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In this article, the relationship between the mechanical properties of wood–plastic composite (WPC) parts fabricated by selective laser sintering (SLS) and the laser intensity is determined. Green parts were formed from WPC by SLS process, the SLS green parts had sufficient strengths for features to be built with relatively high dimensional accuracy. In order to improve the mechanical properties of the parts to better level, the post-processing – infiltration with wax – is used. Experiments for studying mechanical properties of WPC parts with laser intensity growing are carried on, the result is as following: because interfacial adhesion of copolyester and densification are improved with laser intensity growing, impact strength increased gradually either in green part style or in wax-infiltrated part style, tensile strength and bending strength of wax-infiltrated parts increased gradually. The tensile strength improved 191% and the bending strength improved 17%, with the increase in laser intensity from 226 Watt/mm2 to 311 Watt/mm2; the impact strength of green parts improved 543% and the impact strength of wax-infiltrated parts improved 147%, respectively, by increasing the laser intensity from 226 Watt/mm2 to 340 Watt/mm2. But when the laser intensity is greater than 311 Watt/mm2, the tensile strength and bending strength decreased for further increasing of the laser intensity, leading to higher temperature, making the melt viscosity of the copolyester drop. [ABSTRACT FROM AUTHOR]

Carbapenem-resistant Enterobacteriaceae have become widely prevalent globally because of antibiotic misuse and the spread of drug-resistant plasmids, where carbapenem-resistant Escherichia coli (CREC) is one of the most common and prevalent pathogens. Furthermore, E. coli has been identified as a member of normal gut flora and does not cause disease under normal circumstances. However, certain strains of E. coli , due to the expression of virulence genes, can cause severe intestinal and extra-intestinal infections. Therefore, clinically, drug resistance and pathogenic E. coli strains are significantly challenging to treat. In this study, a novel CREC strain DC8855 was isolated from the ascites of a patient with intestinal perforation, identified as a novel sequence type 12531 (ST12531) and an unreported serotype O8:H7. It was revealed that the resistance of ST12531 CREC was predominantly conferred by an IncFII(K) plasmid carrying bla NDM-4 . Furthermore, phylogenetic analysis indicated that this is the first discovery of such plasmids in China and the first identification in E. coli . Moreover, regarding virulence, the swimming assays, qRT-PCR, and in vitro intestinal barrier model indicated that DC8855 had significantly higher motility, flagella gene expression, and intestinal epithelial cell barrier migration ability than the other sequence types CREC strains (ST167 and ST410). In conclusion, this study identified novel CREC which was multidrug resistant as well as enteropathogenic and therefore requires continuous monitoring.

Objectives: Emergence of multidrug-resistant (MDR) Salmonella enterica serovar Indiana has raised global concern. Mobile genetic elements (MGEs) play vital roles in accelerating the dissemination of resistance genes in bacteria communities. The study aims to improve our understanding of the underlying resistance mechanisms and characterize the MGEs in a MDR S. Indiana isolate., Methods: Here, we report the characteristics of a MDR pathogenic S. Indiana isolate. The antimicrobial susceptibility pattern of S. Indiana QT6365 was determined. The genomic structure of the chromosome and the plasmid, serotype, and multi-locus sequence type were analysed by whole genome sequencing. The circular form derived from IS26-flanked transposon was confirmed by reverse polymerase chain reaction and sequencing., Results: S. Indiana QT6365 exhibited resistance to all tested antimicrobials except for aztreonam, amikacin, polymyxin, and tigecycline, was defined as MDR, and belonged to ST17. S. Indiana QT6365 was closely related with food resource S. Indiana C629 with similar resistance gene profiles. Multiple resistance genes are mainly carried by a novel transposon Tn7540 located on the chromosome and an IncHI2/HI2A/N plasmid. Sequence analysis and the formed circular intermediate suggested Tn7540 might be generated through homologous recombination by IS26-bounded translocatable units (IS26-fosA-IS26-intI1-dfrA12-aadA2-sul1-ISCR1-bla NDM-9 -IS26)., Conclusions: To the best of our knowledge, this is the first report of the novel chromosomal transposon possessing bla NDM-9 and fosA3 in S. Indiana isolated from human specimen, which might facilitate the dissemination of resistance genes and should arouse serious awareness., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Objective: Alar retraction is considered a challenge in rhinoplasty. The classification of alar retraction remains poorly defined, especially in Asia. Patients with alar retraction are associated with excessive exposure to the nostrils in Asia. This study aimed to introduce a classification method of alar retraction based on nostril exposure., Materials and Methods: Medical records of patients who had undergone rhinoplasty with alar retraction based on nostril exposure between January 2015 and December 2020 were retrospectively reviewed. The corrections of alar retraction were categorized into three groups according to a classification method of alar retraction based on nostril exposure: mild alar retraction, moderate alar retraction, and severe alar retraction. The visual analog scale (VAS) and rhinoplasty outcomes evaluation (ROE) were used to evaluate the satisfaction rate., Results: Within a median period of 13.3 months, 45 patients (51.14%) with mild alar retraction were corrected by alar contour graft. 23 patients (26.14%) with moderate alar retraction were treated with the alar contour graft(n=10), the lateral crural strut graft (n = 6), and the alar projection graft (n = 7). 20 patients (22.73%) with severe alar retraction were corrected by lateral crural strut graft combined with composite graft (n = 6), lateral crural strut graft (n = 10), and composite graft (n = 4). The severe alar retraction group had a higher satisfaction rate in ROE(P<0.05) and VAS (P<0.05) than moderate alar retraction and mild alar retraction at a follow-up of 12 months after surgery., Conclusions: The classification of alar retraction based on nostril exposure is more practical for rhinoplasty in Asia., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interest, (Copyright © 2022 Elsevier Masson SAS. All rights reserved.)

Background: N6-methyladenosine (m 6 A) RNA modification is vital for cancers because methylation can alter gene expression and even affect some functional modification. Our study aimed to analyze m 6 A RNA methylation regulators and m 6 A-related genes to understand the prognosis of early lung adenocarcinoma., Methods: The relevant datasets were utilized to analyze 21 m 6 A RNA methylation regulators and 5,486 m 6 A-related genes in m 6 Avar. Univariate Cox regression analysis, random survival forest analysis, Kaplan-Meier analysis, Chi-square analysis, and multivariate cox analysis were carried out on the datasets, and a risk prognostic model based on three feature genes was constructed., Results: Respectively, we treated GSE31210 ( n = 226) as the training set, GSE50081 ( n = 128) and TCGA data ( n = 400) as the test set. By performing univariable cox regression analysis and random survival forest algorithm in the training group, 218 genes were significant and three prognosis-related genes ( ZCRB1 , ADH1C , and YTHDC2 ) were screened out, which could divide LUAD patients into low and high-risk group ( P < 0.0001). The predictive efficacy of the model was confirmed in the test group GSE50081 ( P = 0.0018) and the TCGA datasets ( P = 0.014). Multivariable cox manifested that the three-gene signature was an independent risk factor in LUAD. Furthermore, genes in the signature were also externally validated using the online database. Moreover, YTHDC2 was the important gene in the risk score model and played a vital role in readers of m 6 A methylation., Conclusion: The findings of this study suggested that associated with m 6 A RNA methylation regulators and m 6 A-related genes, the three-gene signature was a reliable prognostic indicator for LUAD patients, indicating a clinical application prospect to serve as a potential therapeutic target., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Guo, Zhang, Wang, Wu, Zhang, Zhang, Xu, Shen, Zhang, Gu, Zeng, Jia and Yin.)

Background: Bloodstream infection (BSI) caused by multidrug-resistant Acinetobacter baumannii (MDR-AB) has been increasingly observed among hospitalized patients. The following study analyzed the epidemiology and microbiological characteristics of MDR-AB, as well as the clinical features, antimicrobial treatments, and outcomes in patients over a six years period in China., Methods: This retrospective study was conducted in a large tertiary hospital in China between January 2013 and December 2018. The clinical and microbiological data of all consecutive hospitalized patients with MDR-AB induced bloodstream infection were included and analyzed., Results: A total of 108 BSI episodes were analyzed. All MDR isolates belonged to ST2, a sequence type that has spread all over the world. Overall, ST2 strains showed strong biofilm formation ability, high serum resistance, and high pathogenicity. As for the clinical characteristics of the patient, 30-day mortality was 69.4% (75/108). The three main risk factors included mechanical ventilation, intensive care unit (ICU) stay, and thrombocytopenia; three protective factors included a change of antimicrobial regimen within 48 h after positive blood culture, use of the antibacterial agent combination, and more inpatient days. The most effective antibacterial regimen was the combination of cefoperazone/sulbactam and tigecycline., Conclusions: BSI caused by ST2 A.baumannii represents a difficult challenge for physicians, considering the high mortality associated with this infection. The combination of cefoperazone/sulbactam and tigecycline may be an effective treatment option.

Background: The widespread application of triclosan contributes to its residual deposition in urine, which provides an environment of long-term exposure to triclosan for the intestinal Escherichia coli. We determined the triclosan and antibiotic resistance characteristics of E. coli strains isolated from urine samples and further investigated the resistance mechanism and molecular epidemic characteristics of triclosan-resistant E. coli isolates., Methods: A total of 200 non-repetitive E. coli strains were isolated from urine samples and then identified. The minimum inhibitory concentrations (MICs) of triclosan and antibiotics, fabI mutation, efflux pump activity, the expression of 14 efflux pump encoding genes, and epidemiological characteristics were determined by the agar dilution method, polymerase chain reaction (PCR), carbonyl cyanide 3-chlorophenylhydrazone (CCCP) inhibition test, quantitative real-time polymerase chain reaction (RT-qPCR), multilocus sequence typing (MLST), and pulse-field gel electrophoresis (PFGE) for all triclosan-resistant isolates. Furthermore, we also investigated the effect of triclosan exposure in vitro on antibiotic susceptibility and the efflux pump encoding gene expressions of triclosan-susceptible strains via serial passage experiments., Results: Of the 200 E. coli isolates, 2.5% (n = 5) were found to be resistant to triclosan, and multidrug resistance (MDR) and cross-resistance phenotypes were noted for these triclosan-resistant strains. The triclosan-sensitive strains also exhibited MDR phenotypes, probably because of the high resistance rate to AMP, CIP, LVX, and GEN. Gly79Ala and Ala69Thr amino acid changes were observed in the triclosan-resistant strains, but these changes may not mediate resistance of E. coli to triclosan, because mutations of these two amino acids has also been detected in triclosan-susceptible strains. Moreover, except for DC8603, all other strains enhanced the efflux pumps activity. As compared with ATCC 25922, except for fabI, increased expressions were noted for all efflux pump encoding genes such as ydcV, ydcU, ydcS, ydcT, cysP, yihV, acrB, acrD, and mdfA among the studied strains with varying PFGE patterns and STs types. Unexpectedly, 5 susceptible E. coli isolates showed rapidly increasing triclosan resistance after exposure to triclosan in vitro for only 12 days, while MDR or cross-resistance phenotypes and the overexpression of efflux pump genes were recorded among these triclosan-induced resistant isolates., Conclusions: This is the first study to report that short-term triclosan exposure in vitro increases triclosan resistance in susceptible E. coli isolates. After acquiring resistance, these strains may present MDR or cross-resistance phenotypes. Moreover, triclosan resistance mainly involves the overexpression of fabI and efflux pumps in E. coli isolates.

Background: Heteroresistance is a phenomenon that occurs in all bacteria and can cause treatment failure. Yet, the exact mechanisms responsible for heteroresistance still remain unknown. The following study investigated the mechanisms of imipenem-heteroresistance and -resistance in Pseudomonas aeruginosa clinical isolates from Wenzhou, China., Methods: Imipenem resistance was detected by the agar dilution method; heteroresistance was determined by population analysis profiles. Biofilm formation assay and modified carbapenem inactivation methods were also performed. Polymerase chain reaction (PCR) was conducted to detect oprD , and quantitative real-time PCR was used to determine expression levels of oprD, ampC and four efflux pump coding genes ( mexB, mexD, mexE and mexY )., Results: Six imipenem-heteroresistant and -resistant P. aeruginosa isolates were selected respectively. Deficient oprD was detected in all resistant isolates and two heteroresistant isolates. No strains produced carbapenemases. Expression levels of oprD were down-regulated in heteroresistant isolates. Transcription levels of the mexE and mexY were significantly increased in all heterogeneous subpopulations compared with their respective native ones. Compared with the susceptible group, increased mean relative expression levels of mexE and mexY or the decreased mean relative expression levels of oprD were observed in the resistant group ( P < 0.05), whereas transcription levels of the mexB and mexD remained unchanged., Conclusion: Down-regulation of oprD contributed to the resistance and heteroresistance of imipenem in our P. aeruginosa clinical isolates. In addition, the marginal up-regulation of efflux systems may indirectly affect imipenem resistance. Contrarily, defective oprD was less common in our experimental heteroresistant strains than resistant strains., Competing Interests: The authors report no conflicts of interest in this work., (© 2020 Xu et al.)

Frequent vehicle-pedestrian conflicts deserve special attention for safety assessment at intersections. This study helps verify how the simulation as an innovative approach can be utilized for right-turning vehicle-pedestrian conflict assessment at intersection crosswalks prior to implementation. Various behavior models such as vehicle turning path, turning speed, gap acceptance model and pedestrian behavior model, have been established. Through integrating the calibrated models into one simulation platform, the stochastic behavior of vehicles and pedestrians under different geometric layouts and operational conditions can be reproduced. Based on the field data collected by an unmanned aerial vehicle (UAV) at two urban intersections in Beijing, China, it was demonstrated through validation of surrogate safety measures (SSMs), i.e., Post Encroachment Time (PET) and vehicle passing speed at conflict points, that the simulation model can reasonably represent the frequency and severity of conflict occurrence at signalized crosswalks. The sensitivity analysis results indicated that large dimensions and turning angles of intersections tend to result in undesirable safety performance., (Copyright © 2019 Elsevier Ltd. All rights reserved.)