检索结果-南通市图书馆

A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第2期20卷 503-517页

作者： Qi Liu Jianye Xie Runxue Zhou Jin Deng Weihong Nie Shuwei Sun Haiping Wang Chunying Shi Department of Human Anatomy Histology and EmbryologySchool of Basic MedicineQingdao UniversityQingdaoShandong ProvinceChina Department of Neurology The Affiliated Hospital of Qingdao UniversityQingdaoShandong ProvinceChina Department of General Practice The Affiliated Hospital of Qingdao UniversityQingdaoShandong ProvinceChina

Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic ***,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in ***,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic *** metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ***,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel ***-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in *** results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor *** findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.

关键词： angiogenesis biomaterial blood-brain barrier cerebral ischemia/reperfusion injury control release drug delivery inflammation QK peptides matrix metalloproteinase-2 neuroprotection self-assembling nanofiber hydrogel

维普期刊数据库

Physiological mechanism underlying spikelet degeneration in rice

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2018年第7期17卷 1475-1481页

作者： WANG Zhi-qin ZHANG Wei-yang YANG Jian-chang key laboratory of Crop Genetics and Physiology of jiangsu province/Innovation Center for Modern Production Technology of Grain Crops of jiangsu province Yangzhou University

The phenomenon of degenerated spikelets is very common in cereals, and considered as a serious physiological defect and a main constraint to grain production. Understanding the physiological mechanism in which spikelet degeneration occurs would have great significance in enhancing yield potential in grain crops. Taking rice as an example, the paper reviewed the physiological mechanism underlying spikelet degeneration, with focus on the roles of phytohormones in regulating the process. There are several hypotheses for the spikelet degeneration, such as resource limitation, self-organization, and primigenic dominance. However, convincing evidences are not enough to support the assumptions. Phytohormones including auxins, cytokinins, gibberellins, abscisic acid, and ethylene are involved in regulating spikelet degeneration in cereals. The new phytohormones of brassinosteroids and polyamines have been observed to suppress spikelet degeneration in rice. The interactions among or between plant hormones may play a more important role in regulating spikelet degeneration. However, the information on such interactions is very limited. Some agronomic practices, especially proper water and nitrogen management, could reduce spikelet degeneration but the mechanism underlying remains unclear. Further research is needed to understand the cross-talk among/between phytohormones on spikelet degeneration, to reveal the physiological and molecular mechanism in which phytohormones and their interactions regulate the degeneration of spikelets, to exploit approaches to decrease spikelet degeneration and to elucidate their mechanism.

关键词： rice(Oryza safiva) spikelet degeneration phytohormones brassinosteroids polyamines

维普期刊数据库

Mechanism of water-evaporation-induced electricity beyond streaming potential

在线全文

学校读者我要写书评

暂无评论

Nano Research Energy 2024年第2期3卷 12-19页

作者： Sunmiao Fang Huan Lu Weicun Chu Wanlin Guo State key laboratory of Mechanics and Control of Mechanical Structures Key Laboratory for Intelligent Nano Materials and Devices of the Ministry of EducationNanjing University of Aeronautics and AstronauticsNanjing 210016China College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Institute for Frontier Science Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Since its first discovery in 2017,evaporation-induced electricity has attracted extensive attention and shown significant advantages in green energy *** the streaming potential-related electrokinetic effect has been intensively explored and widely recognized as the underlying mechanism,the role of coupling between water molecules and charge carriers in the material remains *** we show through carefully designed experiments that the streaming potential effect indeed plays a role but can only contribute about half to the total water-evaporation-induced voltage occurring within the partially-wetted region of the carbon black film where the solid-liquid-gas three-phase interface *** is also shown that water evaporation from carboxyl and amino-functionalized carbon black films produces opposite voltage *** first-principles calculations unveil that the adsorption of water molecules can lead to reversed charge transfer in the carboxyl and amino-functionalized carbon ***,an evaporation-driven charge transport mechanism is proposed for the induced electricity mediated by the coupling between water molecules and charge carriers in the *** results reveal the important role of direct interaction between water molecules and materials,deepening our understanding of the mechanism for evaporation-induced hydrovoltaic effect beyond streaming potential.

关键词： evaporation-induced electricity streaming potential hydrovoltaic effect charge transfer

Cascade reaction of 3-formylchromones:Highly selective synthesis of 4-oxo-3-(1H-pyrrol-3-yl)-4H-chromenes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Green Synthesis and Catalysis

Green Synthesis and Catalysis 2024年第2期5卷 94-101页

作者： Ying Lv Li Chen Xinghan Yun Kun Li Shengjiao Yan key laboratory of Medicinal Chemistry for Natural Resource(Yunnan University) Ministry of EducationSchool of Chemical Science and TechnologyYunnan UniversityKunming 650091China

A novel method for the preparation of highly functionalized 4-oxo-3-(1H-pyrrol-3-yl)-4H-chromenes(OPCMs)from 3-formylchromones andα-isocyanoacetates via an unprecedented three-component[1+1+3]cycloaddition reaction in one pot was *** three-component cascade reaction was enabled by refluxing a mixture of the substrates in 1,4-dioxane in the presence of Ag_(2)CO_(3) as a Lewis acid *** a result,a series of functionalized pyrroles(OPCMs,3),was prepared regioselectively and in high yields(80%-88%)through the formation of three *** protocol can be used in the synthesis of OPCMs rather than through conventional,multi-step reactions and is suitable for both combinatorial and parallel syntheses of pyrroles.

关键词： 4-Oxo-3-(1H-pyrrol-3-yl)-4H-chromenes Three-component Cascade reaction [1+1+3]cycloaddition 3-Formylchromones

Britanin–a beacon of hope against gastrointestinal tumors?

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Oncology 2024年第4期15卷 523-530页

作者： Agnieszka Kajdanek Damian Kołat Lin-Yong Zhao Mateusz Kciuk Zbigniew Pasieka Żaneta Kałuzińska-Kołat Department of Biomedicine and Experimental Surgery Medical University of LodzLodz 90-136LodzkiePoland Department of Functional Genomics Medical University of LodzLodz 90-752LodzkiePoland Department of General Surgery&laboratory of Gastric Cancer State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy and Cancer CenterWest China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Gastric Cancer Center West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of molecular Biotechnology and Genetics University of LodzLodz 90-237LodzkiePoland

Britanin is a bioactive sesquiterpene lactone known for its potent anti-inflammatory and anti-oxidant *** also exhibits significant anti-tumor activity,suppressing tumor growth in vitro and in *** current body of research on Britanin includes thirty papers predominantly related to neoplasms,the majority of which are gastrointestinal tumors that have not been summarized *** drive academic debate,the present paper reviews the available research on Britanin in gastrointestinal *** also outlines novel research directions using data not directly concerned with the digestive system,but which could be adopted in future gastrointestinal *** was found to counteract liver,colorectal,pancreatic,and gastric tumors,by regulating proliferation,apoptosis,autophagy,immune response,migration,and *** confirmed in pancreatic,gastric,and liver cancer,its most commonly noted molecular effects include nuclear factor kappa B and B-cell lymphoma 2 downregulation,as well as Bcl-2-associated X protein ***,it has been found to induce the Akt kinase and Forkhead box O1 axis,activate the AMP-activated protein kinase pathway,elevate interleukin-2 and peroxisome proliferator-activated receptor-γlevels,reduce interleukin-10,as well as downregulate matrix metalloproteinase-9,Twist family bHLH transcription factor 1,and *** also inhibits Myc–HIF1αinteraction and programmed death ligand 1 transcription by interrupting the Ras/RAF/MEK/ERK pathway and mTOR/P70S6K/4EBP1 *** research should aim to unravel the link between Britanin and acetylcholinesterase,mast cells,osteolysis,and ischemia,as compelling data have been provided by studies outside the gastrointestinal *** the cytotoxicity of Britanin on noncancerous cells is significantly lower than that on tumor cells,while still being effective against the latter,further in-depth studies with the use of animal models are *** compound exhi

关键词： Britanin Sesquiterpene lactones Chemotherapeutics Gastrointestinal tumors In vitro In vivo

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

Rational design of a highly active N-glycosyltransferase mutant using fragment replacement approach

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Engineering Microbiology 2024年第1期4卷 10-17页

作者： Jiangyu Yang Kun Li Yongheng Rong Zhaoxi Liu Xiaoyu Liu Yue Yu Wenjing Shi Yun Kong Min Chen State key laboratory of Microbial Technology Shandong UniversityQingdao 266237China National Glycoengineering Research Center Shandong UniversityQingdao 266237China

The modularity of carbohydrate-active enzymes facilitates that enzymes with different functions have similar ***,because of the complex structure of the enzyme active sites and the epistatic effects of various mutations on enzyme activity,it is difficult to design enzymes with multiple mutation sites using conventional *** this study,we designed multi-point mutants by fragment replacement in the donor-acceptor binding pocket of Actinobacillus pleuropneumoniae N-glycosyltransferase(ApNGT)to obtain novel *** fragments were selected from a customized glycosyltransferase *** stability and substrate-binding energy of the three fragment replacement mutants were calculated in comparison with wild-type ApNGT,and mutants with top-ranking stability and middle-ranking substrate-binding energy were chosen for priority experimental *** found that a mutant called F13,which increased the glycosylation efficiency of the natural substrate by 1.44 times,the relative conversion of UDP-galactose by 14.2 times,and the relative conversion of UDP-xylose from almost 0 to 78.6%.Most importantly,F13 mutant acquired an entirely new property,the ability to utilize UDP-glucuronic *** one hand,this work shows that replacing similar fragments in the donoracceptor binding pocket of the enzyme might provide new ideas for designing mutants with new properties;on the other hand,F13 mutant is expected to play an important role in targeted drug delivery.

关键词： N-glycosyltransferase Computational design Glycoprotein Fragment replacement GT41

Accurate estimation of 6-Do F tooth pose in 3D intraoral scans for dental applications using deep learning

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Information Technology & Electronic Engineering 2024年第9期25卷 1240-1249页

作者： Wanghui DING Kaiwei SUN Mengfei YU Hangzheng LIN Yang FENG Jianhua LI Zuozhu LIU Stomatology Hospital School of StomatologyZhejiang University School of MedicineZhejiang Provincial Clinical Research Center for Oral DiseasesKey Laboratory of Oral Biomedical Research of Zhejiang ProvinceCancer Center of Zhejiang UniversityEngineering Research Center of Oral Biomaterials and Devices of Zhejiang ProvinceHangzhou 310000China Zhejiang UniversityUniversity oflinois at Urbana-Champaign Institute Zhejiang UniversityHaining 34400China Angel Align Inc. ShanghaiShanghai 200433China Hangzhou Dental Hospital Hangzhou 310006China

A critical step in digital dentistry is to accurately and automatically characterize the orientation and position of individual teeth,which can subsequently be used for treatment planning and simulation in orthodontic tooth *** problem remains challenging because the geometric features of different teeth are complicated and vary significantly,while a reliable large-scale dataset is yet to be *** this paper we propose a novel method for automatic tooth orientation estimation by formulating it as a six-degree-of-freedom(6-Do F)tooth pose estimation *** each tooth as a threedimensional(3D)point cloud,we design a deep neural network with a feature extractor backbone and a two-branch estimation head for tooth pose *** model,trained with a novel loss function on the newly collected large-scale dataset(10393 patients with 280611 intraoral tooth scans),achieves an average Euler angle error of only 4.780°–5.979°and a translation L1 error of 0.663 mm on a hold-out set of 2598 patients(77870 teeth).Comprehensive experiments show that 98.29%of the estimations produce a mean angle error of less than 15°,which is acceptable for many clinical and industrial applications.

关键词： Artificial intelligence Digital dentistry Deep learning Orthodontics Tooth pose Neural network

维普期刊数据库

Performance analysis of an R290 vapor-injection heat pump system for electric vehicles in cold regions

在线全文

学校读者我要写书评

暂无评论

Science China Technological Sciences 2024年

作者： YANG YunChun SHAO WenCong YANG TianYang ZOU HuiMing TIAN ChangQing Technical Institute of Physics and Chemistry Key Laboratory of Cryogenic Science and Technology Chinese Academy of Sciences University of Chinese Academy of Sciences

High-performance automotive thermal management systems with environment-friendly refrigerants are essential for achieving carbon peaking and carbon neutrality goals. In this study, an R290 vapor-injection heat pump system for electric vehicles is developed and experimentally investigated. The effects of refrigerant charge mass, injection pressure, and in-cabin air temperature are analyzed in ambient temperatures from-30℃ to 0℃. The results show that the vapor-injection system can increase the coefficient of performance (COP) and heating capacity by 14.3%and 15.9%at 0℃/20℃ (ambient/in-cabin temperature)compared with the basic system, and this increase becomes more significant at-20℃/20℃ with improvements of 32.5%and38.1%, respectively. At a lower ambient temperature of-20℃, increasing refrigerant charge mass contributes to a more pronounced increase in heating capacity than at 0℃, which results from the more significant increase in injection mass flow. The optimal COP at various injection pressures are 2.07 and 1.63 at 0℃ and-20℃ ambient temperatures, corresponding to the relative injection pressures of 0.60 and 0.57, and the injection flow ratios of 0.23 and 0.29, respectively. At-30℃/0℃, a COP of1.69 can be achieved.

关键词：