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Simultaneous determination of indole metabolites of tryptophan in rat feces by chemical labeling assisted liquid chromatography-tandem mass spectrometry

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Chinese Chemical Letters 2022年第11期33卷 4746-4749页

作者： qin-feng zhang Hua-Ming Xiao Jin-Tao Zhan Bi-feng Yuan Yu-Qi feng Department of Chemistry Wuhan UniversityWuhan 430072China School of Public Health Wuhan UniversityWuhan 430071China

As the connecting part of diet and host physiology,intestinal microbes can convert the ingested diet into a huge number of physiologically active small molecules.Indole metabolites of tryptophan are precursors or signal molecules for many biologically active substances,which are involved in serotonin and microbial catabolism pathways.To understand the influence of tryptophan metabolism in the intestinal environment on the neurological and immune systems at the molecular level,it is important to establish a high-coverage analytical method to comprehensively analyze the metabolites involved in tryptophan metabolism.However,due to a small molecular weight and poor response during mass spectrometry analysis,as well as weak retention on the reversed-phase chromatography,determination of indole metabolites of tryptophan is challenging.Here,we proposed a method for the simultaneous determination of 20 indole metabolites of tryptophan in a single run on reversed-phase chromatography by chemical labeling coupled to liquid chromatography-tandem mass spectrometry analysis.4-(Dimethylamino)benzaldehyde(DMAB)was used for the labeling of indole metabolites of tryptophan,which could significantly improve the detection sensitivities and retention of these metabolites on reversed-phase chromatography.With the developed method,we realized the sensitive detection and comprehensive analysis of 15 endogenous indole metabolites of tryptophan in rat feces samples with functional dyspepsia intervention by acupuncture.The developed method offers a useful tool for studying tryptophan metabolism-related diseases.

关键词： Chemical labeling Liquid chromatography-mass spectrometry Indole metabolites Tryptophan Rat feces

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Dynamical Behavior of SEIR-SVS Epidemic Models with Nonlinear Incidence and Vaccination

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Acta Mathematicae Applicatae Sinica 2022年第2期38卷 282-303页

作者： Xiao-mei feng Li-li LIU feng-qin zhang School of Mathematics and Informational Technology Yuncheng UniversityYuncheng 044000China School of Mathematics and Informational Sciences Shaanxi Normal UniversityXi'an 710062China Complex Systems Research Center Shanxi UniversityTaiyuan 030006China Shanxi Key Laboratory of Mathematical Techniques and Big Data Analysis on Disease Control and Prevention Shanxi UniversityTaiyuan 030006China

For some infectious diseases such as mumps,HBV,there is evidence showing that vaccinated individuals always lose their immunity at different rates depending on the inoculation time.In this paper,we propose an age-structured epidemic model using a step function to describe the rate at which vaccinated individuals lose immunity and reduce the age-structured epidemic model to the delay differential model.For the age-structured model,we consider the positivity,boundedness,and compactness of the semiflow and study global stability of equilibria by constructing appropriate Lyapunov functionals.Moreover,for the reduced delay differential equation model,we study the existence of the endemic equilibrium and prove the global stability of equilibria.Finally,some numerical simulations are provided to support our theoretical results and a brief discussion is given.

关键词： vaccination age-structured epidemic model delay differential equation model stability Lyapunov functional

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Fracture mechanism of inclusions in thick plate center under tensile loading

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1196-1209页

作者： Lei Hu Li-qin zhang feng Hu Guo-hong zhang Kuan Zheng Collaborative Innovation Center for Advanced Steels Wuhan University of Science and TechnologyWuhan430081HubeiChina Department of Applied Physics Wuhan University of Science and TechnologyWuhan430081HubeiChina Analysis and Testing Center Wuhan University of Science and TechnologyWuhan430081HubeiChina

Segregation of solute atoms in the center of thick plates of the tempered steel can cause an inhomogeneous structural transformation and generate micron-sized inclusions,which leads to lamellar tearing of thick plate and decreases the plasticity and toughness.The formation and fragmentation mechanisms of micron-sized inclusions,like MnS and(Nb,Ti)C,in the center of thick plates were investigated by using thermodynamic calculations,finite element simulations,and electron backscatter diffraction characterization techniques.The results show that micron-sized inclusions nucleate and grow in the liquid phase,and under tensile loading,they exhibit three fragmentation mechanisms.The local stress during the fragmentation of inclusions is lower than the critical fracture stress of adjacent grains,and phase boundaries can effectively impede crack propagation into the matrix.The existence of a low proportion of high-angle grain boundaries(58.1%)and high Kernel average misorientation value(0.534°)in the segregation band promotes inclusions fragmentation and crack propagation.The difference in crack initiation and propagation direction caused by the morphology of inclusions and physical properties,as well as different matrix arrest abilities,is the main reasons for the diversity of inclusion fragmentation.

关键词： Thick plate Inclusion Finite element simulation Critical fracture stress Fracture mechanism

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Effects and mechanisms of acupuncture on women related health

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Frontiers of Medicine 2024年第1期18卷 46-67页

作者： Huichao qin Jiaxing feng Xiaoke Wu Department of Reproductive Medicine Heilongjiang Provincial HospitalHarbin Institute of TechnologyHarbin150036China Department of Obstetrics and Gynecology First Affiliated HospitalHeilongjiang University of Chinese MedicineHarbin150040China

Globally,public health interventions have resulted in a 30-year increase in women’s life expectancy.However,women’s health has not increased when socioeconomic status is ignored.Women’s health has become a major public health concern,for those women from developing countries are still struggling with infectious and labor-related diseases,and their counterparts in developed countries are suffering from physical and psychological disorders.In recent years,complementary and alternative medicine has attracted wide attentions with regards to maintaining women’s health.Acupuncture,a crucial component of traditional Chinese medicine,has been used to treat many obstetric and gynecological diseases for thousands of years due to its analgesic and anti-inflammatory effects and its effects on stimulating the sympathetic/parasympathetic nervous system.To fully understand the mechanism through which acupuncture exerts its effects in these diseases would significantly extend the list of available interventions and would allow for more reasonable advice to be given to general practitioners.Therefore,by searching PubMed and CNKI regarding the use of acupuncture in treating obstetric and gynecological diseases,we aimed to summarize the proven evidence of using acupuncture in maintaining women’s health by considering both its effectiveness and the underlying mechanisms behind its effects.

关键词： acupuncture women health clinical efficacy mechanism

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Sensing-Assisted Accurate and Fast Beam Management for Cellular-Connected mmWave UAV Network

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China Communications 2024年第6期21卷 271-289页

作者： Cui Yanpeng zhang Qixun feng Zhiyong qin Wen Zhou Ying Wei Zhiqing zhang Ping School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China School of Computer Science Northwestern Polytechnical UniversityXi’an 710072China

Beam management,including initial access(IA)and beam tracking,is essential to the millimeter-wave Unmanned Aerial Vehicle(UAV)network.However,the conventional communicationonly and feedback-based schemes suffer a high delay and low accuracy of beam alignment,since they only enable the receiver to passively“hear”the information of the transmitter from the radio domain.This paper presents a novel sensing-assisted beam management approach,the first solution that fully utilizes the information from the visual domain to improve communication performance.We employ both integrated sensing and communication and computer vision techniques and design an extended Kalman filtering method for beam tracking and prediction.Besides,we also propose a novel dual identity association solution to distinguish multiple UAVs in dynamic environments.Real-world experiments and numerical results show that the proposed solution outperforms the conventional methods in IA delay,association accuracy,tracking error,and communication performance.

关键词： beam management integrated sensing and communication UAV communication

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Carbon-based materials with combined functions of thermal management and electromagnetic protection: Preparation, mechanisms, properties, and applications

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Nano Research 2024年第3期17卷 883-903页

作者： Junwei Yue Yiyu feng Mengmeng qin Wei feng School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin 300350China

The proliferation of high-power,highly informationized,and highly integrated electronic devices and weapons equipment has given rise to increasingly conspicuous issues about electromagnetic(EM)pollution and thermal accumulation.These issues,in turn,impose constraints on the performance of such equipment and jeopardize personnel safety.Carbon materials,owing to their diverse and modifiable structures,offer adjustable thermal and electric conductivity,rendering them highly promising for applications in fields such as thermal management and EM protection which have garnered extensive research and review.The pursuit of integrated device and equipment development has elevated the demand for multifunctional materials,prompting significant research into carbon-based composite materials that include both thermal management and EM protection functionalities.Notably,there are no relevant reviews on this topic at present.Consequently,this work consolidates research findings from recent years on carbon matrix composites exhibiting dual attributes of thermal management and EM protection.These attributes include thermally conductive electromagnetic interference(EMI)shielding materials,thermally insulating EMI shielding materials,thermally conductive EM wave(EMW)absorbing materials,and thermally insulating EMW absorbing materials.The paper elucidates the fundamental principles underpinning thermal conduction,thermal insulation,EMW absorbing,and EMI shielding.Additionally,it engages in discussions surrounding areas of contention,design strategies,and the functional properties of various material designs.Ultimately,the paper concludes by presenting the challenges encountered and potential research strategies about composites endowed with both thermal management and EM protection functionalities,while also envisaging the development of novel multifunctional EM protection materials.

关键词： carbon-based composites electromagnetic interference shielding microwave absorption thermal conduction thermal insulation

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The evolving views of hematopoiesis:from embryo to adulthood and from in vivo to in vitro

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Journal of Genetics and Genomics 2024年第1期51卷 3-15页

作者： Yifan zhang feng Liu Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology School of Life SciencesShandong UniversityQingdaoShandong 266237China State Key Laboratory of Membrane Biology Institute of ZoologyInstitute for Stem Cell and RegenerationUniversity of Chinese Academy of SciencesChinese Academy of SciencesBeijing 100101China

The hematopoietic system composed of hematopoietic stem and progenitor cells(HSPCs)and their differentiated lineages serves as an ideal model to uncover generic principles of cell fate transitions.From gastrulation onwards,there successively emerge primitive hematopoiesis(that produces specialized he-matopoietic cells),pro-definitive hematopoiesis(that produces lineage-restricted progenitor cells),and definitive hematopoiesis(that produces multipotent HSPCs).These nascent lineages develop in several transient hematopoietic sites and finally colonize into lifelong hematopoietic sites.The development and maintenance of hematopoietic lineages are orchestrated by cell-intrinsic gene regulatory networks and cell-extrinsic microenvironmental cues.Owing to the progressive methodology(e.g.,high-throughput lineage tracing and single-cell functional and omics analyses),our understanding of the developmental origin of hematopoietic lineages and functional properties of certain hematopoietic organs has been updated;meanwhile,new paradigms to characterize rare cell types,cell heterogeneity and its causes,and comprehensive regulatory landscapes have been provided.Here,we review the evolving views of HSPC biology during developmental and postnatal hematopoiesis.Moreover,we discuss recent advances in the in vitro induction and expansion of HSPCs,with a focus on the implications for clinical applications.

关键词： Hematopoietic stem and progenitor cell Developmental hematopoiesis Postnatal hematopoiesis In vitro hematopoiesis

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The infection kinetics and transmission potential of two Guaico Culex viruses in Culex quinquefasciatus mosquitoes

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Virologica Sinica 2024年第2期39卷 228-234页

作者： Ru-Yi Chen Teng Zhao Jing-Jing Guo feng Zhu Na-Na zhang Xiao-feng Li Hai-Tao Liu Fei Wang Yong-Qiang Deng Cheng-feng qin College of Bioscience and Bioengineering Jiangxi Agricultural UniversityNanchang330045China State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and EpidemiologyAMMSBeijing100071China School of Life Sciences Southwest Forestry UniversityKunming650224China

Guaico Culex virus(GCXV)is a newly identified segmented Jingmenvirus from Culex spp.mosquitoes in Central and South America.The genome of GCXV is composed of four or five single-stranded positive RNA segments.However,the infection kinetics and transmission capability of GCXV in mosquitoes remain unknown.In this study,we used reverse genetics to rescue two GCXVs(4S and 5S)that contained four and five RNA segments,respectively,in C6/36 cells.Further in vitro characterization revealed that the two GCXVs exhibited comparable replication kinetics,protein expression and viral titers.Importantly,GCXV RNAs were detected in the bodies,salivary glands,midguts and ovaries of Culex quinquefasciatus at 4–10 days after oral infection.In addition,two GCXVs can colonize Cx.quinquefasciatus eggs,resulting in positive rates of 15%–35%for the second gonotrophic cycle.In conclusion,our results demonstrated that GCXVs with four or five RNA segments can be detected in Cx.quinquefasciatus eggs during the first and second gonotrophic cycles after oral infection.

关键词： Guaico Culex virus(GCXV) Jingmenvirus Culex quinquefasciatus Vertical transmission

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Synergically regulated silver species and surface oxygen on manganese oxide for promoted activity of formaldehyde oxidation

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Journal of Environmental Sciences 2024年第4期138卷 709-718页

作者： Shuo Hu Jianghao zhang Xueyan Chen Xiaoxiao qin Jinshui Yao Changbin zhang School of Materials Science&Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Formaldehyde(HCHO)is a common indoor pollutant that is detrimental to human health.Its efficient removal has become an urgent demand to reduce the public health risk.In this work,Ag-MnO_(x)-based catalysts were prepared and activated under different atmosphere(i.e.,air,hydrogen(H_(2))and carbon monoxide(CO))for efficient oxidation of HCHO.The catalyst activated with CO(Ag/Mn-CO)displayed the highest activity among the tested samples with 90% conversion at 100℃ under a gas space velocity of 75,000 mL/(g_(cat)·hr).Complementary characterizations demonstrate that CO reduction treatment resulted in synergically regulated content of surface oxygen on support to adsorb/activate HCHO and size of Ag particle to dissociate oxygen to oxidize the adsorbed HCHO.In contrast,other catalysts lack for either abundant surface oxygen species or metallic silver with the appropriate particle size,so that the integrate activity is limited by one specific reaction step.This study contributes to elucidating the mechanisms regulating the oxidation activity of Ag-based catalysts.

关键词： HCHO oxidation Ag-MnO_(x)-based catalyst Activation condition Synergic regulation Surface oxygen Oxidized Ag

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METTL5 promotes gastric cancer progression via sphingomyelin metabolism

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1925-1946页

作者： Ya-Qiong zhang Jian Li Zhe qin De-Ming Li Fang-Zhou Ye Song-Hua Bei Xiao-Hong zhang Li feng Endoscopy Center Minhang Hospital Affiliated to Fudan UniversityShanghai 201100China

BACKGROUND The treatment of gastric cancer(GC)has caused an enormous social burden worldwide.Accumulating studies have reported that N6-methyladenosine(m6A)is closely related to tumor progression.METTL5 is a m6A methyltransferase that plays a pivotal role in maintaining the metabolic stability of cells.However,its aberrant regulation in GC has not been fully elucidated.AIM To excavate the role of METTL5 in the development of GC.METHODS METTL5 expression and clinicopathological characteristics were analyzed via The Cancer Genome Atlas dataset and further verified via immunohistochemistry,western blotting and real-time quantitative polymerase chain reaction in tissue microarrays and clinical samples.The tumor-promoting effect of METTL5 on HGC-27 and AGS cells was explored in vitro by Cell Counting Kit-8 assays,colony formation assays,scratch healing assays,transwell assays and flow cytometry.The tumor-promoting role of METTL5 in vivo was evaluated in a xenograft tumor model.The EpiQuik m6A RNA Methylation Quantification Kit was used for m6A quantification.Next,liquid chromatography-mass spectrometry was used to evaluate the association between METTL5 and sphingomyelin metabolism,which was confirmed by Enzyme-linked immunosorbent assay and rescue tests.In addition,we investigated whether METTL5 affects the sensitivity of GC cells to cisplatin via colony formation and transwell experiments.RESULTS Our research revealed substantial upregulation of METTL5,which suggested a poor prognosis of GC patients.Increased METTL5 expression indicated distant lymph node metastasis,advanced cancer stage and pathological grade.An increased level of METTL5 correlated with a high degree of m6A methylation.METTL5 markedly promotes the proliferation,migration,and invasion of GC cells in vitro.METTL5 also promotes the growth of GC in animal models.METTL5 knockdown resulted in significant changes in sphingomyelin metabolism,which implies that METTL5 may impact the development of GC via sphingomyelin metabolism.In addition,high METTL5 expr

关键词： Gastric cancer METTL5 Sphingomyelin metabolism Cisplatin

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