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The clinical impact of bacterial biofilms

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international Journal of Oral Science 2011年第2期3卷 55-65页

作者： Niels Hoiby Oana Ciofu Helle Krogh Johansen Zhi-jun Song Claus Moser Peter Ostrup Jenser Soren Molin Michael Givskov Tim Tolker-Nieisen Thomas Bjamsholt Department of Clinical Microbiology Rigshospitalet Institute for international Health Medical Microbiology and Immunology BloScience and Technology Biocentrum Danish Technical University

Bacteria survive in nature by forming biofilms on surfaces and probably most, if not all, bacteria （and fungi） are capable of forming biofilms. A biofilm is a structured consortium of bacteria embedded in a self-produced polymer matrix consisting of polysaccharide, protein and extracellular DNA. Bacterial biofilms are resistant to antibiotics, disinfectant chemicals and to phagocytosis and other components of the innate and adaptive inflammatory defense system of the body. It is known, for example, that persistence of staphylococcal infections related to foreign bodies is due to biofilm formation. Likewise, chronic Pseudomonas aeruginosa lung infections in cystic fibrosis patients are caused by biofilm growing mucoid strains. Gradients of nutrients and oxygen exist from the top to the bottom of biofilms and the bacterial cells located in nutrient poor areas have decreased metabolic activity and increased doubling times. These more or less dormant cells are therefore responsible for some of the tolerance to antibiotics. Biofilm growth is associated with an increased level of mutations. Bacteria in biofilms communicate by means of molecules, which activates certain genes responsible for production of virulence factors and, to some extent, biofilm structure. This phenomenon is called quorum sensing and depends upon the concentration of the quorum sensing molecules in a certain niche, which depends on the number of the bacteria. Biofilms can be prevented by antibiotic prophylaxis or early aggressive antibiotic therapy and they can be treated by chronic suppressive antibiotic therapy. Promising strategies may include the use of compounds which can dissolve the biofilm matrix and quorum sensing inhibitors, which increases biofilm susceptibility to antibiotics and phagocytosis.

关键词： bacterial biofilm biofilm infection antibiotic resistance quorum sensing

Comparison of electronic structure between monolayer silicenes on Ag(111)

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Chinese Physics B 2015年第8期24卷 120-124页

作者： Chun-Liang Lin Ryuichi Arafune Maki Kawai Noriaki Takagi Department of Advanced Materials Science Graduate School of Frontier ScienceThe University of Tokyo international Center for Materials Nanoarchitectonics (WPI-MANA) National Institute for Materials Science

√√The electronic structures of monolayer silicenes(4 × 4 and■ ×■R13.9o) grown on Ag(111) surface are studied by scanning tunneling spectroscopy(STS) and density functional theory(DFT) calculations. While both phases have similar electronic structures around the Fermi level, significant differences are observed in the higher energy unoccupied *** DFT calculations show that the contributions of Si 3pz orbitals to the unoccupied states are different because of their different buckled configurations.

关键词： silicene electronic structure STM DFT

Hydrogen sulfide-induced post-translational modification as a potential drug target

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Genes & Diseases 2023年第5期10卷 1870-1882页

作者： Hao-Jie Chen Lei Qian Ke Li Yang-Zhe Qin Jing-Jing Zhou Xin-Ying Ji Dong-Dong Wu School of Basic Medical Sciences Henan UniversityKaifengHenan 475004China Henan international Joint Laboratory for Nuclear Protein Regulation Henan UniversityKaifengHenan 475004China Kaifeng Key Laboratory of Infection and Biological Safety School of Basic Medical SciencesHenan UniversityKaifengHenan 475004China School of Stomatology Henan UniversityKaifengHenan 475004China

Hydrogen sulfide (H_(2)S) is one of the three known gas signal transducers, and since its potential physiological role was reported, the literature on H_(2)S has been increasing. H_(2)S is involved in processes such as vasodilation, neurotransmission, angiogenesis, inflammation, and the prevention of ischemia-reperfusion injury, and its mechanism remains to be further studied. At present, the role of post-translational processing of proteins has been considered as a possible mechanism for the involvement of H_(2)S in a variety of physiological processes. Current studies have shown that H_(2)S is involved in S-sulfhydration, phosphorylation, and S-nitrosylation of proteins, etc. This paper focuses on the effects of protein modification involving H_(2)S on physiological and pathological processes, looking forward to providing guidance for subsequent research.

关键词： Hydrogen sulfide Modification Phosphorylation S-nitrosylation S-sulfhydration

Lipid Metabolism: Critical Roles in Male Fertility and Other Aspects of Reproductive Development in Plants

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Molecular Plant 2020年第7期13卷 955-983页

作者： Xiangyuan Wan Suowei Wu Ziwen Li Xueli An Youhui Tian Zhongzhi international Institute of Agricultural Biosciences Biology and Agriculture Research CenterUniversity of Science and Technology BeijingBeijing 100024China Beijing Engineering Laboratory of Main Crop Bio-Tech Breeding Beijing International Science and Technology Cooperation Base of Bio-Tech BreedingBeijing Solidwill Sci-Tech Co.Ltd.Beijing 100192China

Fatty acids and their derivatives are essential building blocks for anther cuticle and pollen wall *** of lipid metabolism during anther and pollen development often leads to genic male sterility(GMS).To date,many lipid metabolism-related GMS genes that are involved in the formation of anther cuticle,pollen wall,and subcellular organelle membranes in anther wall layers have been identified and *** this review,we summarize recent progress on characterizing lipid metabolism-related genes and their roles in male fertility and other aspects of reproductive development in *** the basis of cloned GMS genes controlling biosynthesis and transport of anther cutin,wax,sporopollenin,and tryphine\r\Arabidopsis,rice,and maize as well as other plant species,updated lipid metabolic networks underlying anther cuticle development and pollen wall formation were *** bioinformatics analysis of anther RNA-sequencing datasets from three maize inbred lines(Oh43,W23,and B73),a total of 125 novel lipid metabolism-related genes putatively involved in male fertility in maize were ***,we discuss the pathways regulating lipid metabolism-related GMS genes at the transcriptional and post-transcriptional ***,we highlight recent findings on lipid metabolism-related genes and their roles in other aspects of plant reproductive development.A comprehensive understanding of lipid metabolism,genes involved,and their roles in plant reproductive development will facilitate the application of lipid metabolism-related genes in gene editing,haploid and callus induction,molecular breeding and hybrid seed production in crops.

关键词： lipid metabolism genic male sterility(GMS) anther cuticle pollen wall plant reproductive development

An Efficient Breast Cancer Detection Framework for Medical Diagnosis Applications

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Computers, Materials & Continua 2022年第1期70卷 1315-1334页

作者： Naglaa F.Soliman Naglaa S.Ali Mahmoud I.Aly Abeer D.Algarni Walid El-Shafai Fathi E.Abd El-Samie Department of Information Technology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh84428Saudi Arabia Department of Electronics and Communications Faculty of EngineeringZagazig UniversityZagazig44519Egypt international Academy for Engineering and Media Science October CityEgypt Department of Electronics and Electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt

Breast cancer is themost common type of cancer,and it is the reason for cancer death toll in women in recent *** diagnosis is essential to handle breast cancer patients for treatment at the right *** with mammography is the preferred examination for breast cancer,as it is available worldwide and ***-Aided Detection(CAD)systems are used to analyze medical images to detect breast cancer,*** death rate of cancer patients has decreased by detecting tumors early and having appropriate treatment after *** of mammogram images has four main steps:pre-processing,segmentation of the region of interest,feature extraction and classification of the images into normal or abnormal *** paper presents an efficient framework for processing of mammogram images and introduces an algorithm for segmentation of the images to detect *** pre-processing step of mammogram images includes removal of digitization noise using a 2D median filter,removal of artifacts using morphological operations,and contrast enhancement using a fuzzy enhancement *** proposed fuzzy image enhancement technique is analyzed and compared with conventional techniques based on an Enhancement Measure(EME)and local contrast *** comparison shows an outstanding performance of the proposed technique from the visual and numerical *** segmentation process is performed using Otsu’smultiple thresholding *** method segments the image regions into five classes with variable intensities using four *** effectiveness is measured based on visual quality of the segmentation output,as it gives details about the image and positions of *** performance of the proposed framework is measured using Dice coefficient,Hausdorff,and Peak Signal-to-Noise Ratio(PSNR)*** segmented tumor region with the proposed segmentation method is 81%of the ground truth region provided by an ***,the proposed framew

关键词： Breast cancer mammogram images CAD contrast enhancement fuzzy logic segmentation

Pressure-induced phase transition in transition metal trifluorides

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Chinese Physics B 2022年第10期31卷 102-106页

作者：刘鹏徐美玲吕健高朋越黄呈熙李印威王建云王彦超周密 State Key Laboratory of Superhard Materials&international Center for Computational Method and Software College of PhysicsJilin UniversityChangchun 130012China Laboratory of Quantum Functional Materials Design and Application School of Physics and Electronic EngineeringJiangsu Normal UniversityXuzhou 221116China MIIT Key Laboratory of Semiconductor Microstructure and Quantum Sensing Nanjing University of Science and TechnologyNanjing 210094China

As a fundamental thermodynamic variable, pressure can alter the bonding patterns and drive phase transitions leading to the creation of new high-pressure phases with exotic properties that are inaccessible at ambient pressure. Using the swarm intelligence structural prediction method, the phase transition of TiF_(3), from R-3c to the Pnma phase, was predicted at high pressure, accompanied by the destruction of TiF_6 octahedra and formation of TiF_8 square antiprismatic units. The Pnma phase of TiF_(3), formed using the laser-heated diamond-anvil-cell technique was confirmed via high-pressure x-ray diffraction experiments. Furthermore, the in situ electrical measurements indicate that the newly found Pnma phase has a semiconducting character, which is also consistent with the electronic band structure calculations. Finally, it was shown that this pressure-induced phase transition is a general phenomenon in ScF_(3), VF_(3), CrF_(3), and MnF_(3), offering valuable insights into the high-pressure phases of transition metal trifluorides.

关键词： high-pressure structure transition crystal structure prediction high-pressure x-ray diffraction experiments transition metal

Dynamic Engaging Characteristics of Wet Clutch in Automatic Transmission

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Journal of Donghua University(English Edition) 2015年第3期32卷 357-362页

作者：刘艳芳郭伟张婧徐向阳 School of Transportation Science & Engineering Beihang University National PCAT Engineering Research Center international Education College Hefei University

Wet clutch is an important shifting component in automatic transmission,and its properties will affect the gear shift performance. By comparing the calculated and test results,the static friction torque model was proved to be capable of describing the real pressure and torque only in the situation of high-energy ***,a dynamic torque model was proposed on basis of hydrodynamic properties between friction surfaces, in which the clutch engagement was divided into three phases for hydrodynamic lubrication, mixed lubrication, and mechanical contact. The proposed dynamic torque model was validated by comparing the calculated and test results. The effects of temperature,pressure,and pressure changing rate of automatic transmission fluid( ATF) on the clutch torque were analyzed. Based on these results,the clutchto-clutch torque control during shifting in automatic transmission was optimized,and as a result,the shifting comfort was significantly improved since the problems such as the fluctuation and sudden drop of the engine rotating speed during shifting were eliminated.

关键词： automatic transmission wet clutch dynamic characteristics torque control friction

WeiTsing:A guard of the stele

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Molecular Plant 2023年第8期16卷 1237-1239页

作者： Muhammad Arslan Mahmood Rubab Zahra Naqvi Shahid Mansoor Plant Sciences Division Research School of BiologyThe Australian National UniversityCanberraACT2601Australia National Institute for Biotechnology and Genetic Engineering(NIBGE)College of Pakistan Institute of Engineering and Applied Science(PIEAS) FaisalabadPakistan international Center for Chemical and Biological Sciences(ICCBS) University ofKarachiKarachiPakistan

Soil-borne pathogens,e.g.,Plasmodiophora brassicae,causes devastating clubroot disease,and existing identified resistance(R)genes has been broken down with the co-evolution of pathogen,threatening the future of cruciferous ***,there is a dire need to identify new R genes for developing clubroot-resistant ***,Wang et al.,2023 have reported a new R gene,WeiTsing,that confers complete resistance to Plasmodiophora brassicae,providing an opportunity to deliver broad-spectrum,durable clubroot-resistant crop varieties.

关键词： al. guard resistance

Ovule initiation:the essential step controlling offspring number in Arabidopsis

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Journal of Integrative Plant Biology 2022年第8期64卷 1469-1486页

作者： Shi-Xia Yu Yu-Tong Jiang Wen-Hui Lin The Joint international Research Laboratory of Metabolic and Developmental Sciences School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China Shanghai Collaborative Innovation Center of Agri‐Seeds/Joint Center for Single Cell Biology Shanghai Jiao Tong UniversityShanghai 200240China School of Agriculture and Biology Shanghai Jiao Tong UniversityShanghai 200240China

Seed is the offspring of *** produce large numbers of seeds to ensure effective reproduction and survival in varying *** is a fundamentally important organ and is the precursor of the *** Arabidopsis and other plants characterized by multi-ovulate ovaries,ovule initiation determines the maximal ovule number,thus greatly affecting seed number per fruit and seed *** the regulatory mechanism of ovule initiation has both scientific and economic ***,the genetic and molecular basis underlying ovule initiation remains unclear due to technological *** recently,rules governing the multiple ovules initiation from one placenta have been identified,the individual functions and crosstalk of phytohormones in regulating ovule initiation have been further characterized,and new regulators of ovule boundary are reported,therefore expanding the understanding of this *** this review,we present an overview of current knowledge in ovule initiation and summarize the significance of ovule initiation in regulating the number of plant offspring,as well as raise insights for the future study in this field that provide potential routes for the improvement of crop yield.

关键词： asynchronous initiation of ovule primordia early and late ovule initiation placenta elongation plant hormones seed number per fruit