关键词： Carbapenem-resistant Klebsiella pneumoniae   ST20   NDM   chromosomal integrated IMP   plasmid recombination  

摘要： To investigate the epidemiology of ST20 carbapenem-resistant Klebsiella pneumoniae (CRKP) in China, and further explore the genomic characteristics of bla(IMP-4) and bla(NDM-1) coharboring isolates and plasmid contributions to resistance and fitness. Seven ST20 CRKP isolates were collected nationwide, and antimicrobial susceptibility testing was performed. Antimicrobial resistance genes, virulence genes, and plasmid replicons were identified via whole-genome sequencing, and clonality assessed via core-genome multilocus sequence typing. Furthermore, we found four dual-metallo-beta-lactamases (MBL)-harbouring isolates, the gene location was detected by Southern blotting, and plasmid location analysis showed that bla(IMP-4) was located on a separate plasmid, a self-conjugative fusion plasmid, or the bacterial chromosome. These isolates were subjected to long-read sequencing, the presence of bla(IMP-4) in different locations was identified by genomic comparison, and transposon units were detected via inverse PCR. We subsequently found that bla(IMP-4) on the fusion plasmid and bacterial chromosome was formed via intact plasmid recombination by the IS26 and ltrA, respectively, and the circular transposon unit was related to cointegration, however, bla(IMP-4) in different locations did not affect the gene stability. The bla(NDM-1)-harbouring plasmid contributed to the increased resistance to beta-lactams and shortened survival lag time which was revealed in plasmid cured isolates. In summary, the K. pneumoniae ST20 clone is a high-risk resistant clone. With the use of ceftazidime/avibactam, MBL-positive isolates, especially dual-MBL-harbouring isolates, should be given additional attention.

关键词： Hypervirulent Klebsiella pneumoniae   ceftazidime-avibactam resistance   CTX-M-71   OmpK36   non-carbapenemase-producing strain  

摘要： Objectives This study aimed at revealing the underlying mechanisms of the loss and gain of ceftazidime-avibactam susceptibility in a non-carbapenemase-producing hypervirulent Klebsiella pneumoniae (hvKp). Methods Here we longitudinally recovered 3 non-carbapenemase-producing K1-ST23 hvKp strains at a one-month interval (KP29105, KP29499 and KP30086) from an elderly male. Antimicrobial susceptibility testing, whole genome sequencing, transcriptomic sequencing, gene cloning, plasmid conjugation, quantitative real-time PCR (qRT-PCR), and SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) were conducted. Results Among the 3 hvKp strains, KP29105 was resistant to the third- and fourth-generation cephalosporins, KP29499 acquired resistance to both ceftazidime-avibactam and carbapenems, while KP30086 restored its susceptibility to ceftazidime-avibactam, imipenem and meropenem but retained low-level resistance to ertapenem. KP29105 and KP29499 carried plasmid-encoded genes bla(CTX-M-15) and bla(CTX-M-71), respectively, but KP30086 lost both. Cloning of gene bla(CTX-M-71) and conjugation experiment of bla(CTX-M-71)-carrying plasmid showed that the transformant and transconjugant were susceptible to ceftazidime-avibactam but had a more than 8-fold increase in MICs. Supplementation with an outer membrane permeabilizer could reduce the MIC of ceftazidime-avibactam by 32 folds, indicating that porins play a key role in ceftazidime-avibactam resistance. The OmpK35 of the 3 isolates was not expressed, and the OmpK36 of KP29499 and KP30086 had a novel amino acid substitution (L359R). SDS-PAGE and qRT-PCR showed that the expression of porin OmpK36 of KP29499 and KP30086 was significantly down-regulated compared with KP29105. Conclusions In summary, we reported the rare ceftazidime-avibactam resistance in a non-carbapenemase-producing hvKp strain. Resistance plasmid carrying blaCTX-M-71 and mutated OmpK36 had a synergetic effect on the resistance.

关键词： Attitudes   crime education   crime prevention   knowledge   lived experiences  

摘要： The purpose of this qualitative study is to explore the impact of crime prevention education on senior high school student's knowledge and attitudes toward crime. The study was conducted using a phenomenological approach, which involve in-depth interviews with a purposive sample of students. The participants were selected based on their involvement in crime prevention education programs and their experiences with crime-related issues. Data was collected using semi-structured interviews, which were audio-recorded and transcribed verbatim. The data was analyzed using a thematic analysis approach. This helped identify themes and patterns in the participants' responses. The study revealed that students who receive crime prevention education are more aware of crime-related issues and have a better understanding of how to prevent them. Moreover, crime prevention education programs portray limited systematic implementation, and in an age-appropriate manner, to ensure that students receive the right knowledge and skills to deal with crime-related issues. It is recommended that educational authorities may prioritize the development of a comprehensive curriculum model that covers a wide range of crime-related topics, including personal safety, community safety, cybercrime, substance abuse, and more to increase students' knowledge and awareness of crime prevention strategies and their understanding of the legal and ethical implications of criminal behaviours. Also, the school authority may establish partnerships with community organizations, law enforcement agencies, and relevant stakeholders to enhance the implementation of crime prevention programs. This collaboration can provide additional resources, expertise, and support to address challenges effectively.

关键词： Acute ST-segment elevated myocardial infarction   dual antiplatelet drugs   major adverse cardiovascular events   percutaneous coronary intervention   platelet index   tirofiban   vascular endothelial function  

摘要： This trial targeted to analyze the effects of different doses of tirofiban combined with dual antiplatelet drugs on platelet indices, vascular endothelial function, and major adverse cardiovascular events (MACE) in patients with acute ST-segment elevated myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI). A total of 180 patients with STEMI who underwent PCI were divided into Group A, Group B, and Group C (60 cases per group). Group A was given conventional medication, and Groups B and C were given a standard dose (10 mu g/kg) and a high dose (20 mu g/kg) of tirofiban on the basis of Group A, respectively. Thrombolysis in myocardial infarction (TIMI) myocardial perfusion grade and TIMI blood flow grade were compared. Myocardial enzymes, platelet indices, vascular endothelial function, inflammatory factors, and cardiac function indices were detected. In-hospital bleeding events and follow-up MACE were recorded. After PCI, Group C had a higher number of TIMI myocardial perfusion grade III and TIMI blood flow grade III versus Group A. Group C achieved the greatest changes in myocardial enzymes, platelet indices, vascular endothelial function-related factors, inflammatory factors, and cardiac function indices, followed by Group B and Group A. The incidence of bleeding events was higher in Group C than in Group A, and that of MACE in Group C was lower than in Group A. The addition of high-dose tirofiban to PCI and dual antiplatelet drugs for STEMI patients can improve myocardial blood perfusion, cardiac function, and vascular endothelial function, inhibit platelet activation and aggregation, and reduce the occurrence of MACE. What is the context?Acute myocardial infarction is a branch of acute coronary syndromes, which can be categorized into ST-segment elevation myocardial infarction and non-ST-segment elevation myocardial infarction. Percutaneous coronary intervention is a non-surgical, invasive treatment used to improve blood flow to isch

关键词： Higher education internationalization   central themes   external influences   scholarly discourse   literature review   Higher Education   International & Comparative Education   Multicultural Education  

摘要： The internationalization of higher education, driven by globalization, has developed structural diversity on a global scale. This study examines the theoretical and practical transformations in higher education internationalization since the millennium through a rigorous four-stage selection process guided by six inclusion criteria. Using Nvivo14 for thematic coding, 109 relevant articles from 1999 to 2024 were analyzed. On this basis, the key central themes of higher education internationalization, external influences, and the diverse participation of countries and regions in the discourse are revealed. Central concerns in the dialogue on higher education internationalization include its core nature, critical perspectives, operational practices and sustainability efforts. External factors intertwined with internationalization encompass governmental policies, ethnic and racial considerations, economic implications, cultural exchanges, and the broader context of globalization.

关键词： Botanic explorations   conservation   ethno-anthropology   geography   natural history  

摘要： Stephen Sommier and emile Levier were eminent botanists and plant collectors (but also ethno-anthropologists, geographers and photographers), best known for their scientific travels in Italy and abroad. This study accurately reconstructs the travel and collection itineraries of a trip through the Caucasus in 1890. The botanical importance of this journey is significant, with over 10,000 specimens collected, more than 1600 taxa identified, and over 250 newly described taxa based on the collected samples. The locations visited are placed in a time sequence on up-to-date georeferenced topographic maps. Furthermore, using dedicated heatmaps, we show the sites where the two explorers collected specimens that were later identified as taxa new to science. These maps will also be useful to botanists, historians, scholars and curators of natural history museums, who work with Caucasian flora and vegetation, ethno-anthropology, history of photography, and landscape.

关键词： Streptococcus suis   ST1   89K-lke PAIs   virulence   TNF-alpha  

摘要： Streptococcus suis is a significant and emerging zoonotic pathogen. ST1 and ST7 strains are the primary agents responsible for S. suis human infections in China, including the Guangxi Zhuang Autonomous Region (GX). To enhance our understanding of S. suis ST1 population characteristics, we conducted an investigation into the phylogenetic structure, genomic features, and virulence levels of 73 S. suis ST1 human strains from GX between 2005 and 2020. The ST1 GX strains were categorized into three lineages in phylogenetic analysis. Sub-lineage 3-1a exhibited a closer phylogenetic relationship with the ST7 epidemic strain SC84. The strains from lineage 3 predominantly harboured 89K-like pathogenicity islands (PAIs) which were categorized into four clades based on sequence alignment. The acquirement of 89K-like PAIs increased the antibiotic resistance and pathogenicity of corresponding transconjugants. We observed significant diversity in virulence levels among the 37 representative ST1 GX strains, that were classified as follows: epidemic (E)/highly virulent (HV) (32.4%, 12/37), virulent plus (V+) (29.7%, 11/37), virulent (V) (18.9%, 7/37), and lowly virulent (LV) (18.9%, 7/37) strains based on survival curves and mortality rates at different time points in C57BL/6 mice following infection. The E/HV strains were characterized by the overproduction of tumour necrosis factor (TNF)-alpha in serum and promptly established infection at the early phase of infection. Our research offers novel insights into the population structure, evolution, genomic features, and pathogenicity of ST1 strains. Our data also indicates the importance of establishing a scheme for characterizing and subtyping the virulence levels of S. suis strains.

关键词： Remote sensing   mineral exploration   research hotspots   bibliometric analysis   VOSviewer  

摘要： Mineral resources are an important material basis for the development of human society and have become a topic of global concern in the 21st century. This paper adopts the method of bibliometric analysis to summarise the research progress of global remote sensing in the field of mineral exploration from 2000 to 2022 and gives an outlook on the future research direction. In this study, we used bibliometric analysis to provide a comprehensive overview of the research progress of global remote sensing in the field of mineral exploration from 2000 to 2022, and to provide an outlook on future research directions. We analysed 37,977 publications related to this period covering 185 countries, 2646 journals 16,328 institutions 25,170 funding agencies, and 114,746 authors.

关键词： Staphylococcus aureus   ST398   RSaX28   virulence   RNAIII  

摘要： Staphylococcus aureus (S. aureus) is a notorious pathogen that cause metastatic or complicated infections. Hypervirulent ST398 clonotype strains, remarkably increased in recent years, dominated Community-associated S. aureus (CA-SA) infections in the past decade in China. Small RNAs like RNAIII have been demonstrated to play important roles in regulating the virulence of S. aureus, however, the regulatory roles played by many of these sRNAs in the ST398 clonotype strains are still unclear. Through transcriptome screening and combined with knockout phenotype analysis, we have identified a highly transcribed sRNA, RSaX28, in the ST398 clonotype strains. Sequence analysis revealed that RSaX28 is highly conserved in the most epidemic clonotypes of S. aureus, but its high transcription level is particularly prominent in the ST398 clonotype strains. Characterization of RSaX28 through RACE and Northern blot revealed its length to be 533nt. RSaX28 is capable of promoting the hemolytic ability, reducing biofilm formation capacity, and enhancing virulence of S. aureus in the in vivo murine infection model. Through IntaRNA prediction and EMSA validation, we found that RSaX28 can specifically interact with RNAIII, promoting its stability and positively regulating the translation of downstream alpha-toxin while inhibiting the translation of Sbi, thereby regulating the virulence and biofilm formation capacity of the ST398 clonotype strains. RSaX28 is an important virulence regulatory factor in the ST398 clonotype S. aureus and represents a potential important target for future treatment and immune intervention against S. aureus infections.

关键词： Aggregation   morphine   platelet   ST-segment elevation myocardial infarction   ticagrelor   troponin  

摘要： ST-segment elevation myocardial infarction (STEMI) is usually caused by a ruptured atherosclerotic plaque, with subsequent thrombus formation. Platelet inhibition and primary percutaneous coronary intervention (PCI) are essential treatments. Morphine, used to relieve pain and anxiety in STEMI patients, delays the onset of P2Y12 inhibitors. This study aimed to further explore the association between platelet activity and morphine treatment in patients with STEMI. In this sub-study of the VALIDATE-SWEDHEART trial, 89 STEMI patients treated with ticagrelor, and primary PCI were included. Platelet aggregation and biomarkers of platelet activity, coagulation, and inflammation (sP-selectin, thrombin-antithrombin complexes, prothrombin fragments 1 + 2, CD40L, CRP, beta-thromboglobulin, and pentraxin3) were assessed at three time points: before, one, and twelve hours after PCI. Of the 89 patients, 40 received morphine before hospital arrival. There were no significant differences in age, sex, medical history, or coronary disease extent. One hour after PCI, ADP-induced (36 vs 61, p < .001), arachidonic acid-induced (20 vs 36, p = .003), collagen-induced (48 vs 60, p = .03) aggregation, and the proportion of high on-treatment ADP-induced platelet reactivity (27% vs 60%, p = .001) were significantly higher in morphine-treated patients. No significant differences were found before or 12 hours after PCI. No significant differences in platelet activity biomarkers were observed. Morphine increased platelet aggregation in STEMI patients but did not affect biomarkers.