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Pyridapeptides F–I,cyclohexapeptides from marine sponge-derived Streptomyces ***-4539

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Chinese Chemical Letters 2024年第7期35卷 341-344页

作者： Shuige Zhao Pengcheng Yan Peipei liu Haishan liu ning li Peng Fu Weiming Zhu Key Laboratory of Marine Drugs Ministry of Education of ChinaSchool of Medicine and PharmacyOcean University of ChinaQingdao 266003China Key Laboratory for Marine Drugs and Bioproducts Laoshan LaboratoryQingdao 266237China School of Biological Science and Technology University of JinanJi'nan 250022China Key Laboratory for Biosensors of Shandong Province Biology InstituteQilu University of TechnologyJi'nan 250103China

Four new cyclohexapeptides,pyridapeptides F–I(1–4),were isolated from the fermentation broth of marine sponge-derived Streptomyces *** pyridapeptides F–H(1–3)are composed ofβ-hydroxyleucine,alanine,O-methylthreonine,hexahydropyridazine-3-carboxylic acid,5-hydroxytetrahydropyridazine-3-carboxylic acid,and(2S,3R,4E,6E)-2-amino-3–hydroxy-4,6-dienoic acid *** I(4)contains(2S,3R,4E,6E)-2-amino-3–hydroxy-8-methylnona-4,6-dienoic acid residue and a very rare glycose residue,*** structures were determined based on spectroscopic analysis and chemical *** G–I(2–4)have the 2,3,6-trideoxyhexose units glycosylated at theγ-OH-TPDA residue,displayed significant antiproliferative activity against four(PC9,MKN45,Hep G2,K562)or two(PC9,MKN45)human cancer cell lines.

关键词： Marine microorganism Streptomyces Cyclopeptide glycosides Pyridapeptides Antiproliferative activity

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Theoretical Exploration of Alloying Effects on Stabilities and Mechanical Properties ofγʹPhase in Novel Co–Al–Nb-Base Superalloys

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1238-1248页

作者： Guan-Cheng Gu Zhao-Jing Han Ze-Yu Chen Zhao-Xuan li Sheng-Bao Xia Zheng-ning li Hua Jin Wei-Wei Xu Xing-Jun liu Shenzhen Research Institute of Xiamen University School of Aerospace EngineeringXiamen UniversityXiamen361005China Institute of Materials Genome and Big Data Harbin Institute of TechnologyShenzhen518055China

The new developedγ/γʹCo–Al–Nb-base alloys show great potentials as high-temperature ***,finding appropriate compositions to improve performance of alloys still poses a great challenge to the development of Co–Al–Nb-base *** by the lack of alloying effects on fundamental properties of criticalγʹphase,we systematically performed a theoretical investigation on the effect of alloying elements TM(TM:Ti,V,Cr,Zr,Mo,Ta,W,Re,and Ru)on phase stabilities and mechanical properties of L1_(2)-typeγʹ(Co,Ni)_(3)(Al,Nb).By analyzing the stability ofγʹphase with respect to its competitive B2 and D0_(19) phases,the results shown that Ti,V,and Cr enhance the L1_(2) stability and widen the L1_(2)–D0_(19) energy barrier,in which V yields the maximum *** analysis of electronic structure indicated that the alternation of valence electrons at fermi level would be the atomic origin for doping TM inγʹ*** calculated results of mechanical properties shown that V and Cr are expected to be optimal dopant for enhancing the strength and the ductility ofγʹ*** addition of Ta is also beneficial for enhancing the strength at the slight expense of ductility ofγʹ*** drawing the mechanical maps,the preferred composition range for the phases with desired properties is roughly demarcated in theory for the multi-addition of V/Cr and V/Ta inγʹ*** findings would be useful for optimizing the performance of novelγ/γʹCo–Al–Nb-base superalloys.

关键词： Co-Al-Nb-base superalloys γ/γʹdual-phase Phase stability Mechanical properties First-principle methods

Performance Analysis of Spatial Modulation Aided UAV Communication Systems in Cooperative Relay Networks

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Chinese Journal of Electronics 2024年

作者： Xiangbin YU Mingfeng XIE ning li Cuimin PAN College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics State Key Laboratory of Millimeter Waves Southeast University

In this paper, by introducing the spatial modulation(SM) scheme into the unmanned aerial vehicle(UAV) relaying system, a SM-aided UAV(SM-UAV) cooperative relay network is presented. The performance of the SM-UAV relay network is investigated over Nakagami-m fading channels, where the UAV remains stationary over a given area. According to the performance analysis, using the amplify-and-forward(AF) protocol, the effective signalto-noise ratio(SNR) and the corresponding probability density function and moment generating function are, respectively, derived. With these results, the average bit error rate(BER) is further deduced, and resultant approximate closed-form expression is achieved. Based on the approximate BER, we derive the asymptotic BER to characterize the error performance of the system at high SNR. With this asymptotic BER, the diversity gain of the system is derived, and the resulting diversity order is attained. Simulation results illustrate the effectiveness of the performance analysis. Namely, approximate BER has the value close to the simulated one, and asymptotic BER can match the corresponding simulation well at high SNR. Thus, the BER performance of the system can be effectively assessed in theory, and conventional simulation will be avoided. Besides, the impacts of the antenna number, modulation order,fading parameter and UAV position on the system performance are also analyzed. The results indicate that the BER performance is increased with the increases of Nakagami parameter m and/or receive antenna and/or the decrease of modulation order.

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Treatment of hemolymphangioma by robotic surgery: A case report

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 596-600页

作者： Tian-ning li Yan-Hong liu Jia Zhao Hong Mu Lei Cao Department of Clinical Lab Tianjin First Central HospitalTianjin 300000China Nankai University Tianjin Union Medical CenterTianjin 300000China Tianjin Medical University Tianjin First Center HospitalTianjin 300000China

BACKGROUND Hemolymphangioma of the jejunum is rare and lacks clinical specificity,and can manifest as gastrointestinal bleeding,abdominal pain,and intestinal *** tomography,magnetic resonance imaging,and other examinations show certain characteristics of the disease,but lack *** capsule endoscopy and enteroscopy make up for this deficiency,the diagnosis also still re-quires *** SUMMARY A male patient was admitted to the hospital due to abdominal distension and abdominal pain,but a specific diagnosis by computed tomography examination was not *** resection of the small intestine was performed by robotic surgery,and postoperative pathological biopsy confirmed the diagnosis of *** recurrence in the follow-up examination was *** Robotic surgery is an effective way to treat hemolymphangioma through minima-lly invasive techniques under the concept of rapid rehabilitation.

关键词： Hemolymphangioma Enteroscopy Robotic surgery Rehabilitation Case report

Pathological diagnosis and immunohistochemical analysis of giant retrosternal goiter in the elderly: A case report

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World Journal of Clinical Cases 2024年第3期12卷 643-649页

作者： Yong-Chang Meng liu-Sheng Wu ning li Hong-Wei li Jing Zhao Jun Yan Xiao-Qiang li Peng li Jiang-Qi Wei Department of Cardiothoracic Surgery Xinxiang First People's HospitalXinxiang 453000Henan ProvinceChina School of Clinical Medicine Tsinghua UniversityBeijing 100084China Graduate School Qinghai UniversityXining 810016Qinghai ProvinceChina Department of Pathology Xinxiang First People's HospitalXinxiang 453000Henan ProvinceChina Department of Thoracic Surgery Peking University Shenzhen HospitalShenzhen 518036Guangdong ProvinceChina

BACKGROUND Elderly giant retrosternal thyroid goiter is a rare yet significant medical condition,often presenting clinical symptoms that can be confused with other diseases,posing diagnostic and therapeutic *** study aims to delve into the characteristics and potential mechanisms of this ailment through pathological diagnosis and immunohistochemical analysis,providing clinicians with more precise diagnostic and treatment strategies.A 77-year-old male,was admitted to hospital with the chief complaint of finding a goiter in the semilunar month during physical examination,accompanied by *** protruding into the superior mediastinum,the adjacent structure was compressed,the trachea was compressed to the right,and the local lumen was slightly *** patient was diagnosed with giant retrosternal *** dyspnea caused by trachea compression,our department planned to perform giant retrosternal *** results:Tg(+),TTF-1(+),Calcitonin(CT)(I),Ki-67(+,about 20%),CD34(-).Retrosternal goiter means that more than 50%of the volume of the thyroid gland is below the upper margin of the *** retrosternal goiter disease is a relatively rare disease,once the disease is diagnosed,it should be timely surgical treatment,and the treatment is more difficult,the need for professional medical team for comprehensive *** The imaging manifestations of giant retrosternal goiter are atypical,histomorphology and immunohistochemistry can assist in its *** article reviews the relevant literature of giant retrosternal goiter immunohisto-chemistry and shows that giant retrosternal goiter is positive for Tg,TTF-1,and Ki-67.

关键词： Giant retrosternal goiter Pathology Immunohistochemistry Case report

Mitochondrial carrier homolog 2 increases malignant phenotype of human gastric epithelial cells and promotes proliferation,invasion,and migration of gastric cancer cells

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 991-1005页

作者： Jing-Wen Zhang ling-Yan Huang Ya-ning li Ying Tian Jia Yu Xiao-Fei Wang School of Basic Medical Science NHC Key Laboratory of Metabolic Cardiovascular Diseases ResearchNingxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina Department of Pathology General Hospital of Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina School of Clinical Medicine Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina Department of Pathology North China University of Science and Technology Affiliated HospitalTangshan 063000Hebei ProvinceChin

BACKGROUND The precise role of mitochondrial carrier homolog 2(MTCH2)in promoting malignancy in gastric mucosal cells and its involvement in gastric cancer cell metastasis have not been fully *** To determine the role of MTCH2 in gastric *** We collected 65 samples of poorly differentiated gastric cancer tissue and adjacent tissues,constructed MTCH2-overexpressing and MTCH2-knockdown cell models,and evaluated the proliferation,migration,and invasion of human gastric epithelial cells(GES-1)and human gastric cancer cells(AGS)*** mito-chondrial membrane potential(MMP),mitochondrial permeability transformation pore(mPTP)and ATP fluorescence probe were used to detect mitochondrial *** function and ATP synthase protein levels were detected via Western *** The expression of MTCH2 and ATP2A2 in gastric cancer tissues was significantly greater than that in adjacent *** of MTCH2 promoted colony formation,invasion,migration,MMP expression and ATP production in GES-1 and AGS cells while upregulating ATP2A2 expression and inhibiting cell apoptosis;knockdown of MTCH2 had the opposite effect,promoting overactivation of the mPTP and promoting *** MTCH2 can increase the malignant phenotype of GES-1 cells and promote the proliferation,invasion,and migration of gastric cancer cells by regulating mitochondrial function,providing a basis for targeted therapy for gastric cancer cells.

关键词： Gastric cancer Mitochondrial carrier homolog 2 ATP synthase ATP2A2 Mitochondrial permeability transformation pore

SiO_(2) Induces Iron Overload and Ferroptosis in Cardiomyocytes in a Silicosis Mouse Model

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Biomedical and Environmental Sciences 2024年第6期37卷 617-627页

作者： Yongheng Wang ning li Yi Guan Tong li Yuxiu Zhang Hong Cao Zhihua Yu Zhiheng li Shuoyan li Jiahao Hu Wenxin Zhou Sisi Qin Shuang li Sanqiao Yao School of Public Health North China University of Science and TechnologyTangshan 063210HebeiChina Hebei Key Laboratory of Occupational Health and Safety for Coal Industry North China University of Science and TechnologyTangshan 063210HebeiChina Occupational Disease Prevention and Control Institute of Jinneng Holding Coal Industry Group Co. LtdDatong 037001ShanxiChina China Pingmei Shenma Group Occupational Disease Prevention and Control Hospital Pingdingshan 467000HenanChina School of Public Health Xinxiang Medical UniversityXinxiang 453003HenanChina

Objective The aim of this study was to explore the role and mechanism of ferroptosis in SiO_(2)-induced cardiac injury using a mouse *** Male C57BL/6 mice were intratracheally instilled with SiO_(2) to create a silicosis ***-1(Fer-1)and deferoxamine(DFO)were used to suppress *** biomarkers,oxidative stress markers,histopathology,iron content,and the expression of ferroptosis-related proteins were *** SiO_(2) altered serum cardiac injury biomarkers,oxidative stress,iron accumulation,and ferroptosis markers in myocardial ***-1 and DFO reduced lipid peroxidation and iron overload,and alleviated SiO_(2)-induced mitochondrial damage and myocardial ***_(2) inhibited Nuclear factor erythroid 2-related factor 2(Nrf2)and its downstream antioxidant genes,while Fer-1 more potently reactivated Nrf2 compared to *** Iron overload-induced ferroptosis contributes to SiO_(2)-induced cardiac *** ferroptosis by reducing iron accumulation or inhibiting lipid peroxidation protects against SiO_(2) cardiotoxicity,potentially via modulation of the Nrf2 pathway.

关键词： SiO_(2) exposure Iron overload Ferroptosis Cardiac injury Nrf2

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Combined use of fly ash and silica to prevent the long-term strength retrogression of oil well cement set and cured at HPHT conditions

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Petroleum Science 2024年第2期21卷 1122-1134页

作者： Guo-Dong Cheng Xue-Yu Pang Jin-Sheng Sun Zheng-Song Qiu Chuang-Chuang Wang Jian-Kun Qin ning li School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina Oil and Gas Engineering Research Institute(Tarim Oilfield Company) China National Petroleum CorporationTarim841000XinjiangChina

The long-term strength retrogression of silica-enriched oil well cement poses a significant threat to wellbore integrity in deep and ultra-deep wells, which is a major obstacle for deep petroleum and geothermal energy development. Previous attempts to address this problem has been unsatisfactory because they can only reduce the strength decline rate. This study presents a new solution to this problem by incorporating fly ash to the traditional silica-cement systems. The influences of fly ash and silica on the strength retrogression behavior of oil well cement systems directly set and cured under the condition of 200°C and 50 MPa are investigated. Test results indicate that the slurries containing only silica or fly ash experience severe strength retrogression from 2 to 30 d curing, while the slurries containing both fly ash and silica experience strength enhancement from 2 to 90 d. The strength test results are corroborated by further evidences from permeability tests as well as microstructure analysis of set cement. Composition of set cement evaluated by quantitative X-ray diffraction analyses with partial or no known crystal structure(PONKCS) method and thermogravimetry analyses revealed that the conversion of amorphous C-(A)-S-H to crystalline phases is the primary cause of long-term strength *** addition of fly ash can reduce the initial amount of C-(A)-S-H in the set cement, and its combined use with silica can prevent the crystallization of C-(A)-S-H, which is believed to be the working mechanism of this new admixture in improving long-term strength stability of oil well cement systems.

关键词： Fly ash Long-term strength retrogression High temperature Quantitative X-ray diffraction(QXRD) Partial or no known crystal structure(PONKCS)

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Reynosin protects neuronal cells from microglial neuroinflammation by suppressing NLRP3 inflammasome activation mediated by NADPH oxidase

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Chinese Journal of Natural Medicines 2024年第6期22卷 486-500页

作者： YANG Yanqiu CHE Yue FANG Mingxia YAO Xiaohu ZHOU Di WANG Feng CHEN Gang liANG Dong li ning HOU Yue Key Laboratory of Bioresource Research and Development of liaoning Province College of Life and Health SciencesNorth-eastern UniversityShenyang 110000China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Key Laboratory of Data Analytics and Optimization for Smart IndustryMinistry of EducationNortheastern UniversityShenyang 110000China School of Traditional Chinese Materia Medica Key Laboratory of Innovative Traditional Chinese Medicine for Major Chronic Diseases of Liaoning provinceKey Laboratory for TCM Material Basis Study and Innovative Drug Development of Shenyang CityShenyang Pharmaceutical UniversityShenyang 110000China State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541000China

Neuroinflammation,mediated by the nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing-3(NLRP3)inflammasome,is a significant contributor to the pathogenesis of neurodegenerative diseases(NDDs).Reynos-in,a natural sesquiterpene lactone(SL),exhibits a broad spectrum of pharmacological effects,suggesting its potential therapeutic ***,the effects and mechanism of reynosin on neuroinflammation remain *** current study explores the effects and mechanisms of reynosin on neuroinflammation using mice and BV-2 microglial cells treated with lipopolysaccharide(LPS).Our findings reveal that reynosin effectively reduces microglial inflammation in vitro,as demonstrated by decreased CD11b expression and lowered interleukin-1 beta(IL-1β)and interleukin-18(IL-18)mRNA and protein ***,in vivo,results showed a re-duction in the number of Iba-1 positive cells and alleviation of morphological alterations,alongside decreased expressions of IL-1βand *** analysis indicates that reynosin inhibits NLRP3 inflammasome activation,evidenced by reduced transcription of NLRP3 and caspase-1,diminished NLRP3 protein expression,inhibited apoptosis-associated speck-like protein containing a CARD(ASC)oli-gomerization,and decreased caspase-1 ***,reynosin curtailed the activation of nicotinamide adenine dinuc-leotide phosphate(NADPH)oxidase,demonstrated by reduced NADP^(+)and NADPH levels,downregulation of gp91^(phox) mRNA,pro-tein expression,suppression of p47^(phox) expression and translocation to the ***,reynosin exhibited a neuroprotective effect against microglial inflammation in vivo and in *** collective findings underscore reynosin’s capacity to mitigate mi-croglial inflammation by inhibiting the NLRP3 inflammasome,thus highlighting its potential as a therapeutic agent for managing neuroinflammation.

关键词： Microglia NLRP3 inflammasome Reactive oxygen species NADPH oxidase Neuron Reynosin