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Research progress on the physiological,biochemical and molecular regulatory mechanisms of fruit tree responses to high-temperature stress
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作者 Que Wang Yaqiong Wu +2 位作者 Wenlong Wu Lianfei Lyu Weilin Li 《Horticultural Plant Journal》 2025年第1期1-14,共14页
Fruit trees face various adverse environmental factors,such as extreme hydrothermal changes,soil salinization and low precipitation,leading to different types of stress.High temperature is one of the main factors affe... Fruit trees face various adverse environmental factors,such as extreme hydrothermal changes,soil salinization and low precipitation,leading to different types of stress.High temperature is one of the main factors affecting the growth of fruit trees,and an appropriate ambient temperature is a necessary condition for the normal growth and development of fruit trees.Since the 20th century,due to the intensification of the greenhouse effect and global warming,there has been a significant increase in the occurrence and duration of extreme hot weather in summer has been occurring frequently and for longer durations.Thus,the growth and production of fruit trees are affected by severe hightemperature stress.Therefore,this paper primarily summarized the impacts of high-temperature stress on fruit growth and development,flowering,fruiting,fruit setting and quality.It also discussed the physiological and biochemical responses of fruit trees to high-temperature stress,research progress on the molecular mechanisms and signal transduction pathways underlying fruit tree resistance to heat or high temperature,and research on the investigation of relevant metabolites of fruit trees under stress conditions.The future research directions were discussed,and prospects and potential difficulties were proposed to serve a reference for further investigation on the high-temperature tolerance of fruit trees. 展开更多
关键词 Heat shock Heat resistance Regulatory mechanisms MIRNA Fruit crop
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Dimethoxymethane carbonylation and disproportionation over extra-large pore zeolite ZEO-1:Reaction network and mechanism
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作者 Shaolei Gao Peng Lu +6 位作者 Liang Qi Yingli Wang Hua Li Mao Ye Valentin Valtchev Alexis T.Bell Zhongmin Liu 《Chinese Journal of Catalysis》 2025年第1期230-245,共16页
Methyl methoxyacetate(MMAc)and methyl formate(MF)can be produced directly by heterogeneous zeolite-catalyzed carbonylation and disproportionation of dimethoxymethane(DMM),with near 100%selectivity for each process.Des... Methyl methoxyacetate(MMAc)and methyl formate(MF)can be produced directly by heterogeneous zeolite-catalyzed carbonylation and disproportionation of dimethoxymethane(DMM),with near 100%selectivity for each process.Despite continuous research efforts,the insight into the reaction mechanism and kinetics theory are still in their nascent stage.In this study,ZEO-1 material,a zeolite with up to now the largest cages comprising 16×16-MRs,16×12-MRs,and 12×12-MRs,was explored for DMM carbonylation and disproportionation reactions.The rate of MMAc formation based on accessible Brönsted acid sites is 2.5 times higher for ZEO-1(Si/Al=21)relative to the previously investigated FAU(Si/Al=15),indicating the positive effect of spatial separation of active sites in ZEO-1 on catalytic activity.A higher MF formation rate is also observed over ZEO-1 with lower activation energy(79.94 vs.95.19 kJ/mol)compared with FAU(Si/Al=30).Two types of active sites are proposed within ZEO-1 zeolite:Site 1 located in large cages formed by 16×16-MRs and 16×12-MRs,which is active predominantly for MMAc formation,and Site 2 located in smaller cages for methyl formate/dimethyl ether formation.Kinetics investigation of DMM carbonylation over ZEO-1 exhibit a first-order dependence on CO partial pressure and a slightly inverse-order dependence on DMM partial pressure.The DMM disproportionation is nearly first-order dependence on DMM partial pressure,while it reveals a strongly inverse dependence with increasing CO partial pressure.Furthermore,ZEO-1 exhibits good catalytic stability,and almost no deactivation is observed during the more than 70 h test with high carbonylation selectivity of above 89%,due to the well-enhanced diffusion property demonstrated by intelligent-gravimetric analysis. 展开更多
关键词 Dimethoxymethane carbonylation Dimethoxymethane disproportionation ZEOLITE In-situ IR Kinetic Reaction mechanism
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