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2018-2021年北京市某区腹泻病例粪便中肺炎克雷伯菌的病原学和分子特征分析

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中国人兽共患病学报 2024年第8期40卷 745-749,757页

作者：张爽赵娟刘畅王海瑞杨茜王会波王园园李辉张建涛张振东陈楠李颖张茂俊田睿北京市顺义区疾病预防控制中心北京101300 海关总署(北京)国际旅行卫生保健中心北京100013 内蒙古科技大学包头医学院内蒙古014040 中国疾病预防控制中心传染病预防控制所北京102206

目的了解北京市某区腹泻病例粪便中肺炎克雷伯菌(Klebsiella pneumoniae,KP)的病原学和分子特征。方法收集2018-2021年北京市某区门诊腹泻病例的粪便样本,进行KP分离培养鉴定,对KP分离株进行耐药表型检测和全基因组测序,测序结果进行多... 详细信息

目的了解北京市某区腹泻病例粪便中肺炎克雷伯菌(Klebsiella pneumoniae,KP)的病原学和分子特征。方法收集2018-2021年北京市某区门诊腹泻病例的粪便样本,进行KP分离培养鉴定,对KP分离株进行耐药表型检测和全基因组测序,测序结果进行多位点序列分析(Multilocus sequence typing,MLST)并建立全基因组系统进化树,同时分析病例的流行病学和临床特征。结果2018-2021年共检测粪便样本1103份,KP总检出率10.43%(115/1103),与其他致泻病原的混合感染率为42.61%(49/115)。女性阳性检出率稍高,为12.47%(61/489),16~45岁的青壮年检出最多,在1月、4~5月和8~9月3个时间段分别出现阳性小高峰。病例消化道症状以恶心为主,多为水样便。115株KP菌株耐药率前3位为氨苄西林、四环素和磺胺异噁唑,共有29株菌株对3类以上抗生素耐药。菌株共分为72种序列型(Sequence type,ST),其中ST23型最多,系统进化树显示菌株可分为4个主要分支,其中有14株ST23型菌株与高毒力NTUH-K2044参考株亲缘关系非常接近。结论北京市某区腹泻病例粪便样本中持续存在KP感染,女性、青壮年易感。本地区KP耐药情况严峻,ST型多样,且存在与高毒力菌株亲缘关系非常接近的ST23型致病菌株。

关键词：肺炎克雷伯菌药敏全基因组测序

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Establishment and Modification of Ninety-seven Pneumococcal Serotyping Assays Based on Quantitative Real-time Polymerase Chain Reaction

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生物医学与环境科学:英文版 2023年第9期36卷 787-799页

作者： CHE Jie CHEN Bo Han XU Li GAO Yuan YUE Meng Meng CHEN Zi Man zhang mao jun SHAO Zhu jun National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases National Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China School of Public Health Nanjing Medical UniversityNanjing 210029Jiangsu China

Objective To establish and modify quantitative real-time polymerase chain reaction(qPCR)-based serotyping assays to distinguish 97 pneumococcal *** A database of capsular polysaccharide(cps)loci sequences was generated,covering 97 pneumococcal *** analyses were performed to identify the cps loci structure and target genes related to different pneumococcal serotypes with specific SNPs.A total of 27 novel qPCR serotyping assay primers and probes were established based on qPCR,while 27 recombinant plasmids containing serotype-specific DNA sequence fragments were constructed as reference target sequences to examine the specificity and sensitivity of the qPCR assay.A panel of pneumococcal reference strains was employed to evaluate the capability of pneumococcal *** A total of 97 pneumococcal serotyping assays based on qPCR were established and modified,which included 64 serotypes previously reported as well as an additional 33 ***-seven novel qPCR serotyping target sequences were implemented in the pneumococcal qPCR serotyping system.A total of 97 pneumococcal serotypes,which included 52 individual serotypes and 45 serotypes belonging to 20 serogroups,could not be identified as individual *** sensitivity of qPCR assays based on 27 target sequences was 1–100 copies/μ*** specificity of the qPCR assays was 100%,which were tested by a panel of 90 serotypes of the pneumococcal reference *** A total of 27 novel qPCR assays were established and modified to analyze 97pneumococcal serotypes.

关键词： Streptococcus pneumoniae Serotyping cps loci Quantitative real-time PCR(qPCR)

Genetic Characteristics of Lipooligosaccharide and Capsular Polysaccharide of Campylobacter jejuni from Different Sources in China

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Biomedical and Environmental Sciences 2022年第12期35卷 1106-1114页

作者： WANG Jia Qi CHEN Xiao Li ZHOU Gui Lan WANG Hai Rui GU Yi Xin zhang Jian Zhong SHAO Zhu jun zhang mao jun State Key Laboratory for Infectious Disease Prevention and Control National Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China National Institute of Environmental Health Chinese Center for Disease Control and PreventionBeijing 100021China

Objective To determine the distribution of two important virulence factors[lipooligosaccharide(LOS)and capsular polysaccharide(CPS)]in Campylobacter jejuni(***)isolated from different sources in China and to develop a rapid screening method for Guillain–Barrésyndrome(GBS)-associated *** Whole-genome sequencing was carried out for 494 *** *** Ortho MCL software was used to define the LOS/CPS gene *** genotyping was performed with serotype-specific sequence alignment using the BLAST ***-time Polymerase chain reaction(PCR)was developed with the unique sequences of specific CPS *** Nine novel and 29 previously confirmed LOS classes were *** classes A,B,and C were the most common(48.2%,238/494)among the 494 ***-six capsular types were identified in 448 ***2,HS4c,HS5/31,HS19,and HS8/17 were the most frequent CPS genotypes(58.7%,263/448).Strains of 17 CPS genotypes(strain number>5)had one or two prevalent LOS classes(P<0.05).Multiplex real-time PCR for rapid identification of HS2,HS19,and HS41 was developed and validated with strains of known *** Our results describe the genetic characteristics of the important virulence factors in *** strains in *** multiplex real-time PCR developed in this study will facilitate enhanced surveillance of GBS-associated strains in China.

关键词： Campylobacter jejuni Lipooligosaccharide Capsular polysaccharide Multiplex real-time PCR

Genetic and Phenotypic Variation of Campylobacter jejuni NCTC11168 Caused by flhA Mutation during Laboratory Passage

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Biomedical and Environmental Sciences 2023年第7期36卷 604-613页

作者： CHEN Xiao Li LIANG Hao GUO Peng Bo GU Yi Xin WANG Jia Qi WANG Hai Rui ZHOU Gui Lan SHAO Zhu jun zhang Jian Zhong zhang mao jun State Key Laboratory for Infectious Disease Prevention and Control National Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China Department of Microbiology School of Public HealthCheeloo College of MedicineShandong UniversityJinan 250100ShandongChina Shandong First Medical University Shandong Academy of Medical SciencesJinan 250000ShandongChina

Objective Campylobacter jejuni NCTC11168 is commonly used as a standard strain for flagellar biosynthesis *** this report,two distinguished phenotypic isolates(CJ1Z,flhA mutant strain,lawn;CJ2S,flhA complemented strain,normal colony)appeared during laboratory passages for *** Phenotypic assessments,including motility plates,transmission electron microscopy,biofilm formation assay,autoagglutination assay,and genome re-sequencing for these two isolates(CJ1Z,flhA mutant strain;CJ2S,flhA complemented strain)were carried out in this *** Transmission electron microscopy revealed that the flagellum was lost in *** assessments and genome sequencing of the two isolates were performed in this *** capacity for biofilm formation,colony auto-agglutination,and isolate motility was reduced in the mutant *** genomic analysis indicated a unique native nucleotide insertion in flhA(nt,2154)that caused the I719Y and I720Y mutations and early truncation in *** FlhA has been found to influence the expression of flagella in *** the best of our knowledge,this is the first study to describe the function of the C-terminal of this protein.

关键词： Campylobacter jejuni Phenotypic variation Comparative genomics flhA

Inclusions modification by rare earth in steel and the resulting properties: A review

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Journal of Rare Earths 2024年第3期42卷 431-445,I0001页

作者： Xiaoqiang Wang Zhiwei Wu Bing Li Wenxiong Chen jun zhang Jian mao College of Materials Science and Engineering Sichuan UniversityChengdu610065China Chengdu Advanced Metal Materials Industry Technology Research Institute Co. Ltd.Chengdu610303China State Key Laboratory of Metal Material for Marine Equipment and Application Anshan114009China

Rare earth(RE) elements are excellent modifiers for non-metallic inclusions that inevitably appear in steel and affect steel properties. This paper reviews the research status of inclusions modification by RE elements and the changes it cause on steel properties. First, the inclusion changes caused by RE modification are described. Generally, after adding pure RE, the main evolution of inclusions occurs as M →M + RE-Al-O → RE-Al-O + RE_(2)O_(2)S → RE_(2)O_(2)S + RE—S/RE_(2)O_(2)S + RE-O with an increase in the RE content(M represents the inclusions before RE addition). The type of final inclusion obtained after RE modification is related to the relative contents of S and O in the steel. Moreover, fine, regular, and uniformly distributed inclusions can be obtained with appropriate RE addition. However, the effectiveness of inclusions modification by adding both RE and non-RE elements is closely related to the order of their addition. Second, the applications and advantages of thermodynamic calculations in the study of RE-modified inclusions are introduced. Third, the changes in the corrosion resistance, impact properties,and other properties of steel caused by the modification of inclusions by RE are reviewed. Finally, the perspectives and trends of inclusions modified by RE elements in the steel industry are presented.

关键词： Rare earths Inclusions Modification Thermodynamic calculation Properties change

Evolution of copper species during heat treatment and its effect on CO oxidation reaction on CuCeZrO_(y) catalyst synthesized by a facile solvent-free route

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Journal of Rare Earths 2024年第4期42卷 660-667页

作者： Guangying Fu Dongsen mao jun Yu Qiangsheng Guo School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai21418 China The ZeoMat Group Qingdao Institute of Bioenergy and Bioprocess TechnologyCASQingdao26611China

Several ternary oxides CuCeZrO_(y)(CCZ)were synthesized by a facile grinding method followed by calcination at high temperatures,and used as catalysts for CO oxidation at low *** influences of calcination temperature(400-600℃)on the physicochemical properties of the assynthesized ternary oxides were investigated by thermogravimetric analysis/differential scanning calorimetry(TGA/DSC),X-ray diffraction(XRD),transmission electron microscopy(TEM),Raman,inductively coupled plasma-optical emission spectrometry(ICP-OES),N_(2) adsorption,H_(2)-temperature programmed reduction(H_(2)-TPR),and X-ray photoelectron spectroscopy(XPS)*** results show that the increase in calcination temperature from 400 to 500℃is conducive to the high dispersion of CuOx on catalyst surface and the incorporation of Cu species into the support to form the Cu-Ce-Zr-O solid *** raising of calcination temperature from 500 to 600℃,however,leads to the segregation of Cu species from the solid solution to aggregate on support surface and growth of highly dispersed CuOx *** highest catalytic activity is acquired over the CCZ calcined at 500℃,which can be ascribed to the largest contents of Cu+species and oxygen vacancies owing to the formation of the maximum amount of Cu-Ce-Zr-O solid solution.

关键词： CuCeZrO_(y)catalyst co oxidation Calcination temperature Grinding method Oxalate precursor Rare earths

Impacts of information about COVID-19 on pig farmers'production willingness and behavior:Evidence from China

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Journal of Integrative Agriculture 2024年第4期23卷 1429-1441页

作者： Huan Chen Lei mao Yuehua zhang School of Public Affairs Zhejiang UniversityHangzhou 310058China School of Insurance Central University of Finance and EconomicsBeijing 100081China Innovation Center of Yangtze River Delta Zhejiang UniversityJiaxing 314100China

This paper examines the impacts of information about COVID-19 on pig farmers'production willingness by using endorsement experiments and follow-up surveys conducted in 2020 and 2021 in *** results show that,first,farmers were less willing to scale up production when they received information about *** information in 2020 that the second wave of COVID-19 might occur without a vaccine reduced farmers'willingness to scale up by 13.4%,while the information in 2021 that COVID-19 might continue to spread despite the introduction of vaccine reduced farmers'willingness by 4.4%.Second,farmers whose production was affected by COVID-19 were considerably less willing to scale up,given the access to COVID-19 ***,farmers'production willingness can predict their actual production behavior.

关键词： COVID-19 randomized experiment information treatment production willingness

Geometric Error Identification of Gantry-Type CNC Machine Tool Based on Multi-Station Synchronization Laser Tracers

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 150-162页

作者： jun Zha Huijie zhang School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Xi’an Jiaotong University Suzhou Academy Suzhou 215123China

Laser tracers are a three-dimensional coordinate measurement system that are widely used in industrial *** propose a geometric error identification method based on multi-station synchronization laser tracers to enable the rapid and high-precision measurement of geometric errors for gantry-type computer numerical control(CNC)machine *** method also improves on the existing measurement efficiency issues in the single-base station measurement method and multi-base station time-sharing measurement *** consider a three-axis gantry-type CNC machine tool,and the geometric error mathematical model is derived and established based on the combination of screw theory and a topological analysis of the machine kinematic *** four-station laser tracers position and measurement points are realized based on the multi-point positioning principle.A self-calibration algorithm is proposed for the coordinate calibration process of a laser tracer using the Levenberg-Marquardt nonlinear least squares method,and the geometric error is solved using Taylor’s first-order linearization *** experimental results show that the geometric error calculated based on this modeling method is comparable to the results from the Etalon laser *** a volume of 800 mm×1000 mm×350 mm,the maximum differences of the linear,angular,and spatial position errors were 2.0μm,2.7μrad,and 12.0μm,respectively,which verifies the accuracy of the proposed *** research proposes a modeling method for the precise measurement of errors in machine tools,and the applied nature of this study also makes it relevant both to researchers and those in the industrial sector.

关键词： Multi-point positioning Multi-station synchronization CNC machine tool Geometric error Error separation

Nanomaterial‑Based Repurposing of Macrophage Metabolism and Its Applications

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Nano-Micro Letters 2024年第11期16卷 494-528页

作者： Tingting Meng Danfeng He Zhuolei Han Rong Shi Yuhan Wang Bibo Ren Cheng zhang Zhengwei mao Gaoxing Luo jun Den Institute of Burn Research Southwest HospitalState Key Laboratory of Trauma and Chemical PoisoningArmy Medical UniversityChongqing 400038People’s Republic of China Department of Breast Surgery Gansu Provincial HospitalLanzhouGansu 730030People’s Republic of China MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China

Macrophage immunotherapy represents an emerging therapeutic approach aimed at modulating the immune response to alleviate disease ***(NMs)have been engineered to monitor macrophage metabolism,enabling the evaluation of disease progression and the replication of intricate physiological signal *** achieve this either directly or by delivering regulatory signals,thereby mapping phenotype to effector functions through metabolic repurposing to customize macrophage fate for ***,a comprehensive summary regarding NM-mediated macrophage visualization and coordinated metabolic rewiring to maintain phenotypic equilibrium is currently *** review aims to address this gap by outlining recent advancements in NM-based metabolic *** initially explore the relationship between metabolism,polarization,and disease,before delving into recent NM innovations that visualize macrophage activity to elucidate disease onset and fine-tune its fate through metabolic remodeling for macrophage-centered ***,we discuss the prospects and challenges of NM-mediated metabolic immunotherapy,aiming to accelerate clinical *** anticipate that this review will serve as a valuable reference for researchers seeking to leverage novel metabolic intervention-matched immunomodulators in macrophages or other fields of immune engineering.

关键词： Immunomodulatory nanomaterial Macrophage polarization Macrophage metabolic reprogramming Immune engineering