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1.
ACS Appl Mater Interfaces ; 16(27): 35293-35302, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38940838

ABSTRACT

Ferroelectric materials have aroused increasing interest in the field of self-powered ultraviolet (UV) photodetectors (PDs) for their switchable spontaneous polarization. However, the utilization of ferroelectric materials to modulate the built-in electric field and energy band at the junction interface has rarely been investigated. Herein, we design and fabricate self-powered solar-blind UV PDs based on a Ga2O3/ZnO:V heterojunction. The performance of the Ga2O3/ZnO:V PD is significantly enhanced through the reasonable coupling of ferroelectricity and piezoelectricity within the ZnO:V film. The device at 260 nm exhibits excellent photoelectric properties with high peak responsivity of 64.5 mA/W, a specific detectivity of 3.8 × 1010 Jones, and a rise/decay time of 1.9/45.2 µs, together with reproducibility and stability. Systematical energy band diagram analysis reveals that the excellent performance of Ga2O3/ZnO:V PD can be attributed to the driving forces arising from the addition of the depolarization field and piezoelectric field, which increases the intensity of built-in electric field and promotes the separation and transport of photogenerated carriers at the heterojunction interface. The findings of our research provide a novel avenue and valuable guidance for the design of high-performance self-powered photodetectors.

2.
ACS Nano ; 18(4): 2906-2916, 2024 Jan 30.
Article in English | MEDLINE | ID: mdl-38252027

ABSTRACT

Hydrogels are emerging as stretchable electromagnetic interference (EMI) shielding materials because of their tissue-like mechanical properties and water-rich porous cellular structures. However, achieving high-performance hydrogel shields remains a challenge because enhancing conductivity often results in a compromise in deformation adoptability. This work proposes a treatment strategy involving sulfuric acid/titanium carbide MXene, which can simultaneously enhance the conductivity and stretchability of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/poly(vinyl alcohol) (PVA) double-network hydrogels. Multiple spectroscopic characterizations reveal that sulfuric acid promotes the linear conformation transition of the PEDOT molecular chain, while MXene increases charge delocalization and hydrogen bond cross-linking sites. The hydrogels, synthesized with a combined content of 0.6 wt % of MXene and PEDOT:PSS, exhibit an average X-band EMI SE of 41 dB. This performance is sustained at 94.5%, even following stretching and release at a strain of 200%. Interestingly, the EMI SE is found to linearly increase, reaching a value of 99 dB as the frequency is increased to 26.5 GHz. This increase is attributed to the enhanced water molecular polarization process, as supported by theoretical calculations of the impedance and attenuation constant. This work introduces a post-treatment technique that optimizes double-network hydrogels, providing deep insights into their EMI shielding mechanism and enabling high-performance EMI shielding with an ultralow conductive filler content.

3.
Sci Bull (Beijing) ; 68(23): 3027-3047, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-37949739

ABSTRACT

The spread of hypervirulent carbapenem-resistant Klebsiella pneumoniae (Hv-CRKP) is a global health concern. Here, we report the intrahospital colonization and spread of Hv-CRKP isolates in a tertiary hospital from 2017 to 2022. Analyses of 90 nonredundant CRKP isolates from 72 patients indicated that Hv-CRKP transferability relies on the dominant ST11-K64 clone. Whole-genome sequencing of 11 representative isolates gave 31 complete plasmid sequences, including 12 KPC-2 resistance carriers and 10 RmpA virulence vehicles. Apart from the binary vehicles, we detected two types of fusion plasmids, favoring the cotransfer of RmpA virulence and KPC-2 resistance. The detection of ancestry/relic plasmids enabled us to establish genetic mechanisms by which rare fusion plasmids form. Unexpectedly, we found a total of five rmpA promoter variants (P9T-P13T) exhibiting distinct activities and varying markedly in their geographic distributions. CRISPR/Cas9 manipulation confirmed that an active PT11-rmpA regulator is a biomarker for the "high-risk" ST11-K64/CRKP clone. These findings suggest clonal spread and clinical evolution of the prevalent ST11-K64/Hv-CRKP clones. Apart from improved public awareness of Hv-CRKP convergence, our findings might benefit the development of surveillance (and/or intervention) strategies for the dominant ST11-K64 lineage of the Hv-CRKP population in healthcare sectors.


Subject(s)
Carbapenem-Resistant Enterobacteriaceae , Klebsiella Infections , Humans , Klebsiella pneumoniae/genetics , Multilocus Sequence Typing , Klebsiella Infections/drug therapy , Plasmids/genetics , Carbapenem-Resistant Enterobacteriaceae/genetics , Carbapenems/pharmacology
4.
ACS Appl Mater Interfaces ; 15(32): 38612-38622, 2023 Aug 16.
Article in English | MEDLINE | ID: mdl-37531140

ABSTRACT

We have achieved significantly improved device performance in solar-blind deep-ultraviolet photodetectors fabricated from ß-Ga2O3 thin films grown via metal-organic chemical vapor deposition (MOCVD) on p-Si(111) substrates by improving material quality through the use of an AlN buffer layer. High-structural-quality ß-Ga2O3 films with a (-201) preferred orientation are obtained after the introduction of the AlN buffer. Under 3 V bias, the dark current reaches a minimum of 45 fA, and the photo-to-dark current ratio (PDCR) reaches 8.5 × 105 in the photodetector with the metal-semiconductor-metal (MSM) structure. The peak responsivity and detectivity are 38.8 A/W and 2.27 × 1015 cm·Hz1/2/W, respectively, which are 16.5 and 230 times that without the buffer layer. Additionally, benefiting from the introduction of the AlN layer, the photodetection performance of the ß-Ga2O3/AlN/Si heterojunction is significantly improved. The PDCR, peak responsivity, and detectivity for the ß-Ga2O3/AlN/p-Si photodetector at 5 V bias are 2.7 × 103, 11.84 A/W, and 8.31 × 1013 cm·Hz1/2/W, respectively. The improved structural quality of ß-Ga2O3 is mainly attributed to the decreased in-plane lattice mismatch of 2.3% for ß-Ga2O3(-201)/AlN(002) compared to that of 20.83% for ß-Ga2O3(-201)/Si(111), as well as the elimination of the native amorphous SiOx surface layer on the Si substrate during the initial growth of oxide thin films.

5.
Pathogens ; 12(7)2023 Jul 03.
Article in English | MEDLINE | ID: mdl-37513750

ABSTRACT

tet(X4) is the critical resistance gene for tigecycline degradation that has been continually reported in recent years. In particular, pathogenic bacteria carrying tet(X4) are a severe threat to human health. However, information describing Escherichia coli coharboring tet(X4) with virulence genes is limited. Here, we isolated an E. coli strain coharboring tet(X4) and the heat-stable toxin gene astA from a dead piglet. The strain named 812A1-131 belongs to ST10. The genome was sequenced using the Nanopore and Illumina platforms. The virulence genes astA and tet(X4) are located on the chromosome and in the IncHI1-type plasmid p812A1-tetX4-193K, respectively. The plasmid could be conjugatively transferred to recipient E. coli J53 with high frequency. In vivo experiments showed that strain 812A1-131 is pathogenic to Galleria mellonella and could colonize the intestines of mice. In summary, pathogenic E. coli could receive a plasmid harboring the tet(X4) gene, which can increase the difficulty of treatment. The prevalence and transmission mechanisms of pathogenic bacteria coharboring the tet(X4) gene need more attention.

6.
J Cardiothorac Surg ; 18(1): 241, 2023 Jul 31.
Article in English | MEDLINE | ID: mdl-37525284

ABSTRACT

BACKGROUND: Lung cancer (LC) is one of the most frequent cancers worldwide, as well as the leading cause of cancer-related death. Non-small cell lung cancer (NSCLC, which accounts for 85% of occurrences) is the main type of LC. MiRNAs appear to play a role in the occurrence and progression of many malignancies, according to mounting data. The underlying mechanism of miRNAs in regulating NSCLC cell biological activity and progression, on the other hand, is still being investigated. METHODS: QRT-PCR were used to detect miR-185-5p expression and YWHAZ mRNA in NSCLC. The CCK-8 assay was used to determine the tumor cells' ability to proliferate. Transwall assay was used to test the migratory and invasive properties of cells. Cell apoptosis was detected using flow cytometry. Tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein zeta (YWHAZ), E-Cadherin, N-Cadherin and cleaved-caspase3 protein expression were assessed using Western Blot. The bioinformatics analysis software StarBase2.0 predicted miR-185-5p downstream targets. To confirm the target association between miR-185-5p and YWHAZ, a luciferase experiment was used. In addition, an NCl-H1299 xenograft model was created to assess the anti-tumor impact of miR-185-5p in vivo. The expression level of YWHAZ in tumor tissues of small xenograft tumor model was detected by immunohistochemistry assay. RESULTS: Decreased miR-185-5p expression levels were observed in NSCLC. In vitro, over-expressed miR-185-5p decreased cell viability, proliferation, invasion/migration, and induced cell apoptosis, while inhibiting tumor growth in vivo. Dual-luciferase gene experiments confirmed that YWHAZ binds to miR-185-5p. Overexpression of YWHAZ partially restored the inhibitory effects of miR-185-5p on cell behaviors. CONCLUSION: MiR-185-5p was down-regulated in NSCLC, and that overexpressed miR-185-5p inhibited malignant behaviors of cells and tumor growth by negatively regulating YWHAZ.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , MicroRNAs , Humans , Carcinoma, Non-Small-Cell Lung/pathology , Lung Neoplasms/pathology , Tryptophan , Tyrosine 3-Monooxygenase , Cell Line, Tumor , Cell Proliferation/genetics , MicroRNAs/genetics , MicroRNAs/metabolism , Luciferases
7.
Front Microbiol ; 14: 1128905, 2023.
Article in English | MEDLINE | ID: mdl-37065147

ABSTRACT

The tigecycline resistance gene tet(X4) was widespread in various bacteria. However, limited information about the plasmid harboring the tet(X4) gene spread among the different species is available. Here, we investigated the transmission mechanisms of the tet(X4) gene spread among bacteria in a pig farm. The tet(X4) positive Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae and Enterobacter hormaeche were identified in the same farm. The whole genome sequencing (WGS) analysis showed that the K. pneumoniae belonged to ST727 (n = 11) and ST3830 (n = 1), E. cloacae and E. hormaeche belonged to ST524 (n = 1) and ST1862 (n = 1). All tet(X4) genes were located on the IncHI1 plasmids that could be conjugatively transferred into the recipient E. coli C600 at 30°C. Moreover, a fusion plasmid was identified that the IncHI1 plasmid recombined with the IncN plasmid mediated by ISCR2 during the conjugation from strains B12L to C600 (pB12L-EC-1). The fusion plasmid also has been discovered in a K. pneumoniae (K1L) that could provide more opportunities to spread antimicrobial resistance genes. The tet(X4) plasmids in these bacteria are derived from the same plasmid with a similar structure. Moreover, all the IncHI1 plasmids harboring the tet(X4) gene in GenBank belonged to the pST17, the newly defined pMLST. The antimicrobial susceptibility testing was performed by broth microdilution method showing the transconjugants acquired the most antimicrobial resistance from the donor strains. Taken together, this report provides evidence that IncHI1/pST17 is an important carrier for the tet(X4) spread in Enterobacteriaceae species, and these transmission mechanisms may perform in the environment.

8.
Health Inf Sci Syst ; 11(1): 20, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37035724

ABSTRACT

The growth of databases in the healthcare domain opens multiple doors for machine learning and artificial intelligence technology. Many medical devices are available in the medical field; however, medical errors remain a severe challenge. Different algorithms are developed to identify and solve medical errors, such as detecting anomalous readings, anomalous health conditions of a patient, etc. However, they fail to answer why those entries are considered an anomaly. This research gap leads to an outlying aspect mining problem. The problem of outlying aspect mining aims to discover the set of features (a.k.a subspace) in which the given data point is dramatically different than others. In this paper, we present a framework that detects anomalies in healthcare data and then provides an explanation of anomalies. This paper aims to effectively and efficiently detect anomalies and explain why they are considered anomalies by detecting outlying aspects. First, we re-introduced four anomaly detection techniques and outlying aspect mining algorithms. Then, we evaluate the performance of anomaly detection techniques and choose the best anomaly detection algorithm. Later, we detect the top k anomaly as a query and detect their outlying aspect. Lastly, we evaluate their performance on 16 real-world healthcare datasets. The experimental results show that the latest isolation-based outlying aspect mining measure, SiNNE, has outstanding performance on this task and has promising results.

9.
Nanoscale ; 15(16): 7460-7465, 2023 Apr 27.
Article in English | MEDLINE | ID: mdl-37014636

ABSTRACT

We report a high performance UVB photodetector with a metal-semiconductor-metal device structure based on high crystal quality SnO2 microwires prepared by chemical vapor deposition. Under 10 V bias, a low dark current of 3.69 × 10-9 A and a high light-to-dark current ratio of 1630 were achieved. The device showed a high responsivity of about 1353.0 A·W-1 under 322 nm light illumination. The detectivity of the device is as high as 5.4 × 1014 Jones, which ensures the detection of weak signals in the UVB spectral region. Due to the small amount of deep-level defect-induced carrier recombination, the light response rise time and fall time are shorter than 0.08 s.

10.
Small Methods ; 7(7): e2300041, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37096880

ABSTRACT

This work reports a high-detectivity solar-blind deep ultraviolet photodetector with a fast response speed, based on a nitrogen-doped graphene/ßGa2 O3 /GaN p-i-n heterojunction. The i layer of ßGa2 O3 with a Fermi level lower than the central level of the forbidden band of 0.2 eV is obtained by reversed substitution growth with oxygen replacing nitrogen in the GaN matrix, indicating the majority carrier is hole. X-ray diffractometershows that the transformation of GaN into ßGa2 O3 with (-201) preferred orientation at temperature above 900 °C in an oxygen ambient. The heterojunction shows enhanced self-powered solar blind detection ability with a response time of 3.2 µs (rise)/0.02 ms (delay) and a detectivity exceeding 1012 Jones. Under a reverse bias of -5 V, the photoresponsivity is 8.3 A W-1 with a high Ilight /Idark ratio of over 106 and a detectivity of ≈9 × 1014 Jones. The excellent performance of the device is attributed to 1) the continuous conduction band without a potential energy barrier, 2) the larger built-in potential in the heterojunction because of the downward shift of Fermi energy level in ß-Ga2 O3 , and 3) an enhanced built-in electric field in the ßGa2 O3 due to introducing p-type graphene with a high hole concentration of up to ≈1020 cm-3 .

12.
Small ; 19(16): e2206664, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36683220

ABSTRACT

An excellent broad-spectrum (220-380 nm) UV photodetector, covering the UVA-UVC wavelength range, with an ultrahigh detectivity of ≈1015  cm Hz1/2 W-1 , is reported. It is based on a p-ß Ga2 O3 /n-GaN heterojunction, in which p-ß Ga2 O3 is synthesized by thermal oxidation of GaN and a heterostructure is constructed with the bottom n-GaN. XRD shows the oxide layer is (-201) preferred oriented ß-phase Ga2 O3 films. SIMS and XPS indicate that the residual N atoms as dopants remain in ß Ga2 O3 . XPS also demonstrates that the Fermi level is 0.2 eV lower than the central level of the band gap, indicating that the dominant carriers are holes and the ß Ga2 O3 is p-type conductive. Under a bias of -5 V, the photoresponsivity is 56 and 22 A W-1 for 255 and 360 nm, respectively. Correspondingly, the detectivities reach an ultrahigh value of 2.7 × 1015  cm Hz1/2 W-1 (255 nm) and 1.1 × 1015  cm Hz1/2 W-1 (360 nm). The high performance of this UV photodetector is attributed mainly to the continuous conduction band of the p-ß Ga2 O3 /n-GaN heterojunction without a potential energy barrier, which is more helpful for photogenerated electron transport from the space charge region to the n-type GaN layer.

13.
Eur Arch Otorhinolaryngol ; 280(5): 2435-2443, 2023 May.
Article in English | MEDLINE | ID: mdl-36646937

ABSTRACT

OBJECTIVE: Bariatric surgery (BS) is considered one of the most effective treatments for obese individuals with Obstructive Sleep Apnea (OSA). However, otolaryngologists have raised concerns about the structural alterations caused by BS on the upper respiratory tract, especially, on the pharyngeal cavity. METHODS: In this study, we recruited 42 individuals who underwent BS at our hospital. They were divided into two groups based on apnea-hypopnea index (AHI): mild group (5 ≤ AHI < 15) and moderate-severe group (AHI ≥ 15). The participants were followed up for 12 months and several indicators, including body mass index (BMI), polysomnography (PSG), and acoustic pharyngometry (APh), were assessed repeatedly before surgery and at 3, 6, and 12 months (m) after surgery. RESULTS: Participants exhibited significant decreases in BMI (F = 128.1, P = 0.001) and total weight loss (F = 176.7, P < 0.001) after BS. The AHI value among obese patients with mild OSA decreased significantly within three months after surgery (0 day vs. 3 months, P < 0.01), and decreased significantly more than 12 months with moderate-to-severe patients (0 day vs. 3 months, 3 months vs. 6 months, 6 months vs. 12 months, P < 0.01). The therapeutic effect of OSA of the mild group was significantly better compared with that of the moderate-severe group at 6 months (mean rank = 28.13 vs. 14.21, P < 0.001) and 12 m (mean rank = 26.75 vs. 15.52, P = 0.001). The APh results revealed that the pharyngeal volume of the two groups increased significantly between 0 day and 6 months after surgery (P < 0.01). The oropharyngeal junction (OPJ) area and the glottal area were increased significantly between 0 day and 6 m after surgery (P < 0.01). CONCLUSION: BS can relieve apnea and OSA symptoms among obese patients with OSA, especially in the early postoperative period. Moreover, OSA severity was closely associated with OPJ and glottal areas, rather than pharyngeal cavity volume.


Subject(s)
Bariatric Surgery , Sleep Apnea, Obstructive , Humans , Obesity/complications , Obesity/surgery , Sleep Apnea, Obstructive/complications , Sleep Apnea, Obstructive/surgery , Sleep Apnea, Obstructive/diagnosis , Bariatric Surgery/adverse effects , Pharynx/surgery , Postoperative Period
14.
Front Microbiol ; 13: 1018682, 2022.
Article in English | MEDLINE | ID: mdl-36353453

ABSTRACT

Escherichia coli is considered an opportunistic pathogen and an indicator for antimicrobial resistance (AMR) monitoring. Despite many reports on its AMR monitoring, studies based on genome-based analysis of AMR genes are still insufficient. Here, 181 E. coli strains were isolated from anal swab samples collected from pigs and chickens of animal farms located in Eastern China and sequenced through the Illumina platform. The results showed that 87.85% (159/181) of the E. coli isolates were multidrug-resistant (MDR). Ampicillin (AMP)- spectinomycin (SPT)- tetracycline (TET)- florfenicol (FFC)- sulfisoxazole (SF)- trimethoprim/sulfamethoxazole (SXT) was the predominant AMR pattern. By whole-genome sequencing, we found that ST10 (10.49%, 19/181) and ST48 (7.18%, 13/181) were major sequence types. IncFIB and IncX1 were the most prevalent plasmid replicons. The AMR genes bla NDM-5 (1.10%, 2/181), mcr-1 (1.10%, 2/181), tet(X4) (1.10%, 2/181), and cfr (6.08%, 2/181) were also found in these isolates. In addition, among the 169 virulence genes detected, we identified astA (37.02%, 67/181), hlyA (1.66%, 3/181), hlyB (1.66%, 3/181) and hlyD (1.66%, 3/181), which were closely related to heat-stable enterotoxin 1 and α-hemolysin. In addition, there were 33 virulence genes associated with the iron uptake system, and 46 were adhesion-related genes. Our study highlighted the need for routine surveillance of AMR with advanced genomic approaches, providing up-to-date data on the prevalence of AMR for the development and execution of antimicrobial stewardship policy.

15.
Cells ; 11(21)2022 11 03.
Article in English | MEDLINE | ID: mdl-36359876

ABSTRACT

Antimicrobial-resistant (AMR) pathogens are a significant threat to public health worldwide. However, the primary carrier of AMR genes, particularly against last-resort antibiotics, is still only partially studied in Chinese hospitals. In a sentinel hospital in China, we collected 157 E. coli strains from patients between January and July 2021. One blaNDM-1-, nine blaNDM-5-, and one mcr-1-positive E. coli recovered from inpatients were identified as resistant to meropenem and colistin. There are 37 virulence genes discovered in the 11 strains, including astA in strain EC21Z-147 (O128: H4), which belongs to the enteroaggregative E. coli (EAEC). The blaNDM gene is distributed into distinct ST types, including ST48, ST616, ST410, ST711, and ST2003, while the mcr-1 gene was identified in ST117. The conjugative plasmids IncX3, IncI1-I, and IncI2 mediated the blaNDM-5 and mcr-1 genes detected among inpatients. Notably, the youngest age at which mcr-1-positive E. coli has been reported was at one day old, in a child in which the strain is closely related to strains with animal origins. Hospitals are major environments for the spread and dissemination of critical virulence and AMR genes, which requires active monitoring systems at the genome level to surveil the spread of virulence and AMR.


Subject(s)
Escherichia coli Infections , Escherichia coli Proteins , Animals , Colistin/pharmacology , Escherichia coli/genetics , Carbapenems/pharmacology , Escherichia coli Proteins/genetics , beta-Lactamases/genetics , Plasmids , Microbial Sensitivity Tests , Escherichia coli Infections/drug therapy , Hospitals
16.
Microbiol Spectr ; 10(6): e0210222, 2022 12 21.
Article in English | MEDLINE | ID: mdl-36301090

ABSTRACT

New Delhi metallo-ß-lactamase (NDM)-producing clinical strains in Acinetobacter spp. have been recently reported in many countries and have received considerable attention. The vast majority of blaNDM cases occur on conjugative plasmids, which play a vital role in disseminating blaNDM. To characterize the conjugative plasmids bearing blaNDM genes in Acinetobacter spp., we analyzed the variants of blaNDM, conjugative transfer regions, genetic contexts of blaNDM, and the phylogenetic pattern of the 62 predicted blaNDM-positive plasmids, which were selected from 1,191 plasmids of Acinetobacter species from GenBank. We identified 30 conjugative plasmids from the 62 blaNDM-harboring plasmids in Acinetobacter species, with the oriT sites similar to plasmid pNDM-YR7 in our study, genes coding for relaxases of the MOBQ family, genes encoding type IV coupling proteins (T4CPs) of the TrwB/TraD subfamily, and VirB-like type IV secretion system (T4SS) gene clusters. The genome sizes of all 30 pNDM-YR7-like plasmids ranged from 39.36 kb to 49.65 kb, with a median size of 44.56 kb. The most common species of Acinetobacter containing the blaNDM-positive conjugative plasmids was A. baumannii, followed by Acinetobacter lwoffii and Acinetobacter indicus. Notably, pNDM-YR7 is the first report on a blaNDM-positive conjugative plasmid in Acinetobacter junii. Moreover, all 30 blaNDM-positive conjugative plasmids in Acinetobacter species were found to contain genetic contexts with the structure ISAba14-aph(3')-VI-ISAba125-blaNDM-ble. Our findings provide important insights into the phylogeny and evolution of blaNDM-positive plasmids of Acinetobacter species and further address their role in acquiring and spreading blaNDM genes in Acinetobacter species. IMPORTANCE Conjugative plasmids harboring the blaNDM gene play a vital role in disseminating carbapenem resistance. In this study, we first report a conjugative plasmid, pNDM-YR7, in Acinetobacter junii. Based on the genomic characteristics of the blaNDM-positive pNDM-YR7, we performed in silico typing and comparative analysis of blaNDM-positive plasmids using the 1,191 plasmids of Acinetobacter species available in the NCBI RefSeq database. We analyzed the characteristics of blaNDM-positive plasmids, including the variants of blaNDM, genetic features associated with blaNDM, conjugative transfer regions, and the phylogenetic pattern of the blaNDM-positive plasmids. All 30 blaNDM-positive conjugative plasmids were found to contain an ISAba14-aph(3')-VI-ISAba125-blaNDM-ble region. This study provides novel insights into the phylogeny and evolution of blaNDM-harboring conjugative plasmids and contributes to the repertoire of knowledge surrounding blaNDM-positive plasmids in the genus Acinetobacter.


Subject(s)
Acinetobacter , Phylogeny , Acinetobacter/genetics , Plasmids/genetics , beta-Lactamases/genetics , Anti-Bacterial Agents/pharmacology , Microbial Sensitivity Tests
17.
Front Microbiol ; 13: 885132, 2022.
Article in English | MEDLINE | ID: mdl-35935206

ABSTRACT

Antimicrobial resistance (AMR) may lead to worldwide epidemics through human activities and natural transmission, posing a global public safety threat. Colistin resistance mediated by the mcr-1 gene is the most prevalent among animal-derived Escherichia coli, and mcr-1-carrying E. coli have been frequently detected in central-eastern China. However, animal-derived E. coli with AMR and the prevalence of mcr-1 in the Qinghai Plateau have been rarely investigated. Herein, 375 stool samples were collected from 13 poultry farms in Qinghai Province and 346 E. coli strains were isolated, of which eight carried mcr-1. The AMR rates of the E. coli strains to ampicillin, amoxicillin/clavulanic acid, and tetracycline were all above 90%, and the resistance rates to ciprofloxacin, cefotaxime, ceftiofur, and florfenicol were above 70%. Multidrug-resistant strains accounted for 95.66% of the total isolates. Twelve E. coli strains showed colistin resistance, from which a total of 46 AMR genes and 36 virulence factors were identified through whole-genome sequencing. The mcr-1 gene resided on the IncHI2, IncI2-type and IncY-type plasmids, and mcr-1 was located in the nikA-nikB-mcr-1-pap2 gene cassette (three strains) or the pap2-mcr-1-ISApl1 structure (one strain). Completed IncI2-type plasmid pMCR4D31-3 sequence (62,259 bp) revealed that it may cause the horizontal transmission of mcr-1 and may increase the risk of its spread through the food chain. Taken together, the AMR of chicken-derived E. coli in the plateau is of concern, suggesting that it is very necessary for us to strengthen the surveillance in various regions under the background of one health.

18.
Microbiol Spectr ; 10(4): e0201522, 2022 08 31.
Article in English | MEDLINE | ID: mdl-35950758

ABSTRACT

Widely distributed multidrug-resistant (MDR) bacteria threaten animals and human health. Nevertheless, few antimicrobial resistance (AMR) surveys of large-scale animal-derived bacteria have been explored. Here, 1,468 (97.54%) Escherichia coli strains were isolated from 1,505 pig (1,060) and chicken (445) anal swab samples from 11 cities in Zhejiang Province, China, in 2020. These isolates had a high resistance to tetracycline (92.92%), sulfisoxazole (93.05%), florfenicol (83.11%), and ampicillin (78.27%). More than 88.68% of the strains were MDR bacteria. A low AMR ratio to the "last-resort" antimicrobials tigecycline (0.75%), colistin (1.36%), and meropenem (0.75%) were found. The AMR of E. coli from pigs was higher than that of chickens. Eighteen strains among 31 MDR strains that were resistant to "last-resort" antimicrobials could transfer the AMR genes (mcr-1, tet(X), and blaNDM) to the recipient strain J53, which confer colistin, tigecycline, and carbapenem resistance, respectively. The homology among mcr-1-carrying isolates was relatively high, and the sequence types were mainly ST5529, ST101, and ST354, while the homology of isolates harboring tet(X4) and blaNDM-5 genes were different. The mcr-1, blaNDM-5, and tet(X4) genes in strains LS45, JH51, and TZ118 were identified on the Incl2, IncHI2, and IncX1 plasmids, respectively. Moreover, tet(A), sul2, floR, and blaTEM-1B were the most common ARGs in 31 strains. Additionally, the heavy metals copper and zinc had a significant correlation with amoxicillin/clavulanate and tetracycline resistance. Controlling the movement of animals between cities and reducing the use of antimicrobials are effective methods to reduce the threat of AMR bacteria. IMPORTANCE Pigs and chickens are the most common food animals that are the important vectors for spreading antimicrobial-resistant pathogens among animals and humans. Limited systematic AMR monitoring of these food animal origin bacteria had been reported, especially in developed areas of China. Our study provides a comprehensive and systematic study of AMR in Escherichia coli from eastern China. The AMR of E. coli strains among the animals or cities has statistically significant differences. Moreover, the mcr-1, tet(X4), and blaNDM-5 genes, considered resistant to the last line of AMR, were identified in part of farms. The transferability and the prevalence of these AMR strains were intensively studied. Our monitoring is comparable to human clinical research and has an essential reference for public health safety. These findings will provide early warning for AMR strains and guide the clinical use of antibiotics to control the spread of antibiotic resistance.


Subject(s)
Escherichia coli Infections , Escherichia coli Proteins , Animals , Anti-Bacterial Agents/pharmacology , Chickens , Colistin/pharmacology , Drug Resistance, Bacterial/genetics , Escherichia coli , Escherichia coli Infections/microbiology , Escherichia coli Infections/veterinary , Escherichia coli Proteins/genetics , Humans , Microbial Sensitivity Tests , Plasmids/genetics , Swine , Tigecycline/pharmacology
19.
Article in English | MEDLINE | ID: mdl-35886248

ABSTRACT

Noise-induced annoyance is one person's individual adverse reaction to noise. Noise annoyance is an important basis for determining the acceptability of environmental noise exposure and for formulating environmental noise standards. It is influenced by both acoustic and non-acoustic factors. To identify non-acoustic factors significantly influencing noise annoyance, 40 noise samples with a loudness level of 60-90 phon from 500-1000 kV substations were selected in this study. A total of 246 subjects were recruited randomly. Using the assessment scale of noise annoyance specified by ISO 15666-2021, listening tests were conducted. Meanwhile, basic information and noise sensitivity of each subject were obtained through a questionnaire and the Weinstein's noise sensitivity scale. Based on the five non-acoustic indices which were identified in this study and had a significant influence on noise annoyance, a prediction model of annoyance from substation noise was proposed by a stepwise regression. Results showed that the influence weight of acoustic indices in the model accounted for 80% in which the equivalent continuous A-weighted sound pressure level and the sound pressure level above 1/1 octave band of 125 Hz were 65% and 15%, respectively. The influence weight of non-acoustic indices entering the model was 20% in which age, education level, noise sensitivity, income, and noisy degree in the workplace were 8%, 2%, 4%, 4%, and 2%, respectively. The result of this study can provide a basis for factors identification and prediction of noise annoyance.


Subject(s)
Loudness Perception , Noise , Acoustics , Auditory Perception , Environmental Exposure , Humans , Noise/adverse effects
20.
J Glob Antimicrob Resist ; 30: 249-251, 2022 09.
Article in English | MEDLINE | ID: mdl-35793774

ABSTRACT

OBJECTIVES: This study aimed to identify tigecycline-resistant tet(X4)-bearing Escherichia fergusonii isolated from pigs in China with a complete genome sequence. METHODS: E. fergusonii was isolated by selective medium and screened from tigecycline-supplemented agar plates. The microbroth dilution method was used for antimicrobial susceptibility testing, and the minimal inhibitory concentration (MIC) results refer to the interpretation standard in the Clinical and Laboratory Standards Institute of America (CLSI). Whole-genome sequencing was performed on the Illumina HiSeq and Nanopore GridION platforms. The antimicrobial resistance (AMR) genes virulence genes and replicon types of plasmids were predicted by the CGE server. RESULTS: E. fergusonii EF21QZZ116 was identified from 760 faecal and caecal content samples and was resistant to tigecycline, tetracycline, ampicillin, sulfisoxazole, trimethoprim-sulfamethoxazole, spectinomycin, and florfenicol. The AMR genes tet(X4), blaTEM-1B, and floR are located on the hybrid IncFIA-IncHI1A-IncHI1B plasmid pQZZ166-tetX-190K and are 190 391 bp in length. This hybrid plasmid has high homology with the plasmids of Escherichia coli, Enterobacter cloacae, Klebsiella, Citrobacter, and Salmonella based on comparison and analysis with the NCBI database. Notably, conjugative transfer and S1 nuclease pulsed-field gel electrophoresis (S1-PFGE) assays show that the plasmid can transfer horizontally. CONCLUSION: To the best of our knowledge, this is the first report of E. fergusonii carrying the tet(X4) gene isolated from a pig; this report provides insight into the AMR characteristics of E. fergusonii and offers insight into public health.


Subject(s)
Escherichia coli Infections , Animals , Anti-Bacterial Agents/pharmacology , Escherichia , Escherichia coli , Plasmids/genetics , Swine , Tigecycline/pharmacology
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