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Molecular mechanism of mureidomycin biosynthesis activated by introduction of an exogenous regulatory gene ssa A into Streptomyces roseosporus

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Science China(Life Sciences) 2021年第11期64卷 1949-1963页

作者： Ning Liu Hanye Guan Guoqing Niu lingjuan jiang Yue Li Jihui Zhang Jine Li Huarong Tan State Key Laboratory of Microbial Resources Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China Biotechnology Research Center Southwest UniversityChongqing 400715China Department of Medical Research Center Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China

Mureidomycins(MRDs), a group of unique uridyl-peptide antibiotics, exhibit antibacterial activity against the highly refractory pathogen Pseudomonas aeruginosa. Our previous study showed that the cryptic MRD biosynthetic gene cluster(BGC) mrd in Streptomyces roseosporus NRRL 15998 could not be activated by its endogenous regulator 02995 but activated by an exogenous activator Ssa A from sansanmycin’s BGC ssa of Streptomyces sp. strain SS. Here we report the molecular mechanism for this inexplicable regulation. EMSAs and footprinting experiments revealed that Ssa A could directly bind to a 14-nt palindrome sequence of 5′-CTGRCNNNNGTCAG-3′ within six promoter regions of mrd. Disruption of three representative target genes(SSGG-02981, SSGG-02987 and SSGG-02994) showed that the target genes directly controlled by Ssa Awere essential for MRD production. The regulatory function was further investigated by replacing six regions of SSGG-02995 with those of ssa ***, only the replacement of 343–450 nt fragment encoding the 115–150 amino acids(AA) of Ssa A could activate MRD biosynthesis. Further bioinformatics analysis showed that the 115–150 AA situated between two conserved domains of Ssa *** findings significantly demonstrate that constitutive expression of a homologous exogenous regulatory gene is an effective strategy to awaken cryptic biosynthetic pathways in Streptomyces.

关键词： mureidomycin transcriptional activation exogenous regulator—SsaA cryptic gene cluster Streptomyces roseosporus Pseudomonas aeruginosa antibiotics

A high-fiber diet synergizes with Prevotella copri and exacerbates rheumatoid arthritis

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Cellular & Molecular Immunology 2022年第12期19卷 1414-1424页

作者： lingjuan jiang Mengmeng Shang Shengnan Yu Yudong Liu Hui Zhang Yangzhong Zhou Min Wang Tingting Wang Hui Li Zhihua Liu Xuan Zhang Department of Medical Research Center National Science and Technology Key Infrastructure on Translational MedicinePeking Union Medical College HospitalDepartment of RheumatologyBeijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100730China State Key Laboratory of Complex Severe and Rare Diseases Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100730China Department of Rheumatology Beijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineClinical Immunology CenterChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100730China Department of Pathology Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100730China Department of Internal Medicine Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100730China Key Laboratory of Infection and Immunity Institute of BiophysicsChinese Academy of SciencesBeijing100101China Institute for Immunology School of MedicineTsinghua UniversityBeijing100084China Tsinghua-Peking Center for Life Sciences Beijing100084China

Both preclinical and established rheumatoid arthritis(RA)patients display alterations in the gut *** *** preferentially enriched in a subset of RA ***,we isolated a Prevotella strain,*** RA,from the feces of RA patients and showed that colonization of *** RA exacerbated arthritis in a collagen-induced arthritis(CIA)*** the presence of *** RA colonization,a high-fiber diet exacerbated arthritis via microbial alterations and intestinal *** of *** together with a high-fiber diet enabled the digestion of complex fiber,which led to the overproduction of organic acids,including fumarate,succinate and short-chain fatty *** promoted proinflammatory responses in macrophages,and supplementation with succinate exacerbated arthritis in the CIA *** findings highlight the importance of dysbiosis when evaluating the effects of dietary interventions on RA pathogenesis and provide new insight into dietary interventions or microbiome modifications to improve RA management.

关键词： Rheumatoid arthritis Dysbiosis Prevotella copri High-fber diet Microbiota-derived metabolites

Helicobacter pylori may participate in the development of inflammatory bowel disease by modulating the intestinal microbiota

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Chinese Medical Journal 2022年第6期135卷 634-638页

作者： Xiaoyin Bai lingjuan jiang Gechong Ruan Tingting Liu Hong Yang Department of Gastroenterology Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Department of Medical Research Center Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China

Inflammatory bowel disease(IBD)is a non-specific inflammatory disease of the gastrointestinal(GI)tract that is generally accepted to be closely related to intestinal dysbiosis in the *** infections contribute a key role in the pathogenesis of IBD;however,although the results of recent clinical studies have revealed an inverse correlation between Helicobacter pylori(***)infection and IBD,the exact mechanism underlying the development of IBD remains ***,as a star microorganism,has been a focus for decades,and recent preclinical and real-world studies have demonstrated that *** not only affects the changes in the gastric microbiota and microenvironment but also influences the intestinal microbiota,indicating a potential correlation with *** analysis revealed that *** infection increased the diversity of the intestinal microbiota,reduced the abundance of Bacteroidetes,augmented the abundance of Firmicutes,and produced short-chain fatty acid-producing bacteria such as *** these factors may decrease vulnerability to *** studies investigating the ***-intestinal microbiota metabolite axis should be performed to understand the mechanism underlying the development of IBD.

关键词： H.pylori Helicobacter inflammatory

Proximity-enabled covalent binding of IL-2 to IL-2Rα selectively activates regulatory T cells and suppresses autoimmunity

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Signal Transduction and Targeted Therapy 2023年第2期8卷 795-812页

作者： Bo Zhang Jiaqi Sun Yeshuang Yuan Dezhong Ji Yeting Sun Yudong Liu Shengjie Li Xingxing Zhu Xunyao Wu Jin Hu Qiu Xie Ling Wu Lulu Liu Boyang Cheng Yuanjie Zhang lingjuan jiang Lidan Zhao Fei Yu Wei Song Min Wang Yue Xu Shiliang Ma Yunyun Fei Lihe Zhang Demin Zhou Xuan Zhang State Key Laboratory of Complex Severe and Rare Diseases Peking Union Medical College HospitalDepartment of RheumatologyBeijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China Department of Rheumatology Beijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineClinical Immunology CenterGraduate School of Peking Union Medical CollegeChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Department of Rheumatology and Clinical Immunology Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeThe Ministry of Education Key LaboratoryBeijing 100730China

Interleukin-2(IL-2)is a pleiotropic cytokine that orchestrates bidirectional immune responses via regulatory T cells(Tregs)and effector cells,leading to paradoxical ***,we report a strategy that exploited genetic code expansion-guided incorporation of the latent bioreactive artificial amino acid fluorosulfate-L-tyrosine(FSY)into IL-2 for proximity-enabled covalent binding to IL-2Rαto selectively promote Treg *** found that FSY-bearing IL-2 variants,such as L72-FSY,covalently bound to IL-2Rαvia sulfur-fluoride exchange when in proximity,resulting in persistent recycling of IL-2 and selectively promoting the expansion of Tregs but not effector *** assessment of L72-FSY-expanded Tregs demonstrated that L72-FSY maintained Tregs in a central memory phenotype without driving terminal differentiation,as demonstrated by simultaneously attenuated expression of lymphocyte activation gene-3(LAG-3)and enhanced expression of programmed cell death protein-1(PD-1).Subcutaneous administration of L72-FSY in murine models of pristane-induced lupus and graft-versus-host disease(GvHD)resulted in enhanced and sustained therapeutic efficacy compared with wild-type IL-2 *** efficacy of L72-FSY was further improved by N-terminal PEGylation,which increased its circulatory retention for preferential and sustained *** proximity-enabled covalent binding strategy may accelerate the development of pleiotropic cytokines as a new class of immunomodulatory therapies.

关键词： sustained proximity consequences

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我国学前融合教育研究综述

科教导刊 2016年第10期 37-38页

作者：蒋玲娟陇南师范高等专科学校甘肃陇南742500

近几年来,学前教育越来越受到国家的重视,无论是需要特殊对待的幼儿,还是正常的幼儿,都应该接受科学合理的学前教育。如今学前融合教育不断发展起来,成为学前教育的一种新模式。融合教育具有很多优势,它不仅可以促进正常幼儿的健康发展... 详细信息

近几年来,学前教育越来越受到国家的重视,无论是需要特殊对待的幼儿,还是正常的幼儿,都应该接受科学合理的学前教育。如今学前融合教育不断发展起来,成为学前教育的一种新模式。融合教育具有很多优势,它不仅可以促进正常幼儿的健康发展,还能够提高特殊幼儿的认知水平。本文对学前融合教育的相关研究、存在的问题进行了分析,并对学前融合教育未来的发展提出了相关建议。

关键词：学前融合教育特殊教育师资力量

Heat Transfer and Friction Characteristics of Printed Circuit Heat Exchangers with Different Channel Structures for S-CO_(2) Power System

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Journal of Thermal Science 2024年第3期33卷 1132-1147页

作者： jiang Tao LI Mingjia Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an710049China School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China

Printed circuit heat exchanger(PCHE)has been widely used in supercritical carbon dioxide(S-CO_(2))power systems because of its high heat transfer efficiency and good ***,due to the large variety of PCHE configurations,channel selection in practical applications lacks a ***,this paper discussed the heat transfer and friction characteristics and the synergy of three fields in the channel under the guidance of the field synergy principle for four typical PCHE ***,the comprehensive performance of four channels was ***,the heat transfer and friction factor correlations for S-CO_(2)in four channels were *** findings demonstrate that the synergy of velocity and pressure fields of the straight channel PCHE is better(β≈180°),so its resistance loss is relatively *** zigzag and sinusoidal wavy channels and the airfoil fins can reduce the angle a between the temperature gradient and velocity,thus enhancing the heat *** sinusoidal wavy channel can reduce flow resistance compared to the zigzag channel due to the rounded *** streamlined airfoil structure can guide the flow and reduce backflow,thus reducing resistance *** the range of Re studied in this paper,the maximum error of the proposed heat transfer and friction factor correlations of PCHE is 7.0%,which shows good fitting *** research in this paper can provide a reference for the selection and design of PCHE with different channel configurations.

关键词： printed circuit heat exchanger supercritical carbon dioxide typical channel structure field synergy analysis

An improved initial rotor position estimation method using high-frequency pulsating voltage injection for PMSM

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Defence Technology（防务技术） 2024年第3期33卷 19-29页

作者： Yang jiang Ming Cheng School of Electrical Engineering Southeast UniversityNanjing 210096China

High frequency pulsating voltage injection method is a good candidate for detecting the initial rotor position of permanent magnet synchronous ***,traditional methods require a large number of filters,which leads to the deterioration of system stability and dynamic *** order to solve these problems,a new signal demodulation method is proposed in this *** proposed new method can directly obtain the amplitude of high-frequency current,thus eliminating the use of filters,improving system stability and dynamic performance and saving the work of adjusting filter *** addition,a new magnetic polarity detection method is proposed,which is robust to current measurement ***,experiments verify the effectiveness of the method.

关键词： Initial position detection Signal demodulation algorithm Magnetic polarity detection Filter elimination

Co/CoO heterojunction rich in oxygen vacancies introduced by O2 plasma embedded in mesoporous walls of carbon nanoboxes covered with carbon nanotubes for rechargeable zinc-air battery

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Carbon Energy 2024年第7期6卷 14-25页

作者： Leijun Ye Weiheng Chen Zhong-Jie jiang Zhongqing jiang Key Laboratory of Optical Field Manipulation of Zhejiang Province Department of PhysicsZhejiang Sci-Tech UniversityHangzhouChina Department of Mechanical Engineering Ningbo University of TechnologyNingboChina Guangzhou Key Laboratory for Surface Chemistry of Energy Materials Guangdong Engineering and Technology Research Center for Surface Chemistry of Energy MaterialsCollege of Environment and EnergySouth China University of TechnologyGuangzhouChina

Herein,Co/CoO heterojunction nanoparticles(NPs)rich in oxygen vacancies embedded in mesoporous walls of nitrogen-doped hollow carbon nanoboxes coupled with nitrogen-doped carbon nanotubes(P-Co/CoOV@NHCNB@NCNT)are well designed through zeolite-imidazole framework(ZIF-67)carbonization,chemical vapor deposition,and O_(2) plasma *** a result,the threedimensional NHCNBs coupled with NCNTs and unique heterojunction with rich oxygen vacancies reduce the charge transport resistance and accelerate the catalytic reaction rate of the P-Co/CoOV@NHCNB@NCNT,and they display exceedingly good electrocatalytic performance for oxygen reduction reaction(ORR,halfwave potential[EORR,1/2=0.855 V *** hydrogen electrode])and oxygen evolution reaction(OER,overpotential(η_(OER,10)=377mV@10mA cm^(−2)),which exceeds that of the commercial Pt/C+RuO_(2) and most of the formerly reported ***,both the aqueous and flexible foldable all-solid-state rechargeable zinc-air batteries(ZABs)assembled with the P-Co/CoOV@NHCNB@NCNT catalyst reveal a large maximum power density and outstanding long-term cycling ***-principles density functional theory calculations show that the formation of heterojunctions and oxygen vacancies enhances conductivity,reduces reaction energy barriers,and accelerates reaction kinetics *** work opens up a new avenue for the facile construction of highly active,structurally stable,and cost-effective bifunctional catalysts for ZABs.

关键词： heterojunction oxygen evolution/reduction reaction oxygen vacancies rechargeable zinc–air battery three‐dimensional nitrogen‐doped hollow carbon nanoboxes

Hybrid rogue waves and breather solutions on the double-periodic background for the Kundu-DNLS equation

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Communications in Theoretical Physics 2024年第5期76卷 33-48页

作者： DongZhu jiang Zhaqilao College of Mathematics Science Inner Mongolia Normal UniversityHohhot 01022China Center for Applied Mathematical Science Inner MongoliaHohhot 010022China

In this paper,by using the Darboux transformation(DT)method and the Taylor expansion method,a new nth-order determinant of the hybrid rogue waves and breathers solution on the double-periodic background of the Kundu-DNLS equation is constructed when n is *** and rogue waves can be obtained from this determinant,*** to this,the hybrid rogue waves and breathers solutions on the different periodic backgrounds are given explicitly,including the single-periodic background,the double-periodic background and the plane wave background by selecting different *** addition,the form of the obtained solutions is summarized.

关键词： double-periodic background hybrid rogue waves and breather darboux transformation Kundu-DNLS equation