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1.
J Environ Manage ; 285: 112101, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33609977

RESUMO

The bioavailability of heavy metals in compost is critical for their agronomic value. The effect of inorganic additives (rock phosphate, PR and boron waste, BW) on Copper (Cu) and Zinc (Zn) bioavailability during co-compost of swine manure and rice straw was assessed using sequential extraction procedure (European Community Bureau of Reference). The result showed that both additives, applied at rates of 2.5%-7.5% (w/w) could promote the change of exchangeable Cu and reducible Cu into oxidizable Cu, thereby reducing their bioavailability factor (BF) by 15.5%-47.2%. While additives provided no significant reduction in BF of Zn, the shift from exchangeable Zn into reducible Zn can still reduce the mobility of Zn. Based on redundancy analysis (RDA), organic matter (OM) and electrical conductivity (EC) were identified as the most important controlling factors for redistribution of Cu and Zn fractions during composting. The inorganic additives strengthened the passivation of Cu and Zn bioavailability by stimulating OM degradation. The 7.5% (w/w) rock phosphate showed best passivating effect on the bioavailability of Cu.

2.
J Chem Phys ; 154(7): 074303, 2021 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-33607888

RESUMO

Gold fluoride is a very unique species. In this work, we reported the resonant photodetachment spectra of cryogenically cooled AuF- via the slow-electron velocity-map imaging method. We determined the electron affinity of AuF to be 17 976(8) cm-1 or 2.2287(10) eV. We observed a dipole-bound state with a binding energy of 24(8) cm-1, a valence excited state with a binding energy of 1222(11) cm-1, and a resonant state with an energy of 814(12) cm-1 above the photodetachment threshold. An unusual vibrational transition with Δn = -3 was observed in the autodetachment from the dipole-bound state. Moreover, two excited states of neutral AuF were recognized for the first time, located at 13 720(78) cm-1 and 16 188(44) cm-1 above the AuF ground state.

3.
Vet Res ; 52(1): 30, 2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33618766

RESUMO

Host proteins interacting with pathogens are receiving more attention as potential therapeutic targets in molecular medicine. Streptococcus suis serotype 2 (SS2) is an important cause of meningitis in both humans and pigs worldwide. SS2 Enolase (Eno) has previously been identified as a virulence factor with a role in altering blood brain barrier (BBB) integrity, but the host cell membrane receptor of Eno and The mechanism(s) involved are unclear. This study identified that SS2 Eno binds to 40S ribosomal protein SA (RPSA) on the surface of porcine brain microvascular endothelial cells leading to activation of intracellular p38/ERK-eIF4E signalling, which promotes intracellular expression of HSPD1 (heat-shock protein family D member 1), and initiation of host-cell apoptosis, and increased BBB permeability facilitating bacterial invasion. This study reveals novel functions for the host-interactional molecules RPSA and HSPD1 in BBB integrity, and provides insight for new therapeutic strategies in meningitis.

5.
Vet Microbiol ; 254: 108981, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33445055

RESUMO

Streptococcus suis serotype 2 (SS2) is an important zoonotic pathogen that causes meningitis. The ubiquitously expressed 40S ribosome protein SA (RPSA) is a multifunctional protein involved in the pathogenesis of multiple pathogens, especially those causing meningitis. However, the role of RPSA in SS2-induced meningitis is not clear. In this study, immunofluorescence staining revealed that SS2 infection promoted the intracellular transfer of RPSA to the surface of human cerebral microvascular endothelial cells (HCMECs). Moreover, SS2 infection promoted the accumulation of caveolin 1 (CAV1) and the formation of membrane bulges where RPSA enveloped CAV1 on the cell surface. SS2 infection also caused dynamic changes in the localization of RPSA and CAV1 on the cell surface which could be eliminated by disruption of caveolae/rafts by addition of methyl-ß-cyclodextrin (MßCD). Co-immunoprecipitation analysis demonstrated that α-enolase (ENO), a key virulence factor of SS2, interacted with RPSA, and promoted the interaction between RPSA and CAV1. Immunofluorescence staining, western blotting and flow cytometry analyses showed that damaged caveolae/rafts significantly enhanced ENO adhesion to HCMECs, promoted the "destruction" of RPSA by ENO, and enhanced the toxic effect of ENO on HCMECs. Importantly, these effects could be relieved upon the addition of cholesterol. We conclude that caveolae/rafts weaken the toxic effect of SS2 ENO on RPSA-mediated events in HCMECs. Our study has led to better understanding of the roles of RPSA and caveolae/rafts upon SS2 infection, and a new pathological role for RPSA in infection.

6.
Oncol Rep ; 45(3): 1118-1132, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33432363

RESUMO

An increasing number of studies have demonstrated that long non­coding (lnc)RNAs are associated with tumor invasion, metastasis and the prognosis of patients with a variety of different tumors. However, the roles of lncRNA prostate androgen regulated transcript 1 (PART1) in esophageal squamous cell carcinoma (ESCC) remain unknown. In the present study, reverse transcription­quantitative PCR was performed to investigate the levels of PART1, SRY­box transcription factor 6 (SOX6) and miR­18a­5p in ESCC tissues and cells. The functions of PART1 in ESCC were demonstrated using Cell Counting Kit­8 and Matrigel assays. Promoter activity and dual­luciferase reporter assays, RNA immunoprecipitation and western blot analyses were also used to determine the potential mechanisms of PART1 in ESCC cell lines. It was found that PART1 and SOX6 were both downregulated in ESCC tissues and cells, and their low expression levels were associated with TNM stage, lymph node metastasis and poor prognosis in patients with ESCC. Forkhead box protein P2 (FOXP2) exhibited low expression level in ESCC tissues, and its expression was positively correlated with PART1 expression level in ESCC tissues. FOXP2 was found to bind to the promoter region of PART1 to regulate its expression in ESCC cells. Functionally, PART1 overexpression suppressed cell proliferation and invasion, whereas PART1 downregulation promoted cell proliferation and invasion in the ESCC cell lines. Mechanistically, PART1 functions as a competing endogenous (ce)RNA by sponging miR­18a­5p, resulting in the upregulation of the downstream target gene, SOX6, coupled with the inactivation of the ß­catenin/c­myc signaling axis, to suppress ESCC cell proliferation and invasion. In conclusion, data from the present study unveil a potential ceRNA regulatory pathway, in which PART1 affects SOX6 expression level by sponging miR­18a­5p, to ultimately suppress ESCC development and progression.

7.
EMBO Rep ; : e51163, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33492731

RESUMO

The phagosome harboring the bacterial pathogen Legionella pneumophila is known to be enriched with phosphatidylinositol 4-phosphate (PtdIns4P), which is important for anchoring a subset of its virulence factors and potentially for signaling events implicated in the biogenesis of the Legionella-containing vacuole (LCV) that supports intracellular bacterial growth. Here we demonstrate that the effector MavQ is a phosphoinositide 3-kinase that specifically catalyzes the conversion of phosphatidylinositol (PtdIns) into PtdIns3P. The product of MavQ is subsequently phosphorylated by the effector LepB to yield PtdIns(3,4)P2, whose 3-phosphate is then removed by another effector SidF to generate PtdIns4P. We also show that MavQ is associated with the LCV and the ∆mavQ mutant displays phenotypes in the anchoring of a PtdIns4P-binding effector similar to those of ∆lepB or ∆sidF mutants. Our results establish a mechanism of de novo PtdIns4P biosynthesis by L. pneumophila via a catalysis axis comprised of MavQ, LepB, and SidF on the surface of its phagosome.

8.
J Ethnopharmacol ; 268: 113695, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33316365

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: In Chinese folk medicine, Ligustrum robustum (Roxb.) Blume has been widely used as a healthy tea beverage for improvement in obesity and lipidemic metabolic disorders. AIM OF THE STUDY: We aimed to investigate the effect of L. robustum extract (LRE) on metabolic syndrome in high-fat diet (HFD)-fed mice and to explore the underlying role of gut microbiota during the treatment. MATERIALS AND METHODS: The ground dried leaves of L. robustum (Roxb.) Blume were extracted with ethanol and then purified by a resin column. The composition of L. robustum extract (LRE) was analyzed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). C57BL/6 J mice fed with HFD were treated with LRE for 16 weeks. RT-qPCR and morphological staining were utilized to reveal the impact of LRE on hepatic glucolipid metabolism and gut integrity. The next-generation sequencing of 16 S rDNA was applied for analyzing the gut microbial community of fecal samples. RESULTS: LRE, mainly composed of ligupurpuroside A and aceteoside, alleviated insulin resistance, improved hepatic metabolism, enhanced intestinal integrity, and suppressed inflammatory responses in HFD-fed mice. Moreover, LRE treatment reshaped the gut microbiota structure by increasing the levels of genera Streptococcus, Lactobacillus, and Mucispirillum and decreasing the populations of Alistipes and Lachnospiraceae NK4A136 group in HFD-fed mice. The alteration of gut microbiota was associated with several metabolic pathways of gut bacteria. Spearman's correlation analysis further confirmed the links between the changed intestinal bacteria and multiple disease indices. CONCLUSIONS: LRE prevented gut microbiota dysbiosis and metabolic disorder in HFD-fed mice, which helps to promote the application in LRE-mediated prevention from metabolic syndrome as a gut microbial regulator.

9.
Eur J Pharm Sci ; 158: 105676, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33310029

RESUMO

Lactulose is a common laxative and has been widely applied to clinical treatment for constipation. This study aimed to explore the improving effect of lactulose on constipation through the mediation of gut microbiota and intestinal metabolites. BALB/c mice with constipation induced by loperamide were orally treated with lactulose for four weeks. After the treatment, the constipation-related factors were determined. The effect of lactulose on the composition of gut microbiota was assessed by 16S rDNA gene sequencing. Gas chromatography or liquid chromatography-mass spectrometer (GC/LC-MS) analysis was used for the quantification of intestinal metabolites. The treatment of constipated mice with lactulose accelerated intestinal motility, suppressed inflammatory responses, protected gut barrier, and improved metabolisms of water and salt in the intestinal tract. These therapeutic effects were attributed to the reversed gut microbiota dysfunction, which conferred the benefit to the production of intestinal metabolites including bile acids, short-chain fatty acids, and tryptophan catabolites. Further, the depletion of intestinal flora from loperamide- or (loperamide + lactulose)-treated mice confirmed the significance of gut microbiota in the mediation of constipation. In summary, this study leads us to propose that lactulose may improve constipation through a prebiotic effect on gut microbiota and intestinal metabolites.

10.
Bioresour Technol ; 319: 124114, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32942236

RESUMO

Conventional treatment and recycling methods of organic solid waste contain inherent flaws, such as low efficiency, low accuracy, high cost, and potential environmental risks. In the past decade, machine learning has gradually attracted increasing attention in solving the complex problems of organic solid waste treatment. Although significant research has been carried out, there is a lack of a systematic review of the research findings in this field. This study sorts the research studies published between 2003 and 2020, summarizes the specific application fields, characteristics, and suitability of different machine learning models, and discusses the relevant application limitations and future prospects. It can be concluded that studies mostly focused on municipal solid waste management, followed by anaerobic digestion, thermal treatment, composting, and landfill. The most widely used model is the artificial neural network, which has been successfully applied to various complicated non-linear organic solid waste related problems.


Assuntos
Eliminação de Resíduos , Gerenciamento de Resíduos , Aprendizado de Máquina , Reciclagem , Resíduos Sólidos/análise , Instalações de Eliminação de Resíduos
11.
Carbohydr Polym ; 253: 117218, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33278982

RESUMO

This study was designed to explore the improvement of chitosan oligosaccharides (COS) on constipation through regulation of gut microbiota. Here, we proved that COS treatment profoundly boosted intestinal motility, restrained inflammatory responses, improved water-electrolyte metabolism and prevented gut barrier damage in constipated mice induced by loperamide. By 16S rDNA gene sequencing, the disbalanced gut microbiota was observed in constipated mice, while COS treatment statistically reversed the abundance changes of several intestinal bacteria at either phylum, family and genus levels, which partly led to the balance in production of intestinal metabolites including bile acids, short-chain fatty acids and tryptophan catabolites. In addition, COS failed to relieve the constipation in mice with intestinal flora depletion, confirming the essentiality of gut microbiota in COS-initiated prevention against constipation. In summary, COS can ameliorate the development of loperamide-induced constipation in mice by remodeling the structure of gut microbial community.

12.
Artigo em Inglês | MEDLINE | ID: mdl-33347766

RESUMO

Continuous-flow left ventricular assist devices (CFLVADs) routinely operate at a constant speed for the support of a failing heart, which decreases the pulsatility in the arteries. Some late complications could be related to a long-term lack of pulsatility. Modulating the CFLVAD speed is a solution to enhance the pulsatility. The purpose of this study is to modulate multiple varying speed patterns and investigate their effects on the ventricle and vascular system. A cardiovascular coupling numerical model is developed to provide a simulation platform for testing the varying speed patterns. The varying speed patterns are modulated by combining the shape, amplitude, frequency, phase shift, and pulsatile duty cycle of the speed profile. The influence of varying speed support is examined by analyzing the indexes of pulsatility, indexes of ventricular unloading, and hemodynamic variables. The results show that the synchronous counterpulsation pattern can effectively reduce the ventricular unloading indexes, whereas the low-frequency asynchronous pattern can effectively increase the vascular pulsatility indexes. Also, the hemodynamics with synchronous varying speed support is more physiological than that with asynchronous varying speed support. This study provides valuable insight for further optimization of varying speed modulation by weighing vascular pulsatility, ventricular unloading, and hemodynamics.

13.
Math Biosci Eng ; 17(6): 7519-7543, 2020 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-33378908

RESUMO

The mathematical modeling of the cardiovascular system is a simple and noninvasive method to comprehend hemodynamics and the operating mechanism of the mechanical circulatory assist device. In this study, a numerical model was developed to simulate hemodynamics under different conditions and to evaluate the operating condition of continuous-flow left ventricular assist device (LVAD). The numerical model consisted of a cardiovascular lumped parameter (CLP) model, a baroreflex model, and an LVAD model. The CLP model was established to simulate the human cardiovascular system including the left heart, right heart, systemic circulation, and pulmonary circulation. The baroreflex model was used to regulate left and right ventricular end-systolic elastances, systemic vascular resistance, and heart rate. The centrifugal pump HeartMate III used as an example to simulate the rotary pump dynamics at different operating speeds. Simulation results show that hemodynamics under normal, left ventricular failure and different levels of pump support conditions can be reproduced by the numerical model. Based on simulation results, HeartMate III operating speed can be maintained between 3600 rpm and 4400 rpm to avoid pump regurgitation and ventricular suction. Additionally, in the simulation system, the HeartMate III operating speed should be between 3600 rpm and 3800 rpm to provide optimal physiological perfusion. Thus, the developed numerical model is a feasible solution to simulate hemodynamics and evaluate the operating condition of continuous-flow LVAD.

14.
Chemosphere ; : 128799, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33187658

RESUMO

In this work, Ti/PbO2-Co-Sm electrode has been successfully prepared using electrodeposition and further applied for the electrocatalysis of atrazine (ATZ) herbicide wastewater. As expected, Ti/PbO2-Co-Sm electrode displays highest oxygen evolution potential, lowest charge transfer resistance, longest service lifetime and most effective electrocatalytic activity compared with Ti/PbO2, Ti/PbO2-Sm and Ti/PbO2-Co electrodes. Orthogonal and single factor experiments are designed to optimize the condition of ATZ degradation. The maximum degradation efficiency of 92.6% and COD removal efficiency of 84.5% are achieved in electrolysis time 3 h under the optimum condition (current density 20 mA cm-2, Na2SO4 concentration 8.0 g L-1, pH 5 and temperature 35 °C). In addition, Ti/PbO2-Co-Sm electrode exhibits admirable recyclability in degradation progress. The degradation of ATZ is accomplished by indirect electrochemical oxidation and ∙OH is tested as the main active substance in ATZ oxidation. The possible degradation mechanism of ATZ has been proposed according to the degradation intermediates detected by LC-MS. This research suggests that Ti/PbO2-Co-Sm is a promising electrode for ATZ degradation.

15.
Artigo em Inglês | MEDLINE | ID: mdl-33191469

RESUMO

In order to explore the comprehensive utilisation and recycling technology of Caragana korshinskii resources, a new agricultural biomass waste, 15 kinds of Caragana korshinskii biochar (CB) were prepared by controlling the pyrolysis temperature and time at the anaerobic environment. Moreover, we pay more attention to deriving the adsorption mechanisms and exploring the difference in adsorption characteristics of Pb2+ and Cd2+. The optimal preparation conditions and the batch adsorption experiments were evaluated, and the adsorption characteristics and mechanisms were discussed using 8 theoretical adsorption models and multiple characterisation methods. The results showed that the CB prepared at 650 °C for 3 h presented the best performance. The Langmuir and Freundlich models can well simulate the isotherm adsorption process of CB for Pb2+ and Cd2+, respectively. The adsorption kinetics of CB for Pb2+ and Cd2+ were best fitted by the pseudo-second-order model. The adsorption equilibrium for Pb2+ and Cd2+ was reached within 3 h, and their maximum adsorption capacity reached 220.94 mg g-1 and 42.43 mg g-1, respectively. In addition, the best addition amount was 3 g L-1 and 2.2 g L-1 for Pb2+ and Cd2+, respectively. The optimum pH range was 3-6 for Pb2+ and 6-7.5 for Cd2+. The adsorption mechanisms of CB for Pb2+ and Cd2+ were physicochemical composite adsorption processes, mainly including physical sorption on surface sites, intraparticle diffusion, electrostatic adsorption, ion/ligand exchange, cationic-π interactions, surface complexation and precipitation. Furthermore, the ash of CB also presented a positive effect on the adsorption of Pb2+. Compared with other cellulose- and lignin-based biomass materials, CB showed low cost and efficient performance without complicated modification conditions. Therefore, this study demonstrates that CB is a promising raw material in water pollution control to immobilise heavy metals.

16.
Bioresour Technol ; 320(Pt A): 124331, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33157443

RESUMO

Information on the dynamic evolution of humic acid (HA) from anaerobic digestate and the potential of HA serving as an effective agent for remedying heavy metals is rather scarce. This study monitored the evolution of the structure and functional groups and metal-binding abilities of HA during chicken manure and corn stover anaerobic digestion (AD) processes. Higher increases in aromatic (41-66%) and oxygen-containing functional groups (37-45%) were observed in HA from the AD of corn stover, resulting in higher metal-binding abilities for Cu(II), Co(II), and Ni(II) than those of chicken manure AD. Moreover, HA extracted from fast (before day 12 for chicken manure and day 16 for corn stover), and slow (day 40) methane production stages performed different complexation capacities for the heavy metals. These results reveal the mechanisms of HA and heavy metal interactions, and confirm the potential of HA extracted from AD process for the remediation of heavy metals.

17.
J Geriatr Oncol ; 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33162369

RESUMO

BACKGROUND: Autologous hematopoietic stem cell transplant (autoHCT) is a mainstay of treatment for multiple myeloma and non-Hodgkin lymphoma but is underutilized in older adults. We investigated the association of vulnerabilities identified by a geriatric assessment (GA)-guided multidisciplinary clinic (MDC) on the receipt of autoHCT and evaluated its ability to predict outcomes in older autoHCT candidates. METHODS: Patients 50+ years received GA-informed optimization recommendations: 'decline' if unlikely to realize benefits of autoHCT, 'defer' if optimization necessary before autoHCT, and 'proceed' if autoHCT could proceed without delay. We compared characteristics and outcomes of autoHCT recipients (n = 62) to non-autoHCT patients (n = 29) and evaluated GA deficits on outcomes. RESULTS: 91 patients were evaluated; the MDC recommendation was 'decline' for 5 (6%), 'defer' for 25 (27%), and 'proceed' for 61 (67%). AutoHCT recipients had fewer GA-rated impairments relative to non-autoHCT patients, as did patients with a 'proceed' recommendation relative to 'defer'. Among autoHCT recipients, 1-year and 3-year non-relapse morality (NRM) was 0% and 5%, and there was no difference in length of hospitalization, readmission rate, or mortality after transplant by MDC recommendation. Frail grip strength and poor performance status were associated with inferior post-autoHCT progression-free survival and overall survival. CONCLUSIONS: Patients pursuing autoHCT after MDC-directed optimization achieved excellent outcomes, including patients deferred but ultimately receiving autoHCT. GA-identified functional deficits, especially frail grip strength, may improve risk stratification in older autoHCT candidates. Employing a GA earlier in the disease trajectory to inform early referral to an MDC may increase autoHCT safety and utilization in older patients.

18.
Artigo em Inglês | MEDLINE | ID: mdl-33140486

RESUMO

Bile acids (BAs) play a pivotal role in manipulating the development of metabolic diseases. However, due to the compositional complexity and functional variation of BAs, it remains unclear about the changes in BA pool for individuals with obesity or metabolic syndrome. We established a high-performance liquid chromatography-mass spectrometer detection system for the simultaneous analysis of both unconjugated and conjugated BAs in the bile and feces of mice. Ten BAs were completely separated, identified, and quantified with low limit of detection (0.5 ng/mL) and inter/intraday precision (relative standard deviation < 12%). By using this method, these BAs in bile and feces of mice were quantified. The result showed that taurochenodeoxycholic acid, taurine-conjugated α-muricholic acids, and taurine-conjugated ß-muricholic acids were the dominated BAs in bile, whereas deoxycholic acid and chenodeoxycholic acid predominated in feces. Further, most of the BA levels were significantly elevated in either bile or fecal samples of high-fat diet-fed mice as compared with those in normal chow diet-fed mice, indicating that excessive production of BAs was closely associated with the occurrence of lipid metabolism disorders. In summary, the present method is practicable for analysis of BAs in bile and fecal samples of patients with obesity.

19.
J Bone Oncol ; 25: 100324, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33088701

RESUMO

Objectives: Giant cell tumors of bone (GCT) are benign with a local recurrence rate of approximately 20-50%. Growing evidence suggests that inflammation plays an important role in tumor formation and progression. Inflammatory biomarkers, including prognostic nutritional index (PNI), neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR), have little data in predicting postoperative recurrence of GCT. Methods: We retrospectively investigated 105 patients with surgery for GCT between March 2010 and June 2019 at our hospital. Through the analysis of receiver operating characteristics (ROC), the optimal cutoff values of PNI, NLR and PLR were determined. Clinical features between PNI, NLR and PLR were tested with the χ2 test. Univariate and multivariate analyses were applied to identify the prognostic factors. Results: The optimal cut-off points of PNI, NLR and PLR were 48.6, 2.4 and 136.9, respectively. In univariate analysis, PNI, NLR, PLR, tumor size, Campanacci stage were significantly associated with recurrence-free survival (RFS). Cox multivariate regression analysis revealed that the PNI (p = 0.003) and Campanacci stage (p = 0.001) were independent prognostic factors for GCT. Conclusions: PNI can be regarded as a novel independent prognostic factor for predicting postoperative recurrence in GCT.

20.
Infect Drug Resist ; 13: 3649-3655, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116684

RESUMO

Objective: A colistin-resistant Escherichia coli strain isolated from dog feces was characterized in this study. Methods and Results: A multiplex PCR assay was used to detect the presence of colistin-resistant mcr genes; it was found that E. coli QDFD216 co-harbored the mcr-1 and mcr-3 genes. Whole-genome sequencing and further bioinformatics analysis revealed that E. coli QDFD216 belonged to serotype O176:H11, fimH1311 type and ST132. The resistance genes bla CTX-M-14, mdfA, dfrA3, acrA, acrB, tolc, and sul3 were present in the chromosome. The mcr-1.1 and mcr-3.7 genes were located in two plasmids of different incompatibility groups. mcr-1.1 was carried by a IncX4-type plasmid within an typical IS26-parA-mcr-1.1-pap2 cassette, while mcr-3.7 was encoded by an IncP1-type plasmid with a genetic structure of TnAs2-mcr-3.7-dgkA-IS26. No additional antibiotic resistance genes were carried by either plasmid. Conclusion: This is the first report of an E. coli isolate co-harboring a mcr-1.1-carrying IncX4 plasmid and a mcr-3.7-carrying IncP1 plasmid. The evolution and mechanism of mcr gene co-existence need further study to assess its impact on public health.

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