Objectives: To investigate the characteristics and clonal dynamics of tigecycline-resistant Acinetobacter baumannii (TRAB) isolates from a Chinese hospital from 2016 to 2021.
Methods: A total of 64 TRAB isolates were screened and WGS was performed. Phylogenetic analysis and non-polymorphic mutation analysis were used to analyse their clonal dynamics and tigecycline resistance-related mutations. RT-PCR was used to analyse the expression of the resistance-nodulation cell-division (RND) efflux pump genes adeB and adeJ. Gene cloning was used to explore the effect of tet(39) variants on tigecycline resistance.
Results: Most TRAB isolates were found to be MDR, with 95% (61/64) of the isolates showing resistance to carbapenems. These TRAB isolates were classified into three primary genetic clusters based on core-genome SNPs. The KL2 cluster persisted throughout the study period, whereas the KL7 cluster emerged in 2019 and became the dominant clone. The KL7 cluster carried more antimicrobial resistance genes than the other two clusters. The predominant tigecycline resistance mechanism of the KL2 cluster and KL7 cluster was IS insertion in adeN (82.1%, 23/28) and genetic alterations in adeS (76.2%, 16/21), respectively. Eleven novel AdeS mutations were identified associated with elevated AdeB expression and tigecycline resistance. Moreover, we characterized a plasmid-borne tet(39) variant with an Ala-36-Thr substitution that synergizes with the RND efflux pump to confer high-level tigecycline resistance.
Conclusions: This work provides important insights into the diverse mechanisms associated with tigecycline resistance in A. baumannii, highlighting a pressing need for further monitoring of ST2-KL7 A. baumannii in clinical settings.
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http://dx.doi.org/10.1093/jac/dkae314 | DOI Listing |
Endocrine
January 2025
Department of Endocrinology, Genetics and Metabolism, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China.
Purpose: This study aimed to determine the detection rate of autoimmune polyendocrine syndrome (APS) among children with Graves' disease (GD) at a single center and to compare clinical characteristics between those with isolated GD and those GD with APS (APS-GD).
Methods: A retrospective analysis was conducted on the clinical data of 555 patients and were categorized into isolated GD and APS-GD groups based on their progression status. The time for FT to return to normal was used as an indicator of short-term treatment effectiveness.
Rev Bras Med Trab
November 2024
Facultad de Medicina, Universidad Peruana Cayetano Heredia, Lima, Perú.
Introduction: The socioeconomic and health situation of people have been affected during the COVID-19 pandemic; in Peru, preventive labor measures were taken to promote home working, which generated working conditions requiring special attention.
Objectives: To describe the results of an online survey on working and health conditions in workers from Lima and Callao who worked from home during the first period of mandatory social isolation due to COVID-19.
Methods: In this exploratory study, an online survey adapted from the Questionnaire on Working Conditions, Employment and Health in Latin America and the Caribbean was applied between March 21 and April 11, 2020.
Prog Neurobiol
October 2024
Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, United States; Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX 77030, United States; Memorial Hermann Hospital, Texas Medical Center, Houston, TX 77030, United States. Electronic address:
How we combine minimal linguistic units into larger structures remains an unresolved topic in neuroscience. Language processing involves the abstract construction of 'vertical' and 'horizontal' information simultaneously (e.g.
View Article and Find Full Text PDFJ Antimicrob Chemother
November 2024
Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, Wenzhou, Zhejiang Province, China.
Eur J Microbiol Immunol (Bp)
September 2024
4Department of Basic Medical Science, Faculty of Medicine Vajira Hospital, Navamindradhiraj University, Dusit, Bangkok 10300, Thailand.
Tigecycline-resistant Acinetobacter baumannii (TRAB) is increasing in Thailand, complicating antibiotic treatment due to limited antibiotic options. The specific resistance mechanism behind tigecycline resistance is still unclear, necessitating further investigation. We investigated the presence of OXA-type carbapenemases, the antimicrobial susceptibility profile, the inhibitory effect of carbonyl cyanide m-chlorophenylhydrazone (CCCP) on tigecycline susceptibility, the expression levels of RND-type efflux pumps and amino acid substitutions within a two-component regulatory system on 30 Thai clinical isolates.
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